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14#include <linux/module.h>
15#include <linux/kernel.h>
16#include <linux/platform_device.h>
17#include <linux/list.h>
18#include <linux/err.h>
19#include <linux/clk.h>
20#include <linux/interrupt.h>
21#include <linux/io.h>
22
23#include <plat/regs-adc.h>
24#include <plat/adc.h>
25
26
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32
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37
38
39struct s3c_adc_client {
40 struct platform_device *pdev;
41 struct list_head pend;
42
43 unsigned int nr_samples;
44 unsigned char is_ts;
45 unsigned char channel;
46
47 void (*select_cb)(unsigned selected);
48 void (*convert_cb)(unsigned val1, unsigned val2);
49};
50
51struct adc_device {
52 struct platform_device *pdev;
53 struct platform_device *owner;
54 struct clk *clk;
55 struct s3c_adc_client *cur;
56 struct s3c_adc_client *ts_pend;
57 void __iomem *regs;
58
59 unsigned int prescale;
60
61 int irq;
62};
63
64static struct adc_device *adc_dev;
65
66static LIST_HEAD(adc_pending);
67
68#define adc_dbg(_adc, msg...) dev_dbg(&(_adc)->pdev->dev, msg)
69
70static inline void s3c_adc_convert(struct adc_device *adc)
71{
72 unsigned con = readl(adc->regs + S3C2410_ADCCON);
73
74 con |= S3C2410_ADCCON_ENABLE_START;
75 writel(con, adc->regs + S3C2410_ADCCON);
76}
77
78static inline void s3c_adc_select(struct adc_device *adc,
79 struct s3c_adc_client *client)
80{
81 unsigned con = readl(adc->regs + S3C2410_ADCCON);
82
83 client->select_cb(1);
84
85 con &= ~S3C2410_ADCCON_MUXMASK;
86 con &= ~S3C2410_ADCCON_STDBM;
87 con &= ~S3C2410_ADCCON_STARTMASK;
88
89 if (!client->is_ts)
90 con |= S3C2410_ADCCON_SELMUX(client->channel);
91
92 writel(con, adc->regs + S3C2410_ADCCON);
93}
94
95static void s3c_adc_dbgshow(struct adc_device *adc)
96{
97 adc_dbg(adc, "CON=%08x, TSC=%08x, DLY=%08x\n",
98 readl(adc->regs + S3C2410_ADCCON),
99 readl(adc->regs + S3C2410_ADCTSC),
100 readl(adc->regs + S3C2410_ADCDLY));
101}
102
103static void s3c_adc_try(struct adc_device *adc)
104{
105 struct s3c_adc_client *next = adc->ts_pend;
106
107 if (!next && !list_empty(&adc_pending)) {
108 next = list_first_entry(&adc_pending,
109 struct s3c_adc_client, pend);
110 list_del(&next->pend);
111 } else
112 adc->ts_pend = NULL;
113
114 if (next) {
115 adc_dbg(adc, "new client is %p\n", next);
116 adc->cur = next;
117 s3c_adc_select(adc, next);
118 s3c_adc_convert(adc);
119 s3c_adc_dbgshow(adc);
120 }
121}
122
123int s3c_adc_start(struct s3c_adc_client *client,
124 unsigned int channel, unsigned int nr_samples)
125{
126 struct adc_device *adc = adc_dev;
127 unsigned long flags;
128
129 if (!adc) {
130 printk(KERN_ERR "%s: failed to find adc\n", __func__);
131 return -EINVAL;
132 }
133
134 if (client->is_ts && adc->ts_pend)
135 return -EAGAIN;
136
137 local_irq_save(flags);
138
139 client->channel = channel;
140 client->nr_samples = nr_samples;
141
142 if (client->is_ts)
143 adc->ts_pend = client;
144 else
145 list_add_tail(&client->pend, &adc_pending);
146
147 if (!adc->cur)
148 s3c_adc_try(adc);
149 local_irq_restore(flags);
150
151 return 0;
152}
153EXPORT_SYMBOL_GPL(s3c_adc_start);
154
155static void s3c_adc_default_select(unsigned select)
156{
157}
158
159struct s3c_adc_client *s3c_adc_register(struct platform_device *pdev,
160 void (*select)(unsigned int selected),
161 void (*conv)(unsigned d0, unsigned d1),
162 unsigned int is_ts)
163{
164 struct s3c_adc_client *client;
165
166 WARN_ON(!pdev);
167 WARN_ON(!conv);
168
169 if (!select)
170 select = s3c_adc_default_select;
171
172 if (!conv || !pdev)
173 return ERR_PTR(-EINVAL);
174
175 client = kzalloc(sizeof(struct s3c_adc_client), GFP_KERNEL);
176 if (!client) {
177 dev_err(&pdev->dev, "no memory for adc client\n");
178 return ERR_PTR(-ENOMEM);
179 }
180
181 client->pdev = pdev;
182 client->is_ts = is_ts;
183 client->select_cb = select;
184 client->convert_cb = conv;
185
186 return client;
187}
188EXPORT_SYMBOL_GPL(s3c_adc_register);
189
190void s3c_adc_release(struct s3c_adc_client *client)
191{
192
193 if (adc_dev->cur == client)
194 adc_dev->cur = NULL;
195 if (adc_dev->ts_pend == client)
196 adc_dev->ts_pend = NULL;
197 else {
198 struct list_head *p, *n;
199 struct s3c_adc_client *tmp;
200
201 list_for_each_safe(p, n, &adc_pending) {
202 tmp = list_entry(p, struct s3c_adc_client, pend);
203 if (tmp == client)
204 list_del(&tmp->pend);
205 }
206 }
207
208 if (adc_dev->cur == NULL)
209 s3c_adc_try(adc_dev);
210 kfree(client);
211}
212EXPORT_SYMBOL_GPL(s3c_adc_release);
213
214static irqreturn_t s3c_adc_irq(int irq, void *pw)
215{
216 struct adc_device *adc = pw;
217 struct s3c_adc_client *client = adc->cur;
218 unsigned long flags;
219 unsigned data0, data1;
220
221 if (!client) {
222 dev_warn(&adc->pdev->dev, "%s: no adc pending\n", __func__);
223 return IRQ_HANDLED;
224 }
225
226 data0 = readl(adc->regs + S3C2410_ADCDAT0);
227 data1 = readl(adc->regs + S3C2410_ADCDAT1);
228 adc_dbg(adc, "read %d: 0x%04x, 0x%04x\n", client->nr_samples, data0, data1);
229
230 (client->convert_cb)(data0 & 0x3ff, data1 & 0x3ff);
231
232 if (--client->nr_samples > 0) {
233
234
235 client->select_cb(1);
236 s3c_adc_convert(adc);
237 } else {
238 local_irq_save(flags);
239 (client->select_cb)(0);
240 adc->cur = NULL;
241
242 s3c_adc_try(adc);
243 local_irq_restore(flags);
244 }
245
246 return IRQ_HANDLED;
247}
248
249static int s3c_adc_probe(struct platform_device *pdev)
250{
251 struct device *dev = &pdev->dev;
252 struct adc_device *adc;
253 struct resource *regs;
254 int ret;
255
256 adc = kzalloc(sizeof(struct adc_device), GFP_KERNEL);
257 if (adc == NULL) {
258 dev_err(dev, "failed to allocate adc_device\n");
259 return -ENOMEM;
260 }
261
262 adc->pdev = pdev;
263 adc->prescale = S3C2410_ADCCON_PRSCVL(49);
264
265 adc->irq = platform_get_irq(pdev, 1);
266 if (adc->irq <= 0) {
267 dev_err(dev, "failed to get adc irq\n");
268 ret = -ENOENT;
269 goto err_alloc;
270 }
271
272 ret = request_irq(adc->irq, s3c_adc_irq, 0, dev_name(dev), adc);
273 if (ret < 0) {
274 dev_err(dev, "failed to attach adc irq\n");
275 goto err_alloc;
276 }
277
278 adc->clk = clk_get(dev, "adc");
279 if (IS_ERR(adc->clk)) {
280 dev_err(dev, "failed to get adc clock\n");
281 ret = PTR_ERR(adc->clk);
282 goto err_irq;
283 }
284
285 regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
286 if (!regs) {
287 dev_err(dev, "failed to find registers\n");
288 ret = -ENXIO;
289 goto err_clk;
290 }
291
292 adc->regs = ioremap(regs->start, resource_size(regs));
293 if (!adc->regs) {
294 dev_err(dev, "failed to map registers\n");
295 ret = -ENXIO;
296 goto err_clk;
297 }
298
299 clk_enable(adc->clk);
300
301 writel(adc->prescale | S3C2410_ADCCON_PRSCEN,
302 adc->regs + S3C2410_ADCCON);
303
304 dev_info(dev, "attached adc driver\n");
305
306 platform_set_drvdata(pdev, adc);
307 adc_dev = adc;
308
309 return 0;
310
311 err_clk:
312 clk_put(adc->clk);
313
314 err_irq:
315 free_irq(adc->irq, adc);
316
317 err_alloc:
318 kfree(adc);
319 return ret;
320}
321
322static int s3c_adc_remove(struct platform_device *pdev)
323{
324 struct adc_device *adc = platform_get_drvdata(pdev);
325
326 iounmap(adc->regs);
327 free_irq(adc->irq, adc);
328 clk_disable(adc->clk);
329 clk_put(adc->clk);
330 kfree(adc);
331
332 return 0;
333}
334
335#ifdef CONFIG_PM
336static int s3c_adc_suspend(struct platform_device *pdev, pm_message_t state)
337{
338 struct adc_device *adc = platform_get_drvdata(pdev);
339 u32 con;
340
341 con = readl(adc->regs + S3C2410_ADCCON);
342 con |= S3C2410_ADCCON_STDBM;
343 writel(con, adc->regs + S3C2410_ADCCON);
344
345 clk_disable(adc->clk);
346
347 return 0;
348}
349
350static int s3c_adc_resume(struct platform_device *pdev)
351{
352 struct adc_device *adc = platform_get_drvdata(pdev);
353
354 clk_enable(adc->clk);
355
356 writel(adc->prescale | S3C2410_ADCCON_PRSCEN,
357 adc->regs + S3C2410_ADCCON);
358
359 return 0;
360}
361
362#else
363#define s3c_adc_suspend NULL
364#define s3c_adc_resume NULL
365#endif
366
367static struct platform_driver s3c_adc_driver = {
368 .driver = {
369 .name = "s3c24xx-adc",
370 .owner = THIS_MODULE,
371 },
372 .probe = s3c_adc_probe,
373 .remove = __devexit_p(s3c_adc_remove),
374 .suspend = s3c_adc_suspend,
375 .resume = s3c_adc_resume,
376};
377
378static int __init adc_init(void)
379{
380 int ret;
381
382 ret = platform_driver_register(&s3c_adc_driver);
383 if (ret)
384 printk(KERN_ERR "%s: failed to add adc driver\n", __func__);
385
386 return ret;
387}
388
389arch_initcall(adc_init);
390
