diff options
author | Bryan Wu <bryan.wu@analog.com> | 2007-05-01 17:26:32 -0400 |
---|---|---|
committer | Jean Delvare <khali@hyperion.delvare> | 2007-05-01 17:26:32 -0400 |
commit | d24ecfcc3953f9c3b833508cd839be614a3f3c64 (patch) | |
tree | 9f2d66e87fa295166fad628b694858f8e318a2a7 /drivers/i2c/busses/i2c-bfin-twi.c | |
parent | 6edac5803fb66f514d454d8e45595a170f04ea0e (diff) |
i2c: Blackfin Two Wire Interface driver
The i2c linux driver for blackfin architecture which supports blackfin
on-chip TWI controller i2c operation.
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
Reviewed-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'drivers/i2c/busses/i2c-bfin-twi.c')
-rw-r--r-- | drivers/i2c/busses/i2c-bfin-twi.c | 644 |
1 files changed, 644 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c new file mode 100644 index 000000000000..6311039dfe60 --- /dev/null +++ b/drivers/i2c/busses/i2c-bfin-twi.c | |||
@@ -0,0 +1,644 @@ | |||
1 | /* | ||
2 | * drivers/i2c/busses/i2c-bfin-twi.c | ||
3 | * | ||
4 | * Description: Driver for Blackfin Two Wire Interface | ||
5 | * | ||
6 | * Author: sonicz <sonic.zhang@analog.com> | ||
7 | * | ||
8 | * Copyright (c) 2005-2007 Analog Devices, Inc. | ||
9 | * | ||
10 | * This program is free software; you can redistribute it and/or modify | ||
11 | * it under the terms of the GNU General Public License as published by | ||
12 | * the Free Software Foundation; either version 2 of the License, or | ||
13 | * (at your option) any later version. | ||
14 | * | ||
15 | * This program is distributed in the hope that it will be useful, | ||
16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
18 | * GNU General Public License for more details. | ||
19 | * | ||
20 | * You should have received a copy of the GNU General Public License | ||
21 | * along with this program; if not, write to the Free Software | ||
22 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
23 | */ | ||
24 | |||
25 | #include <linux/module.h> | ||
26 | #include <linux/kernel.h> | ||
27 | #include <linux/init.h> | ||
28 | #include <linux/i2c.h> | ||
29 | #include <linux/mm.h> | ||
30 | #include <linux/timer.h> | ||
31 | #include <linux/spinlock.h> | ||
32 | #include <linux/completion.h> | ||
33 | #include <linux/interrupt.h> | ||
34 | #include <linux/platform_device.h> | ||
35 | |||
36 | #include <asm/blackfin.h> | ||
37 | #include <asm/irq.h> | ||
38 | |||
39 | #define POLL_TIMEOUT (2 * HZ) | ||
40 | |||
41 | /* SMBus mode*/ | ||
42 | #define TWI_I2C_MODE_STANDARD 0x01 | ||
43 | #define TWI_I2C_MODE_STANDARDSUB 0x02 | ||
44 | #define TWI_I2C_MODE_COMBINED 0x04 | ||
45 | |||
46 | struct bfin_twi_iface { | ||
47 | struct mutex twi_lock; | ||
48 | int irq; | ||
49 | spinlock_t lock; | ||
50 | char read_write; | ||
51 | u8 command; | ||
52 | u8 *transPtr; | ||
53 | int readNum; | ||
54 | int writeNum; | ||
55 | int cur_mode; | ||
56 | int manual_stop; | ||
57 | int result; | ||
58 | int timeout_count; | ||
59 | struct timer_list timeout_timer; | ||
60 | struct i2c_adapter adap; | ||
61 | struct completion complete; | ||
62 | }; | ||
63 | |||
64 | static struct bfin_twi_iface twi_iface; | ||
65 | |||
66 | static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface) | ||
67 | { | ||
68 | unsigned short twi_int_status = bfin_read_TWI_INT_STAT(); | ||
69 | unsigned short mast_stat = bfin_read_TWI_MASTER_STAT(); | ||
70 | |||
71 | if (twi_int_status & XMTSERV) { | ||
72 | /* Transmit next data */ | ||
73 | if (iface->writeNum > 0) { | ||
74 | bfin_write_TWI_XMT_DATA8(*(iface->transPtr++)); | ||
75 | iface->writeNum--; | ||
76 | } | ||
77 | /* start receive immediately after complete sending in | ||
78 | * combine mode. | ||
79 | */ | ||
80 | else if (iface->cur_mode == TWI_I2C_MODE_COMBINED) { | ||
81 | bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | ||
82 | | MDIR | RSTART); | ||
83 | } else if (iface->manual_stop) | ||
84 | bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | ||
85 | | STOP); | ||
86 | SSYNC(); | ||
87 | /* Clear status */ | ||
88 | bfin_write_TWI_INT_STAT(XMTSERV); | ||
89 | SSYNC(); | ||
90 | } | ||
91 | if (twi_int_status & RCVSERV) { | ||
92 | if (iface->readNum > 0) { | ||
93 | /* Receive next data */ | ||
94 | *(iface->transPtr) = bfin_read_TWI_RCV_DATA8(); | ||
95 | if (iface->cur_mode == TWI_I2C_MODE_COMBINED) { | ||
96 | /* Change combine mode into sub mode after | ||
97 | * read first data. | ||
98 | */ | ||
99 | iface->cur_mode = TWI_I2C_MODE_STANDARDSUB; | ||
100 | /* Get read number from first byte in block | ||
101 | * combine mode. | ||
102 | */ | ||
103 | if (iface->readNum == 1 && iface->manual_stop) | ||
104 | iface->readNum = *iface->transPtr + 1; | ||
105 | } | ||
106 | iface->transPtr++; | ||
107 | iface->readNum--; | ||
108 | } else if (iface->manual_stop) { | ||
109 | bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | ||
110 | | STOP); | ||
111 | SSYNC(); | ||
112 | } | ||
113 | /* Clear interrupt source */ | ||
114 | bfin_write_TWI_INT_STAT(RCVSERV); | ||
115 | SSYNC(); | ||
116 | } | ||
117 | if (twi_int_status & MERR) { | ||
118 | bfin_write_TWI_INT_STAT(MERR); | ||
119 | bfin_write_TWI_INT_MASK(0); | ||
120 | bfin_write_TWI_MASTER_STAT(0x3e); | ||
121 | bfin_write_TWI_MASTER_CTL(0); | ||
122 | SSYNC(); | ||
123 | iface->result = -1; | ||
124 | /* if both err and complete int stats are set, return proper | ||
125 | * results. | ||
126 | */ | ||
127 | if (twi_int_status & MCOMP) { | ||
128 | bfin_write_TWI_INT_STAT(MCOMP); | ||
129 | bfin_write_TWI_INT_MASK(0); | ||
130 | bfin_write_TWI_MASTER_CTL(0); | ||
131 | SSYNC(); | ||
132 | /* If it is a quick transfer, only address bug no data, | ||
133 | * not an err, return 1. | ||
134 | */ | ||
135 | if (iface->writeNum == 0 && (mast_stat & BUFRDERR)) | ||
136 | iface->result = 1; | ||
137 | /* If address not acknowledged return -1, | ||
138 | * else return 0. | ||
139 | */ | ||
140 | else if (!(mast_stat & ANAK)) | ||
141 | iface->result = 0; | ||
142 | } | ||
143 | complete(&iface->complete); | ||
144 | return; | ||
145 | } | ||
146 | if (twi_int_status & MCOMP) { | ||
147 | bfin_write_TWI_INT_STAT(MCOMP); | ||
148 | SSYNC(); | ||
149 | if (iface->cur_mode == TWI_I2C_MODE_COMBINED) { | ||
150 | if (iface->readNum == 0) { | ||
151 | /* set the read number to 1 and ask for manual | ||
152 | * stop in block combine mode | ||
153 | */ | ||
154 | iface->readNum = 1; | ||
155 | iface->manual_stop = 1; | ||
156 | bfin_write_TWI_MASTER_CTL( | ||
157 | bfin_read_TWI_MASTER_CTL() | ||
158 | | (0xff << 6)); | ||
159 | } else { | ||
160 | /* set the readd number in other | ||
161 | * combine mode. | ||
162 | */ | ||
163 | bfin_write_TWI_MASTER_CTL( | ||
164 | (bfin_read_TWI_MASTER_CTL() & | ||
165 | (~(0xff << 6))) | | ||
166 | ( iface->readNum << 6)); | ||
167 | } | ||
168 | /* remove restart bit and enable master receive */ | ||
169 | bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() & | ||
170 | ~RSTART); | ||
171 | bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | | ||
172 | MEN | MDIR); | ||
173 | SSYNC(); | ||
174 | } else { | ||
175 | iface->result = 1; | ||
176 | bfin_write_TWI_INT_MASK(0); | ||
177 | bfin_write_TWI_MASTER_CTL(0); | ||
178 | SSYNC(); | ||
179 | complete(&iface->complete); | ||
180 | } | ||
181 | } | ||
182 | } | ||
183 | |||
184 | /* Interrupt handler */ | ||
185 | static irqreturn_t bfin_twi_interrupt_entry(int irq, void *dev_id) | ||
186 | { | ||
187 | struct bfin_twi_iface *iface = dev_id; | ||
188 | unsigned long flags; | ||
189 | |||
190 | spin_lock_irqsave(&iface->lock, flags); | ||
191 | del_timer(&iface->timeout_timer); | ||
192 | bfin_twi_handle_interrupt(iface); | ||
193 | spin_unlock_irqrestore(&iface->lock, flags); | ||
194 | return IRQ_HANDLED; | ||
195 | } | ||
196 | |||
197 | static void bfin_twi_timeout(unsigned long data) | ||
198 | { | ||
199 | struct bfin_twi_iface *iface = (struct bfin_twi_iface *)data; | ||
200 | unsigned long flags; | ||
201 | |||
202 | spin_lock_irqsave(&iface->lock, flags); | ||
203 | bfin_twi_handle_interrupt(iface); | ||
204 | if (iface->result == 0) { | ||
205 | iface->timeout_count--; | ||
206 | if (iface->timeout_count > 0) { | ||
207 | iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; | ||
208 | add_timer(&iface->timeout_timer); | ||
209 | } else { | ||
210 | iface->result = -1; | ||
211 | complete(&iface->complete); | ||
212 | } | ||
213 | } | ||
214 | spin_unlock_irqrestore(&iface->lock, flags); | ||
215 | } | ||
216 | |||
217 | /* | ||
218 | * Generic i2c master transfer entrypoint | ||
219 | */ | ||
220 | static int bfin_twi_master_xfer(struct i2c_adapter *adap, | ||
221 | struct i2c_msg *msgs, int num) | ||
222 | { | ||
223 | struct bfin_twi_iface *iface = adap->algo_data; | ||
224 | struct i2c_msg *pmsg; | ||
225 | int i, ret; | ||
226 | int rc = 0; | ||
227 | |||
228 | if (!(bfin_read_TWI_CONTROL() & TWI_ENA)) | ||
229 | return -ENXIO; | ||
230 | |||
231 | mutex_lock(&iface->twi_lock); | ||
232 | |||
233 | while (bfin_read_TWI_MASTER_STAT() & BUSBUSY) { | ||
234 | mutex_unlock(&iface->twi_lock); | ||
235 | yield(); | ||
236 | mutex_lock(&iface->twi_lock); | ||
237 | } | ||
238 | |||
239 | ret = 0; | ||
240 | for (i = 0; rc >= 0 && i < num; i++) { | ||
241 | pmsg = &msgs[i]; | ||
242 | if (pmsg->flags & I2C_M_TEN) { | ||
243 | dev_err(&(adap->dev), "i2c-bfin-twi: 10 bits addr " | ||
244 | "not supported !\n"); | ||
245 | rc = -EINVAL; | ||
246 | break; | ||
247 | } | ||
248 | |||
249 | iface->cur_mode = TWI_I2C_MODE_STANDARD; | ||
250 | iface->manual_stop = 0; | ||
251 | iface->transPtr = pmsg->buf; | ||
252 | iface->writeNum = iface->readNum = pmsg->len; | ||
253 | iface->result = 0; | ||
254 | iface->timeout_count = 10; | ||
255 | /* Set Transmit device address */ | ||
256 | bfin_write_TWI_MASTER_ADDR(pmsg->addr); | ||
257 | |||
258 | /* FIFO Initiation. Data in FIFO should be | ||
259 | * discarded before start a new operation. | ||
260 | */ | ||
261 | bfin_write_TWI_FIFO_CTL(0x3); | ||
262 | SSYNC(); | ||
263 | bfin_write_TWI_FIFO_CTL(0); | ||
264 | SSYNC(); | ||
265 | |||
266 | if (pmsg->flags & I2C_M_RD) | ||
267 | iface->read_write = I2C_SMBUS_READ; | ||
268 | else { | ||
269 | iface->read_write = I2C_SMBUS_WRITE; | ||
270 | /* Transmit first data */ | ||
271 | if (iface->writeNum > 0) { | ||
272 | bfin_write_TWI_XMT_DATA8(*(iface->transPtr++)); | ||
273 | iface->writeNum--; | ||
274 | SSYNC(); | ||
275 | } | ||
276 | } | ||
277 | |||
278 | /* clear int stat */ | ||
279 | bfin_write_TWI_INT_STAT(MERR|MCOMP|XMTSERV|RCVSERV); | ||
280 | |||
281 | /* Interrupt mask . Enable XMT, RCV interrupt */ | ||
282 | bfin_write_TWI_INT_MASK(MCOMP | MERR | | ||
283 | ((iface->read_write == I2C_SMBUS_READ)? | ||
284 | RCVSERV : XMTSERV)); | ||
285 | SSYNC(); | ||
286 | |||
287 | if (pmsg->len > 0 && pmsg->len <= 255) | ||
288 | bfin_write_TWI_MASTER_CTL(pmsg->len << 6); | ||
289 | else if (pmsg->len > 255) { | ||
290 | bfin_write_TWI_MASTER_CTL(0xff << 6); | ||
291 | iface->manual_stop = 1; | ||
292 | } else | ||
293 | break; | ||
294 | |||
295 | iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; | ||
296 | add_timer(&iface->timeout_timer); | ||
297 | |||
298 | /* Master enable */ | ||
299 | bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | MEN | | ||
300 | ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) | | ||
301 | ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0)); | ||
302 | SSYNC(); | ||
303 | |||
304 | wait_for_completion(&iface->complete); | ||
305 | |||
306 | rc = iface->result; | ||
307 | if (rc == 1) | ||
308 | ret++; | ||
309 | else if (rc == -1) | ||
310 | break; | ||
311 | } | ||
312 | |||
313 | /* Release mutex */ | ||
314 | mutex_unlock(&iface->twi_lock); | ||
315 | |||
316 | return ret; | ||
317 | } | ||
318 | |||
319 | /* | ||
320 | * SMBus type transfer entrypoint | ||
321 | */ | ||
322 | |||
323 | int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr, | ||
324 | unsigned short flags, char read_write, | ||
325 | u8 command, int size, union i2c_smbus_data *data) | ||
326 | { | ||
327 | struct bfin_twi_iface *iface = adap->algo_data; | ||
328 | int rc = 0; | ||
329 | |||
330 | if (!(bfin_read_TWI_CONTROL() & TWI_ENA)) | ||
331 | return -ENXIO; | ||
332 | |||
333 | mutex_lock(&iface->twi_lock); | ||
334 | |||
335 | while (bfin_read_TWI_MASTER_STAT() & BUSBUSY) { | ||
336 | mutex_unlock(&iface->twi_lock); | ||
337 | yield(); | ||
338 | mutex_lock(&iface->twi_lock); | ||
339 | } | ||
340 | |||
341 | iface->writeNum = 0; | ||
342 | iface->readNum = 0; | ||
343 | |||
344 | /* Prepare datas & select mode */ | ||
345 | switch (size) { | ||
346 | case I2C_SMBUS_QUICK: | ||
347 | iface->transPtr = NULL; | ||
348 | iface->cur_mode = TWI_I2C_MODE_STANDARD; | ||
349 | break; | ||
350 | case I2C_SMBUS_BYTE: | ||
351 | if (data == NULL) | ||
352 | iface->transPtr = NULL; | ||
353 | else { | ||
354 | if (read_write == I2C_SMBUS_READ) | ||
355 | iface->readNum = 1; | ||
356 | else | ||
357 | iface->writeNum = 1; | ||
358 | iface->transPtr = &data->byte; | ||
359 | } | ||
360 | iface->cur_mode = TWI_I2C_MODE_STANDARD; | ||
361 | break; | ||
362 | case I2C_SMBUS_BYTE_DATA: | ||
363 | if (read_write == I2C_SMBUS_READ) { | ||
364 | iface->readNum = 1; | ||
365 | iface->cur_mode = TWI_I2C_MODE_COMBINED; | ||
366 | } else { | ||
367 | iface->writeNum = 1; | ||
368 | iface->cur_mode = TWI_I2C_MODE_STANDARDSUB; | ||
369 | } | ||
370 | iface->transPtr = &data->byte; | ||
371 | break; | ||
372 | case I2C_SMBUS_WORD_DATA: | ||
373 | if (read_write == I2C_SMBUS_READ) { | ||
374 | iface->readNum = 2; | ||
375 | iface->cur_mode = TWI_I2C_MODE_COMBINED; | ||
376 | } else { | ||
377 | iface->writeNum = 2; | ||
378 | iface->cur_mode = TWI_I2C_MODE_STANDARDSUB; | ||
379 | } | ||
380 | iface->transPtr = (u8 *)&data->word; | ||
381 | break; | ||
382 | case I2C_SMBUS_PROC_CALL: | ||
383 | iface->writeNum = 2; | ||
384 | iface->readNum = 2; | ||
385 | iface->cur_mode = TWI_I2C_MODE_COMBINED; | ||
386 | iface->transPtr = (u8 *)&data->word; | ||
387 | break; | ||
388 | case I2C_SMBUS_BLOCK_DATA: | ||
389 | if (read_write == I2C_SMBUS_READ) { | ||
390 | iface->readNum = 0; | ||
391 | iface->cur_mode = TWI_I2C_MODE_COMBINED; | ||
392 | } else { | ||
393 | iface->writeNum = data->block[0] + 1; | ||
394 | iface->cur_mode = TWI_I2C_MODE_STANDARDSUB; | ||
395 | } | ||
396 | iface->transPtr = data->block; | ||
397 | break; | ||
398 | default: | ||
399 | return -1; | ||
400 | } | ||
401 | |||
402 | iface->result = 0; | ||
403 | iface->manual_stop = 0; | ||
404 | iface->read_write = read_write; | ||
405 | iface->command = command; | ||
406 | iface->timeout_count = 10; | ||
407 | |||
408 | /* FIFO Initiation. Data in FIFO should be discarded before | ||
409 | * start a new operation. | ||
410 | */ | ||
411 | bfin_write_TWI_FIFO_CTL(0x3); | ||
412 | SSYNC(); | ||
413 | bfin_write_TWI_FIFO_CTL(0); | ||
414 | |||
415 | /* clear int stat */ | ||
416 | bfin_write_TWI_INT_STAT(MERR|MCOMP|XMTSERV|RCVSERV); | ||
417 | |||
418 | /* Set Transmit device address */ | ||
419 | bfin_write_TWI_MASTER_ADDR(addr); | ||
420 | SSYNC(); | ||
421 | |||
422 | iface->timeout_timer.expires = jiffies + POLL_TIMEOUT; | ||
423 | add_timer(&iface->timeout_timer); | ||
424 | |||
425 | switch (iface->cur_mode) { | ||
426 | case TWI_I2C_MODE_STANDARDSUB: | ||
427 | bfin_write_TWI_XMT_DATA8(iface->command); | ||
428 | bfin_write_TWI_INT_MASK(MCOMP | MERR | | ||
429 | ((iface->read_write == I2C_SMBUS_READ) ? | ||
430 | RCVSERV : XMTSERV)); | ||
431 | SSYNC(); | ||
432 | |||
433 | if (iface->writeNum + 1 <= 255) | ||
434 | bfin_write_TWI_MASTER_CTL((iface->writeNum + 1) << 6); | ||
435 | else { | ||
436 | bfin_write_TWI_MASTER_CTL(0xff << 6); | ||
437 | iface->manual_stop = 1; | ||
438 | } | ||
439 | /* Master enable */ | ||
440 | bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | MEN | | ||
441 | ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0)); | ||
442 | break; | ||
443 | case TWI_I2C_MODE_COMBINED: | ||
444 | bfin_write_TWI_XMT_DATA8(iface->command); | ||
445 | bfin_write_TWI_INT_MASK(MCOMP | MERR | RCVSERV | XMTSERV); | ||
446 | SSYNC(); | ||
447 | |||
448 | if (iface->writeNum > 0) | ||
449 | bfin_write_TWI_MASTER_CTL((iface->writeNum + 1) << 6); | ||
450 | else | ||
451 | bfin_write_TWI_MASTER_CTL(0x1 << 6); | ||
452 | /* Master enable */ | ||
453 | bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | MEN | | ||
454 | ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ>100) ? FAST : 0)); | ||
455 | break; | ||
456 | default: | ||
457 | bfin_write_TWI_MASTER_CTL(0); | ||
458 | if (size != I2C_SMBUS_QUICK) { | ||
459 | /* Don't access xmit data register when this is a | ||
460 | * read operation. | ||
461 | */ | ||
462 | if (iface->read_write != I2C_SMBUS_READ) { | ||
463 | if (iface->writeNum > 0) { | ||
464 | bfin_write_TWI_XMT_DATA8(*(iface->transPtr++)); | ||
465 | if (iface->writeNum <= 255) | ||
466 | bfin_write_TWI_MASTER_CTL(iface->writeNum << 6); | ||
467 | else { | ||
468 | bfin_write_TWI_MASTER_CTL(0xff << 6); | ||
469 | iface->manual_stop = 1; | ||
470 | } | ||
471 | iface->writeNum--; | ||
472 | } else { | ||
473 | bfin_write_TWI_XMT_DATA8(iface->command); | ||
474 | bfin_write_TWI_MASTER_CTL(1 << 6); | ||
475 | } | ||
476 | } else { | ||
477 | if (iface->readNum > 0 && iface->readNum <= 255) | ||
478 | bfin_write_TWI_MASTER_CTL(iface->readNum << 6); | ||
479 | else if (iface->readNum > 255) { | ||
480 | bfin_write_TWI_MASTER_CTL(0xff << 6); | ||
481 | iface->manual_stop = 1; | ||
482 | } else { | ||
483 | del_timer(&iface->timeout_timer); | ||
484 | break; | ||
485 | } | ||
486 | } | ||
487 | } | ||
488 | bfin_write_TWI_INT_MASK(MCOMP | MERR | | ||
489 | ((iface->read_write == I2C_SMBUS_READ) ? | ||
490 | RCVSERV : XMTSERV)); | ||
491 | SSYNC(); | ||
492 | |||
493 | /* Master enable */ | ||
494 | bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | MEN | | ||
495 | ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) | | ||
496 | ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0)); | ||
497 | break; | ||
498 | } | ||
499 | SSYNC(); | ||
500 | |||
501 | wait_for_completion(&iface->complete); | ||
502 | |||
503 | rc = (iface->result >= 0) ? 0 : -1; | ||
504 | |||
505 | /* Release mutex */ | ||
506 | mutex_unlock(&iface->twi_lock); | ||
507 | |||
508 | return rc; | ||
509 | } | ||
510 | |||
511 | /* | ||
512 | * Return what the adapter supports | ||
513 | */ | ||
514 | static u32 bfin_twi_functionality(struct i2c_adapter *adap) | ||
515 | { | ||
516 | return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | | ||
517 | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | | ||
518 | I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_PROC_CALL | | ||
519 | I2C_FUNC_I2C; | ||
520 | } | ||
521 | |||
522 | |||
523 | static struct i2c_algorithm bfin_twi_algorithm = { | ||
524 | .master_xfer = bfin_twi_master_xfer, | ||
525 | .smbus_xfer = bfin_twi_smbus_xfer, | ||
526 | .functionality = bfin_twi_functionality, | ||
527 | }; | ||
528 | |||
529 | |||
530 | static int i2c_bfin_twi_suspend(struct platform_device *dev, pm_message_t state) | ||
531 | { | ||
532 | /* struct bfin_twi_iface *iface = platform_get_drvdata(dev);*/ | ||
533 | |||
534 | /* Disable TWI */ | ||
535 | bfin_write_TWI_CONTROL(bfin_read_TWI_CONTROL() & ~TWI_ENA); | ||
536 | SSYNC(); | ||
537 | |||
538 | return 0; | ||
539 | } | ||
540 | |||
541 | static int i2c_bfin_twi_resume(struct platform_device *dev) | ||
542 | { | ||
543 | /* struct bfin_twi_iface *iface = platform_get_drvdata(dev);*/ | ||
544 | |||
545 | /* Enable TWI */ | ||
546 | bfin_write_TWI_CONTROL(bfin_read_TWI_CONTROL() | TWI_ENA); | ||
547 | SSYNC(); | ||
548 | |||
549 | return 0; | ||
550 | } | ||
551 | |||
552 | static int i2c_bfin_twi_probe(struct platform_device *dev) | ||
553 | { | ||
554 | struct bfin_twi_iface *iface = &twi_iface; | ||
555 | struct i2c_adapter *p_adap; | ||
556 | int rc; | ||
557 | |||
558 | mutex_init(&(iface->twi_lock)); | ||
559 | spin_lock_init(&(iface->lock)); | ||
560 | init_completion(&(iface->complete)); | ||
561 | iface->irq = IRQ_TWI; | ||
562 | |||
563 | init_timer(&(iface->timeout_timer)); | ||
564 | iface->timeout_timer.function = bfin_twi_timeout; | ||
565 | iface->timeout_timer.data = (unsigned long)iface; | ||
566 | |||
567 | p_adap = &iface->adap; | ||
568 | p_adap->id = I2C_HW_BLACKFIN; | ||
569 | strlcpy(p_adap->name, dev->name, sizeof(p_adap->name)); | ||
570 | p_adap->algo = &bfin_twi_algorithm; | ||
571 | p_adap->algo_data = iface; | ||
572 | p_adap->class = I2C_CLASS_ALL; | ||
573 | p_adap->dev.parent = &dev->dev; | ||
574 | |||
575 | rc = request_irq(iface->irq, bfin_twi_interrupt_entry, | ||
576 | IRQF_DISABLED, dev->name, iface); | ||
577 | if (rc) { | ||
578 | dev_err(&(p_adap->dev), "i2c-bfin-twi: can't get IRQ %d !\n", | ||
579 | iface->irq); | ||
580 | return -ENODEV; | ||
581 | } | ||
582 | |||
583 | /* Set TWI internal clock as 10MHz */ | ||
584 | bfin_write_TWI_CONTROL(((get_sclk() / 1024 / 1024 + 5) / 10) & 0x7F); | ||
585 | |||
586 | /* Set Twi interface clock as specified */ | ||
587 | bfin_write_TWI_CLKDIV((( 5*1024 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ ) | ||
588 | << 8) | (( 5*1024 / CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ ) | ||
589 | & 0xFF)); | ||
590 | |||
591 | /* Enable TWI */ | ||
592 | bfin_write_TWI_CONTROL(bfin_read_TWI_CONTROL() | TWI_ENA); | ||
593 | SSYNC(); | ||
594 | |||
595 | rc = i2c_add_adapter(p_adap); | ||
596 | if (rc < 0) | ||
597 | free_irq(iface->irq, iface); | ||
598 | else | ||
599 | platform_set_drvdata(dev, iface); | ||
600 | |||
601 | return rc; | ||
602 | } | ||
603 | |||
604 | static int i2c_bfin_twi_remove(struct platform_device *pdev) | ||
605 | { | ||
606 | struct bfin_twi_iface *iface = platform_get_drvdata(pdev); | ||
607 | |||
608 | platform_set_drvdata(pdev, NULL); | ||
609 | |||
610 | i2c_del_adapter(&(iface->adap)); | ||
611 | free_irq(iface->irq, iface); | ||
612 | |||
613 | return 0; | ||
614 | } | ||
615 | |||
616 | static struct platform_driver i2c_bfin_twi_driver = { | ||
617 | .probe = i2c_bfin_twi_probe, | ||
618 | .remove = i2c_bfin_twi_remove, | ||
619 | .suspend = i2c_bfin_twi_suspend, | ||
620 | .resume = i2c_bfin_twi_resume, | ||
621 | .driver = { | ||
622 | .name = "i2c-bfin-twi", | ||
623 | .owner = THIS_MODULE, | ||
624 | }, | ||
625 | }; | ||
626 | |||
627 | static int __init i2c_bfin_twi_init(void) | ||
628 | { | ||
629 | pr_info("I2C: Blackfin I2C TWI driver\n"); | ||
630 | |||
631 | return platform_driver_register(&i2c_bfin_twi_driver); | ||
632 | } | ||
633 | |||
634 | static void __exit i2c_bfin_twi_exit(void) | ||
635 | { | ||
636 | platform_driver_unregister(&i2c_bfin_twi_driver); | ||
637 | } | ||
638 | |||
639 | MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>"); | ||
640 | MODULE_DESCRIPTION("I2C-Bus adapter routines for Blackfin TWI"); | ||
641 | MODULE_LICENSE("GPL"); | ||
642 | |||
643 | module_init(i2c_bfin_twi_init); | ||
644 | module_exit(i2c_bfin_twi_exit); | ||