2 * Copyright (C) 2014 Broadcom Corporation
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation version 2.
8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9 * kind, whether express or implied; without even the implied warranty
10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
14 #include <linux/delay.h>
15 #include <linux/i2c.h>
16 #include <linux/interrupt.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/of_device.h>
21 #include <linux/platform_device.h>
22 #include <linux/slab.h>
24 #define IDM_CTRL_DIRECT_OFFSET 0x00
25 #define CFG_OFFSET 0x00
26 #define CFG_RESET_SHIFT 31
27 #define CFG_EN_SHIFT 30
28 #define CFG_SLAVE_ADDR_0_SHIFT 28
29 #define CFG_M_RETRY_CNT_SHIFT 16
30 #define CFG_M_RETRY_CNT_MASK 0x0f
32 #define TIM_CFG_OFFSET 0x04
33 #define TIM_CFG_MODE_400_SHIFT 31
34 #define TIM_RAND_SLAVE_STRETCH_SHIFT 24
35 #define TIM_RAND_SLAVE_STRETCH_MASK 0x7f
36 #define TIM_PERIODIC_SLAVE_STRETCH_SHIFT 16
37 #define TIM_PERIODIC_SLAVE_STRETCH_MASK 0x7f
39 #define S_CFG_SMBUS_ADDR_OFFSET 0x08
40 #define S_CFG_EN_NIC_SMB_ADDR3_SHIFT 31
41 #define S_CFG_NIC_SMB_ADDR3_SHIFT 24
42 #define S_CFG_NIC_SMB_ADDR3_MASK 0x7f
43 #define S_CFG_EN_NIC_SMB_ADDR2_SHIFT 23
44 #define S_CFG_NIC_SMB_ADDR2_SHIFT 16
45 #define S_CFG_NIC_SMB_ADDR2_MASK 0x7f
46 #define S_CFG_EN_NIC_SMB_ADDR1_SHIFT 15
47 #define S_CFG_NIC_SMB_ADDR1_SHIFT 8
48 #define S_CFG_NIC_SMB_ADDR1_MASK 0x7f
49 #define S_CFG_EN_NIC_SMB_ADDR0_SHIFT 7
50 #define S_CFG_NIC_SMB_ADDR0_SHIFT 0
51 #define S_CFG_NIC_SMB_ADDR0_MASK 0x7f
53 #define M_FIFO_CTRL_OFFSET 0x0c
54 #define M_FIFO_RX_FLUSH_SHIFT 31
55 #define M_FIFO_TX_FLUSH_SHIFT 30
56 #define M_FIFO_RX_CNT_SHIFT 16
57 #define M_FIFO_RX_CNT_MASK 0x7f
58 #define M_FIFO_RX_THLD_SHIFT 8
59 #define M_FIFO_RX_THLD_MASK 0x3f
61 #define S_FIFO_CTRL_OFFSET 0x10
62 #define S_FIFO_RX_FLUSH_SHIFT 31
63 #define S_FIFO_TX_FLUSH_SHIFT 30
64 #define S_FIFO_RX_CNT_SHIFT 16
65 #define S_FIFO_RX_CNT_MASK 0x7f
66 #define S_FIFO_RX_THLD_SHIFT 8
67 #define S_FIFO_RX_THLD_MASK 0x3f
69 #define M_CMD_OFFSET 0x30
70 #define M_CMD_START_BUSY_SHIFT 31
71 #define M_CMD_STATUS_SHIFT 25
72 #define M_CMD_STATUS_MASK 0x07
73 #define M_CMD_STATUS_SUCCESS 0x0
74 #define M_CMD_STATUS_LOST_ARB 0x1
75 #define M_CMD_STATUS_NACK_ADDR 0x2
76 #define M_CMD_STATUS_NACK_DATA 0x3
77 #define M_CMD_STATUS_TIMEOUT 0x4
78 #define M_CMD_STATUS_FIFO_UNDERRUN 0x5
79 #define M_CMD_STATUS_RX_FIFO_FULL 0x6
80 #define M_CMD_PROTOCOL_SHIFT 9
81 #define M_CMD_PROTOCOL_MASK 0xf
82 #define M_CMD_PROTOCOL_BLK_WR 0x7
83 #define M_CMD_PROTOCOL_BLK_RD 0x8
84 #define M_CMD_PEC_SHIFT 8
85 #define M_CMD_RD_CNT_SHIFT 0
86 #define M_CMD_RD_CNT_MASK 0xff
88 #define S_CMD_OFFSET 0x34
89 #define S_CMD_START_BUSY_SHIFT 31
90 #define S_CMD_STATUS_SHIFT 23
91 #define S_CMD_STATUS_MASK 0x07
92 #define S_CMD_STATUS_SUCCESS 0x0
93 #define S_CMD_STATUS_TIMEOUT 0x5
95 #define IE_OFFSET 0x38
96 #define IE_M_RX_FIFO_FULL_SHIFT 31
97 #define IE_M_RX_THLD_SHIFT 30
98 #define IE_M_START_BUSY_SHIFT 28
99 #define IE_M_TX_UNDERRUN_SHIFT 27
100 #define IE_S_RX_FIFO_FULL_SHIFT 26
101 #define IE_S_RX_THLD_SHIFT 25
102 #define IE_S_RX_EVENT_SHIFT 24
103 #define IE_S_START_BUSY_SHIFT 23
104 #define IE_S_TX_UNDERRUN_SHIFT 22
105 #define IE_S_RD_EVENT_SHIFT 21
107 #define IS_OFFSET 0x3c
108 #define IS_M_RX_FIFO_FULL_SHIFT 31
109 #define IS_M_RX_THLD_SHIFT 30
110 #define IS_M_START_BUSY_SHIFT 28
111 #define IS_M_TX_UNDERRUN_SHIFT 27
112 #define IS_S_RX_FIFO_FULL_SHIFT 26
113 #define IS_S_RX_THLD_SHIFT 25
114 #define IS_S_RX_EVENT_SHIFT 24
115 #define IS_S_START_BUSY_SHIFT 23
116 #define IS_S_TX_UNDERRUN_SHIFT 22
117 #define IS_S_RD_EVENT_SHIFT 21
119 #define M_TX_OFFSET 0x40
120 #define M_TX_WR_STATUS_SHIFT 31
121 #define M_TX_DATA_SHIFT 0
122 #define M_TX_DATA_MASK 0xff
124 #define M_RX_OFFSET 0x44
125 #define M_RX_STATUS_SHIFT 30
126 #define M_RX_STATUS_MASK 0x03
127 #define M_RX_PEC_ERR_SHIFT 29
128 #define M_RX_DATA_SHIFT 0
129 #define M_RX_DATA_MASK 0xff
131 #define S_TX_OFFSET 0x48
132 #define S_TX_WR_STATUS_SHIFT 31
133 #define S_TX_DATA_SHIFT 0
134 #define S_TX_DATA_MASK 0xff
136 #define S_RX_OFFSET 0x4c
137 #define S_RX_STATUS_SHIFT 30
138 #define S_RX_STATUS_MASK 0x03
139 #define S_RX_PEC_ERR_SHIFT 29
140 #define S_RX_DATA_SHIFT 0
141 #define S_RX_DATA_MASK 0xff
143 #define I2C_TIMEOUT_MSEC 50000
144 #define M_TX_RX_FIFO_SIZE 64
145 #define M_RX_FIFO_MAX_THLD_VALUE (M_TX_RX_FIFO_SIZE - 1)
147 #define M_RX_MAX_READ_LEN 255
148 #define M_RX_FIFO_THLD_VALUE 50
150 #define IE_M_ALL_INTERRUPT_SHIFT 27
151 #define IE_M_ALL_INTERRUPT_MASK 0x1e
153 #define SLAVE_READ_WRITE_BIT_MASK 0x1
154 #define SLAVE_READ_WRITE_BIT_SHIFT 0x1
155 #define SLAVE_MAX_SIZE_TRANSACTION 64
156 #define SLAVE_CLOCK_STRETCH_TIME 25
158 #define IE_S_ALL_INTERRUPT_SHIFT 21
159 #define IE_S_ALL_INTERRUPT_MASK 0x3f
161 enum i2c_slave_read_status {
162 I2C_SLAVE_RX_FIFO_EMPTY = 0,
168 enum bus_speed_index {
173 enum bcm_iproc_i2c_type {
178 struct bcm_iproc_i2c_dev {
179 struct device *device;
180 enum bcm_iproc_i2c_type type;
184 void __iomem *idm_base;
188 /* lock for indirect access through IDM */
191 struct i2c_adapter adapter;
192 unsigned int bus_speed;
194 struct completion done;
199 struct i2c_client *slave;
201 /* bytes that have been transferred */
202 unsigned int tx_bytes;
203 /* bytes that have been read */
204 unsigned int rx_bytes;
205 unsigned int thld_bytes;
209 * Can be expanded in the future if more interrupt status bits are utilized
211 #define ISR_MASK (BIT(IS_M_START_BUSY_SHIFT) | BIT(IS_M_TX_UNDERRUN_SHIFT)\
212 | BIT(IS_M_RX_THLD_SHIFT))
214 #define ISR_MASK_SLAVE (BIT(IS_S_START_BUSY_SHIFT)\
215 | BIT(IS_S_RX_EVENT_SHIFT) | BIT(IS_S_RD_EVENT_SHIFT)\
216 | BIT(IS_S_TX_UNDERRUN_SHIFT))
218 static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave);
219 static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave);
220 static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,
223 static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
228 if (iproc_i2c->idm_base) {
229 spin_lock(&iproc_i2c->idm_lock);
230 writel(iproc_i2c->ape_addr_mask,
231 iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
232 val = readl(iproc_i2c->base + offset);
233 spin_unlock(&iproc_i2c->idm_lock);
235 val = readl(iproc_i2c->base + offset);
241 static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
244 if (iproc_i2c->idm_base) {
245 spin_lock(&iproc_i2c->idm_lock);
246 writel(iproc_i2c->ape_addr_mask,
247 iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
248 writel(val, iproc_i2c->base + offset);
249 spin_unlock(&iproc_i2c->idm_lock);
251 writel(val, iproc_i2c->base + offset);
255 static void bcm_iproc_i2c_slave_init(
256 struct bcm_iproc_i2c_dev *iproc_i2c, bool need_reset)
261 /* put controller in reset */
262 val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
263 val |= BIT(CFG_RESET_SHIFT);
264 iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
266 /* wait 100 usec per spec */
269 /* bring controller out of reset */
270 val &= ~(BIT(CFG_RESET_SHIFT));
271 iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
274 /* flush TX/RX FIFOs */
275 val = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));
276 iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val);
278 /* Maximum slave stretch time */
279 val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
280 val &= ~(TIM_RAND_SLAVE_STRETCH_MASK << TIM_RAND_SLAVE_STRETCH_SHIFT);
281 val |= (SLAVE_CLOCK_STRETCH_TIME << TIM_RAND_SLAVE_STRETCH_SHIFT);
282 iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
284 /* Configure the slave address */
285 val = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);
286 val |= BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);
287 val &= ~(S_CFG_NIC_SMB_ADDR3_MASK << S_CFG_NIC_SMB_ADDR3_SHIFT);
288 val |= (iproc_i2c->slave->addr << S_CFG_NIC_SMB_ADDR3_SHIFT);
289 iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, val);
291 /* clear all pending slave interrupts */
292 iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE);
294 /* Enable interrupt register to indicate a valid byte in receive fifo */
295 val = BIT(IE_S_RX_EVENT_SHIFT);
296 /* Enable interrupt register for the Slave BUSY command */
297 val |= BIT(IE_S_START_BUSY_SHIFT);
298 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
301 static void bcm_iproc_i2c_check_slave_status(
302 struct bcm_iproc_i2c_dev *iproc_i2c)
306 val = iproc_i2c_rd_reg(iproc_i2c, S_CMD_OFFSET);
307 /* status is valid only when START_BUSY is cleared after it was set */
308 if (val & BIT(S_CMD_START_BUSY_SHIFT))
311 val = (val >> S_CMD_STATUS_SHIFT) & S_CMD_STATUS_MASK;
312 if (val == S_CMD_STATUS_TIMEOUT) {
313 dev_err(iproc_i2c->device, "slave random stretch time timeout\n");
315 /* re-initialize i2c for recovery */
316 bcm_iproc_i2c_enable_disable(iproc_i2c, false);
317 bcm_iproc_i2c_slave_init(iproc_i2c, true);
318 bcm_iproc_i2c_enable_disable(iproc_i2c, true);
322 static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c,
328 /* Slave RX byte receive */
329 if (status & BIT(IS_S_RX_EVENT_SHIFT)) {
330 val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET);
331 rx_status = (val >> S_RX_STATUS_SHIFT) & S_RX_STATUS_MASK;
332 if (rx_status == I2C_SLAVE_RX_START) {
333 /* Start of SMBUS for Master write */
334 i2c_slave_event(iproc_i2c->slave,
335 I2C_SLAVE_WRITE_REQUESTED, &value);
337 val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET);
338 value = (u8)((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK);
339 i2c_slave_event(iproc_i2c->slave,
340 I2C_SLAVE_WRITE_RECEIVED, &value);
341 } else if (status & BIT(IS_S_RD_EVENT_SHIFT)) {
342 /* Start of SMBUS for Master Read */
343 i2c_slave_event(iproc_i2c->slave,
344 I2C_SLAVE_READ_REQUESTED, &value);
345 iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value);
347 val = BIT(S_CMD_START_BUSY_SHIFT);
348 iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);
351 * Enable interrupt for TX FIFO becomes empty and
352 * less than PKT_LENGTH bytes were output on the SMBUS
354 val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
355 val |= BIT(IE_S_TX_UNDERRUN_SHIFT);
356 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
358 /* Master write other than start */
359 value = (u8)((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK);
360 i2c_slave_event(iproc_i2c->slave,
361 I2C_SLAVE_WRITE_RECEIVED, &value);
363 } else if (status & BIT(IS_S_TX_UNDERRUN_SHIFT)) {
364 /* Master read other than start */
365 i2c_slave_event(iproc_i2c->slave,
366 I2C_SLAVE_READ_PROCESSED, &value);
368 iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value);
369 val = BIT(S_CMD_START_BUSY_SHIFT);
370 iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);
374 if (status & BIT(IS_S_START_BUSY_SHIFT)) {
375 i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP, &value);
377 * Enable interrupt for TX FIFO becomes empty and
378 * less than PKT_LENGTH bytes were output on the SMBUS
380 val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
381 val &= ~BIT(IE_S_TX_UNDERRUN_SHIFT);
382 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
385 /* clear interrupt status */
386 iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);
388 bcm_iproc_i2c_check_slave_status(iproc_i2c);
392 static void bcm_iproc_i2c_read_valid_bytes(struct bcm_iproc_i2c_dev *iproc_i2c)
394 struct i2c_msg *msg = iproc_i2c->msg;
397 /* Read valid data from RX FIFO */
398 while (iproc_i2c->rx_bytes < msg->len) {
399 val = iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET);
402 if (!((val >> M_RX_STATUS_SHIFT) & M_RX_STATUS_MASK))
405 msg->buf[iproc_i2c->rx_bytes] =
406 (val >> M_RX_DATA_SHIFT) & M_RX_DATA_MASK;
407 iproc_i2c->rx_bytes++;
411 static void bcm_iproc_i2c_send(struct bcm_iproc_i2c_dev *iproc_i2c)
413 struct i2c_msg *msg = iproc_i2c->msg;
414 unsigned int tx_bytes = msg->len - iproc_i2c->tx_bytes;
418 /* can only fill up to the FIFO size */
419 tx_bytes = min_t(unsigned int, tx_bytes, M_TX_RX_FIFO_SIZE);
420 for (i = 0; i < tx_bytes; i++) {
421 /* start from where we left over */
422 unsigned int idx = iproc_i2c->tx_bytes + i;
426 /* mark the last byte */
427 if (idx == msg->len - 1) {
428 val |= BIT(M_TX_WR_STATUS_SHIFT);
430 if (iproc_i2c->irq) {
434 * Since this is the last byte, we should now
435 * disable TX FIFO underrun interrupt
437 tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
438 tmp &= ~BIT(IE_M_TX_UNDERRUN_SHIFT);
439 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET,
444 /* load data into TX FIFO */
445 iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
448 /* update number of transferred bytes */
449 iproc_i2c->tx_bytes += tx_bytes;
452 static void bcm_iproc_i2c_read(struct bcm_iproc_i2c_dev *iproc_i2c)
454 struct i2c_msg *msg = iproc_i2c->msg;
457 bcm_iproc_i2c_read_valid_bytes(iproc_i2c);
458 bytes_left = msg->len - iproc_i2c->rx_bytes;
459 if (bytes_left == 0) {
460 if (iproc_i2c->irq) {
461 /* finished reading all data, disable rx thld event */
462 val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
463 val &= ~BIT(IS_M_RX_THLD_SHIFT);
464 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
466 } else if (bytes_left < iproc_i2c->thld_bytes) {
467 /* set bytes left as threshold */
468 val = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);
469 val &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);
470 val |= (bytes_left << M_FIFO_RX_THLD_SHIFT);
471 iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
472 iproc_i2c->thld_bytes = bytes_left;
475 * bytes_left >= iproc_i2c->thld_bytes,
476 * hence no need to change the THRESHOLD SET.
477 * It will remain as iproc_i2c->thld_bytes itself
481 static void bcm_iproc_i2c_process_m_event(struct bcm_iproc_i2c_dev *iproc_i2c,
484 /* TX FIFO is empty and we have more data to send */
485 if (status & BIT(IS_M_TX_UNDERRUN_SHIFT))
486 bcm_iproc_i2c_send(iproc_i2c);
488 /* RX FIFO threshold is reached and data needs to be read out */
489 if (status & BIT(IS_M_RX_THLD_SHIFT))
490 bcm_iproc_i2c_read(iproc_i2c);
492 /* transfer is done */
493 if (status & BIT(IS_M_START_BUSY_SHIFT)) {
494 iproc_i2c->xfer_is_done = 1;
496 complete(&iproc_i2c->done);
500 static irqreturn_t bcm_iproc_i2c_isr(int irq, void *data)
502 struct bcm_iproc_i2c_dev *iproc_i2c = data;
503 u32 status = iproc_i2c_rd_reg(iproc_i2c, IS_OFFSET);
505 u32 sl_status = status & ISR_MASK_SLAVE;
508 ret = bcm_iproc_i2c_slave_isr(iproc_i2c, sl_status);
519 /* process all master based events */
520 bcm_iproc_i2c_process_m_event(iproc_i2c, status);
521 iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);
526 static int bcm_iproc_i2c_init(struct bcm_iproc_i2c_dev *iproc_i2c)
530 /* put controller in reset */
531 val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
532 val |= BIT(CFG_RESET_SHIFT);
533 val &= ~(BIT(CFG_EN_SHIFT));
534 iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
536 /* wait 100 usec per spec */
539 /* bring controller out of reset */
540 val &= ~(BIT(CFG_RESET_SHIFT));
541 iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
543 /* flush TX/RX FIFOs and set RX FIFO threshold to zero */
544 val = (BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT));
545 iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
546 /* disable all interrupts */
547 val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
548 val &= ~(IE_M_ALL_INTERRUPT_MASK <<
549 IE_M_ALL_INTERRUPT_SHIFT);
550 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
552 /* clear all pending interrupts */
553 iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, 0xffffffff);
558 static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,
563 val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
565 val |= BIT(CFG_EN_SHIFT);
567 val &= ~BIT(CFG_EN_SHIFT);
568 iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
571 static int bcm_iproc_i2c_check_status(struct bcm_iproc_i2c_dev *iproc_i2c,
576 val = iproc_i2c_rd_reg(iproc_i2c, M_CMD_OFFSET);
577 val = (val >> M_CMD_STATUS_SHIFT) & M_CMD_STATUS_MASK;
580 case M_CMD_STATUS_SUCCESS:
583 case M_CMD_STATUS_LOST_ARB:
584 dev_dbg(iproc_i2c->device, "lost bus arbitration\n");
587 case M_CMD_STATUS_NACK_ADDR:
588 dev_dbg(iproc_i2c->device, "NAK addr:0x%02x\n", msg->addr);
591 case M_CMD_STATUS_NACK_DATA:
592 dev_dbg(iproc_i2c->device, "NAK data\n");
595 case M_CMD_STATUS_TIMEOUT:
596 dev_dbg(iproc_i2c->device, "bus timeout\n");
599 case M_CMD_STATUS_FIFO_UNDERRUN:
600 dev_dbg(iproc_i2c->device, "FIFO under-run\n");
603 case M_CMD_STATUS_RX_FIFO_FULL:
604 dev_dbg(iproc_i2c->device, "RX FIFO full\n");
608 dev_dbg(iproc_i2c->device, "unknown error code=%d\n", val);
610 /* re-initialize i2c for recovery */
611 bcm_iproc_i2c_enable_disable(iproc_i2c, false);
612 bcm_iproc_i2c_init(iproc_i2c);
613 bcm_iproc_i2c_enable_disable(iproc_i2c, true);
619 static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,
623 unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT_MSEC);
627 iproc_i2c_wr_reg(iproc_i2c, M_CMD_OFFSET, cmd);
629 if (iproc_i2c->irq) {
630 time_left = wait_for_completion_timeout(&iproc_i2c->done,
632 /* disable all interrupts */
633 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
634 /* read it back to flush the write */
635 iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
636 /* make sure the interrupt handler isn't running */
637 synchronize_irq(iproc_i2c->irq);
639 } else { /* polling mode */
640 unsigned long timeout = jiffies + time_left;
643 status = iproc_i2c_rd_reg(iproc_i2c,
644 IS_OFFSET) & ISR_MASK;
645 bcm_iproc_i2c_process_m_event(iproc_i2c, status);
646 iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);
648 if (time_after(jiffies, timeout)) {
655 } while (!iproc_i2c->xfer_is_done);
658 if (!time_left && !iproc_i2c->xfer_is_done) {
659 dev_err(iproc_i2c->device, "transaction timed out\n");
661 /* flush both TX/RX FIFOs */
662 val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
663 iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
667 ret = bcm_iproc_i2c_check_status(iproc_i2c, msg);
669 /* flush both TX/RX FIFOs */
670 val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
671 iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
678 static int bcm_iproc_i2c_xfer_single_msg(struct bcm_iproc_i2c_dev *iproc_i2c,
683 u32 val, tmp, val_intr_en;
684 unsigned int tx_bytes;
686 /* check if bus is busy */
687 if (!!(iproc_i2c_rd_reg(iproc_i2c,
688 M_CMD_OFFSET) & BIT(M_CMD_START_BUSY_SHIFT))) {
689 dev_warn(iproc_i2c->device, "bus is busy\n");
693 iproc_i2c->msg = msg;
695 /* format and load slave address into the TX FIFO */
696 addr = i2c_8bit_addr_from_msg(msg);
697 iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, addr);
700 * For a write transaction, load data into the TX FIFO. Only allow
701 * loading up to TX FIFO size - 1 bytes of data since the first byte
702 * has been used up by the slave address
704 tx_bytes = min_t(unsigned int, msg->len, M_TX_RX_FIFO_SIZE - 1);
705 if (!(msg->flags & I2C_M_RD)) {
706 for (i = 0; i < tx_bytes; i++) {
709 /* mark the last byte */
710 if (i == msg->len - 1)
711 val |= BIT(M_TX_WR_STATUS_SHIFT);
713 iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
715 iproc_i2c->tx_bytes = tx_bytes;
718 /* mark as incomplete before starting the transaction */
720 reinit_completion(&iproc_i2c->done);
722 iproc_i2c->xfer_is_done = 0;
725 * Enable the "start busy" interrupt, which will be triggered after the
726 * transaction is done, i.e., the internal start_busy bit, transitions
729 val_intr_en = BIT(IE_M_START_BUSY_SHIFT);
732 * If TX data size is larger than the TX FIFO, need to enable TX
733 * underrun interrupt, which will be triggerred when the TX FIFO is
734 * empty. When that happens we can then pump more data into the FIFO
736 if (!(msg->flags & I2C_M_RD) &&
737 msg->len > iproc_i2c->tx_bytes)
738 val_intr_en |= BIT(IE_M_TX_UNDERRUN_SHIFT);
741 * Now we can activate the transfer. For a read operation, specify the
742 * number of bytes to read
744 val = BIT(M_CMD_START_BUSY_SHIFT);
745 if (msg->flags & I2C_M_RD) {
746 iproc_i2c->rx_bytes = 0;
747 if (msg->len > M_RX_FIFO_MAX_THLD_VALUE)
748 iproc_i2c->thld_bytes = M_RX_FIFO_THLD_VALUE;
750 iproc_i2c->thld_bytes = msg->len;
752 /* set threshold value */
753 tmp = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);
754 tmp &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);
755 tmp |= iproc_i2c->thld_bytes << M_FIFO_RX_THLD_SHIFT;
756 iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, tmp);
758 /* enable the RX threshold interrupt */
759 val_intr_en |= BIT(IE_M_RX_THLD_SHIFT);
761 val |= (M_CMD_PROTOCOL_BLK_RD << M_CMD_PROTOCOL_SHIFT) |
762 (msg->len << M_CMD_RD_CNT_SHIFT);
764 val |= (M_CMD_PROTOCOL_BLK_WR << M_CMD_PROTOCOL_SHIFT);
768 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val_intr_en);
770 return bcm_iproc_i2c_xfer_wait(iproc_i2c, msg, val);
773 static int bcm_iproc_i2c_xfer(struct i2c_adapter *adapter,
774 struct i2c_msg msgs[], int num)
776 struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adapter);
779 /* go through all messages */
780 for (i = 0; i < num; i++) {
781 ret = bcm_iproc_i2c_xfer_single_msg(iproc_i2c, &msgs[i]);
783 dev_dbg(iproc_i2c->device, "xfer failed\n");
791 static uint32_t bcm_iproc_i2c_functionality(struct i2c_adapter *adap)
795 /* We do not support the SMBUS Quick command */
796 val = I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
798 if (adap->algo->reg_slave)
799 val |= I2C_FUNC_SLAVE;
804 static struct i2c_algorithm bcm_iproc_algo = {
805 .master_xfer = bcm_iproc_i2c_xfer,
806 .functionality = bcm_iproc_i2c_functionality,
807 .reg_slave = bcm_iproc_i2c_reg_slave,
808 .unreg_slave = bcm_iproc_i2c_unreg_slave,
811 static struct i2c_adapter_quirks bcm_iproc_i2c_quirks = {
812 .max_read_len = M_RX_MAX_READ_LEN,
815 static int bcm_iproc_i2c_cfg_speed(struct bcm_iproc_i2c_dev *iproc_i2c)
817 unsigned int bus_speed;
819 int ret = of_property_read_u32(iproc_i2c->device->of_node,
820 "clock-frequency", &bus_speed);
822 dev_info(iproc_i2c->device,
823 "unable to interpret clock-frequency DT property\n");
827 if (bus_speed < 100000) {
828 dev_err(iproc_i2c->device, "%d Hz bus speed not supported\n",
830 dev_err(iproc_i2c->device,
831 "valid speeds are 100khz and 400khz\n");
833 } else if (bus_speed < 400000) {
839 iproc_i2c->bus_speed = bus_speed;
840 val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
841 val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
842 val |= (bus_speed == 400000) << TIM_CFG_MODE_400_SHIFT;
843 iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
845 dev_info(iproc_i2c->device, "bus set to %u Hz\n", bus_speed);
850 static int bcm_iproc_i2c_probe(struct platform_device *pdev)
853 struct bcm_iproc_i2c_dev *iproc_i2c;
854 struct i2c_adapter *adap;
855 struct resource *res;
857 iproc_i2c = devm_kzalloc(&pdev->dev, sizeof(*iproc_i2c),
862 platform_set_drvdata(pdev, iproc_i2c);
863 iproc_i2c->device = &pdev->dev;
865 (enum bcm_iproc_i2c_type)of_device_get_match_data(&pdev->dev);
866 init_completion(&iproc_i2c->done);
868 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
869 iproc_i2c->base = devm_ioremap_resource(iproc_i2c->device, res);
870 if (IS_ERR(iproc_i2c->base))
871 return PTR_ERR(iproc_i2c->base);
873 if (iproc_i2c->type == IPROC_I2C_NIC) {
874 res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
875 iproc_i2c->idm_base = devm_ioremap_resource(iproc_i2c->device,
877 if (IS_ERR(iproc_i2c->idm_base))
878 return PTR_ERR(iproc_i2c->idm_base);
880 ret = of_property_read_u32(iproc_i2c->device->of_node,
881 "brcm,ape-hsls-addr-mask",
882 &iproc_i2c->ape_addr_mask);
884 dev_err(iproc_i2c->device,
885 "'brcm,ape-hsls-addr-mask' missing\n");
889 spin_lock_init(&iproc_i2c->idm_lock);
891 /* no slave support */
892 bcm_iproc_algo.reg_slave = NULL;
893 bcm_iproc_algo.unreg_slave = NULL;
896 ret = bcm_iproc_i2c_init(iproc_i2c);
900 ret = bcm_iproc_i2c_cfg_speed(iproc_i2c);
904 irq = platform_get_irq(pdev, 0);
906 ret = devm_request_irq(iproc_i2c->device, irq,
907 bcm_iproc_i2c_isr, 0, pdev->name,
910 dev_err(iproc_i2c->device,
911 "unable to request irq %i\n", irq);
915 iproc_i2c->irq = irq;
917 dev_warn(iproc_i2c->device,
918 "no irq resource, falling back to poll mode\n");
921 bcm_iproc_i2c_enable_disable(iproc_i2c, true);
923 adap = &iproc_i2c->adapter;
924 i2c_set_adapdata(adap, iproc_i2c);
925 strlcpy(adap->name, "Broadcom iProc I2C adapter", sizeof(adap->name));
926 adap->algo = &bcm_iproc_algo;
927 adap->quirks = &bcm_iproc_i2c_quirks;
928 adap->dev.parent = &pdev->dev;
929 adap->dev.of_node = pdev->dev.of_node;
931 return i2c_add_adapter(adap);
934 static int bcm_iproc_i2c_remove(struct platform_device *pdev)
936 struct bcm_iproc_i2c_dev *iproc_i2c = platform_get_drvdata(pdev);
938 if (iproc_i2c->irq) {
940 * Make sure there's no pending interrupt when we remove the
943 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
944 iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
945 synchronize_irq(iproc_i2c->irq);
948 i2c_del_adapter(&iproc_i2c->adapter);
949 bcm_iproc_i2c_enable_disable(iproc_i2c, false);
954 #ifdef CONFIG_PM_SLEEP
956 static int bcm_iproc_i2c_suspend(struct device *dev)
958 struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
960 if (iproc_i2c->irq) {
962 * Make sure there's no pending interrupt when we go into
965 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
966 iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
967 synchronize_irq(iproc_i2c->irq);
970 /* now disable the controller */
971 bcm_iproc_i2c_enable_disable(iproc_i2c, false);
976 static int bcm_iproc_i2c_resume(struct device *dev)
978 struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
983 * Power domain could have been shut off completely in system deep
984 * sleep, so re-initialize the block here
986 ret = bcm_iproc_i2c_init(iproc_i2c);
990 /* configure to the desired bus speed */
991 val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
992 val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
993 val |= (iproc_i2c->bus_speed == 400000) << TIM_CFG_MODE_400_SHIFT;
994 iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
996 bcm_iproc_i2c_enable_disable(iproc_i2c, true);
1001 static const struct dev_pm_ops bcm_iproc_i2c_pm_ops = {
1002 .suspend_late = &bcm_iproc_i2c_suspend,
1003 .resume_early = &bcm_iproc_i2c_resume
1006 #define BCM_IPROC_I2C_PM_OPS (&bcm_iproc_i2c_pm_ops)
1008 #define BCM_IPROC_I2C_PM_OPS NULL
1009 #endif /* CONFIG_PM_SLEEP */
1012 static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave)
1014 struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);
1016 if (iproc_i2c->slave)
1019 if (slave->flags & I2C_CLIENT_TEN)
1020 return -EAFNOSUPPORT;
1022 iproc_i2c->slave = slave;
1023 bcm_iproc_i2c_slave_init(iproc_i2c, false);
1027 static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave)
1030 struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);
1032 if (!iproc_i2c->slave)
1035 iproc_i2c->slave = NULL;
1037 /* disable all slave interrupts */
1038 tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
1039 tmp &= ~(IE_S_ALL_INTERRUPT_MASK <<
1040 IE_S_ALL_INTERRUPT_SHIFT);
1041 iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, tmp);
1043 /* Erase the slave address programmed */
1044 tmp = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);
1045 tmp &= ~BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);
1046 iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, tmp);
1051 static const struct of_device_id bcm_iproc_i2c_of_match[] = {
1053 .compatible = "brcm,iproc-i2c",
1054 .data = (int *)IPROC_I2C,
1056 .compatible = "brcm,iproc-nic-i2c",
1057 .data = (int *)IPROC_I2C_NIC,
1061 MODULE_DEVICE_TABLE(of, bcm_iproc_i2c_of_match);
1063 static struct platform_driver bcm_iproc_i2c_driver = {
1065 .name = "bcm-iproc-i2c",
1066 .of_match_table = bcm_iproc_i2c_of_match,
1067 .pm = BCM_IPROC_I2C_PM_OPS,
1069 .probe = bcm_iproc_i2c_probe,
1070 .remove = bcm_iproc_i2c_remove,
1072 module_platform_driver(bcm_iproc_i2c_driver);
1074 MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>");
1075 MODULE_DESCRIPTION("Broadcom iProc I2C Driver");
1076 MODULE_LICENSE("GPL v2");