xref: /openbmc/u-boot/drivers/adc/adc-uclass.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2015 Samsung Electronics
4  * Przemyslaw Marczak <p.marczak@samsung.com>
5  */
6 
7 #include <common.h>
8 #include <errno.h>
9 #include <div64.h>
10 #include <dm.h>
11 #include <dm/lists.h>
12 #include <dm/device-internal.h>
13 #include <dm/uclass-internal.h>
14 #include <adc.h>
15 #include <power/regulator.h>
16 
17 #define ADC_UCLASS_PLATDATA_SIZE	sizeof(struct adc_uclass_platdata)
18 #define CHECK_NUMBER			true
19 #define CHECK_MASK			(!CHECK_NUMBER)
20 
21 /* TODO: add support for timer uclass (for early calls) */
22 #ifdef CONFIG_SANDBOX_ARCH
23 #define sdelay(x)	udelay(x)
24 #else
25 extern void sdelay(unsigned long loops);
26 #endif
27 
28 static int check_channel(struct udevice *dev, int value, bool number_or_mask,
29 			 const char *caller_function)
30 {
31 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
32 	unsigned mask = number_or_mask ? (1 << value) : value;
33 
34 	/* For the real ADC hardware, some ADC channels can be inactive.
35 	 * For example if device has 4 analog channels, and only channels
36 	 * 1-st and 3-rd are valid, then channel mask is: 0b1010, so request
37 	 * with mask 0b1110 should return an error.
38 	*/
39 	if ((uc_pdata->channel_mask >= mask) && (uc_pdata->channel_mask & mask))
40 		return 0;
41 
42 	printf("Error in %s/%s().\nWrong channel selection for device: %s\n",
43 	       __FILE__, caller_function, dev->name);
44 
45 	return -EINVAL;
46 }
47 
48 static int adc_supply_enable(struct udevice *dev)
49 {
50 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
51 	const char *supply_type;
52 	int ret = 0;
53 
54 	if (uc_pdata->vdd_supply) {
55 		supply_type = "vdd";
56 		ret = regulator_set_enable(uc_pdata->vdd_supply, true);
57 	}
58 
59 	if (!ret && uc_pdata->vss_supply) {
60 		supply_type = "vss";
61 		ret = regulator_set_enable(uc_pdata->vss_supply, true);
62 	}
63 
64 	if (ret)
65 		pr_err("%s: can't enable %s-supply!", dev->name, supply_type);
66 
67 	return ret;
68 }
69 
70 int adc_data_mask(struct udevice *dev, unsigned int *data_mask)
71 {
72 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
73 
74 	if (!uc_pdata)
75 		return -ENOSYS;
76 
77 	*data_mask = uc_pdata->data_mask;
78 	return 0;
79 }
80 
81 int adc_channel_mask(struct udevice *dev, unsigned int *channel_mask)
82 {
83 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
84 
85 	if (!uc_pdata)
86 		return -ENOSYS;
87 
88 	*channel_mask = uc_pdata->channel_mask;
89 
90 	return 0;
91 }
92 
93 int adc_stop(struct udevice *dev)
94 {
95 	const struct adc_ops *ops = dev_get_driver_ops(dev);
96 
97 	if (!ops->stop)
98 		return -ENOSYS;
99 
100 	return ops->stop(dev);
101 }
102 
103 int adc_start_channel(struct udevice *dev, int channel)
104 {
105 	const struct adc_ops *ops = dev_get_driver_ops(dev);
106 	int ret;
107 
108 	if (!ops->start_channel)
109 		return -ENOSYS;
110 
111 	ret = check_channel(dev, channel, CHECK_NUMBER, __func__);
112 	if (ret)
113 		return ret;
114 
115 	ret = adc_supply_enable(dev);
116 	if (ret)
117 		return ret;
118 
119 	return ops->start_channel(dev, channel);
120 }
121 
122 int adc_start_channels(struct udevice *dev, unsigned int channel_mask)
123 {
124 	const struct adc_ops *ops = dev_get_driver_ops(dev);
125 	int ret;
126 
127 	if (!ops->start_channels)
128 		return -ENOSYS;
129 
130 	ret = check_channel(dev, channel_mask, CHECK_MASK, __func__);
131 	if (ret)
132 		return ret;
133 
134 	ret = adc_supply_enable(dev);
135 	if (ret)
136 		return ret;
137 
138 	return ops->start_channels(dev, channel_mask);
139 }
140 
141 int adc_channel_data(struct udevice *dev, int channel, unsigned int *data)
142 {
143 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
144 	const struct adc_ops *ops = dev_get_driver_ops(dev);
145 	unsigned int timeout_us = uc_pdata->data_timeout_us;
146 	int ret;
147 
148 	if (!ops->channel_data)
149 		return -ENOSYS;
150 
151 	ret = check_channel(dev, channel, CHECK_NUMBER, __func__);
152 	if (ret)
153 		return ret;
154 
155 	do {
156 		ret = ops->channel_data(dev, channel, data);
157 		if (!ret || ret != -EBUSY)
158 			break;
159 
160 		/* TODO: use timer uclass (for early calls). */
161 		sdelay(5);
162 	} while (timeout_us--);
163 
164 	return ret;
165 }
166 
167 int adc_channels_data(struct udevice *dev, unsigned int channel_mask,
168 		      struct adc_channel *channels)
169 {
170 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
171 	unsigned int timeout_us = uc_pdata->multidata_timeout_us;
172 	const struct adc_ops *ops = dev_get_driver_ops(dev);
173 	int ret;
174 
175 	if (!ops->channels_data)
176 		return -ENOSYS;
177 
178 	ret = check_channel(dev, channel_mask, CHECK_MASK, __func__);
179 	if (ret)
180 		return ret;
181 
182 	do {
183 		ret = ops->channels_data(dev, channel_mask, channels);
184 		if (!ret || ret != -EBUSY)
185 			break;
186 
187 		/* TODO: use timer uclass (for early calls). */
188 		sdelay(5);
189 	} while (timeout_us--);
190 
191 	return ret;
192 }
193 
194 int adc_channel_single_shot(const char *name, int channel, unsigned int *data)
195 {
196 	struct udevice *dev;
197 	int ret;
198 
199 	ret = uclass_get_device_by_name(UCLASS_ADC, name, &dev);
200 	if (ret)
201 		return ret;
202 
203 	ret = adc_start_channel(dev, channel);
204 	if (ret)
205 		return ret;
206 
207 	ret = adc_channel_data(dev, channel, data);
208 	if (ret)
209 		return ret;
210 
211 	return 0;
212 }
213 
214 static int _adc_channels_single_shot(struct udevice *dev,
215 				     unsigned int channel_mask,
216 				     struct adc_channel *channels)
217 {
218 	unsigned int data;
219 	int channel, ret;
220 
221 	for (channel = 0; channel <= ADC_MAX_CHANNEL; channel++) {
222 		/* Check channel bit. */
223 		if (!((channel_mask >> channel) & 0x1))
224 			continue;
225 
226 		ret = adc_start_channel(dev, channel);
227 		if (ret)
228 			return ret;
229 
230 		ret = adc_channel_data(dev, channel, &data);
231 		if (ret)
232 			return ret;
233 
234 		channels->id = channel;
235 		channels->data = data;
236 		channels++;
237 	}
238 
239 	return 0;
240 }
241 
242 int adc_channels_single_shot(const char *name, unsigned int channel_mask,
243 			     struct adc_channel *channels)
244 {
245 	struct udevice *dev;
246 	int ret;
247 
248 	ret = uclass_get_device_by_name(UCLASS_ADC, name, &dev);
249 	if (ret)
250 		return ret;
251 
252 	ret = adc_start_channels(dev, channel_mask);
253 	if (ret)
254 		goto try_manual;
255 
256 	ret = adc_channels_data(dev, channel_mask, channels);
257 	if (ret)
258 		return ret;
259 
260 	return 0;
261 
262 try_manual:
263 	if (ret != -ENOSYS)
264 		return ret;
265 
266 	return _adc_channels_single_shot(dev, channel_mask, channels);
267 }
268 
269 static int adc_vdd_platdata_update(struct udevice *dev)
270 {
271 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
272 	int ret;
273 
274 	/* Warning!
275 	 * This function can't return supply device before its bind.
276 	 * Please pay attention to proper fdt scan sequence. If ADC device
277 	 * will bind before its supply regulator device, then the below 'get'
278 	 * will return an error.
279 	 */
280 	if (!uc_pdata->vdd_supply)
281 		return 0;
282 
283 	ret = regulator_get_value(uc_pdata->vdd_supply);
284 	if (ret < 0)
285 		return ret;
286 
287 	uc_pdata->vdd_microvolts = ret;
288 
289 	return 0;
290 }
291 
292 static int adc_vss_platdata_update(struct udevice *dev)
293 {
294 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
295 	int ret;
296 
297 	if (!uc_pdata->vss_supply)
298 		return 0;
299 
300 	ret = regulator_get_value(uc_pdata->vss_supply);
301 	if (ret < 0)
302 		return ret;
303 
304 	uc_pdata->vss_microvolts = ret;
305 
306 	return 0;
307 }
308 
309 int adc_vdd_value(struct udevice *dev, int *uV)
310 {
311 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
312 	int ret, value_sign = uc_pdata->vdd_polarity_negative ? -1 : 1;
313 
314 	/* Update the regulator Value. */
315 	ret = adc_vdd_platdata_update(dev);
316 	if (ret)
317 		return ret;
318 
319 	if (uc_pdata->vdd_microvolts == -ENODATA)
320 		return -ENODATA;
321 
322 	*uV = uc_pdata->vdd_microvolts * value_sign;
323 
324 	return 0;
325 }
326 
327 int adc_vss_value(struct udevice *dev, int *uV)
328 {
329 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
330 	int ret, value_sign = uc_pdata->vss_polarity_negative ? -1 : 1;
331 
332 	/* Update the regulator Value. */
333 	ret = adc_vss_platdata_update(dev);
334 	if (ret)
335 		return ret;
336 
337 	if (uc_pdata->vss_microvolts == -ENODATA)
338 		return -ENODATA;
339 
340 	*uV = uc_pdata->vss_microvolts * value_sign;
341 
342 	return 0;
343 }
344 
345 int adc_raw_to_uV(struct udevice *dev, unsigned int raw, int *uV)
346 {
347 	unsigned int data_mask;
348 	int ret, val, vref;
349 	u64 raw64 = raw;
350 
351 	ret = adc_vdd_value(dev, &vref);
352 	if (ret)
353 		return ret;
354 
355 	if (!adc_vss_value(dev, &val))
356 		vref -= val;
357 
358 	ret = adc_data_mask(dev, &data_mask);
359 	if (ret)
360 		return ret;
361 
362 	raw64 *= vref;
363 	do_div(raw64, data_mask);
364 	*uV = raw64;
365 
366 	return 0;
367 }
368 
369 static int adc_vdd_platdata_set(struct udevice *dev)
370 {
371 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
372 	int ret;
373 	char *prop;
374 
375 	prop = "vdd-polarity-negative";
376 	uc_pdata->vdd_polarity_negative = dev_read_bool(dev, prop);
377 
378 	/* Optionally get regulators */
379 	ret = device_get_supply_regulator(dev, "vdd-supply",
380 					  &uc_pdata->vdd_supply);
381 	if (!ret)
382 		return adc_vdd_platdata_update(dev);
383 
384 	if (ret != -ENOENT)
385 		return ret;
386 
387 	/* No vdd-supply phandle. */
388 	prop  = "vdd-microvolts";
389 	uc_pdata->vdd_microvolts = dev_read_u32_default(dev, prop, -ENODATA);
390 
391 	return 0;
392 }
393 
394 static int adc_vss_platdata_set(struct udevice *dev)
395 {
396 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
397 	int ret;
398 	char *prop;
399 
400 	prop = "vss-polarity-negative";
401 	uc_pdata->vss_polarity_negative = dev_read_bool(dev, prop);
402 
403 	ret = device_get_supply_regulator(dev, "vss-supply",
404 					  &uc_pdata->vss_supply);
405 	if (!ret)
406 		return adc_vss_platdata_update(dev);
407 
408 	if (ret != -ENOENT)
409 		return ret;
410 
411 	/* No vss-supply phandle. */
412 	prop = "vss-microvolts";
413 	uc_pdata->vss_microvolts = dev_read_u32_default(dev, prop, -ENODATA);
414 
415 	return 0;
416 }
417 
418 static int adc_pre_probe(struct udevice *dev)
419 {
420 	int ret;
421 
422 	/* Set ADC VDD platdata: polarity, uV, regulator (phandle). */
423 	ret = adc_vdd_platdata_set(dev);
424 	if (ret)
425 		pr_err("%s: Can't update Vdd. Error: %d", dev->name, ret);
426 
427 	/* Set ADC VSS platdata: polarity, uV, regulator (phandle). */
428 	ret = adc_vss_platdata_set(dev);
429 	if (ret)
430 		pr_err("%s: Can't update Vss. Error: %d", dev->name, ret);
431 
432 	return 0;
433 }
434 
435 UCLASS_DRIVER(adc) = {
436 	.id	= UCLASS_ADC,
437 	.name	= "adc",
438 	.pre_probe =  adc_pre_probe,
439 	.per_device_platdata_auto_alloc_size = ADC_UCLASS_PLATDATA_SIZE,
440 };
441