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1// SPDX-License-Identifier: GPL-2.0-only2// Copyright (C) 2014 Broadcom Corporation3 4#include <linux/delay.h>5#include <linux/i2c.h>6#include <linux/interrupt.h>7#include <linux/io.h>8#include <linux/kernel.h>9#include <linux/module.h>10#include <linux/of.h>11#include <linux/platform_device.h>12#include <linux/slab.h>13 14#define IDM_CTRL_DIRECT_OFFSET       0x0015#define CFG_OFFSET                   0x0016#define CFG_RESET_SHIFT              3117#define CFG_EN_SHIFT                 3018#define CFG_SLAVE_ADDR_0_SHIFT       2819#define CFG_M_RETRY_CNT_SHIFT        1620#define CFG_M_RETRY_CNT_MASK         0x0f21 22#define TIM_CFG_OFFSET               0x0423#define TIM_CFG_MODE_400_SHIFT       3124#define TIM_RAND_SLAVE_STRETCH_SHIFT      2425#define TIM_RAND_SLAVE_STRETCH_MASK       0x7f26#define TIM_PERIODIC_SLAVE_STRETCH_SHIFT  1627#define TIM_PERIODIC_SLAVE_STRETCH_MASK   0x7f28 29#define S_CFG_SMBUS_ADDR_OFFSET           0x0830#define S_CFG_EN_NIC_SMB_ADDR3_SHIFT      3131#define S_CFG_NIC_SMB_ADDR3_SHIFT         2432#define S_CFG_NIC_SMB_ADDR3_MASK          0x7f33#define S_CFG_EN_NIC_SMB_ADDR2_SHIFT      2334#define S_CFG_NIC_SMB_ADDR2_SHIFT         1635#define S_CFG_NIC_SMB_ADDR2_MASK          0x7f36#define S_CFG_EN_NIC_SMB_ADDR1_SHIFT      1537#define S_CFG_NIC_SMB_ADDR1_SHIFT         838#define S_CFG_NIC_SMB_ADDR1_MASK          0x7f39#define S_CFG_EN_NIC_SMB_ADDR0_SHIFT      740#define S_CFG_NIC_SMB_ADDR0_SHIFT         041#define S_CFG_NIC_SMB_ADDR0_MASK          0x7f42 43#define M_FIFO_CTRL_OFFSET           0x0c44#define M_FIFO_RX_FLUSH_SHIFT        3145#define M_FIFO_TX_FLUSH_SHIFT        3046#define M_FIFO_RX_CNT_SHIFT          1647#define M_FIFO_RX_CNT_MASK           0x7f48#define M_FIFO_RX_THLD_SHIFT         849#define M_FIFO_RX_THLD_MASK          0x3f50 51#define S_FIFO_CTRL_OFFSET           0x1052#define S_FIFO_RX_FLUSH_SHIFT        3153#define S_FIFO_TX_FLUSH_SHIFT        3054#define S_FIFO_RX_CNT_SHIFT          1655#define S_FIFO_RX_CNT_MASK           0x7f56#define S_FIFO_RX_THLD_SHIFT         857#define S_FIFO_RX_THLD_MASK          0x3f58 59#define M_CMD_OFFSET                 0x3060#define M_CMD_START_BUSY_SHIFT       3161#define M_CMD_STATUS_SHIFT           2562#define M_CMD_STATUS_MASK            0x0763#define M_CMD_STATUS_SUCCESS         0x064#define M_CMD_STATUS_LOST_ARB        0x165#define M_CMD_STATUS_NACK_ADDR       0x266#define M_CMD_STATUS_NACK_DATA       0x367#define M_CMD_STATUS_TIMEOUT         0x468#define M_CMD_STATUS_FIFO_UNDERRUN   0x569#define M_CMD_STATUS_RX_FIFO_FULL    0x670#define M_CMD_PROTOCOL_SHIFT         971#define M_CMD_PROTOCOL_MASK          0xf72#define M_CMD_PROTOCOL_QUICK         0x073#define M_CMD_PROTOCOL_BLK_WR        0x774#define M_CMD_PROTOCOL_BLK_RD        0x875#define M_CMD_PROTOCOL_PROCESS       0xa76#define M_CMD_PEC_SHIFT              877#define M_CMD_RD_CNT_SHIFT           078#define M_CMD_RD_CNT_MASK            0xff79 80#define S_CMD_OFFSET                 0x3481#define S_CMD_START_BUSY_SHIFT       3182#define S_CMD_STATUS_SHIFT           2383#define S_CMD_STATUS_MASK            0x0784#define S_CMD_STATUS_SUCCESS         0x085#define S_CMD_STATUS_TIMEOUT         0x586#define S_CMD_STATUS_MASTER_ABORT    0x787 88#define IE_OFFSET                    0x3889#define IE_M_RX_FIFO_FULL_SHIFT      3190#define IE_M_RX_THLD_SHIFT           3091#define IE_M_START_BUSY_SHIFT        2892#define IE_M_TX_UNDERRUN_SHIFT       2793#define IE_S_RX_FIFO_FULL_SHIFT      2694#define IE_S_RX_THLD_SHIFT           2595#define IE_S_RX_EVENT_SHIFT          2496#define IE_S_START_BUSY_SHIFT        2397#define IE_S_TX_UNDERRUN_SHIFT       2298#define IE_S_RD_EVENT_SHIFT          2199 100#define IS_OFFSET                    0x3c101#define IS_M_RX_FIFO_FULL_SHIFT      31102#define IS_M_RX_THLD_SHIFT           30103#define IS_M_START_BUSY_SHIFT        28104#define IS_M_TX_UNDERRUN_SHIFT       27105#define IS_S_RX_FIFO_FULL_SHIFT      26106#define IS_S_RX_THLD_SHIFT           25107#define IS_S_RX_EVENT_SHIFT          24108#define IS_S_START_BUSY_SHIFT        23109#define IS_S_TX_UNDERRUN_SHIFT       22110#define IS_S_RD_EVENT_SHIFT          21111 112#define M_TX_OFFSET                  0x40113#define M_TX_WR_STATUS_SHIFT         31114#define M_TX_DATA_SHIFT              0115#define M_TX_DATA_MASK               0xff116 117#define M_RX_OFFSET                  0x44118#define M_RX_STATUS_SHIFT            30119#define M_RX_STATUS_MASK             0x03120#define M_RX_PEC_ERR_SHIFT           29121#define M_RX_DATA_SHIFT              0122#define M_RX_DATA_MASK               0xff123 124#define S_TX_OFFSET                  0x48125#define S_TX_WR_STATUS_SHIFT         31126#define S_TX_DATA_SHIFT              0127#define S_TX_DATA_MASK               0xff128 129#define S_RX_OFFSET                  0x4c130#define S_RX_STATUS_SHIFT            30131#define S_RX_STATUS_MASK             0x03132#define S_RX_PEC_ERR_SHIFT           29133#define S_RX_DATA_SHIFT              0134#define S_RX_DATA_MASK               0xff135 136#define I2C_TIMEOUT_MSEC             50000137#define M_TX_RX_FIFO_SIZE            64138#define M_RX_FIFO_MAX_THLD_VALUE     (M_TX_RX_FIFO_SIZE - 1)139 140#define M_RX_MAX_READ_LEN            255141#define M_RX_FIFO_THLD_VALUE         50142 143#define IE_M_ALL_INTERRUPT_SHIFT     27144#define IE_M_ALL_INTERRUPT_MASK      0x1e145 146#define SLAVE_READ_WRITE_BIT_MASK    0x1147#define SLAVE_READ_WRITE_BIT_SHIFT   0x1148#define SLAVE_MAX_SIZE_TRANSACTION   64149#define SLAVE_CLOCK_STRETCH_TIME     25150 151#define IE_S_ALL_INTERRUPT_SHIFT     21152#define IE_S_ALL_INTERRUPT_MASK      0x3f153/*154 * It takes ~18us to reading 10bytes of data, hence to keep tasklet155 * running for less time, max slave read per tasklet is set to 10 bytes.156 */157#define MAX_SLAVE_RX_PER_INT         10158 159enum i2c_slave_read_status {160	I2C_SLAVE_RX_FIFO_EMPTY = 0,161	I2C_SLAVE_RX_START,162	I2C_SLAVE_RX_DATA,163	I2C_SLAVE_RX_END,164};165 166enum bus_speed_index {167	I2C_SPD_100K = 0,168	I2C_SPD_400K,169};170 171enum bcm_iproc_i2c_type {172	IPROC_I2C,173	IPROC_I2C_NIC174};175 176struct bcm_iproc_i2c_dev {177	struct device *device;178	enum bcm_iproc_i2c_type type;179	int irq;180 181	void __iomem *base;182	void __iomem *idm_base;183 184	u32 ape_addr_mask;185 186	/* lock for indirect access through IDM */187	spinlock_t idm_lock;188 189	struct i2c_adapter adapter;190	unsigned int bus_speed;191 192	struct completion done;193	int xfer_is_done;194 195	struct i2c_msg *msg;196 197	struct i2c_client *slave;198 199	/* bytes that have been transferred */200	unsigned int tx_bytes;201	/* bytes that have been read */202	unsigned int rx_bytes;203	unsigned int thld_bytes;204 205	bool slave_rx_only;206	bool rx_start_rcvd;207	bool slave_read_complete;208	u32 tx_underrun;209	u32 slave_int_mask;210	struct tasklet_struct slave_rx_tasklet;211};212 213/* tasklet to process slave rx data */214static void slave_rx_tasklet_fn(unsigned long);215 216/*217 * Can be expanded in the future if more interrupt status bits are utilized218 */219#define ISR_MASK (BIT(IS_M_START_BUSY_SHIFT) | BIT(IS_M_TX_UNDERRUN_SHIFT)\220		| BIT(IS_M_RX_THLD_SHIFT))221 222#define ISR_MASK_SLAVE (BIT(IS_S_START_BUSY_SHIFT)\223		| BIT(IS_S_RX_EVENT_SHIFT) | BIT(IS_S_RD_EVENT_SHIFT)\224		| BIT(IS_S_TX_UNDERRUN_SHIFT) | BIT(IS_S_RX_FIFO_FULL_SHIFT)\225		| BIT(IS_S_RX_THLD_SHIFT))226 227static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave);228static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave);229static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,230					 bool enable);231 232static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c,233				   u32 offset)234{235	u32 val;236	unsigned long flags;237 238	if (iproc_i2c->idm_base) {239		spin_lock_irqsave(&iproc_i2c->idm_lock, flags);240		writel(iproc_i2c->ape_addr_mask,241		       iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);242		val = readl(iproc_i2c->base + offset);243		spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags);244	} else {245		val = readl(iproc_i2c->base + offset);246	}247 248	return val;249}250 251static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c,252				    u32 offset, u32 val)253{254	unsigned long flags;255 256	if (iproc_i2c->idm_base) {257		spin_lock_irqsave(&iproc_i2c->idm_lock, flags);258		writel(iproc_i2c->ape_addr_mask,259		       iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);260		writel(val, iproc_i2c->base + offset);261		spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags);262	} else {263		writel(val, iproc_i2c->base + offset);264	}265}266 267static void bcm_iproc_i2c_slave_init(268	struct bcm_iproc_i2c_dev *iproc_i2c, bool need_reset)269{270	u32 val;271 272	iproc_i2c->tx_underrun = 0;273	if (need_reset) {274		/* put controller in reset */275		val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);276		val |= BIT(CFG_RESET_SHIFT);277		iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);278 279		/* wait 100 usec per spec */280		udelay(100);281 282		/* bring controller out of reset */283		val &= ~(BIT(CFG_RESET_SHIFT));284		iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);285	}286 287	/* flush TX/RX FIFOs */288	val = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));289	iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val);290 291	/* Maximum slave stretch time */292	val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);293	val &= ~(TIM_RAND_SLAVE_STRETCH_MASK << TIM_RAND_SLAVE_STRETCH_SHIFT);294	val |= (SLAVE_CLOCK_STRETCH_TIME << TIM_RAND_SLAVE_STRETCH_SHIFT);295	iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);296 297	/* Configure the slave address */298	val = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);299	val |= BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);300	val &= ~(S_CFG_NIC_SMB_ADDR3_MASK << S_CFG_NIC_SMB_ADDR3_SHIFT);301	val |= (iproc_i2c->slave->addr << S_CFG_NIC_SMB_ADDR3_SHIFT);302	iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, val);303 304	/* clear all pending slave interrupts */305	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE);306 307	/* Enable interrupt register to indicate a valid byte in receive fifo */308	val = BIT(IE_S_RX_EVENT_SHIFT);309	/* Enable interrupt register to indicate Slave Rx FIFO Full */310	val |= BIT(IE_S_RX_FIFO_FULL_SHIFT);311	/* Enable interrupt register to indicate a Master read transaction */312	val |= BIT(IE_S_RD_EVENT_SHIFT);313	/* Enable interrupt register for the Slave BUSY command */314	val |= BIT(IE_S_START_BUSY_SHIFT);315	iproc_i2c->slave_int_mask = val;316	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);317}318 319static bool bcm_iproc_i2c_check_slave_status320	(struct bcm_iproc_i2c_dev *iproc_i2c, u32 status)321{322	u32 val;323	bool recover = false;324 325	/* check slave transmit status only if slave is transmitting */326	if (!iproc_i2c->slave_rx_only) {327		val = iproc_i2c_rd_reg(iproc_i2c, S_CMD_OFFSET);328		/* status is valid only when START_BUSY is cleared */329		if (!(val & BIT(S_CMD_START_BUSY_SHIFT))) {330			val = (val >> S_CMD_STATUS_SHIFT) & S_CMD_STATUS_MASK;331			if (val == S_CMD_STATUS_TIMEOUT ||332			    val == S_CMD_STATUS_MASTER_ABORT) {333				dev_warn(iproc_i2c->device,334					 (val == S_CMD_STATUS_TIMEOUT) ?335					 "slave random stretch time timeout\n" :336					 "Master aborted read transaction\n");337				recover = true;338			}339		}340	}341 342	/* RX_EVENT is not valid when START_BUSY is set */343	if ((status & BIT(IS_S_RX_EVENT_SHIFT)) &&344	    (status & BIT(IS_S_START_BUSY_SHIFT))) {345		dev_warn(iproc_i2c->device, "Slave aborted read transaction\n");346		recover = true;347	}348 349	if (recover) {350		/* re-initialize i2c for recovery */351		bcm_iproc_i2c_enable_disable(iproc_i2c, false);352		bcm_iproc_i2c_slave_init(iproc_i2c, true);353		bcm_iproc_i2c_enable_disable(iproc_i2c, true);354	}355 356	return recover;357}358 359static void bcm_iproc_i2c_slave_read(struct bcm_iproc_i2c_dev *iproc_i2c)360{361	u8 rx_data, rx_status;362	u32 rx_bytes = 0;363	u32 val;364 365	while (rx_bytes < MAX_SLAVE_RX_PER_INT) {366		val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET);367		rx_status = (val >> S_RX_STATUS_SHIFT) & S_RX_STATUS_MASK;368		rx_data = ((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK);369 370		if (rx_status == I2C_SLAVE_RX_START) {371			/* Start of SMBUS Master write */372			i2c_slave_event(iproc_i2c->slave,373					I2C_SLAVE_WRITE_REQUESTED, &rx_data);374			iproc_i2c->rx_start_rcvd = true;375			iproc_i2c->slave_read_complete = false;376		} else if (rx_status == I2C_SLAVE_RX_DATA &&377			   iproc_i2c->rx_start_rcvd) {378			/* Middle of SMBUS Master write */379			i2c_slave_event(iproc_i2c->slave,380					I2C_SLAVE_WRITE_RECEIVED, &rx_data);381		} else if (rx_status == I2C_SLAVE_RX_END &&382			   iproc_i2c->rx_start_rcvd) {383			/* End of SMBUS Master write */384			if (iproc_i2c->slave_rx_only)385				i2c_slave_event(iproc_i2c->slave,386						I2C_SLAVE_WRITE_RECEIVED,387						&rx_data);388 389			i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP,390					&rx_data);391		} else if (rx_status == I2C_SLAVE_RX_FIFO_EMPTY) {392			iproc_i2c->rx_start_rcvd = false;393			iproc_i2c->slave_read_complete = true;394			break;395		}396 397		rx_bytes++;398	}399}400 401static void slave_rx_tasklet_fn(unsigned long data)402{403	struct bcm_iproc_i2c_dev *iproc_i2c = (struct bcm_iproc_i2c_dev *)data;404	u32 int_clr;405 406	bcm_iproc_i2c_slave_read(iproc_i2c);407 408	/* clear pending IS_S_RX_EVENT_SHIFT interrupt */409	int_clr = BIT(IS_S_RX_EVENT_SHIFT);410 411	if (!iproc_i2c->slave_rx_only && iproc_i2c->slave_read_complete) {412		/*413		 * In case of single byte master-read request,414		 * IS_S_TX_UNDERRUN_SHIFT event is generated before415		 * IS_S_START_BUSY_SHIFT event. Hence start slave data send416		 * from first IS_S_TX_UNDERRUN_SHIFT event.417		 *418		 * This means don't send any data from slave when419		 * IS_S_RD_EVENT_SHIFT event is generated else it will increment420		 * eeprom or other backend slave driver read pointer twice.421		 */422		iproc_i2c->tx_underrun = 0;423		iproc_i2c->slave_int_mask |= BIT(IE_S_TX_UNDERRUN_SHIFT);424 425		/* clear IS_S_RD_EVENT_SHIFT interrupt */426		int_clr |= BIT(IS_S_RD_EVENT_SHIFT);427	}428 429	/* clear slave interrupt */430	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, int_clr);431	/* enable slave interrupts */432	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, iproc_i2c->slave_int_mask);433}434 435static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c,436				    u32 status)437{438	u32 val;439	u8 value;440 441 442	if (status & BIT(IS_S_TX_UNDERRUN_SHIFT)) {443		iproc_i2c->tx_underrun++;444		if (iproc_i2c->tx_underrun == 1)445			/* Start of SMBUS for Master Read */446			i2c_slave_event(iproc_i2c->slave,447					I2C_SLAVE_READ_REQUESTED,448					&value);449		else450			/* Master read other than start */451			i2c_slave_event(iproc_i2c->slave,452					I2C_SLAVE_READ_PROCESSED,453					&value);454 455		iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value);456		/* start transfer */457		val = BIT(S_CMD_START_BUSY_SHIFT);458		iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);459 460		/* clear interrupt */461		iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET,462				 BIT(IS_S_TX_UNDERRUN_SHIFT));463	}464 465	/* Stop received from master in case of master read transaction */466	if (status & BIT(IS_S_START_BUSY_SHIFT)) {467		/*468		 * Disable interrupt for TX FIFO becomes empty and469		 * less than PKT_LENGTH bytes were output on the SMBUS470		 */471		iproc_i2c->slave_int_mask &= ~BIT(IE_S_TX_UNDERRUN_SHIFT);472		val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);473		val &= ~BIT(IE_S_TX_UNDERRUN_SHIFT);474		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);475 476		/* End of SMBUS for Master Read */477		val = BIT(S_TX_WR_STATUS_SHIFT);478		iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, val);479 480		val = BIT(S_CMD_START_BUSY_SHIFT);481		iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);482 483		/* flush TX FIFOs */484		val = iproc_i2c_rd_reg(iproc_i2c, S_FIFO_CTRL_OFFSET);485		val |= (BIT(S_FIFO_TX_FLUSH_SHIFT));486		iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val);487 488		i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP, &value);489 490		/* clear interrupt */491		iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET,492				 BIT(IS_S_START_BUSY_SHIFT));493	}494 495	/* if the controller has been reset, immediately return from the ISR */496	if (bcm_iproc_i2c_check_slave_status(iproc_i2c, status))497		return true;498 499	/*500	 * Slave events in case of master-write, master-write-read and,501	 * master-read502	 *503	 * Master-write     : only IS_S_RX_EVENT_SHIFT event504	 * Master-write-read: both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT505	 *                    events506	 * Master-read      : both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT507	 *                    events or only IS_S_RD_EVENT_SHIFT508	 *509	 * iproc has a slave rx fifo size of 64 bytes. Rx fifo full interrupt510	 * (IS_S_RX_FIFO_FULL_SHIFT) will be generated when RX fifo becomes511	 * full. This can happen if Master issues write requests of more than512	 * 64 bytes.513	 */514	if (status & BIT(IS_S_RX_EVENT_SHIFT) ||515	    status & BIT(IS_S_RD_EVENT_SHIFT) ||516	    status & BIT(IS_S_RX_FIFO_FULL_SHIFT)) {517		/* disable slave interrupts */518		val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);519		val &= ~iproc_i2c->slave_int_mask;520		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);521 522		if (status & BIT(IS_S_RD_EVENT_SHIFT))523			/* Master-write-read request */524			iproc_i2c->slave_rx_only = false;525		else526			/* Master-write request only */527			iproc_i2c->slave_rx_only = true;528 529		/* schedule tasklet to read data later */530		tasklet_schedule(&iproc_i2c->slave_rx_tasklet);531 532		/* clear IS_S_RX_FIFO_FULL_SHIFT interrupt */533		if (status & BIT(IS_S_RX_FIFO_FULL_SHIFT)) {534			val = BIT(IS_S_RX_FIFO_FULL_SHIFT);535			iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, val);536		}537	}538 539	return true;540}541 542static void bcm_iproc_i2c_read_valid_bytes(struct bcm_iproc_i2c_dev *iproc_i2c)543{544	struct i2c_msg *msg = iproc_i2c->msg;545	uint32_t val;546 547	/* Read valid data from RX FIFO */548	while (iproc_i2c->rx_bytes < msg->len) {549		val = iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET);550 551		/* rx fifo empty */552		if (!((val >> M_RX_STATUS_SHIFT) & M_RX_STATUS_MASK))553			break;554 555		msg->buf[iproc_i2c->rx_bytes] =556			(val >> M_RX_DATA_SHIFT) & M_RX_DATA_MASK;557		iproc_i2c->rx_bytes++;558	}559}560 561static void bcm_iproc_i2c_send(struct bcm_iproc_i2c_dev *iproc_i2c)562{563	struct i2c_msg *msg = iproc_i2c->msg;564	unsigned int tx_bytes = msg->len - iproc_i2c->tx_bytes;565	unsigned int i;566	u32 val;567 568	/* can only fill up to the FIFO size */569	tx_bytes = min_t(unsigned int, tx_bytes, M_TX_RX_FIFO_SIZE);570	for (i = 0; i < tx_bytes; i++) {571		/* start from where we left over */572		unsigned int idx = iproc_i2c->tx_bytes + i;573 574		val = msg->buf[idx];575 576		/* mark the last byte */577		if (idx == msg->len - 1) {578			val |= BIT(M_TX_WR_STATUS_SHIFT);579 580			if (iproc_i2c->irq) {581				u32 tmp;582 583				/*584				 * Since this is the last byte, we should now585				 * disable TX FIFO underrun interrupt586				 */587				tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);588				tmp &= ~BIT(IE_M_TX_UNDERRUN_SHIFT);589				iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET,590						 tmp);591			}592		}593 594		/* load data into TX FIFO */595		iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);596	}597 598	/* update number of transferred bytes */599	iproc_i2c->tx_bytes += tx_bytes;600}601 602static void bcm_iproc_i2c_read(struct bcm_iproc_i2c_dev *iproc_i2c)603{604	struct i2c_msg *msg = iproc_i2c->msg;605	u32 bytes_left, val;606 607	bcm_iproc_i2c_read_valid_bytes(iproc_i2c);608	bytes_left = msg->len - iproc_i2c->rx_bytes;609	if (bytes_left == 0) {610		if (iproc_i2c->irq) {611			/* finished reading all data, disable rx thld event */612			val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);613			val &= ~BIT(IS_M_RX_THLD_SHIFT);614			iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);615		}616	} else if (bytes_left < iproc_i2c->thld_bytes) {617		/* set bytes left as threshold */618		val = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);619		val &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);620		val |= (bytes_left << M_FIFO_RX_THLD_SHIFT);621		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);622		iproc_i2c->thld_bytes = bytes_left;623	}624	/*625	 * bytes_left >= iproc_i2c->thld_bytes,626	 * hence no need to change the THRESHOLD SET.627	 * It will remain as iproc_i2c->thld_bytes itself628	 */629}630 631static void bcm_iproc_i2c_process_m_event(struct bcm_iproc_i2c_dev *iproc_i2c,632					  u32 status)633{634	/* TX FIFO is empty and we have more data to send */635	if (status & BIT(IS_M_TX_UNDERRUN_SHIFT))636		bcm_iproc_i2c_send(iproc_i2c);637 638	/* RX FIFO threshold is reached and data needs to be read out */639	if (status & BIT(IS_M_RX_THLD_SHIFT))640		bcm_iproc_i2c_read(iproc_i2c);641 642	/* transfer is done */643	if (status & BIT(IS_M_START_BUSY_SHIFT)) {644		iproc_i2c->xfer_is_done = 1;645		if (iproc_i2c->irq)646			complete(&iproc_i2c->done);647	}648}649 650static irqreturn_t bcm_iproc_i2c_isr(int irq, void *data)651{652	struct bcm_iproc_i2c_dev *iproc_i2c = data;653	u32 slave_status;654	u32 status;655	bool ret;656 657	status = iproc_i2c_rd_reg(iproc_i2c, IS_OFFSET);658	/* process only slave interrupt which are enabled */659	slave_status = status & iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET) &660		       ISR_MASK_SLAVE;661 662	if (slave_status) {663		ret = bcm_iproc_i2c_slave_isr(iproc_i2c, slave_status);664		if (ret)665			return IRQ_HANDLED;666		else667			return IRQ_NONE;668	}669 670	status &= ISR_MASK;671	if (!status)672		return IRQ_NONE;673 674	/* process all master based events */675	bcm_iproc_i2c_process_m_event(iproc_i2c, status);676	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);677 678	return IRQ_HANDLED;679}680 681static int bcm_iproc_i2c_init(struct bcm_iproc_i2c_dev *iproc_i2c)682{683	u32 val;684 685	/* put controller in reset */686	val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);687	val |= BIT(CFG_RESET_SHIFT);688	val &= ~(BIT(CFG_EN_SHIFT));689	iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);690 691	/* wait 100 usec per spec */692	udelay(100);693 694	/* bring controller out of reset */695	val &= ~(BIT(CFG_RESET_SHIFT));696	iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);697 698	/* flush TX/RX FIFOs and set RX FIFO threshold to zero */699	val = (BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT));700	iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);701	/* disable all interrupts */702	val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);703	val &= ~(IE_M_ALL_INTERRUPT_MASK <<704			IE_M_ALL_INTERRUPT_SHIFT);705	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);706 707	/* clear all pending interrupts */708	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, 0xffffffff);709 710	return 0;711}712 713static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,714					 bool enable)715{716	u32 val;717 718	val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);719	if (enable)720		val |= BIT(CFG_EN_SHIFT);721	else722		val &= ~BIT(CFG_EN_SHIFT);723	iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);724}725 726static int bcm_iproc_i2c_check_status(struct bcm_iproc_i2c_dev *iproc_i2c,727				      struct i2c_msg *msg)728{729	u32 val;730 731	val = iproc_i2c_rd_reg(iproc_i2c, M_CMD_OFFSET);732	val = (val >> M_CMD_STATUS_SHIFT) & M_CMD_STATUS_MASK;733 734	switch (val) {735	case M_CMD_STATUS_SUCCESS:736		return 0;737 738	case M_CMD_STATUS_LOST_ARB:739		dev_dbg(iproc_i2c->device, "lost bus arbitration\n");740		return -EAGAIN;741 742	case M_CMD_STATUS_NACK_ADDR:743		dev_dbg(iproc_i2c->device, "NAK addr:0x%02x\n", msg->addr);744		return -ENXIO;745 746	case M_CMD_STATUS_NACK_DATA:747		dev_dbg(iproc_i2c->device, "NAK data\n");748		return -ENXIO;749 750	case M_CMD_STATUS_TIMEOUT:751		dev_dbg(iproc_i2c->device, "bus timeout\n");752		return -ETIMEDOUT;753 754	case M_CMD_STATUS_FIFO_UNDERRUN:755		dev_dbg(iproc_i2c->device, "FIFO under-run\n");756		return -ENXIO;757 758	case M_CMD_STATUS_RX_FIFO_FULL:759		dev_dbg(iproc_i2c->device, "RX FIFO full\n");760		return -ETIMEDOUT;761 762	default:763		dev_dbg(iproc_i2c->device, "unknown error code=%d\n", val);764 765		/* re-initialize i2c for recovery */766		bcm_iproc_i2c_enable_disable(iproc_i2c, false);767		bcm_iproc_i2c_init(iproc_i2c);768		bcm_iproc_i2c_enable_disable(iproc_i2c, true);769 770		return -EIO;771	}772}773 774static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,775				   struct i2c_msg *msg,776				   u32 cmd)777{778	unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT_MSEC);779	u32 val, status;780	int ret;781 782	iproc_i2c_wr_reg(iproc_i2c, M_CMD_OFFSET, cmd);783 784	if (iproc_i2c->irq) {785		time_left = wait_for_completion_timeout(&iproc_i2c->done,786							time_left);787		/* disable all interrupts */788		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);789		/* read it back to flush the write */790		iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);791		/* make sure the interrupt handler isn't running */792		synchronize_irq(iproc_i2c->irq);793 794	} else { /* polling mode */795		unsigned long timeout = jiffies + time_left;796 797		do {798			status = iproc_i2c_rd_reg(iproc_i2c,799						  IS_OFFSET) & ISR_MASK;800			bcm_iproc_i2c_process_m_event(iproc_i2c, status);801			iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);802 803			if (time_after(jiffies, timeout)) {804				time_left = 0;805				break;806			}807 808			cpu_relax();809			cond_resched();810		} while (!iproc_i2c->xfer_is_done);811	}812 813	if (!time_left && !iproc_i2c->xfer_is_done) {814		/* flush both TX/RX FIFOs */815		val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);816		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);817		return -ETIMEDOUT;818	}819 820	ret = bcm_iproc_i2c_check_status(iproc_i2c, msg);821	if (ret) {822		/* flush both TX/RX FIFOs */823		val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);824		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);825		return ret;826	}827 828	return 0;829}830 831/*832 * If 'process_call' is true, then this is a multi-msg transfer that requires833 * a repeated start between the messages.834 * More specifically, it must be a write (reg) followed by a read (data).835 * The i2c quirks are set to enforce this rule.836 */837static int bcm_iproc_i2c_xfer_internal(struct bcm_iproc_i2c_dev *iproc_i2c,838					struct i2c_msg *msgs, bool process_call)839{840	int i;841	u8 addr;842	u32 val, tmp, val_intr_en;843	unsigned int tx_bytes;844	struct i2c_msg *msg = &msgs[0];845 846	/* check if bus is busy */847	if (!!(iproc_i2c_rd_reg(iproc_i2c,848				M_CMD_OFFSET) & BIT(M_CMD_START_BUSY_SHIFT))) {849		dev_warn(iproc_i2c->device, "bus is busy\n");850		return -EBUSY;851	}852 853	iproc_i2c->msg = msg;854 855	/* format and load slave address into the TX FIFO */856	addr = i2c_8bit_addr_from_msg(msg);857	iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, addr);858 859	/*860	 * For a write transaction, load data into the TX FIFO. Only allow861	 * loading up to TX FIFO size - 1 bytes of data since the first byte862	 * has been used up by the slave address863	 */864	tx_bytes = min_t(unsigned int, msg->len, M_TX_RX_FIFO_SIZE - 1);865	if (!(msg->flags & I2C_M_RD)) {866		for (i = 0; i < tx_bytes; i++) {867			val = msg->buf[i];868 869			/* mark the last byte */870			if (!process_call && (i == msg->len - 1))871				val |= BIT(M_TX_WR_STATUS_SHIFT);872 873			iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);874		}875		iproc_i2c->tx_bytes = tx_bytes;876	}877 878	/* Process the read message if this is process call */879	if (process_call) {880		msg++;881		iproc_i2c->msg = msg;  /* point to second msg */882 883		/*884		 * The last byte to be sent out should be a slave885		 * address with read operation886		 */887		addr = i2c_8bit_addr_from_msg(msg);888		/* mark it the last byte out */889		val = addr | BIT(M_TX_WR_STATUS_SHIFT);890		iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);891	}892 893	/* mark as incomplete before starting the transaction */894	if (iproc_i2c->irq)895		reinit_completion(&iproc_i2c->done);896 897	iproc_i2c->xfer_is_done = 0;898 899	/*900	 * Enable the "start busy" interrupt, which will be triggered after the901	 * transaction is done, i.e., the internal start_busy bit, transitions902	 * from 1 to 0.903	 */904	val_intr_en = BIT(IE_M_START_BUSY_SHIFT);905 906	/*907	 * If TX data size is larger than the TX FIFO, need to enable TX908	 * underrun interrupt, which will be triggerred when the TX FIFO is909	 * empty. When that happens we can then pump more data into the FIFO910	 */911	if (!process_call && !(msg->flags & I2C_M_RD) &&912	    msg->len > iproc_i2c->tx_bytes)913		val_intr_en |= BIT(IE_M_TX_UNDERRUN_SHIFT);914 915	/*916	 * Now we can activate the transfer. For a read operation, specify the917	 * number of bytes to read918	 */919	val = BIT(M_CMD_START_BUSY_SHIFT);920 921	if (msg->len == 0) {922		/* SMBUS QUICK Command (Read/Write) */923		val |= (M_CMD_PROTOCOL_QUICK << M_CMD_PROTOCOL_SHIFT);924	} else if (msg->flags & I2C_M_RD) {925		u32 protocol;926 927		iproc_i2c->rx_bytes = 0;928		if (msg->len > M_RX_FIFO_MAX_THLD_VALUE)929			iproc_i2c->thld_bytes = M_RX_FIFO_THLD_VALUE;930		else931			iproc_i2c->thld_bytes = msg->len;932 933		/* set threshold value */934		tmp = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);935		tmp &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);936		tmp |= iproc_i2c->thld_bytes << M_FIFO_RX_THLD_SHIFT;937		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, tmp);938 939		/* enable the RX threshold interrupt */940		val_intr_en |= BIT(IE_M_RX_THLD_SHIFT);941 942		protocol = process_call ?943				M_CMD_PROTOCOL_PROCESS : M_CMD_PROTOCOL_BLK_RD;944 945		val |= (protocol << M_CMD_PROTOCOL_SHIFT) |946		       (msg->len << M_CMD_RD_CNT_SHIFT);947	} else {948		val |= (M_CMD_PROTOCOL_BLK_WR << M_CMD_PROTOCOL_SHIFT);949	}950 951	if (iproc_i2c->irq)952		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val_intr_en);953 954	return bcm_iproc_i2c_xfer_wait(iproc_i2c, msg, val);955}956 957static int bcm_iproc_i2c_xfer(struct i2c_adapter *adapter,958			      struct i2c_msg msgs[], int num)959{960	struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adapter);961	bool process_call = false;962	int ret;963 964	if (num == 2) {965		/* Repeated start, use process call */966		process_call = true;967		if (msgs[1].flags & I2C_M_NOSTART) {968			dev_err(iproc_i2c->device, "Invalid repeated start\n");969			return -EOPNOTSUPP;970		}971	}972 973	ret = bcm_iproc_i2c_xfer_internal(iproc_i2c, msgs, process_call);974	if (ret) {975		dev_dbg(iproc_i2c->device, "xfer failed\n");976		return ret;977	}978 979	return num;980}981 982static uint32_t bcm_iproc_i2c_functionality(struct i2c_adapter *adap)983{984	u32 val;985 986	val = I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;987 988	if (adap->algo->reg_slave)989		val |= I2C_FUNC_SLAVE;990 991	return val;992}993 994static struct i2c_algorithm bcm_iproc_algo = {995	.master_xfer = bcm_iproc_i2c_xfer,996	.functionality = bcm_iproc_i2c_functionality,997	.reg_slave = bcm_iproc_i2c_reg_slave,998	.unreg_slave = bcm_iproc_i2c_unreg_slave,999};1000 1001static const struct i2c_adapter_quirks bcm_iproc_i2c_quirks = {1002	.flags = I2C_AQ_COMB_WRITE_THEN_READ,1003	.max_comb_1st_msg_len = M_TX_RX_FIFO_SIZE,1004	.max_read_len = M_RX_MAX_READ_LEN,1005};1006 1007static int bcm_iproc_i2c_cfg_speed(struct bcm_iproc_i2c_dev *iproc_i2c)1008{1009	unsigned int bus_speed;1010	u32 val;1011	int ret = of_property_read_u32(iproc_i2c->device->of_node,1012				       "clock-frequency", &bus_speed);1013	if (ret < 0) {1014		dev_info(iproc_i2c->device,1015			"unable to interpret clock-frequency DT property\n");1016		bus_speed = I2C_MAX_STANDARD_MODE_FREQ;1017	}1018 1019	if (bus_speed < I2C_MAX_STANDARD_MODE_FREQ) {1020		dev_err(iproc_i2c->device, "%d Hz bus speed not supported\n",1021			bus_speed);1022		dev_err(iproc_i2c->device,1023			"valid speeds are 100khz and 400khz\n");1024		return -EINVAL;1025	} else if (bus_speed < I2C_MAX_FAST_MODE_FREQ) {1026		bus_speed = I2C_MAX_STANDARD_MODE_FREQ;1027	} else {1028		bus_speed = I2C_MAX_FAST_MODE_FREQ;1029	}1030 1031	iproc_i2c->bus_speed = bus_speed;1032	val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);1033	val &= ~BIT(TIM_CFG_MODE_400_SHIFT);1034	val |= (bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;1035	iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);1036 1037	dev_info(iproc_i2c->device, "bus set to %u Hz\n", bus_speed);1038 1039	return 0;1040}1041 1042static int bcm_iproc_i2c_probe(struct platform_device *pdev)1043{1044	int irq, ret = 0;1045	struct bcm_iproc_i2c_dev *iproc_i2c;1046	struct i2c_adapter *adap;1047 1048	iproc_i2c = devm_kzalloc(&pdev->dev, sizeof(*iproc_i2c),1049				 GFP_KERNEL);1050	if (!iproc_i2c)1051		return -ENOMEM;1052 1053	platform_set_drvdata(pdev, iproc_i2c);1054	iproc_i2c->device = &pdev->dev;1055	iproc_i2c->type =1056		(enum bcm_iproc_i2c_type)of_device_get_match_data(&pdev->dev);1057	init_completion(&iproc_i2c->done);1058 1059	iproc_i2c->base = devm_platform_ioremap_resource(pdev, 0);1060	if (IS_ERR(iproc_i2c->base))1061		return PTR_ERR(iproc_i2c->base);1062 1063	if (iproc_i2c->type == IPROC_I2C_NIC) {1064		iproc_i2c->idm_base = devm_platform_ioremap_resource(pdev, 1);1065		if (IS_ERR(iproc_i2c->idm_base))1066			return PTR_ERR(iproc_i2c->idm_base);1067 1068		ret = of_property_read_u32(iproc_i2c->device->of_node,1069					   "brcm,ape-hsls-addr-mask",1070					   &iproc_i2c->ape_addr_mask);1071		if (ret < 0) {1072			dev_err(iproc_i2c->device,1073				"'brcm,ape-hsls-addr-mask' missing\n");1074			return -EINVAL;1075		}1076 1077		spin_lock_init(&iproc_i2c->idm_lock);1078 1079		/* no slave support */1080		bcm_iproc_algo.reg_slave = NULL;1081		bcm_iproc_algo.unreg_slave = NULL;1082	}1083 1084	ret = bcm_iproc_i2c_init(iproc_i2c);1085	if (ret)1086		return ret;1087 1088	ret = bcm_iproc_i2c_cfg_speed(iproc_i2c);1089	if (ret)1090		return ret;1091 1092	irq = platform_get_irq(pdev, 0);1093	if (irq > 0) {1094		ret = devm_request_irq(iproc_i2c->device, irq,1095				       bcm_iproc_i2c_isr, 0, pdev->name,1096				       iproc_i2c);1097		if (ret < 0) {1098			dev_err(iproc_i2c->device,1099				"unable to request irq %i\n", irq);1100			return ret;1101		}1102 1103		iproc_i2c->irq = irq;1104	} else {1105		dev_warn(iproc_i2c->device,1106			 "no irq resource, falling back to poll mode\n");1107	}1108 1109	bcm_iproc_i2c_enable_disable(iproc_i2c, true);1110 1111	adap = &iproc_i2c->adapter;1112	i2c_set_adapdata(adap, iproc_i2c);1113	snprintf(adap->name, sizeof(adap->name),1114		"Broadcom iProc (%s)",1115		of_node_full_name(iproc_i2c->device->of_node));1116	adap->algo = &bcm_iproc_algo;1117	adap->quirks = &bcm_iproc_i2c_quirks;1118	adap->dev.parent = &pdev->dev;1119	adap->dev.of_node = pdev->dev.of_node;1120 1121	return i2c_add_adapter(adap);1122}1123 1124static void bcm_iproc_i2c_remove(struct platform_device *pdev)1125{1126	struct bcm_iproc_i2c_dev *iproc_i2c = platform_get_drvdata(pdev);1127 1128	if (iproc_i2c->irq) {1129		/*1130		 * Make sure there's no pending interrupt when we remove the1131		 * adapter1132		 */1133		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);1134		iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);1135		synchronize_irq(iproc_i2c->irq);1136	}1137 1138	i2c_del_adapter(&iproc_i2c->adapter);1139	bcm_iproc_i2c_enable_disable(iproc_i2c, false);1140}1141 1142static int bcm_iproc_i2c_suspend(struct device *dev)1143{1144	struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);1145 1146	if (iproc_i2c->irq) {1147		/*1148		 * Make sure there's no pending interrupt when we go into1149		 * suspend1150		 */1151		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);1152		iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);1153		synchronize_irq(iproc_i2c->irq);1154	}1155 1156	/* now disable the controller */1157	bcm_iproc_i2c_enable_disable(iproc_i2c, false);1158 1159	return 0;1160}1161 1162static int bcm_iproc_i2c_resume(struct device *dev)1163{1164	struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);1165	int ret;1166	u32 val;1167 1168	/*1169	 * Power domain could have been shut off completely in system deep1170	 * sleep, so re-initialize the block here1171	 */1172	ret = bcm_iproc_i2c_init(iproc_i2c);1173	if (ret)1174		return ret;1175 1176	/* configure to the desired bus speed */1177	val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);1178	val &= ~BIT(TIM_CFG_MODE_400_SHIFT);1179	val |= (iproc_i2c->bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;1180	iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);1181 1182	bcm_iproc_i2c_enable_disable(iproc_i2c, true);1183 1184	return 0;1185}1186 1187static const struct dev_pm_ops bcm_iproc_i2c_pm_ops = {1188	.suspend_late = &bcm_iproc_i2c_suspend,1189	.resume_early = &bcm_iproc_i2c_resume1190};1191 1192static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave)1193{1194	struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);1195 1196	if (iproc_i2c->slave)1197		return -EBUSY;1198 1199	if (slave->flags & I2C_CLIENT_TEN)1200		return -EAFNOSUPPORT;1201 1202	iproc_i2c->slave = slave;1203 1204	tasklet_init(&iproc_i2c->slave_rx_tasklet, slave_rx_tasklet_fn,1205		     (unsigned long)iproc_i2c);1206 1207	bcm_iproc_i2c_slave_init(iproc_i2c, false);1208	return 0;1209}1210 1211static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave)1212{1213	u32 tmp;1214	struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);1215 1216	if (!iproc_i2c->slave)1217		return -EINVAL;1218 1219	disable_irq(iproc_i2c->irq);1220 1221	tasklet_kill(&iproc_i2c->slave_rx_tasklet);1222 1223	/* disable all slave interrupts */1224	tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);1225	tmp &= ~(IE_S_ALL_INTERRUPT_MASK <<1226			IE_S_ALL_INTERRUPT_SHIFT);1227	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, tmp);1228 1229	/* Erase the slave address programmed */1230	tmp = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);1231	tmp &= ~BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);1232	iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, tmp);1233 1234	/* flush TX/RX FIFOs */1235	tmp = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));1236	iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, tmp);1237 1238	/* clear all pending slave interrupts */1239	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE);1240 1241	iproc_i2c->slave = NULL;1242 1243	enable_irq(iproc_i2c->irq);1244 1245	return 0;1246}1247 1248static const struct of_device_id bcm_iproc_i2c_of_match[] = {1249	{1250		.compatible = "brcm,iproc-i2c",1251		.data = (int *)IPROC_I2C,1252	}, {1253		.compatible = "brcm,iproc-nic-i2c",1254		.data = (int *)IPROC_I2C_NIC,1255	},1256	{ /* sentinel */ }1257};1258MODULE_DEVICE_TABLE(of, bcm_iproc_i2c_of_match);1259 1260static struct platform_driver bcm_iproc_i2c_driver = {1261	.driver = {1262		.name = "bcm-iproc-i2c",1263		.of_match_table = bcm_iproc_i2c_of_match,1264		.pm = pm_sleep_ptr(&bcm_iproc_i2c_pm_ops),1265	},1266	.probe = bcm_iproc_i2c_probe,1267	.remove_new = bcm_iproc_i2c_remove,1268};1269module_platform_driver(bcm_iproc_i2c_driver);1270 1271MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>");1272MODULE_DESCRIPTION("Broadcom iProc I2C Driver");1273MODULE_LICENSE("GPL v2");1274