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/of_device.h>
29 #include <linux/module.h>
30 #include <linux/reset.h>
31 #include <linux/pinctrl/consumer.h>
32 #include <linux/pm_runtime.h>
33 #include <linux/iopoll.h>
35 #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 BIT(10)
43 #define I2C_CNFG_NEW_MASTER_FSM BIT(11)
44 #define I2C_CNFG_MULTI_MASTER_MODE BIT(17)
45 #define I2C_STATUS 0x01C
46 #define I2C_SL_CNFG 0x020
47 #define I2C_SL_CNFG_NACK BIT(1)
48 #define I2C_SL_CNFG_NEWSL BIT(2)
49 #define I2C_SL_ADDR1 0x02c
50 #define I2C_SL_ADDR2 0x030
51 #define I2C_TX_FIFO 0x050
52 #define I2C_RX_FIFO 0x054
53 #define I2C_PACKET_TRANSFER_STATUS 0x058
54 #define I2C_FIFO_CONTROL 0x05c
55 #define I2C_FIFO_CONTROL_TX_FLUSH BIT(1)
56 #define I2C_FIFO_CONTROL_RX_FLUSH BIT(0)
57 #define I2C_FIFO_CONTROL_TX_TRIG_SHIFT 5
58 #define I2C_FIFO_CONTROL_RX_TRIG_SHIFT 2
59 #define I2C_FIFO_STATUS 0x060
60 #define I2C_FIFO_STATUS_TX_MASK 0xF0
61 #define I2C_FIFO_STATUS_TX_SHIFT 4
62 #define I2C_FIFO_STATUS_RX_MASK 0x0F
63 #define I2C_FIFO_STATUS_RX_SHIFT 0
64 #define I2C_INT_MASK 0x064
65 #define I2C_INT_STATUS 0x068
66 #define I2C_INT_PACKET_XFER_COMPLETE BIT(7)
67 #define I2C_INT_ALL_PACKETS_XFER_COMPLETE BIT(6)
68 #define I2C_INT_TX_FIFO_OVERFLOW BIT(5)
69 #define I2C_INT_RX_FIFO_UNDERFLOW BIT(4)
70 #define I2C_INT_NO_ACK BIT(3)
71 #define I2C_INT_ARBITRATION_LOST BIT(2)
72 #define I2C_INT_TX_FIFO_DATA_REQ BIT(1)
73 #define I2C_INT_RX_FIFO_DATA_REQ BIT(0)
74 #define I2C_CLK_DIVISOR 0x06c
75 #define I2C_CLK_DIVISOR_STD_FAST_MODE_SHIFT 16
76 #define I2C_CLK_MULTIPLIER_STD_FAST_MODE 8
78 #define DVC_CTRL_REG1 0x000
79 #define DVC_CTRL_REG1_INTR_EN BIT(10)
80 #define DVC_CTRL_REG2 0x004
81 #define DVC_CTRL_REG3 0x008
82 #define DVC_CTRL_REG3_SW_PROG BIT(26)
83 #define DVC_CTRL_REG3_I2C_DONE_INTR_EN BIT(30)
84 #define DVC_STATUS 0x00c
85 #define DVC_STATUS_I2C_DONE_INTR BIT(30)
87 #define I2C_ERR_NONE 0x00
88 #define I2C_ERR_NO_ACK 0x01
89 #define I2C_ERR_ARBITRATION_LOST 0x02
90 #define I2C_ERR_UNKNOWN_INTERRUPT 0x04
92 #define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
93 #define PACKET_HEADER0_PACKET_ID_SHIFT 16
94 #define PACKET_HEADER0_CONT_ID_SHIFT 12
95 #define PACKET_HEADER0_PROTOCOL_I2C BIT(4)
97 #define I2C_HEADER_HIGHSPEED_MODE BIT(22)
98 #define I2C_HEADER_CONT_ON_NAK BIT(21)
99 #define I2C_HEADER_SEND_START_BYTE BIT(20)
100 #define I2C_HEADER_READ BIT(19)
101 #define I2C_HEADER_10BIT_ADDR BIT(18)
102 #define I2C_HEADER_IE_ENABLE BIT(17)
103 #define I2C_HEADER_REPEAT_START BIT(16)
104 #define I2C_HEADER_CONTINUE_XFER BIT(15)
105 #define I2C_HEADER_MASTER_ADDR_SHIFT 12
106 #define I2C_HEADER_SLAVE_ADDR_SHIFT 1
108 #define I2C_CONFIG_LOAD 0x08C
109 #define I2C_MSTR_CONFIG_LOAD BIT(0)
110 #define I2C_SLV_CONFIG_LOAD BIT(1)
111 #define I2C_TIMEOUT_CONFIG_LOAD BIT(2)
113 #define I2C_CLKEN_OVERRIDE 0x090
114 #define I2C_MST_CORE_CLKEN_OVR BIT(0)
116 #define I2C_CONFIG_LOAD_TIMEOUT 1000000
118 #define I2C_MST_FIFO_CONTROL 0x0b4
119 #define I2C_MST_FIFO_CONTROL_RX_FLUSH BIT(0)
120 #define I2C_MST_FIFO_CONTROL_TX_FLUSH BIT(1)
121 #define I2C_MST_FIFO_CONTROL_RX_TRIG(x) (((x) - 1) << 4)
122 #define I2C_MST_FIFO_CONTROL_TX_TRIG(x) (((x) - 1) << 16)
124 #define I2C_MST_FIFO_STATUS 0x0b8
125 #define I2C_MST_FIFO_STATUS_RX_MASK 0xff
126 #define I2C_MST_FIFO_STATUS_RX_SHIFT 0
127 #define I2C_MST_FIFO_STATUS_TX_MASK 0xff0000
128 #define I2C_MST_FIFO_STATUS_TX_SHIFT 16
131 * msg_end_type: The bus control which need to be send at end of transfer.
132 * @MSG_END_STOP: Send stop pulse at end of transfer.
133 * @MSG_END_REPEAT_START: Send repeat start at end of transfer.
134 * @MSG_END_CONTINUE: The following on message is coming and so do not send
135 * stop or repeat start.
139 MSG_END_REPEAT_START
,
144 * struct tegra_i2c_hw_feature : Different HW support on Tegra
145 * @has_continue_xfer_support: Continue transfer supports.
146 * @has_per_pkt_xfer_complete_irq: Has enable/disable capability for transfer
147 * complete interrupt per packet basis.
148 * @has_single_clk_source: The i2c controller has single clock source. Tegra30
149 * and earlier Socs has two clock sources i.e. div-clk and
151 * @has_config_load_reg: Has the config load register to load the new
153 * @clk_divisor_hs_mode: Clock divisor in HS mode.
154 * @clk_divisor_std_fast_mode: Clock divisor in standard/fast mode. It is
155 * applicable if there is no fast clock source i.e. single clock
159 struct tegra_i2c_hw_feature
{
160 bool has_continue_xfer_support
;
161 bool has_per_pkt_xfer_complete_irq
;
162 bool has_single_clk_source
;
163 bool has_config_load_reg
;
164 int clk_divisor_hs_mode
;
165 int clk_divisor_std_fast_mode
;
166 u16 clk_divisor_fast_plus_mode
;
167 bool has_multi_master_mode
;
168 bool has_slcg_override_reg
;
173 * struct tegra_i2c_dev - per device i2c context
174 * @dev: device reference for power management
175 * @hw: Tegra i2c hw feature.
176 * @adapter: core i2c layer adapter information
177 * @div_clk: clock reference for div clock of i2c controller.
178 * @fast_clk: clock reference for fast clock of i2c controller.
179 * @base: ioremapped registers cookie
180 * @cont_id: i2c controller id, used for for packet header
181 * @irq: irq number of transfer complete interrupt
182 * @is_dvc: identifies the DVC i2c controller, has a different register layout
183 * @msg_complete: transfer completion notifier
184 * @msg_err: error code for completed message
185 * @msg_buf: pointer to current message data
186 * @msg_buf_remaining: size of unsent data in the message buffer
187 * @msg_read: identifies read transfers
188 * @bus_clk_rate: current i2c bus clock rate
190 struct tegra_i2c_dev
{
192 const struct tegra_i2c_hw_feature
*hw
;
193 struct i2c_adapter adapter
;
195 struct clk
*fast_clk
;
196 struct reset_control
*rst
;
202 struct completion msg_complete
;
205 size_t msg_buf_remaining
;
208 u16 clk_divisor_non_hs_mode
;
209 bool is_multimaster_mode
;
210 spinlock_t xfer_lock
;
213 static void dvc_writel(struct tegra_i2c_dev
*i2c_dev
, u32 val
,
216 writel(val
, i2c_dev
->base
+ reg
);
219 static u32
dvc_readl(struct tegra_i2c_dev
*i2c_dev
, unsigned long reg
)
221 return readl(i2c_dev
->base
+ reg
);
225 * i2c_writel and i2c_readl will offset the register if necessary to talk
226 * to the I2C block inside the DVC block
228 static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev
*i2c_dev
,
232 reg
+= (reg
>= I2C_TX_FIFO
) ? 0x10 : 0x40;
236 static void i2c_writel(struct tegra_i2c_dev
*i2c_dev
, u32 val
,
239 writel(val
, i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
));
241 /* Read back register to make sure that register writes completed */
242 if (reg
!= I2C_TX_FIFO
)
243 readl(i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
));
246 static u32
i2c_readl(struct tegra_i2c_dev
*i2c_dev
, unsigned long reg
)
248 return readl(i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
));
251 static void i2c_writesl(struct tegra_i2c_dev
*i2c_dev
, void *data
,
252 unsigned long reg
, int len
)
254 writesl(i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
), data
, len
);
257 static void i2c_readsl(struct tegra_i2c_dev
*i2c_dev
, void *data
,
258 unsigned long reg
, int len
)
260 readsl(i2c_dev
->base
+ tegra_i2c_reg_addr(i2c_dev
, reg
), data
, len
);
263 static void tegra_i2c_mask_irq(struct tegra_i2c_dev
*i2c_dev
, u32 mask
)
267 int_mask
= i2c_readl(i2c_dev
, I2C_INT_MASK
) & ~mask
;
268 i2c_writel(i2c_dev
, int_mask
, I2C_INT_MASK
);
271 static void tegra_i2c_unmask_irq(struct tegra_i2c_dev
*i2c_dev
, u32 mask
)
275 int_mask
= i2c_readl(i2c_dev
, I2C_INT_MASK
) | mask
;
276 i2c_writel(i2c_dev
, int_mask
, I2C_INT_MASK
);
279 static int tegra_i2c_flush_fifos(struct tegra_i2c_dev
*i2c_dev
)
281 unsigned long timeout
= jiffies
+ HZ
;
285 if (i2c_dev
->hw
->has_mst_fifo
) {
286 mask
= I2C_MST_FIFO_CONTROL_TX_FLUSH
|
287 I2C_MST_FIFO_CONTROL_RX_FLUSH
;
288 offset
= I2C_MST_FIFO_CONTROL
;
290 mask
= I2C_FIFO_CONTROL_TX_FLUSH
|
291 I2C_FIFO_CONTROL_RX_FLUSH
;
292 offset
= I2C_FIFO_CONTROL
;
295 val
= i2c_readl(i2c_dev
, offset
);
297 i2c_writel(i2c_dev
, val
, offset
);
299 while (i2c_readl(i2c_dev
, offset
) & mask
) {
300 if (time_after(jiffies
, timeout
)) {
301 dev_warn(i2c_dev
->dev
, "timeout waiting for fifo flush\n");
309 static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev
*i2c_dev
)
313 u8
*buf
= i2c_dev
->msg_buf
;
314 size_t buf_remaining
= i2c_dev
->msg_buf_remaining
;
315 int words_to_transfer
;
317 if (i2c_dev
->hw
->has_mst_fifo
) {
318 val
= i2c_readl(i2c_dev
, I2C_MST_FIFO_STATUS
);
319 rx_fifo_avail
= (val
& I2C_MST_FIFO_STATUS_RX_MASK
) >>
320 I2C_MST_FIFO_STATUS_RX_SHIFT
;
322 val
= i2c_readl(i2c_dev
, I2C_FIFO_STATUS
);
323 rx_fifo_avail
= (val
& I2C_FIFO_STATUS_RX_MASK
) >>
324 I2C_FIFO_STATUS_RX_SHIFT
;
327 /* Rounds down to not include partial word at the end of buf */
328 words_to_transfer
= buf_remaining
/ BYTES_PER_FIFO_WORD
;
329 if (words_to_transfer
> rx_fifo_avail
)
330 words_to_transfer
= rx_fifo_avail
;
332 i2c_readsl(i2c_dev
, buf
, I2C_RX_FIFO
, words_to_transfer
);
334 buf
+= words_to_transfer
* BYTES_PER_FIFO_WORD
;
335 buf_remaining
-= words_to_transfer
* BYTES_PER_FIFO_WORD
;
336 rx_fifo_avail
-= words_to_transfer
;
339 * If there is a partial word at the end of buf, handle it manually to
340 * prevent overwriting past the end of buf
342 if (rx_fifo_avail
> 0 && buf_remaining
> 0) {
343 BUG_ON(buf_remaining
> 3);
344 val
= i2c_readl(i2c_dev
, I2C_RX_FIFO
);
345 val
= cpu_to_le32(val
);
346 memcpy(buf
, &val
, buf_remaining
);
351 BUG_ON(rx_fifo_avail
> 0 && buf_remaining
> 0);
352 i2c_dev
->msg_buf_remaining
= buf_remaining
;
353 i2c_dev
->msg_buf
= buf
;
358 static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev
*i2c_dev
)
362 u8
*buf
= i2c_dev
->msg_buf
;
363 size_t buf_remaining
= i2c_dev
->msg_buf_remaining
;
364 int words_to_transfer
;
366 if (i2c_dev
->hw
->has_mst_fifo
) {
367 val
= i2c_readl(i2c_dev
, I2C_MST_FIFO_STATUS
);
368 tx_fifo_avail
= (val
& I2C_MST_FIFO_STATUS_TX_MASK
) >>
369 I2C_MST_FIFO_STATUS_TX_SHIFT
;
371 val
= i2c_readl(i2c_dev
, I2C_FIFO_STATUS
);
372 tx_fifo_avail
= (val
& I2C_FIFO_STATUS_TX_MASK
) >>
373 I2C_FIFO_STATUS_TX_SHIFT
;
376 /* Rounds down to not include partial word at the end of buf */
377 words_to_transfer
= buf_remaining
/ BYTES_PER_FIFO_WORD
;
379 /* It's very common to have < 4 bytes, so optimize that case. */
380 if (words_to_transfer
) {
381 if (words_to_transfer
> tx_fifo_avail
)
382 words_to_transfer
= tx_fifo_avail
;
385 * Update state before writing to FIFO. If this casues us
386 * to finish writing all bytes (AKA buf_remaining goes to 0) we
387 * have a potential for an interrupt (PACKET_XFER_COMPLETE is
388 * not maskable). We need to make sure that the isr sees
389 * buf_remaining as 0 and doesn't call us back re-entrantly.
391 buf_remaining
-= words_to_transfer
* BYTES_PER_FIFO_WORD
;
392 tx_fifo_avail
-= words_to_transfer
;
393 i2c_dev
->msg_buf_remaining
= buf_remaining
;
394 i2c_dev
->msg_buf
= buf
+
395 words_to_transfer
* BYTES_PER_FIFO_WORD
;
398 i2c_writesl(i2c_dev
, buf
, I2C_TX_FIFO
, words_to_transfer
);
400 buf
+= words_to_transfer
* BYTES_PER_FIFO_WORD
;
404 * If there is a partial word at the end of buf, handle it manually to
405 * prevent reading past the end of buf, which could cross a page
406 * boundary and fault.
408 if (tx_fifo_avail
> 0 && buf_remaining
> 0) {
409 BUG_ON(buf_remaining
> 3);
410 memcpy(&val
, buf
, buf_remaining
);
411 val
= le32_to_cpu(val
);
413 /* Again update before writing to FIFO to make sure isr sees. */
414 i2c_dev
->msg_buf_remaining
= 0;
415 i2c_dev
->msg_buf
= NULL
;
418 i2c_writel(i2c_dev
, val
, I2C_TX_FIFO
);
425 * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller)
426 * block. This block is identical to the rest of the I2C blocks, except that
427 * it only supports master mode, it has registers moved around, and it needs
428 * some extra init to get it into I2C mode. The register moves are handled
429 * by i2c_readl and i2c_writel
431 static void tegra_dvc_init(struct tegra_i2c_dev
*i2c_dev
)
435 val
= dvc_readl(i2c_dev
, DVC_CTRL_REG3
);
436 val
|= DVC_CTRL_REG3_SW_PROG
;
437 val
|= DVC_CTRL_REG3_I2C_DONE_INTR_EN
;
438 dvc_writel(i2c_dev
, val
, DVC_CTRL_REG3
);
440 val
= dvc_readl(i2c_dev
, DVC_CTRL_REG1
);
441 val
|= DVC_CTRL_REG1_INTR_EN
;
442 dvc_writel(i2c_dev
, val
, DVC_CTRL_REG1
);
445 static int tegra_i2c_runtime_resume(struct device
*dev
)
447 struct tegra_i2c_dev
*i2c_dev
= dev_get_drvdata(dev
);
450 ret
= pinctrl_pm_select_default_state(i2c_dev
->dev
);
454 if (!i2c_dev
->hw
->has_single_clk_source
) {
455 ret
= clk_enable(i2c_dev
->fast_clk
);
457 dev_err(i2c_dev
->dev
,
458 "Enabling fast clk failed, err %d\n", ret
);
463 ret
= clk_enable(i2c_dev
->div_clk
);
465 dev_err(i2c_dev
->dev
,
466 "Enabling div clk failed, err %d\n", ret
);
467 clk_disable(i2c_dev
->fast_clk
);
474 static int tegra_i2c_runtime_suspend(struct device
*dev
)
476 struct tegra_i2c_dev
*i2c_dev
= dev_get_drvdata(dev
);
478 clk_disable(i2c_dev
->div_clk
);
479 if (!i2c_dev
->hw
->has_single_clk_source
)
480 clk_disable(i2c_dev
->fast_clk
);
482 return pinctrl_pm_select_idle_state(i2c_dev
->dev
);
485 static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev
*i2c_dev
)
487 unsigned long reg_offset
;
492 if (i2c_dev
->hw
->has_config_load_reg
) {
493 reg_offset
= tegra_i2c_reg_addr(i2c_dev
, I2C_CONFIG_LOAD
);
494 addr
= i2c_dev
->base
+ reg_offset
;
495 i2c_writel(i2c_dev
, I2C_MSTR_CONFIG_LOAD
, I2C_CONFIG_LOAD
);
497 err
= readl_poll_timeout_atomic(addr
, val
, val
== 0,
498 1000, I2C_CONFIG_LOAD_TIMEOUT
);
500 err
= readl_poll_timeout(addr
, val
, val
== 0,
501 1000, I2C_CONFIG_LOAD_TIMEOUT
);
504 dev_warn(i2c_dev
->dev
,
505 "timeout waiting for config load\n");
513 static int tegra_i2c_init(struct tegra_i2c_dev
*i2c_dev
)
519 err
= pm_runtime_get_sync(i2c_dev
->dev
);
521 dev_err(i2c_dev
->dev
, "runtime resume failed %d\n", err
);
525 reset_control_assert(i2c_dev
->rst
);
527 reset_control_deassert(i2c_dev
->rst
);
530 tegra_dvc_init(i2c_dev
);
532 val
= I2C_CNFG_NEW_MASTER_FSM
| I2C_CNFG_PACKET_MODE_EN
|
533 (0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT
);
535 if (i2c_dev
->hw
->has_multi_master_mode
)
536 val
|= I2C_CNFG_MULTI_MASTER_MODE
;
538 i2c_writel(i2c_dev
, val
, I2C_CNFG
);
539 i2c_writel(i2c_dev
, 0, I2C_INT_MASK
);
541 /* Make sure clock divisor programmed correctly */
542 clk_divisor
= i2c_dev
->hw
->clk_divisor_hs_mode
;
543 clk_divisor
|= i2c_dev
->clk_divisor_non_hs_mode
<<
544 I2C_CLK_DIVISOR_STD_FAST_MODE_SHIFT
;
545 i2c_writel(i2c_dev
, clk_divisor
, I2C_CLK_DIVISOR
);
547 if (!i2c_dev
->is_dvc
) {
548 u32 sl_cfg
= i2c_readl(i2c_dev
, I2C_SL_CNFG
);
550 sl_cfg
|= I2C_SL_CNFG_NACK
| I2C_SL_CNFG_NEWSL
;
551 i2c_writel(i2c_dev
, sl_cfg
, I2C_SL_CNFG
);
552 i2c_writel(i2c_dev
, 0xfc, I2C_SL_ADDR1
);
553 i2c_writel(i2c_dev
, 0x00, I2C_SL_ADDR2
);
556 if (i2c_dev
->hw
->has_mst_fifo
) {
557 val
= I2C_MST_FIFO_CONTROL_TX_TRIG(8) |
558 I2C_MST_FIFO_CONTROL_RX_TRIG(1);
559 i2c_writel(i2c_dev
, val
, I2C_MST_FIFO_CONTROL
);
561 val
= 7 << I2C_FIFO_CONTROL_TX_TRIG_SHIFT
|
562 0 << I2C_FIFO_CONTROL_RX_TRIG_SHIFT
;
563 i2c_writel(i2c_dev
, val
, I2C_FIFO_CONTROL
);
566 err
= tegra_i2c_flush_fifos(i2c_dev
);
570 if (i2c_dev
->is_multimaster_mode
&& i2c_dev
->hw
->has_slcg_override_reg
)
571 i2c_writel(i2c_dev
, I2C_MST_CORE_CLKEN_OVR
, I2C_CLKEN_OVERRIDE
);
573 err
= tegra_i2c_wait_for_config_load(i2c_dev
);
577 if (i2c_dev
->irq_disabled
) {
578 i2c_dev
->irq_disabled
= false;
579 enable_irq(i2c_dev
->irq
);
583 pm_runtime_put(i2c_dev
->dev
);
587 static int tegra_i2c_disable_packet_mode(struct tegra_i2c_dev
*i2c_dev
)
592 * NACK interrupt is generated before the I2C controller generates
593 * the STOP condition on the bus. So wait for 2 clock periods
594 * before disabling the controller so that the STOP condition has
595 * been delivered properly.
597 udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev
->bus_clk_rate
));
599 cnfg
= i2c_readl(i2c_dev
, I2C_CNFG
);
600 if (cnfg
& I2C_CNFG_PACKET_MODE_EN
)
601 i2c_writel(i2c_dev
, cnfg
& ~I2C_CNFG_PACKET_MODE_EN
, I2C_CNFG
);
603 return tegra_i2c_wait_for_config_load(i2c_dev
);
606 static irqreturn_t
tegra_i2c_isr(int irq
, void *dev_id
)
609 const u32 status_err
= I2C_INT_NO_ACK
| I2C_INT_ARBITRATION_LOST
;
610 struct tegra_i2c_dev
*i2c_dev
= dev_id
;
613 status
= i2c_readl(i2c_dev
, I2C_INT_STATUS
);
615 spin_lock_irqsave(&i2c_dev
->xfer_lock
, flags
);
617 dev_warn(i2c_dev
->dev
, "irq status 0 %08x %08x %08x\n",
618 i2c_readl(i2c_dev
, I2C_PACKET_TRANSFER_STATUS
),
619 i2c_readl(i2c_dev
, I2C_STATUS
),
620 i2c_readl(i2c_dev
, I2C_CNFG
));
621 i2c_dev
->msg_err
|= I2C_ERR_UNKNOWN_INTERRUPT
;
623 if (!i2c_dev
->irq_disabled
) {
624 disable_irq_nosync(i2c_dev
->irq
);
625 i2c_dev
->irq_disabled
= true;
630 if (unlikely(status
& status_err
)) {
631 tegra_i2c_disable_packet_mode(i2c_dev
);
632 if (status
& I2C_INT_NO_ACK
)
633 i2c_dev
->msg_err
|= I2C_ERR_NO_ACK
;
634 if (status
& I2C_INT_ARBITRATION_LOST
)
635 i2c_dev
->msg_err
|= I2C_ERR_ARBITRATION_LOST
;
639 if (i2c_dev
->msg_read
&& (status
& I2C_INT_RX_FIFO_DATA_REQ
)) {
640 if (i2c_dev
->msg_buf_remaining
)
641 tegra_i2c_empty_rx_fifo(i2c_dev
);
646 if (!i2c_dev
->msg_read
&& (status
& I2C_INT_TX_FIFO_DATA_REQ
)) {
647 if (i2c_dev
->msg_buf_remaining
)
648 tegra_i2c_fill_tx_fifo(i2c_dev
);
650 tegra_i2c_mask_irq(i2c_dev
, I2C_INT_TX_FIFO_DATA_REQ
);
653 i2c_writel(i2c_dev
, status
, I2C_INT_STATUS
);
655 dvc_writel(i2c_dev
, DVC_STATUS_I2C_DONE_INTR
, DVC_STATUS
);
657 if (status
& I2C_INT_PACKET_XFER_COMPLETE
) {
658 BUG_ON(i2c_dev
->msg_buf_remaining
);
659 complete(&i2c_dev
->msg_complete
);
663 /* An error occurred, mask all interrupts */
664 tegra_i2c_mask_irq(i2c_dev
, I2C_INT_NO_ACK
| I2C_INT_ARBITRATION_LOST
|
665 I2C_INT_PACKET_XFER_COMPLETE
| I2C_INT_TX_FIFO_DATA_REQ
|
666 I2C_INT_RX_FIFO_DATA_REQ
);
667 i2c_writel(i2c_dev
, status
, I2C_INT_STATUS
);
669 dvc_writel(i2c_dev
, DVC_STATUS_I2C_DONE_INTR
, DVC_STATUS
);
671 complete(&i2c_dev
->msg_complete
);
673 spin_unlock_irqrestore(&i2c_dev
->xfer_lock
, flags
);
677 static int tegra_i2c_xfer_msg(struct tegra_i2c_dev
*i2c_dev
,
678 struct i2c_msg
*msg
, enum msg_end_type end_state
)
682 unsigned long time_left
;
685 tegra_i2c_flush_fifos(i2c_dev
);
687 i2c_dev
->msg_buf
= msg
->buf
;
688 i2c_dev
->msg_buf_remaining
= msg
->len
;
689 i2c_dev
->msg_err
= I2C_ERR_NONE
;
690 i2c_dev
->msg_read
= (msg
->flags
& I2C_M_RD
);
691 reinit_completion(&i2c_dev
->msg_complete
);
693 spin_lock_irqsave(&i2c_dev
->xfer_lock
, flags
);
695 int_mask
= I2C_INT_NO_ACK
| I2C_INT_ARBITRATION_LOST
;
696 tegra_i2c_unmask_irq(i2c_dev
, int_mask
);
698 packet_header
= (0 << PACKET_HEADER0_HEADER_SIZE_SHIFT
) |
699 PACKET_HEADER0_PROTOCOL_I2C
|
700 (i2c_dev
->cont_id
<< PACKET_HEADER0_CONT_ID_SHIFT
) |
701 (1 << PACKET_HEADER0_PACKET_ID_SHIFT
);
702 i2c_writel(i2c_dev
, packet_header
, I2C_TX_FIFO
);
704 packet_header
= msg
->len
- 1;
705 i2c_writel(i2c_dev
, packet_header
, I2C_TX_FIFO
);
707 packet_header
= I2C_HEADER_IE_ENABLE
;
708 if (end_state
== MSG_END_CONTINUE
)
709 packet_header
|= I2C_HEADER_CONTINUE_XFER
;
710 else if (end_state
== MSG_END_REPEAT_START
)
711 packet_header
|= I2C_HEADER_REPEAT_START
;
712 if (msg
->flags
& I2C_M_TEN
) {
713 packet_header
|= msg
->addr
;
714 packet_header
|= I2C_HEADER_10BIT_ADDR
;
716 packet_header
|= msg
->addr
<< I2C_HEADER_SLAVE_ADDR_SHIFT
;
718 if (msg
->flags
& I2C_M_IGNORE_NAK
)
719 packet_header
|= I2C_HEADER_CONT_ON_NAK
;
720 if (msg
->flags
& I2C_M_RD
)
721 packet_header
|= I2C_HEADER_READ
;
722 i2c_writel(i2c_dev
, packet_header
, I2C_TX_FIFO
);
724 if (!(msg
->flags
& I2C_M_RD
))
725 tegra_i2c_fill_tx_fifo(i2c_dev
);
727 if (i2c_dev
->hw
->has_per_pkt_xfer_complete_irq
)
728 int_mask
|= I2C_INT_PACKET_XFER_COMPLETE
;
729 if (msg
->flags
& I2C_M_RD
)
730 int_mask
|= I2C_INT_RX_FIFO_DATA_REQ
;
731 else if (i2c_dev
->msg_buf_remaining
)
732 int_mask
|= I2C_INT_TX_FIFO_DATA_REQ
;
734 tegra_i2c_unmask_irq(i2c_dev
, int_mask
);
735 spin_unlock_irqrestore(&i2c_dev
->xfer_lock
, flags
);
736 dev_dbg(i2c_dev
->dev
, "unmasked irq: %02x\n",
737 i2c_readl(i2c_dev
, I2C_INT_MASK
));
739 time_left
= wait_for_completion_timeout(&i2c_dev
->msg_complete
,
741 tegra_i2c_mask_irq(i2c_dev
, int_mask
);
743 if (time_left
== 0) {
744 dev_err(i2c_dev
->dev
, "i2c transfer timed out\n");
746 tegra_i2c_init(i2c_dev
);
750 dev_dbg(i2c_dev
->dev
, "transfer complete: %lu %d %d\n",
751 time_left
, completion_done(&i2c_dev
->msg_complete
),
754 if (likely(i2c_dev
->msg_err
== I2C_ERR_NONE
))
757 tegra_i2c_init(i2c_dev
);
758 if (i2c_dev
->msg_err
== I2C_ERR_NO_ACK
) {
759 if (msg
->flags
& I2C_M_IGNORE_NAK
)
767 static int tegra_i2c_xfer(struct i2c_adapter
*adap
, struct i2c_msg msgs
[],
770 struct tegra_i2c_dev
*i2c_dev
= i2c_get_adapdata(adap
);
774 ret
= pm_runtime_get_sync(i2c_dev
->dev
);
776 dev_err(i2c_dev
->dev
, "runtime resume failed %d\n", ret
);
780 for (i
= 0; i
< num
; i
++) {
781 enum msg_end_type end_type
= MSG_END_STOP
;
784 if (msgs
[i
+ 1].flags
& I2C_M_NOSTART
)
785 end_type
= MSG_END_CONTINUE
;
787 end_type
= MSG_END_REPEAT_START
;
789 ret
= tegra_i2c_xfer_msg(i2c_dev
, &msgs
[i
], end_type
);
794 pm_runtime_put(i2c_dev
->dev
);
799 static u32
tegra_i2c_func(struct i2c_adapter
*adap
)
801 struct tegra_i2c_dev
*i2c_dev
= i2c_get_adapdata(adap
);
802 u32 ret
= I2C_FUNC_I2C
| (I2C_FUNC_SMBUS_EMUL
& ~I2C_FUNC_SMBUS_QUICK
) |
803 I2C_FUNC_10BIT_ADDR
| I2C_FUNC_PROTOCOL_MANGLING
;
805 if (i2c_dev
->hw
->has_continue_xfer_support
)
806 ret
|= I2C_FUNC_NOSTART
;
810 static void tegra_i2c_parse_dt(struct tegra_i2c_dev
*i2c_dev
)
812 struct device_node
*np
= i2c_dev
->dev
->of_node
;
815 ret
= of_property_read_u32(np
, "clock-frequency",
816 &i2c_dev
->bus_clk_rate
);
818 i2c_dev
->bus_clk_rate
= 100000; /* default clock rate */
820 i2c_dev
->is_multimaster_mode
= of_property_read_bool(np
,
824 static const struct i2c_algorithm tegra_i2c_algo
= {
825 .master_xfer
= tegra_i2c_xfer
,
826 .functionality
= tegra_i2c_func
,
829 /* payload size is only 12 bit */
830 static const struct i2c_adapter_quirks tegra_i2c_quirks
= {
831 .flags
= I2C_AQ_NO_ZERO_LEN
,
832 .max_read_len
= 4096,
833 .max_write_len
= 4096 - 12,
836 static const struct tegra_i2c_hw_feature tegra20_i2c_hw
= {
837 .has_continue_xfer_support
= false,
838 .has_per_pkt_xfer_complete_irq
= false,
839 .has_single_clk_source
= false,
840 .clk_divisor_hs_mode
= 3,
841 .clk_divisor_std_fast_mode
= 0,
842 .clk_divisor_fast_plus_mode
= 0,
843 .has_config_load_reg
= false,
844 .has_multi_master_mode
= false,
845 .has_slcg_override_reg
= false,
846 .has_mst_fifo
= false,
849 static const struct tegra_i2c_hw_feature tegra30_i2c_hw
= {
850 .has_continue_xfer_support
= true,
851 .has_per_pkt_xfer_complete_irq
= false,
852 .has_single_clk_source
= false,
853 .clk_divisor_hs_mode
= 3,
854 .clk_divisor_std_fast_mode
= 0,
855 .clk_divisor_fast_plus_mode
= 0,
856 .has_config_load_reg
= false,
857 .has_multi_master_mode
= false,
858 .has_slcg_override_reg
= false,
859 .has_mst_fifo
= false,
862 static const struct tegra_i2c_hw_feature tegra114_i2c_hw
= {
863 .has_continue_xfer_support
= true,
864 .has_per_pkt_xfer_complete_irq
= true,
865 .has_single_clk_source
= true,
866 .clk_divisor_hs_mode
= 1,
867 .clk_divisor_std_fast_mode
= 0x19,
868 .clk_divisor_fast_plus_mode
= 0x10,
869 .has_config_load_reg
= false,
870 .has_multi_master_mode
= false,
871 .has_slcg_override_reg
= false,
872 .has_mst_fifo
= false,
875 static const struct tegra_i2c_hw_feature tegra124_i2c_hw
= {
876 .has_continue_xfer_support
= true,
877 .has_per_pkt_xfer_complete_irq
= true,
878 .has_single_clk_source
= true,
879 .clk_divisor_hs_mode
= 1,
880 .clk_divisor_std_fast_mode
= 0x19,
881 .clk_divisor_fast_plus_mode
= 0x10,
882 .has_config_load_reg
= true,
883 .has_multi_master_mode
= false,
884 .has_slcg_override_reg
= true,
885 .has_mst_fifo
= false,
888 static const struct tegra_i2c_hw_feature tegra210_i2c_hw
= {
889 .has_continue_xfer_support
= true,
890 .has_per_pkt_xfer_complete_irq
= true,
891 .has_single_clk_source
= true,
892 .clk_divisor_hs_mode
= 1,
893 .clk_divisor_std_fast_mode
= 0x19,
894 .clk_divisor_fast_plus_mode
= 0x10,
895 .has_config_load_reg
= true,
896 .has_multi_master_mode
= true,
897 .has_slcg_override_reg
= true,
898 .has_mst_fifo
= false,
901 static const struct tegra_i2c_hw_feature tegra194_i2c_hw
= {
902 .has_continue_xfer_support
= true,
903 .has_per_pkt_xfer_complete_irq
= true,
904 .has_single_clk_source
= true,
905 .clk_divisor_hs_mode
= 1,
906 .clk_divisor_std_fast_mode
= 0x19,
907 .clk_divisor_fast_plus_mode
= 0x10,
908 .has_config_load_reg
= true,
909 .has_multi_master_mode
= true,
910 .has_slcg_override_reg
= true,
911 .has_mst_fifo
= true,
914 /* Match table for of_platform binding */
915 static const struct of_device_id tegra_i2c_of_match
[] = {
916 { .compatible
= "nvidia,tegra194-i2c", .data
= &tegra194_i2c_hw
, },
917 { .compatible
= "nvidia,tegra210-i2c", .data
= &tegra210_i2c_hw
, },
918 { .compatible
= "nvidia,tegra124-i2c", .data
= &tegra124_i2c_hw
, },
919 { .compatible
= "nvidia,tegra114-i2c", .data
= &tegra114_i2c_hw
, },
920 { .compatible
= "nvidia,tegra30-i2c", .data
= &tegra30_i2c_hw
, },
921 { .compatible
= "nvidia,tegra20-i2c", .data
= &tegra20_i2c_hw
, },
922 { .compatible
= "nvidia,tegra20-i2c-dvc", .data
= &tegra20_i2c_hw
, },
925 MODULE_DEVICE_TABLE(of
, tegra_i2c_of_match
);
927 static int tegra_i2c_probe(struct platform_device
*pdev
)
929 struct tegra_i2c_dev
*i2c_dev
;
930 struct resource
*res
;
932 struct clk
*fast_clk
;
936 int clk_multiplier
= I2C_CLK_MULTIPLIER_STD_FAST_MODE
;
938 res
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
939 base
= devm_ioremap_resource(&pdev
->dev
, res
);
941 return PTR_ERR(base
);
943 res
= platform_get_resource(pdev
, IORESOURCE_IRQ
, 0);
945 dev_err(&pdev
->dev
, "no irq resource\n");
950 div_clk
= devm_clk_get(&pdev
->dev
, "div-clk");
951 if (IS_ERR(div_clk
)) {
952 dev_err(&pdev
->dev
, "missing controller clock\n");
953 return PTR_ERR(div_clk
);
956 i2c_dev
= devm_kzalloc(&pdev
->dev
, sizeof(*i2c_dev
), GFP_KERNEL
);
960 i2c_dev
->base
= base
;
961 i2c_dev
->div_clk
= div_clk
;
962 i2c_dev
->adapter
.algo
= &tegra_i2c_algo
;
963 i2c_dev
->adapter
.quirks
= &tegra_i2c_quirks
;
965 i2c_dev
->cont_id
= pdev
->id
;
966 i2c_dev
->dev
= &pdev
->dev
;
968 i2c_dev
->rst
= devm_reset_control_get_exclusive(&pdev
->dev
, "i2c");
969 if (IS_ERR(i2c_dev
->rst
)) {
970 dev_err(&pdev
->dev
, "missing controller reset\n");
971 return PTR_ERR(i2c_dev
->rst
);
974 tegra_i2c_parse_dt(i2c_dev
);
976 i2c_dev
->hw
= of_device_get_match_data(&pdev
->dev
);
977 i2c_dev
->is_dvc
= of_device_is_compatible(pdev
->dev
.of_node
,
978 "nvidia,tegra20-i2c-dvc");
979 init_completion(&i2c_dev
->msg_complete
);
980 spin_lock_init(&i2c_dev
->xfer_lock
);
982 if (!i2c_dev
->hw
->has_single_clk_source
) {
983 fast_clk
= devm_clk_get(&pdev
->dev
, "fast-clk");
984 if (IS_ERR(fast_clk
)) {
985 dev_err(&pdev
->dev
, "missing fast clock\n");
986 return PTR_ERR(fast_clk
);
988 i2c_dev
->fast_clk
= fast_clk
;
991 platform_set_drvdata(pdev
, i2c_dev
);
993 if (!i2c_dev
->hw
->has_single_clk_source
) {
994 ret
= clk_prepare(i2c_dev
->fast_clk
);
996 dev_err(i2c_dev
->dev
, "Clock prepare failed %d\n", ret
);
1001 i2c_dev
->clk_divisor_non_hs_mode
=
1002 i2c_dev
->hw
->clk_divisor_std_fast_mode
;
1003 if (i2c_dev
->hw
->clk_divisor_fast_plus_mode
&&
1004 (i2c_dev
->bus_clk_rate
== 1000000))
1005 i2c_dev
->clk_divisor_non_hs_mode
=
1006 i2c_dev
->hw
->clk_divisor_fast_plus_mode
;
1008 clk_multiplier
*= (i2c_dev
->clk_divisor_non_hs_mode
+ 1);
1009 ret
= clk_set_rate(i2c_dev
->div_clk
,
1010 i2c_dev
->bus_clk_rate
* clk_multiplier
);
1012 dev_err(i2c_dev
->dev
, "Clock rate change failed %d\n", ret
);
1013 goto unprepare_fast_clk
;
1016 ret
= clk_prepare(i2c_dev
->div_clk
);
1018 dev_err(i2c_dev
->dev
, "Clock prepare failed %d\n", ret
);
1019 goto unprepare_fast_clk
;
1022 pm_runtime_enable(&pdev
->dev
);
1023 if (!pm_runtime_enabled(&pdev
->dev
)) {
1024 ret
= tegra_i2c_runtime_resume(&pdev
->dev
);
1026 dev_err(&pdev
->dev
, "runtime resume failed\n");
1027 goto unprepare_div_clk
;
1031 if (i2c_dev
->is_multimaster_mode
) {
1032 ret
= clk_enable(i2c_dev
->div_clk
);
1034 dev_err(i2c_dev
->dev
, "div_clk enable failed %d\n",
1040 ret
= tegra_i2c_init(i2c_dev
);
1042 dev_err(&pdev
->dev
, "Failed to initialize i2c controller\n");
1043 goto disable_div_clk
;
1046 ret
= devm_request_irq(&pdev
->dev
, i2c_dev
->irq
,
1047 tegra_i2c_isr
, 0, dev_name(&pdev
->dev
), i2c_dev
);
1049 dev_err(&pdev
->dev
, "Failed to request irq %i\n", i2c_dev
->irq
);
1050 goto disable_div_clk
;
1053 i2c_set_adapdata(&i2c_dev
->adapter
, i2c_dev
);
1054 i2c_dev
->adapter
.owner
= THIS_MODULE
;
1055 i2c_dev
->adapter
.class = I2C_CLASS_DEPRECATED
;
1056 strlcpy(i2c_dev
->adapter
.name
, dev_name(&pdev
->dev
),
1057 sizeof(i2c_dev
->adapter
.name
));
1058 i2c_dev
->adapter
.dev
.parent
= &pdev
->dev
;
1059 i2c_dev
->adapter
.nr
= pdev
->id
;
1060 i2c_dev
->adapter
.dev
.of_node
= pdev
->dev
.of_node
;
1062 ret
= i2c_add_numbered_adapter(&i2c_dev
->adapter
);
1064 goto disable_div_clk
;
1069 if (i2c_dev
->is_multimaster_mode
)
1070 clk_disable(i2c_dev
->div_clk
);
1073 pm_runtime_disable(&pdev
->dev
);
1074 if (!pm_runtime_status_suspended(&pdev
->dev
))
1075 tegra_i2c_runtime_suspend(&pdev
->dev
);
1078 clk_unprepare(i2c_dev
->div_clk
);
1081 if (!i2c_dev
->hw
->has_single_clk_source
)
1082 clk_unprepare(i2c_dev
->fast_clk
);
1087 static int tegra_i2c_remove(struct platform_device
*pdev
)
1089 struct tegra_i2c_dev
*i2c_dev
= platform_get_drvdata(pdev
);
1091 i2c_del_adapter(&i2c_dev
->adapter
);
1093 if (i2c_dev
->is_multimaster_mode
)
1094 clk_disable(i2c_dev
->div_clk
);
1096 pm_runtime_disable(&pdev
->dev
);
1097 if (!pm_runtime_status_suspended(&pdev
->dev
))
1098 tegra_i2c_runtime_suspend(&pdev
->dev
);
1100 clk_unprepare(i2c_dev
->div_clk
);
1101 if (!i2c_dev
->hw
->has_single_clk_source
)
1102 clk_unprepare(i2c_dev
->fast_clk
);
1107 #ifdef CONFIG_PM_SLEEP
1108 static const struct dev_pm_ops tegra_i2c_pm
= {
1109 SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend
, tegra_i2c_runtime_resume
,
1112 #define TEGRA_I2C_PM (&tegra_i2c_pm)
1114 #define TEGRA_I2C_PM NULL
1117 static struct platform_driver tegra_i2c_driver
= {
1118 .probe
= tegra_i2c_probe
,
1119 .remove
= tegra_i2c_remove
,
1121 .name
= "tegra-i2c",
1122 .of_match_table
= tegra_i2c_of_match
,
1127 static int __init
tegra_i2c_init_driver(void)
1129 return platform_driver_register(&tegra_i2c_driver
);
1132 static void __exit
tegra_i2c_exit_driver(void)
1134 platform_driver_unregister(&tegra_i2c_driver
);
1137 subsys_initcall(tegra_i2c_init_driver
);
1138 module_exit(tegra_i2c_exit_driver
);
1140 MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver");
1141 MODULE_AUTHOR("Colin Cross");
1142 MODULE_LICENSE("GPL v2");