2 * drivers/i2c/busses/i2c-tegra.c
4 * Copyright (C) 2010 Google, Inc.
5 * Author: Colin Cross <ccross@android.com>
7 * This software is licensed under the terms of the GNU General Public
8 * License version 2, as published by the Free Software Foundation, and
9 * may be copied, distributed, and modified under those terms.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
18 #include <linux/kernel.h>
19 #include <linux/init.h>
20 #include <linux/platform_device.h>
21 #include <linux/clk.h>
22 #include <linux/err.h>
23 #include <linux/i2c.h>
25 #include <linux/interrupt.h>
26 #include <linux/delay.h>
27 #include <linux/slab.h>
28 #include <linux/i2c-tegra.h>
29 #include <linux/of_i2c.h>
30 #include <linux/of_device.h>
31 #include <linux/module.h>
33 #include <asm/unaligned.h>
37 #define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000))
38 #define BYTES_PER_FIFO_WORD 4
40 #define I2C_CNFG 0x000
41 #define I2C_CNFG_DEBOUNCE_CNT_SHIFT 12
42 #define I2C_CNFG_PACKET_MODE_EN (1<<10)
43 #define I2C_CNFG_NEW_MASTER_FSM (1<<11)
44 #define I2C_STATUS 0x01C
45 #define I2C_SL_CNFG 0x020
46 #define I2C_SL_CNFG_NACK (1<<1)
47 #define I2C_SL_CNFG_NEWSL (1<<2)
48 #define I2C_SL_ADDR1 0x02c
49 #define I2C_SL_ADDR2 0x030
50 #define I2C_TX_FIFO 0x050
51 #define I2C_RX_FIFO 0x054
52 #define I2C_PACKET_TRANSFER_STATUS 0x058
53 #define I2C_FIFO_CONTROL 0x05c
54 #define I2C_FIFO_CONTROL_TX_FLUSH (1<<1)
55 #define I2C_FIFO_CONTROL_RX_FLUSH (1<<0)
56 #define I2C_FIFO_CONTROL_TX_TRIG_SHIFT 5
57 #define I2C_FIFO_CONTROL_RX_TRIG_SHIFT 2
58 #define I2C_FIFO_STATUS 0x060
59 #define I2C_FIFO_STATUS_TX_MASK 0xF0
60 #define I2C_FIFO_STATUS_TX_SHIFT 4
61 #define I2C_FIFO_STATUS_RX_MASK 0x0F
62 #define I2C_FIFO_STATUS_RX_SHIFT 0
63 #define I2C_INT_MASK 0x064
64 #define I2C_INT_STATUS 0x068
65 #define I2C_INT_PACKET_XFER_COMPLETE (1<<7)
66 #define I2C_INT_ALL_PACKETS_XFER_COMPLETE (1<<6)
67 #define I2C_INT_TX_FIFO_OVERFLOW (1<<5)
68 #define I2C_INT_RX_FIFO_UNDERFLOW (1<<4)
69 #define I2C_INT_NO_ACK (1<<3)
70 #define I2C_INT_ARBITRATION_LOST (1<<2)
71 #define I2C_INT_TX_FIFO_DATA_REQ (1<<1)
72 #define I2C_INT_RX_FIFO_DATA_REQ (1<<0)
73 #define I2C_CLK_DIVISOR 0x06c
75 #define DVC_CTRL_REG1 0x000
76 #define DVC_CTRL_REG1_INTR_EN (1<<10)
77 #define DVC_CTRL_REG2 0x004
78 #define DVC_CTRL_REG3 0x008
79 #define DVC_CTRL_REG3_SW_PROG (1<<26)
80 #define DVC_CTRL_REG3_I2C_DONE_INTR_EN (1<<30)
81 #define DVC_STATUS 0x00c
82 #define DVC_STATUS_I2C_DONE_INTR (1<<30)
84 #define I2C_ERR_NONE 0x00
85 #define I2C_ERR_NO_ACK 0x01
86 #define I2C_ERR_ARBITRATION_LOST 0x02
87 #define I2C_ERR_UNKNOWN_INTERRUPT 0x04
89 #define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
90 #define PACKET_HEADER0_PACKET_ID_SHIFT 16
91 #define PACKET_HEADER0_CONT_ID_SHIFT 12
92 #define PACKET_HEADER0_PROTOCOL_I2C (1<<4)
94 #define I2C_HEADER_HIGHSPEED_MODE (1<<22)
95 #define I2C_HEADER_CONT_ON_NAK (1<<21)
96 #define I2C_HEADER_SEND_START_BYTE (1<<20)
97 #define I2C_HEADER_READ (1<<19)
98 #define I2C_HEADER_10BIT_ADDR (1<<18)
99 #define I2C_HEADER_IE_ENABLE (1<<17)
100 #define I2C_HEADER_REPEAT_START (1<<16)
101 #define I2C_HEADER_CONTINUE_XFER (1<<15)
102 #define I2C_HEADER_MASTER_ADDR_SHIFT 12
103 #define I2C_HEADER_SLAVE_ADDR_SHIFT 1
105 * msg_end_type: The bus control which need to be send at end of transfer.
106 * @MSG_END_STOP: Send stop pulse at end of transfer.
107 * @MSG_END_REPEAT_START: Send repeat start at end of transfer.
108 * @MSG_END_CONTINUE: The following on message is coming and so do not send
109 * stop or repeat start.
113 MSG_END_REPEAT_START
,
118 * struct tegra_i2c_hw_feature : Different HW support on Tegra
119 * @has_continue_xfer_support: Continue transfer supports.
122 struct tegra_i2c_hw_feature
{
123 bool has_continue_xfer_support
;
127 * struct tegra_i2c_dev - per device i2c context
128 * @dev: device reference for power management
129 * @hw: Tegra i2c hw feature.
130 * @adapter: core i2c layer adapter information
131 * @div_clk: clock reference for div clock of i2c controller.
132 * @fast_clk: clock reference for fast clock of i2c controller.
133 * @base: ioremapped registers cookie
134 * @cont_id: i2c controller id, used for for packet header
135 * @irq: irq number of transfer complete interrupt
136 * @is_dvc: identifies the DVC i2c controller, has a different register layout
137 * @msg_complete: transfer completion notifier
138 * @msg_err: error code for completed message
139 * @msg_buf: pointer to current message data
140 * @msg_buf_remaining: size of unsent data in the message buffer
141 * @msg_read: identifies read transfers
142 * @bus_clk_rate: current i2c bus clock rate
143 * @is_suspended: prevents i2c controller accesses after suspend is called
145 struct tegra_i2c_dev
{
147 const struct tegra_i2c_hw_feature
*hw
;
148 struct i2c_adapter adapter
;
150 struct clk
*fast_clk
;
156 struct completion msg_complete
;
159 size_t msg_buf_remaining
;
161 unsigned long bus_clk_rate
;
165 static void dvc_writel(struct tegra_i2c_dev
*i2c_dev
, u32 val
, unsigned long reg
)
167 writel(val
, i2c_dev
->base
+ reg
);
170 static u32
dvc_readl(struct tegra_i2c_dev
*i2c_dev
, unsigned long reg
)
172 return readl(i2c_dev
->base
+ reg
);
176 * i2c_writel and i2c_readl will offset the register if necessary to talk
177 * to the I2C block inside the DVC block
179 static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev
*i2c_dev
,
183 reg
+= (reg
>= I2C_TX_FIFO
) ? 0x10 : 0x40;
187 static void i2c_writel(struct tegra_i2c_dev
*i2c_dev
, u32 val
,
190 writel(val
, i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
));
192 /* Read back register to make sure that register writes completed */
193 if (reg
!= I2C_TX_FIFO
)
194 readl(i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
));
197 static u32
i2c_readl(struct tegra_i2c_dev
*i2c_dev
, unsigned long reg
)
199 return readl(i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
));
202 static void i2c_writesl(struct tegra_i2c_dev
*i2c_dev
, void *data
,
203 unsigned long reg
, int len
)
205 writesl(i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
), data
, len
);
208 static void i2c_readsl(struct tegra_i2c_dev
*i2c_dev
, void *data
,
209 unsigned long reg
, int len
)
211 readsl(i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
), data
, len
);
214 static void tegra_i2c_mask_irq(struct tegra_i2c_dev
*i2c_dev
, u32 mask
)
216 u32 int_mask
= i2c_readl(i2c_dev
, I2C_INT_MASK
);
218 i2c_writel(i2c_dev
, int_mask
, I2C_INT_MASK
);
221 static void tegra_i2c_unmask_irq(struct tegra_i2c_dev
*i2c_dev
, u32 mask
)
223 u32 int_mask
= i2c_readl(i2c_dev
, I2C_INT_MASK
);
225 i2c_writel(i2c_dev
, int_mask
, I2C_INT_MASK
);
228 static int tegra_i2c_flush_fifos(struct tegra_i2c_dev
*i2c_dev
)
230 unsigned long timeout
= jiffies
+ HZ
;
231 u32 val
= i2c_readl(i2c_dev
, I2C_FIFO_CONTROL
);
232 val
|= I2C_FIFO_CONTROL_TX_FLUSH
| I2C_FIFO_CONTROL_RX_FLUSH
;
233 i2c_writel(i2c_dev
, val
, I2C_FIFO_CONTROL
);
235 while (i2c_readl(i2c_dev
, I2C_FIFO_CONTROL
) &
236 (I2C_FIFO_CONTROL_TX_FLUSH
| I2C_FIFO_CONTROL_RX_FLUSH
)) {
237 if (time_after(jiffies
, timeout
)) {
238 dev_warn(i2c_dev
->dev
, "timeout waiting for fifo flush\n");
246 static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev
*i2c_dev
)
250 u8
*buf
= i2c_dev
->msg_buf
;
251 size_t buf_remaining
= i2c_dev
->msg_buf_remaining
;
252 int words_to_transfer
;
254 val
= i2c_readl(i2c_dev
, I2C_FIFO_STATUS
);
255 rx_fifo_avail
= (val
& I2C_FIFO_STATUS_RX_MASK
) >>
256 I2C_FIFO_STATUS_RX_SHIFT
;
258 /* Rounds down to not include partial word at the end of buf */
259 words_to_transfer
= buf_remaining
/ BYTES_PER_FIFO_WORD
;
260 if (words_to_transfer
> rx_fifo_avail
)
261 words_to_transfer
= rx_fifo_avail
;
263 i2c_readsl(i2c_dev
, buf
, I2C_RX_FIFO
, words_to_transfer
);
265 buf
+= words_to_transfer
* BYTES_PER_FIFO_WORD
;
266 buf_remaining
-= words_to_transfer
* BYTES_PER_FIFO_WORD
;
267 rx_fifo_avail
-= words_to_transfer
;
270 * If there is a partial word at the end of buf, handle it manually to
271 * prevent overwriting past the end of buf
273 if (rx_fifo_avail
> 0 && buf_remaining
> 0) {
274 BUG_ON(buf_remaining
> 3);
275 val
= i2c_readl(i2c_dev
, I2C_RX_FIFO
);
276 memcpy(buf
, &val
, buf_remaining
);
281 BUG_ON(rx_fifo_avail
> 0 && buf_remaining
> 0);
282 i2c_dev
->msg_buf_remaining
= buf_remaining
;
283 i2c_dev
->msg_buf
= buf
;
287 static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev
*i2c_dev
)
291 u8
*buf
= i2c_dev
->msg_buf
;
292 size_t buf_remaining
= i2c_dev
->msg_buf_remaining
;
293 int words_to_transfer
;
295 val
= i2c_readl(i2c_dev
, I2C_FIFO_STATUS
);
296 tx_fifo_avail
= (val
& I2C_FIFO_STATUS_TX_MASK
) >>
297 I2C_FIFO_STATUS_TX_SHIFT
;
299 /* Rounds down to not include partial word at the end of buf */
300 words_to_transfer
= buf_remaining
/ BYTES_PER_FIFO_WORD
;
302 /* It's very common to have < 4 bytes, so optimize that case. */
303 if (words_to_transfer
) {
304 if (words_to_transfer
> tx_fifo_avail
)
305 words_to_transfer
= tx_fifo_avail
;
308 * Update state before writing to FIFO. If this casues us
309 * to finish writing all bytes (AKA buf_remaining goes to 0) we
310 * have a potential for an interrupt (PACKET_XFER_COMPLETE is
311 * not maskable). We need to make sure that the isr sees
312 * buf_remaining as 0 and doesn't call us back re-entrantly.
314 buf_remaining
-= words_to_transfer
* BYTES_PER_FIFO_WORD
;
315 tx_fifo_avail
-= words_to_transfer
;
316 i2c_dev
->msg_buf_remaining
= buf_remaining
;
317 i2c_dev
->msg_buf
= buf
+
318 words_to_transfer
* BYTES_PER_FIFO_WORD
;
321 i2c_writesl(i2c_dev
, buf
, I2C_TX_FIFO
, words_to_transfer
);
323 buf
+= words_to_transfer
* BYTES_PER_FIFO_WORD
;
327 * If there is a partial word at the end of buf, handle it manually to
328 * prevent reading past the end of buf, which could cross a page
329 * boundary and fault.
331 if (tx_fifo_avail
> 0 && buf_remaining
> 0) {
332 BUG_ON(buf_remaining
> 3);
333 memcpy(&val
, buf
, buf_remaining
);
335 /* Again update before writing to FIFO to make sure isr sees. */
336 i2c_dev
->msg_buf_remaining
= 0;
337 i2c_dev
->msg_buf
= NULL
;
340 i2c_writel(i2c_dev
, val
, I2C_TX_FIFO
);
347 * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller)
348 * block. This block is identical to the rest of the I2C blocks, except that
349 * it only supports master mode, it has registers moved around, and it needs
350 * some extra init to get it into I2C mode. The register moves are handled
351 * by i2c_readl and i2c_writel
353 static void tegra_dvc_init(struct tegra_i2c_dev
*i2c_dev
)
356 val
= dvc_readl(i2c_dev
, DVC_CTRL_REG3
);
357 val
|= DVC_CTRL_REG3_SW_PROG
;
358 val
|= DVC_CTRL_REG3_I2C_DONE_INTR_EN
;
359 dvc_writel(i2c_dev
, val
, DVC_CTRL_REG3
);
361 val
= dvc_readl(i2c_dev
, DVC_CTRL_REG1
);
362 val
|= DVC_CTRL_REG1_INTR_EN
;
363 dvc_writel(i2c_dev
, val
, DVC_CTRL_REG1
);
366 static inline int tegra_i2c_clock_enable(struct tegra_i2c_dev
*i2c_dev
)
369 ret
= clk_prepare_enable(i2c_dev
->fast_clk
);
371 dev_err(i2c_dev
->dev
,
372 "Enabling fast clk failed, err %d\n", ret
);
375 ret
= clk_prepare_enable(i2c_dev
->div_clk
);
377 dev_err(i2c_dev
->dev
,
378 "Enabling div clk failed, err %d\n", ret
);
379 clk_disable_unprepare(i2c_dev
->fast_clk
);
384 static inline void tegra_i2c_clock_disable(struct tegra_i2c_dev
*i2c_dev
)
386 clk_disable_unprepare(i2c_dev
->div_clk
);
387 clk_disable_unprepare(i2c_dev
->fast_clk
);
390 static int tegra_i2c_init(struct tegra_i2c_dev
*i2c_dev
)
395 tegra_i2c_clock_enable(i2c_dev
);
397 tegra_periph_reset_assert(i2c_dev
->div_clk
);
399 tegra_periph_reset_deassert(i2c_dev
->div_clk
);
402 tegra_dvc_init(i2c_dev
);
404 val
= I2C_CNFG_NEW_MASTER_FSM
| I2C_CNFG_PACKET_MODE_EN
|
405 (0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT
);
406 i2c_writel(i2c_dev
, val
, I2C_CNFG
);
407 i2c_writel(i2c_dev
, 0, I2C_INT_MASK
);
408 clk_set_rate(i2c_dev
->div_clk
, i2c_dev
->bus_clk_rate
* 8);
410 if (!i2c_dev
->is_dvc
) {
411 u32 sl_cfg
= i2c_readl(i2c_dev
, I2C_SL_CNFG
);
412 sl_cfg
|= I2C_SL_CNFG_NACK
| I2C_SL_CNFG_NEWSL
;
413 i2c_writel(i2c_dev
, sl_cfg
, I2C_SL_CNFG
);
414 i2c_writel(i2c_dev
, 0xfc, I2C_SL_ADDR1
);
415 i2c_writel(i2c_dev
, 0x00, I2C_SL_ADDR2
);
419 val
= 7 << I2C_FIFO_CONTROL_TX_TRIG_SHIFT
|
420 0 << I2C_FIFO_CONTROL_RX_TRIG_SHIFT
;
421 i2c_writel(i2c_dev
, val
, I2C_FIFO_CONTROL
);
423 if (tegra_i2c_flush_fifos(i2c_dev
))
426 tegra_i2c_clock_disable(i2c_dev
);
428 if (i2c_dev
->irq_disabled
) {
429 i2c_dev
->irq_disabled
= 0;
430 enable_irq(i2c_dev
->irq
);
436 static irqreturn_t
tegra_i2c_isr(int irq
, void *dev_id
)
439 const u32 status_err
= I2C_INT_NO_ACK
| I2C_INT_ARBITRATION_LOST
;
440 struct tegra_i2c_dev
*i2c_dev
= dev_id
;
442 status
= i2c_readl(i2c_dev
, I2C_INT_STATUS
);
445 dev_warn(i2c_dev
->dev
, "irq status 0 %08x %08x %08x\n",
446 i2c_readl(i2c_dev
, I2C_PACKET_TRANSFER_STATUS
),
447 i2c_readl(i2c_dev
, I2C_STATUS
),
448 i2c_readl(i2c_dev
, I2C_CNFG
));
449 i2c_dev
->msg_err
|= I2C_ERR_UNKNOWN_INTERRUPT
;
451 if (!i2c_dev
->irq_disabled
) {
452 disable_irq_nosync(i2c_dev
->irq
);
453 i2c_dev
->irq_disabled
= 1;
458 if (unlikely(status
& status_err
)) {
459 if (status
& I2C_INT_NO_ACK
)
460 i2c_dev
->msg_err
|= I2C_ERR_NO_ACK
;
461 if (status
& I2C_INT_ARBITRATION_LOST
)
462 i2c_dev
->msg_err
|= I2C_ERR_ARBITRATION_LOST
;
466 if (i2c_dev
->msg_read
&& (status
& I2C_INT_RX_FIFO_DATA_REQ
)) {
467 if (i2c_dev
->msg_buf_remaining
)
468 tegra_i2c_empty_rx_fifo(i2c_dev
);
473 if (!i2c_dev
->msg_read
&& (status
& I2C_INT_TX_FIFO_DATA_REQ
)) {
474 if (i2c_dev
->msg_buf_remaining
)
475 tegra_i2c_fill_tx_fifo(i2c_dev
);
477 tegra_i2c_mask_irq(i2c_dev
, I2C_INT_TX_FIFO_DATA_REQ
);
480 i2c_writel(i2c_dev
, status
, I2C_INT_STATUS
);
482 dvc_writel(i2c_dev
, DVC_STATUS_I2C_DONE_INTR
, DVC_STATUS
);
484 if (status
& I2C_INT_PACKET_XFER_COMPLETE
) {
485 BUG_ON(i2c_dev
->msg_buf_remaining
);
486 complete(&i2c_dev
->msg_complete
);
490 /* An error occurred, mask all interrupts */
491 tegra_i2c_mask_irq(i2c_dev
, I2C_INT_NO_ACK
| I2C_INT_ARBITRATION_LOST
|
492 I2C_INT_PACKET_XFER_COMPLETE
| I2C_INT_TX_FIFO_DATA_REQ
|
493 I2C_INT_RX_FIFO_DATA_REQ
);
494 i2c_writel(i2c_dev
, status
, I2C_INT_STATUS
);
496 dvc_writel(i2c_dev
, DVC_STATUS_I2C_DONE_INTR
, DVC_STATUS
);
498 complete(&i2c_dev
->msg_complete
);
502 static int tegra_i2c_xfer_msg(struct tegra_i2c_dev
*i2c_dev
,
503 struct i2c_msg
*msg
, enum msg_end_type end_state
)
509 tegra_i2c_flush_fifos(i2c_dev
);
514 i2c_dev
->msg_buf
= msg
->buf
;
515 i2c_dev
->msg_buf_remaining
= msg
->len
;
516 i2c_dev
->msg_err
= I2C_ERR_NONE
;
517 i2c_dev
->msg_read
= (msg
->flags
& I2C_M_RD
);
518 INIT_COMPLETION(i2c_dev
->msg_complete
);
520 packet_header
= (0 << PACKET_HEADER0_HEADER_SIZE_SHIFT
) |
521 PACKET_HEADER0_PROTOCOL_I2C
|
522 (i2c_dev
->cont_id
<< PACKET_HEADER0_CONT_ID_SHIFT
) |
523 (1 << PACKET_HEADER0_PACKET_ID_SHIFT
);
524 i2c_writel(i2c_dev
, packet_header
, I2C_TX_FIFO
);
526 packet_header
= msg
->len
- 1;
527 i2c_writel(i2c_dev
, packet_header
, I2C_TX_FIFO
);
529 packet_header
= I2C_HEADER_IE_ENABLE
;
530 if (end_state
== MSG_END_CONTINUE
)
531 packet_header
|= I2C_HEADER_CONTINUE_XFER
;
532 else if (end_state
== MSG_END_REPEAT_START
)
533 packet_header
|= I2C_HEADER_REPEAT_START
;
534 if (msg
->flags
& I2C_M_TEN
) {
535 packet_header
|= msg
->addr
;
536 packet_header
|= I2C_HEADER_10BIT_ADDR
;
538 packet_header
|= msg
->addr
<< I2C_HEADER_SLAVE_ADDR_SHIFT
;
540 if (msg
->flags
& I2C_M_IGNORE_NAK
)
541 packet_header
|= I2C_HEADER_CONT_ON_NAK
;
542 if (msg
->flags
& I2C_M_RD
)
543 packet_header
|= I2C_HEADER_READ
;
544 i2c_writel(i2c_dev
, packet_header
, I2C_TX_FIFO
);
546 if (!(msg
->flags
& I2C_M_RD
))
547 tegra_i2c_fill_tx_fifo(i2c_dev
);
549 int_mask
= I2C_INT_NO_ACK
| I2C_INT_ARBITRATION_LOST
;
550 if (msg
->flags
& I2C_M_RD
)
551 int_mask
|= I2C_INT_RX_FIFO_DATA_REQ
;
552 else if (i2c_dev
->msg_buf_remaining
)
553 int_mask
|= I2C_INT_TX_FIFO_DATA_REQ
;
554 tegra_i2c_unmask_irq(i2c_dev
, int_mask
);
555 dev_dbg(i2c_dev
->dev
, "unmasked irq: %02x\n",
556 i2c_readl(i2c_dev
, I2C_INT_MASK
));
558 ret
= wait_for_completion_timeout(&i2c_dev
->msg_complete
, TEGRA_I2C_TIMEOUT
);
559 tegra_i2c_mask_irq(i2c_dev
, int_mask
);
561 if (WARN_ON(ret
== 0)) {
562 dev_err(i2c_dev
->dev
, "i2c transfer timed out\n");
564 tegra_i2c_init(i2c_dev
);
568 dev_dbg(i2c_dev
->dev
, "transfer complete: %d %d %d\n",
569 ret
, completion_done(&i2c_dev
->msg_complete
), i2c_dev
->msg_err
);
571 if (likely(i2c_dev
->msg_err
== I2C_ERR_NONE
))
575 * NACK interrupt is generated before the I2C controller generates the
576 * STOP condition on the bus. So wait for 2 clock periods before resetting
577 * the controller so that STOP condition has been delivered properly.
579 if (i2c_dev
->msg_err
== I2C_ERR_NO_ACK
)
580 udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev
->bus_clk_rate
));
582 tegra_i2c_init(i2c_dev
);
583 if (i2c_dev
->msg_err
== I2C_ERR_NO_ACK
) {
584 if (msg
->flags
& I2C_M_IGNORE_NAK
)
592 static int tegra_i2c_xfer(struct i2c_adapter
*adap
, struct i2c_msg msgs
[],
595 struct tegra_i2c_dev
*i2c_dev
= i2c_get_adapdata(adap
);
599 if (i2c_dev
->is_suspended
)
602 tegra_i2c_clock_enable(i2c_dev
);
603 for (i
= 0; i
< num
; i
++) {
604 enum msg_end_type end_type
= MSG_END_STOP
;
606 if (msgs
[i
+ 1].flags
& I2C_M_NOSTART
)
607 end_type
= MSG_END_CONTINUE
;
609 end_type
= MSG_END_REPEAT_START
;
611 ret
= tegra_i2c_xfer_msg(i2c_dev
, &msgs
[i
], end_type
);
615 tegra_i2c_clock_disable(i2c_dev
);
619 static u32
tegra_i2c_func(struct i2c_adapter
*adap
)
621 struct tegra_i2c_dev
*i2c_dev
= i2c_get_adapdata(adap
);
622 u32 ret
= I2C_FUNC_I2C
| I2C_FUNC_SMBUS_EMUL
| I2C_FUNC_10BIT_ADDR
|
623 I2C_FUNC_PROTOCOL_MANGLING
;
625 if (i2c_dev
->hw
->has_continue_xfer_support
)
626 ret
|= I2C_FUNC_NOSTART
;
630 static const struct i2c_algorithm tegra_i2c_algo
= {
631 .master_xfer
= tegra_i2c_xfer
,
632 .functionality
= tegra_i2c_func
,
635 static const struct tegra_i2c_hw_feature tegra20_i2c_hw
= {
636 .has_continue_xfer_support
= false,
639 static const struct tegra_i2c_hw_feature tegra30_i2c_hw
= {
640 .has_continue_xfer_support
= true,
643 #if defined(CONFIG_OF)
644 /* Match table for of_platform binding */
645 static const struct of_device_id tegra_i2c_of_match
[] __devinitconst
= {
646 { .compatible
= "nvidia,tegra30-i2c", .data
= &tegra30_i2c_hw
, },
647 { .compatible
= "nvidia,tegra20-i2c", .data
= &tegra20_i2c_hw
, },
648 { .compatible
= "nvidia,tegra20-i2c-dvc", .data
= &tegra20_i2c_hw
, },
651 MODULE_DEVICE_TABLE(of
, tegra_i2c_of_match
);
654 static int __devinit
tegra_i2c_probe(struct platform_device
*pdev
)
656 struct tegra_i2c_dev
*i2c_dev
;
657 struct tegra_i2c_platform_data
*pdata
= pdev
->dev
.platform_data
;
658 struct resource
*res
;
660 struct clk
*fast_clk
;
661 const unsigned int *prop
;
666 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
668 dev_err(&pdev
->dev
, "no mem resource\n");
672 base
= devm_request_and_ioremap(&pdev
->dev
, res
);
674 dev_err(&pdev
->dev
, "Cannot request/ioremap I2C registers\n");
675 return -EADDRNOTAVAIL
;
678 res
= platform_get_resource(pdev
, IORESOURCE_IRQ
, 0);
680 dev_err(&pdev
->dev
, "no irq resource\n");
685 div_clk
= devm_clk_get(&pdev
->dev
, "div-clk");
686 if (IS_ERR(div_clk
)) {
687 dev_err(&pdev
->dev
, "missing controller clock");
688 return PTR_ERR(div_clk
);
691 fast_clk
= devm_clk_get(&pdev
->dev
, "fast-clk");
692 if (IS_ERR(fast_clk
)) {
693 dev_err(&pdev
->dev
, "missing bus clock");
694 return PTR_ERR(fast_clk
);
697 i2c_dev
= devm_kzalloc(&pdev
->dev
, sizeof(*i2c_dev
), GFP_KERNEL
);
699 dev_err(&pdev
->dev
, "Could not allocate struct tegra_i2c_dev");
703 i2c_dev
->base
= base
;
704 i2c_dev
->div_clk
= div_clk
;
705 i2c_dev
->fast_clk
= fast_clk
;
706 i2c_dev
->adapter
.algo
= &tegra_i2c_algo
;
708 i2c_dev
->cont_id
= pdev
->id
;
709 i2c_dev
->dev
= &pdev
->dev
;
711 i2c_dev
->bus_clk_rate
= 100000; /* default clock rate */
713 i2c_dev
->bus_clk_rate
= pdata
->bus_clk_rate
;
715 } else if (i2c_dev
->dev
->of_node
) { /* if there is a device tree node ... */
716 prop
= of_get_property(i2c_dev
->dev
->of_node
,
717 "clock-frequency", NULL
);
719 i2c_dev
->bus_clk_rate
= be32_to_cpup(prop
);
722 i2c_dev
->hw
= &tegra20_i2c_hw
;
724 if (pdev
->dev
.of_node
) {
725 const struct of_device_id
*match
;
726 match
= of_match_device(of_match_ptr(tegra_i2c_of_match
),
728 i2c_dev
->hw
= match
->data
;
729 i2c_dev
->is_dvc
= of_device_is_compatible(pdev
->dev
.of_node
,
730 "nvidia,tegra20-i2c-dvc");
731 } else if (pdev
->id
== 3) {
734 init_completion(&i2c_dev
->msg_complete
);
736 platform_set_drvdata(pdev
, i2c_dev
);
738 ret
= tegra_i2c_init(i2c_dev
);
740 dev_err(&pdev
->dev
, "Failed to initialize i2c controller");
744 ret
= devm_request_irq(&pdev
->dev
, i2c_dev
->irq
,
745 tegra_i2c_isr
, 0, pdev
->name
, i2c_dev
);
747 dev_err(&pdev
->dev
, "Failed to request irq %i\n", i2c_dev
->irq
);
751 i2c_set_adapdata(&i2c_dev
->adapter
, i2c_dev
);
752 i2c_dev
->adapter
.owner
= THIS_MODULE
;
753 i2c_dev
->adapter
.class = I2C_CLASS_HWMON
;
754 strlcpy(i2c_dev
->adapter
.name
, "Tegra I2C adapter",
755 sizeof(i2c_dev
->adapter
.name
));
756 i2c_dev
->adapter
.algo
= &tegra_i2c_algo
;
757 i2c_dev
->adapter
.dev
.parent
= &pdev
->dev
;
758 i2c_dev
->adapter
.nr
= pdev
->id
;
759 i2c_dev
->adapter
.dev
.of_node
= pdev
->dev
.of_node
;
761 ret
= i2c_add_numbered_adapter(&i2c_dev
->adapter
);
763 dev_err(&pdev
->dev
, "Failed to add I2C adapter\n");
767 of_i2c_register_devices(&i2c_dev
->adapter
);
772 static int __devexit
tegra_i2c_remove(struct platform_device
*pdev
)
774 struct tegra_i2c_dev
*i2c_dev
= platform_get_drvdata(pdev
);
775 i2c_del_adapter(&i2c_dev
->adapter
);
779 #ifdef CONFIG_PM_SLEEP
780 static int tegra_i2c_suspend(struct device
*dev
)
782 struct tegra_i2c_dev
*i2c_dev
= dev_get_drvdata(dev
);
784 i2c_lock_adapter(&i2c_dev
->adapter
);
785 i2c_dev
->is_suspended
= true;
786 i2c_unlock_adapter(&i2c_dev
->adapter
);
791 static int tegra_i2c_resume(struct device
*dev
)
793 struct tegra_i2c_dev
*i2c_dev
= dev_get_drvdata(dev
);
796 i2c_lock_adapter(&i2c_dev
->adapter
);
798 ret
= tegra_i2c_init(i2c_dev
);
801 i2c_unlock_adapter(&i2c_dev
->adapter
);
805 i2c_dev
->is_suspended
= false;
807 i2c_unlock_adapter(&i2c_dev
->adapter
);
812 static SIMPLE_DEV_PM_OPS(tegra_i2c_pm
, tegra_i2c_suspend
, tegra_i2c_resume
);
813 #define TEGRA_I2C_PM (&tegra_i2c_pm)
815 #define TEGRA_I2C_PM NULL
818 static struct platform_driver tegra_i2c_driver
= {
819 .probe
= tegra_i2c_probe
,
820 .remove
= __devexit_p(tegra_i2c_remove
),
823 .owner
= THIS_MODULE
,
824 .of_match_table
= of_match_ptr(tegra_i2c_of_match
),
829 static int __init
tegra_i2c_init_driver(void)
831 return platform_driver_register(&tegra_i2c_driver
);
834 static void __exit
tegra_i2c_exit_driver(void)
836 platform_driver_unregister(&tegra_i2c_driver
);
839 subsys_initcall(tegra_i2c_init_driver
);
840 module_exit(tegra_i2c_exit_driver
);
842 MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver");
843 MODULE_AUTHOR("Colin Cross");
844 MODULE_LICENSE("GPL v2");