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1// SPDX-License-Identifier: GPL-2.02/*3 * Driver core for Samsung SoC onboard UARTs.4 *5 * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics6 *	http://armlinux.simtec.co.uk/7 */8 9/* Note on 2410 error handling10 *11 * The s3c2410 manual has a love/hate affair with the contents of the12 * UERSTAT register in the UART blocks, and keeps marking some of the13 * error bits as reserved. Having checked with the s3c2410x01,14 * it copes with BREAKs properly, so I am happy to ignore the RESERVED15 * feature from the latter versions of the manual.16 *17 * If it becomes aparrent that latter versions of the 2410 remove these18 * bits, then action will have to be taken to differentiate the versions19 * and change the policy on BREAK20 *21 * BJD, 04-Nov-200422 */23 24#include <linux/console.h>25#include <linux/clk.h>26#include <linux/cpufreq.h>27#include <linux/delay.h>28#include <linux/dma-mapping.h>29#include <linux/dmaengine.h>30#include <linux/init.h>31#include <linux/io.h>32#include <linux/ioport.h>33#include <linux/math.h>34#include <linux/module.h>35#include <linux/of.h>36#include <linux/platform_device.h>37#include <linux/serial.h>38#include <linux/serial_core.h>39#include <linux/serial_s3c.h>40#include <linux/slab.h>41#include <linux/sysrq.h>42#include <linux/tty.h>43#include <linux/tty_flip.h>44#include <linux/types.h>45 46#include <asm/irq.h>47 48/* UART name and device definitions */49 50#define S3C24XX_SERIAL_NAME	"ttySAC"51#define S3C24XX_SERIAL_MAJOR	20452#define S3C24XX_SERIAL_MINOR	6453 54#ifdef CONFIG_ARM6455#define UART_NR			1256#else57#define UART_NR			CONFIG_SERIAL_SAMSUNG_UARTS58#endif59 60#define S3C24XX_TX_PIO			161#define S3C24XX_TX_DMA			262#define S3C24XX_RX_PIO			163#define S3C24XX_RX_DMA			264 65/* flag to ignore all characters coming in */66#define RXSTAT_DUMMY_READ (0x10000000)67 68enum s3c24xx_port_type {69	TYPE_S3C6400,70	TYPE_APPLE_S5L,71};72 73struct s3c24xx_uart_info {74	const char		*name;75	enum s3c24xx_port_type	type;76	unsigned int		port_type;77	unsigned int		fifosize;78	u32			rx_fifomask;79	u32			rx_fifoshift;80	u32			rx_fifofull;81	u32			tx_fifomask;82	u32			tx_fifoshift;83	u32			tx_fifofull;84	u32			clksel_mask;85	u32			clksel_shift;86	u32			ucon_mask;87	u8			def_clk_sel;88	u8			num_clks;89	u8			iotype;90 91	/* uart port features */92	bool			has_divslot;93};94 95struct s3c24xx_serial_drv_data {96	const struct s3c24xx_uart_info	info;97	const struct s3c2410_uartcfg	def_cfg;98	const unsigned int		fifosize[UART_NR];99};100 101struct s3c24xx_uart_dma {102	unsigned int			rx_chan_id;103	unsigned int			tx_chan_id;104 105	struct dma_slave_config		rx_conf;106	struct dma_slave_config		tx_conf;107 108	struct dma_chan			*rx_chan;109	struct dma_chan			*tx_chan;110 111	dma_addr_t			rx_addr;112	dma_addr_t			tx_addr;113 114	dma_cookie_t			rx_cookie;115	dma_cookie_t			tx_cookie;116 117	char				*rx_buf;118 119	dma_addr_t			tx_transfer_addr;120 121	size_t				rx_size;122	size_t				tx_size;123 124	struct dma_async_tx_descriptor	*tx_desc;125	struct dma_async_tx_descriptor	*rx_desc;126 127	int				tx_bytes_requested;128	int				rx_bytes_requested;129};130 131struct s3c24xx_uart_port {132	unsigned char			rx_enabled;133	unsigned char			tx_enabled;134	unsigned int			pm_level;135	unsigned long			baudclk_rate;136	unsigned int			min_dma_size;137 138	unsigned int			rx_irq;139	unsigned int			tx_irq;140 141	unsigned int			tx_in_progress;142	unsigned int			tx_mode;143	unsigned int			rx_mode;144 145	const struct s3c24xx_uart_info	*info;146	struct clk			*clk;147	struct clk			*baudclk;148	struct uart_port		port;149	const struct s3c24xx_serial_drv_data	*drv_data;150 151	/* reference to platform data */152	const struct s3c2410_uartcfg	*cfg;153 154	struct s3c24xx_uart_dma		*dma;155};156 157static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport);158 159/* conversion functions */160 161#define s3c24xx_dev_to_port(__dev) dev_get_drvdata(__dev)162 163/* register access controls */164 165#define portaddr(port, reg) ((port)->membase + (reg))166#define portaddrl(port, reg) \167	((unsigned long *)(unsigned long)((port)->membase + (reg)))168 169static u32 rd_reg(const struct uart_port *port, u32 reg)170{171	switch (port->iotype) {172	case UPIO_MEM:173		return readb_relaxed(portaddr(port, reg));174	case UPIO_MEM32:175		return readl_relaxed(portaddr(port, reg));176	default:177		return 0;178	}179	return 0;180}181 182#define rd_regl(port, reg) (readl_relaxed(portaddr(port, reg)))183 184static void wr_reg(const struct uart_port *port, u32 reg, u32 val)185{186	switch (port->iotype) {187	case UPIO_MEM:188		writeb_relaxed(val, portaddr(port, reg));189		break;190	case UPIO_MEM32:191		writel_relaxed(val, portaddr(port, reg));192		break;193	}194}195 196#define wr_regl(port, reg, val) writel_relaxed(val, portaddr(port, reg))197 198/* Byte-order aware bit setting/clearing functions. */199 200static inline void s3c24xx_set_bit(const struct uart_port *port, int idx,201				   u32 reg)202{203	unsigned long flags;204	u32 val;205 206	local_irq_save(flags);207	val = rd_regl(port, reg);208	val |= (1 << idx);209	wr_regl(port, reg, val);210	local_irq_restore(flags);211}212 213static inline void s3c24xx_clear_bit(const struct uart_port *port, int idx,214				     u32 reg)215{216	unsigned long flags;217	u32 val;218 219	local_irq_save(flags);220	val = rd_regl(port, reg);221	val &= ~(1 << idx);222	wr_regl(port, reg, val);223	local_irq_restore(flags);224}225 226static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)227{228	return container_of(port, struct s3c24xx_uart_port, port);229}230 231/* translate a port to the device name */232 233static inline const char *s3c24xx_serial_portname(const struct uart_port *port)234{235	return to_platform_device(port->dev)->name;236}237 238static bool s3c24xx_serial_txempty_nofifo(const struct uart_port *port)239{240	return rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE;241}242 243static void s3c24xx_serial_rx_enable(struct uart_port *port)244{245	struct s3c24xx_uart_port *ourport = to_ourport(port);246	unsigned long flags;247	int count = 10000;248	u32 ucon, ufcon;249 250	uart_port_lock_irqsave(port, &flags);251 252	while (--count && !s3c24xx_serial_txempty_nofifo(port))253		udelay(100);254 255	ufcon = rd_regl(port, S3C2410_UFCON);256	ufcon |= S3C2410_UFCON_RESETRX;257	wr_regl(port, S3C2410_UFCON, ufcon);258 259	ucon = rd_regl(port, S3C2410_UCON);260	ucon |= S3C2410_UCON_RXIRQMODE;261	wr_regl(port, S3C2410_UCON, ucon);262 263	ourport->rx_enabled = 1;264	uart_port_unlock_irqrestore(port, flags);265}266 267static void s3c24xx_serial_rx_disable(struct uart_port *port)268{269	struct s3c24xx_uart_port *ourport = to_ourport(port);270	unsigned long flags;271	u32 ucon;272 273	uart_port_lock_irqsave(port, &flags);274 275	ucon = rd_regl(port, S3C2410_UCON);276	ucon &= ~S3C2410_UCON_RXIRQMODE;277	wr_regl(port, S3C2410_UCON, ucon);278 279	ourport->rx_enabled = 0;280	uart_port_unlock_irqrestore(port, flags);281}282 283static void s3c24xx_serial_stop_tx(struct uart_port *port)284{285	struct s3c24xx_uart_port *ourport = to_ourport(port);286	struct s3c24xx_uart_dma *dma = ourport->dma;287	struct dma_tx_state state;288	int count;289 290	if (!ourport->tx_enabled)291		return;292 293	switch (ourport->info->type) {294	case TYPE_S3C6400:295		s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);296		break;297	case TYPE_APPLE_S5L:298		s3c24xx_clear_bit(port, APPLE_S5L_UCON_TXTHRESH_ENA, S3C2410_UCON);299		break;300	default:301		disable_irq_nosync(ourport->tx_irq);302		break;303	}304 305	if (dma && dma->tx_chan && ourport->tx_in_progress == S3C24XX_TX_DMA) {306		dmaengine_pause(dma->tx_chan);307		dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);308		dmaengine_terminate_all(dma->tx_chan);309		dma_sync_single_for_cpu(dma->tx_chan->device->dev,310					dma->tx_transfer_addr, dma->tx_size,311					DMA_TO_DEVICE);312		async_tx_ack(dma->tx_desc);313		count = dma->tx_bytes_requested - state.residue;314		uart_xmit_advance(port, count);315	}316 317	ourport->tx_enabled = 0;318	ourport->tx_in_progress = 0;319 320	if (port->flags & UPF_CONS_FLOW)321		s3c24xx_serial_rx_enable(port);322 323	ourport->tx_mode = 0;324}325 326static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport);327 328static void s3c24xx_serial_tx_dma_complete(void *args)329{330	struct s3c24xx_uart_port *ourport = args;331	struct uart_port *port = &ourport->port;332	struct tty_port *tport = &port->state->port;333	struct s3c24xx_uart_dma *dma = ourport->dma;334	struct dma_tx_state state;335	unsigned long flags;336	int count;337 338	dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);339	count = dma->tx_bytes_requested - state.residue;340	async_tx_ack(dma->tx_desc);341 342	dma_sync_single_for_cpu(dma->tx_chan->device->dev,343				dma->tx_transfer_addr, dma->tx_size,344				DMA_TO_DEVICE);345 346	uart_port_lock_irqsave(port, &flags);347 348	uart_xmit_advance(port, count);349	ourport->tx_in_progress = 0;350 351	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)352		uart_write_wakeup(port);353 354	s3c24xx_serial_start_next_tx(ourport);355	uart_port_unlock_irqrestore(port, flags);356}357 358static void enable_tx_dma(struct s3c24xx_uart_port *ourport)359{360	const struct uart_port *port = &ourport->port;361	u32 ucon;362 363	/* Mask Tx interrupt */364	switch (ourport->info->type) {365	case TYPE_S3C6400:366		s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);367		break;368	case TYPE_APPLE_S5L:369		WARN_ON(1); // No DMA370		break;371	default:372		disable_irq_nosync(ourport->tx_irq);373		break;374	}375 376	/* Enable tx dma mode */377	ucon = rd_regl(port, S3C2410_UCON);378	ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK);379	ucon |= S3C64XX_UCON_TXBURST_1;380	ucon |= S3C64XX_UCON_TXMODE_DMA;381	wr_regl(port,  S3C2410_UCON, ucon);382 383	ourport->tx_mode = S3C24XX_TX_DMA;384}385 386static void enable_tx_pio(struct s3c24xx_uart_port *ourport)387{388	const struct uart_port *port = &ourport->port;389	u32 ucon, ufcon;390 391	/* Set ufcon txtrig */392	ourport->tx_in_progress = S3C24XX_TX_PIO;393	ufcon = rd_regl(port, S3C2410_UFCON);394	wr_regl(port,  S3C2410_UFCON, ufcon);395 396	/* Enable tx pio mode */397	ucon = rd_regl(port, S3C2410_UCON);398	ucon &= ~(S3C64XX_UCON_TXMODE_MASK);399	ucon |= S3C64XX_UCON_TXMODE_CPU;400	wr_regl(port,  S3C2410_UCON, ucon);401 402	/* Unmask Tx interrupt */403	switch (ourport->info->type) {404	case TYPE_S3C6400:405		s3c24xx_clear_bit(port, S3C64XX_UINTM_TXD,406				  S3C64XX_UINTM);407		break;408	case TYPE_APPLE_S5L:409		ucon |= APPLE_S5L_UCON_TXTHRESH_ENA_MSK;410		wr_regl(port, S3C2410_UCON, ucon);411		break;412	default:413		enable_irq(ourport->tx_irq);414		break;415	}416 417	ourport->tx_mode = S3C24XX_TX_PIO;418 419	/*420	 * The Apple version only has edge triggered TX IRQs, so we need421	 * to kick off the process by sending some characters here.422	 */423	if (ourport->info->type == TYPE_APPLE_S5L)424		s3c24xx_serial_tx_chars(ourport);425}426 427static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport)428{429	if (ourport->tx_mode != S3C24XX_TX_PIO)430		enable_tx_pio(ourport);431}432 433static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,434				      unsigned int count, unsigned int tail)435{436	struct s3c24xx_uart_dma *dma = ourport->dma;437 438	if (ourport->tx_mode != S3C24XX_TX_DMA)439		enable_tx_dma(ourport);440 441	dma->tx_size = count & ~(dma_get_cache_alignment() - 1);442	dma->tx_transfer_addr = dma->tx_addr + tail;443 444	dma_sync_single_for_device(dma->tx_chan->device->dev,445				   dma->tx_transfer_addr, dma->tx_size,446				   DMA_TO_DEVICE);447 448	dma->tx_desc = dmaengine_prep_slave_single(dma->tx_chan,449				dma->tx_transfer_addr, dma->tx_size,450				DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);451	if (!dma->tx_desc) {452		dev_err(ourport->port.dev, "Unable to get desc for Tx\n");453		return -EIO;454	}455 456	dma->tx_desc->callback = s3c24xx_serial_tx_dma_complete;457	dma->tx_desc->callback_param = ourport;458	dma->tx_bytes_requested = dma->tx_size;459 460	ourport->tx_in_progress = S3C24XX_TX_DMA;461	dma->tx_cookie = dmaengine_submit(dma->tx_desc);462	dma_async_issue_pending(dma->tx_chan);463	return 0;464}465 466static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)467{468	struct uart_port *port = &ourport->port;469	struct tty_port *tport = &port->state->port;470	unsigned int count, tail;471 472	/* Get data size up to the end of buffer */473	count = kfifo_out_linear(&tport->xmit_fifo, &tail, UART_XMIT_SIZE);474 475	if (!count) {476		s3c24xx_serial_stop_tx(port);477		return;478	}479 480	if (!ourport->dma || !ourport->dma->tx_chan ||481	    count < ourport->min_dma_size ||482	    tail & (dma_get_cache_alignment() - 1))483		s3c24xx_serial_start_tx_pio(ourport);484	else485		s3c24xx_serial_start_tx_dma(ourport, count, tail);486}487 488static void s3c24xx_serial_start_tx(struct uart_port *port)489{490	struct s3c24xx_uart_port *ourport = to_ourport(port);491	struct tty_port *tport = &port->state->port;492 493	if (!ourport->tx_enabled) {494		if (port->flags & UPF_CONS_FLOW)495			s3c24xx_serial_rx_disable(port);496 497		ourport->tx_enabled = 1;498		if (!ourport->dma || !ourport->dma->tx_chan)499			s3c24xx_serial_start_tx_pio(ourport);500	}501 502	if (ourport->dma && ourport->dma->tx_chan) {503		if (!kfifo_is_empty(&tport->xmit_fifo) &&504				!ourport->tx_in_progress)505			s3c24xx_serial_start_next_tx(ourport);506	}507}508 509static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport,510		struct tty_port *tty, int count)511{512	struct s3c24xx_uart_dma *dma = ourport->dma;513	int copied;514 515	if (!count)516		return;517 518	dma_sync_single_for_cpu(dma->rx_chan->device->dev, dma->rx_addr,519				dma->rx_size, DMA_FROM_DEVICE);520 521	ourport->port.icount.rx += count;522	if (!tty) {523		dev_err(ourport->port.dev, "No tty port\n");524		return;525	}526	copied = tty_insert_flip_string(tty,527			((unsigned char *)(ourport->dma->rx_buf)), count);528	if (copied != count) {529		WARN_ON(1);530		dev_err(ourport->port.dev, "RxData copy to tty layer failed\n");531	}532}533 534static void s3c24xx_serial_stop_rx(struct uart_port *port)535{536	struct s3c24xx_uart_port *ourport = to_ourport(port);537	struct s3c24xx_uart_dma *dma = ourport->dma;538	struct tty_port *t = &port->state->port;539	struct dma_tx_state state;540	enum dma_status dma_status;541	unsigned int received;542 543	if (ourport->rx_enabled) {544		dev_dbg(port->dev, "stopping rx\n");545		switch (ourport->info->type) {546		case TYPE_S3C6400:547			s3c24xx_set_bit(port, S3C64XX_UINTM_RXD,548					S3C64XX_UINTM);549			break;550		case TYPE_APPLE_S5L:551			s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTHRESH_ENA, S3C2410_UCON);552			s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTO_ENA, S3C2410_UCON);553			s3c24xx_clear_bit(port, APPLE_S5L_UCON_RXTO_LEGACY_ENA, S3C2410_UCON);554			break;555		default:556			disable_irq_nosync(ourport->rx_irq);557			break;558		}559		ourport->rx_enabled = 0;560	}561	if (dma && dma->rx_chan) {562		dmaengine_pause(dma->tx_chan);563		dma_status = dmaengine_tx_status(dma->rx_chan,564				dma->rx_cookie, &state);565		if (dma_status == DMA_IN_PROGRESS ||566			dma_status == DMA_PAUSED) {567			received = dma->rx_bytes_requested - state.residue;568			dmaengine_terminate_all(dma->rx_chan);569			s3c24xx_uart_copy_rx_to_tty(ourport, t, received);570		}571	}572}573 574static inline const struct s3c24xx_uart_info575	*s3c24xx_port_to_info(struct uart_port *port)576{577	return to_ourport(port)->info;578}579 580static inline const struct s3c2410_uartcfg581	*s3c24xx_port_to_cfg(const struct uart_port *port)582{583	const struct s3c24xx_uart_port *ourport;584 585	if (port->dev == NULL)586		return NULL;587 588	ourport = container_of(port, struct s3c24xx_uart_port, port);589	return ourport->cfg;590}591 592static unsigned int593s3c24xx_serial_rx_fifocnt(const struct s3c24xx_uart_port *ourport, u32 ufstat)594{595	const struct s3c24xx_uart_info *info = ourport->info;596 597	if (ufstat & info->rx_fifofull)598		return ourport->port.fifosize;599 600	return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;601}602 603static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport);604static void s3c24xx_serial_rx_dma_complete(void *args)605{606	struct s3c24xx_uart_port *ourport = args;607	struct uart_port *port = &ourport->port;608 609	struct s3c24xx_uart_dma *dma = ourport->dma;610	struct tty_port *t = &port->state->port;611	struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);612 613	struct dma_tx_state state;614	unsigned long flags;615	int received;616 617	dmaengine_tx_status(dma->rx_chan,  dma->rx_cookie, &state);618	received  = dma->rx_bytes_requested - state.residue;619	async_tx_ack(dma->rx_desc);620 621	uart_port_lock_irqsave(port, &flags);622 623	if (received)624		s3c24xx_uart_copy_rx_to_tty(ourport, t, received);625 626	if (tty) {627		tty_flip_buffer_push(t);628		tty_kref_put(tty);629	}630 631	s3c64xx_start_rx_dma(ourport);632 633	uart_port_unlock_irqrestore(port, flags);634}635 636static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport)637{638	struct s3c24xx_uart_dma *dma = ourport->dma;639 640	dma_sync_single_for_device(dma->rx_chan->device->dev, dma->rx_addr,641				   dma->rx_size, DMA_FROM_DEVICE);642 643	dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan,644				dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM,645				DMA_PREP_INTERRUPT);646	if (!dma->rx_desc) {647		dev_err(ourport->port.dev, "Unable to get desc for Rx\n");648		return;649	}650 651	dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete;652	dma->rx_desc->callback_param = ourport;653	dma->rx_bytes_requested = dma->rx_size;654 655	dma->rx_cookie = dmaengine_submit(dma->rx_desc);656	dma_async_issue_pending(dma->rx_chan);657}658 659/* ? - where has parity gone?? */660#define S3C2410_UERSTAT_PARITY (0x1000)661 662static void enable_rx_dma(struct s3c24xx_uart_port *ourport)663{664	struct uart_port *port = &ourport->port;665	u32 ucon;666 667	/* set Rx mode to DMA mode */668	ucon = rd_regl(port, S3C2410_UCON);669	ucon &= ~(S3C64XX_UCON_RXBURST_MASK |670			S3C64XX_UCON_TIMEOUT_MASK |671			S3C64XX_UCON_EMPTYINT_EN |672			S3C64XX_UCON_DMASUS_EN |673			S3C64XX_UCON_TIMEOUT_EN |674			S3C64XX_UCON_RXMODE_MASK);675	ucon |= S3C64XX_UCON_RXBURST_1 |676			0xf << S3C64XX_UCON_TIMEOUT_SHIFT |677			S3C64XX_UCON_EMPTYINT_EN |678			S3C64XX_UCON_TIMEOUT_EN |679			S3C64XX_UCON_RXMODE_DMA;680	wr_regl(port, S3C2410_UCON, ucon);681 682	ourport->rx_mode = S3C24XX_RX_DMA;683}684 685static void enable_rx_pio(struct s3c24xx_uart_port *ourport)686{687	struct uart_port *port = &ourport->port;688	u32 ucon;689 690	/* set Rx mode to DMA mode */691	ucon = rd_regl(port, S3C2410_UCON);692	ucon &= ~S3C64XX_UCON_RXMODE_MASK;693	ucon |= S3C64XX_UCON_RXMODE_CPU;694 695	/* Apple types use these bits for IRQ masks */696	if (ourport->info->type != TYPE_APPLE_S5L) {697		ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK |698				S3C64XX_UCON_EMPTYINT_EN |699				S3C64XX_UCON_DMASUS_EN |700				S3C64XX_UCON_TIMEOUT_EN);701		ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |702				S3C64XX_UCON_TIMEOUT_EN;703	}704	wr_regl(port, S3C2410_UCON, ucon);705 706	ourport->rx_mode = S3C24XX_RX_PIO;707}708 709static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);710 711static irqreturn_t s3c24xx_serial_rx_chars_dma(struct s3c24xx_uart_port *ourport)712{713	struct uart_port *port = &ourport->port;714	struct s3c24xx_uart_dma *dma = ourport->dma;715	struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);716	struct tty_port *t = &port->state->port;717	struct dma_tx_state state;718	unsigned int received;719	u32 utrstat;720 721	utrstat = rd_regl(port, S3C2410_UTRSTAT);722	rd_regl(port, S3C2410_UFSTAT);723 724	uart_port_lock(port);725 726	if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) {727		s3c64xx_start_rx_dma(ourport);728		if (ourport->rx_mode == S3C24XX_RX_PIO)729			enable_rx_dma(ourport);730		goto finish;731	}732 733	if (ourport->rx_mode == S3C24XX_RX_DMA) {734		dmaengine_pause(dma->rx_chan);735		dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);736		dmaengine_terminate_all(dma->rx_chan);737		received = dma->rx_bytes_requested - state.residue;738		s3c24xx_uart_copy_rx_to_tty(ourport, t, received);739 740		enable_rx_pio(ourport);741	}742 743	s3c24xx_serial_rx_drain_fifo(ourport);744 745	if (tty) {746		tty_flip_buffer_push(t);747		tty_kref_put(tty);748	}749 750	wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT);751 752finish:753	uart_port_unlock(port);754 755	return IRQ_HANDLED;756}757 758static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)759{760	struct uart_port *port = &ourport->port;761	unsigned int max_count = port->fifosize;762	unsigned int fifocnt = 0;763	u32 ufcon, ufstat, uerstat;764	u8 ch, flag;765 766	while (max_count-- > 0) {767		/*768		 * Receive all characters known to be in FIFO769		 * before reading FIFO level again770		 */771		if (fifocnt == 0) {772			ufstat = rd_regl(port, S3C2410_UFSTAT);773			fifocnt = s3c24xx_serial_rx_fifocnt(ourport, ufstat);774			if (fifocnt == 0)775				break;776		}777		fifocnt--;778 779		uerstat = rd_regl(port, S3C2410_UERSTAT);780		ch = rd_reg(port, S3C2410_URXH);781 782		if (port->flags & UPF_CONS_FLOW) {783			bool txe = s3c24xx_serial_txempty_nofifo(port);784 785			if (ourport->rx_enabled) {786				if (!txe) {787					ourport->rx_enabled = 0;788					continue;789				}790			} else {791				if (txe) {792					ufcon = rd_regl(port, S3C2410_UFCON);793					ufcon |= S3C2410_UFCON_RESETRX;794					wr_regl(port, S3C2410_UFCON, ufcon);795					ourport->rx_enabled = 1;796					return;797				}798				continue;799			}800		}801 802		/* insert the character into the buffer */803 804		flag = TTY_NORMAL;805		port->icount.rx++;806 807		if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {808			dev_dbg(port->dev,809				"rxerr: port ch=0x%02x, rxs=0x%08x\n",810				ch, uerstat);811 812			/* check for break */813			if (uerstat & S3C2410_UERSTAT_BREAK) {814				dev_dbg(port->dev, "break!\n");815				port->icount.brk++;816				if (uart_handle_break(port))817					continue; /* Ignore character */818			}819 820			if (uerstat & S3C2410_UERSTAT_FRAME)821				port->icount.frame++;822			if (uerstat & S3C2410_UERSTAT_OVERRUN)823				port->icount.overrun++;824 825			uerstat &= port->read_status_mask;826 827			if (uerstat & S3C2410_UERSTAT_BREAK)828				flag = TTY_BREAK;829			else if (uerstat & S3C2410_UERSTAT_PARITY)830				flag = TTY_PARITY;831			else if (uerstat & (S3C2410_UERSTAT_FRAME |832					    S3C2410_UERSTAT_OVERRUN))833				flag = TTY_FRAME;834		}835 836		if (uart_handle_sysrq_char(port, ch))837			continue; /* Ignore character */838 839		uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,840				 ch, flag);841	}842 843	tty_flip_buffer_push(&port->state->port);844}845 846static irqreturn_t s3c24xx_serial_rx_chars_pio(struct s3c24xx_uart_port *ourport)847{848	struct uart_port *port = &ourport->port;849 850	uart_port_lock(port);851	s3c24xx_serial_rx_drain_fifo(ourport);852	uart_port_unlock(port);853 854	return IRQ_HANDLED;855}856 857static irqreturn_t s3c24xx_serial_rx_irq(struct s3c24xx_uart_port *ourport)858{859	if (ourport->dma && ourport->dma->rx_chan)860		return s3c24xx_serial_rx_chars_dma(ourport);861	return s3c24xx_serial_rx_chars_pio(ourport);862}863 864static void s3c24xx_serial_tx_chars(struct s3c24xx_uart_port *ourport)865{866	struct uart_port *port = &ourport->port;867	struct tty_port *tport = &port->state->port;868	unsigned int count, dma_count = 0, tail;869 870	count = kfifo_out_linear(&tport->xmit_fifo, &tail, UART_XMIT_SIZE);871 872	if (ourport->dma && ourport->dma->tx_chan &&873	    count >= ourport->min_dma_size) {874		int align = dma_get_cache_alignment() -875			(tail & (dma_get_cache_alignment() - 1));876		if (count - align >= ourport->min_dma_size) {877			dma_count = count - align;878			count = align;879			tail += align;880		}881	}882 883	if (port->x_char) {884		wr_reg(port, S3C2410_UTXH, port->x_char);885		port->icount.tx++;886		port->x_char = 0;887		return;888	}889 890	/* if there isn't anything more to transmit, or the uart is now891	 * stopped, disable the uart and exit892	 */893 894	if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) {895		s3c24xx_serial_stop_tx(port);896		return;897	}898 899	/* try and drain the buffer... */900 901	if (count > port->fifosize) {902		count = port->fifosize;903		dma_count = 0;904	}905 906	while (!(rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)) {907		unsigned char ch;908 909		if (!uart_fifo_get(port, &ch))910			break;911 912		wr_reg(port, S3C2410_UTXH, ch);913		count--;914	}915 916	if (!count && dma_count) {917		s3c24xx_serial_start_tx_dma(ourport, dma_count, tail);918		return;919	}920 921	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)922		uart_write_wakeup(port);923 924	if (kfifo_is_empty(&tport->xmit_fifo))925		s3c24xx_serial_stop_tx(port);926}927 928static irqreturn_t s3c24xx_serial_tx_irq(struct s3c24xx_uart_port *ourport)929{930	struct uart_port *port = &ourport->port;931 932	uart_port_lock(port);933 934	s3c24xx_serial_tx_chars(ourport);935 936	uart_port_unlock(port);937	return IRQ_HANDLED;938}939 940/* interrupt handler for s3c64xx and later SoC's.*/941static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id)942{943	struct s3c24xx_uart_port *ourport = id;944	const struct uart_port *port = &ourport->port;945	u32 pend = rd_regl(port, S3C64XX_UINTP);946	irqreturn_t ret = IRQ_HANDLED;947 948	if (pend & S3C64XX_UINTM_RXD_MSK) {949		ret = s3c24xx_serial_rx_irq(ourport);950		wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK);951	}952	if (pend & S3C64XX_UINTM_TXD_MSK) {953		ret = s3c24xx_serial_tx_irq(ourport);954		wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK);955	}956	return ret;957}958 959/* interrupt handler for Apple SoC's.*/960static irqreturn_t apple_serial_handle_irq(int irq, void *id)961{962	struct s3c24xx_uart_port *ourport = id;963	const struct uart_port *port = &ourport->port;964	u32 pend = rd_regl(port, S3C2410_UTRSTAT);965	irqreturn_t ret = IRQ_NONE;966 967	if (pend & (APPLE_S5L_UTRSTAT_RXTHRESH | APPLE_S5L_UTRSTAT_RXTO |968		APPLE_S5L_UTRSTAT_RXTO_LEGACY)) {969		wr_regl(port, S3C2410_UTRSTAT,970			APPLE_S5L_UTRSTAT_RXTHRESH | APPLE_S5L_UTRSTAT_RXTO |971			APPLE_S5L_UTRSTAT_RXTO_LEGACY);972		ret = s3c24xx_serial_rx_irq(ourport);973	}974	if (pend & APPLE_S5L_UTRSTAT_TXTHRESH) {975		wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_TXTHRESH);976		ret = s3c24xx_serial_tx_irq(ourport);977	}978 979	return ret;980}981 982static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)983{984	const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);985	u32 ufstat = rd_regl(port, S3C2410_UFSTAT);986	u32 ufcon = rd_regl(port, S3C2410_UFCON);987 988	if (ufcon & S3C2410_UFCON_FIFOMODE) {989		if ((ufstat & info->tx_fifomask) ||990		    (ufstat & info->tx_fifofull))991			return 0;992		return TIOCSER_TEMT;993	}994 995	return s3c24xx_serial_txempty_nofifo(port) ? TIOCSER_TEMT : 0;996}997 998/* no modem control lines */999static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)1000{1001	u32 umstat = rd_reg(port, S3C2410_UMSTAT);1002 1003	if (umstat & S3C2410_UMSTAT_CTS)1004		return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;1005	else1006		return TIOCM_CAR | TIOCM_DSR;1007}1008 1009static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)1010{1011	u32 umcon = rd_regl(port, S3C2410_UMCON);1012	u32 ucon = rd_regl(port, S3C2410_UCON);1013 1014	if (mctrl & TIOCM_RTS)1015		umcon |= S3C2410_UMCOM_RTS_LOW;1016	else1017		umcon &= ~S3C2410_UMCOM_RTS_LOW;1018 1019	wr_regl(port, S3C2410_UMCON, umcon);1020 1021	if (mctrl & TIOCM_LOOP)1022		ucon |= S3C2410_UCON_LOOPBACK;1023	else1024		ucon &= ~S3C2410_UCON_LOOPBACK;1025 1026	wr_regl(port, S3C2410_UCON, ucon);1027}1028 1029static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)1030{1031	unsigned long flags;1032	u32 ucon;1033 1034	uart_port_lock_irqsave(port, &flags);1035 1036	ucon = rd_regl(port, S3C2410_UCON);1037 1038	if (break_state)1039		ucon |= S3C2410_UCON_SBREAK;1040	else1041		ucon &= ~S3C2410_UCON_SBREAK;1042 1043	wr_regl(port, S3C2410_UCON, ucon);1044 1045	uart_port_unlock_irqrestore(port, flags);1046}1047 1048static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)1049{1050	struct s3c24xx_uart_dma	*dma = p->dma;1051	struct dma_slave_caps dma_caps;1052	const char *reason = NULL;1053	int ret;1054 1055	/* Default slave configuration parameters */1056	dma->rx_conf.direction		= DMA_DEV_TO_MEM;1057	dma->rx_conf.src_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;1058	dma->rx_conf.src_addr		= p->port.mapbase + S3C2410_URXH;1059	dma->rx_conf.src_maxburst	= 1;1060 1061	dma->tx_conf.direction		= DMA_MEM_TO_DEV;1062	dma->tx_conf.dst_addr_width	= DMA_SLAVE_BUSWIDTH_1_BYTE;1063	dma->tx_conf.dst_addr		= p->port.mapbase + S3C2410_UTXH;1064	dma->tx_conf.dst_maxburst	= 1;1065 1066	dma->rx_chan = dma_request_chan(p->port.dev, "rx");1067 1068	if (IS_ERR(dma->rx_chan)) {1069		reason = "DMA RX channel request failed";1070		ret = PTR_ERR(dma->rx_chan);1071		goto err_warn;1072	}1073 1074	ret = dma_get_slave_caps(dma->rx_chan, &dma_caps);1075	if (ret < 0 ||1076	    dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {1077		reason = "insufficient DMA RX engine capabilities";1078		ret = -EOPNOTSUPP;1079		goto err_release_rx;1080	}1081 1082	dmaengine_slave_config(dma->rx_chan, &dma->rx_conf);1083 1084	dma->tx_chan = dma_request_chan(p->port.dev, "tx");1085	if (IS_ERR(dma->tx_chan)) {1086		reason = "DMA TX channel request failed";1087		ret = PTR_ERR(dma->tx_chan);1088		goto err_release_rx;1089	}1090 1091	ret = dma_get_slave_caps(dma->tx_chan, &dma_caps);1092	if (ret < 0 ||1093	    dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {1094		reason = "insufficient DMA TX engine capabilities";1095		ret = -EOPNOTSUPP;1096		goto err_release_tx;1097	}1098 1099	dmaengine_slave_config(dma->tx_chan, &dma->tx_conf);1100 1101	/* RX buffer */1102	dma->rx_size = PAGE_SIZE;1103 1104	dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL);1105	if (!dma->rx_buf) {1106		ret = -ENOMEM;1107		goto err_release_tx;1108	}1109 1110	dma->rx_addr = dma_map_single(dma->rx_chan->device->dev, dma->rx_buf,1111				      dma->rx_size, DMA_FROM_DEVICE);1112	if (dma_mapping_error(dma->rx_chan->device->dev, dma->rx_addr)) {1113		reason = "DMA mapping error for RX buffer";1114		ret = -EIO;1115		goto err_free_rx;1116	}1117 1118	/* TX buffer */1119	dma->tx_addr = dma_map_single(dma->tx_chan->device->dev,1120				      p->port.state->port.xmit_buf,1121				      UART_XMIT_SIZE,1122				      DMA_TO_DEVICE);1123	if (dma_mapping_error(dma->tx_chan->device->dev, dma->tx_addr)) {1124		reason = "DMA mapping error for TX buffer";1125		ret = -EIO;1126		goto err_unmap_rx;1127	}1128 1129	return 0;1130 1131err_unmap_rx:1132	dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr,1133			 dma->rx_size, DMA_FROM_DEVICE);1134err_free_rx:1135	kfree(dma->rx_buf);1136err_release_tx:1137	dma_release_channel(dma->tx_chan);1138err_release_rx:1139	dma_release_channel(dma->rx_chan);1140err_warn:1141	if (reason)1142		dev_warn(p->port.dev, "%s, DMA will not be used\n", reason);1143	return ret;1144}1145 1146static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p)1147{1148	struct s3c24xx_uart_dma	*dma = p->dma;1149 1150	if (dma->rx_chan) {1151		dmaengine_terminate_all(dma->rx_chan);1152		dma_unmap_single(dma->rx_chan->device->dev, dma->rx_addr,1153				 dma->rx_size, DMA_FROM_DEVICE);1154		kfree(dma->rx_buf);1155		dma_release_channel(dma->rx_chan);1156		dma->rx_chan = NULL;1157	}1158 1159	if (dma->tx_chan) {1160		dmaengine_terminate_all(dma->tx_chan);1161		dma_unmap_single(dma->tx_chan->device->dev, dma->tx_addr,1162				 UART_XMIT_SIZE, DMA_TO_DEVICE);1163		dma_release_channel(dma->tx_chan);1164		dma->tx_chan = NULL;1165	}1166}1167 1168static void s3c64xx_serial_shutdown(struct uart_port *port)1169{1170	struct s3c24xx_uart_port *ourport = to_ourport(port);1171 1172	ourport->tx_enabled = 0;1173	ourport->tx_mode = 0;1174	ourport->rx_enabled = 0;1175 1176	free_irq(port->irq, ourport);1177 1178	wr_regl(port, S3C64XX_UINTP, 0xf);1179	wr_regl(port, S3C64XX_UINTM, 0xf);1180 1181	if (ourport->dma)1182		s3c24xx_serial_release_dma(ourport);1183 1184	ourport->tx_in_progress = 0;1185}1186 1187static void apple_s5l_serial_shutdown(struct uart_port *port)1188{1189	struct s3c24xx_uart_port *ourport = to_ourport(port);1190 1191	u32 ucon;1192 1193	ucon = rd_regl(port, S3C2410_UCON);1194	ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK |1195		  APPLE_S5L_UCON_RXTHRESH_ENA_MSK |1196		  APPLE_S5L_UCON_RXTO_ENA_MSK |1197		  APPLE_S5L_UCON_RXTO_LEGACY_ENA_MSK);1198	wr_regl(port, S3C2410_UCON, ucon);1199 1200	wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS);1201 1202	free_irq(port->irq, ourport);1203 1204	ourport->tx_enabled = 0;1205	ourport->tx_mode = 0;1206	ourport->rx_enabled = 0;1207 1208	if (ourport->dma)1209		s3c24xx_serial_release_dma(ourport);1210 1211	ourport->tx_in_progress = 0;1212}1213 1214static int s3c64xx_serial_startup(struct uart_port *port)1215{1216	struct s3c24xx_uart_port *ourport = to_ourport(port);1217	unsigned long flags;1218	u32 ufcon;1219	int ret;1220 1221	wr_regl(port, S3C64XX_UINTM, 0xf);1222	if (ourport->dma) {1223		ret = s3c24xx_serial_request_dma(ourport);1224		if (ret < 0) {1225			devm_kfree(port->dev, ourport->dma);1226			ourport->dma = NULL;1227		}1228	}1229 1230	ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED,1231			  s3c24xx_serial_portname(port), ourport);1232	if (ret) {1233		dev_err(port->dev, "cannot get irq %d\n", port->irq);1234		return ret;1235	}1236 1237	/* For compatibility with s3c24xx Soc's */1238	ourport->rx_enabled = 1;1239	ourport->tx_enabled = 0;1240 1241	uart_port_lock_irqsave(port, &flags);1242 1243	ufcon = rd_regl(port, S3C2410_UFCON);1244	ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;1245	if (!uart_console(port))1246		ufcon |= S3C2410_UFCON_RESETTX;1247	wr_regl(port, S3C2410_UFCON, ufcon);1248 1249	enable_rx_pio(ourport);1250 1251	uart_port_unlock_irqrestore(port, flags);1252 1253	/* Enable Rx Interrupt */1254	s3c24xx_clear_bit(port, S3C64XX_UINTM_RXD, S3C64XX_UINTM);1255 1256	return ret;1257}1258 1259static int apple_s5l_serial_startup(struct uart_port *port)1260{1261	struct s3c24xx_uart_port *ourport = to_ourport(port);1262	unsigned long flags;1263	u32 ufcon;1264	int ret;1265 1266	wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS);1267 1268	ret = request_irq(port->irq, apple_serial_handle_irq, 0,1269			  s3c24xx_serial_portname(port), ourport);1270	if (ret) {1271		dev_err(port->dev, "cannot get irq %d\n", port->irq);1272		return ret;1273	}1274 1275	/* For compatibility with s3c24xx Soc's */1276	ourport->rx_enabled = 1;1277	ourport->tx_enabled = 0;1278 1279	uart_port_lock_irqsave(port, &flags);1280 1281	ufcon = rd_regl(port, S3C2410_UFCON);1282	ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;1283	if (!uart_console(port))1284		ufcon |= S3C2410_UFCON_RESETTX;1285	wr_regl(port, S3C2410_UFCON, ufcon);1286 1287	enable_rx_pio(ourport);1288 1289	uart_port_unlock_irqrestore(port, flags);1290 1291	/* Enable Rx Interrupt */1292	s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTHRESH_ENA, S3C2410_UCON);1293	s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTO_ENA, S3C2410_UCON);1294	s3c24xx_set_bit(port, APPLE_S5L_UCON_RXTO_LEGACY_ENA, S3C2410_UCON);1295 1296	return ret;1297}1298 1299static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,1300			      unsigned int old)1301{1302	struct s3c24xx_uart_port *ourport = to_ourport(port);1303	int timeout = 10000;1304 1305	ourport->pm_level = level;1306 1307	switch (level) {1308	case 3:1309		while (--timeout && !s3c24xx_serial_txempty_nofifo(port))1310			udelay(100);1311 1312		if (!IS_ERR(ourport->baudclk))1313			clk_disable_unprepare(ourport->baudclk);1314 1315		clk_disable_unprepare(ourport->clk);1316		break;1317 1318	case 0:1319		clk_prepare_enable(ourport->clk);1320 1321		if (!IS_ERR(ourport->baudclk))1322			clk_prepare_enable(ourport->baudclk);1323		break;1324	default:1325		dev_err(port->dev, "s3c24xx_serial: unknown pm %d\n", level);1326	}1327}1328 1329/* baud rate calculation1330 *1331 * The UARTs on the S3C2410/S3C2440 can take their clocks from a number1332 * of different sources, including the peripheral clock ("pclk") and an1333 * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")1334 * with a programmable extra divisor.1335 *1336 * The following code goes through the clock sources, and calculates the1337 * baud clocks (and the resultant actual baud rates) and then tries to1338 * pick the closest one and select that.1339 *1340 */1341 1342#define MAX_CLK_NAME_LENGTH 151343 1344static inline u8 s3c24xx_serial_getsource(struct uart_port *port)1345{1346	const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);1347	u32 ucon;1348 1349	if (info->num_clks == 1)1350		return 0;1351 1352	ucon = rd_regl(port, S3C2410_UCON);1353	ucon &= info->clksel_mask;1354	return ucon >> info->clksel_shift;1355}1356 1357static void s3c24xx_serial_setsource(struct uart_port *port, u8 clk_sel)1358{1359	const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);1360	u32 ucon;1361 1362	if (info->num_clks == 1)1363		return;1364 1365	ucon = rd_regl(port, S3C2410_UCON);1366	if ((ucon & info->clksel_mask) >> info->clksel_shift == clk_sel)1367		return;1368 1369	ucon &= ~info->clksel_mask;1370	ucon |= clk_sel << info->clksel_shift;1371	wr_regl(port, S3C2410_UCON, ucon);1372}1373 1374static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport,1375			unsigned int req_baud, struct clk **best_clk,1376			u8 *clk_num)1377{1378	const struct s3c24xx_uart_info *info = ourport->info;1379	struct clk *clk;1380	unsigned long rate;1381	unsigned int baud, quot, best_quot = 0;1382	char clkname[MAX_CLK_NAME_LENGTH];1383	int calc_deviation, deviation = (1 << 30) - 1;1384	u8 cnt;1385 1386	for (cnt = 0; cnt < info->num_clks; cnt++) {1387		/* Keep selected clock if provided */1388		if (ourport->cfg->clk_sel &&1389			!(ourport->cfg->clk_sel & (1 << cnt)))1390			continue;1391 1392		sprintf(clkname, "clk_uart_baud%d", cnt);1393		clk = clk_get(ourport->port.dev, clkname);1394		if (IS_ERR(clk))1395			continue;1396 1397		rate = clk_get_rate(clk);1398		if (!rate) {1399			dev_err(ourport->port.dev,1400				"Failed to get clock rate for %s.\n", clkname);1401			clk_put(clk);1402			continue;1403		}1404 1405		if (ourport->info->has_divslot) {1406			unsigned long div = rate / req_baud;1407 1408			/* The UDIVSLOT register on the newer UARTs allows us to1409			 * get a divisor adjustment of 1/16th on the baud clock.1410			 *1411			 * We don't keep the UDIVSLOT value (the 16ths we1412			 * calculated by not multiplying the baud by 16) as it1413			 * is easy enough to recalculate.1414			 */1415 1416			quot = div / 16;1417			baud = rate / div;1418		} else {1419			quot = (rate + (8 * req_baud)) / (16 * req_baud);1420			baud = rate / (quot * 16);1421		}1422		quot--;1423 1424		calc_deviation = abs(req_baud - baud);1425 1426		if (calc_deviation < deviation) {1427			/*1428			 * If we find a better clk, release the previous one, if1429			 * any.1430			 */1431			if (!IS_ERR(*best_clk))1432				clk_put(*best_clk);1433			*best_clk = clk;1434			best_quot = quot;1435			*clk_num = cnt;1436			deviation = calc_deviation;1437		} else {1438			clk_put(clk);1439		}1440	}1441 1442	return best_quot;1443}1444 1445/* udivslot_table[]1446 *1447 * This table takes the fractional value of the baud divisor and gives1448 * the recommended setting for the UDIVSLOT register.1449 */1450static const u16 udivslot_table[16] = {1451	[0] = 0x0000,1452	[1] = 0x0080,1453	[2] = 0x0808,1454	[3] = 0x0888,1455	[4] = 0x2222,1456	[5] = 0x4924,1457	[6] = 0x4A52,1458	[7] = 0x54AA,1459	[8] = 0x5555,1460	[9] = 0xD555,1461	[10] = 0xD5D5,1462	[11] = 0xDDD5,1463	[12] = 0xDDDD,1464	[13] = 0xDFDD,1465	[14] = 0xDFDF,1466	[15] = 0xFFDF,1467};1468 1469static void s3c24xx_serial_set_termios(struct uart_port *port,1470				       struct ktermios *termios,1471				       const struct ktermios *old)1472{1473	const struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);1474	struct s3c24xx_uart_port *ourport = to_ourport(port);1475	struct clk *clk = ERR_PTR(-EINVAL);1476	unsigned long flags;1477	unsigned int baud, quot;1478	unsigned int udivslot = 0;1479	u32 ulcon, umcon;1480	u8 clk_sel = 0;1481 1482	/*1483	 * We don't support modem control lines.1484	 */1485	termios->c_cflag &= ~(HUPCL | CMSPAR);1486	termios->c_cflag |= CLOCAL;1487 1488	/*1489	 * Ask the core to calculate the divisor for us.1490	 */1491 1492	baud = uart_get_baud_rate(port, termios, old, 0, 3000000);1493	quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel);1494	if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)1495		quot = port->custom_divisor;1496	if (IS_ERR(clk))1497		return;1498 1499	/* check to see if we need  to change clock source */1500 1501	if (ourport->baudclk != clk) {1502		clk_prepare_enable(clk);1503 1504		s3c24xx_serial_setsource(port, clk_sel);1505 1506		if (!IS_ERR(ourport->baudclk)) {1507			clk_disable_unprepare(ourport->baudclk);1508			ourport->baudclk = ERR_PTR(-EINVAL);1509		}1510 1511		ourport->baudclk = clk;1512		ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;1513	}1514 1515	if (ourport->info->has_divslot) {1516		unsigned int div = ourport->baudclk_rate / baud;1517 1518		if (cfg->has_fracval) {1519			udivslot = (div & 15);1520			dev_dbg(port->dev, "fracval = %04x\n", udivslot);1521		} else {1522			udivslot = udivslot_table[div & 15];1523			dev_dbg(port->dev, "udivslot = %04x (div %d)\n",1524				udivslot, div & 15);1525		}1526	}1527 1528	switch (termios->c_cflag & CSIZE) {1529	case CS5:1530		dev_dbg(port->dev, "config: 5bits/char\n");1531		ulcon = S3C2410_LCON_CS5;1532		break;1533	case CS6:1534		dev_dbg(port->dev, "config: 6bits/char\n");1535		ulcon = S3C2410_LCON_CS6;1536		break;1537	case CS7:1538		dev_dbg(port->dev, "config: 7bits/char\n");1539		ulcon = S3C2410_LCON_CS7;1540		break;1541	case CS8:1542	default:1543		dev_dbg(port->dev, "config: 8bits/char\n");1544		ulcon = S3C2410_LCON_CS8;1545		break;1546	}1547 1548	/* preserve original lcon IR settings */1549	ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);1550 1551	if (termios->c_cflag & CSTOPB)1552		ulcon |= S3C2410_LCON_STOPB;1553 1554	if (termios->c_cflag & PARENB) {1555		if (termios->c_cflag & PARODD)1556			ulcon |= S3C2410_LCON_PODD;1557		else1558			ulcon |= S3C2410_LCON_PEVEN;1559	} else {1560		ulcon |= S3C2410_LCON_PNONE;1561	}1562 1563	uart_port_lock_irqsave(port, &flags);1564 1565	dev_dbg(port->dev,1566		"setting ulcon to %08x, brddiv to %d, udivslot %08x\n",1567		ulcon, quot, udivslot);1568 1569	wr_regl(port, S3C2410_ULCON, ulcon);1570	wr_regl(port, S3C2410_UBRDIV, quot);1571 1572	port->status &= ~UPSTAT_AUTOCTS;1573 1574	umcon = rd_regl(port, S3C2410_UMCON);1575	if (termios->c_cflag & CRTSCTS) {1576		umcon |= S3C2410_UMCOM_AFC;1577		/* Disable RTS when RX FIFO contains 63 bytes */1578		umcon &= ~S3C2412_UMCON_AFC_8;1579		port->status = UPSTAT_AUTOCTS;1580	} else {1581		umcon &= ~S3C2410_UMCOM_AFC;1582	}1583	wr_regl(port, S3C2410_UMCON, umcon);1584 1585	if (ourport->info->has_divslot)1586		wr_regl(port, S3C2443_DIVSLOT, udivslot);1587 1588	dev_dbg(port->dev,1589		"uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",1590		rd_regl(port, S3C2410_ULCON),1591		rd_regl(port, S3C2410_UCON),1592		rd_regl(port, S3C2410_UFCON));1593 1594	/*1595	 * Update the per-port timeout.1596	 */1597	uart_update_timeout(port, termios->c_cflag, baud);1598 1599	/*1600	 * Which character status flags are we interested in?1601	 */1602	port->read_status_mask = S3C2410_UERSTAT_OVERRUN;1603	if (termios->c_iflag & INPCK)1604		port->read_status_mask |= S3C2410_UERSTAT_FRAME |1605			S3C2410_UERSTAT_PARITY;1606	/*1607	 * Which character status flags should we ignore?1608	 */1609	port->ignore_status_mask = 0;1610	if (termios->c_iflag & IGNPAR)1611		port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;1612	if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)1613		port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;1614 1615	/*1616	 * Ignore all characters if CREAD is not set.1617	 */1618	if ((termios->c_cflag & CREAD) == 0)1619		port->ignore_status_mask |= RXSTAT_DUMMY_READ;1620 1621	uart_port_unlock_irqrestore(port, flags);1622}1623 1624static const char *s3c24xx_serial_type(struct uart_port *port)1625{1626	const struct s3c24xx_uart_port *ourport = to_ourport(port);1627 1628	switch (ourport->info->type) {1629	case TYPE_S3C6400:1630		return "S3C6400/10";1631	case TYPE_APPLE_S5L:1632		return "APPLE S5L";1633	default:1634		return NULL;1635	}1636}1637 1638static void s3c24xx_serial_config_port(struct uart_port *port, int flags)1639{1640	const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);1641 1642	if (flags & UART_CONFIG_TYPE)1643		port->type = info->port_type;1644}1645 1646/*1647 * verify the new serial_struct (for TIOCSSERIAL).1648 */1649static int1650s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)1651{1652	const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);1653 1654	if (ser->type != PORT_UNKNOWN && ser->type != info->port_type)1655		return -EINVAL;1656 1657	return 0;1658}1659 1660#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE1661 1662static struct console s3c24xx_serial_console;1663 1664static void __init s3c24xx_serial_register_console(void)1665{1666	register_console(&s3c24xx_serial_console);1667}1668 1669static void s3c24xx_serial_unregister_console(void)1670{1671	if (console_is_registered(&s3c24xx_serial_console))1672		unregister_console(&s3c24xx_serial_console);1673}1674 1675#define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console1676#else1677static inline void s3c24xx_serial_register_console(void) { }1678static inline void s3c24xx_serial_unregister_console(void) { }1679#define S3C24XX_SERIAL_CONSOLE NULL1680#endif1681 1682#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)1683static int s3c24xx_serial_get_poll_char(struct uart_port *port);1684static void s3c24xx_serial_put_poll_char(struct uart_port *port,1685			 unsigned char c);1686#endif1687 1688static const struct uart_ops s3c64xx_serial_ops = {1689	.pm		= s3c24xx_serial_pm,1690	.tx_empty	= s3c24xx_serial_tx_empty,1691	.get_mctrl	= s3c24xx_serial_get_mctrl,1692	.set_mctrl	= s3c24xx_serial_set_mctrl,1693	.stop_tx	= s3c24xx_serial_stop_tx,1694	.start_tx	= s3c24xx_serial_start_tx,1695	.stop_rx	= s3c24xx_serial_stop_rx,1696	.break_ctl	= s3c24xx_serial_break_ctl,1697	.startup	= s3c64xx_serial_startup,1698	.shutdown	= s3c64xx_serial_shutdown,1699	.set_termios	= s3c24xx_serial_set_termios,1700	.type		= s3c24xx_serial_type,1701	.config_port	= s3c24xx_serial_config_port,1702	.verify_port	= s3c24xx_serial_verify_port,1703#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)1704	.poll_get_char = s3c24xx_serial_get_poll_char,1705	.poll_put_char = s3c24xx_serial_put_poll_char,1706#endif1707};1708 1709static const struct uart_ops apple_s5l_serial_ops = {1710	.pm		= s3c24xx_serial_pm,1711	.tx_empty	= s3c24xx_serial_tx_empty,1712	.get_mctrl	= s3c24xx_serial_get_mctrl,1713	.set_mctrl	= s3c24xx_serial_set_mctrl,1714	.stop_tx	= s3c24xx_serial_stop_tx,1715	.start_tx	= s3c24xx_serial_start_tx,1716	.stop_rx	= s3c24xx_serial_stop_rx,1717	.break_ctl	= s3c24xx_serial_break_ctl,1718	.startup	= apple_s5l_serial_startup,1719	.shutdown	= apple_s5l_serial_shutdown,1720	.set_termios	= s3c24xx_serial_set_termios,1721	.type		= s3c24xx_serial_type,1722	.config_port	= s3c24xx_serial_config_port,1723	.verify_port	= s3c24xx_serial_verify_port,1724#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)1725	.poll_get_char = s3c24xx_serial_get_poll_char,1726	.poll_put_char = s3c24xx_serial_put_poll_char,1727#endif1728};1729 1730static struct uart_driver s3c24xx_uart_drv = {1731	.owner		= THIS_MODULE,1732	.driver_name	= "s3c2410_serial",1733	.nr		= UART_NR,1734	.cons		= S3C24XX_SERIAL_CONSOLE,1735	.dev_name	= S3C24XX_SERIAL_NAME,1736	.major		= S3C24XX_SERIAL_MAJOR,1737	.minor		= S3C24XX_SERIAL_MINOR,1738};1739 1740static struct s3c24xx_uart_port s3c24xx_serial_ports[UART_NR];1741 1742static void s3c24xx_serial_init_port_default(int index)1743{1744	struct uart_port *port = &s3c24xx_serial_ports[index].port;1745 1746	spin_lock_init(&port->lock);1747 1748	port->uartclk = 0;1749	port->fifosize = 16;1750	port->flags = UPF_BOOT_AUTOCONF;1751	port->line = index;1752}1753 1754/* s3c24xx_serial_resetport1755 *1756 * reset the fifos and other the settings.1757 */1758 1759static void s3c24xx_serial_resetport(struct uart_port *port,1760				     const struct s3c2410_uartcfg *cfg)1761{1762	const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);1763	u32 ucon = rd_regl(port, S3C2410_UCON);1764 1765	ucon &= (info->clksel_mask | info->ucon_mask);1766	wr_regl(port, S3C2410_UCON, ucon | cfg->ucon);1767 1768	/* reset both fifos */1769	wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);1770	wr_regl(port, S3C2410_UFCON, cfg->ufcon);1771 1772	/* some delay is required after fifo reset */1773	udelay(1);1774}1775 1776static int s3c24xx_serial_enable_baudclk(struct s3c24xx_uart_port *ourport)1777{1778	struct device *dev = ourport->port.dev;1779	const struct s3c24xx_uart_info *info = ourport->info;1780	char clk_name[MAX_CLK_NAME_LENGTH];1781	struct clk *clk;1782	int ret;1783	u8 clk_sel, clk_num;1784 1785	clk_sel = ourport->cfg->clk_sel ? : info->def_clk_sel;1786	for (clk_num = 0; clk_num < info->num_clks; clk_num++) {1787		if (!(clk_sel & (1 << clk_num)))1788			continue;1789 1790		sprintf(clk_name, "clk_uart_baud%d", clk_num);1791		clk = clk_get(dev, clk_name);1792		if (IS_ERR(clk))1793			continue;1794 1795		ret = clk_prepare_enable(clk);1796		if (ret) {1797			clk_put(clk);1798			continue;1799		}1800 1801		ourport->baudclk = clk;1802		ourport->baudclk_rate = clk_get_rate(clk);1803		s3c24xx_serial_setsource(&ourport->port, clk_num);1804 1805		return 0;1806	}1807 1808	return -EINVAL;1809}1810 1811/* s3c24xx_serial_init_port1812 *1813 * initialise a single serial port from the platform device given1814 */1815 1816static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,1817				    struct platform_device *platdev)1818{1819	struct uart_port *port = &ourport->port;1820	const struct s3c2410_uartcfg *cfg = ourport->cfg;1821	struct resource *res;1822	int ret;1823 1824	if (platdev == NULL)1825		return -ENODEV;1826 1827	if (port->mapbase != 0)1828		return -EINVAL;1829 1830	/* setup info for port */1831	port->dev	= &platdev->dev;1832 1833	port->uartclk = 1;1834 1835	if (cfg->uart_flags & UPF_CONS_FLOW) {1836		dev_dbg(port->dev, "enabling flow control\n");1837		port->flags |= UPF_CONS_FLOW;1838	}1839 1840	/* sort our the physical and virtual addresses for each UART */1841 1842	res = platform_get_resource(platdev, IORESOURCE_MEM, 0);1843	if (res == NULL) {1844		dev_err(port->dev, "failed to find memory resource for uart\n");1845		return -EINVAL;1846	}1847 1848	dev_dbg(port->dev, "resource %pR)\n", res);1849 1850	port->membase = devm_ioremap_resource(port->dev, res);1851	if (IS_ERR(port->membase)) {1852		dev_err(port->dev, "failed to remap controller address\n");1853		return -EBUSY;1854	}1855 1856	port->mapbase = res->start;1857	ret = platform_get_irq(platdev, 0);1858	if (ret < 0) {1859		port->irq = 0;1860	} else {1861		port->irq = ret;1862		ourport->rx_irq = ret;1863		ourport->tx_irq = ret + 1;1864	}1865 1866	/*1867	 * DMA is currently supported only on DT platforms, if DMA properties1868	 * are specified.1869	 */1870	if (platdev->dev.of_node && of_find_property(platdev->dev.of_node,1871						     "dmas", NULL)) {1872		ourport->dma = devm_kzalloc(port->dev,1873					    sizeof(*ourport->dma),1874					    GFP_KERNEL);1875		if (!ourport->dma) {1876			ret = -ENOMEM;1877			goto err;1878		}1879	}1880 1881	ourport->clk	= clk_get(&platdev->dev, "uart");1882	if (IS_ERR(ourport->clk)) {1883		pr_err("%s: Controller clock not found\n",1884				dev_name(&platdev->dev));1885		ret = PTR_ERR(ourport->clk);1886		goto err;1887	}1888 1889	ret = clk_prepare_enable(ourport->clk);1890	if (ret) {1891		pr_err("uart: clock failed to prepare+enable: %d\n", ret);1892		clk_put(ourport->clk);1893		goto err;1894	}1895 1896	ret = s3c24xx_serial_enable_baudclk(ourport);1897	if (ret)1898		pr_warn("uart: failed to enable baudclk\n");1899 1900	/* Keep all interrupts masked and cleared */1901	switch (ourport->info->type) {1902	case TYPE_S3C6400:1903		wr_regl(port, S3C64XX_UINTM, 0xf);1904		wr_regl(port, S3C64XX_UINTP, 0xf);1905		wr_regl(port, S3C64XX_UINTSP, 0xf);1906		break;1907	case TYPE_APPLE_S5L: {1908		u32 ucon;1909 1910		ucon = rd_regl(port, S3C2410_UCON);1911		ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK |1912			APPLE_S5L_UCON_RXTHRESH_ENA_MSK |1913			APPLE_S5L_UCON_RXTO_ENA_MSK);1914		wr_regl(port, S3C2410_UCON, ucon);1915 1916		wr_regl(port, S3C2410_UTRSTAT, APPLE_S5L_UTRSTAT_ALL_FLAGS);1917		break;1918	}1919	default:1920		break;1921	}1922 1923	dev_dbg(port->dev, "port: map=%pa, mem=%p, irq=%d (%d,%d), clock=%u\n",1924		&port->mapbase, port->membase, port->irq,1925		ourport->rx_irq, ourport->tx_irq, port->uartclk);1926 1927	/* reset the fifos (and setup the uart) */1928	s3c24xx_serial_resetport(port, cfg);1929 1930	return 0;1931 1932err:1933	port->mapbase = 0;1934	return ret;1935}1936 1937/* Device driver serial port probe */1938 1939static int probe_index;1940 1941static inline const struct s3c24xx_serial_drv_data *1942s3c24xx_get_driver_data(struct platform_device *pdev)1943{1944	if (dev_of_node(&pdev->dev))1945		return of_device_get_match_data(&pdev->dev);1946 1947	return (struct s3c24xx_serial_drv_data *)1948			platform_get_device_id(pdev)->driver_data;1949}1950 1951static int s3c24xx_serial_probe(struct platform_device *pdev)1952{1953	struct device_node *np = pdev->dev.of_node;1954	struct s3c24xx_uart_port *ourport;1955	int index = probe_index;1956	int ret, prop = 0, fifosize_prop = 1;1957 1958	if (np) {1959		ret = of_alias_get_id(np, "serial");1960		if (ret >= 0)1961			index = ret;1962	}1963 1964	if (index >= ARRAY_SIZE(s3c24xx_serial_ports)) {1965		dev_err(&pdev->dev, "serial%d out of range\n", index);1966		return -EINVAL;1967	}1968	ourport = &s3c24xx_serial_ports[index];1969 1970	s3c24xx_serial_init_port_default(index);1971 1972	ourport->drv_data = s3c24xx_get_driver_data(pdev);1973	if (!ourport->drv_data) {1974		dev_err(&pdev->dev, "could not find driver data\n");1975		return -ENODEV;1976	}1977 1978	ourport->baudclk = ERR_PTR(-EINVAL);1979	ourport->info = &ourport->drv_data->info;1980	ourport->cfg = (dev_get_platdata(&pdev->dev)) ?1981			dev_get_platdata(&pdev->dev) :1982			&ourport->drv_data->def_cfg;1983 1984	switch (ourport->info->type) {1985	case TYPE_S3C6400:1986		ourport->port.ops = &s3c64xx_serial_ops;1987		break;1988	case TYPE_APPLE_S5L:1989		ourport->port.ops = &apple_s5l_serial_ops;1990		break;1991	}1992 1993	ourport->port.iotype = ourport->info->iotype;1994 1995	if (np) {1996		fifosize_prop = of_property_read_u32(np, "samsung,uart-fifosize",1997				&ourport->port.fifosize);1998 1999		if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {2000			switch (prop) {2001			case 1:2002				ourport->port.iotype = UPIO_MEM;2003				break;2004			case 4:2005				ourport->port.iotype = UPIO_MEM32;2006				break;2007			default:2008				dev_warn(&pdev->dev, "unsupported reg-io-width (%d)\n",2009						prop);2010				return -EINVAL;2011			}2012		}2013	}2014 2015	if (fifosize_prop) {2016		if (ourport->drv_data->fifosize[index])2017			ourport->port.fifosize = ourport->drv_data->fifosize[index];2018		else if (ourport->info->fifosize)2019			ourport->port.fifosize = ourport->info->fifosize;2020	}2021 2022	ourport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_SAMSUNG_CONSOLE);2023 2024	/*2025	 * DMA transfers must be aligned at least to cache line size,2026	 * so find minimal transfer size suitable for DMA mode2027	 */2028	ourport->min_dma_size = max_t(int, ourport->port.fifosize,2029				    dma_get_cache_alignment());2030 2031	dev_dbg(&pdev->dev, "%s: initialising port %p...\n", __func__, ourport);2032 2033	ret = s3c24xx_serial_init_port(ourport, pdev);2034	if (ret < 0)2035		return ret;2036 2037	if (!s3c24xx_uart_drv.state) {2038		ret = uart_register_driver(&s3c24xx_uart_drv);2039		if (ret < 0) {2040			pr_err("Failed to register Samsung UART driver\n");2041			return ret;2042		}2043	}2044 2045	dev_dbg(&pdev->dev, "%s: adding port\n", __func__);2046	uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);2047	platform_set_drvdata(pdev, &ourport->port);2048 2049	/*2050	 * Deactivate the clock enabled in s3c24xx_serial_init_port here,2051	 * so that a potential re-enablement through the pm-callback overlaps2052	 * and keeps the clock enabled in this case.2053	 */2054	clk_disable_unprepare(ourport->clk);2055	if (!IS_ERR(ourport->baudclk))2056		clk_disable_unprepare(ourport->baudclk);2057 2058	probe_index++;2059 2060	return 0;2061}2062 2063static void s3c24xx_serial_remove(struct platform_device *dev)2064{2065	struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);2066 2067	if (port)2068		uart_remove_one_port(&s3c24xx_uart_drv, port);2069 2070	uart_unregister_driver(&s3c24xx_uart_drv);2071}2072 2073/* UART power management code */2074#ifdef CONFIG_PM_SLEEP2075static int s3c24xx_serial_suspend(struct device *dev)2076{2077	struct uart_port *port = s3c24xx_dev_to_port(dev);2078 2079	if (port)2080		uart_suspend_port(&s3c24xx_uart_drv, port);2081 2082	return 0;2083}2084 2085static int s3c24xx_serial_resume(struct device *dev)2086{2087	struct uart_port *port = s3c24xx_dev_to_port(dev);2088	struct s3c24xx_uart_port *ourport = to_ourport(port);2089 2090	if (port) {2091		clk_prepare_enable(ourport->clk);2092		if (!IS_ERR(ourport->baudclk))2093			clk_prepare_enable(ourport->baudclk);2094		s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));2095		if (!IS_ERR(ourport->baudclk))2096			clk_disable_unprepare(ourport->baudclk);2097		clk_disable_unprepare(ourport->clk);2098 2099		uart_resume_port(&s3c24xx_uart_drv, port);2100	}2101 2102	return 0;2103}2104 2105static int s3c24xx_serial_resume_noirq(struct device *dev)2106{2107	struct uart_port *port = s3c24xx_dev_to_port(dev);2108	struct s3c24xx_uart_port *ourport = to_ourport(port);2109 2110	if (port) {2111		/* restore IRQ mask */2112		switch (ourport->info->type) {2113		case TYPE_S3C6400: {2114			u32 uintm = 0xf;2115 2116			if (ourport->tx_enabled)2117				uintm &= ~S3C64XX_UINTM_TXD_MSK;2118			if (ourport->rx_enabled)2119				uintm &= ~S3C64XX_UINTM_RXD_MSK;2120			clk_prepare_enable(ourport->clk);2121			if (!IS_ERR(ourport->baudclk))2122				clk_prepare_enable(ourport->baudclk);2123			wr_regl(port, S3C64XX_UINTM, uintm);2124			if (!IS_ERR(ourport->baudclk))2125				clk_disable_unprepare(ourport->baudclk);2126			clk_disable_unprepare(ourport->clk);2127			break;2128		}2129		case TYPE_APPLE_S5L: {2130			u32 ucon;2131			int ret;2132 2133			ret = clk_prepare_enable(ourport->clk);2134			if (ret) {2135				dev_err(dev, "clk_enable clk failed: %d\n", ret);2136				return ret;2137			}2138			if (!IS_ERR(ourport->baudclk)) {2139				ret = clk_prepare_enable(ourport->baudclk);2140				if (ret) {2141					dev_err(dev, "clk_enable baudclk failed: %d\n", ret);2142					clk_disable_unprepare(ourport->clk);2143					return ret;2144				}2145			}2146 2147			ucon = rd_regl(port, S3C2410_UCON);2148 2149			ucon &= ~(APPLE_S5L_UCON_TXTHRESH_ENA_MSK |2150				  APPLE_S5L_UCON_RXTHRESH_ENA_MSK |2151				  APPLE_S5L_UCON_RXTO_ENA_MSK |2152				  APPLE_S5L_UCON_RXTO_LEGACY_ENA_MSK);2153 2154			if (ourport->tx_enabled)2155				ucon |= APPLE_S5L_UCON_TXTHRESH_ENA_MSK;2156			if (ourport->rx_enabled)2157				ucon |= APPLE_S5L_UCON_RXTHRESH_ENA_MSK |2158					APPLE_S5L_UCON_RXTO_ENA_MSK |2159					APPLE_S5L_UCON_RXTO_LEGACY_ENA_MSK;2160 2161			wr_regl(port, S3C2410_UCON, ucon);2162 2163			if (!IS_ERR(ourport->baudclk))2164				clk_disable_unprepare(ourport->baudclk);2165			clk_disable_unprepare(ourport->clk);2166			break;2167		}2168		default:2169			break;2170		}2171	}2172 2173	return 0;2174}2175 2176static const struct dev_pm_ops s3c24xx_serial_pm_ops = {2177	SET_SYSTEM_SLEEP_PM_OPS(s3c24xx_serial_suspend, s3c24xx_serial_resume)2178	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(NULL, s3c24xx_serial_resume_noirq)2179};2180#define SERIAL_SAMSUNG_PM_OPS	(&s3c24xx_serial_pm_ops)2181 2182#else /* !CONFIG_PM_SLEEP */2183 2184#define SERIAL_SAMSUNG_PM_OPS	NULL2185#endif /* CONFIG_PM_SLEEP */2186 2187/* Console code */2188 2189#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE2190 2191static struct uart_port *cons_uart;2192 2193static bool2194s3c24xx_serial_console_txrdy(struct uart_port *port, u32 ufcon)2195{2196	const struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);2197	u32 ufstat, utrstat;2198 2199	if (ufcon & S3C2410_UFCON_FIFOMODE) {2200		/* fifo mode - check amount of data in fifo registers... */2201 2202		ufstat = rd_regl(port, S3C2410_UFSTAT);2203		return !(ufstat & info->tx_fifofull);2204	}2205 2206	/* in non-fifo mode, we go and use the tx buffer empty */2207 2208	utrstat = rd_regl(port, S3C2410_UTRSTAT);2209	return utrstat & S3C2410_UTRSTAT_TXE;2210}2211 2212static bool2213s3c24xx_port_configured(u32 ucon)2214{2215	/* consider the serial port configured if the tx/rx mode set */2216	return (ucon & 0xf) != 0;2217}2218 2219#ifdef CONFIG_CONSOLE_POLL2220/*2221 * Console polling routines for writing and reading from the uart while2222 * in an interrupt or debug context.2223 */2224 2225static int s3c24xx_serial_get_poll_char(struct uart_port *port)2226{2227	const struct s3c24xx_uart_port *ourport = to_ourport(port);2228	u32 ufstat;2229 2230	ufstat = rd_regl(port, S3C2410_UFSTAT);2231	if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)2232		return NO_POLL_CHAR;2233 2234	return rd_reg(port, S3C2410_URXH);2235}2236 2237static void s3c24xx_serial_put_poll_char(struct uart_port *port,2238		unsigned char c)2239{2240	u32 ufcon = rd_regl(port, S3C2410_UFCON);2241	u32 ucon = rd_regl(port, S3C2410_UCON);2242 2243	/* not possible to xmit on unconfigured port */2244	if (!s3c24xx_port_configured(ucon))2245		return;2246 2247	while (!s3c24xx_serial_console_txrdy(port, ufcon))2248		cpu_relax();2249	wr_reg(port, S3C2410_UTXH, c);2250}2251 2252#endif /* CONFIG_CONSOLE_POLL */2253 2254static void2255s3c24xx_serial_console_putchar(struct uart_port *port, unsigned char ch)2256{2257	u32 ufcon = rd_regl(port, S3C2410_UFCON);2258 2259	while (!s3c24xx_serial_console_txrdy(port, ufcon))2260		cpu_relax();2261	wr_reg(port, S3C2410_UTXH, ch);2262}2263 2264static void2265s3c24xx_serial_console_write(struct console *co, const char *s,2266			     unsigned int count)2267{2268	u32 ucon = rd_regl(cons_uart, S3C2410_UCON);2269	unsigned long flags;2270	bool locked = true;2271 2272	/* not possible to xmit on unconfigured port */2273	if (!s3c24xx_port_configured(ucon))2274		return;2275 2276	if (cons_uart->sysrq)2277		locked = false;2278	else if (oops_in_progress)2279		locked = uart_port_trylock_irqsave(cons_uart, &flags);2280	else2281		uart_port_lock_irqsave(cons_uart, &flags);2282 2283	uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);2284 2285	if (locked)2286		uart_port_unlock_irqrestore(cons_uart, flags);2287}2288 2289/* Shouldn't be __init, as it can be instantiated from other module */2290static void2291s3c24xx_serial_get_options(struct uart_port *port, int *baud,2292			   int *parity, int *bits)2293{2294	struct clk *clk;2295	unsigned long rate;2296	u32 ulcon, ucon, ubrdiv;2297	char clk_name[MAX_CLK_NAME_LENGTH];2298	u8 clk_sel;2299 2300	ulcon  = rd_regl(port, S3C2410_ULCON);2301	ucon   = rd_regl(port, S3C2410_UCON);2302	ubrdiv = rd_regl(port, S3C2410_UBRDIV);2303 2304	if (s3c24xx_port_configured(ucon)) {2305		switch (ulcon & S3C2410_LCON_CSMASK) {2306		case S3C2410_LCON_CS5:2307			*bits = 5;2308			break;2309		case S3C2410_LCON_CS6:2310			*bits = 6;2311			break;2312		case S3C2410_LCON_CS7:2313			*bits = 7;2314			break;2315		case S3C2410_LCON_CS8:2316		default:2317			*bits = 8;2318			break;2319		}2320 2321		switch (ulcon & S3C2410_LCON_PMASK) {2322		case S3C2410_LCON_PEVEN:2323			*parity = 'e';2324			break;2325 2326		case S3C2410_LCON_PODD:2327			*parity = 'o';2328			break;2329 2330		case S3C2410_LCON_PNONE:2331		default:2332			*parity = 'n';2333		}2334 2335		/* now calculate the baud rate */2336 2337		clk_sel = s3c24xx_serial_getsource(port);2338		sprintf(clk_name, "clk_uart_baud%d", clk_sel);2339 2340		clk = clk_get(port->dev, clk_name);2341		if (!IS_ERR(clk))2342			rate = clk_get_rate(clk);2343		else2344			rate = 1;2345 2346		*baud = rate / (16 * (ubrdiv + 1));2347		dev_dbg(port->dev, "calculated baud %d\n", *baud);2348	}2349}2350 2351/* Shouldn't be __init, as it can be instantiated from other module */2352static int2353s3c24xx_serial_console_setup(struct console *co, char *options)2354{2355	struct uart_port *port;2356	int baud = 9600;2357	int bits = 8;2358	int parity = 'n';2359	int flow = 'n';2360 2361	/* is this a valid port */2362 2363	if (co->index == -1 || co->index >= UART_NR)2364		co->index = 0;2365 2366	port = &s3c24xx_serial_ports[co->index].port;2367 2368	/* is the port configured? */2369 2370	if (port->mapbase == 0x0)2371		return -ENODEV;2372 2373	cons_uart = port;2374 2375	/*2376	 * Check whether an invalid uart number has been specified, and2377	 * if so, search for the first available port that does have2378	 * console support.2379	 */2380	if (options)2381		uart_parse_options(options, &baud, &parity, &bits, &flow);2382	else2383		s3c24xx_serial_get_options(port, &baud, &parity, &bits);2384 2385	dev_dbg(port->dev, "baud %d\n", baud);2386 2387	return uart_set_options(port, co, baud, parity, bits, flow);2388}2389 2390static struct console s3c24xx_serial_console = {2391	.name		= S3C24XX_SERIAL_NAME,2392	.device		= uart_console_device,2393	.flags		= CON_PRINTBUFFER,2394	.index		= -1,2395	.write		= s3c24xx_serial_console_write,2396	.setup		= s3c24xx_serial_console_setup,2397	.data		= &s3c24xx_uart_drv,2398};2399#endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */2400 2401#if defined(CONFIG_CPU_S3C6400) || defined(CONFIG_CPU_S3C6410)2402static const struct s3c24xx_serial_drv_data s3c6400_serial_drv_data = {2403	.info = {2404		.name		= "Samsung S3C6400 UART",2405		.type		= TYPE_S3C6400,2406		.port_type	= PORT_S3C6400,2407		.iotype		= UPIO_MEM,2408		.fifosize	= 64,2409		.has_divslot	= true,2410		.rx_fifomask	= S3C2440_UFSTAT_RXMASK,2411		.rx_fifoshift	= S3C2440_UFSTAT_RXSHIFT,2412		.rx_fifofull	= S3C2440_UFSTAT_RXFULL,2413		.tx_fifofull	= S3C2440_UFSTAT_TXFULL,2414		.tx_fifomask	= S3C2440_UFSTAT_TXMASK,2415		.tx_fifoshift	= S3C2440_UFSTAT_TXSHIFT,2416		.def_clk_sel	= S3C2410_UCON_CLKSEL2,2417		.num_clks	= 4,2418		.clksel_mask	= S3C6400_UCON_CLKMASK,2419		.clksel_shift	= S3C6400_UCON_CLKSHIFT,2420	},2421	.def_cfg = {2422		.ucon		= S3C2410_UCON_DEFAULT,2423		.ufcon		= S3C2410_UFCON_DEFAULT,2424	},2425};2426#define S3C6400_SERIAL_DRV_DATA (&s3c6400_serial_drv_data)2427#else2428#define S3C6400_SERIAL_DRV_DATA NULL2429#endif2430 2431#ifdef CONFIG_CPU_S5PV2102432static const struct s3c24xx_serial_drv_data s5pv210_serial_drv_data = {2433	.info = {2434		.name		= "Samsung S5PV210 UART",2435		.type		= TYPE_S3C6400,2436		.port_type	= PORT_S3C6400,2437		.iotype		= UPIO_MEM,2438		.has_divslot	= true,2439		.rx_fifomask	= S5PV210_UFSTAT_RXMASK,2440		.rx_fifoshift	= S5PV210_UFSTAT_RXSHIFT,2441		.rx_fifofull	= S5PV210_UFSTAT_RXFULL,2442		.tx_fifofull	= S5PV210_UFSTAT_TXFULL,2443		.tx_fifomask	= S5PV210_UFSTAT_TXMASK,2444		.tx_fifoshift	= S5PV210_UFSTAT_TXSHIFT,2445		.def_clk_sel	= S3C2410_UCON_CLKSEL0,2446		.num_clks	= 2,2447		.clksel_mask	= S5PV210_UCON_CLKMASK,2448		.clksel_shift	= S5PV210_UCON_CLKSHIFT,2449	},2450	.def_cfg = {2451		.ucon		= S5PV210_UCON_DEFAULT,2452		.ufcon		= S5PV210_UFCON_DEFAULT,2453	},2454	.fifosize = { 256, 64, 16, 16 },2455};2456#define S5PV210_SERIAL_DRV_DATA (&s5pv210_serial_drv_data)2457#else2458#define S5PV210_SERIAL_DRV_DATA	NULL2459#endif2460 2461#if defined(CONFIG_ARCH_EXYNOS)2462#define EXYNOS_COMMON_SERIAL_DRV_DATA				\2463	.info = {						\2464		.name		= "Samsung Exynos UART",	\2465		.type		= TYPE_S3C6400,			\2466		.port_type	= PORT_S3C6400,			\2467		.iotype		= UPIO_MEM,			\2468		.has_divslot	= true,				\2469		.rx_fifomask	= S5PV210_UFSTAT_RXMASK,	\2470		.rx_fifoshift	= S5PV210_UFSTAT_RXSHIFT,	\2471		.rx_fifofull	= S5PV210_UFSTAT_RXFULL,	\2472		.tx_fifofull	= S5PV210_UFSTAT_TXFULL,	\2473		.tx_fifomask	= S5PV210_UFSTAT_TXMASK,	\2474		.tx_fifoshift	= S5PV210_UFSTAT_TXSHIFT,	\2475		.def_clk_sel	= S3C2410_UCON_CLKSEL0,		\2476		.num_clks	= 1,				\2477		.clksel_mask	= 0,				\2478		.clksel_shift	= 0,				\2479	},							\2480	.def_cfg = {						\2481		.ucon		= S5PV210_UCON_DEFAULT,		\2482		.ufcon		= S5PV210_UFCON_DEFAULT,	\2483		.has_fracval	= 1,				\2484	}							\2485 2486static const struct s3c24xx_serial_drv_data exynos4210_serial_drv_data = {2487	EXYNOS_COMMON_SERIAL_DRV_DATA,2488	.fifosize = { 256, 64, 16, 16 },2489};2490 2491static const struct s3c24xx_serial_drv_data exynos5433_serial_drv_data = {2492	EXYNOS_COMMON_SERIAL_DRV_DATA,2493	.fifosize = { 64, 256, 16, 256 },2494};2495 2496static const struct s3c24xx_serial_drv_data exynos850_serial_drv_data = {2497	EXYNOS_COMMON_SERIAL_DRV_DATA,2498	.fifosize = { 256, 64, 64, 64 },2499};2500 2501static const struct s3c24xx_serial_drv_data gs101_serial_drv_data = {2502	.info = {2503		.name		= "Google GS101 UART",2504		.type		= TYPE_S3C6400,2505		.port_type	= PORT_S3C6400,2506		.iotype		= UPIO_MEM32,2507		.has_divslot	= true,2508		.rx_fifomask	= S5PV210_UFSTAT_RXMASK,2509		.rx_fifoshift	= S5PV210_UFSTAT_RXSHIFT,2510		.rx_fifofull	= S5PV210_UFSTAT_RXFULL,2511		.tx_fifofull	= S5PV210_UFSTAT_TXFULL,2512		.tx_fifomask	= S5PV210_UFSTAT_TXMASK,2513		.tx_fifoshift	= S5PV210_UFSTAT_TXSHIFT,2514		.def_clk_sel	= S3C2410_UCON_CLKSEL0,2515		.num_clks	= 1,2516		.clksel_mask	= 0,2517		.clksel_shift	= 0,2518	},2519	.def_cfg = {2520		.ucon		= S5PV210_UCON_DEFAULT,2521		.ufcon		= S5PV210_UFCON_DEFAULT,2522		.has_fracval	= 1,2523	},2524	/* samsung,uart-fifosize must be specified in the device tree. */2525	.fifosize = { 0 },2526};2527 2528#define EXYNOS4210_SERIAL_DRV_DATA (&exynos4210_serial_drv_data)2529#define EXYNOS5433_SERIAL_DRV_DATA (&exynos5433_serial_drv_data)2530#define EXYNOS850_SERIAL_DRV_DATA (&exynos850_serial_drv_data)2531#define GS101_SERIAL_DRV_DATA (&gs101_serial_drv_data)2532 2533#else2534#define EXYNOS4210_SERIAL_DRV_DATA NULL2535#define EXYNOS5433_SERIAL_DRV_DATA NULL2536#define EXYNOS850_SERIAL_DRV_DATA NULL2537#define GS101_SERIAL_DRV_DATA NULL2538#endif2539 2540#ifdef CONFIG_ARCH_APPLE2541static const struct s3c24xx_serial_drv_data s5l_serial_drv_data = {2542	.info = {2543		.name		= "Apple S5L UART",2544		.type		= TYPE_APPLE_S5L,2545		.port_type	= PORT_8250,2546		.iotype		= UPIO_MEM32,2547		.fifosize	= 16,2548		.rx_fifomask	= S3C2410_UFSTAT_RXMASK,2549		.rx_fifoshift	= S3C2410_UFSTAT_RXSHIFT,2550		.rx_fifofull	= S3C2410_UFSTAT_RXFULL,2551		.tx_fifofull	= S3C2410_UFSTAT_TXFULL,2552		.tx_fifomask	= S3C2410_UFSTAT_TXMASK,2553		.tx_fifoshift	= S3C2410_UFSTAT_TXSHIFT,2554		.def_clk_sel	= S3C2410_UCON_CLKSEL0,2555		.num_clks	= 1,2556		.clksel_mask	= 0,2557		.clksel_shift	= 0,2558		.ucon_mask	= APPLE_S5L_UCON_MASK,2559	},2560	.def_cfg = {2561		.ucon		= APPLE_S5L_UCON_DEFAULT,2562		.ufcon		= S3C2410_UFCON_DEFAULT,2563	},2564};2565#define S5L_SERIAL_DRV_DATA (&s5l_serial_drv_data)2566#else2567#define S5L_SERIAL_DRV_DATA NULL2568#endif2569 2570#if defined(CONFIG_ARCH_ARTPEC)2571static const struct s3c24xx_serial_drv_data artpec8_serial_drv_data = {2572	.info = {2573		.name		= "Axis ARTPEC-8 UART",2574		.type		= TYPE_S3C6400,2575		.port_type	= PORT_S3C6400,2576		.iotype		= UPIO_MEM,2577		.fifosize	= 64,2578		.has_divslot	= true,2579		.rx_fifomask	= S5PV210_UFSTAT_RXMASK,2580		.rx_fifoshift	= S5PV210_UFSTAT_RXSHIFT,2581		.rx_fifofull	= S5PV210_UFSTAT_RXFULL,2582		.tx_fifofull	= S5PV210_UFSTAT_TXFULL,2583		.tx_fifomask	= S5PV210_UFSTAT_TXMASK,2584		.tx_fifoshift	= S5PV210_UFSTAT_TXSHIFT,2585		.def_clk_sel	= S3C2410_UCON_CLKSEL0,2586		.num_clks	= 1,2587		.clksel_mask	= 0,2588		.clksel_shift	= 0,2589	},2590	.def_cfg = {2591		.ucon		= S5PV210_UCON_DEFAULT,2592		.ufcon		= S5PV210_UFCON_DEFAULT,2593		.has_fracval	= 1,2594	}2595};2596#define ARTPEC8_SERIAL_DRV_DATA (&artpec8_serial_drv_data)2597#else2598#define ARTPEC8_SERIAL_DRV_DATA (NULL)2599#endif2600 2601static const struct platform_device_id s3c24xx_serial_driver_ids[] = {2602	{2603		.name		= "s3c6400-uart",2604		.driver_data	= (kernel_ulong_t)S3C6400_SERIAL_DRV_DATA,2605	}, {2606		.name		= "s5pv210-uart",2607		.driver_data	= (kernel_ulong_t)S5PV210_SERIAL_DRV_DATA,2608	}, {2609		.name		= "exynos4210-uart",2610		.driver_data	= (kernel_ulong_t)EXYNOS4210_SERIAL_DRV_DATA,2611	}, {2612		.name		= "exynos5433-uart",2613		.driver_data	= (kernel_ulong_t)EXYNOS5433_SERIAL_DRV_DATA,2614	}, {2615		.name		= "s5l-uart",2616		.driver_data	= (kernel_ulong_t)S5L_SERIAL_DRV_DATA,2617	}, {2618		.name		= "exynos850-uart",2619		.driver_data	= (kernel_ulong_t)EXYNOS850_SERIAL_DRV_DATA,2620	}, {2621		.name		= "artpec8-uart",2622		.driver_data	= (kernel_ulong_t)ARTPEC8_SERIAL_DRV_DATA,2623	}, {2624		.name		= "gs101-uart",2625		.driver_data	= (kernel_ulong_t)GS101_SERIAL_DRV_DATA,2626	},2627	{ },2628};2629MODULE_DEVICE_TABLE(platform, s3c24xx_serial_driver_ids);2630 2631#ifdef CONFIG_OF2632static const struct of_device_id s3c24xx_uart_dt_match[] = {2633	{ .compatible = "samsung,s3c6400-uart",2634		.data = S3C6400_SERIAL_DRV_DATA },2635	{ .compatible = "samsung,s5pv210-uart",2636		.data = S5PV210_SERIAL_DRV_DATA },2637	{ .compatible = "samsung,exynos4210-uart",2638		.data = EXYNOS4210_SERIAL_DRV_DATA },2639	{ .compatible = "samsung,exynos5433-uart",2640		.data = EXYNOS5433_SERIAL_DRV_DATA },2641	{ .compatible = "apple,s5l-uart",2642		.data = S5L_SERIAL_DRV_DATA },2643	{ .compatible = "samsung,exynos850-uart",2644		.data = EXYNOS850_SERIAL_DRV_DATA },2645	{ .compatible = "axis,artpec8-uart",2646		.data = ARTPEC8_SERIAL_DRV_DATA },2647	{ .compatible = "google,gs101-uart",2648		.data = GS101_SERIAL_DRV_DATA },2649	{},2650};2651MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match);2652#endif2653 2654static struct platform_driver samsung_serial_driver = {2655	.probe		= s3c24xx_serial_probe,2656	.remove_new	= s3c24xx_serial_remove,2657	.id_table	= s3c24xx_serial_driver_ids,2658	.driver		= {2659		.name	= "samsung-uart",2660		.pm	= SERIAL_SAMSUNG_PM_OPS,2661		.of_match_table	= of_match_ptr(s3c24xx_uart_dt_match),2662	},2663};2664 2665static int __init samsung_serial_init(void)2666{2667	int ret;2668 2669	s3c24xx_serial_register_console();2670 2671	ret = platform_driver_register(&samsung_serial_driver);2672	if (ret) {2673		s3c24xx_serial_unregister_console();2674		return ret;2675	}2676 2677	return 0;2678}2679 2680static void __exit samsung_serial_exit(void)2681{2682	platform_driver_unregister(&samsung_serial_driver);2683	s3c24xx_serial_unregister_console();2684}2685 2686module_init(samsung_serial_init);2687module_exit(samsung_serial_exit);2688 2689#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE2690/*2691 * Early console.2692 */2693 2694static void wr_reg_barrier(const struct uart_port *port, u32 reg, u32 val)2695{2696	switch (port->iotype) {2697	case UPIO_MEM:2698		writeb(val, portaddr(port, reg));2699		break;2700	case UPIO_MEM32:2701		writel(val, portaddr(port, reg));2702		break;2703	}2704}2705 2706struct samsung_early_console_data {2707	u32 txfull_mask;2708	u32 rxfifo_mask;2709};2710 2711static void samsung_early_busyuart(const struct uart_port *port)2712{2713	while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE))2714		;2715}2716 2717static void samsung_early_busyuart_fifo(const struct uart_port *port)2718{2719	const struct samsung_early_console_data *data = port->private_data;2720 2721	while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask)2722		;2723}2724 2725static void samsung_early_putc(struct uart_port *port, unsigned char c)2726{2727	if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)2728		samsung_early_busyuart_fifo(port);2729	else2730		samsung_early_busyuart(port);2731 2732	wr_reg_barrier(port, S3C2410_UTXH, c);2733}2734 2735static void samsung_early_write(struct console *con, const char *s,2736				unsigned int n)2737{2738	struct earlycon_device *dev = con->data;2739 2740	uart_console_write(&dev->port, s, n, samsung_early_putc);2741}2742 2743static int samsung_early_read(struct console *con, char *s, unsigned int n)2744{2745	struct earlycon_device *dev = con->data;2746	const struct samsung_early_console_data *data = dev->port.private_data;2747	int num_read = 0;2748	u32 ch, ufstat;2749 2750	while (num_read < n) {2751		ufstat = rd_regl(&dev->port, S3C2410_UFSTAT);2752		if (!(ufstat & data->rxfifo_mask))2753			break;2754		ch = rd_reg(&dev->port, S3C2410_URXH);2755		if (ch == NO_POLL_CHAR)2756			break;2757 2758		s[num_read++] = ch;2759	}2760 2761	return num_read;2762}2763 2764static int __init samsung_early_console_setup(struct earlycon_device *device,2765					      const char *opt)2766{2767	if (!device->port.membase)2768		return -ENODEV;2769 2770	device->con->write = samsung_early_write;2771	device->con->read = samsung_early_read;2772	return 0;2773}2774 2775/* S3C2410 */2776static struct samsung_early_console_data s3c2410_early_console_data = {2777	.txfull_mask = S3C2410_UFSTAT_TXFULL,2778	.rxfifo_mask = S3C2410_UFSTAT_RXFULL | S3C2410_UFSTAT_RXMASK,2779};2780 2781/* S3C64xx */2782static struct samsung_early_console_data s3c2440_early_console_data = {2783	.txfull_mask = S3C2440_UFSTAT_TXFULL,2784	.rxfifo_mask = S3C2440_UFSTAT_RXFULL | S3C2440_UFSTAT_RXMASK,2785};2786 2787static int __init s3c2440_early_console_setup(struct earlycon_device *device,2788					      const char *opt)2789{2790	device->port.private_data = &s3c2440_early_console_data;2791	return samsung_early_console_setup(device, opt);2792}2793 2794OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart",2795			s3c2440_early_console_setup);2796 2797/* S5PV210, Exynos */2798static struct samsung_early_console_data s5pv210_early_console_data = {2799	.txfull_mask = S5PV210_UFSTAT_TXFULL,2800	.rxfifo_mask = S5PV210_UFSTAT_RXFULL | S5PV210_UFSTAT_RXMASK,2801};2802 2803static int __init s5pv210_early_console_setup(struct earlycon_device *device,2804					      const char *opt)2805{2806	device->port.private_data = &s5pv210_early_console_data;2807	return samsung_early_console_setup(device, opt);2808}2809 2810OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart",2811			s5pv210_early_console_setup);2812OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",2813			s5pv210_early_console_setup);2814OF_EARLYCON_DECLARE(artpec8, "axis,artpec8-uart",2815			s5pv210_early_console_setup);2816 2817static int __init gs101_early_console_setup(struct earlycon_device *device,2818					    const char *opt)2819{2820	/* gs101 always expects MMIO32 register accesses. */2821	device->port.iotype = UPIO_MEM32;2822 2823	return s5pv210_early_console_setup(device, opt);2824}2825 2826OF_EARLYCON_DECLARE(gs101, "google,gs101-uart", gs101_early_console_setup);2827 2828/* Apple S5L */2829static int __init apple_s5l_early_console_setup(struct earlycon_device *device,2830						const char *opt)2831{2832	/* Apple A7-A11 requires MMIO32 register accesses. */2833	device->port.iotype = UPIO_MEM32;2834 2835	/* Close enough to S3C2410 for earlycon... */2836	device->port.private_data = &s3c2410_early_console_data;2837 2838#ifdef CONFIG_ARM642839	/* ... but we need to override the existing fixmap entry as nGnRnE */2840	__set_fixmap(FIX_EARLYCON_MEM_BASE, device->port.mapbase,2841		     __pgprot(PROT_DEVICE_nGnRnE));2842#endif2843	return samsung_early_console_setup(device, opt);2844}2845 2846OF_EARLYCON_DECLARE(s5l, "apple,s5l-uart", apple_s5l_early_console_setup);2847#endif2848 2849MODULE_ALIAS("platform:samsung-uart");2850MODULE_DESCRIPTION("Samsung SoC Serial port driver");2851MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");2852MODULE_LICENSE("GPL v2");2853