xref: /linux/drivers/hwmon/mc13783-adc.c (revision ebc733e54a1a79ea2dde2ba5121ae73a188e20d4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Driver for the ADC on Freescale Semiconductor MC13783 and MC13892 PMICs.
4  *
5  * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
6  * Copyright (C) 2009 Sascha Hauer, Pengutronix
7  */
8 
9 #include <linux/mfd/mc13xxx.h>
10 #include <linux/platform_device.h>
11 #include <linux/hwmon-sysfs.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/mod_devicetable.h>
15 #include <linux/hwmon.h>
16 #include <linux/slab.h>
17 #include <linux/init.h>
18 #include <linux/err.h>
19 
20 #define DRIVER_NAME	"mc13783-adc"
21 
22 /* platform device id driver data */
23 #define MC13783_ADC_16CHANS	1
24 #define MC13783_ADC_BPDIV2	2
25 
26 struct mc13783_adc_priv {
27 	struct mc13xxx *mc13xxx;
28 	struct device *hwmon_dev;
29 	char name[PLATFORM_NAME_SIZE];
30 };
31 
32 static ssize_t name_show(struct device *dev, struct device_attribute *devattr,
33 			 char *buf)
34 {
35 	struct mc13783_adc_priv *priv = dev_get_drvdata(dev);
36 
37 	return sprintf(buf, "%s\n", priv->name);
38 }
39 
40 static int mc13783_adc_read(struct device *dev,
41 		struct device_attribute *devattr, unsigned int *val)
42 {
43 	struct mc13783_adc_priv *priv = dev_get_drvdata(dev);
44 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
45 	unsigned int channel = attr->index;
46 	unsigned int sample[4];
47 	int ret;
48 
49 	ret = mc13xxx_adc_do_conversion(priv->mc13xxx,
50 			MC13XXX_ADC_MODE_MULT_CHAN,
51 			channel, 0, 0, sample);
52 	if (ret)
53 		return ret;
54 
55 	/* ADIN7 subchannels */
56 	if (channel >= 16)
57 		channel = 7;
58 
59 	channel &= 0x7;
60 
61 	*val = (sample[channel % 4] >> (channel > 3 ? 14 : 2)) & 0x3ff;
62 
63 	return 0;
64 }
65 
66 static ssize_t mc13783_adc_bp_show(struct device *dev,
67 				   struct device_attribute *devattr,
68 				   char *buf)
69 {
70 	unsigned val;
71 	struct platform_device *pdev = to_platform_device(dev);
72 	kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
73 	int ret = mc13783_adc_read(dev, devattr, &val);
74 
75 	if (ret)
76 		return ret;
77 
78 	if (driver_data & MC13783_ADC_BPDIV2)
79 		val = DIV_ROUND_CLOSEST(val * 9, 2);
80 	else
81 		/*
82 		 * BP (channel 2) reports with offset 2.4V to the actual value
83 		 * to fit the input range of the ADC.  unit = 2.25mV = 9/4 mV.
84 		 */
85 		val = DIV_ROUND_CLOSEST(val * 9, 4) + 2400;
86 
87 	return sprintf(buf, "%u\n", val);
88 }
89 
90 static ssize_t mc13783_adc_gp_show(struct device *dev,
91 				   struct device_attribute *devattr,
92 				   char *buf)
93 {
94 	unsigned val;
95 	int ret = mc13783_adc_read(dev, devattr, &val);
96 
97 	if (ret)
98 		return ret;
99 
100 	/*
101 	 * input range is [0, 2.3V], val has 10 bits, so each bit
102 	 * is worth 9/4 mV.
103 	 */
104 	val = DIV_ROUND_CLOSEST(val * 9, 4);
105 
106 	return sprintf(buf, "%u\n", val);
107 }
108 
109 static ssize_t mc13783_adc_uid_show(struct device *dev,
110 				    struct device_attribute *devattr,
111 				    char *buf)
112 {
113 	unsigned int val;
114 	struct platform_device *pdev = to_platform_device(dev);
115 	kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
116 	int ret = mc13783_adc_read(dev, devattr, &val);
117 
118 	if (ret)
119 		return ret;
120 
121 	if (driver_data & MC13783_ADC_BPDIV2)
122 		/* MC13892 have 1/2 divider, input range is [0, 4.800V] */
123 		val = DIV_ROUND_CLOSEST(val * 4800, 1024);
124 	else
125 		/* MC13783 have 0.9 divider, input range is [0, 2.555V] */
126 		val = DIV_ROUND_CLOSEST(val * 2555, 1024);
127 
128 	return sprintf(buf, "%u\n", val);
129 }
130 
131 static ssize_t mc13783_adc_temp_show(struct device *dev,
132 				     struct device_attribute *devattr,
133 				     char *buf)
134 {
135 	unsigned int val;
136 	struct platform_device *pdev = to_platform_device(dev);
137 	kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
138 	int ret = mc13783_adc_read(dev, devattr, &val);
139 
140 	if (ret)
141 		return ret;
142 
143 	if (driver_data & MC13783_ADC_BPDIV2) {
144 		/*
145 		 * MC13892:
146 		 * Die Temperature Read Out Code at 25C 680
147 		 * Temperature change per LSB +0.4244C
148 		 */
149 		ret = DIV_ROUND_CLOSEST(-2635920 + val * 4244, 10);
150 	} else {
151 		/*
152 		 * MC13783:
153 		 * Die Temperature Read Out Code at 25C 282
154 		 * Temperature change per LSB -1.14C
155 		 */
156 		ret = 346480 - 1140 * val;
157 	}
158 
159 	return sprintf(buf, "%d\n", ret);
160 }
161 
162 static DEVICE_ATTR_RO(name);
163 static SENSOR_DEVICE_ATTR_RO(in2_input, mc13783_adc_bp, 2);
164 static SENSOR_DEVICE_ATTR_RO(in5_input, mc13783_adc_gp, 5);
165 static SENSOR_DEVICE_ATTR_RO(in6_input, mc13783_adc_gp, 6);
166 static SENSOR_DEVICE_ATTR_RO(in7_input, mc13783_adc_gp, 7);
167 static SENSOR_DEVICE_ATTR_RO(in8_input, mc13783_adc_gp, 8);
168 static SENSOR_DEVICE_ATTR_RO(in9_input, mc13783_adc_gp, 9);
169 static SENSOR_DEVICE_ATTR_RO(in10_input, mc13783_adc_gp, 10);
170 static SENSOR_DEVICE_ATTR_RO(in11_input, mc13783_adc_gp, 11);
171 static SENSOR_DEVICE_ATTR_RO(in12_input, mc13783_adc_gp, 12);
172 static SENSOR_DEVICE_ATTR_RO(in13_input, mc13783_adc_gp, 13);
173 static SENSOR_DEVICE_ATTR_RO(in14_input, mc13783_adc_gp, 14);
174 static SENSOR_DEVICE_ATTR_RO(in15_input, mc13783_adc_gp, 15);
175 static SENSOR_DEVICE_ATTR_RO(in16_input, mc13783_adc_uid, 16);
176 static SENSOR_DEVICE_ATTR_RO(temp1_input, mc13783_adc_temp, 17);
177 
178 static struct attribute *mc13783_attr_base[] = {
179 	&dev_attr_name.attr,
180 	&sensor_dev_attr_in2_input.dev_attr.attr,
181 	&sensor_dev_attr_in5_input.dev_attr.attr,
182 	&sensor_dev_attr_in6_input.dev_attr.attr,
183 	&sensor_dev_attr_in7_input.dev_attr.attr,
184 	&sensor_dev_attr_in16_input.dev_attr.attr,
185 	&sensor_dev_attr_temp1_input.dev_attr.attr,
186 	NULL
187 };
188 
189 static const struct attribute_group mc13783_group_base = {
190 	.attrs = mc13783_attr_base,
191 };
192 
193 /* these are only used if MC13783_ADC_16CHANS is provided in driver data */
194 static struct attribute *mc13783_attr_16chans[] = {
195 	&sensor_dev_attr_in8_input.dev_attr.attr,
196 	&sensor_dev_attr_in9_input.dev_attr.attr,
197 	&sensor_dev_attr_in10_input.dev_attr.attr,
198 	&sensor_dev_attr_in11_input.dev_attr.attr,
199 	NULL
200 };
201 
202 static const struct attribute_group mc13783_group_16chans = {
203 	.attrs = mc13783_attr_16chans,
204 };
205 
206 /* last four channels may be occupied by the touchscreen */
207 static struct attribute *mc13783_attr_ts[] = {
208 	&sensor_dev_attr_in12_input.dev_attr.attr,
209 	&sensor_dev_attr_in13_input.dev_attr.attr,
210 	&sensor_dev_attr_in14_input.dev_attr.attr,
211 	&sensor_dev_attr_in15_input.dev_attr.attr,
212 	NULL
213 };
214 
215 static const struct attribute_group mc13783_group_ts = {
216 	.attrs = mc13783_attr_ts,
217 };
218 
219 static int mc13783_adc_use_touchscreen(struct platform_device *pdev)
220 {
221 	struct mc13783_adc_priv *priv = platform_get_drvdata(pdev);
222 	unsigned flags = mc13xxx_get_flags(priv->mc13xxx);
223 
224 	return flags & MC13XXX_USE_TOUCHSCREEN;
225 }
226 
227 static int __init mc13783_adc_probe(struct platform_device *pdev)
228 {
229 	struct mc13783_adc_priv *priv;
230 	int ret;
231 	const struct platform_device_id *id = platform_get_device_id(pdev);
232 	char *dash;
233 
234 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
235 	if (!priv)
236 		return -ENOMEM;
237 
238 	priv->mc13xxx = dev_get_drvdata(pdev->dev.parent);
239 	snprintf(priv->name, ARRAY_SIZE(priv->name), "%s", id->name);
240 	dash = strchr(priv->name, '-');
241 	if (dash)
242 		*dash = '\0';
243 
244 	platform_set_drvdata(pdev, priv);
245 
246 	/* Register sysfs hooks */
247 	ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_base);
248 	if (ret)
249 		return ret;
250 
251 	if (id->driver_data & MC13783_ADC_16CHANS) {
252 		ret = sysfs_create_group(&pdev->dev.kobj,
253 				&mc13783_group_16chans);
254 		if (ret)
255 			goto out_err_create_16chans;
256 	}
257 
258 	if (!mc13783_adc_use_touchscreen(pdev)) {
259 		ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_ts);
260 		if (ret)
261 			goto out_err_create_ts;
262 	}
263 
264 	priv->hwmon_dev = hwmon_device_register(&pdev->dev);
265 	if (IS_ERR(priv->hwmon_dev)) {
266 		ret = PTR_ERR(priv->hwmon_dev);
267 		dev_err(&pdev->dev,
268 				"hwmon_device_register failed with %d.\n", ret);
269 		goto out_err_register;
270 	}
271 
272 	return 0;
273 
274 out_err_register:
275 
276 	if (!mc13783_adc_use_touchscreen(pdev))
277 		sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts);
278 out_err_create_ts:
279 
280 	if (id->driver_data & MC13783_ADC_16CHANS)
281 		sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans);
282 out_err_create_16chans:
283 
284 	sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base);
285 	return ret;
286 }
287 
288 static void mc13783_adc_remove(struct platform_device *pdev)
289 {
290 	struct mc13783_adc_priv *priv = platform_get_drvdata(pdev);
291 	kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
292 
293 	hwmon_device_unregister(priv->hwmon_dev);
294 
295 	if (!mc13783_adc_use_touchscreen(pdev))
296 		sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts);
297 
298 	if (driver_data & MC13783_ADC_16CHANS)
299 		sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans);
300 
301 	sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base);
302 }
303 
304 static const struct platform_device_id mc13783_adc_idtable[] = {
305 	{
306 		.name = "mc13783-adc",
307 		.driver_data = MC13783_ADC_16CHANS,
308 	}, {
309 		.name = "mc13892-adc",
310 		.driver_data = MC13783_ADC_BPDIV2,
311 	}, {
312 		/* sentinel */
313 	}
314 };
315 MODULE_DEVICE_TABLE(platform, mc13783_adc_idtable);
316 
317 static struct platform_driver mc13783_adc_driver = {
318 	.remove_new	= mc13783_adc_remove,
319 	.driver		= {
320 		.name	= DRIVER_NAME,
321 	},
322 	.id_table	= mc13783_adc_idtable,
323 };
324 
325 module_platform_driver_probe(mc13783_adc_driver, mc13783_adc_probe);
326 
327 MODULE_DESCRIPTION("MC13783 ADC driver");
328 MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
329 MODULE_LICENSE("GPL");
330