Commit | Line | Data |
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9f2bc79f MC |
1 | /* |
2 | * drivers/w1/masters/omap_hdq.c | |
3 | * | |
c354a864 | 4 | * Copyright (C) 2007,2012 Texas Instruments, Inc. |
9f2bc79f MC |
5 | * |
6 | * This file is licensed under the terms of the GNU General Public License | |
7 | * version 2. This program is licensed "as is" without any warranty of any | |
8 | * kind, whether express or implied. | |
9 | * | |
10 | */ | |
11 | #include <linux/kernel.h> | |
12 | #include <linux/module.h> | |
13 | #include <linux/platform_device.h> | |
14 | #include <linux/interrupt.h> | |
5a0e3ad6 | 15 | #include <linux/slab.h> |
9f2bc79f | 16 | #include <linux/err.h> |
9f2bc79f | 17 | #include <linux/io.h> |
81fa08f2 | 18 | #include <linux/sched.h> |
c354a864 | 19 | #include <linux/pm_runtime.h> |
e93762bb | 20 | #include <linux/of.h> |
9f2bc79f | 21 | |
de0d6dbd | 22 | #include <linux/w1.h> |
9f2bc79f MC |
23 | |
24 | #define MOD_NAME "OMAP_HDQ:" | |
25 | ||
26 | #define OMAP_HDQ_REVISION 0x00 | |
27 | #define OMAP_HDQ_TX_DATA 0x04 | |
28 | #define OMAP_HDQ_RX_DATA 0x08 | |
29 | #define OMAP_HDQ_CTRL_STATUS 0x0c | |
e93762bb V |
30 | #define OMAP_HDQ_CTRL_STATUS_SINGLE BIT(7) |
31 | #define OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK BIT(6) | |
32 | #define OMAP_HDQ_CTRL_STATUS_CLOCKENABLE BIT(5) | |
33 | #define OMAP_HDQ_CTRL_STATUS_GO BIT(4) | |
34 | #define OMAP_HDQ_CTRL_STATUS_PRESENCE BIT(3) | |
35 | #define OMAP_HDQ_CTRL_STATUS_INITIALIZATION BIT(2) | |
36 | #define OMAP_HDQ_CTRL_STATUS_DIR BIT(1) | |
9f2bc79f | 37 | #define OMAP_HDQ_INT_STATUS 0x10 |
e93762bb V |
38 | #define OMAP_HDQ_INT_STATUS_TXCOMPLETE BIT(2) |
39 | #define OMAP_HDQ_INT_STATUS_RXCOMPLETE BIT(1) | |
40 | #define OMAP_HDQ_INT_STATUS_TIMEOUT BIT(0) | |
9f2bc79f | 41 | #define OMAP_HDQ_SYSCONFIG 0x14 |
e93762bb V |
42 | #define OMAP_HDQ_SYSCONFIG_SOFTRESET BIT(1) |
43 | #define OMAP_HDQ_SYSCONFIG_AUTOIDLE BIT(0) | |
44 | #define OMAP_HDQ_SYSCONFIG_NOIDLE 0x0 | |
9f2bc79f | 45 | #define OMAP_HDQ_SYSSTATUS 0x18 |
e93762bb | 46 | #define OMAP_HDQ_SYSSTATUS_RESETDONE BIT(0) |
9f2bc79f MC |
47 | |
48 | #define OMAP_HDQ_FLAG_CLEAR 0 | |
49 | #define OMAP_HDQ_FLAG_SET 1 | |
50 | #define OMAP_HDQ_TIMEOUT (HZ/5) | |
51 | ||
52 | #define OMAP_HDQ_MAX_USER 4 | |
53 | ||
54 | static DECLARE_WAIT_QUEUE_HEAD(hdq_wait_queue); | |
50fa2951 | 55 | |
9f2bc79f | 56 | static int w1_id; |
50fa2951 AD |
57 | module_param(w1_id, int, S_IRUSR); |
58 | MODULE_PARM_DESC(w1_id, "1-wire id for the slave detection in HDQ mode"); | |
9f2bc79f MC |
59 | |
60 | struct hdq_data { | |
61 | struct device *dev; | |
62 | void __iomem *hdq_base; | |
63 | /* lock status update */ | |
64 | struct mutex hdq_mutex; | |
65 | int hdq_usecount; | |
9f2bc79f MC |
66 | u8 hdq_irqstatus; |
67 | /* device lock */ | |
68 | spinlock_t hdq_spinlock; | |
69 | /* | |
70 | * Used to control the call to omap_hdq_get and omap_hdq_put. | |
71 | * HDQ Protocol: Write the CMD|REG_address first, followed by | |
72 | * the data wrire or read. | |
73 | */ | |
74 | int init_trans; | |
e93762bb V |
75 | int rrw; |
76 | /* mode: 0-HDQ 1-W1 */ | |
77 | int mode; | |
78 | ||
9f2bc79f MC |
79 | }; |
80 | ||
9f2bc79f MC |
81 | /* HDQ register I/O routines */ |
82 | static inline u8 hdq_reg_in(struct hdq_data *hdq_data, u32 offset) | |
83 | { | |
2acd0894 | 84 | return __raw_readl(hdq_data->hdq_base + offset); |
9f2bc79f MC |
85 | } |
86 | ||
87 | static inline void hdq_reg_out(struct hdq_data *hdq_data, u32 offset, u8 val) | |
88 | { | |
2acd0894 | 89 | __raw_writel(val, hdq_data->hdq_base + offset); |
9f2bc79f MC |
90 | } |
91 | ||
92 | static inline u8 hdq_reg_merge(struct hdq_data *hdq_data, u32 offset, | |
93 | u8 val, u8 mask) | |
94 | { | |
2acd0894 | 95 | u8 new_val = (__raw_readl(hdq_data->hdq_base + offset) & ~mask) |
9f2bc79f | 96 | | (val & mask); |
2acd0894 | 97 | __raw_writel(new_val, hdq_data->hdq_base + offset); |
9f2bc79f MC |
98 | |
99 | return new_val; | |
100 | } | |
101 | ||
e93762bb V |
102 | static void hdq_disable_interrupt(struct hdq_data *hdq_data, u32 offset, |
103 | u32 mask) | |
104 | { | |
105 | u32 ie; | |
106 | ||
107 | ie = readl(hdq_data->hdq_base + offset); | |
108 | writel(ie & mask, hdq_data->hdq_base + offset); | |
109 | } | |
110 | ||
9f2bc79f MC |
111 | /* |
112 | * Wait for one or more bits in flag change. | |
113 | * HDQ_FLAG_SET: wait until any bit in the flag is set. | |
114 | * HDQ_FLAG_CLEAR: wait until all bits in the flag are cleared. | |
115 | * return 0 on success and -ETIMEDOUT in the case of timeout. | |
116 | */ | |
117 | static int hdq_wait_for_flag(struct hdq_data *hdq_data, u32 offset, | |
118 | u8 flag, u8 flag_set, u8 *status) | |
119 | { | |
120 | int ret = 0; | |
121 | unsigned long timeout = jiffies + OMAP_HDQ_TIMEOUT; | |
122 | ||
123 | if (flag_set == OMAP_HDQ_FLAG_CLEAR) { | |
124 | /* wait for the flag clear */ | |
125 | while (((*status = hdq_reg_in(hdq_data, offset)) & flag) | |
126 | && time_before(jiffies, timeout)) { | |
127 | schedule_timeout_uninterruptible(1); | |
128 | } | |
129 | if (*status & flag) | |
130 | ret = -ETIMEDOUT; | |
131 | } else if (flag_set == OMAP_HDQ_FLAG_SET) { | |
132 | /* wait for the flag set */ | |
133 | while (!((*status = hdq_reg_in(hdq_data, offset)) & flag) | |
134 | && time_before(jiffies, timeout)) { | |
135 | schedule_timeout_uninterruptible(1); | |
136 | } | |
137 | if (!(*status & flag)) | |
138 | ret = -ETIMEDOUT; | |
139 | } else | |
140 | return -EINVAL; | |
141 | ||
142 | return ret; | |
143 | } | |
144 | ||
145 | /* write out a byte and fill *status with HDQ_INT_STATUS */ | |
146 | static int hdq_write_byte(struct hdq_data *hdq_data, u8 val, u8 *status) | |
147 | { | |
148 | int ret; | |
149 | u8 tmp_status; | |
150 | unsigned long irqflags; | |
151 | ||
152 | *status = 0; | |
153 | ||
154 | spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags); | |
155 | /* clear interrupt flags via a dummy read */ | |
156 | hdq_reg_in(hdq_data, OMAP_HDQ_INT_STATUS); | |
157 | /* ISR loads it with new INT_STATUS */ | |
158 | hdq_data->hdq_irqstatus = 0; | |
159 | spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags); | |
160 | ||
161 | hdq_reg_out(hdq_data, OMAP_HDQ_TX_DATA, val); | |
162 | ||
163 | /* set the GO bit */ | |
164 | hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_GO, | |
165 | OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO); | |
166 | /* wait for the TXCOMPLETE bit */ | |
167 | ret = wait_event_timeout(hdq_wait_queue, | |
168 | hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT); | |
169 | if (ret == 0) { | |
170 | dev_dbg(hdq_data->dev, "TX wait elapsed\n"); | |
7b5362a6 | 171 | ret = -ETIMEDOUT; |
9f2bc79f MC |
172 | goto out; |
173 | } | |
174 | ||
175 | *status = hdq_data->hdq_irqstatus; | |
176 | /* check irqstatus */ | |
177 | if (!(*status & OMAP_HDQ_INT_STATUS_TXCOMPLETE)) { | |
178 | dev_dbg(hdq_data->dev, "timeout waiting for" | |
7b5362a6 | 179 | " TXCOMPLETE/RXCOMPLETE, %x", *status); |
9f2bc79f MC |
180 | ret = -ETIMEDOUT; |
181 | goto out; | |
182 | } | |
183 | ||
184 | /* wait for the GO bit return to zero */ | |
185 | ret = hdq_wait_for_flag(hdq_data, OMAP_HDQ_CTRL_STATUS, | |
186 | OMAP_HDQ_CTRL_STATUS_GO, | |
187 | OMAP_HDQ_FLAG_CLEAR, &tmp_status); | |
188 | if (ret) { | |
189 | dev_dbg(hdq_data->dev, "timeout waiting GO bit" | |
7b5362a6 | 190 | " return to zero, %x", tmp_status); |
9f2bc79f MC |
191 | } |
192 | ||
193 | out: | |
194 | return ret; | |
195 | } | |
196 | ||
197 | /* HDQ Interrupt service routine */ | |
198 | static irqreturn_t hdq_isr(int irq, void *_hdq) | |
199 | { | |
200 | struct hdq_data *hdq_data = _hdq; | |
201 | unsigned long irqflags; | |
202 | ||
203 | spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags); | |
204 | hdq_data->hdq_irqstatus = hdq_reg_in(hdq_data, OMAP_HDQ_INT_STATUS); | |
205 | spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags); | |
206 | dev_dbg(hdq_data->dev, "hdq_isr: %x", hdq_data->hdq_irqstatus); | |
207 | ||
208 | if (hdq_data->hdq_irqstatus & | |
209 | (OMAP_HDQ_INT_STATUS_TXCOMPLETE | OMAP_HDQ_INT_STATUS_RXCOMPLETE | |
210 | | OMAP_HDQ_INT_STATUS_TIMEOUT)) { | |
211 | /* wake up sleeping process */ | |
212 | wake_up(&hdq_wait_queue); | |
213 | } | |
214 | ||
215 | return IRQ_HANDLED; | |
216 | } | |
217 | ||
e93762bb | 218 | /* W1 search callback function in HDQ mode */ |
06b0d4dc SM |
219 | static void omap_w1_search_bus(void *_hdq, struct w1_master *master_dev, |
220 | u8 search_type, w1_slave_found_callback slave_found) | |
9f2bc79f MC |
221 | { |
222 | u64 module_id, rn_le, cs, id; | |
223 | ||
224 | if (w1_id) | |
225 | module_id = w1_id; | |
226 | else | |
227 | module_id = 0x1; | |
228 | ||
229 | rn_le = cpu_to_le64(module_id); | |
230 | /* | |
231 | * HDQ might not obey truly the 1-wire spec. | |
232 | * So calculate CRC based on module parameter. | |
233 | */ | |
234 | cs = w1_calc_crc8((u8 *)&rn_le, 7); | |
235 | id = (cs << 56) | module_id; | |
236 | ||
06b0d4dc | 237 | slave_found(master_dev, id); |
9f2bc79f MC |
238 | } |
239 | ||
240 | static int _omap_hdq_reset(struct hdq_data *hdq_data) | |
241 | { | |
242 | int ret; | |
243 | u8 tmp_status; | |
244 | ||
e93762bb V |
245 | hdq_reg_out(hdq_data, OMAP_HDQ_SYSCONFIG, |
246 | OMAP_HDQ_SYSCONFIG_SOFTRESET); | |
9f2bc79f | 247 | /* |
e93762bb | 248 | * Select HDQ/1W mode & enable clocks. |
9f2bc79f MC |
249 | * It is observed that INT flags can't be cleared via a read and GO/INIT |
250 | * won't return to zero if interrupt is disabled. So we always enable | |
251 | * interrupt. | |
252 | */ | |
253 | hdq_reg_out(hdq_data, OMAP_HDQ_CTRL_STATUS, | |
254 | OMAP_HDQ_CTRL_STATUS_CLOCKENABLE | | |
255 | OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK); | |
256 | ||
257 | /* wait for reset to complete */ | |
258 | ret = hdq_wait_for_flag(hdq_data, OMAP_HDQ_SYSSTATUS, | |
259 | OMAP_HDQ_SYSSTATUS_RESETDONE, OMAP_HDQ_FLAG_SET, &tmp_status); | |
260 | if (ret) | |
261 | dev_dbg(hdq_data->dev, "timeout waiting HDQ reset, %x", | |
262 | tmp_status); | |
263 | else { | |
264 | hdq_reg_out(hdq_data, OMAP_HDQ_CTRL_STATUS, | |
265 | OMAP_HDQ_CTRL_STATUS_CLOCKENABLE | | |
e93762bb V |
266 | OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK | |
267 | hdq_data->mode); | |
9f2bc79f MC |
268 | hdq_reg_out(hdq_data, OMAP_HDQ_SYSCONFIG, |
269 | OMAP_HDQ_SYSCONFIG_AUTOIDLE); | |
270 | } | |
271 | ||
272 | return ret; | |
273 | } | |
274 | ||
275 | /* Issue break pulse to the device */ | |
276 | static int omap_hdq_break(struct hdq_data *hdq_data) | |
277 | { | |
278 | int ret = 0; | |
279 | u8 tmp_status; | |
280 | unsigned long irqflags; | |
281 | ||
282 | ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); | |
283 | if (ret < 0) { | |
284 | dev_dbg(hdq_data->dev, "Could not acquire mutex\n"); | |
285 | ret = -EINTR; | |
286 | goto rtn; | |
287 | } | |
288 | ||
289 | spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags); | |
290 | /* clear interrupt flags via a dummy read */ | |
291 | hdq_reg_in(hdq_data, OMAP_HDQ_INT_STATUS); | |
292 | /* ISR loads it with new INT_STATUS */ | |
293 | hdq_data->hdq_irqstatus = 0; | |
294 | spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags); | |
295 | ||
296 | /* set the INIT and GO bit */ | |
297 | hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS, | |
298 | OMAP_HDQ_CTRL_STATUS_INITIALIZATION | OMAP_HDQ_CTRL_STATUS_GO, | |
299 | OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_INITIALIZATION | | |
300 | OMAP_HDQ_CTRL_STATUS_GO); | |
301 | ||
302 | /* wait for the TIMEOUT bit */ | |
303 | ret = wait_event_timeout(hdq_wait_queue, | |
304 | hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT); | |
305 | if (ret == 0) { | |
306 | dev_dbg(hdq_data->dev, "break wait elapsed\n"); | |
307 | ret = -EINTR; | |
308 | goto out; | |
309 | } | |
310 | ||
311 | tmp_status = hdq_data->hdq_irqstatus; | |
312 | /* check irqstatus */ | |
313 | if (!(tmp_status & OMAP_HDQ_INT_STATUS_TIMEOUT)) { | |
314 | dev_dbg(hdq_data->dev, "timeout waiting for TIMEOUT, %x", | |
315 | tmp_status); | |
316 | ret = -ETIMEDOUT; | |
317 | goto out; | |
318 | } | |
e93762bb V |
319 | |
320 | /* | |
321 | * check for the presence detect bit to get | |
322 | * set to show that the slave is responding | |
323 | */ | |
324 | if (!(hdq_reg_in(hdq_data, OMAP_HDQ_CTRL_STATUS) & | |
325 | OMAP_HDQ_CTRL_STATUS_PRESENCE)) { | |
326 | dev_dbg(hdq_data->dev, "Presence bit not set\n"); | |
327 | ret = -ETIMEDOUT; | |
328 | goto out; | |
329 | } | |
330 | ||
9f2bc79f MC |
331 | /* |
332 | * wait for both INIT and GO bits rerurn to zero. | |
333 | * zero wait time expected for interrupt mode. | |
334 | */ | |
335 | ret = hdq_wait_for_flag(hdq_data, OMAP_HDQ_CTRL_STATUS, | |
336 | OMAP_HDQ_CTRL_STATUS_INITIALIZATION | | |
337 | OMAP_HDQ_CTRL_STATUS_GO, OMAP_HDQ_FLAG_CLEAR, | |
338 | &tmp_status); | |
339 | if (ret) | |
340 | dev_dbg(hdq_data->dev, "timeout waiting INIT&GO bits" | |
7b5362a6 | 341 | " return to zero, %x", tmp_status); |
9f2bc79f MC |
342 | |
343 | out: | |
344 | mutex_unlock(&hdq_data->hdq_mutex); | |
345 | rtn: | |
346 | return ret; | |
347 | } | |
348 | ||
349 | static int hdq_read_byte(struct hdq_data *hdq_data, u8 *val) | |
350 | { | |
351 | int ret = 0; | |
352 | u8 status; | |
9f2bc79f MC |
353 | |
354 | ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); | |
355 | if (ret < 0) { | |
356 | ret = -EINTR; | |
357 | goto rtn; | |
358 | } | |
359 | ||
360 | if (!hdq_data->hdq_usecount) { | |
361 | ret = -EINVAL; | |
362 | goto out; | |
363 | } | |
364 | ||
365 | if (!(hdq_data->hdq_irqstatus & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) { | |
366 | hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS, | |
367 | OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO, | |
368 | OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO); | |
369 | /* | |
b7e938d0 | 370 | * The RX comes immediately after TX. |
9f2bc79f | 371 | */ |
b7e938d0 N |
372 | wait_event_timeout(hdq_wait_queue, |
373 | (hdq_data->hdq_irqstatus | |
374 | & OMAP_HDQ_INT_STATUS_RXCOMPLETE), | |
375 | OMAP_HDQ_TIMEOUT); | |
376 | ||
9f2bc79f MC |
377 | hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS, 0, |
378 | OMAP_HDQ_CTRL_STATUS_DIR); | |
379 | status = hdq_data->hdq_irqstatus; | |
380 | /* check irqstatus */ | |
381 | if (!(status & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) { | |
382 | dev_dbg(hdq_data->dev, "timeout waiting for" | |
7b5362a6 | 383 | " RXCOMPLETE, %x", status); |
9f2bc79f MC |
384 | ret = -ETIMEDOUT; |
385 | goto out; | |
386 | } | |
387 | } | |
388 | /* the data is ready. Read it in! */ | |
389 | *val = hdq_reg_in(hdq_data, OMAP_HDQ_RX_DATA); | |
390 | out: | |
391 | mutex_unlock(&hdq_data->hdq_mutex); | |
392 | rtn: | |
7b5362a6 | 393 | return ret; |
9f2bc79f MC |
394 | |
395 | } | |
396 | ||
e93762bb | 397 | /* Enable clocks and set the controller to HDQ/1W mode */ |
9f2bc79f MC |
398 | static int omap_hdq_get(struct hdq_data *hdq_data) |
399 | { | |
400 | int ret = 0; | |
401 | ||
402 | ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); | |
403 | if (ret < 0) { | |
404 | ret = -EINTR; | |
405 | goto rtn; | |
406 | } | |
407 | ||
408 | if (OMAP_HDQ_MAX_USER == hdq_data->hdq_usecount) { | |
409 | dev_dbg(hdq_data->dev, "attempt to exceed the max use count"); | |
410 | ret = -EINVAL; | |
411 | goto out; | |
412 | } else { | |
413 | hdq_data->hdq_usecount++; | |
414 | try_module_get(THIS_MODULE); | |
415 | if (1 == hdq_data->hdq_usecount) { | |
c354a864 PW |
416 | |
417 | pm_runtime_get_sync(hdq_data->dev); | |
9f2bc79f | 418 | |
e93762bb | 419 | /* make sure HDQ/1W is out of reset */ |
9f2bc79f MC |
420 | if (!(hdq_reg_in(hdq_data, OMAP_HDQ_SYSSTATUS) & |
421 | OMAP_HDQ_SYSSTATUS_RESETDONE)) { | |
422 | ret = _omap_hdq_reset(hdq_data); | |
423 | if (ret) | |
424 | /* back up the count */ | |
425 | hdq_data->hdq_usecount--; | |
426 | } else { | |
e93762bb | 427 | /* select HDQ/1W mode & enable clocks */ |
9f2bc79f MC |
428 | hdq_reg_out(hdq_data, OMAP_HDQ_CTRL_STATUS, |
429 | OMAP_HDQ_CTRL_STATUS_CLOCKENABLE | | |
e93762bb V |
430 | OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK | |
431 | hdq_data->mode); | |
9f2bc79f | 432 | hdq_reg_out(hdq_data, OMAP_HDQ_SYSCONFIG, |
e93762bb | 433 | OMAP_HDQ_SYSCONFIG_NOIDLE); |
9f2bc79f MC |
434 | hdq_reg_in(hdq_data, OMAP_HDQ_INT_STATUS); |
435 | } | |
436 | } | |
437 | } | |
438 | ||
9f2bc79f MC |
439 | out: |
440 | mutex_unlock(&hdq_data->hdq_mutex); | |
441 | rtn: | |
442 | return ret; | |
443 | } | |
444 | ||
445 | /* Disable clocks to the module */ | |
446 | static int omap_hdq_put(struct hdq_data *hdq_data) | |
447 | { | |
448 | int ret = 0; | |
449 | ||
450 | ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); | |
451 | if (ret < 0) | |
452 | return -EINTR; | |
453 | ||
e93762bb V |
454 | hdq_reg_out(hdq_data, OMAP_HDQ_SYSCONFIG, |
455 | OMAP_HDQ_SYSCONFIG_AUTOIDLE); | |
9f2bc79f MC |
456 | if (0 == hdq_data->hdq_usecount) { |
457 | dev_dbg(hdq_data->dev, "attempt to decrement use count" | |
7b5362a6 | 458 | " when it is zero"); |
9f2bc79f MC |
459 | ret = -EINVAL; |
460 | } else { | |
461 | hdq_data->hdq_usecount--; | |
462 | module_put(THIS_MODULE); | |
c354a864 PW |
463 | if (0 == hdq_data->hdq_usecount) |
464 | pm_runtime_put_sync(hdq_data->dev); | |
9f2bc79f MC |
465 | } |
466 | mutex_unlock(&hdq_data->hdq_mutex); | |
467 | ||
468 | return ret; | |
469 | } | |
470 | ||
e93762bb V |
471 | /* |
472 | * W1 triplet callback function - used for searching ROM addresses. | |
473 | * Registered only when controller is in 1-wire mode. | |
474 | */ | |
475 | static u8 omap_w1_triplet(void *_hdq, u8 bdir) | |
476 | { | |
477 | u8 id_bit, comp_bit; | |
478 | int err; | |
479 | u8 ret = 0x3; /* no slaves responded */ | |
480 | struct hdq_data *hdq_data = _hdq; | |
481 | u8 ctrl = OMAP_HDQ_CTRL_STATUS_SINGLE | OMAP_HDQ_CTRL_STATUS_GO | | |
482 | OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK; | |
483 | u8 mask = ctrl | OMAP_HDQ_CTRL_STATUS_DIR; | |
484 | ||
485 | omap_hdq_get(_hdq); | |
486 | ||
487 | err = mutex_lock_interruptible(&hdq_data->hdq_mutex); | |
488 | if (err < 0) { | |
489 | dev_dbg(hdq_data->dev, "Could not acquire mutex\n"); | |
490 | goto rtn; | |
491 | } | |
492 | ||
493 | hdq_data->hdq_irqstatus = 0; | |
494 | /* read id_bit */ | |
495 | hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, | |
496 | ctrl | OMAP_HDQ_CTRL_STATUS_DIR, mask); | |
497 | err = wait_event_timeout(hdq_wait_queue, | |
498 | (hdq_data->hdq_irqstatus | |
499 | & OMAP_HDQ_INT_STATUS_RXCOMPLETE), | |
500 | OMAP_HDQ_TIMEOUT); | |
501 | if (err == 0) { | |
502 | dev_dbg(hdq_data->dev, "RX wait elapsed\n"); | |
503 | goto out; | |
504 | } | |
505 | id_bit = (hdq_reg_in(_hdq, OMAP_HDQ_RX_DATA) & 0x01); | |
506 | ||
507 | hdq_data->hdq_irqstatus = 0; | |
508 | /* read comp_bit */ | |
509 | hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, | |
510 | ctrl | OMAP_HDQ_CTRL_STATUS_DIR, mask); | |
511 | err = wait_event_timeout(hdq_wait_queue, | |
512 | (hdq_data->hdq_irqstatus | |
513 | & OMAP_HDQ_INT_STATUS_RXCOMPLETE), | |
514 | OMAP_HDQ_TIMEOUT); | |
515 | if (err == 0) { | |
516 | dev_dbg(hdq_data->dev, "RX wait elapsed\n"); | |
517 | goto out; | |
518 | } | |
519 | comp_bit = (hdq_reg_in(_hdq, OMAP_HDQ_RX_DATA) & 0x01); | |
520 | ||
521 | if (id_bit && comp_bit) { | |
522 | ret = 0x03; /* no slaves responded */ | |
523 | goto out; | |
524 | } | |
525 | if (!id_bit && !comp_bit) { | |
526 | /* Both bits are valid, take the direction given */ | |
527 | ret = bdir ? 0x04 : 0; | |
528 | } else { | |
529 | /* Only one bit is valid, take that direction */ | |
530 | bdir = id_bit; | |
531 | ret = id_bit ? 0x05 : 0x02; | |
532 | } | |
533 | ||
534 | /* write bdir bit */ | |
535 | hdq_reg_out(_hdq, OMAP_HDQ_TX_DATA, bdir); | |
536 | hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, ctrl, mask); | |
537 | err = wait_event_timeout(hdq_wait_queue, | |
538 | (hdq_data->hdq_irqstatus | |
539 | & OMAP_HDQ_INT_STATUS_TXCOMPLETE), | |
540 | OMAP_HDQ_TIMEOUT); | |
541 | if (err == 0) { | |
542 | dev_dbg(hdq_data->dev, "TX wait elapsed\n"); | |
543 | goto out; | |
544 | } | |
545 | ||
546 | hdq_reg_merge(_hdq, OMAP_HDQ_CTRL_STATUS, 0, | |
547 | OMAP_HDQ_CTRL_STATUS_SINGLE); | |
548 | ||
549 | out: | |
550 | mutex_unlock(&hdq_data->hdq_mutex); | |
551 | rtn: | |
552 | omap_hdq_put(_hdq); | |
553 | return ret; | |
554 | } | |
555 | ||
556 | /* reset callback */ | |
557 | static u8 omap_w1_reset_bus(void *_hdq) | |
558 | { | |
559 | omap_hdq_get(_hdq); | |
560 | omap_hdq_break(_hdq); | |
561 | omap_hdq_put(_hdq); | |
562 | return 0; | |
563 | } | |
564 | ||
9f2bc79f MC |
565 | /* Read a byte of data from the device */ |
566 | static u8 omap_w1_read_byte(void *_hdq) | |
567 | { | |
568 | struct hdq_data *hdq_data = _hdq; | |
569 | u8 val = 0; | |
570 | int ret; | |
571 | ||
e93762bb V |
572 | /* First write to initialize the transfer */ |
573 | if (hdq_data->init_trans == 0) | |
574 | omap_hdq_get(hdq_data); | |
575 | ||
9f2bc79f MC |
576 | ret = hdq_read_byte(hdq_data, &val); |
577 | if (ret) { | |
578 | ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); | |
579 | if (ret < 0) { | |
580 | dev_dbg(hdq_data->dev, "Could not acquire mutex\n"); | |
581 | return -EINTR; | |
582 | } | |
583 | hdq_data->init_trans = 0; | |
584 | mutex_unlock(&hdq_data->hdq_mutex); | |
585 | omap_hdq_put(hdq_data); | |
586 | return -1; | |
587 | } | |
588 | ||
e93762bb V |
589 | hdq_disable_interrupt(hdq_data, OMAP_HDQ_CTRL_STATUS, |
590 | ~OMAP_HDQ_CTRL_STATUS_INTERRUPTMASK); | |
e93762bb | 591 | |
9f2bc79f MC |
592 | /* Write followed by a read, release the module */ |
593 | if (hdq_data->init_trans) { | |
594 | ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); | |
595 | if (ret < 0) { | |
596 | dev_dbg(hdq_data->dev, "Could not acquire mutex\n"); | |
597 | return -EINTR; | |
598 | } | |
599 | hdq_data->init_trans = 0; | |
600 | mutex_unlock(&hdq_data->hdq_mutex); | |
601 | omap_hdq_put(hdq_data); | |
602 | } | |
603 | ||
604 | return val; | |
605 | } | |
606 | ||
607 | /* Write a byte of data to the device */ | |
608 | static void omap_w1_write_byte(void *_hdq, u8 byte) | |
609 | { | |
610 | struct hdq_data *hdq_data = _hdq; | |
611 | int ret; | |
612 | u8 status; | |
613 | ||
614 | /* First write to initialize the transfer */ | |
615 | if (hdq_data->init_trans == 0) | |
616 | omap_hdq_get(hdq_data); | |
617 | ||
e93762bb V |
618 | /* |
619 | * We need to reset the slave before | |
620 | * issuing the SKIP ROM command, else | |
621 | * the slave will not work. | |
622 | */ | |
623 | if (byte == W1_SKIP_ROM) | |
624 | omap_hdq_break(hdq_data); | |
625 | ||
9f2bc79f MC |
626 | ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); |
627 | if (ret < 0) { | |
628 | dev_dbg(hdq_data->dev, "Could not acquire mutex\n"); | |
629 | return; | |
630 | } | |
631 | hdq_data->init_trans++; | |
632 | mutex_unlock(&hdq_data->hdq_mutex); | |
633 | ||
634 | ret = hdq_write_byte(hdq_data, byte, &status); | |
7b5362a6 | 635 | if (ret < 0) { |
9f2bc79f MC |
636 | dev_dbg(hdq_data->dev, "TX failure:Ctrl status %x\n", status); |
637 | return; | |
638 | } | |
639 | ||
25985edc | 640 | /* Second write, data transferred. Release the module */ |
9f2bc79f MC |
641 | if (hdq_data->init_trans > 1) { |
642 | omap_hdq_put(hdq_data); | |
643 | ret = mutex_lock_interruptible(&hdq_data->hdq_mutex); | |
644 | if (ret < 0) { | |
645 | dev_dbg(hdq_data->dev, "Could not acquire mutex\n"); | |
646 | return; | |
647 | } | |
648 | hdq_data->init_trans = 0; | |
649 | mutex_unlock(&hdq_data->hdq_mutex); | |
650 | } | |
9f2bc79f MC |
651 | } |
652 | ||
50fa2951 AD |
653 | static struct w1_bus_master omap_w1_master = { |
654 | .read_byte = omap_w1_read_byte, | |
655 | .write_byte = omap_w1_write_byte, | |
656 | .reset_bus = omap_w1_reset_bus, | |
657 | }; | |
658 | ||
479e2bce | 659 | static int omap_hdq_probe(struct platform_device *pdev) |
9f2bc79f | 660 | { |
19afea50 | 661 | struct device *dev = &pdev->dev; |
9f2bc79f MC |
662 | struct hdq_data *hdq_data; |
663 | struct resource *res; | |
664 | int ret, irq; | |
665 | u8 rev; | |
e93762bb | 666 | const char *mode; |
9f2bc79f | 667 | |
19afea50 | 668 | hdq_data = devm_kzalloc(dev, sizeof(*hdq_data), GFP_KERNEL); |
9f2bc79f MC |
669 | if (!hdq_data) { |
670 | dev_dbg(&pdev->dev, "unable to allocate memory\n"); | |
19afea50 | 671 | return -ENOMEM; |
9f2bc79f MC |
672 | } |
673 | ||
19afea50 | 674 | hdq_data->dev = dev; |
9f2bc79f MC |
675 | platform_set_drvdata(pdev, hdq_data); |
676 | ||
677 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
4d6dc3a7 TR |
678 | hdq_data->hdq_base = devm_ioremap_resource(dev, res); |
679 | if (IS_ERR(hdq_data->hdq_base)) | |
680 | return PTR_ERR(hdq_data->hdq_base); | |
9f2bc79f | 681 | |
9f2bc79f | 682 | hdq_data->hdq_usecount = 0; |
e93762bb | 683 | hdq_data->rrw = 0; |
9f2bc79f MC |
684 | mutex_init(&hdq_data->hdq_mutex); |
685 | ||
c354a864 | 686 | pm_runtime_enable(&pdev->dev); |
e93762bb V |
687 | ret = pm_runtime_get_sync(&pdev->dev); |
688 | if (ret < 0) { | |
689 | dev_dbg(&pdev->dev, "pm_runtime_get_sync failed\n"); | |
690 | goto err_w1; | |
691 | } | |
692 | ||
693 | ret = _omap_hdq_reset(hdq_data); | |
694 | if (ret) { | |
695 | dev_dbg(&pdev->dev, "reset failed\n"); | |
8333eb15 | 696 | goto err_irq; |
e93762bb | 697 | } |
9f2bc79f MC |
698 | |
699 | rev = hdq_reg_in(hdq_data, OMAP_HDQ_REVISION); | |
700 | dev_info(&pdev->dev, "OMAP HDQ Hardware Rev %c.%c. Driver in %s mode\n", | |
701 | (rev >> 4) + '0', (rev & 0x0f) + '0', "Interrupt"); | |
702 | ||
703 | spin_lock_init(&hdq_data->hdq_spinlock); | |
704 | ||
705 | irq = platform_get_irq(pdev, 0); | |
706 | if (irq < 0) { | |
c89876dd GS |
707 | dev_dbg(&pdev->dev, "Failed to get IRQ: %d\n", irq); |
708 | ret = irq; | |
9f2bc79f MC |
709 | goto err_irq; |
710 | } | |
711 | ||
fe576a58 | 712 | ret = devm_request_irq(dev, irq, hdq_isr, 0, "omap_hdq", hdq_data); |
9f2bc79f MC |
713 | if (ret < 0) { |
714 | dev_dbg(&pdev->dev, "could not request irq\n"); | |
715 | goto err_irq; | |
716 | } | |
717 | ||
718 | omap_hdq_break(hdq_data); | |
719 | ||
c354a864 | 720 | pm_runtime_put_sync(&pdev->dev); |
9f2bc79f | 721 | |
e93762bb V |
722 | ret = of_property_read_string(pdev->dev.of_node, "ti,mode", &mode); |
723 | if (ret < 0 || !strcmp(mode, "hdq")) { | |
724 | hdq_data->mode = 0; | |
725 | omap_w1_master.search = omap_w1_search_bus; | |
726 | } else { | |
727 | hdq_data->mode = 1; | |
728 | omap_w1_master.triplet = omap_w1_triplet; | |
729 | } | |
730 | ||
9f2bc79f MC |
731 | omap_w1_master.data = hdq_data; |
732 | ||
733 | ret = w1_add_master_device(&omap_w1_master); | |
734 | if (ret) { | |
735 | dev_dbg(&pdev->dev, "Failure in registering w1 master\n"); | |
736 | goto err_w1; | |
737 | } | |
738 | ||
739 | return 0; | |
740 | ||
9f2bc79f | 741 | err_irq: |
c354a864 PW |
742 | pm_runtime_put_sync(&pdev->dev); |
743 | err_w1: | |
744 | pm_runtime_disable(&pdev->dev); | |
80d02d27 | 745 | |
9f2bc79f | 746 | return ret; |
9f2bc79f MC |
747 | } |
748 | ||
82849a93 | 749 | static int omap_hdq_remove(struct platform_device *pdev) |
9f2bc79f MC |
750 | { |
751 | struct hdq_data *hdq_data = platform_get_drvdata(pdev); | |
752 | ||
753 | mutex_lock(&hdq_data->hdq_mutex); | |
754 | ||
755 | if (hdq_data->hdq_usecount) { | |
756 | dev_dbg(&pdev->dev, "removed when use count is not zero\n"); | |
2020002a | 757 | mutex_unlock(&hdq_data->hdq_mutex); |
9f2bc79f MC |
758 | return -EBUSY; |
759 | } | |
760 | ||
761 | mutex_unlock(&hdq_data->hdq_mutex); | |
762 | ||
763 | /* remove module dependency */ | |
c354a864 | 764 | pm_runtime_disable(&pdev->dev); |
9f2bc79f MC |
765 | |
766 | return 0; | |
767 | } | |
768 | ||
50fa2951 AD |
769 | static const struct of_device_id omap_hdq_dt_ids[] = { |
770 | { .compatible = "ti,omap3-1w" }, | |
771 | { .compatible = "ti,am4372-hdq" }, | |
772 | {} | |
773 | }; | |
774 | MODULE_DEVICE_TABLE(of, omap_hdq_dt_ids); | |
9f2bc79f | 775 | |
50fa2951 AD |
776 | static struct platform_driver omap_hdq_driver = { |
777 | .probe = omap_hdq_probe, | |
778 | .remove = omap_hdq_remove, | |
779 | .driver = { | |
780 | .name = "omap_hdq", | |
781 | .of_match_table = omap_hdq_dt_ids, | |
782 | }, | |
783 | }; | |
784 | module_platform_driver(omap_hdq_driver); | |
9f2bc79f MC |
785 | |
786 | MODULE_AUTHOR("Texas Instruments"); | |
e93762bb | 787 | MODULE_DESCRIPTION("HDQ-1W driver Library"); |
9f2bc79f | 788 | MODULE_LICENSE("GPL"); |