diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-03-12 19:00:54 -0500 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-03-12 19:00:54 -0500 |
commit | dca1d9f6d7ae428c193f32bd3e9a4ca13176648b (patch) | |
tree | 02de8c3503c1c811754423d2fa3f3b4978044f6e /arch/arm/plat-samsung/adc.c | |
parent | 9ff99339447de403a46be5e3f23d0c794d540b06 (diff) | |
parent | 91e013827c0bcbb187ecf02213c5446b6f62d445 (diff) |
Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (370 commits)
ARM: S3C2443: Add set_rate and round_rate calls for armdiv clock
ARM: S3C2443: Remove #if 0 for clk_mpll
ARM: S3C2443: Update notes on MPLLREF clock
ARM: S3C2443: Further clksrc-clk conversions
ARM: S3C2443: Change to using plat-samsung clksrc-clk implementation
USB: Fix s3c-hsotg build following Samsung platform header moves
ARM: S3C64XX: Reintroduce unconditional build of audio device
ARM: 5961/1: ux500: fix CLKRST addresses
ARM: 5977/1: arm: Enable backtrace printing on oops when PC is corrupted
ASoC: Fix S3C64xx IIS driver for Samsung header reorg
ARM: S3C2440: Fix plat-s3c24xx move of s3c2440/s3c2442 support
[ARM] pxa: fix typo in mxm8x10.h
[ARM] pxa/raumfeld: set GPIO drive bits for LED pins
[ARM] pxa/zeus: Add support for mcp2515 CAN bus
[ARM] pxa/zeus: Add support for onboard max6369 watchdog
[ARM] pxa/zeus: Add Eurotech as the manufacturer
[ARM] pxa/zeus: Correct the USB host initialisation flags
[ARM] pxa/zeus: Allow usage of 8250-compatible UART in uncompress
[ARM] pxa: refactor uncompress.h for non-PXA uarts
[ARM] mmp2: fix incorrect calling of chip->mask_ack() for 2nd level cascaded IRQs
...
Diffstat (limited to 'arch/arm/plat-samsung/adc.c')
-rw-r--r-- | arch/arm/plat-samsung/adc.c | 474 |
1 files changed, 474 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/adc.c b/arch/arm/plat-samsung/adc.c new file mode 100644 index 000000000000..0b5833b9ac5b --- /dev/null +++ b/arch/arm/plat-samsung/adc.c | |||
@@ -0,0 +1,474 @@ | |||
1 | /* arch/arm/plat-samsung/adc.c | ||
2 | * | ||
3 | * Copyright (c) 2008 Simtec Electronics | ||
4 | * http://armlinux.simtec.co.uk/ | ||
5 | * Ben Dooks <ben@simtec.co.uk>, <ben-linux@fluff.org> | ||
6 | * | ||
7 | * Samsung ADC device core | ||
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 | |||
14 | #include <linux/module.h> | ||
15 | #include <linux/kernel.h> | ||
16 | #include <linux/platform_device.h> | ||
17 | #include <linux/sched.h> | ||
18 | #include <linux/list.h> | ||
19 | #include <linux/err.h> | ||
20 | #include <linux/clk.h> | ||
21 | #include <linux/interrupt.h> | ||
22 | #include <linux/io.h> | ||
23 | |||
24 | #include <plat/regs-adc.h> | ||
25 | #include <plat/adc.h> | ||
26 | |||
27 | /* This driver is designed to control the usage of the ADC block between | ||
28 | * the touchscreen and any other drivers that may need to use it, such as | ||
29 | * the hwmon driver. | ||
30 | * | ||
31 | * Priority will be given to the touchscreen driver, but as this itself is | ||
32 | * rate limited it should not starve other requests which are processed in | ||
33 | * order that they are received. | ||
34 | * | ||
35 | * Each user registers to get a client block which uniquely identifies it | ||
36 | * and stores information such as the necessary functions to callback when | ||
37 | * action is required. | ||
38 | */ | ||
39 | |||
40 | enum s3c_cpu_type { | ||
41 | TYPE_S3C24XX, | ||
42 | TYPE_S3C64XX | ||
43 | }; | ||
44 | |||
45 | struct s3c_adc_client { | ||
46 | struct platform_device *pdev; | ||
47 | struct list_head pend; | ||
48 | wait_queue_head_t *wait; | ||
49 | |||
50 | unsigned int nr_samples; | ||
51 | int result; | ||
52 | unsigned char is_ts; | ||
53 | unsigned char channel; | ||
54 | |||
55 | void (*select_cb)(struct s3c_adc_client *c, unsigned selected); | ||
56 | void (*convert_cb)(struct s3c_adc_client *c, | ||
57 | unsigned val1, unsigned val2, | ||
58 | unsigned *samples_left); | ||
59 | }; | ||
60 | |||
61 | struct adc_device { | ||
62 | struct platform_device *pdev; | ||
63 | struct platform_device *owner; | ||
64 | struct clk *clk; | ||
65 | struct s3c_adc_client *cur; | ||
66 | struct s3c_adc_client *ts_pend; | ||
67 | void __iomem *regs; | ||
68 | |||
69 | unsigned int prescale; | ||
70 | |||
71 | int irq; | ||
72 | }; | ||
73 | |||
74 | static struct adc_device *adc_dev; | ||
75 | |||
76 | static LIST_HEAD(adc_pending); | ||
77 | |||
78 | #define adc_dbg(_adc, msg...) dev_dbg(&(_adc)->pdev->dev, msg) | ||
79 | |||
80 | static inline void s3c_adc_convert(struct adc_device *adc) | ||
81 | { | ||
82 | unsigned con = readl(adc->regs + S3C2410_ADCCON); | ||
83 | |||
84 | con |= S3C2410_ADCCON_ENABLE_START; | ||
85 | writel(con, adc->regs + S3C2410_ADCCON); | ||
86 | } | ||
87 | |||
88 | static inline void s3c_adc_select(struct adc_device *adc, | ||
89 | struct s3c_adc_client *client) | ||
90 | { | ||
91 | unsigned con = readl(adc->regs + S3C2410_ADCCON); | ||
92 | |||
93 | client->select_cb(client, 1); | ||
94 | |||
95 | con &= ~S3C2410_ADCCON_MUXMASK; | ||
96 | con &= ~S3C2410_ADCCON_STDBM; | ||
97 | con &= ~S3C2410_ADCCON_STARTMASK; | ||
98 | |||
99 | if (!client->is_ts) | ||
100 | con |= S3C2410_ADCCON_SELMUX(client->channel); | ||
101 | |||
102 | writel(con, adc->regs + S3C2410_ADCCON); | ||
103 | } | ||
104 | |||
105 | static void s3c_adc_dbgshow(struct adc_device *adc) | ||
106 | { | ||
107 | adc_dbg(adc, "CON=%08x, TSC=%08x, DLY=%08x\n", | ||
108 | readl(adc->regs + S3C2410_ADCCON), | ||
109 | readl(adc->regs + S3C2410_ADCTSC), | ||
110 | readl(adc->regs + S3C2410_ADCDLY)); | ||
111 | } | ||
112 | |||
113 | static void s3c_adc_try(struct adc_device *adc) | ||
114 | { | ||
115 | struct s3c_adc_client *next = adc->ts_pend; | ||
116 | |||
117 | if (!next && !list_empty(&adc_pending)) { | ||
118 | next = list_first_entry(&adc_pending, | ||
119 | struct s3c_adc_client, pend); | ||
120 | list_del(&next->pend); | ||
121 | } else | ||
122 | adc->ts_pend = NULL; | ||
123 | |||
124 | if (next) { | ||
125 | adc_dbg(adc, "new client is %p\n", next); | ||
126 | adc->cur = next; | ||
127 | s3c_adc_select(adc, next); | ||
128 | s3c_adc_convert(adc); | ||
129 | s3c_adc_dbgshow(adc); | ||
130 | } | ||
131 | } | ||
132 | |||
133 | int s3c_adc_start(struct s3c_adc_client *client, | ||
134 | unsigned int channel, unsigned int nr_samples) | ||
135 | { | ||
136 | struct adc_device *adc = adc_dev; | ||
137 | unsigned long flags; | ||
138 | |||
139 | if (!adc) { | ||
140 | printk(KERN_ERR "%s: failed to find adc\n", __func__); | ||
141 | return -EINVAL; | ||
142 | } | ||
143 | |||
144 | if (client->is_ts && adc->ts_pend) | ||
145 | return -EAGAIN; | ||
146 | |||
147 | local_irq_save(flags); | ||
148 | |||
149 | client->channel = channel; | ||
150 | client->nr_samples = nr_samples; | ||
151 | |||
152 | if (client->is_ts) | ||
153 | adc->ts_pend = client; | ||
154 | else | ||
155 | list_add_tail(&client->pend, &adc_pending); | ||
156 | |||
157 | if (!adc->cur) | ||
158 | s3c_adc_try(adc); | ||
159 | local_irq_restore(flags); | ||
160 | |||
161 | return 0; | ||
162 | } | ||
163 | EXPORT_SYMBOL_GPL(s3c_adc_start); | ||
164 | |||
165 | static void s3c_convert_done(struct s3c_adc_client *client, | ||
166 | unsigned v, unsigned u, unsigned *left) | ||
167 | { | ||
168 | client->result = v; | ||
169 | wake_up(client->wait); | ||
170 | } | ||
171 | |||
172 | int s3c_adc_read(struct s3c_adc_client *client, unsigned int ch) | ||
173 | { | ||
174 | DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake); | ||
175 | int ret; | ||
176 | |||
177 | client->convert_cb = s3c_convert_done; | ||
178 | client->wait = &wake; | ||
179 | client->result = -1; | ||
180 | |||
181 | ret = s3c_adc_start(client, ch, 1); | ||
182 | if (ret < 0) | ||
183 | goto err; | ||
184 | |||
185 | ret = wait_event_timeout(wake, client->result >= 0, HZ / 2); | ||
186 | if (client->result < 0) { | ||
187 | ret = -ETIMEDOUT; | ||
188 | goto err; | ||
189 | } | ||
190 | |||
191 | client->convert_cb = NULL; | ||
192 | return client->result; | ||
193 | |||
194 | err: | ||
195 | return ret; | ||
196 | } | ||
197 | EXPORT_SYMBOL_GPL(s3c_adc_read); | ||
198 | |||
199 | static void s3c_adc_default_select(struct s3c_adc_client *client, | ||
200 | unsigned select) | ||
201 | { | ||
202 | } | ||
203 | |||
204 | struct s3c_adc_client *s3c_adc_register(struct platform_device *pdev, | ||
205 | void (*select)(struct s3c_adc_client *client, | ||
206 | unsigned int selected), | ||
207 | void (*conv)(struct s3c_adc_client *client, | ||
208 | unsigned d0, unsigned d1, | ||
209 | unsigned *samples_left), | ||
210 | unsigned int is_ts) | ||
211 | { | ||
212 | struct s3c_adc_client *client; | ||
213 | |||
214 | WARN_ON(!pdev); | ||
215 | |||
216 | if (!select) | ||
217 | select = s3c_adc_default_select; | ||
218 | |||
219 | if (!pdev) | ||
220 | return ERR_PTR(-EINVAL); | ||
221 | |||
222 | client = kzalloc(sizeof(struct s3c_adc_client), GFP_KERNEL); | ||
223 | if (!client) { | ||
224 | dev_err(&pdev->dev, "no memory for adc client\n"); | ||
225 | return ERR_PTR(-ENOMEM); | ||
226 | } | ||
227 | |||
228 | client->pdev = pdev; | ||
229 | client->is_ts = is_ts; | ||
230 | client->select_cb = select; | ||
231 | client->convert_cb = conv; | ||
232 | |||
233 | return client; | ||
234 | } | ||
235 | EXPORT_SYMBOL_GPL(s3c_adc_register); | ||
236 | |||
237 | void s3c_adc_release(struct s3c_adc_client *client) | ||
238 | { | ||
239 | /* We should really check that nothing is in progress. */ | ||
240 | if (adc_dev->cur == client) | ||
241 | adc_dev->cur = NULL; | ||
242 | if (adc_dev->ts_pend == client) | ||
243 | adc_dev->ts_pend = NULL; | ||
244 | else { | ||
245 | struct list_head *p, *n; | ||
246 | struct s3c_adc_client *tmp; | ||
247 | |||
248 | list_for_each_safe(p, n, &adc_pending) { | ||
249 | tmp = list_entry(p, struct s3c_adc_client, pend); | ||
250 | if (tmp == client) | ||
251 | list_del(&tmp->pend); | ||
252 | } | ||
253 | } | ||
254 | |||
255 | if (adc_dev->cur == NULL) | ||
256 | s3c_adc_try(adc_dev); | ||
257 | kfree(client); | ||
258 | } | ||
259 | EXPORT_SYMBOL_GPL(s3c_adc_release); | ||
260 | |||
261 | static irqreturn_t s3c_adc_irq(int irq, void *pw) | ||
262 | { | ||
263 | struct adc_device *adc = pw; | ||
264 | struct s3c_adc_client *client = adc->cur; | ||
265 | enum s3c_cpu_type cpu = platform_get_device_id(adc->pdev)->driver_data; | ||
266 | unsigned long flags; | ||
267 | unsigned data0, data1; | ||
268 | |||
269 | if (!client) { | ||
270 | dev_warn(&adc->pdev->dev, "%s: no adc pending\n", __func__); | ||
271 | goto exit; | ||
272 | } | ||
273 | |||
274 | data0 = readl(adc->regs + S3C2410_ADCDAT0); | ||
275 | data1 = readl(adc->regs + S3C2410_ADCDAT1); | ||
276 | adc_dbg(adc, "read %d: 0x%04x, 0x%04x\n", client->nr_samples, data0, data1); | ||
277 | |||
278 | client->nr_samples--; | ||
279 | |||
280 | if (cpu == TYPE_S3C64XX) { | ||
281 | /* S3C64XX ADC resolution is 12-bit */ | ||
282 | data0 &= 0xfff; | ||
283 | data1 &= 0xfff; | ||
284 | } else { | ||
285 | data0 &= 0x3ff; | ||
286 | data1 &= 0x3ff; | ||
287 | } | ||
288 | |||
289 | if (client->convert_cb) | ||
290 | (client->convert_cb)(client, data0, data1, &client->nr_samples); | ||
291 | |||
292 | if (client->nr_samples > 0) { | ||
293 | /* fire another conversion for this */ | ||
294 | |||
295 | client->select_cb(client, 1); | ||
296 | s3c_adc_convert(adc); | ||
297 | } else { | ||
298 | local_irq_save(flags); | ||
299 | (client->select_cb)(client, 0); | ||
300 | adc->cur = NULL; | ||
301 | |||
302 | s3c_adc_try(adc); | ||
303 | local_irq_restore(flags); | ||
304 | } | ||
305 | |||
306 | exit: | ||
307 | if (cpu == TYPE_S3C64XX) { | ||
308 | /* Clear ADC interrupt */ | ||
309 | writel(0, adc->regs + S3C64XX_ADCCLRINT); | ||
310 | } | ||
311 | return IRQ_HANDLED; | ||
312 | } | ||
313 | |||
314 | static int s3c_adc_probe(struct platform_device *pdev) | ||
315 | { | ||
316 | struct device *dev = &pdev->dev; | ||
317 | struct adc_device *adc; | ||
318 | struct resource *regs; | ||
319 | int ret; | ||
320 | unsigned tmp; | ||
321 | |||
322 | adc = kzalloc(sizeof(struct adc_device), GFP_KERNEL); | ||
323 | if (adc == NULL) { | ||
324 | dev_err(dev, "failed to allocate adc_device\n"); | ||
325 | return -ENOMEM; | ||
326 | } | ||
327 | |||
328 | adc->pdev = pdev; | ||
329 | adc->prescale = S3C2410_ADCCON_PRSCVL(49); | ||
330 | |||
331 | adc->irq = platform_get_irq(pdev, 1); | ||
332 | if (adc->irq <= 0) { | ||
333 | dev_err(dev, "failed to get adc irq\n"); | ||
334 | ret = -ENOENT; | ||
335 | goto err_alloc; | ||
336 | } | ||
337 | |||
338 | ret = request_irq(adc->irq, s3c_adc_irq, 0, dev_name(dev), adc); | ||
339 | if (ret < 0) { | ||
340 | dev_err(dev, "failed to attach adc irq\n"); | ||
341 | goto err_alloc; | ||
342 | } | ||
343 | |||
344 | adc->clk = clk_get(dev, "adc"); | ||
345 | if (IS_ERR(adc->clk)) { | ||
346 | dev_err(dev, "failed to get adc clock\n"); | ||
347 | ret = PTR_ERR(adc->clk); | ||
348 | goto err_irq; | ||
349 | } | ||
350 | |||
351 | regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); | ||
352 | if (!regs) { | ||
353 | dev_err(dev, "failed to find registers\n"); | ||
354 | ret = -ENXIO; | ||
355 | goto err_clk; | ||
356 | } | ||
357 | |||
358 | adc->regs = ioremap(regs->start, resource_size(regs)); | ||
359 | if (!adc->regs) { | ||
360 | dev_err(dev, "failed to map registers\n"); | ||
361 | ret = -ENXIO; | ||
362 | goto err_clk; | ||
363 | } | ||
364 | |||
365 | clk_enable(adc->clk); | ||
366 | |||
367 | tmp = adc->prescale | S3C2410_ADCCON_PRSCEN; | ||
368 | if (platform_get_device_id(pdev)->driver_data == TYPE_S3C64XX) { | ||
369 | /* Enable 12-bit ADC resolution */ | ||
370 | tmp |= S3C64XX_ADCCON_RESSEL; | ||
371 | } | ||
372 | writel(tmp, adc->regs + S3C2410_ADCCON); | ||
373 | |||
374 | dev_info(dev, "attached adc driver\n"); | ||
375 | |||
376 | platform_set_drvdata(pdev, adc); | ||
377 | adc_dev = adc; | ||
378 | |||
379 | return 0; | ||
380 | |||
381 | err_clk: | ||
382 | clk_put(adc->clk); | ||
383 | |||
384 | err_irq: | ||
385 | free_irq(adc->irq, adc); | ||
386 | |||
387 | err_alloc: | ||
388 | kfree(adc); | ||
389 | return ret; | ||
390 | } | ||
391 | |||
392 | static int __devexit s3c_adc_remove(struct platform_device *pdev) | ||
393 | { | ||
394 | struct adc_device *adc = platform_get_drvdata(pdev); | ||
395 | |||
396 | iounmap(adc->regs); | ||
397 | free_irq(adc->irq, adc); | ||
398 | clk_disable(adc->clk); | ||
399 | clk_put(adc->clk); | ||
400 | kfree(adc); | ||
401 | |||
402 | return 0; | ||
403 | } | ||
404 | |||
405 | #ifdef CONFIG_PM | ||
406 | static int s3c_adc_suspend(struct platform_device *pdev, pm_message_t state) | ||
407 | { | ||
408 | struct adc_device *adc = platform_get_drvdata(pdev); | ||
409 | u32 con; | ||
410 | |||
411 | con = readl(adc->regs + S3C2410_ADCCON); | ||
412 | con |= S3C2410_ADCCON_STDBM; | ||
413 | writel(con, adc->regs + S3C2410_ADCCON); | ||
414 | |||
415 | disable_irq(adc->irq); | ||
416 | clk_disable(adc->clk); | ||
417 | |||
418 | return 0; | ||
419 | } | ||
420 | |||
421 | static int s3c_adc_resume(struct platform_device *pdev) | ||
422 | { | ||
423 | struct adc_device *adc = platform_get_drvdata(pdev); | ||
424 | |||
425 | clk_enable(adc->clk); | ||
426 | enable_irq(adc->irq); | ||
427 | |||
428 | writel(adc->prescale | S3C2410_ADCCON_PRSCEN, | ||
429 | adc->regs + S3C2410_ADCCON); | ||
430 | |||
431 | return 0; | ||
432 | } | ||
433 | |||
434 | #else | ||
435 | #define s3c_adc_suspend NULL | ||
436 | #define s3c_adc_resume NULL | ||
437 | #endif | ||
438 | |||
439 | static struct platform_device_id s3c_adc_driver_ids[] = { | ||
440 | { | ||
441 | .name = "s3c24xx-adc", | ||
442 | .driver_data = TYPE_S3C24XX, | ||
443 | }, { | ||
444 | .name = "s3c64xx-adc", | ||
445 | .driver_data = TYPE_S3C64XX, | ||
446 | }, | ||
447 | { } | ||
448 | }; | ||
449 | MODULE_DEVICE_TABLE(platform, s3c_adc_driver_ids); | ||
450 | |||
451 | static struct platform_driver s3c_adc_driver = { | ||
452 | .id_table = s3c_adc_driver_ids, | ||
453 | .driver = { | ||
454 | .name = "s3c-adc", | ||
455 | .owner = THIS_MODULE, | ||
456 | }, | ||
457 | .probe = s3c_adc_probe, | ||
458 | .remove = __devexit_p(s3c_adc_remove), | ||
459 | .suspend = s3c_adc_suspend, | ||
460 | .resume = s3c_adc_resume, | ||
461 | }; | ||
462 | |||
463 | static int __init adc_init(void) | ||
464 | { | ||
465 | int ret; | ||
466 | |||
467 | ret = platform_driver_register(&s3c_adc_driver); | ||
468 | if (ret) | ||
469 | printk(KERN_ERR "%s: failed to add adc driver\n", __func__); | ||
470 | |||
471 | return ret; | ||
472 | } | ||
473 | |||
474 | arch_initcall(adc_init); | ||