PageRenderTime 33ms CodeModel.GetById 17ms app.highlight 13ms RepoModel.GetById 1ms app.codeStats 0ms

/drivers/regulator/max1586.c

http://github.com/mirrors/linux
C | 316 lines | 229 code | 53 blank | 34 comment | 22 complexity | 24f2a78a0ac73ca53cbf89fad9f826ea MD5 | raw file
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * max1586.c  --  Voltage and current regulation for the Maxim 1586
  4 *
  5 * Copyright (C) 2008 Robert Jarzmik
  6 */
  7#include <linux/module.h>
  8#include <linux/err.h>
  9#include <linux/i2c.h>
 10#include <linux/platform_device.h>
 11#include <linux/regulator/driver.h>
 12#include <linux/slab.h>
 13#include <linux/regulator/max1586.h>
 14#include <linux/of_device.h>
 15#include <linux/regulator/of_regulator.h>
 16
 17#define MAX1586_V3_MAX_VSEL 31
 18#define MAX1586_V6_MAX_VSEL 3
 19
 20#define MAX1586_V3_MIN_UV   700000
 21#define MAX1586_V3_MAX_UV  1475000
 22
 23#define MAX1586_V6_MIN_UV        0
 24#define MAX1586_V6_MAX_UV  3000000
 25
 26#define I2C_V3_SELECT (0 << 5)
 27#define I2C_V6_SELECT (1 << 5)
 28
 29struct max1586_data {
 30	struct i2c_client *client;
 31
 32	/* min/max V3 voltage */
 33	unsigned int min_uV;
 34	unsigned int max_uV;
 35
 36	unsigned int v3_curr_sel;
 37	unsigned int v6_curr_sel;
 38};
 39
 40/*
 41 * V6 voltage
 42 * On I2C bus, sending a "x" byte to the max1586 means :
 43 *   set V6 to either 0V, 1.8V, 2.5V, 3V depending on (x & 0x3)
 44 * As regulator framework doesn't accept voltages to be 0V, we use 1uV.
 45 */
 46static const unsigned int v6_voltages_uv[] = { 1, 1800000, 2500000, 3000000 };
 47
 48/*
 49 * V3 voltage
 50 * On I2C bus, sending a "x" byte to the max1586 means :
 51 *   set V3 to 0.700V + (x & 0x1f) * 0.025V
 52 * This voltage can be increased by external resistors
 53 * R24 and R25=100kOhm as described in the data sheet.
 54 * The gain is approximately: 1 + R24/R25 + R24/185.5kOhm
 55 */
 56static int max1586_v3_get_voltage_sel(struct regulator_dev *rdev)
 57{
 58	struct max1586_data *max1586 = rdev_get_drvdata(rdev);
 59
 60	return max1586->v3_curr_sel;
 61}
 62
 63static int max1586_v3_set_voltage_sel(struct regulator_dev *rdev,
 64				      unsigned selector)
 65{
 66	struct max1586_data *max1586 = rdev_get_drvdata(rdev);
 67	struct i2c_client *client = max1586->client;
 68	int ret;
 69	u8 v3_prog;
 70
 71	dev_dbg(&client->dev, "changing voltage v3 to %dmv\n",
 72		regulator_list_voltage_linear(rdev, selector) / 1000);
 73
 74	v3_prog = I2C_V3_SELECT | (u8) selector;
 75	ret = i2c_smbus_write_byte(client, v3_prog);
 76	if (ret)
 77		return ret;
 78
 79	max1586->v3_curr_sel = selector;
 80
 81	return 0;
 82}
 83
 84static int max1586_v6_get_voltage_sel(struct regulator_dev *rdev)
 85{
 86	struct max1586_data *max1586 = rdev_get_drvdata(rdev);
 87
 88	return max1586->v6_curr_sel;
 89}
 90
 91static int max1586_v6_set_voltage_sel(struct regulator_dev *rdev,
 92				      unsigned int selector)
 93{
 94	struct max1586_data *max1586 = rdev_get_drvdata(rdev);
 95	struct i2c_client *client = max1586->client;
 96	u8 v6_prog;
 97	int ret;
 98
 99	dev_dbg(&client->dev, "changing voltage v6 to %dmv\n",
100		rdev->desc->volt_table[selector] / 1000);
101
102	v6_prog = I2C_V6_SELECT | (u8) selector;
103	ret = i2c_smbus_write_byte(client, v6_prog);
104	if (ret)
105		return ret;
106
107	max1586->v6_curr_sel = selector;
108
109	return 0;
110}
111
112/*
113 * The Maxim 1586 controls V3 and V6 voltages, but offers no way of reading back
114 * the set up value.
115 */
116static const struct regulator_ops max1586_v3_ops = {
117	.get_voltage_sel = max1586_v3_get_voltage_sel,
118	.set_voltage_sel = max1586_v3_set_voltage_sel,
119	.list_voltage = regulator_list_voltage_linear,
120	.map_voltage = regulator_map_voltage_linear,
121};
122
123static const struct regulator_ops max1586_v6_ops = {
124	.get_voltage_sel = max1586_v6_get_voltage_sel,
125	.set_voltage_sel = max1586_v6_set_voltage_sel,
126	.list_voltage = regulator_list_voltage_table,
127};
128
129static struct regulator_desc max1586_reg[] = {
130	{
131		.name = "Output_V3",
132		.id = MAX1586_V3,
133		.ops = &max1586_v3_ops,
134		.type = REGULATOR_VOLTAGE,
135		.n_voltages = MAX1586_V3_MAX_VSEL + 1,
136		.owner = THIS_MODULE,
137	},
138	{
139		.name = "Output_V6",
140		.id = MAX1586_V6,
141		.ops = &max1586_v6_ops,
142		.type = REGULATOR_VOLTAGE,
143		.n_voltages = MAX1586_V6_MAX_VSEL + 1,
144		.volt_table = v6_voltages_uv,
145		.owner = THIS_MODULE,
146	},
147};
148
149static int of_get_max1586_platform_data(struct device *dev,
150				 struct max1586_platform_data *pdata)
151{
152	struct max1586_subdev_data *sub;
153	struct of_regulator_match rmatch[ARRAY_SIZE(max1586_reg)] = { };
154	struct device_node *np = dev->of_node;
155	int i, matched;
156
157	if (of_property_read_u32(np, "v3-gain",
158				 &pdata->v3_gain) < 0) {
159		dev_err(dev, "%pOF has no 'v3-gain' property\n", np);
160		return -EINVAL;
161	}
162
163	np = of_get_child_by_name(np, "regulators");
164	if (!np) {
165		dev_err(dev, "missing 'regulators' subnode in DT\n");
166		return -EINVAL;
167	}
168
169	for (i = 0; i < ARRAY_SIZE(rmatch); i++)
170		rmatch[i].name = max1586_reg[i].name;
171
172	matched = of_regulator_match(dev, np, rmatch, ARRAY_SIZE(rmatch));
173	of_node_put(np);
174	/*
175	 * If matched is 0, ie. neither Output_V3 nor Output_V6 have been found,
176	 * return 0, which signals the normal situation where no subregulator is
177	 * available. This is normal because the max1586 doesn't provide any
178	 * readback support, so the subregulators can't report any status
179	 * anyway.  If matched < 0, return the error.
180	 */
181	if (matched <= 0)
182		return matched;
183
184	pdata->subdevs = devm_kcalloc(dev,
185				      matched,
186				      sizeof(struct max1586_subdev_data),
187				      GFP_KERNEL);
188	if (!pdata->subdevs)
189		return -ENOMEM;
190
191	pdata->num_subdevs = matched;
192	sub = pdata->subdevs;
193
194	for (i = 0; i < matched; i++) {
195		sub->id = i;
196		sub->name = rmatch[i].of_node->name;
197		sub->platform_data = rmatch[i].init_data;
198		sub++;
199	}
200
201	return 0;
202}
203
204static const struct of_device_id max1586_of_match[] = {
205	{ .compatible = "maxim,max1586", },
206	{},
207};
208MODULE_DEVICE_TABLE(of, max1586_of_match);
209
210static int max1586_pmic_probe(struct i2c_client *client,
211					const struct i2c_device_id *i2c_id)
212{
213	struct max1586_platform_data *pdata, pdata_of;
214	struct regulator_config config = { };
215	struct max1586_data *max1586;
216	int i, id, ret;
217	const struct of_device_id *match;
218
219	pdata = dev_get_platdata(&client->dev);
220	if (client->dev.of_node && !pdata) {
221		match = of_match_device(of_match_ptr(max1586_of_match),
222					&client->dev);
223		if (!match) {
224			dev_err(&client->dev, "Error: No device match found\n");
225			return -ENODEV;
226		}
227		ret = of_get_max1586_platform_data(&client->dev, &pdata_of);
228		if (ret < 0)
229			return ret;
230		pdata = &pdata_of;
231	}
232
233	max1586 = devm_kzalloc(&client->dev, sizeof(struct max1586_data),
234			GFP_KERNEL);
235	if (!max1586)
236		return -ENOMEM;
237
238	max1586->client = client;
239
240	if (!pdata->v3_gain)
241		return -EINVAL;
242
243	max1586->min_uV = MAX1586_V3_MIN_UV / 1000 * pdata->v3_gain / 1000;
244	max1586->max_uV = MAX1586_V3_MAX_UV / 1000 * pdata->v3_gain / 1000;
245
246	/* Set curr_sel to default voltage on power-up */
247	max1586->v3_curr_sel = 24; /* 1.3V */
248	max1586->v6_curr_sel = 0;
249
250	for (i = 0; i < pdata->num_subdevs && i <= MAX1586_V6; i++) {
251		struct regulator_dev *rdev;
252
253		id = pdata->subdevs[i].id;
254		if (!pdata->subdevs[i].platform_data)
255			continue;
256		if (id < MAX1586_V3 || id > MAX1586_V6) {
257			dev_err(&client->dev, "invalid regulator id %d\n", id);
258			return -EINVAL;
259		}
260
261		if (id == MAX1586_V3) {
262			max1586_reg[id].min_uV = max1586->min_uV;
263			max1586_reg[id].uV_step =
264					(max1586->max_uV - max1586->min_uV) /
265					MAX1586_V3_MAX_VSEL;
266		}
267
268		config.dev = &client->dev;
269		config.init_data = pdata->subdevs[i].platform_data;
270		config.driver_data = max1586;
271
272		rdev = devm_regulator_register(&client->dev,
273						  &max1586_reg[id], &config);
274		if (IS_ERR(rdev)) {
275			dev_err(&client->dev, "failed to register %s\n",
276				max1586_reg[id].name);
277			return PTR_ERR(rdev);
278		}
279	}
280
281	i2c_set_clientdata(client, max1586);
282	dev_info(&client->dev, "Maxim 1586 regulator driver loaded\n");
283	return 0;
284}
285
286static const struct i2c_device_id max1586_id[] = {
287	{ "max1586", 0 },
288	{ }
289};
290MODULE_DEVICE_TABLE(i2c, max1586_id);
291
292static struct i2c_driver max1586_pmic_driver = {
293	.probe = max1586_pmic_probe,
294	.driver		= {
295		.name	= "max1586",
296		.of_match_table = of_match_ptr(max1586_of_match),
297	},
298	.id_table	= max1586_id,
299};
300
301static int __init max1586_pmic_init(void)
302{
303	return i2c_add_driver(&max1586_pmic_driver);
304}
305subsys_initcall(max1586_pmic_init);
306
307static void __exit max1586_pmic_exit(void)
308{
309	i2c_del_driver(&max1586_pmic_driver);
310}
311module_exit(max1586_pmic_exit);
312
313/* Module information */
314MODULE_DESCRIPTION("MAXIM 1586 voltage regulator driver");
315MODULE_AUTHOR("Robert Jarzmik");
316MODULE_LICENSE("GPL");