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da672773 MD |
1 | /* |
2 | * SuperH Mobile I2C Controller | |
3 | * | |
4 | * Copyright (C) 2008 Magnus Damm | |
5 | * | |
6 | * Portions of the code based on out-of-tree driver i2c-sh7343.c | |
7 | * Copyright (c) 2006 Carlos Munoz <carlos@kenati.com> | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License as published by | |
11 | * the Free Software Foundation; either version 2 of the License | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License | |
19 | * along with this program; if not, write to the Free Software | |
20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
21 | */ | |
22 | ||
23 | #include <linux/kernel.h> | |
24 | #include <linux/module.h> | |
25 | #include <linux/init.h> | |
26 | #include <linux/delay.h> | |
27 | #include <linux/platform_device.h> | |
28 | #include <linux/interrupt.h> | |
29 | #include <linux/i2c.h> | |
30 | #include <linux/err.h> | |
f1a3b994 | 31 | #include <linux/pm_runtime.h> |
da672773 MD |
32 | #include <linux/clk.h> |
33 | #include <linux/io.h> | |
5a0e3ad6 | 34 | #include <linux/slab.h> |
da672773 | 35 | |
4eb00c9f MD |
36 | /* Transmit operation: */ |
37 | /* */ | |
38 | /* 0 byte transmit */ | |
39 | /* BUS: S A8 ACK P */ | |
40 | /* IRQ: DTE WAIT */ | |
41 | /* ICIC: */ | |
42 | /* ICCR: 0x94 0x90 */ | |
43 | /* ICDR: A8 */ | |
44 | /* */ | |
45 | /* 1 byte transmit */ | |
46 | /* BUS: S A8 ACK D8(1) ACK P */ | |
47 | /* IRQ: DTE WAIT WAIT */ | |
48 | /* ICIC: -DTE */ | |
49 | /* ICCR: 0x94 0x90 */ | |
50 | /* ICDR: A8 D8(1) */ | |
51 | /* */ | |
52 | /* 2 byte transmit */ | |
53 | /* BUS: S A8 ACK D8(1) ACK D8(2) ACK P */ | |
54 | /* IRQ: DTE WAIT WAIT WAIT */ | |
55 | /* ICIC: -DTE */ | |
56 | /* ICCR: 0x94 0x90 */ | |
57 | /* ICDR: A8 D8(1) D8(2) */ | |
58 | /* */ | |
59 | /* 3 bytes or more, +---------+ gets repeated */ | |
60 | /* */ | |
61 | /* */ | |
62 | /* Receive operation: */ | |
63 | /* */ | |
64 | /* 0 byte receive - not supported since slave may hold SDA low */ | |
65 | /* */ | |
66 | /* 1 byte receive [TX] | [RX] */ | |
67 | /* BUS: S A8 ACK | D8(1) ACK P */ | |
68 | /* IRQ: DTE WAIT | WAIT DTE */ | |
69 | /* ICIC: -DTE | +DTE */ | |
70 | /* ICCR: 0x94 0x81 | 0xc0 */ | |
71 | /* ICDR: A8 | D8(1) */ | |
72 | /* */ | |
73 | /* 2 byte receive [TX]| [RX] */ | |
74 | /* BUS: S A8 ACK | D8(1) ACK D8(2) ACK P */ | |
75 | /* IRQ: DTE WAIT | WAIT WAIT DTE */ | |
76 | /* ICIC: -DTE | +DTE */ | |
77 | /* ICCR: 0x94 0x81 | 0xc0 */ | |
78 | /* ICDR: A8 | D8(1) D8(2) */ | |
79 | /* */ | |
80 | /* 3 byte receive [TX] | [RX] */ | |
81 | /* BUS: S A8 ACK | D8(1) ACK D8(2) ACK D8(3) ACK P */ | |
82 | /* IRQ: DTE WAIT | WAIT WAIT WAIT DTE */ | |
83 | /* ICIC: -DTE | +DTE */ | |
84 | /* ICCR: 0x94 0x81 | 0xc0 */ | |
85 | /* ICDR: A8 | D8(1) D8(2) D8(3) */ | |
86 | /* */ | |
87 | /* 4 bytes or more, this part is repeated +---------+ */ | |
88 | /* */ | |
89 | /* */ | |
90 | /* Interrupt order and BUSY flag */ | |
91 | /* ___ _ */ | |
92 | /* SDA ___\___XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXAAAAAAAAA___/ */ | |
93 | /* SCL \_/1\_/2\_/3\_/4\_/5\_/6\_/7\_/8\___/9\_____/ */ | |
94 | /* */ | |
95 | /* S D7 D6 D5 D4 D3 D2 D1 D0 P */ | |
96 | /* ___ */ | |
97 | /* WAIT IRQ ________________________________/ \___________ */ | |
98 | /* TACK IRQ ____________________________________/ \_______ */ | |
99 | /* DTE IRQ __________________________________________/ \_ */ | |
100 | /* AL IRQ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */ | |
101 | /* _______________________________________________ */ | |
102 | /* BUSY __/ \_ */ | |
103 | /* */ | |
104 | ||
da672773 MD |
105 | enum sh_mobile_i2c_op { |
106 | OP_START = 0, | |
4eb00c9f MD |
107 | OP_TX_FIRST, |
108 | OP_TX, | |
da672773 MD |
109 | OP_TX_STOP, |
110 | OP_TX_TO_RX, | |
4eb00c9f | 111 | OP_RX, |
da672773 | 112 | OP_RX_STOP, |
4eb00c9f | 113 | OP_RX_STOP_DATA, |
da672773 MD |
114 | }; |
115 | ||
116 | struct sh_mobile_i2c_data { | |
117 | struct device *dev; | |
118 | void __iomem *reg; | |
119 | struct i2c_adapter adap; | |
120 | ||
121 | struct clk *clk; | |
122 | u_int8_t iccl; | |
123 | u_int8_t icch; | |
124 | ||
125 | spinlock_t lock; | |
126 | wait_queue_head_t wait; | |
127 | struct i2c_msg *msg; | |
128 | int pos; | |
129 | int sr; | |
130 | }; | |
131 | ||
132 | #define NORMAL_SPEED 100000 /* FAST_SPEED 400000 */ | |
133 | ||
134 | /* Register offsets */ | |
135 | #define ICDR(pd) (pd->reg + 0x00) | |
136 | #define ICCR(pd) (pd->reg + 0x04) | |
137 | #define ICSR(pd) (pd->reg + 0x08) | |
138 | #define ICIC(pd) (pd->reg + 0x0c) | |
139 | #define ICCL(pd) (pd->reg + 0x10) | |
140 | #define ICCH(pd) (pd->reg + 0x14) | |
141 | ||
142 | /* Register bits */ | |
143 | #define ICCR_ICE 0x80 | |
144 | #define ICCR_RACK 0x40 | |
145 | #define ICCR_TRS 0x10 | |
146 | #define ICCR_BBSY 0x04 | |
147 | #define ICCR_SCP 0x01 | |
148 | ||
149 | #define ICSR_SCLM 0x80 | |
150 | #define ICSR_SDAM 0x40 | |
151 | #define SW_DONE 0x20 | |
152 | #define ICSR_BUSY 0x10 | |
153 | #define ICSR_AL 0x08 | |
154 | #define ICSR_TACK 0x04 | |
155 | #define ICSR_WAIT 0x02 | |
156 | #define ICSR_DTE 0x01 | |
157 | ||
158 | #define ICIC_ALE 0x08 | |
159 | #define ICIC_TACKE 0x04 | |
160 | #define ICIC_WAITE 0x02 | |
161 | #define ICIC_DTEE 0x01 | |
162 | ||
163 | static void activate_ch(struct sh_mobile_i2c_data *pd) | |
164 | { | |
a5616bd0 MD |
165 | unsigned long i2c_clk; |
166 | u_int32_t num; | |
167 | u_int32_t denom; | |
168 | u_int32_t tmp; | |
169 | ||
f1a3b994 MD |
170 | /* Wake up device and enable clock */ |
171 | pm_runtime_get_sync(pd->dev); | |
da672773 MD |
172 | clk_enable(pd->clk); |
173 | ||
a5616bd0 MD |
174 | /* Get clock rate after clock is enabled */ |
175 | i2c_clk = clk_get_rate(pd->clk); | |
176 | ||
177 | /* Calculate the value for iccl. From the data sheet: | |
178 | * iccl = (p clock / transfer rate) * (L / (L + H)) | |
179 | * where L and H are the SCL low/high ratio (5/4 in this case). | |
180 | * We also round off the result. | |
181 | */ | |
182 | num = i2c_clk * 5; | |
183 | denom = NORMAL_SPEED * 9; | |
184 | tmp = num * 10 / denom; | |
185 | if (tmp % 10 >= 5) | |
186 | pd->iccl = (u_int8_t)((num/denom) + 1); | |
187 | else | |
188 | pd->iccl = (u_int8_t)(num/denom); | |
189 | ||
190 | /* Calculate the value for icch. From the data sheet: | |
191 | icch = (p clock / transfer rate) * (H / (L + H)) */ | |
192 | num = i2c_clk * 4; | |
193 | tmp = num * 10 / denom; | |
194 | if (tmp % 10 >= 5) | |
195 | pd->icch = (u_int8_t)((num/denom) + 1); | |
196 | else | |
197 | pd->icch = (u_int8_t)(num/denom); | |
198 | ||
da672773 MD |
199 | /* Enable channel and configure rx ack */ |
200 | iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd)); | |
201 | ||
202 | /* Mask all interrupts */ | |
203 | iowrite8(0, ICIC(pd)); | |
204 | ||
205 | /* Set the clock */ | |
206 | iowrite8(pd->iccl, ICCL(pd)); | |
207 | iowrite8(pd->icch, ICCH(pd)); | |
208 | } | |
209 | ||
210 | static void deactivate_ch(struct sh_mobile_i2c_data *pd) | |
211 | { | |
212 | /* Clear/disable interrupts */ | |
213 | iowrite8(0, ICSR(pd)); | |
214 | iowrite8(0, ICIC(pd)); | |
215 | ||
216 | /* Disable channel */ | |
217 | iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd)); | |
218 | ||
f1a3b994 | 219 | /* Disable clock and mark device as idle */ |
da672773 | 220 | clk_disable(pd->clk); |
f1a3b994 | 221 | pm_runtime_put_sync(pd->dev); |
da672773 MD |
222 | } |
223 | ||
224 | static unsigned char i2c_op(struct sh_mobile_i2c_data *pd, | |
225 | enum sh_mobile_i2c_op op, unsigned char data) | |
226 | { | |
227 | unsigned char ret = 0; | |
228 | unsigned long flags; | |
229 | ||
230 | dev_dbg(pd->dev, "op %d, data in 0x%02x\n", op, data); | |
231 | ||
232 | spin_lock_irqsave(&pd->lock, flags); | |
233 | ||
234 | switch (op) { | |
4eb00c9f | 235 | case OP_START: /* issue start and trigger DTE interrupt */ |
da672773 MD |
236 | iowrite8(0x94, ICCR(pd)); |
237 | break; | |
4eb00c9f MD |
238 | case OP_TX_FIRST: /* disable DTE interrupt and write data */ |
239 | iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE, ICIC(pd)); | |
da672773 MD |
240 | iowrite8(data, ICDR(pd)); |
241 | break; | |
4eb00c9f | 242 | case OP_TX: /* write data */ |
da672773 | 243 | iowrite8(data, ICDR(pd)); |
da672773 | 244 | break; |
4eb00c9f | 245 | case OP_TX_STOP: /* write data and issue a stop afterwards */ |
da672773 | 246 | iowrite8(data, ICDR(pd)); |
4eb00c9f MD |
247 | iowrite8(0x90, ICCR(pd)); |
248 | break; | |
249 | case OP_TX_TO_RX: /* select read mode */ | |
da672773 MD |
250 | iowrite8(0x81, ICCR(pd)); |
251 | break; | |
4eb00c9f | 252 | case OP_RX: /* just read data */ |
da672773 MD |
253 | ret = ioread8(ICDR(pd)); |
254 | break; | |
4eb00c9f MD |
255 | case OP_RX_STOP: /* enable DTE interrupt, issue stop */ |
256 | iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE, | |
257 | ICIC(pd)); | |
258 | iowrite8(0xc0, ICCR(pd)); | |
259 | break; | |
260 | case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */ | |
261 | iowrite8(ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE, | |
262 | ICIC(pd)); | |
da672773 MD |
263 | ret = ioread8(ICDR(pd)); |
264 | iowrite8(0xc0, ICCR(pd)); | |
265 | break; | |
266 | } | |
267 | ||
268 | spin_unlock_irqrestore(&pd->lock, flags); | |
269 | ||
270 | dev_dbg(pd->dev, "op %d, data out 0x%02x\n", op, ret); | |
271 | return ret; | |
272 | } | |
273 | ||
4eb00c9f MD |
274 | static int sh_mobile_i2c_is_first_byte(struct sh_mobile_i2c_data *pd) |
275 | { | |
276 | if (pd->pos == -1) | |
277 | return 1; | |
278 | ||
279 | return 0; | |
280 | } | |
281 | ||
282 | static int sh_mobile_i2c_is_last_byte(struct sh_mobile_i2c_data *pd) | |
283 | { | |
284 | if (pd->pos == (pd->msg->len - 1)) | |
285 | return 1; | |
286 | ||
287 | return 0; | |
288 | } | |
289 | ||
290 | static void sh_mobile_i2c_get_data(struct sh_mobile_i2c_data *pd, | |
291 | unsigned char *buf) | |
292 | { | |
293 | switch (pd->pos) { | |
294 | case -1: | |
295 | *buf = (pd->msg->addr & 0x7f) << 1; | |
296 | *buf |= (pd->msg->flags & I2C_M_RD) ? 1 : 0; | |
297 | break; | |
298 | default: | |
299 | *buf = pd->msg->buf[pd->pos]; | |
300 | } | |
301 | } | |
302 | ||
303 | static int sh_mobile_i2c_isr_tx(struct sh_mobile_i2c_data *pd) | |
304 | { | |
305 | unsigned char data; | |
306 | ||
307 | if (pd->pos == pd->msg->len) | |
308 | return 1; | |
309 | ||
310 | sh_mobile_i2c_get_data(pd, &data); | |
311 | ||
312 | if (sh_mobile_i2c_is_last_byte(pd)) | |
313 | i2c_op(pd, OP_TX_STOP, data); | |
314 | else if (sh_mobile_i2c_is_first_byte(pd)) | |
315 | i2c_op(pd, OP_TX_FIRST, data); | |
316 | else | |
317 | i2c_op(pd, OP_TX, data); | |
318 | ||
319 | pd->pos++; | |
320 | return 0; | |
321 | } | |
322 | ||
323 | static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd) | |
324 | { | |
325 | unsigned char data; | |
326 | int real_pos; | |
327 | ||
328 | do { | |
329 | if (pd->pos <= -1) { | |
330 | sh_mobile_i2c_get_data(pd, &data); | |
331 | ||
332 | if (sh_mobile_i2c_is_first_byte(pd)) | |
333 | i2c_op(pd, OP_TX_FIRST, data); | |
334 | else | |
335 | i2c_op(pd, OP_TX, data); | |
336 | break; | |
337 | } | |
338 | ||
339 | if (pd->pos == 0) { | |
340 | i2c_op(pd, OP_TX_TO_RX, 0); | |
341 | break; | |
342 | } | |
343 | ||
344 | real_pos = pd->pos - 2; | |
345 | ||
346 | if (pd->pos == pd->msg->len) { | |
347 | if (real_pos < 0) { | |
348 | i2c_op(pd, OP_RX_STOP, 0); | |
349 | break; | |
350 | } | |
351 | data = i2c_op(pd, OP_RX_STOP_DATA, 0); | |
352 | } else | |
353 | data = i2c_op(pd, OP_RX, 0); | |
354 | ||
bff4056c MD |
355 | if (real_pos >= 0) |
356 | pd->msg->buf[real_pos] = data; | |
4eb00c9f MD |
357 | } while (0); |
358 | ||
359 | pd->pos++; | |
360 | return pd->pos == (pd->msg->len + 2); | |
361 | } | |
362 | ||
da672773 MD |
363 | static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id) |
364 | { | |
365 | struct platform_device *dev = dev_id; | |
366 | struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev); | |
4eb00c9f MD |
367 | unsigned char sr; |
368 | int wakeup; | |
da672773 MD |
369 | |
370 | sr = ioread8(ICSR(pd)); | |
4eb00c9f | 371 | pd->sr |= sr; /* remember state */ |
da672773 MD |
372 | |
373 | dev_dbg(pd->dev, "i2c_isr 0x%02x 0x%02x %s %d %d!\n", sr, pd->sr, | |
4eb00c9f MD |
374 | (pd->msg->flags & I2C_M_RD) ? "read" : "write", |
375 | pd->pos, pd->msg->len); | |
da672773 MD |
376 | |
377 | if (sr & (ICSR_AL | ICSR_TACK)) { | |
4eb00c9f MD |
378 | /* don't interrupt transaction - continue to issue stop */ |
379 | iowrite8(sr & ~(ICSR_AL | ICSR_TACK), ICSR(pd)); | |
380 | wakeup = 0; | |
381 | } else if (pd->msg->flags & I2C_M_RD) | |
382 | wakeup = sh_mobile_i2c_isr_rx(pd); | |
383 | else | |
384 | wakeup = sh_mobile_i2c_isr_tx(pd); | |
da672773 | 385 | |
4eb00c9f MD |
386 | if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */ |
387 | iowrite8(sr & ~ICSR_WAIT, ICSR(pd)); | |
da672773 | 388 | |
da672773 MD |
389 | if (wakeup) { |
390 | pd->sr |= SW_DONE; | |
391 | wake_up(&pd->wait); | |
392 | } | |
393 | ||
394 | return IRQ_HANDLED; | |
395 | } | |
396 | ||
397 | static int start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg) | |
398 | { | |
4eb00c9f MD |
399 | if (usr_msg->len == 0 && (usr_msg->flags & I2C_M_RD)) { |
400 | dev_err(pd->dev, "Unsupported zero length i2c read\n"); | |
401 | return -EIO; | |
402 | } | |
403 | ||
da672773 MD |
404 | /* Initialize channel registers */ |
405 | iowrite8(ioread8(ICCR(pd)) & ~ICCR_ICE, ICCR(pd)); | |
406 | ||
407 | /* Enable channel and configure rx ack */ | |
408 | iowrite8(ioread8(ICCR(pd)) | ICCR_ICE, ICCR(pd)); | |
409 | ||
410 | /* Set the clock */ | |
411 | iowrite8(pd->iccl, ICCL(pd)); | |
412 | iowrite8(pd->icch, ICCH(pd)); | |
413 | ||
414 | pd->msg = usr_msg; | |
415 | pd->pos = -1; | |
416 | pd->sr = 0; | |
417 | ||
4eb00c9f MD |
418 | /* Enable all interrupts to begin with */ |
419 | iowrite8(ICIC_WAITE | ICIC_ALE | ICIC_TACKE | ICIC_DTEE, ICIC(pd)); | |
da672773 MD |
420 | return 0; |
421 | } | |
422 | ||
423 | static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter, | |
424 | struct i2c_msg *msgs, | |
425 | int num) | |
426 | { | |
427 | struct sh_mobile_i2c_data *pd = i2c_get_adapdata(adapter); | |
428 | struct i2c_msg *msg; | |
429 | int err = 0; | |
430 | u_int8_t val; | |
431 | int i, k, retry_count; | |
432 | ||
433 | activate_ch(pd); | |
434 | ||
435 | /* Process all messages */ | |
436 | for (i = 0; i < num; i++) { | |
437 | msg = &msgs[i]; | |
438 | ||
439 | err = start_ch(pd, msg); | |
440 | if (err) | |
441 | break; | |
442 | ||
443 | i2c_op(pd, OP_START, 0); | |
444 | ||
445 | /* The interrupt handler takes care of the rest... */ | |
446 | k = wait_event_timeout(pd->wait, | |
447 | pd->sr & (ICSR_TACK | SW_DONE), | |
448 | 5 * HZ); | |
449 | if (!k) | |
450 | dev_err(pd->dev, "Transfer request timed out\n"); | |
451 | ||
4eb00c9f | 452 | retry_count = 1000; |
da672773 MD |
453 | again: |
454 | val = ioread8(ICSR(pd)); | |
455 | ||
456 | dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr); | |
457 | ||
da672773 MD |
458 | /* the interrupt handler may wake us up before the |
459 | * transfer is finished, so poll the hardware | |
460 | * until we're done. | |
461 | */ | |
4eb00c9f MD |
462 | if (val & ICSR_BUSY) { |
463 | udelay(10); | |
da672773 MD |
464 | if (retry_count--) |
465 | goto again; | |
466 | ||
467 | err = -EIO; | |
468 | dev_err(pd->dev, "Polling timed out\n"); | |
469 | break; | |
470 | } | |
4eb00c9f MD |
471 | |
472 | /* handle missing acknowledge and arbitration lost */ | |
473 | if ((val | pd->sr) & (ICSR_TACK | ICSR_AL)) { | |
474 | err = -EIO; | |
475 | break; | |
476 | } | |
da672773 MD |
477 | } |
478 | ||
479 | deactivate_ch(pd); | |
480 | ||
481 | if (!err) | |
482 | err = num; | |
483 | return err; | |
484 | } | |
485 | ||
486 | static u32 sh_mobile_i2c_func(struct i2c_adapter *adapter) | |
487 | { | |
488 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; | |
489 | } | |
490 | ||
491 | static struct i2c_algorithm sh_mobile_i2c_algorithm = { | |
492 | .functionality = sh_mobile_i2c_func, | |
493 | .master_xfer = sh_mobile_i2c_xfer, | |
494 | }; | |
495 | ||
da672773 MD |
496 | static int sh_mobile_i2c_hook_irqs(struct platform_device *dev, int hook) |
497 | { | |
498 | struct resource *res; | |
499 | int ret = -ENXIO; | |
500 | int q, m; | |
501 | int k = 0; | |
502 | int n = 0; | |
503 | ||
504 | while ((res = platform_get_resource(dev, IORESOURCE_IRQ, k))) { | |
505 | for (n = res->start; hook && n <= res->end; n++) { | |
506 | if (request_irq(n, sh_mobile_i2c_isr, IRQF_DISABLED, | |
22e965c2 | 507 | dev_name(&dev->dev), dev)) |
da672773 MD |
508 | goto rollback; |
509 | } | |
510 | k++; | |
511 | } | |
512 | ||
513 | if (hook) | |
514 | return k > 0 ? 0 : -ENOENT; | |
515 | ||
516 | k--; | |
517 | ret = 0; | |
518 | ||
519 | rollback: | |
520 | for (q = k; k >= 0; k--) { | |
521 | for (m = n; m >= res->start; m--) | |
522 | free_irq(m, dev); | |
523 | ||
524 | res = platform_get_resource(dev, IORESOURCE_IRQ, k - 1); | |
525 | m = res->end; | |
526 | } | |
527 | ||
528 | return ret; | |
529 | } | |
530 | ||
531 | static int sh_mobile_i2c_probe(struct platform_device *dev) | |
532 | { | |
533 | struct sh_mobile_i2c_data *pd; | |
534 | struct i2c_adapter *adap; | |
535 | struct resource *res; | |
a5616bd0 | 536 | char clk_name[8]; |
da672773 MD |
537 | int size; |
538 | int ret; | |
539 | ||
540 | pd = kzalloc(sizeof(struct sh_mobile_i2c_data), GFP_KERNEL); | |
541 | if (pd == NULL) { | |
542 | dev_err(&dev->dev, "cannot allocate private data\n"); | |
543 | return -ENOMEM; | |
544 | } | |
545 | ||
a5616bd0 MD |
546 | snprintf(clk_name, sizeof(clk_name), "i2c%d", dev->id); |
547 | pd->clk = clk_get(&dev->dev, clk_name); | |
da672773 | 548 | if (IS_ERR(pd->clk)) { |
a5616bd0 | 549 | dev_err(&dev->dev, "cannot get clock \"%s\"\n", clk_name); |
da672773 MD |
550 | ret = PTR_ERR(pd->clk); |
551 | goto err; | |
552 | } | |
553 | ||
554 | ret = sh_mobile_i2c_hook_irqs(dev, 1); | |
555 | if (ret) { | |
556 | dev_err(&dev->dev, "cannot request IRQ\n"); | |
557 | goto err_clk; | |
558 | } | |
559 | ||
560 | pd->dev = &dev->dev; | |
561 | platform_set_drvdata(dev, pd); | |
562 | ||
563 | res = platform_get_resource(dev, IORESOURCE_MEM, 0); | |
564 | if (res == NULL) { | |
565 | dev_err(&dev->dev, "cannot find IO resource\n"); | |
566 | ret = -ENOENT; | |
567 | goto err_irq; | |
568 | } | |
569 | ||
59330825 | 570 | size = resource_size(res); |
da672773 MD |
571 | |
572 | pd->reg = ioremap(res->start, size); | |
573 | if (pd->reg == NULL) { | |
574 | dev_err(&dev->dev, "cannot map IO\n"); | |
575 | ret = -ENXIO; | |
576 | goto err_irq; | |
577 | } | |
578 | ||
f1a3b994 MD |
579 | /* Enable Runtime PM for this device. |
580 | * | |
581 | * Also tell the Runtime PM core to ignore children | |
582 | * for this device since it is valid for us to suspend | |
583 | * this I2C master driver even though the slave devices | |
584 | * on the I2C bus may not be suspended. | |
585 | * | |
586 | * The state of the I2C hardware bus is unaffected by | |
587 | * the Runtime PM state. | |
588 | */ | |
589 | pm_suspend_ignore_children(&dev->dev, true); | |
590 | pm_runtime_enable(&dev->dev); | |
591 | ||
da672773 MD |
592 | /* setup the private data */ |
593 | adap = &pd->adap; | |
594 | i2c_set_adapdata(adap, pd); | |
595 | ||
596 | adap->owner = THIS_MODULE; | |
597 | adap->algo = &sh_mobile_i2c_algorithm; | |
598 | adap->dev.parent = &dev->dev; | |
599 | adap->retries = 5; | |
600 | adap->nr = dev->id; | |
601 | ||
602 | strlcpy(adap->name, dev->name, sizeof(adap->name)); | |
603 | ||
a5616bd0 MD |
604 | spin_lock_init(&pd->lock); |
605 | init_waitqueue_head(&pd->wait); | |
da672773 MD |
606 | |
607 | ret = i2c_add_numbered_adapter(adap); | |
608 | if (ret < 0) { | |
609 | dev_err(&dev->dev, "cannot add numbered adapter\n"); | |
610 | goto err_all; | |
611 | } | |
612 | ||
613 | return 0; | |
614 | ||
615 | err_all: | |
616 | iounmap(pd->reg); | |
617 | err_irq: | |
618 | sh_mobile_i2c_hook_irqs(dev, 0); | |
619 | err_clk: | |
620 | clk_put(pd->clk); | |
621 | err: | |
622 | kfree(pd); | |
623 | return ret; | |
624 | } | |
625 | ||
626 | static int sh_mobile_i2c_remove(struct platform_device *dev) | |
627 | { | |
628 | struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev); | |
629 | ||
630 | i2c_del_adapter(&pd->adap); | |
631 | iounmap(pd->reg); | |
632 | sh_mobile_i2c_hook_irqs(dev, 0); | |
633 | clk_put(pd->clk); | |
f1a3b994 | 634 | pm_runtime_disable(&dev->dev); |
da672773 MD |
635 | kfree(pd); |
636 | return 0; | |
637 | } | |
638 | ||
f1a3b994 MD |
639 | static int sh_mobile_i2c_runtime_nop(struct device *dev) |
640 | { | |
641 | /* Runtime PM callback shared between ->runtime_suspend() | |
642 | * and ->runtime_resume(). Simply returns success. | |
643 | * | |
644 | * This driver re-initializes all registers after | |
645 | * pm_runtime_get_sync() anyway so there is no need | |
646 | * to save and restore registers here. | |
647 | */ | |
648 | return 0; | |
649 | } | |
650 | ||
47145210 | 651 | static const struct dev_pm_ops sh_mobile_i2c_dev_pm_ops = { |
f1a3b994 MD |
652 | .runtime_suspend = sh_mobile_i2c_runtime_nop, |
653 | .runtime_resume = sh_mobile_i2c_runtime_nop, | |
654 | }; | |
655 | ||
da672773 MD |
656 | static struct platform_driver sh_mobile_i2c_driver = { |
657 | .driver = { | |
658 | .name = "i2c-sh_mobile", | |
659 | .owner = THIS_MODULE, | |
f1a3b994 | 660 | .pm = &sh_mobile_i2c_dev_pm_ops, |
da672773 MD |
661 | }, |
662 | .probe = sh_mobile_i2c_probe, | |
663 | .remove = sh_mobile_i2c_remove, | |
664 | }; | |
665 | ||
666 | static int __init sh_mobile_i2c_adap_init(void) | |
667 | { | |
668 | return platform_driver_register(&sh_mobile_i2c_driver); | |
669 | } | |
670 | ||
671 | static void __exit sh_mobile_i2c_adap_exit(void) | |
672 | { | |
673 | platform_driver_unregister(&sh_mobile_i2c_driver); | |
674 | } | |
675 | ||
ccb3bc16 | 676 | subsys_initcall(sh_mobile_i2c_adap_init); |
da672773 MD |
677 | module_exit(sh_mobile_i2c_adap_exit); |
678 | ||
679 | MODULE_DESCRIPTION("SuperH Mobile I2C Bus Controller driver"); | |
680 | MODULE_AUTHOR("Magnus Damm"); | |
681 | MODULE_LICENSE("GPL v2"); |