xref: /openbmc/u-boot/drivers/adc/adc-uclass.c (revision 85fc970d)
1 /*
2  * Copyright (C) 2015 Samsung Electronics
3  * Przemyslaw Marczak <p.marczak@samsung.com>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <errno.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 DECLARE_GLOBAL_DATA_PTR;
18 
19 #define ADC_UCLASS_PLATDATA_SIZE	sizeof(struct adc_uclass_platdata)
20 #define CHECK_NUMBER			true
21 #define CHECK_MASK			(!CHECK_NUMBER)
22 
23 /* TODO: add support for timer uclass (for early calls) */
24 #ifdef CONFIG_SANDBOX_ARCH
25 #define sdelay(x)	udelay(x)
26 #else
27 extern void sdelay(unsigned long loops);
28 #endif
29 
30 static int check_channel(struct udevice *dev, int value, bool number_or_mask,
31 			 const char *caller_function)
32 {
33 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
34 	unsigned mask = number_or_mask ? (1 << value) : value;
35 
36 	/* For the real ADC hardware, some ADC channels can be inactive.
37 	 * For example if device has 4 analog channels, and only channels
38 	 * 1-st and 3-rd are valid, then channel mask is: 0b1010, so request
39 	 * with mask 0b1110 should return an error.
40 	*/
41 	if ((uc_pdata->channel_mask >= mask) && (uc_pdata->channel_mask & mask))
42 		return 0;
43 
44 	printf("Error in %s/%s().\nWrong channel selection for device: %s\n",
45 	       __FILE__, caller_function, dev->name);
46 
47 	return -EINVAL;
48 }
49 
50 static int adc_supply_enable(struct udevice *dev)
51 {
52 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
53 	const char *supply_type;
54 	int ret = 0;
55 
56 	if (uc_pdata->vdd_supply) {
57 		supply_type = "vdd";
58 		ret = regulator_set_enable(uc_pdata->vdd_supply, true);
59 	}
60 
61 	if (!ret && uc_pdata->vss_supply) {
62 		supply_type = "vss";
63 		ret = regulator_set_enable(uc_pdata->vss_supply, true);
64 	}
65 
66 	if (ret)
67 		error("%s: can't enable %s-supply!", dev->name, supply_type);
68 
69 	return ret;
70 }
71 
72 int adc_data_mask(struct udevice *dev, unsigned int *data_mask)
73 {
74 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
75 
76 	if (!uc_pdata)
77 		return -ENOSYS;
78 
79 	*data_mask = uc_pdata->data_mask;
80 	return 0;
81 }
82 
83 int adc_stop(struct udevice *dev)
84 {
85 	const struct adc_ops *ops = dev_get_driver_ops(dev);
86 
87 	if (!ops->stop)
88 		return -ENOSYS;
89 
90 	return ops->stop(dev);
91 }
92 
93 int adc_start_channel(struct udevice *dev, int channel)
94 {
95 	const struct adc_ops *ops = dev_get_driver_ops(dev);
96 	int ret;
97 
98 	if (!ops->start_channel)
99 		return -ENOSYS;
100 
101 	ret = check_channel(dev, channel, CHECK_NUMBER, __func__);
102 	if (ret)
103 		return ret;
104 
105 	ret = adc_supply_enable(dev);
106 	if (ret)
107 		return ret;
108 
109 	return ops->start_channel(dev, channel);
110 }
111 
112 int adc_start_channels(struct udevice *dev, unsigned int channel_mask)
113 {
114 	const struct adc_ops *ops = dev_get_driver_ops(dev);
115 	int ret;
116 
117 	if (!ops->start_channels)
118 		return -ENOSYS;
119 
120 	ret = check_channel(dev, channel_mask, CHECK_MASK, __func__);
121 	if (ret)
122 		return ret;
123 
124 	ret = adc_supply_enable(dev);
125 	if (ret)
126 		return ret;
127 
128 	return ops->start_channels(dev, channel_mask);
129 }
130 
131 int adc_channel_data(struct udevice *dev, int channel, unsigned int *data)
132 {
133 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
134 	const struct adc_ops *ops = dev_get_driver_ops(dev);
135 	unsigned int timeout_us = uc_pdata->data_timeout_us;
136 	int ret;
137 
138 	if (!ops->channel_data)
139 		return -ENOSYS;
140 
141 	ret = check_channel(dev, channel, CHECK_NUMBER, __func__);
142 	if (ret)
143 		return ret;
144 
145 	do {
146 		ret = ops->channel_data(dev, channel, data);
147 		if (!ret || ret != -EBUSY)
148 			break;
149 
150 		/* TODO: use timer uclass (for early calls). */
151 		sdelay(5);
152 	} while (timeout_us--);
153 
154 	return ret;
155 }
156 
157 int adc_channels_data(struct udevice *dev, unsigned int channel_mask,
158 		      struct adc_channel *channels)
159 {
160 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
161 	unsigned int timeout_us = uc_pdata->multidata_timeout_us;
162 	const struct adc_ops *ops = dev_get_driver_ops(dev);
163 	int ret;
164 
165 	if (!ops->channels_data)
166 		return -ENOSYS;
167 
168 	ret = check_channel(dev, channel_mask, CHECK_MASK, __func__);
169 	if (ret)
170 		return ret;
171 
172 	do {
173 		ret = ops->channels_data(dev, channel_mask, channels);
174 		if (!ret || ret != -EBUSY)
175 			break;
176 
177 		/* TODO: use timer uclass (for early calls). */
178 		sdelay(5);
179 	} while (timeout_us--);
180 
181 	return ret;
182 }
183 
184 int adc_channel_single_shot(const char *name, int channel, unsigned int *data)
185 {
186 	struct udevice *dev;
187 	int ret;
188 
189 	ret = uclass_get_device_by_name(UCLASS_ADC, name, &dev);
190 	if (ret)
191 		return ret;
192 
193 	ret = adc_start_channel(dev, channel);
194 	if (ret)
195 		return ret;
196 
197 	ret = adc_channel_data(dev, channel, data);
198 	if (ret)
199 		return ret;
200 
201 	return 0;
202 }
203 
204 static int _adc_channels_single_shot(struct udevice *dev,
205 				     unsigned int channel_mask,
206 				     struct adc_channel *channels)
207 {
208 	unsigned int data;
209 	int channel, ret;
210 
211 	for (channel = 0; channel <= ADC_MAX_CHANNEL; channel++) {
212 		/* Check channel bit. */
213 		if (!((channel_mask >> channel) & 0x1))
214 			continue;
215 
216 		ret = adc_start_channel(dev, channel);
217 		if (ret)
218 			return ret;
219 
220 		ret = adc_channel_data(dev, channel, &data);
221 		if (ret)
222 			return ret;
223 
224 		channels->id = channel;
225 		channels->data = data;
226 		channels++;
227 	}
228 
229 	return 0;
230 }
231 
232 int adc_channels_single_shot(const char *name, unsigned int channel_mask,
233 			     struct adc_channel *channels)
234 {
235 	struct udevice *dev;
236 	int ret;
237 
238 	ret = uclass_get_device_by_name(UCLASS_ADC, name, &dev);
239 	if (ret)
240 		return ret;
241 
242 	ret = adc_start_channels(dev, channel_mask);
243 	if (ret)
244 		goto try_manual;
245 
246 	ret = adc_channels_data(dev, channel_mask, channels);
247 	if (ret)
248 		return ret;
249 
250 	return 0;
251 
252 try_manual:
253 	if (ret != -ENOSYS)
254 		return ret;
255 
256 	return _adc_channels_single_shot(dev, channel_mask, channels);
257 }
258 
259 static int adc_vdd_platdata_update(struct udevice *dev)
260 {
261 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
262 	int ret;
263 
264 	/* Warning!
265 	 * This function can't return supply device before its bind.
266 	 * Please pay attention to proper fdt scan sequence. If ADC device
267 	 * will bind before its supply regulator device, then the below 'get'
268 	 * will return an error.
269 	 */
270 	ret = device_get_supply_regulator(dev, "vdd-supply",
271 					  &uc_pdata->vdd_supply);
272 	if (ret)
273 		return ret;
274 
275 	ret = regulator_get_value(uc_pdata->vdd_supply);
276 	if (ret < 0)
277 		return ret;
278 
279 	uc_pdata->vdd_microvolts = ret;
280 
281 	return 0;
282 }
283 
284 static int adc_vss_platdata_update(struct udevice *dev)
285 {
286 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
287 	int ret;
288 
289 	ret = device_get_supply_regulator(dev, "vss-supply",
290 					  &uc_pdata->vss_supply);
291 	if (ret)
292 		return ret;
293 
294 	ret = regulator_get_value(uc_pdata->vss_supply);
295 	if (ret < 0)
296 		return ret;
297 
298 	uc_pdata->vss_microvolts = ret;
299 
300 	return 0;
301 }
302 
303 int adc_vdd_value(struct udevice *dev, int *uV)
304 {
305 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
306 	int ret, value_sign = uc_pdata->vdd_polarity_negative ? -1 : 1;
307 
308 	if (!uc_pdata->vdd_supply)
309 		goto nodev;
310 
311 	/* Update the regulator Value. */
312 	ret = adc_vdd_platdata_update(dev);
313 	if (ret)
314 		return ret;
315 nodev:
316 	if (uc_pdata->vdd_microvolts == -ENODATA)
317 		return -ENODATA;
318 
319 	*uV = uc_pdata->vdd_microvolts * value_sign;
320 
321 	return 0;
322 }
323 
324 int adc_vss_value(struct udevice *dev, int *uV)
325 {
326 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
327 	int ret, value_sign = uc_pdata->vss_polarity_negative ? -1 : 1;
328 
329 	if (!uc_pdata->vss_supply)
330 		goto nodev;
331 
332 	/* Update the regulator Value. */
333 	ret = adc_vss_platdata_update(dev);
334 	if (ret)
335 		return ret;
336 nodev:
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 static int adc_vdd_platdata_set(struct udevice *dev)
346 {
347 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
348 	int ret;
349 	char *prop;
350 
351 	prop = "vdd-polarity-negative";
352 	uc_pdata->vdd_polarity_negative = dev_read_bool(dev, prop);
353 
354 	ret = adc_vdd_platdata_update(dev);
355 	if (ret != -ENOENT)
356 		return ret;
357 
358 	/* No vdd-supply phandle. */
359 	prop  = "vdd-microvolts";
360 	uc_pdata->vdd_microvolts = dev_read_u32_default(dev, prop, -ENODATA);
361 
362 	return 0;
363 }
364 
365 static int adc_vss_platdata_set(struct udevice *dev)
366 {
367 	struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
368 	int ret;
369 	char *prop;
370 
371 	prop = "vss-polarity-negative";
372 	uc_pdata->vss_polarity_negative = dev_read_bool(dev, prop);
373 
374 	ret = adc_vss_platdata_update(dev);
375 	if (ret != -ENOENT)
376 		return ret;
377 
378 	/* No vss-supply phandle. */
379 	prop = "vss-microvolts";
380 	uc_pdata->vss_microvolts = dev_read_u32_default(dev, prop, -ENODATA);
381 
382 	return 0;
383 }
384 
385 static int adc_pre_probe(struct udevice *dev)
386 {
387 	int ret;
388 
389 	/* Set ADC VDD platdata: polarity, uV, regulator (phandle). */
390 	ret = adc_vdd_platdata_set(dev);
391 	if (ret)
392 		error("%s: Can't update Vdd. Error: %d", dev->name, ret);
393 
394 	/* Set ADC VSS platdata: polarity, uV, regulator (phandle). */
395 	ret = adc_vss_platdata_set(dev);
396 	if (ret)
397 		error("%s: Can't update Vss. Error: %d", dev->name, ret);
398 
399 	return 0;
400 }
401 
402 UCLASS_DRIVER(adc) = {
403 	.id	= UCLASS_ADC,
404 	.name	= "adc",
405 	.pre_probe =  adc_pre_probe,
406 	.per_device_platdata_auto_alloc_size = ADC_UCLASS_PLATDATA_SIZE,
407 };
408