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v3.1
  1/*
  2 * max8952.c - Voltage and current regulation for the Maxim 8952
  3 *
  4 * Copyright (C) 2010 Samsung Electronics
  5 * MyungJoo Ham <myungjoo.ham@samsung.com>
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License as published by
  9 * the Free Software Foundation; either version 2 of the License, or
 10 * (at your option) any later version.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with this program; if not, write to the Free Software
 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 20 */
 21
 22#include <linux/module.h>
 23#include <linux/init.h>
 24#include <linux/i2c.h>
 25#include <linux/err.h>
 26#include <linux/platform_device.h>
 27#include <linux/regulator/driver.h>
 28#include <linux/regulator/max8952.h>
 29#include <linux/mutex.h>
 30#include <linux/gpio.h>
 31#include <linux/io.h>
 
 
 
 32#include <linux/slab.h>
 33
 34/* Registers */
 35enum {
 36	MAX8952_REG_MODE0,
 37	MAX8952_REG_MODE1,
 38	MAX8952_REG_MODE2,
 39	MAX8952_REG_MODE3,
 40	MAX8952_REG_CONTROL,
 41	MAX8952_REG_SYNC,
 42	MAX8952_REG_RAMP,
 43	MAX8952_REG_CHIP_ID1,
 44	MAX8952_REG_CHIP_ID2,
 45};
 46
 47struct max8952_data {
 48	struct i2c_client	*client;
 49	struct device		*dev;
 50	struct mutex		mutex;
 51	struct max8952_platform_data *pdata;
 52	struct regulator_dev	*rdev;
 53
 54	bool vid0;
 55	bool vid1;
 56	bool en;
 57};
 58
 59static int max8952_read_reg(struct max8952_data *max8952, u8 reg)
 60{
 61	int ret = i2c_smbus_read_byte_data(max8952->client, reg);
 
 62	if (ret > 0)
 63		ret &= 0xff;
 64
 65	return ret;
 66}
 67
 68static int max8952_write_reg(struct max8952_data *max8952,
 69		u8 reg, u8 value)
 70{
 71	return i2c_smbus_write_byte_data(max8952->client, reg, value);
 72}
 73
 74static int max8952_voltage(struct max8952_data *max8952, u8 mode)
 75{
 76	return (max8952->pdata->dvs_mode[mode] * 10 + 770) * 1000;
 77}
 78
 79static int max8952_list_voltage(struct regulator_dev *rdev,
 80		unsigned int selector)
 81{
 82	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
 83
 84	if (rdev_get_id(rdev) != 0)
 85		return -EINVAL;
 86
 87	return max8952_voltage(max8952, selector);
 88}
 89
 90static int max8952_is_enabled(struct regulator_dev *rdev)
 91{
 92	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
 93	return max8952->en;
 94}
 95
 96static int max8952_enable(struct regulator_dev *rdev)
 97{
 98	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
 99
100	/* If not valid, assume "ALWAYS_HIGH" */
101	if (gpio_is_valid(max8952->pdata->gpio_en))
102		gpio_set_value(max8952->pdata->gpio_en, 1);
103
104	max8952->en = true;
105	return 0;
106}
107
108static int max8952_disable(struct regulator_dev *rdev)
109{
110	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
111
112	/* If not valid, assume "ALWAYS_HIGH" -> not permitted */
113	if (gpio_is_valid(max8952->pdata->gpio_en))
114		gpio_set_value(max8952->pdata->gpio_en, 0);
115	else
116		return -EPERM;
117
118	max8952->en = false;
119	return 0;
120}
121
122static int max8952_get_voltage(struct regulator_dev *rdev)
123{
124	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
125	u8 vid = 0;
126
127	if (max8952->vid0)
128		vid += 1;
129	if (max8952->vid1)
130		vid += 2;
131
132	return max8952_voltage(max8952, vid);
133}
134
135static int max8952_set_voltage(struct regulator_dev *rdev,
136			       int min_uV, int max_uV, unsigned *selector)
137{
138	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
139	s8 vid = -1, i;
140
141	if (!gpio_is_valid(max8952->pdata->gpio_vid0) ||
142			!gpio_is_valid(max8952->pdata->gpio_vid1)) {
143		/* DVS not supported */
144		return -EPERM;
145	}
146
147	for (i = 0; i < MAX8952_NUM_DVS_MODE; i++) {
148		int volt = max8952_voltage(max8952, i);
149
150		/* Set the voltage as low as possible within the range */
151		if (volt <= max_uV && volt >= min_uV)
152			if (vid == -1 || max8952_voltage(max8952, vid) > volt)
153				vid = i;
154	}
155
156	if (vid >= 0 && vid < MAX8952_NUM_DVS_MODE) {
157		max8952->vid0 = (vid % 2 == 1);
158		max8952->vid1 = (((vid >> 1) % 2) == 1);
159		*selector = vid;
160		gpio_set_value(max8952->pdata->gpio_vid0, max8952->vid0);
161		gpio_set_value(max8952->pdata->gpio_vid1, max8952->vid1);
162	} else
163		return -EINVAL;
164
165	return 0;
166}
167
168static struct regulator_ops max8952_ops = {
169	.list_voltage		= max8952_list_voltage,
170	.is_enabled		= max8952_is_enabled,
171	.enable			= max8952_enable,
172	.disable		= max8952_disable,
173	.get_voltage		= max8952_get_voltage,
174	.set_voltage		= max8952_set_voltage,
175	.set_suspend_disable	= max8952_disable,
176};
177
178static struct regulator_desc regulator = {
179	.name		= "MAX8952_VOUT",
180	.id		= 0,
181	.n_voltages	= MAX8952_NUM_DVS_MODE,
182	.ops		= &max8952_ops,
183	.type		= REGULATOR_VOLTAGE,
184	.owner		= THIS_MODULE,
185};
186
187static int __devinit max8952_pmic_probe(struct i2c_client *client,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
188		const struct i2c_device_id *i2c_id)
189{
190	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
191	struct max8952_platform_data *pdata = client->dev.platform_data;
 
192	struct max8952_data *max8952;
 
193
194	int ret = 0, err = 0;
195
 
 
 
196	if (!pdata) {
197		dev_err(&client->dev, "Require the platform data\n");
198		return -EINVAL;
199	}
200
201	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
202		return -EIO;
203
204	max8952 = kzalloc(sizeof(struct max8952_data), GFP_KERNEL);
 
205	if (!max8952)
206		return -ENOMEM;
207
208	max8952->client = client;
209	max8952->dev = &client->dev;
210	max8952->pdata = pdata;
211	mutex_init(&max8952->mutex);
212
213	max8952->rdev = regulator_register(&regulator, max8952->dev,
214			&pdata->reg_data, max8952);
215
216	if (IS_ERR(max8952->rdev)) {
217		ret = PTR_ERR(max8952->rdev);
218		dev_err(max8952->dev, "regulator init failed (%d)\n", ret);
219		goto err_reg;
220	}
221
222	max8952->en = !!(pdata->reg_data.constraints.boot_on);
223	max8952->vid0 = (pdata->default_mode % 2) == 1;
224	max8952->vid1 = ((pdata->default_mode >> 1) % 2) == 1;
225
226	if (gpio_is_valid(pdata->gpio_en)) {
227		if (!gpio_request(pdata->gpio_en, "MAX8952 EN"))
228			gpio_direction_output(pdata->gpio_en, max8952->en);
229		else
230			err = 1;
231	} else
232		err = 2;
233
234	if (err) {
235		dev_info(max8952->dev, "EN gpio invalid: assume that EN"
236				"is always High\n");
237		max8952->en = 1;
238		pdata->gpio_en = -1; /* Mark invalid */
 
 
 
 
 
 
 
 
 
 
239	}
240
241	err = 0;
 
242
243	if (gpio_is_valid(pdata->gpio_vid0) &&
244			gpio_is_valid(pdata->gpio_vid1)) {
245		if (!gpio_request(pdata->gpio_vid0, "MAX8952 VID0"))
246			gpio_direction_output(pdata->gpio_vid0,
247					(pdata->default_mode) % 2);
248		else
249			err = 1;
250
251		if (!gpio_request(pdata->gpio_vid1, "MAX8952 VID1"))
252			gpio_direction_output(pdata->gpio_vid1,
253				(pdata->default_mode >> 1) % 2);
254		else {
255			if (!err)
256				gpio_free(pdata->gpio_vid0);
257			err = 2;
258		}
259
260	} else
261		err = 3;
262
263	if (err) {
264		dev_warn(max8952->dev, "VID0/1 gpio invalid: "
265				"DVS not available.\n");
266		max8952->vid0 = 0;
267		max8952->vid1 = 0;
268		/* Mark invalid */
269		pdata->gpio_vid0 = -1;
270		pdata->gpio_vid1 = -1;
271
272		/* Disable Pulldown of EN only */
273		max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x60);
274
275		dev_err(max8952->dev, "DVS modes disabled because VID0 and VID1"
276				" do not have proper controls.\n");
277	} else {
278		/*
279		 * Disable Pulldown on EN, VID0, VID1 to reduce
280		 * leakage current of MAX8952 assuming that MAX8952
281		 * is turned on (EN==1). Note that without having VID0/1
282		 * properly connected, turning pulldown off can be
283		 * problematic. Thus, turn this off only when they are
284		 * controllable by GPIO.
285		 */
286		max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x0);
287	}
288
289	max8952_write_reg(max8952, MAX8952_REG_MODE0,
290			(max8952_read_reg(max8952,
291					  MAX8952_REG_MODE0) & 0xC0) |
292			(pdata->dvs_mode[0] & 0x3F));
293	max8952_write_reg(max8952, MAX8952_REG_MODE1,
294			(max8952_read_reg(max8952,
295					  MAX8952_REG_MODE1) & 0xC0) |
296			(pdata->dvs_mode[1] & 0x3F));
297	max8952_write_reg(max8952, MAX8952_REG_MODE2,
298			(max8952_read_reg(max8952,
299					  MAX8952_REG_MODE2) & 0xC0) |
300			(pdata->dvs_mode[2] & 0x3F));
301	max8952_write_reg(max8952, MAX8952_REG_MODE3,
302			(max8952_read_reg(max8952,
303					  MAX8952_REG_MODE3) & 0xC0) |
304			(pdata->dvs_mode[3] & 0x3F));
305
306	max8952_write_reg(max8952, MAX8952_REG_SYNC,
307			(max8952_read_reg(max8952, MAX8952_REG_SYNC) & 0x3F) |
308			((pdata->sync_freq & 0x3) << 6));
309	max8952_write_reg(max8952, MAX8952_REG_RAMP,
310			(max8952_read_reg(max8952, MAX8952_REG_RAMP) & 0x1F) |
311			((pdata->ramp_speed & 0x7) << 5));
312
313	i2c_set_clientdata(client, max8952);
314
315	return 0;
316
317err_reg:
318	kfree(max8952);
319	return ret;
320}
321
322static int __devexit max8952_pmic_remove(struct i2c_client *client)
323{
324	struct max8952_data *max8952 = i2c_get_clientdata(client);
325	struct max8952_platform_data *pdata = max8952->pdata;
326	struct regulator_dev *rdev = max8952->rdev;
327
328	regulator_unregister(rdev);
329
330	gpio_free(pdata->gpio_vid0);
331	gpio_free(pdata->gpio_vid1);
332	gpio_free(pdata->gpio_en);
333
334	kfree(max8952);
335	return 0;
336}
337
338static const struct i2c_device_id max8952_ids[] = {
339	{ "max8952", 0 },
340	{ },
341};
342MODULE_DEVICE_TABLE(i2c, max8952_ids);
343
344static struct i2c_driver max8952_pmic_driver = {
345	.probe		= max8952_pmic_probe,
346	.remove		= __devexit_p(max8952_pmic_remove),
347	.driver		= {
348		.name	= "max8952",
 
349	},
350	.id_table	= max8952_ids,
351};
352
353static int __init max8952_pmic_init(void)
354{
355	return i2c_add_driver(&max8952_pmic_driver);
356}
357subsys_initcall(max8952_pmic_init);
358
359static void __exit max8952_pmic_exit(void)
360{
361	i2c_del_driver(&max8952_pmic_driver);
362}
363module_exit(max8952_pmic_exit);
364
365MODULE_DESCRIPTION("MAXIM 8952 voltage regulator driver");
366MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
367MODULE_LICENSE("GPL");
v3.15
  1/*
  2 * max8952.c - Voltage and current regulation for the Maxim 8952
  3 *
  4 * Copyright (C) 2010 Samsung Electronics
  5 * MyungJoo Ham <myungjoo.ham@samsung.com>
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License as published by
  9 * the Free Software Foundation; either version 2 of the License, or
 10 * (at your option) any later version.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with this program; if not, write to the Free Software
 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 20 */
 21
 22#include <linux/module.h>
 23#include <linux/init.h>
 24#include <linux/i2c.h>
 25#include <linux/err.h>
 26#include <linux/platform_device.h>
 27#include <linux/regulator/driver.h>
 28#include <linux/regulator/max8952.h>
 
 29#include <linux/gpio.h>
 30#include <linux/io.h>
 31#include <linux/of.h>
 32#include <linux/of_gpio.h>
 33#include <linux/regulator/of_regulator.h>
 34#include <linux/slab.h>
 35
 36/* Registers */
 37enum {
 38	MAX8952_REG_MODE0,
 39	MAX8952_REG_MODE1,
 40	MAX8952_REG_MODE2,
 41	MAX8952_REG_MODE3,
 42	MAX8952_REG_CONTROL,
 43	MAX8952_REG_SYNC,
 44	MAX8952_REG_RAMP,
 45	MAX8952_REG_CHIP_ID1,
 46	MAX8952_REG_CHIP_ID2,
 47};
 48
 49struct max8952_data {
 50	struct i2c_client	*client;
 
 
 51	struct max8952_platform_data *pdata;
 
 52
 53	bool vid0;
 54	bool vid1;
 
 55};
 56
 57static int max8952_read_reg(struct max8952_data *max8952, u8 reg)
 58{
 59	int ret = i2c_smbus_read_byte_data(max8952->client, reg);
 60
 61	if (ret > 0)
 62		ret &= 0xff;
 63
 64	return ret;
 65}
 66
 67static int max8952_write_reg(struct max8952_data *max8952,
 68		u8 reg, u8 value)
 69{
 70	return i2c_smbus_write_byte_data(max8952->client, reg, value);
 71}
 72
 
 
 
 
 
 73static int max8952_list_voltage(struct regulator_dev *rdev,
 74		unsigned int selector)
 75{
 76	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
 77
 78	if (rdev_get_id(rdev) != 0)
 79		return -EINVAL;
 80
 81	return (max8952->pdata->dvs_mode[selector] * 10 + 770) * 1000;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 82}
 83
 84static int max8952_get_voltage_sel(struct regulator_dev *rdev)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 85{
 86	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
 87	u8 vid = 0;
 88
 89	if (max8952->vid0)
 90		vid += 1;
 91	if (max8952->vid1)
 92		vid += 2;
 93
 94	return vid;
 95}
 96
 97static int max8952_set_voltage_sel(struct regulator_dev *rdev,
 98				   unsigned selector)
 99{
100	struct max8952_data *max8952 = rdev_get_drvdata(rdev);
 
101
102	if (!gpio_is_valid(max8952->pdata->gpio_vid0) ||
103			!gpio_is_valid(max8952->pdata->gpio_vid1)) {
104		/* DVS not supported */
105		return -EPERM;
106	}
107
108	max8952->vid0 = selector & 0x1;
109	max8952->vid1 = (selector >> 1) & 0x1;
110	gpio_set_value(max8952->pdata->gpio_vid0, max8952->vid0);
111	gpio_set_value(max8952->pdata->gpio_vid1, max8952->vid1);
 
 
 
 
 
 
 
 
 
 
 
 
 
112
113	return 0;
114}
115
116static struct regulator_ops max8952_ops = {
117	.list_voltage		= max8952_list_voltage,
118	.get_voltage_sel	= max8952_get_voltage_sel,
119	.set_voltage_sel	= max8952_set_voltage_sel,
 
 
 
 
120};
121
122static const struct regulator_desc regulator = {
123	.name		= "MAX8952_VOUT",
124	.id		= 0,
125	.n_voltages	= MAX8952_NUM_DVS_MODE,
126	.ops		= &max8952_ops,
127	.type		= REGULATOR_VOLTAGE,
128	.owner		= THIS_MODULE,
129};
130
131#ifdef CONFIG_OF
132static struct of_device_id max8952_dt_match[] = {
133	{ .compatible = "maxim,max8952" },
134	{},
135};
136MODULE_DEVICE_TABLE(of, max8952_dt_match);
137
138static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
139{
140	struct max8952_platform_data *pd;
141	struct device_node *np = dev->of_node;
142	int ret;
143	int i;
144
145	pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
146	if (!pd)
147		return NULL;
148
149	pd->gpio_vid0 = of_get_named_gpio(np, "max8952,vid-gpios", 0);
150	pd->gpio_vid1 = of_get_named_gpio(np, "max8952,vid-gpios", 1);
151	pd->gpio_en = of_get_named_gpio(np, "max8952,en-gpio", 0);
152
153	if (of_property_read_u32(np, "max8952,default-mode", &pd->default_mode))
154		dev_warn(dev, "Default mode not specified, assuming 0\n");
155
156	ret = of_property_read_u32_array(np, "max8952,dvs-mode-microvolt",
157					pd->dvs_mode, ARRAY_SIZE(pd->dvs_mode));
158	if (ret) {
159		dev_err(dev, "max8952,dvs-mode-microvolt property not specified");
160		return NULL;
161	}
162
163	for (i = 0; i < ARRAY_SIZE(pd->dvs_mode); ++i) {
164		if (pd->dvs_mode[i] < 770000 || pd->dvs_mode[i] > 1400000) {
165			dev_err(dev, "DVS voltage %d out of range\n", i);
166			return NULL;
167		}
168		pd->dvs_mode[i] = (pd->dvs_mode[i] - 770000) / 10000;
169	}
170
171	if (of_property_read_u32(np, "max8952,sync-freq", &pd->sync_freq))
172		dev_warn(dev, "max8952,sync-freq property not specified, defaulting to 26MHz\n");
173
174	if (of_property_read_u32(np, "max8952,ramp-speed", &pd->ramp_speed))
175		dev_warn(dev, "max8952,ramp-speed property not specified, defaulting to 32mV/us\n");
176
177	pd->reg_data = of_get_regulator_init_data(dev, np);
178	if (!pd->reg_data) {
179		dev_err(dev, "Failed to parse regulator init data\n");
180		return NULL;
181	}
182
183	return pd;
184}
185#else
186static struct max8952_platform_data *max8952_parse_dt(struct device *dev)
187{
188	return NULL;
189}
190#endif
191
192static int max8952_pmic_probe(struct i2c_client *client,
193		const struct i2c_device_id *i2c_id)
194{
195	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
196	struct max8952_platform_data *pdata = dev_get_platdata(&client->dev);
197	struct regulator_config config = { };
198	struct max8952_data *max8952;
199	struct regulator_dev *rdev;
200
201	int ret = 0, err = 0;
202
203	if (client->dev.of_node)
204		pdata = max8952_parse_dt(&client->dev);
205
206	if (!pdata) {
207		dev_err(&client->dev, "Require the platform data\n");
208		return -EINVAL;
209	}
210
211	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
212		return -EIO;
213
214	max8952 = devm_kzalloc(&client->dev, sizeof(struct max8952_data),
215			       GFP_KERNEL);
216	if (!max8952)
217		return -ENOMEM;
218
219	max8952->client = client;
 
220	max8952->pdata = pdata;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
221
222	config.dev = &client->dev;
223	config.init_data = pdata->reg_data;
224	config.driver_data = max8952;
225	config.of_node = client->dev.of_node;
226
227	config.ena_gpio = pdata->gpio_en;
228	if (pdata->reg_data->constraints.boot_on)
229		config.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
230
231	rdev = devm_regulator_register(&client->dev, &regulator, &config);
232
233	if (IS_ERR(rdev)) {
234		ret = PTR_ERR(rdev);
235		dev_err(&client->dev, "regulator init failed (%d)\n", ret);
236		return ret;
237	}
238
239	max8952->vid0 = pdata->default_mode & 0x1;
240	max8952->vid1 = (pdata->default_mode >> 1) & 0x1;
241
242	if (gpio_is_valid(pdata->gpio_vid0) &&
243			gpio_is_valid(pdata->gpio_vid1)) {
244		if (!gpio_request(pdata->gpio_vid0, "MAX8952 VID0"))
245			gpio_direction_output(pdata->gpio_vid0,
246					(pdata->default_mode) & 0x1);
247		else
248			err = 1;
249
250		if (!gpio_request(pdata->gpio_vid1, "MAX8952 VID1"))
251			gpio_direction_output(pdata->gpio_vid1,
252				(pdata->default_mode >> 1) & 0x1);
253		else {
254			if (!err)
255				gpio_free(pdata->gpio_vid0);
256			err = 2;
257		}
258
259	} else
260		err = 3;
261
262	if (err) {
263		dev_warn(&client->dev, "VID0/1 gpio invalid: "
264				"DVS not available.\n");
265		max8952->vid0 = 0;
266		max8952->vid1 = 0;
267		/* Mark invalid */
268		pdata->gpio_vid0 = -1;
269		pdata->gpio_vid1 = -1;
270
271		/* Disable Pulldown of EN only */
272		max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x60);
273
274		dev_err(&client->dev, "DVS modes disabled because VID0 and VID1"
275				" do not have proper controls.\n");
276	} else {
277		/*
278		 * Disable Pulldown on EN, VID0, VID1 to reduce
279		 * leakage current of MAX8952 assuming that MAX8952
280		 * is turned on (EN==1). Note that without having VID0/1
281		 * properly connected, turning pulldown off can be
282		 * problematic. Thus, turn this off only when they are
283		 * controllable by GPIO.
284		 */
285		max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x0);
286	}
287
288	max8952_write_reg(max8952, MAX8952_REG_MODE0,
289			(max8952_read_reg(max8952,
290					  MAX8952_REG_MODE0) & 0xC0) |
291			(pdata->dvs_mode[0] & 0x3F));
292	max8952_write_reg(max8952, MAX8952_REG_MODE1,
293			(max8952_read_reg(max8952,
294					  MAX8952_REG_MODE1) & 0xC0) |
295			(pdata->dvs_mode[1] & 0x3F));
296	max8952_write_reg(max8952, MAX8952_REG_MODE2,
297			(max8952_read_reg(max8952,
298					  MAX8952_REG_MODE2) & 0xC0) |
299			(pdata->dvs_mode[2] & 0x3F));
300	max8952_write_reg(max8952, MAX8952_REG_MODE3,
301			(max8952_read_reg(max8952,
302					  MAX8952_REG_MODE3) & 0xC0) |
303			(pdata->dvs_mode[3] & 0x3F));
304
305	max8952_write_reg(max8952, MAX8952_REG_SYNC,
306			(max8952_read_reg(max8952, MAX8952_REG_SYNC) & 0x3F) |
307			((pdata->sync_freq & 0x3) << 6));
308	max8952_write_reg(max8952, MAX8952_REG_RAMP,
309			(max8952_read_reg(max8952, MAX8952_REG_RAMP) & 0x1F) |
310			((pdata->ramp_speed & 0x7) << 5));
311
312	i2c_set_clientdata(client, max8952);
313
314	return 0;
 
 
 
 
315}
316
317static int max8952_pmic_remove(struct i2c_client *client)
318{
319	struct max8952_data *max8952 = i2c_get_clientdata(client);
320	struct max8952_platform_data *pdata = max8952->pdata;
 
 
 
321
322	gpio_free(pdata->gpio_vid0);
323	gpio_free(pdata->gpio_vid1);
 
 
 
324	return 0;
325}
326
327static const struct i2c_device_id max8952_ids[] = {
328	{ "max8952", 0 },
329	{ },
330};
331MODULE_DEVICE_TABLE(i2c, max8952_ids);
332
333static struct i2c_driver max8952_pmic_driver = {
334	.probe		= max8952_pmic_probe,
335	.remove		= max8952_pmic_remove,
336	.driver		= {
337		.name	= "max8952",
338		.of_match_table = of_match_ptr(max8952_dt_match),
339	},
340	.id_table	= max8952_ids,
341};
342
343static int __init max8952_pmic_init(void)
344{
345	return i2c_add_driver(&max8952_pmic_driver);
346}
347subsys_initcall(max8952_pmic_init);
348
349static void __exit max8952_pmic_exit(void)
350{
351	i2c_del_driver(&max8952_pmic_driver);
352}
353module_exit(max8952_pmic_exit);
354
355MODULE_DESCRIPTION("MAXIM 8952 voltage regulator driver");
356MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
357MODULE_LICENSE("GPL");