Commit | Line | Data |
---|---|---|
202f4f53 MH |
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> | |
202f4f53 MH |
29 | #include <linux/gpio.h> |
30 | #include <linux/io.h> | |
3ff4aa95 TF |
31 | #include <linux/of.h> |
32 | #include <linux/of_gpio.h> | |
33 | #include <linux/regulator/of_regulator.h> | |
202f4f53 MH |
34 | #include <linux/slab.h> |
35 | ||
36 | /* Registers */ | |
37 | enum { | |
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 | ||
49 | struct max8952_data { | |
50 | struct i2c_client *client; | |
202f4f53 | 51 | struct max8952_platform_data *pdata; |
202f4f53 MH |
52 | |
53 | bool vid0; | |
54 | bool vid1; | |
202f4f53 MH |
55 | }; |
56 | ||
57 | static int max8952_read_reg(struct max8952_data *max8952, u8 reg) | |
58 | { | |
59 | int ret = i2c_smbus_read_byte_data(max8952->client, reg); | |
a5f8f963 | 60 | |
202f4f53 MH |
61 | if (ret > 0) |
62 | ret &= 0xff; | |
63 | ||
64 | return ret; | |
65 | } | |
66 | ||
67 | static 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 | ||
202f4f53 MH |
73 | static 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 | ||
b9b49af5 | 81 | return (max8952->pdata->dvs_mode[selector] * 10 + 770) * 1000; |
202f4f53 MH |
82 | } |
83 | ||
b9b49af5 | 84 | static int max8952_get_voltage_sel(struct regulator_dev *rdev) |
202f4f53 MH |
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 | ||
b9b49af5 | 94 | return vid; |
202f4f53 MH |
95 | } |
96 | ||
6ea67d04 AL |
97 | static int max8952_set_voltage_sel(struct regulator_dev *rdev, |
98 | unsigned selector) | |
202f4f53 MH |
99 | { |
100 | struct max8952_data *max8952 = rdev_get_drvdata(rdev); | |
202f4f53 MH |
101 | |
102 | if (!gpio_is_valid(max8952->pdata->gpio_vid0) || | |
e2cf3137 | 103 | !gpio_is_valid(max8952->pdata->gpio_vid1)) { |
202f4f53 MH |
104 | /* DVS not supported */ |
105 | return -EPERM; | |
106 | } | |
107 | ||
6ea67d04 AL |
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); | |
202f4f53 MH |
112 | |
113 | return 0; | |
114 | } | |
115 | ||
116 | static struct regulator_ops max8952_ops = { | |
117 | .list_voltage = max8952_list_voltage, | |
b9b49af5 | 118 | .get_voltage_sel = max8952_get_voltage_sel, |
6ea67d04 | 119 | .set_voltage_sel = max8952_set_voltage_sel, |
202f4f53 MH |
120 | }; |
121 | ||
bd6ff0d6 | 122 | static const struct regulator_desc regulator = { |
202f4f53 MH |
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 | ||
3ff4aa95 | 131 | #ifdef CONFIG_OF |
cfe6e333 | 132 | static const struct of_device_id max8952_dt_match[] = { |
3ff4aa95 TF |
133 | { .compatible = "maxim,max8952" }, |
134 | {}, | |
135 | }; | |
136 | MODULE_DEVICE_TABLE(of, max8952_dt_match); | |
137 | ||
138 | static 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); | |
7752d964 | 146 | if (!pd) |
3ff4aa95 | 147 | return NULL; |
3ff4aa95 TF |
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 | |
186 | static struct max8952_platform_data *max8952_parse_dt(struct device *dev) | |
187 | { | |
188 | return NULL; | |
189 | } | |
190 | #endif | |
191 | ||
a5023574 | 192 | static int max8952_pmic_probe(struct i2c_client *client, |
202f4f53 MH |
193 | const struct i2c_device_id *i2c_id) |
194 | { | |
195 | struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); | |
dff91d0b | 196 | struct max8952_platform_data *pdata = dev_get_platdata(&client->dev); |
c172708d | 197 | struct regulator_config config = { }; |
202f4f53 | 198 | struct max8952_data *max8952; |
b874f41c | 199 | struct regulator_dev *rdev; |
202f4f53 MH |
200 | |
201 | int ret = 0, err = 0; | |
202 | ||
3ff4aa95 TF |
203 | if (client->dev.of_node) |
204 | pdata = max8952_parse_dt(&client->dev); | |
205 | ||
202f4f53 MH |
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 | ||
372de4aa AL |
214 | max8952 = devm_kzalloc(&client->dev, sizeof(struct max8952_data), |
215 | GFP_KERNEL); | |
202f4f53 MH |
216 | if (!max8952) |
217 | return -ENOMEM; | |
218 | ||
219 | max8952->client = client; | |
202f4f53 | 220 | max8952->pdata = pdata; |
202f4f53 | 221 | |
b874f41c | 222 | config.dev = &client->dev; |
3ec6eb9c | 223 | config.init_data = pdata->reg_data; |
c172708d | 224 | config.driver_data = max8952; |
71622e15 | 225 | config.of_node = client->dev.of_node; |
c172708d | 226 | |
b669e0ad | 227 | config.ena_gpio = pdata->gpio_en; |
3ec6eb9c | 228 | if (pdata->reg_data->constraints.boot_on) |
b669e0ad AL |
229 | config.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH; |
230 | ||
b874f41c | 231 | rdev = devm_regulator_register(&client->dev, ®ulator, &config); |
b874f41c KK |
232 | if (IS_ERR(rdev)) { |
233 | ret = PTR_ERR(rdev); | |
234 | dev_err(&client->dev, "regulator init failed (%d)\n", ret); | |
372de4aa | 235 | return ret; |
da05738e | 236 | } |
202f4f53 | 237 | |
c8237f01 AL |
238 | max8952->vid0 = pdata->default_mode & 0x1; |
239 | max8952->vid1 = (pdata->default_mode >> 1) & 0x1; | |
202f4f53 | 240 | |
202f4f53 MH |
241 | if (gpio_is_valid(pdata->gpio_vid0) && |
242 | gpio_is_valid(pdata->gpio_vid1)) { | |
d7da152c AL |
243 | unsigned long gpio_flags; |
244 | ||
245 | gpio_flags = max8952->vid0 ? | |
246 | GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW; | |
247 | if (devm_gpio_request_one(&client->dev, pdata->gpio_vid0, | |
248 | gpio_flags, "MAX8952 VID0")) | |
202f4f53 MH |
249 | err = 1; |
250 | ||
d7da152c AL |
251 | gpio_flags = max8952->vid1 ? |
252 | GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW; | |
253 | if (devm_gpio_request_one(&client->dev, pdata->gpio_vid1, | |
254 | gpio_flags, "MAX8952 VID1")) | |
202f4f53 | 255 | err = 2; |
202f4f53 MH |
256 | } else |
257 | err = 3; | |
258 | ||
259 | if (err) { | |
b874f41c | 260 | dev_warn(&client->dev, "VID0/1 gpio invalid: " |
25985edc | 261 | "DVS not available.\n"); |
202f4f53 MH |
262 | max8952->vid0 = 0; |
263 | max8952->vid1 = 0; | |
264 | /* Mark invalid */ | |
265 | pdata->gpio_vid0 = -1; | |
266 | pdata->gpio_vid1 = -1; | |
267 | ||
268 | /* Disable Pulldown of EN only */ | |
269 | max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x60); | |
270 | ||
b874f41c | 271 | dev_err(&client->dev, "DVS modes disabled because VID0 and VID1" |
202f4f53 MH |
272 | " do not have proper controls.\n"); |
273 | } else { | |
274 | /* | |
275 | * Disable Pulldown on EN, VID0, VID1 to reduce | |
276 | * leakage current of MAX8952 assuming that MAX8952 | |
277 | * is turned on (EN==1). Note that without having VID0/1 | |
278 | * properly connected, turning pulldown off can be | |
279 | * problematic. Thus, turn this off only when they are | |
280 | * controllable by GPIO. | |
281 | */ | |
282 | max8952_write_reg(max8952, MAX8952_REG_CONTROL, 0x0); | |
283 | } | |
284 | ||
285 | max8952_write_reg(max8952, MAX8952_REG_MODE0, | |
286 | (max8952_read_reg(max8952, | |
287 | MAX8952_REG_MODE0) & 0xC0) | | |
288 | (pdata->dvs_mode[0] & 0x3F)); | |
289 | max8952_write_reg(max8952, MAX8952_REG_MODE1, | |
290 | (max8952_read_reg(max8952, | |
291 | MAX8952_REG_MODE1) & 0xC0) | | |
292 | (pdata->dvs_mode[1] & 0x3F)); | |
293 | max8952_write_reg(max8952, MAX8952_REG_MODE2, | |
294 | (max8952_read_reg(max8952, | |
295 | MAX8952_REG_MODE2) & 0xC0) | | |
296 | (pdata->dvs_mode[2] & 0x3F)); | |
297 | max8952_write_reg(max8952, MAX8952_REG_MODE3, | |
298 | (max8952_read_reg(max8952, | |
299 | MAX8952_REG_MODE3) & 0xC0) | | |
300 | (pdata->dvs_mode[3] & 0x3F)); | |
301 | ||
302 | max8952_write_reg(max8952, MAX8952_REG_SYNC, | |
303 | (max8952_read_reg(max8952, MAX8952_REG_SYNC) & 0x3F) | | |
304 | ((pdata->sync_freq & 0x3) << 6)); | |
305 | max8952_write_reg(max8952, MAX8952_REG_RAMP, | |
306 | (max8952_read_reg(max8952, MAX8952_REG_RAMP) & 0x1F) | | |
307 | ((pdata->ramp_speed & 0x7) << 5)); | |
308 | ||
309 | i2c_set_clientdata(client, max8952); | |
310 | ||
da05738e | 311 | return 0; |
202f4f53 MH |
312 | } |
313 | ||
202f4f53 MH |
314 | static const struct i2c_device_id max8952_ids[] = { |
315 | { "max8952", 0 }, | |
316 | { }, | |
317 | }; | |
318 | MODULE_DEVICE_TABLE(i2c, max8952_ids); | |
319 | ||
320 | static struct i2c_driver max8952_pmic_driver = { | |
321 | .probe = max8952_pmic_probe, | |
202f4f53 MH |
322 | .driver = { |
323 | .name = "max8952", | |
3ff4aa95 | 324 | .of_match_table = of_match_ptr(max8952_dt_match), |
202f4f53 MH |
325 | }, |
326 | .id_table = max8952_ids, | |
327 | }; | |
328 | ||
329 | static int __init max8952_pmic_init(void) | |
330 | { | |
331 | return i2c_add_driver(&max8952_pmic_driver); | |
332 | } | |
333 | subsys_initcall(max8952_pmic_init); | |
334 | ||
335 | static void __exit max8952_pmic_exit(void) | |
336 | { | |
337 | i2c_del_driver(&max8952_pmic_driver); | |
338 | } | |
339 | module_exit(max8952_pmic_exit); | |
340 | ||
341 | MODULE_DESCRIPTION("MAXIM 8952 voltage regulator driver"); | |
342 | MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); | |
343 | MODULE_LICENSE("GPL"); |