brintos

brintos / linux-shallow public Read only

0
0
Text · 19.4 KiB · cde5f1c Raw
840 lines · c
1// SPDX-License-Identifier: GPL-2.0+2/*3 *  Copyright (C) 2008 Christian Pellegrin <chripell@evolware.org>4 *5 * Notes: the MAX3100 doesn't provide an interrupt on CTS so we have6 * to use polling for flow control. TX empty IRQ is unusable, since7 * writing conf clears FIFO buffer and we cannot have this interrupt8 * always asking us for attention.9 *10 * The initial minor number is 209 in the low-density serial port:11 * mknod /dev/ttyMAX0 c 204 20912 */13 14#define MAX3100_MAJOR 20415#define MAX3100_MINOR 20916/* 4 MAX3100s should be enough for everyone */17#define MAX_MAX3100 418 19#include <linux/container_of.h>20#include <linux/delay.h>21#include <linux/device.h>22#include <linux/freezer.h>23#include <linux/mod_devicetable.h>24#include <linux/module.h>25#include <linux/pm.h>26#include <linux/property.h>27#include <linux/serial_core.h>28#include <linux/serial.h>29#include <linux/slab.h>30#include <linux/spi/spi.h>31#include <linux/tty_flip.h>32#include <linux/tty.h>33#include <linux/types.h>34 35#include <linux/unaligned.h>36 37#define MAX3100_C    (1<<14)38#define MAX3100_D    (0<<14)39#define MAX3100_W    (1<<15)40#define MAX3100_RX   (0<<15)41 42#define MAX3100_WC   (MAX3100_W  | MAX3100_C)43#define MAX3100_RC   (MAX3100_RX | MAX3100_C)44#define MAX3100_WD   (MAX3100_W  | MAX3100_D)45#define MAX3100_RD   (MAX3100_RX | MAX3100_D)46#define MAX3100_CMD  (3 << 14)47 48#define MAX3100_T    (1<<14)49#define MAX3100_R    (1<<15)50 51#define MAX3100_FEN  (1<<13)52#define MAX3100_SHDN (1<<12)53#define MAX3100_TM   (1<<11)54#define MAX3100_RM   (1<<10)55#define MAX3100_PM   (1<<9)56#define MAX3100_RAM  (1<<8)57#define MAX3100_IR   (1<<7)58#define MAX3100_ST   (1<<6)59#define MAX3100_PE   (1<<5)60#define MAX3100_L    (1<<4)61#define MAX3100_BAUD (0xf)62 63#define MAX3100_TE   (1<<10)64#define MAX3100_RAFE (1<<10)65#define MAX3100_RTS  (1<<9)66#define MAX3100_CTS  (1<<9)67#define MAX3100_PT   (1<<8)68#define MAX3100_DATA (0xff)69 70#define MAX3100_RT   (MAX3100_R | MAX3100_T)71#define MAX3100_RTC  (MAX3100_RT | MAX3100_CTS | MAX3100_RAFE)72 73/* the following simulate a status reg for ignore_status_mask */74#define MAX3100_STATUS_PE 175#define MAX3100_STATUS_FE 276#define MAX3100_STATUS_OE 477 78struct max3100_port {79	struct uart_port port;80	struct spi_device *spi;81 82	int cts;	        /* last CTS received for flow ctrl */83	int tx_empty;		/* last TX empty bit */84 85	spinlock_t conf_lock;	/* shared data */86	int conf_commit;	/* need to make changes */87	int conf;		/* configuration for the MAX3100088				 * (bits 0-7, bits 8-11 are irqs) */89	int rts_commit;	        /* need to change rts */90	int rts;		/* rts status */91	int baud;		/* current baud rate */92 93	int parity;		/* keeps track if we should send parity */94#define MAX3100_PARITY_ON 195#define MAX3100_PARITY_ODD 296#define MAX3100_7BIT 497	int rx_enabled;	        /* if we should rx chars */98 99	int minor;		/* minor number */100	int loopback_commit;	/* need to change loopback */101	int loopback;		/* 1 if we are in loopback mode */102 103	/* for handling irqs: need workqueue since we do spi_sync */104	struct workqueue_struct *workqueue;105	struct work_struct work;106	/* set to 1 to make the workhandler exit as soon as possible */107	int  force_end_work;108	/* need to know we are suspending to avoid deadlock on workqueue */109	int suspending;110 111	struct timer_list	timer;112};113 114static inline struct max3100_port *to_max3100_port(struct uart_port *port)115{116	return container_of(port, struct max3100_port, port);117}118 119static struct max3100_port *max3100s[MAX_MAX3100]; /* the chips */120static DEFINE_MUTEX(max3100s_lock);		   /* race on probe */121 122static int max3100_do_parity(struct max3100_port *s, u16 c)123{124	int parity;125 126	if (s->parity & MAX3100_PARITY_ODD)127		parity = 1;128	else129		parity = 0;130 131	if (s->parity & MAX3100_7BIT)132		c &= 0x7f;133	else134		c &= 0xff;135 136	parity = parity ^ (hweight8(c) & 1);137	return parity;138}139 140static int max3100_check_parity(struct max3100_port *s, u16 c)141{142	return max3100_do_parity(s, c) == ((c >> 8) & 1);143}144 145static void max3100_calc_parity(struct max3100_port *s, u16 *c)146{147	if (s->parity & MAX3100_7BIT)148		*c &= 0x7f;149	else150		*c &= 0xff;151 152	if (s->parity & MAX3100_PARITY_ON)153		*c |= max3100_do_parity(s, *c) << 8;154}155 156static int max3100_sr(struct max3100_port *s, u16 tx, u16 *rx)157{158	struct spi_message message;159	__be16 etx, erx;160	int status;161	struct spi_transfer tran = {162		.tx_buf = &etx,163		.rx_buf = &erx,164		.len = 2,165	};166 167	etx = cpu_to_be16(tx);168	spi_message_init(&message);169	spi_message_add_tail(&tran, &message);170	status = spi_sync(s->spi, &message);171	if (status) {172		dev_warn(&s->spi->dev, "error while calling spi_sync\n");173		return -EIO;174	}175	*rx = be16_to_cpu(erx);176	s->tx_empty = (*rx & MAX3100_T) > 0;177	dev_dbg(&s->spi->dev, "%04x - %04x\n", tx, *rx);178	return 0;179}180 181static int max3100_handlerx_unlocked(struct max3100_port *s, u16 rx)182{183	unsigned int status = 0;184	int ret = 0, cts;185	u8 ch, flg;186 187	if (rx & MAX3100_R && s->rx_enabled) {188		dev_dbg(&s->spi->dev, "%s\n", __func__);189		ch = rx & (s->parity & MAX3100_7BIT ? 0x7f : 0xff);190		if (rx & MAX3100_RAFE) {191			s->port.icount.frame++;192			flg = TTY_FRAME;193			status |= MAX3100_STATUS_FE;194		} else {195			if (s->parity & MAX3100_PARITY_ON) {196				if (max3100_check_parity(s, rx)) {197					s->port.icount.rx++;198					flg = TTY_NORMAL;199				} else {200					s->port.icount.parity++;201					flg = TTY_PARITY;202					status |= MAX3100_STATUS_PE;203				}204			} else {205				s->port.icount.rx++;206				flg = TTY_NORMAL;207			}208		}209		uart_insert_char(&s->port, status, MAX3100_STATUS_OE, ch, flg);210		ret = 1;211	}212 213	cts = (rx & MAX3100_CTS) > 0;214	if (s->cts != cts) {215		s->cts = cts;216		uart_handle_cts_change(&s->port, cts);217	}218 219	return ret;220}221 222static int max3100_handlerx(struct max3100_port *s, u16 rx)223{224	unsigned long flags;225	int ret;226 227	uart_port_lock_irqsave(&s->port, &flags);228	ret = max3100_handlerx_unlocked(s, rx);229	uart_port_unlock_irqrestore(&s->port, flags);230	return ret;231}232 233static void max3100_work(struct work_struct *w)234{235	struct max3100_port *s = container_of(w, struct max3100_port, work);236	struct tty_port *tport = &s->port.state->port;237	unsigned char ch;238	int conf, cconf, cloopback, crts;239	int rxchars;240	u16 tx, rx;241 242	dev_dbg(&s->spi->dev, "%s\n", __func__);243 244	rxchars = 0;245	do {246		spin_lock(&s->conf_lock);247		conf = s->conf;248		cconf = s->conf_commit;249		s->conf_commit = 0;250		cloopback = s->loopback_commit;251		s->loopback_commit = 0;252		crts = s->rts_commit;253		s->rts_commit = 0;254		spin_unlock(&s->conf_lock);255		if (cconf)256			max3100_sr(s, MAX3100_WC | conf, &rx);257		if (cloopback)258			max3100_sr(s, 0x4001, &rx);259		if (crts) {260			max3100_sr(s, MAX3100_WD | MAX3100_TE |261				   (s->rts ? MAX3100_RTS : 0), &rx);262			rxchars += max3100_handlerx(s, rx);263		}264 265		max3100_sr(s, MAX3100_RD, &rx);266		rxchars += max3100_handlerx(s, rx);267 268		if (rx & MAX3100_T) {269			tx = 0xffff;270			if (s->port.x_char) {271				tx = s->port.x_char;272				s->port.icount.tx++;273				s->port.x_char = 0;274			} else if (!uart_tx_stopped(&s->port) &&275					uart_fifo_get(&s->port, &ch)) {276				tx = ch;277			}278			if (tx != 0xffff) {279				max3100_calc_parity(s, &tx);280				tx |= MAX3100_WD | (s->rts ? MAX3100_RTS : 0);281				max3100_sr(s, tx, &rx);282				rxchars += max3100_handlerx(s, rx);283			}284		}285 286		if (rxchars > 16) {287			tty_flip_buffer_push(&s->port.state->port);288			rxchars = 0;289		}290		if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)291			uart_write_wakeup(&s->port);292 293	} while (!s->force_end_work &&294		 !freezing(current) &&295		 ((rx & MAX3100_R) ||296		  (!kfifo_is_empty(&tport->xmit_fifo) &&297		   !uart_tx_stopped(&s->port))));298 299	if (rxchars > 0)300		tty_flip_buffer_push(&s->port.state->port);301}302 303static void max3100_dowork(struct max3100_port *s)304{305	if (!s->force_end_work && !freezing(current) && !s->suspending)306		queue_work(s->workqueue, &s->work);307}308 309static void max3100_timeout(struct timer_list *t)310{311	struct max3100_port *s = from_timer(s, t, timer);312 313	max3100_dowork(s);314	mod_timer(&s->timer, jiffies + uart_poll_timeout(&s->port));315}316 317static irqreturn_t max3100_irq(int irqno, void *dev_id)318{319	struct max3100_port *s = dev_id;320 321	dev_dbg(&s->spi->dev, "%s\n", __func__);322 323	max3100_dowork(s);324	return IRQ_HANDLED;325}326 327static void max3100_enable_ms(struct uart_port *port)328{329	struct max3100_port *s = to_max3100_port(port);330 331	mod_timer(&s->timer, jiffies);332	dev_dbg(&s->spi->dev, "%s\n", __func__);333}334 335static void max3100_start_tx(struct uart_port *port)336{337	struct max3100_port *s = to_max3100_port(port);338 339	dev_dbg(&s->spi->dev, "%s\n", __func__);340 341	max3100_dowork(s);342}343 344static void max3100_stop_rx(struct uart_port *port)345{346	struct max3100_port *s = to_max3100_port(port);347 348	dev_dbg(&s->spi->dev, "%s\n", __func__);349 350	s->rx_enabled = 0;351	spin_lock(&s->conf_lock);352	s->conf &= ~MAX3100_RM;353	s->conf_commit = 1;354	spin_unlock(&s->conf_lock);355	max3100_dowork(s);356}357 358static unsigned int max3100_tx_empty(struct uart_port *port)359{360	struct max3100_port *s = to_max3100_port(port);361 362	dev_dbg(&s->spi->dev, "%s\n", __func__);363 364	/* may not be truly up-to-date */365	max3100_dowork(s);366	return s->tx_empty;367}368 369static unsigned int max3100_get_mctrl(struct uart_port *port)370{371	struct max3100_port *s = to_max3100_port(port);372 373	dev_dbg(&s->spi->dev, "%s\n", __func__);374 375	/* may not be truly up-to-date */376	max3100_dowork(s);377	/* always assert DCD and DSR since these lines are not wired */378	return (s->cts ? TIOCM_CTS : 0) | TIOCM_DSR | TIOCM_CAR;379}380 381static void max3100_set_mctrl(struct uart_port *port, unsigned int mctrl)382{383	struct max3100_port *s = to_max3100_port(port);384	int loopback, rts;385 386	dev_dbg(&s->spi->dev, "%s\n", __func__);387 388	loopback = (mctrl & TIOCM_LOOP) > 0;389	rts = (mctrl & TIOCM_RTS) > 0;390 391	spin_lock(&s->conf_lock);392	if (s->loopback != loopback) {393		s->loopback = loopback;394		s->loopback_commit = 1;395	}396	if (s->rts != rts) {397		s->rts = rts;398		s->rts_commit = 1;399	}400	if (s->loopback_commit || s->rts_commit)401		max3100_dowork(s);402	spin_unlock(&s->conf_lock);403}404 405static void406max3100_set_termios(struct uart_port *port, struct ktermios *termios,407		    const struct ktermios *old)408{409	struct max3100_port *s = to_max3100_port(port);410	unsigned int baud = port->uartclk / 16;411	unsigned int baud230400 = (baud == 230400) ? 1 : 0;412	unsigned cflag;413	u32 param_new, param_mask, parity = 0;414 415	dev_dbg(&s->spi->dev, "%s\n", __func__);416 417	cflag = termios->c_cflag;418	param_mask = 0;419 420	baud = tty_termios_baud_rate(termios);421	param_new = s->conf & MAX3100_BAUD;422	switch (baud) {423	case 300:424		if (baud230400)425			baud = s->baud;426		else427			param_new = 15;428		break;429	case 600:430		param_new = 14 + baud230400;431		break;432	case 1200:433		param_new = 13 + baud230400;434		break;435	case 2400:436		param_new = 12 + baud230400;437		break;438	case 4800:439		param_new = 11 + baud230400;440		break;441	case 9600:442		param_new = 10 + baud230400;443		break;444	case 19200:445		param_new = 9 + baud230400;446		break;447	case 38400:448		param_new = 8 + baud230400;449		break;450	case 57600:451		param_new = 1 + baud230400;452		break;453	case 115200:454		param_new = 0 + baud230400;455		break;456	case 230400:457		if (baud230400)458			param_new = 0;459		else460			baud = s->baud;461		break;462	default:463		baud = s->baud;464	}465	tty_termios_encode_baud_rate(termios, baud, baud);466	s->baud = baud;467	param_mask |= MAX3100_BAUD;468 469	if ((cflag & CSIZE) == CS8) {470		param_new &= ~MAX3100_L;471		parity &= ~MAX3100_7BIT;472	} else {473		param_new |= MAX3100_L;474		parity |= MAX3100_7BIT;475		cflag = (cflag & ~CSIZE) | CS7;476	}477	param_mask |= MAX3100_L;478 479	if (cflag & CSTOPB)480		param_new |= MAX3100_ST;481	else482		param_new &= ~MAX3100_ST;483	param_mask |= MAX3100_ST;484 485	if (cflag & PARENB) {486		param_new |= MAX3100_PE;487		parity |= MAX3100_PARITY_ON;488	} else {489		param_new &= ~MAX3100_PE;490		parity &= ~MAX3100_PARITY_ON;491	}492	param_mask |= MAX3100_PE;493 494	if (cflag & PARODD)495		parity |= MAX3100_PARITY_ODD;496	else497		parity &= ~MAX3100_PARITY_ODD;498 499	/* mask termios capabilities we don't support */500	cflag &= ~CMSPAR;501	termios->c_cflag = cflag;502 503	s->port.ignore_status_mask = 0;504	if (termios->c_iflag & IGNPAR)505		s->port.ignore_status_mask |=506			MAX3100_STATUS_PE | MAX3100_STATUS_FE |507			MAX3100_STATUS_OE;508 509	del_timer_sync(&s->timer);510	uart_update_timeout(port, termios->c_cflag, baud);511 512	spin_lock(&s->conf_lock);513	s->conf = (s->conf & ~param_mask) | (param_new & param_mask);514	s->conf_commit = 1;515	s->parity = parity;516	spin_unlock(&s->conf_lock);517	max3100_dowork(s);518 519	if (UART_ENABLE_MS(&s->port, termios->c_cflag))520		max3100_enable_ms(&s->port);521}522 523static void max3100_shutdown(struct uart_port *port)524{525	struct max3100_port *s = to_max3100_port(port);526	u16 rx;527 528	dev_dbg(&s->spi->dev, "%s\n", __func__);529 530	if (s->suspending)531		return;532 533	s->force_end_work = 1;534 535	del_timer_sync(&s->timer);536 537	if (s->workqueue) {538		destroy_workqueue(s->workqueue);539		s->workqueue = NULL;540	}541	if (port->irq)542		free_irq(port->irq, s);543 544	/* set shutdown mode to save power */545	max3100_sr(s, MAX3100_WC | MAX3100_SHDN, &rx);546}547 548static int max3100_startup(struct uart_port *port)549{550	struct max3100_port *s = to_max3100_port(port);551	char b[12];552	int ret;553 554	dev_dbg(&s->spi->dev, "%s\n", __func__);555 556	s->conf = MAX3100_RM;557	s->baud = port->uartclk / 16;558	s->rx_enabled = 1;559 560	if (s->suspending)561		return 0;562 563	s->force_end_work = 0;564	s->parity = 0;565	s->rts = 0;566 567	sprintf(b, "max3100-%d", s->minor);568	s->workqueue = create_freezable_workqueue(b);569	if (!s->workqueue) {570		dev_warn(&s->spi->dev, "cannot create workqueue\n");571		return -EBUSY;572	}573	INIT_WORK(&s->work, max3100_work);574 575	ret = request_irq(port->irq, max3100_irq, IRQF_TRIGGER_FALLING, "max3100", s);576	if (ret < 0) {577		dev_warn(&s->spi->dev, "cannot allocate irq %d\n", port->irq);578		port->irq = 0;579		destroy_workqueue(s->workqueue);580		s->workqueue = NULL;581		return -EBUSY;582	}583 584	s->conf_commit = 1;585	max3100_dowork(s);586	/* wait for clock to settle */587	msleep(50);588 589	max3100_enable_ms(&s->port);590 591	return 0;592}593 594static const char *max3100_type(struct uart_port *port)595{596	struct max3100_port *s = to_max3100_port(port);597 598	dev_dbg(&s->spi->dev, "%s\n", __func__);599 600	return s->port.type == PORT_MAX3100 ? "MAX3100" : NULL;601}602 603static void max3100_release_port(struct uart_port *port)604{605	struct max3100_port *s = to_max3100_port(port);606 607	dev_dbg(&s->spi->dev, "%s\n", __func__);608}609 610static void max3100_config_port(struct uart_port *port, int flags)611{612	struct max3100_port *s = to_max3100_port(port);613 614	dev_dbg(&s->spi->dev, "%s\n", __func__);615 616	if (flags & UART_CONFIG_TYPE)617		s->port.type = PORT_MAX3100;618}619 620static int max3100_verify_port(struct uart_port *port,621			       struct serial_struct *ser)622{623	struct max3100_port *s = to_max3100_port(port);624	int ret = -EINVAL;625 626	dev_dbg(&s->spi->dev, "%s\n", __func__);627 628	if (ser->type == PORT_UNKNOWN || ser->type == PORT_MAX3100)629		ret = 0;630	return ret;631}632 633static void max3100_stop_tx(struct uart_port *port)634{635	struct max3100_port *s = to_max3100_port(port);636 637	dev_dbg(&s->spi->dev, "%s\n", __func__);638}639 640static int max3100_request_port(struct uart_port *port)641{642	struct max3100_port *s = to_max3100_port(port);643 644	dev_dbg(&s->spi->dev, "%s\n", __func__);645	return 0;646}647 648static void max3100_break_ctl(struct uart_port *port, int break_state)649{650	struct max3100_port *s = to_max3100_port(port);651 652	dev_dbg(&s->spi->dev, "%s\n", __func__);653}654 655static const struct uart_ops max3100_ops = {656	.tx_empty	= max3100_tx_empty,657	.set_mctrl	= max3100_set_mctrl,658	.get_mctrl	= max3100_get_mctrl,659	.stop_tx        = max3100_stop_tx,660	.start_tx	= max3100_start_tx,661	.stop_rx	= max3100_stop_rx,662	.enable_ms      = max3100_enable_ms,663	.break_ctl      = max3100_break_ctl,664	.startup	= max3100_startup,665	.shutdown	= max3100_shutdown,666	.set_termios	= max3100_set_termios,667	.type		= max3100_type,668	.release_port   = max3100_release_port,669	.request_port   = max3100_request_port,670	.config_port	= max3100_config_port,671	.verify_port	= max3100_verify_port,672};673 674static struct uart_driver max3100_uart_driver = {675	.owner          = THIS_MODULE,676	.driver_name    = "ttyMAX",677	.dev_name       = "ttyMAX",678	.major          = MAX3100_MAJOR,679	.minor          = MAX3100_MINOR,680	.nr             = MAX_MAX3100,681};682static int uart_driver_registered;683 684static int max3100_probe(struct spi_device *spi)685{686	struct device *dev = &spi->dev;687	int i, retval;688	u16 rx;689 690	mutex_lock(&max3100s_lock);691 692	if (!uart_driver_registered) {693		retval = uart_register_driver(&max3100_uart_driver);694		if (retval) {695			mutex_unlock(&max3100s_lock);696			return dev_err_probe(dev, retval, "Couldn't register max3100 uart driver\n");697		}698 699		uart_driver_registered = 1;700	}701 702	for (i = 0; i < MAX_MAX3100; i++)703		if (!max3100s[i])704			break;705	if (i == MAX_MAX3100) {706		mutex_unlock(&max3100s_lock);707		return dev_err_probe(dev, -ENOMEM, "too many MAX3100 chips\n");708	}709 710	max3100s[i] = kzalloc(sizeof(struct max3100_port), GFP_KERNEL);711	if (!max3100s[i]) {712		mutex_unlock(&max3100s_lock);713		return -ENOMEM;714	}715	max3100s[i]->spi = spi;716	spin_lock_init(&max3100s[i]->conf_lock);717	spi_set_drvdata(spi, max3100s[i]);718	max3100s[i]->minor = i;719	timer_setup(&max3100s[i]->timer, max3100_timeout, 0);720 721	dev_dbg(&spi->dev, "%s: adding port %d\n", __func__, i);722	max3100s[i]->port.irq = spi->irq;723	max3100s[i]->port.fifosize = 16;724	max3100s[i]->port.ops = &max3100_ops;725	max3100s[i]->port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;726	max3100s[i]->port.line = i;727	max3100s[i]->port.type = PORT_MAX3100;728	max3100s[i]->port.dev = &spi->dev;729 730	/* Read clock frequency from a property, uart_add_one_port() will fail if it's not set */731	device_property_read_u32(dev, "clock-frequency", &max3100s[i]->port.uartclk);732 733	retval = uart_add_one_port(&max3100_uart_driver, &max3100s[i]->port);734	if (retval < 0)735		dev_err_probe(dev, retval, "uart_add_one_port failed for line %d\n", i);736 737	/* set shutdown mode to save power. Will be woken-up on open */738	max3100_sr(max3100s[i], MAX3100_WC | MAX3100_SHDN, &rx);739	mutex_unlock(&max3100s_lock);740	return 0;741}742 743static void max3100_remove(struct spi_device *spi)744{745	struct max3100_port *s = spi_get_drvdata(spi);746	int i;747 748	mutex_lock(&max3100s_lock);749 750	/* find out the index for the chip we are removing */751	for (i = 0; i < MAX_MAX3100; i++)752		if (max3100s[i] == s) {753			dev_dbg(&spi->dev, "%s: removing port %d\n", __func__, i);754			uart_remove_one_port(&max3100_uart_driver, &max3100s[i]->port);755			kfree(max3100s[i]);756			max3100s[i] = NULL;757			break;758		}759 760	WARN_ON(i == MAX_MAX3100);761	762	/* check if this is the last chip we have */763	for (i = 0; i < MAX_MAX3100; i++)764		if (max3100s[i]) {765			mutex_unlock(&max3100s_lock);766			return;767		}768	pr_debug("removing max3100 driver\n");769	uart_unregister_driver(&max3100_uart_driver);770	uart_driver_registered = 0;771 772	mutex_unlock(&max3100s_lock);773}774 775static int max3100_suspend(struct device *dev)776{777	struct max3100_port *s = dev_get_drvdata(dev);778	u16 rx;779 780	dev_dbg(&s->spi->dev, "%s\n", __func__);781 782	disable_irq(s->port.irq);783 784	s->suspending = 1;785	uart_suspend_port(&max3100_uart_driver, &s->port);786 787	/* no HW suspend, so do SW one */788	max3100_sr(s, MAX3100_WC | MAX3100_SHDN, &rx);789	return 0;790}791 792static int max3100_resume(struct device *dev)793{794	struct max3100_port *s = dev_get_drvdata(dev);795 796	dev_dbg(&s->spi->dev, "%s\n", __func__);797 798	uart_resume_port(&max3100_uart_driver, &s->port);799	s->suspending = 0;800 801	enable_irq(s->port.irq);802 803	s->conf_commit = 1;804	if (s->workqueue)805		max3100_dowork(s);806 807	return 0;808}809 810static DEFINE_SIMPLE_DEV_PM_OPS(max3100_pm_ops, max3100_suspend, max3100_resume);811 812static const struct spi_device_id max3100_spi_id[] = {813	{ "max3100" },814	{ }815};816MODULE_DEVICE_TABLE(spi, max3100_spi_id);817 818static const struct of_device_id max3100_of_match[] = {819	{ .compatible = "maxim,max3100" },820	{ }821};822MODULE_DEVICE_TABLE(of, max3100_of_match);823 824static struct spi_driver max3100_driver = {825	.driver = {826		.name		= "max3100",827		.of_match_table	= max3100_of_match,828		.pm		= pm_sleep_ptr(&max3100_pm_ops),829	},830	.probe		= max3100_probe,831	.remove		= max3100_remove,832	.id_table	= max3100_spi_id,833};834 835module_spi_driver(max3100_driver);836 837MODULE_DESCRIPTION("MAX3100 driver");838MODULE_AUTHOR("Christian Pellegrin <chripell@evolware.org>");839MODULE_LICENSE("GPL");840