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[linux.git] / drivers / i2c / busses / i2c-tegra.c
1 /*
2  * drivers/i2c/busses/i2c-tegra.c
3  *
4  * Copyright (C) 2010 Google, Inc.
5  * Author: Colin Cross <ccross@android.com>
6  *
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.
10  *
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.
15  *
16  */
17
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>
24 #include <linux/io.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>
34
35 #include <asm/unaligned.h>
36
37 #define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000))
38 #define BYTES_PER_FIFO_WORD 4
39
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
77
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)
86
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
91
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)
96
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
107
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)
112
113 #define I2C_CLKEN_OVERRIDE                      0x090
114 #define I2C_MST_CORE_CLKEN_OVR                  BIT(0)
115
116 #define I2C_CONFIG_LOAD_TIMEOUT                 1000000
117
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)
123
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
129
130 /*
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.
136  */
137 enum msg_end_type {
138         MSG_END_STOP,
139         MSG_END_REPEAT_START,
140         MSG_END_CONTINUE,
141 };
142
143 /**
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
150  *              fast-clk.
151  * @has_config_load_reg: Has the config load register to load the new
152  *              configuration.
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
156  *              source.
157  */
158
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;
169         bool has_mst_fifo;
170 };
171
172 /**
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
189  */
190 struct tegra_i2c_dev {
191         struct device *dev;
192         const struct tegra_i2c_hw_feature *hw;
193         struct i2c_adapter adapter;
194         struct clk *div_clk;
195         struct clk *fast_clk;
196         struct reset_control *rst;
197         void __iomem *base;
198         int cont_id;
199         int irq;
200         bool irq_disabled;
201         int is_dvc;
202         struct completion msg_complete;
203         int msg_err;
204         u8 *msg_buf;
205         size_t msg_buf_remaining;
206         int msg_read;
207         u32 bus_clk_rate;
208         u16 clk_divisor_non_hs_mode;
209         bool is_multimaster_mode;
210         spinlock_t xfer_lock;
211 };
212
213 static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
214                        unsigned long reg)
215 {
216         writel(val, i2c_dev->base + reg);
217 }
218
219 static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
220 {
221         return readl(i2c_dev->base + reg);
222 }
223
224 /*
225  * i2c_writel and i2c_readl will offset the register if necessary to talk
226  * to the I2C block inside the DVC block
227  */
228 static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev,
229         unsigned long reg)
230 {
231         if (i2c_dev->is_dvc)
232                 reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40;
233         return reg;
234 }
235
236 static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
237         unsigned long reg)
238 {
239         writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
240
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));
244 }
245
246 static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
247 {
248         return readl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
249 }
250
251 static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data,
252         unsigned long reg, int len)
253 {
254         writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
255 }
256
257 static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data,
258         unsigned long reg, int len)
259 {
260         readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
261 }
262
263 static void tegra_i2c_mask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask)
264 {
265         u32 int_mask;
266
267         int_mask = i2c_readl(i2c_dev, I2C_INT_MASK) & ~mask;
268         i2c_writel(i2c_dev, int_mask, I2C_INT_MASK);
269 }
270
271 static void tegra_i2c_unmask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask)
272 {
273         u32 int_mask;
274
275         int_mask = i2c_readl(i2c_dev, I2C_INT_MASK) | mask;
276         i2c_writel(i2c_dev, int_mask, I2C_INT_MASK);
277 }
278
279 static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev)
280 {
281         unsigned long timeout = jiffies + HZ;
282         unsigned int offset;
283         u32 mask, val;
284
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;
289         } else {
290                 mask = I2C_FIFO_CONTROL_TX_FLUSH |
291                        I2C_FIFO_CONTROL_RX_FLUSH;
292                 offset = I2C_FIFO_CONTROL;
293         }
294
295         val = i2c_readl(i2c_dev, offset);
296         val |= mask;
297         i2c_writel(i2c_dev, val, offset);
298
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");
302                         return -ETIMEDOUT;
303                 }
304                 msleep(1);
305         }
306         return 0;
307 }
308
309 static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
310 {
311         u32 val;
312         int rx_fifo_avail;
313         u8 *buf = i2c_dev->msg_buf;
314         size_t buf_remaining = i2c_dev->msg_buf_remaining;
315         int words_to_transfer;
316
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;
321         } else {
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;
325         }
326
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;
331
332         i2c_readsl(i2c_dev, buf, I2C_RX_FIFO, words_to_transfer);
333
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;
337
338         /*
339          * If there is a partial word at the end of buf, handle it manually to
340          * prevent overwriting past the end of buf
341          */
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);
347                 buf_remaining = 0;
348                 rx_fifo_avail--;
349         }
350
351         BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
352         i2c_dev->msg_buf_remaining = buf_remaining;
353         i2c_dev->msg_buf = buf;
354
355         return 0;
356 }
357
358 static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
359 {
360         u32 val;
361         int tx_fifo_avail;
362         u8 *buf = i2c_dev->msg_buf;
363         size_t buf_remaining = i2c_dev->msg_buf_remaining;
364         int words_to_transfer;
365
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;
370         } else {
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;
374         }
375
376         /* Rounds down to not include partial word at the end of buf */
377         words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD;
378
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;
383
384                 /*
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.
390                  */
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;
396                 barrier();
397
398                 i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer);
399
400                 buf += words_to_transfer * BYTES_PER_FIFO_WORD;
401         }
402
403         /*
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.
407          */
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);
412
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;
416                 barrier();
417
418                 i2c_writel(i2c_dev, val, I2C_TX_FIFO);
419         }
420
421         return 0;
422 }
423
424 /*
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
430  */
431 static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev)
432 {
433         u32 val;
434
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);
439
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);
443 }
444
445 static int tegra_i2c_runtime_resume(struct device *dev)
446 {
447         struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
448         int ret;
449
450         ret = pinctrl_pm_select_default_state(i2c_dev->dev);
451         if (ret)
452                 return ret;
453
454         if (!i2c_dev->hw->has_single_clk_source) {
455                 ret = clk_enable(i2c_dev->fast_clk);
456                 if (ret < 0) {
457                         dev_err(i2c_dev->dev,
458                                 "Enabling fast clk failed, err %d\n", ret);
459                         return ret;
460                 }
461         }
462
463         ret = clk_enable(i2c_dev->div_clk);
464         if (ret < 0) {
465                 dev_err(i2c_dev->dev,
466                         "Enabling div clk failed, err %d\n", ret);
467                 clk_disable(i2c_dev->fast_clk);
468                 return ret;
469         }
470
471         return 0;
472 }
473
474 static int tegra_i2c_runtime_suspend(struct device *dev)
475 {
476         struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
477
478         clk_disable(i2c_dev->div_clk);
479         if (!i2c_dev->hw->has_single_clk_source)
480                 clk_disable(i2c_dev->fast_clk);
481
482         return pinctrl_pm_select_idle_state(i2c_dev->dev);
483 }
484
485 static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev)
486 {
487         unsigned long reg_offset;
488         void __iomem *addr;
489         u32 val;
490         int err;
491
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);
496                 if (in_interrupt())
497                         err = readl_poll_timeout_atomic(addr, val, val == 0,
498                                         1000, I2C_CONFIG_LOAD_TIMEOUT);
499                 else
500                         err = readl_poll_timeout(addr, val, val == 0,
501                                         1000, I2C_CONFIG_LOAD_TIMEOUT);
502
503                 if (err) {
504                         dev_warn(i2c_dev->dev,
505                                  "timeout waiting for config load\n");
506                         return err;
507                 }
508         }
509
510         return 0;
511 }
512
513 static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
514 {
515         u32 val;
516         int err;
517         u32 clk_divisor;
518
519         err = pm_runtime_get_sync(i2c_dev->dev);
520         if (err < 0) {
521                 dev_err(i2c_dev->dev, "runtime resume failed %d\n", err);
522                 return err;
523         }
524
525         reset_control_assert(i2c_dev->rst);
526         udelay(2);
527         reset_control_deassert(i2c_dev->rst);
528
529         if (i2c_dev->is_dvc)
530                 tegra_dvc_init(i2c_dev);
531
532         val = I2C_CNFG_NEW_MASTER_FSM | I2C_CNFG_PACKET_MODE_EN |
533                 (0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT);
534
535         if (i2c_dev->hw->has_multi_master_mode)
536                 val |= I2C_CNFG_MULTI_MASTER_MODE;
537
538         i2c_writel(i2c_dev, val, I2C_CNFG);
539         i2c_writel(i2c_dev, 0, I2C_INT_MASK);
540
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);
546
547         if (!i2c_dev->is_dvc) {
548                 u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG);
549
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);
554         }
555
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);
560         } else {
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);
564         }
565
566         err = tegra_i2c_flush_fifos(i2c_dev);
567         if (err)
568                 goto err;
569
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);
572
573         err = tegra_i2c_wait_for_config_load(i2c_dev);
574         if (err)
575                 goto err;
576
577         if (i2c_dev->irq_disabled) {
578                 i2c_dev->irq_disabled = false;
579                 enable_irq(i2c_dev->irq);
580         }
581
582 err:
583         pm_runtime_put(i2c_dev->dev);
584         return err;
585 }
586
587 static int tegra_i2c_disable_packet_mode(struct tegra_i2c_dev *i2c_dev)
588 {
589         u32 cnfg;
590
591         /*
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.
596          */
597         udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->bus_clk_rate));
598
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);
602
603         return tegra_i2c_wait_for_config_load(i2c_dev);
604 }
605
606 static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
607 {
608         u32 status;
609         const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST;
610         struct tegra_i2c_dev *i2c_dev = dev_id;
611         unsigned long flags;
612
613         status = i2c_readl(i2c_dev, I2C_INT_STATUS);
614
615         spin_lock_irqsave(&i2c_dev->xfer_lock, flags);
616         if (status == 0) {
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;
622
623                 if (!i2c_dev->irq_disabled) {
624                         disable_irq_nosync(i2c_dev->irq);
625                         i2c_dev->irq_disabled = true;
626                 }
627                 goto err;
628         }
629
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;
636                 goto err;
637         }
638
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);
642                 else
643                         BUG();
644         }
645
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);
649                 else
650                         tegra_i2c_mask_irq(i2c_dev, I2C_INT_TX_FIFO_DATA_REQ);
651         }
652
653         i2c_writel(i2c_dev, status, I2C_INT_STATUS);
654         if (i2c_dev->is_dvc)
655                 dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
656
657         if (status & I2C_INT_PACKET_XFER_COMPLETE) {
658                 BUG_ON(i2c_dev->msg_buf_remaining);
659                 complete(&i2c_dev->msg_complete);
660         }
661         goto done;
662 err:
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);
668         if (i2c_dev->is_dvc)
669                 dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
670
671         complete(&i2c_dev->msg_complete);
672 done:
673         spin_unlock_irqrestore(&i2c_dev->xfer_lock, flags);
674         return IRQ_HANDLED;
675 }
676
677 static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
678         struct i2c_msg *msg, enum msg_end_type end_state)
679 {
680         u32 packet_header;
681         u32 int_mask;
682         unsigned long time_left;
683         unsigned long flags;
684
685         tegra_i2c_flush_fifos(i2c_dev);
686
687         if (msg->len == 0)
688                 return -EINVAL;
689
690         i2c_dev->msg_buf = msg->buf;
691         i2c_dev->msg_buf_remaining = msg->len;
692         i2c_dev->msg_err = I2C_ERR_NONE;
693         i2c_dev->msg_read = (msg->flags & I2C_M_RD);
694         reinit_completion(&i2c_dev->msg_complete);
695
696         spin_lock_irqsave(&i2c_dev->xfer_lock, flags);
697
698         int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST;
699         tegra_i2c_unmask_irq(i2c_dev, int_mask);
700
701         packet_header = (0 << PACKET_HEADER0_HEADER_SIZE_SHIFT) |
702                         PACKET_HEADER0_PROTOCOL_I2C |
703                         (i2c_dev->cont_id << PACKET_HEADER0_CONT_ID_SHIFT) |
704                         (1 << PACKET_HEADER0_PACKET_ID_SHIFT);
705         i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
706
707         packet_header = msg->len - 1;
708         i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
709
710         packet_header = I2C_HEADER_IE_ENABLE;
711         if (end_state == MSG_END_CONTINUE)
712                 packet_header |= I2C_HEADER_CONTINUE_XFER;
713         else if (end_state == MSG_END_REPEAT_START)
714                 packet_header |= I2C_HEADER_REPEAT_START;
715         if (msg->flags & I2C_M_TEN) {
716                 packet_header |= msg->addr;
717                 packet_header |= I2C_HEADER_10BIT_ADDR;
718         } else {
719                 packet_header |= msg->addr << I2C_HEADER_SLAVE_ADDR_SHIFT;
720         }
721         if (msg->flags & I2C_M_IGNORE_NAK)
722                 packet_header |= I2C_HEADER_CONT_ON_NAK;
723         if (msg->flags & I2C_M_RD)
724                 packet_header |= I2C_HEADER_READ;
725         i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
726
727         if (!(msg->flags & I2C_M_RD))
728                 tegra_i2c_fill_tx_fifo(i2c_dev);
729
730         if (i2c_dev->hw->has_per_pkt_xfer_complete_irq)
731                 int_mask |= I2C_INT_PACKET_XFER_COMPLETE;
732         if (msg->flags & I2C_M_RD)
733                 int_mask |= I2C_INT_RX_FIFO_DATA_REQ;
734         else if (i2c_dev->msg_buf_remaining)
735                 int_mask |= I2C_INT_TX_FIFO_DATA_REQ;
736
737         tegra_i2c_unmask_irq(i2c_dev, int_mask);
738         spin_unlock_irqrestore(&i2c_dev->xfer_lock, flags);
739         dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n",
740                 i2c_readl(i2c_dev, I2C_INT_MASK));
741
742         time_left = wait_for_completion_timeout(&i2c_dev->msg_complete,
743                                                 TEGRA_I2C_TIMEOUT);
744         tegra_i2c_mask_irq(i2c_dev, int_mask);
745
746         if (time_left == 0) {
747                 dev_err(i2c_dev->dev, "i2c transfer timed out\n");
748
749                 tegra_i2c_init(i2c_dev);
750                 return -ETIMEDOUT;
751         }
752
753         dev_dbg(i2c_dev->dev, "transfer complete: %lu %d %d\n",
754                 time_left, completion_done(&i2c_dev->msg_complete),
755                 i2c_dev->msg_err);
756
757         if (likely(i2c_dev->msg_err == I2C_ERR_NONE))
758                 return 0;
759
760         tegra_i2c_init(i2c_dev);
761         if (i2c_dev->msg_err == I2C_ERR_NO_ACK) {
762                 if (msg->flags & I2C_M_IGNORE_NAK)
763                         return 0;
764                 return -EREMOTEIO;
765         }
766
767         return -EIO;
768 }
769
770 static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
771         int num)
772 {
773         struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
774         int i;
775         int ret = 0;
776
777         ret = pm_runtime_get_sync(i2c_dev->dev);
778         if (ret < 0) {
779                 dev_err(i2c_dev->dev, "runtime resume failed %d\n", ret);
780                 return ret;
781         }
782
783         for (i = 0; i < num; i++) {
784                 enum msg_end_type end_type = MSG_END_STOP;
785
786                 if (i < (num - 1)) {
787                         if (msgs[i + 1].flags & I2C_M_NOSTART)
788                                 end_type = MSG_END_CONTINUE;
789                         else
790                                 end_type = MSG_END_REPEAT_START;
791                 }
792                 ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], end_type);
793                 if (ret)
794                         break;
795         }
796
797         pm_runtime_put(i2c_dev->dev);
798
799         return ret ?: i;
800 }
801
802 static u32 tegra_i2c_func(struct i2c_adapter *adap)
803 {
804         struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
805         u32 ret = I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
806                   I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
807
808         if (i2c_dev->hw->has_continue_xfer_support)
809                 ret |= I2C_FUNC_NOSTART;
810         return ret;
811 }
812
813 static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev)
814 {
815         struct device_node *np = i2c_dev->dev->of_node;
816         int ret;
817
818         ret = of_property_read_u32(np, "clock-frequency",
819                         &i2c_dev->bus_clk_rate);
820         if (ret)
821                 i2c_dev->bus_clk_rate = 100000; /* default clock rate */
822
823         i2c_dev->is_multimaster_mode = of_property_read_bool(np,
824                         "multi-master");
825 }
826
827 static const struct i2c_algorithm tegra_i2c_algo = {
828         .master_xfer    = tegra_i2c_xfer,
829         .functionality  = tegra_i2c_func,
830 };
831
832 /* payload size is only 12 bit */
833 static const struct i2c_adapter_quirks tegra_i2c_quirks = {
834         .max_read_len = 4096,
835         .max_write_len = 4096,
836 };
837
838 static const struct tegra_i2c_hw_feature tegra20_i2c_hw = {
839         .has_continue_xfer_support = false,
840         .has_per_pkt_xfer_complete_irq = false,
841         .has_single_clk_source = false,
842         .clk_divisor_hs_mode = 3,
843         .clk_divisor_std_fast_mode = 0,
844         .clk_divisor_fast_plus_mode = 0,
845         .has_config_load_reg = false,
846         .has_multi_master_mode = false,
847         .has_slcg_override_reg = false,
848         .has_mst_fifo = false,
849 };
850
851 static const struct tegra_i2c_hw_feature tegra30_i2c_hw = {
852         .has_continue_xfer_support = true,
853         .has_per_pkt_xfer_complete_irq = false,
854         .has_single_clk_source = false,
855         .clk_divisor_hs_mode = 3,
856         .clk_divisor_std_fast_mode = 0,
857         .clk_divisor_fast_plus_mode = 0,
858         .has_config_load_reg = false,
859         .has_multi_master_mode = false,
860         .has_slcg_override_reg = false,
861         .has_mst_fifo = false,
862 };
863
864 static const struct tegra_i2c_hw_feature tegra114_i2c_hw = {
865         .has_continue_xfer_support = true,
866         .has_per_pkt_xfer_complete_irq = true,
867         .has_single_clk_source = true,
868         .clk_divisor_hs_mode = 1,
869         .clk_divisor_std_fast_mode = 0x19,
870         .clk_divisor_fast_plus_mode = 0x10,
871         .has_config_load_reg = false,
872         .has_multi_master_mode = false,
873         .has_slcg_override_reg = false,
874         .has_mst_fifo = false,
875 };
876
877 static const struct tegra_i2c_hw_feature tegra124_i2c_hw = {
878         .has_continue_xfer_support = true,
879         .has_per_pkt_xfer_complete_irq = true,
880         .has_single_clk_source = true,
881         .clk_divisor_hs_mode = 1,
882         .clk_divisor_std_fast_mode = 0x19,
883         .clk_divisor_fast_plus_mode = 0x10,
884         .has_config_load_reg = true,
885         .has_multi_master_mode = false,
886         .has_slcg_override_reg = true,
887         .has_mst_fifo = false,
888 };
889
890 static const struct tegra_i2c_hw_feature tegra210_i2c_hw = {
891         .has_continue_xfer_support = true,
892         .has_per_pkt_xfer_complete_irq = true,
893         .has_single_clk_source = true,
894         .clk_divisor_hs_mode = 1,
895         .clk_divisor_std_fast_mode = 0x19,
896         .clk_divisor_fast_plus_mode = 0x10,
897         .has_config_load_reg = true,
898         .has_multi_master_mode = true,
899         .has_slcg_override_reg = true,
900         .has_mst_fifo = false,
901 };
902
903 static const struct tegra_i2c_hw_feature tegra194_i2c_hw = {
904         .has_continue_xfer_support = true,
905         .has_per_pkt_xfer_complete_irq = true,
906         .has_single_clk_source = true,
907         .clk_divisor_hs_mode = 1,
908         .clk_divisor_std_fast_mode = 0x19,
909         .clk_divisor_fast_plus_mode = 0x10,
910         .has_config_load_reg = true,
911         .has_multi_master_mode = true,
912         .has_slcg_override_reg = true,
913         .has_mst_fifo = true,
914 };
915
916 /* Match table for of_platform binding */
917 static const struct of_device_id tegra_i2c_of_match[] = {
918         { .compatible = "nvidia,tegra194-i2c", .data = &tegra194_i2c_hw, },
919         { .compatible = "nvidia,tegra210-i2c", .data = &tegra210_i2c_hw, },
920         { .compatible = "nvidia,tegra124-i2c", .data = &tegra124_i2c_hw, },
921         { .compatible = "nvidia,tegra114-i2c", .data = &tegra114_i2c_hw, },
922         { .compatible = "nvidia,tegra30-i2c", .data = &tegra30_i2c_hw, },
923         { .compatible = "nvidia,tegra20-i2c", .data = &tegra20_i2c_hw, },
924         { .compatible = "nvidia,tegra20-i2c-dvc", .data = &tegra20_i2c_hw, },
925         {},
926 };
927 MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
928
929 static int tegra_i2c_probe(struct platform_device *pdev)
930 {
931         struct tegra_i2c_dev *i2c_dev;
932         struct resource *res;
933         struct clk *div_clk;
934         struct clk *fast_clk;
935         void __iomem *base;
936         int irq;
937         int ret = 0;
938         int clk_multiplier = I2C_CLK_MULTIPLIER_STD_FAST_MODE;
939
940         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
941         base = devm_ioremap_resource(&pdev->dev, res);
942         if (IS_ERR(base))
943                 return PTR_ERR(base);
944
945         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
946         if (!res) {
947                 dev_err(&pdev->dev, "no irq resource\n");
948                 return -EINVAL;
949         }
950         irq = res->start;
951
952         div_clk = devm_clk_get(&pdev->dev, "div-clk");
953         if (IS_ERR(div_clk)) {
954                 dev_err(&pdev->dev, "missing controller clock\n");
955                 return PTR_ERR(div_clk);
956         }
957
958         i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
959         if (!i2c_dev)
960                 return -ENOMEM;
961
962         i2c_dev->base = base;
963         i2c_dev->div_clk = div_clk;
964         i2c_dev->adapter.algo = &tegra_i2c_algo;
965         i2c_dev->adapter.quirks = &tegra_i2c_quirks;
966         i2c_dev->irq = irq;
967         i2c_dev->cont_id = pdev->id;
968         i2c_dev->dev = &pdev->dev;
969
970         i2c_dev->rst = devm_reset_control_get_exclusive(&pdev->dev, "i2c");
971         if (IS_ERR(i2c_dev->rst)) {
972                 dev_err(&pdev->dev, "missing controller reset\n");
973                 return PTR_ERR(i2c_dev->rst);
974         }
975
976         tegra_i2c_parse_dt(i2c_dev);
977
978         i2c_dev->hw = of_device_get_match_data(&pdev->dev);
979         i2c_dev->is_dvc = of_device_is_compatible(pdev->dev.of_node,
980                                                   "nvidia,tegra20-i2c-dvc");
981         init_completion(&i2c_dev->msg_complete);
982         spin_lock_init(&i2c_dev->xfer_lock);
983
984         if (!i2c_dev->hw->has_single_clk_source) {
985                 fast_clk = devm_clk_get(&pdev->dev, "fast-clk");
986                 if (IS_ERR(fast_clk)) {
987                         dev_err(&pdev->dev, "missing fast clock\n");
988                         return PTR_ERR(fast_clk);
989                 }
990                 i2c_dev->fast_clk = fast_clk;
991         }
992
993         platform_set_drvdata(pdev, i2c_dev);
994
995         if (!i2c_dev->hw->has_single_clk_source) {
996                 ret = clk_prepare(i2c_dev->fast_clk);
997                 if (ret < 0) {
998                         dev_err(i2c_dev->dev, "Clock prepare failed %d\n", ret);
999                         return ret;
1000                 }
1001         }
1002
1003         i2c_dev->clk_divisor_non_hs_mode =
1004                         i2c_dev->hw->clk_divisor_std_fast_mode;
1005         if (i2c_dev->hw->clk_divisor_fast_plus_mode &&
1006                 (i2c_dev->bus_clk_rate == 1000000))
1007                 i2c_dev->clk_divisor_non_hs_mode =
1008                         i2c_dev->hw->clk_divisor_fast_plus_mode;
1009
1010         clk_multiplier *= (i2c_dev->clk_divisor_non_hs_mode + 1);
1011         ret = clk_set_rate(i2c_dev->div_clk,
1012                            i2c_dev->bus_clk_rate * clk_multiplier);
1013         if (ret) {
1014                 dev_err(i2c_dev->dev, "Clock rate change failed %d\n", ret);
1015                 goto unprepare_fast_clk;
1016         }
1017
1018         ret = clk_prepare(i2c_dev->div_clk);
1019         if (ret < 0) {
1020                 dev_err(i2c_dev->dev, "Clock prepare failed %d\n", ret);
1021                 goto unprepare_fast_clk;
1022         }
1023
1024         pm_runtime_enable(&pdev->dev);
1025         if (!pm_runtime_enabled(&pdev->dev)) {
1026                 ret = tegra_i2c_runtime_resume(&pdev->dev);
1027                 if (ret < 0) {
1028                         dev_err(&pdev->dev, "runtime resume failed\n");
1029                         goto unprepare_div_clk;
1030                 }
1031         }
1032
1033         if (i2c_dev->is_multimaster_mode) {
1034                 ret = clk_enable(i2c_dev->div_clk);
1035                 if (ret < 0) {
1036                         dev_err(i2c_dev->dev, "div_clk enable failed %d\n",
1037                                 ret);
1038                         goto disable_rpm;
1039                 }
1040         }
1041
1042         ret = tegra_i2c_init(i2c_dev);
1043         if (ret) {
1044                 dev_err(&pdev->dev, "Failed to initialize i2c controller\n");
1045                 goto disable_div_clk;
1046         }
1047
1048         ret = devm_request_irq(&pdev->dev, i2c_dev->irq,
1049                         tegra_i2c_isr, 0, dev_name(&pdev->dev), i2c_dev);
1050         if (ret) {
1051                 dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq);
1052                 goto disable_div_clk;
1053         }
1054
1055         i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
1056         i2c_dev->adapter.owner = THIS_MODULE;
1057         i2c_dev->adapter.class = I2C_CLASS_DEPRECATED;
1058         strlcpy(i2c_dev->adapter.name, dev_name(&pdev->dev),
1059                 sizeof(i2c_dev->adapter.name));
1060         i2c_dev->adapter.dev.parent = &pdev->dev;
1061         i2c_dev->adapter.nr = pdev->id;
1062         i2c_dev->adapter.dev.of_node = pdev->dev.of_node;
1063
1064         ret = i2c_add_numbered_adapter(&i2c_dev->adapter);
1065         if (ret)
1066                 goto disable_div_clk;
1067
1068         return 0;
1069
1070 disable_div_clk:
1071         if (i2c_dev->is_multimaster_mode)
1072                 clk_disable(i2c_dev->div_clk);
1073
1074 disable_rpm:
1075         pm_runtime_disable(&pdev->dev);
1076         if (!pm_runtime_status_suspended(&pdev->dev))
1077                 tegra_i2c_runtime_suspend(&pdev->dev);
1078
1079 unprepare_div_clk:
1080         clk_unprepare(i2c_dev->div_clk);
1081
1082 unprepare_fast_clk:
1083         if (!i2c_dev->hw->has_single_clk_source)
1084                 clk_unprepare(i2c_dev->fast_clk);
1085
1086         return ret;
1087 }
1088
1089 static int tegra_i2c_remove(struct platform_device *pdev)
1090 {
1091         struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
1092
1093         i2c_del_adapter(&i2c_dev->adapter);
1094
1095         if (i2c_dev->is_multimaster_mode)
1096                 clk_disable(i2c_dev->div_clk);
1097
1098         pm_runtime_disable(&pdev->dev);
1099         if (!pm_runtime_status_suspended(&pdev->dev))
1100                 tegra_i2c_runtime_suspend(&pdev->dev);
1101
1102         clk_unprepare(i2c_dev->div_clk);
1103         if (!i2c_dev->hw->has_single_clk_source)
1104                 clk_unprepare(i2c_dev->fast_clk);
1105
1106         return 0;
1107 }
1108
1109 #ifdef CONFIG_PM_SLEEP
1110 static const struct dev_pm_ops tegra_i2c_pm = {
1111         SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend, tegra_i2c_runtime_resume,
1112                            NULL)
1113 };
1114 #define TEGRA_I2C_PM    (&tegra_i2c_pm)
1115 #else
1116 #define TEGRA_I2C_PM    NULL
1117 #endif
1118
1119 static struct platform_driver tegra_i2c_driver = {
1120         .probe   = tegra_i2c_probe,
1121         .remove  = tegra_i2c_remove,
1122         .driver  = {
1123                 .name  = "tegra-i2c",
1124                 .of_match_table = tegra_i2c_of_match,
1125                 .pm    = TEGRA_I2C_PM,
1126         },
1127 };
1128
1129 static int __init tegra_i2c_init_driver(void)
1130 {
1131         return platform_driver_register(&tegra_i2c_driver);
1132 }
1133
1134 static void __exit tegra_i2c_exit_driver(void)
1135 {
1136         platform_driver_unregister(&tegra_i2c_driver);
1137 }
1138
1139 subsys_initcall(tegra_i2c_init_driver);
1140 module_exit(tegra_i2c_exit_driver);
1141
1142 MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver");
1143 MODULE_AUTHOR("Colin Cross");
1144 MODULE_LICENSE("GPL v2");