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i2c-designware: Remove an useless local variable "num"
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CommitLineData
1ab52cf9
BS
1/*
2 * Synopsys Designware I2C adapter driver (master only).
3 *
4 * Based on the TI DAVINCI I2C adapter driver.
5 *
6 * Copyright (C) 2006 Texas Instruments.
7 * Copyright (C) 2007 MontaVista Software Inc.
8 * Copyright (C) 2009 Provigent Ltd.
9 *
10 * ----------------------------------------------------------------------------
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 * ----------------------------------------------------------------------------
26 *
27 */
28#include <linux/kernel.h>
29#include <linux/module.h>
30#include <linux/delay.h>
31#include <linux/i2c.h>
32#include <linux/clk.h>
33#include <linux/errno.h>
34#include <linux/sched.h>
35#include <linux/err.h>
36#include <linux/interrupt.h>
37#include <linux/platform_device.h>
38#include <linux/io.h>
39
40/*
41 * Registers offset
42 */
43#define DW_IC_CON 0x0
44#define DW_IC_TAR 0x4
45#define DW_IC_DATA_CMD 0x10
46#define DW_IC_SS_SCL_HCNT 0x14
47#define DW_IC_SS_SCL_LCNT 0x18
48#define DW_IC_FS_SCL_HCNT 0x1c
49#define DW_IC_FS_SCL_LCNT 0x20
50#define DW_IC_INTR_STAT 0x2c
51#define DW_IC_INTR_MASK 0x30
e28000a3 52#define DW_IC_RAW_INTR_STAT 0x34
1ab52cf9 53#define DW_IC_CLR_INTR 0x40
e28000a3
SK
54#define DW_IC_CLR_RX_UNDER 0x44
55#define DW_IC_CLR_RX_OVER 0x48
56#define DW_IC_CLR_TX_OVER 0x4c
57#define DW_IC_CLR_RD_REQ 0x50
58#define DW_IC_CLR_TX_ABRT 0x54
59#define DW_IC_CLR_RX_DONE 0x58
60#define DW_IC_CLR_ACTIVITY 0x5c
61#define DW_IC_CLR_STOP_DET 0x60
62#define DW_IC_CLR_START_DET 0x64
63#define DW_IC_CLR_GEN_CALL 0x68
1ab52cf9
BS
64#define DW_IC_ENABLE 0x6c
65#define DW_IC_STATUS 0x70
66#define DW_IC_TXFLR 0x74
67#define DW_IC_RXFLR 0x78
68#define DW_IC_COMP_PARAM_1 0xf4
69#define DW_IC_TX_ABRT_SOURCE 0x80
70
71#define DW_IC_CON_MASTER 0x1
72#define DW_IC_CON_SPEED_STD 0x2
73#define DW_IC_CON_SPEED_FAST 0x4
74#define DW_IC_CON_10BITADDR_MASTER 0x10
75#define DW_IC_CON_RESTART_EN 0x20
76#define DW_IC_CON_SLAVE_DISABLE 0x40
77
e28000a3
SK
78#define DW_IC_INTR_RX_UNDER 0x001
79#define DW_IC_INTR_RX_OVER 0x002
80#define DW_IC_INTR_RX_FULL 0x004
81#define DW_IC_INTR_TX_OVER 0x008
82#define DW_IC_INTR_TX_EMPTY 0x010
83#define DW_IC_INTR_RD_REQ 0x020
84#define DW_IC_INTR_TX_ABRT 0x040
85#define DW_IC_INTR_RX_DONE 0x080
86#define DW_IC_INTR_ACTIVITY 0x100
1ab52cf9 87#define DW_IC_INTR_STOP_DET 0x200
e28000a3
SK
88#define DW_IC_INTR_START_DET 0x400
89#define DW_IC_INTR_GEN_CALL 0x800
1ab52cf9
BS
90
91#define DW_IC_STATUS_ACTIVITY 0x1
92
93#define DW_IC_ERR_TX_ABRT 0x1
94
95/*
96 * status codes
97 */
98#define STATUS_IDLE 0x0
99#define STATUS_WRITE_IN_PROGRESS 0x1
100#define STATUS_READ_IN_PROGRESS 0x2
101
102#define TIMEOUT 20 /* ms */
103
104/*
105 * hardware abort codes from the DW_IC_TX_ABRT_SOURCE register
106 *
107 * only expected abort codes are listed here
108 * refer to the datasheet for the full list
109 */
110#define ABRT_7B_ADDR_NOACK 0
111#define ABRT_10ADDR1_NOACK 1
112#define ABRT_10ADDR2_NOACK 2
113#define ABRT_TXDATA_NOACK 3
114#define ABRT_GCALL_NOACK 4
115#define ABRT_GCALL_READ 5
116#define ABRT_SBYTE_ACKDET 7
117#define ABRT_SBYTE_NORSTRT 9
118#define ABRT_10B_RD_NORSTRT 10
119#define ARB_MASTER_DIS 11
120#define ARB_LOST 12
121
122static char *abort_sources[] = {
123 [ABRT_7B_ADDR_NOACK] =
124 "slave address not acknowledged (7bit mode)",
125 [ABRT_10ADDR1_NOACK] =
126 "first address byte not acknowledged (10bit mode)",
127 [ABRT_10ADDR2_NOACK] =
128 "second address byte not acknowledged (10bit mode)",
129 [ABRT_TXDATA_NOACK] =
130 "data not acknowledged",
131 [ABRT_GCALL_NOACK] =
132 "no acknowledgement for a general call",
133 [ABRT_GCALL_READ] =
134 "read after general call",
135 [ABRT_SBYTE_ACKDET] =
136 "start byte acknowledged",
137 [ABRT_SBYTE_NORSTRT] =
138 "trying to send start byte when restart is disabled",
139 [ABRT_10B_RD_NORSTRT] =
140 "trying to read when restart is disabled (10bit mode)",
141 [ARB_MASTER_DIS] =
142 "trying to use disabled adapter",
143 [ARB_LOST] =
144 "lost arbitration",
145};
146
147/**
148 * struct dw_i2c_dev - private i2c-designware data
149 * @dev: driver model device node
150 * @base: IO registers pointer
151 * @cmd_complete: tx completion indicator
152 * @pump_msg: continue in progress transfers
153 * @lock: protect this struct and IO registers
154 * @clk: input reference clock
155 * @cmd_err: run time hadware error code
156 * @msgs: points to an array of messages currently being transfered
157 * @msgs_num: the number of elements in msgs
158 * @msg_write_idx: the element index of the current tx message in the msgs
159 * array
160 * @tx_buf_len: the length of the current tx buffer
161 * @tx_buf: the current tx buffer
162 * @msg_read_idx: the element index of the current rx message in the msgs
163 * array
164 * @rx_buf_len: the length of the current rx buffer
165 * @rx_buf: the current rx buffer
166 * @msg_err: error status of the current transfer
167 * @status: i2c master status, one of STATUS_*
168 * @abort_source: copy of the TX_ABRT_SOURCE register
169 * @irq: interrupt number for the i2c master
170 * @adapter: i2c subsystem adapter node
171 * @tx_fifo_depth: depth of the hardware tx fifo
172 * @rx_fifo_depth: depth of the hardware rx fifo
173 */
174struct dw_i2c_dev {
175 struct device *dev;
176 void __iomem *base;
177 struct completion cmd_complete;
178 struct tasklet_struct pump_msg;
179 struct mutex lock;
180 struct clk *clk;
181 int cmd_err;
182 struct i2c_msg *msgs;
183 int msgs_num;
184 int msg_write_idx;
ed5e1dd5 185 u32 tx_buf_len;
1ab52cf9
BS
186 u8 *tx_buf;
187 int msg_read_idx;
ed5e1dd5 188 u32 rx_buf_len;
1ab52cf9
BS
189 u8 *rx_buf;
190 int msg_err;
191 unsigned int status;
ed5e1dd5 192 u32 abort_source;
1ab52cf9
BS
193 int irq;
194 struct i2c_adapter adapter;
195 unsigned int tx_fifo_depth;
196 unsigned int rx_fifo_depth;
197};
198
199/**
200 * i2c_dw_init() - initialize the designware i2c master hardware
201 * @dev: device private data
202 *
203 * This functions configures and enables the I2C master.
204 * This function is called during I2C init function, and in case of timeout at
205 * run time.
206 */
207static void i2c_dw_init(struct dw_i2c_dev *dev)
208{
209 u32 input_clock_khz = clk_get_rate(dev->clk) / 1000;
ed5e1dd5 210 u32 ic_con;
1ab52cf9
BS
211
212 /* Disable the adapter */
ed5e1dd5 213 writel(0, dev->base + DW_IC_ENABLE);
1ab52cf9
BS
214
215 /* set standard and fast speed deviders for high/low periods */
ed5e1dd5 216 writel((input_clock_khz * 40 / 10000)+1, /* std speed high, 4us */
1ab52cf9 217 dev->base + DW_IC_SS_SCL_HCNT);
ed5e1dd5 218 writel((input_clock_khz * 47 / 10000)+1, /* std speed low, 4.7us */
1ab52cf9 219 dev->base + DW_IC_SS_SCL_LCNT);
ed5e1dd5 220 writel((input_clock_khz * 6 / 10000)+1, /* fast speed high, 0.6us */
1ab52cf9 221 dev->base + DW_IC_FS_SCL_HCNT);
ed5e1dd5 222 writel((input_clock_khz * 13 / 10000)+1, /* fast speed low, 1.3us */
1ab52cf9
BS
223 dev->base + DW_IC_FS_SCL_LCNT);
224
225 /* configure the i2c master */
226 ic_con = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
227 DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
ed5e1dd5 228 writel(ic_con, dev->base + DW_IC_CON);
1ab52cf9
BS
229}
230
231/*
232 * Waiting for bus not busy
233 */
234static int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev)
235{
236 int timeout = TIMEOUT;
237
ed5e1dd5 238 while (readl(dev->base + DW_IC_STATUS) & DW_IC_STATUS_ACTIVITY) {
1ab52cf9
BS
239 if (timeout <= 0) {
240 dev_warn(dev->dev, "timeout waiting for bus ready\n");
241 return -ETIMEDOUT;
242 }
243 timeout--;
244 mdelay(1);
245 }
246
247 return 0;
248}
249
250/*
251 * Initiate low level master read/write transaction.
252 * This function is called from i2c_dw_xfer when starting a transfer.
253 * This function is also called from dw_i2c_pump_msg to continue a transfer
254 * that is longer than the size of the TX FIFO.
255 */
256static void
e77cf232 257i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
1ab52cf9 258{
1ab52cf9 259 struct i2c_msg *msgs = dev->msgs;
ed5e1dd5
SK
260 u32 ic_con, intr_mask;
261 int tx_limit = dev->tx_fifo_depth - readl(dev->base + DW_IC_TXFLR);
262 int rx_limit = dev->rx_fifo_depth - readl(dev->base + DW_IC_RXFLR);
263 u32 addr = msgs[dev->msg_write_idx].addr;
264 u32 buf_len = dev->tx_buf_len;
1ab52cf9
BS
265
266 if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) {
267 /* Disable the adapter */
ed5e1dd5 268 writel(0, dev->base + DW_IC_ENABLE);
1ab52cf9
BS
269
270 /* set the slave (target) address */
ed5e1dd5 271 writel(msgs[dev->msg_write_idx].addr, dev->base + DW_IC_TAR);
1ab52cf9
BS
272
273 /* if the slave address is ten bit address, enable 10BITADDR */
ed5e1dd5 274 ic_con = readl(dev->base + DW_IC_CON);
1ab52cf9
BS
275 if (msgs[dev->msg_write_idx].flags & I2C_M_TEN)
276 ic_con |= DW_IC_CON_10BITADDR_MASTER;
277 else
278 ic_con &= ~DW_IC_CON_10BITADDR_MASTER;
ed5e1dd5 279 writel(ic_con, dev->base + DW_IC_CON);
1ab52cf9
BS
280
281 /* Enable the adapter */
ed5e1dd5 282 writel(1, dev->base + DW_IC_ENABLE);
1ab52cf9
BS
283 }
284
6d2ea487 285 for (; dev->msg_write_idx < dev->msgs_num; dev->msg_write_idx++) {
1ab52cf9
BS
286 /* if target address has changed, we need to
287 * reprogram the target address in the i2c
288 * adapter when we are done with this transfer
289 */
290 if (msgs[dev->msg_write_idx].addr != addr)
291 return;
292
293 if (msgs[dev->msg_write_idx].len == 0) {
294 dev_err(dev->dev,
295 "%s: invalid message length\n", __func__);
296 dev->msg_err = -EINVAL;
297 return;
298 }
299
300 if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) {
301 /* new i2c_msg */
302 dev->tx_buf = msgs[dev->msg_write_idx].buf;
303 buf_len = msgs[dev->msg_write_idx].len;
304 }
305
306 while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) {
307 if (msgs[dev->msg_write_idx].flags & I2C_M_RD) {
ed5e1dd5 308 writel(0x100, dev->base + DW_IC_DATA_CMD);
1ab52cf9
BS
309 rx_limit--;
310 } else
ed5e1dd5 311 writel(*(dev->tx_buf++),
1ab52cf9
BS
312 dev->base + DW_IC_DATA_CMD);
313 tx_limit--; buf_len--;
314 }
315 }
316
317 intr_mask = DW_IC_INTR_STOP_DET | DW_IC_INTR_TX_ABRT;
318 if (buf_len > 0) { /* more bytes to be written */
319 intr_mask |= DW_IC_INTR_TX_EMPTY;
320 dev->status |= STATUS_WRITE_IN_PROGRESS;
321 } else
322 dev->status &= ~STATUS_WRITE_IN_PROGRESS;
ed5e1dd5 323 writel(intr_mask, dev->base + DW_IC_INTR_MASK);
1ab52cf9
BS
324
325 dev->tx_buf_len = buf_len;
326}
327
328static void
78839bd0 329i2c_dw_read(struct dw_i2c_dev *dev)
1ab52cf9 330{
1ab52cf9 331 struct i2c_msg *msgs = dev->msgs;
ed5e1dd5
SK
332 u32 addr = msgs[dev->msg_read_idx].addr;
333 int rx_valid = readl(dev->base + DW_IC_RXFLR);
1ab52cf9 334
6d2ea487 335 for (; dev->msg_read_idx < dev->msgs_num; dev->msg_read_idx++) {
ed5e1dd5 336 u32 len;
1ab52cf9
BS
337 u8 *buf;
338
339 if (!(msgs[dev->msg_read_idx].flags & I2C_M_RD))
340 continue;
341
342 /* different i2c client, reprogram the i2c adapter */
343 if (msgs[dev->msg_read_idx].addr != addr)
344 return;
345
346 if (!(dev->status & STATUS_READ_IN_PROGRESS)) {
347 len = msgs[dev->msg_read_idx].len;
348 buf = msgs[dev->msg_read_idx].buf;
349 } else {
350 len = dev->rx_buf_len;
351 buf = dev->rx_buf;
352 }
353
354 for (; len > 0 && rx_valid > 0; len--, rx_valid--)
ed5e1dd5 355 *buf++ = readl(dev->base + DW_IC_DATA_CMD);
1ab52cf9
BS
356
357 if (len > 0) {
358 dev->status |= STATUS_READ_IN_PROGRESS;
359 dev->rx_buf_len = len;
360 dev->rx_buf = buf;
361 return;
362 } else
363 dev->status &= ~STATUS_READ_IN_PROGRESS;
364 }
365}
366
367/*
368 * Prepare controller for a transaction and call i2c_dw_xfer_msg
369 */
370static int
371i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
372{
373 struct dw_i2c_dev *dev = i2c_get_adapdata(adap);
374 int ret;
375
376 dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num);
377
378 mutex_lock(&dev->lock);
379
380 INIT_COMPLETION(dev->cmd_complete);
381 dev->msgs = msgs;
382 dev->msgs_num = num;
383 dev->cmd_err = 0;
384 dev->msg_write_idx = 0;
385 dev->msg_read_idx = 0;
386 dev->msg_err = 0;
387 dev->status = STATUS_IDLE;
388
389 ret = i2c_dw_wait_bus_not_busy(dev);
390 if (ret < 0)
391 goto done;
392
393 /* start the transfers */
e77cf232 394 i2c_dw_xfer_msg(dev);
1ab52cf9
BS
395
396 /* wait for tx to complete */
397 ret = wait_for_completion_interruptible_timeout(&dev->cmd_complete, HZ);
398 if (ret == 0) {
399 dev_err(dev->dev, "controller timed out\n");
400 i2c_dw_init(dev);
401 ret = -ETIMEDOUT;
402 goto done;
403 } else if (ret < 0)
404 goto done;
405
406 if (dev->msg_err) {
407 ret = dev->msg_err;
408 goto done;
409 }
410
411 /* no error */
412 if (likely(!dev->cmd_err)) {
413 /* read rx fifo, and disable the adapter */
414 do {
78839bd0 415 i2c_dw_read(dev);
1ab52cf9 416 } while (dev->status & STATUS_READ_IN_PROGRESS);
ed5e1dd5 417 writel(0, dev->base + DW_IC_ENABLE);
1ab52cf9
BS
418 ret = num;
419 goto done;
420 }
421
422 /* We have an error */
423 if (dev->cmd_err == DW_IC_ERR_TX_ABRT) {
424 unsigned long abort_source = dev->abort_source;
425 int i;
426
427 for_each_bit(i, &abort_source, ARRAY_SIZE(abort_sources)) {
428 dev_err(dev->dev, "%s: %s\n", __func__, abort_sources[i]);
429 }
430 }
431 ret = -EIO;
432
433done:
434 mutex_unlock(&dev->lock);
435
436 return ret;
437}
438
439static u32 i2c_dw_func(struct i2c_adapter *adap)
440{
441 return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR;
442}
443
444static void dw_i2c_pump_msg(unsigned long data)
445{
446 struct dw_i2c_dev *dev = (struct dw_i2c_dev *) data;
ed5e1dd5 447 u32 intr_mask;
1ab52cf9 448
78839bd0 449 i2c_dw_read(dev);
e77cf232 450 i2c_dw_xfer_msg(dev);
1ab52cf9
BS
451
452 intr_mask = DW_IC_INTR_STOP_DET | DW_IC_INTR_TX_ABRT;
453 if (dev->status & STATUS_WRITE_IN_PROGRESS)
454 intr_mask |= DW_IC_INTR_TX_EMPTY;
ed5e1dd5 455 writel(intr_mask, dev->base + DW_IC_INTR_MASK);
1ab52cf9
BS
456}
457
e28000a3
SK
458static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev)
459{
460 u32 stat;
461
462 /*
463 * The IC_INTR_STAT register just indicates "enabled" interrupts.
464 * Ths unmasked raw version of interrupt status bits are available
465 * in the IC_RAW_INTR_STAT register.
466 *
467 * That is,
468 * stat = readl(IC_INTR_STAT);
469 * equals to,
470 * stat = readl(IC_RAW_INTR_STAT) & readl(IC_INTR_MASK);
471 *
472 * The raw version might be useful for debugging purposes.
473 */
474 stat = readl(dev->base + DW_IC_INTR_STAT);
475
476 /*
477 * Do not use the IC_CLR_INTR register to clear interrupts, or
478 * you'll miss some interrupts, triggered during the period from
479 * readl(IC_INTR_STAT) to readl(IC_CLR_INTR).
480 *
481 * Instead, use the separately-prepared IC_CLR_* registers.
482 */
483 if (stat & DW_IC_INTR_RX_UNDER)
484 readl(dev->base + DW_IC_CLR_RX_UNDER);
485 if (stat & DW_IC_INTR_RX_OVER)
486 readl(dev->base + DW_IC_CLR_RX_OVER);
487 if (stat & DW_IC_INTR_TX_OVER)
488 readl(dev->base + DW_IC_CLR_TX_OVER);
489 if (stat & DW_IC_INTR_RD_REQ)
490 readl(dev->base + DW_IC_CLR_RD_REQ);
491 if (stat & DW_IC_INTR_TX_ABRT) {
492 /*
493 * The IC_TX_ABRT_SOURCE register is cleared whenever
494 * the IC_CLR_TX_ABRT is read. Preserve it beforehand.
495 */
496 dev->abort_source = readl(dev->base + DW_IC_TX_ABRT_SOURCE);
497 readl(dev->base + DW_IC_CLR_TX_ABRT);
498 }
499 if (stat & DW_IC_INTR_RX_DONE)
500 readl(dev->base + DW_IC_CLR_RX_DONE);
501 if (stat & DW_IC_INTR_ACTIVITY)
502 readl(dev->base + DW_IC_CLR_ACTIVITY);
503 if (stat & DW_IC_INTR_STOP_DET)
504 readl(dev->base + DW_IC_CLR_STOP_DET);
505 if (stat & DW_IC_INTR_START_DET)
506 readl(dev->base + DW_IC_CLR_START_DET);
507 if (stat & DW_IC_INTR_GEN_CALL)
508 readl(dev->base + DW_IC_CLR_GEN_CALL);
509
510 return stat;
511}
512
1ab52cf9
BS
513/*
514 * Interrupt service routine. This gets called whenever an I2C interrupt
515 * occurs.
516 */
517static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
518{
519 struct dw_i2c_dev *dev = dev_id;
ed5e1dd5 520 u32 stat;
1ab52cf9 521
e28000a3 522 stat = i2c_dw_read_clear_intrbits(dev);
1ab52cf9 523 dev_dbg(dev->dev, "%s: stat=0x%x\n", __func__, stat);
e28000a3 524
1ab52cf9 525 if (stat & DW_IC_INTR_TX_ABRT) {
1ab52cf9
BS
526 dev->cmd_err |= DW_IC_ERR_TX_ABRT;
527 dev->status = STATUS_IDLE;
528 } else if (stat & DW_IC_INTR_TX_EMPTY)
529 tasklet_schedule(&dev->pump_msg);
530
ed5e1dd5 531 writel(0, dev->base + DW_IC_INTR_MASK); /* disable interrupts */
1ab52cf9
BS
532 if (stat & (DW_IC_INTR_TX_ABRT | DW_IC_INTR_STOP_DET))
533 complete(&dev->cmd_complete);
534
535 return IRQ_HANDLED;
536}
537
538static struct i2c_algorithm i2c_dw_algo = {
539 .master_xfer = i2c_dw_xfer,
540 .functionality = i2c_dw_func,
541};
542
543static int __devinit dw_i2c_probe(struct platform_device *pdev)
544{
545 struct dw_i2c_dev *dev;
546 struct i2c_adapter *adap;
91b52cae
SK
547 struct resource *mem, *ioarea;
548 int irq, r;
1ab52cf9
BS
549
550 /* NOTE: driver uses the static register mapping */
551 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
552 if (!mem) {
553 dev_err(&pdev->dev, "no mem resource?\n");
554 return -EINVAL;
555 }
556
91b52cae
SK
557 irq = platform_get_irq(pdev, 0);
558 if (irq < 0) {
1ab52cf9 559 dev_err(&pdev->dev, "no irq resource?\n");
91b52cae 560 return irq; /* -ENXIO */
1ab52cf9
BS
561 }
562
563 ioarea = request_mem_region(mem->start, resource_size(mem),
564 pdev->name);
565 if (!ioarea) {
566 dev_err(&pdev->dev, "I2C region already claimed\n");
567 return -EBUSY;
568 }
569
570 dev = kzalloc(sizeof(struct dw_i2c_dev), GFP_KERNEL);
571 if (!dev) {
572 r = -ENOMEM;
573 goto err_release_region;
574 }
575
576 init_completion(&dev->cmd_complete);
577 tasklet_init(&dev->pump_msg, dw_i2c_pump_msg, (unsigned long) dev);
578 mutex_init(&dev->lock);
579 dev->dev = get_device(&pdev->dev);
91b52cae 580 dev->irq = irq;
1ab52cf9
BS
581 platform_set_drvdata(pdev, dev);
582
583 dev->clk = clk_get(&pdev->dev, NULL);
584 if (IS_ERR(dev->clk)) {
585 r = -ENODEV;
586 goto err_free_mem;
587 }
588 clk_enable(dev->clk);
589
590 dev->base = ioremap(mem->start, resource_size(mem));
591 if (dev->base == NULL) {
592 dev_err(&pdev->dev, "failure mapping io resources\n");
593 r = -EBUSY;
594 goto err_unuse_clocks;
595 }
596 {
597 u32 param1 = readl(dev->base + DW_IC_COMP_PARAM_1);
598
599 dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
600 dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
601 }
602 i2c_dw_init(dev);
603
ed5e1dd5 604 writel(0, dev->base + DW_IC_INTR_MASK); /* disable IRQ */
1ab52cf9
BS
605 r = request_irq(dev->irq, i2c_dw_isr, 0, pdev->name, dev);
606 if (r) {
607 dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
608 goto err_iounmap;
609 }
610
611 adap = &dev->adapter;
612 i2c_set_adapdata(adap, dev);
613 adap->owner = THIS_MODULE;
614 adap->class = I2C_CLASS_HWMON;
615 strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
616 sizeof(adap->name));
617 adap->algo = &i2c_dw_algo;
618 adap->dev.parent = &pdev->dev;
619
620 adap->nr = pdev->id;
621 r = i2c_add_numbered_adapter(adap);
622 if (r) {
623 dev_err(&pdev->dev, "failure adding adapter\n");
624 goto err_free_irq;
625 }
626
627 return 0;
628
629err_free_irq:
630 free_irq(dev->irq, dev);
631err_iounmap:
632 iounmap(dev->base);
633err_unuse_clocks:
634 clk_disable(dev->clk);
635 clk_put(dev->clk);
636 dev->clk = NULL;
637err_free_mem:
638 platform_set_drvdata(pdev, NULL);
639 put_device(&pdev->dev);
640 kfree(dev);
641err_release_region:
642 release_mem_region(mem->start, resource_size(mem));
643
644 return r;
645}
646
647static int __devexit dw_i2c_remove(struct platform_device *pdev)
648{
649 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
650 struct resource *mem;
651
652 platform_set_drvdata(pdev, NULL);
653 i2c_del_adapter(&dev->adapter);
654 put_device(&pdev->dev);
655
656 clk_disable(dev->clk);
657 clk_put(dev->clk);
658 dev->clk = NULL;
659
ed5e1dd5 660 writel(0, dev->base + DW_IC_ENABLE);
1ab52cf9
BS
661 free_irq(dev->irq, dev);
662 kfree(dev);
663
664 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
665 release_mem_region(mem->start, resource_size(mem));
666 return 0;
667}
668
669/* work with hotplug and coldplug */
670MODULE_ALIAS("platform:i2c_designware");
671
672static struct platform_driver dw_i2c_driver = {
673 .remove = __devexit_p(dw_i2c_remove),
674 .driver = {
675 .name = "i2c_designware",
676 .owner = THIS_MODULE,
677 },
678};
679
680static int __init dw_i2c_init_driver(void)
681{
682 return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe);
683}
684module_init(dw_i2c_init_driver);
685
686static void __exit dw_i2c_exit_driver(void)
687{
688 platform_driver_unregister(&dw_i2c_driver);
689}
690module_exit(dw_i2c_exit_driver);
691
692MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
693MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
694MODULE_LICENSE("GPL");