1 /* 2 * wm8994-regulator.c -- Regulator driver for the WM8994 3 * 4 * Copyright 2009 Wolfson Microelectronics PLC. 5 * 6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the 10 * Free Software Foundation; either version 2 of the License, or (at your 11 * option) any later version. 12 */ 13 14 #include <linux/module.h> 15 #include <linux/moduleparam.h> 16 #include <linux/init.h> 17 #include <linux/bitops.h> 18 #include <linux/err.h> 19 #include <linux/platform_device.h> 20 #include <linux/regulator/driver.h> 21 #include <linux/gpio.h> 22 #include <linux/slab.h> 23 24 #include <linux/mfd/wm8994/core.h> 25 #include <linux/mfd/wm8994/registers.h> 26 #include <linux/mfd/wm8994/pdata.h> 27 28 struct wm8994_ldo { 29 int enable; 30 bool is_enabled; 31 struct regulator_dev *regulator; 32 struct wm8994 *wm8994; 33 }; 34 35 #define WM8994_LDO1_MAX_SELECTOR 0x7 36 #define WM8994_LDO2_MAX_SELECTOR 0x3 37 38 static int wm8994_ldo_enable(struct regulator_dev *rdev) 39 { 40 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 41 42 /* If we have no soft control assume that the LDO is always enabled. */ 43 if (!ldo->enable) 44 return 0; 45 46 gpio_set_value_cansleep(ldo->enable, 1); 47 ldo->is_enabled = true; 48 49 return 0; 50 } 51 52 static int wm8994_ldo_disable(struct regulator_dev *rdev) 53 { 54 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 55 56 /* If we have no soft control assume that the LDO is always enabled. */ 57 if (!ldo->enable) 58 return -EINVAL; 59 60 gpio_set_value_cansleep(ldo->enable, 0); 61 ldo->is_enabled = false; 62 63 return 0; 64 } 65 66 static int wm8994_ldo_is_enabled(struct regulator_dev *rdev) 67 { 68 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 69 70 return ldo->is_enabled; 71 } 72 73 static int wm8994_ldo_enable_time(struct regulator_dev *rdev) 74 { 75 /* 3ms is fairly conservative but this shouldn't be too performance 76 * critical; can be tweaked per-system if required. */ 77 return 3000; 78 } 79 80 static int wm8994_ldo1_list_voltage(struct regulator_dev *rdev, 81 unsigned int selector) 82 { 83 if (selector > WM8994_LDO1_MAX_SELECTOR) 84 return -EINVAL; 85 86 return (selector * 100000) + 2400000; 87 } 88 89 static int wm8994_ldo1_get_voltage_sel(struct regulator_dev *rdev) 90 { 91 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 92 int val; 93 94 val = wm8994_reg_read(ldo->wm8994, WM8994_LDO_1); 95 if (val < 0) 96 return val; 97 98 return (val & WM8994_LDO1_VSEL_MASK) >> WM8994_LDO1_VSEL_SHIFT; 99 } 100 101 static int wm8994_ldo1_set_voltage(struct regulator_dev *rdev, 102 int min_uV, int max_uV, unsigned *s) 103 { 104 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 105 int selector, v; 106 107 selector = (min_uV - 2400000) / 100000; 108 v = wm8994_ldo1_list_voltage(rdev, selector); 109 if (v < 0 || v > max_uV) 110 return -EINVAL; 111 112 *s = selector; 113 selector <<= WM8994_LDO1_VSEL_SHIFT; 114 115 return wm8994_set_bits(ldo->wm8994, WM8994_LDO_1, 116 WM8994_LDO1_VSEL_MASK, selector); 117 } 118 119 static struct regulator_ops wm8994_ldo1_ops = { 120 .enable = wm8994_ldo_enable, 121 .disable = wm8994_ldo_disable, 122 .is_enabled = wm8994_ldo_is_enabled, 123 .enable_time = wm8994_ldo_enable_time, 124 125 .list_voltage = wm8994_ldo1_list_voltage, 126 .get_voltage_sel = wm8994_ldo1_get_voltage_sel, 127 .set_voltage = wm8994_ldo1_set_voltage, 128 }; 129 130 static int wm8994_ldo2_list_voltage(struct regulator_dev *rdev, 131 unsigned int selector) 132 { 133 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 134 135 if (selector > WM8994_LDO2_MAX_SELECTOR) 136 return -EINVAL; 137 138 switch (ldo->wm8994->type) { 139 case WM8994: 140 return (selector * 100000) + 900000; 141 case WM8958: 142 return (selector * 100000) + 1000000; 143 case WM1811: 144 switch (selector) { 145 case 0: 146 return -EINVAL; 147 default: 148 return (selector * 100000) + 950000; 149 } 150 break; 151 default: 152 return -EINVAL; 153 } 154 } 155 156 static int wm8994_ldo2_get_voltage_sel(struct regulator_dev *rdev) 157 { 158 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 159 int val; 160 161 val = wm8994_reg_read(ldo->wm8994, WM8994_LDO_2); 162 if (val < 0) 163 return val; 164 165 return (val & WM8994_LDO2_VSEL_MASK) >> WM8994_LDO2_VSEL_SHIFT; 166 } 167 168 static int wm8994_ldo2_set_voltage(struct regulator_dev *rdev, 169 int min_uV, int max_uV, unsigned *s) 170 { 171 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 172 int selector, v; 173 174 switch (ldo->wm8994->type) { 175 case WM8994: 176 selector = (min_uV - 900000) / 100000; 177 break; 178 case WM8958: 179 selector = (min_uV - 1000000) / 100000; 180 break; 181 case WM1811: 182 selector = (min_uV - 950000) / 100000; 183 if (selector == 0) 184 selector = 1; 185 break; 186 default: 187 return -EINVAL; 188 } 189 190 v = wm8994_ldo2_list_voltage(rdev, selector); 191 if (v < 0 || v > max_uV) 192 return -EINVAL; 193 194 *s = selector; 195 selector <<= WM8994_LDO2_VSEL_SHIFT; 196 197 return wm8994_set_bits(ldo->wm8994, WM8994_LDO_2, 198 WM8994_LDO2_VSEL_MASK, selector); 199 } 200 201 static struct regulator_ops wm8994_ldo2_ops = { 202 .enable = wm8994_ldo_enable, 203 .disable = wm8994_ldo_disable, 204 .is_enabled = wm8994_ldo_is_enabled, 205 .enable_time = wm8994_ldo_enable_time, 206 207 .list_voltage = wm8994_ldo2_list_voltage, 208 .get_voltage_sel = wm8994_ldo2_get_voltage_sel, 209 .set_voltage = wm8994_ldo2_set_voltage, 210 }; 211 212 static struct regulator_desc wm8994_ldo_desc[] = { 213 { 214 .name = "LDO1", 215 .id = 1, 216 .type = REGULATOR_VOLTAGE, 217 .n_voltages = WM8994_LDO1_MAX_SELECTOR + 1, 218 .ops = &wm8994_ldo1_ops, 219 .owner = THIS_MODULE, 220 }, 221 { 222 .name = "LDO2", 223 .id = 2, 224 .type = REGULATOR_VOLTAGE, 225 .n_voltages = WM8994_LDO2_MAX_SELECTOR + 1, 226 .ops = &wm8994_ldo2_ops, 227 .owner = THIS_MODULE, 228 }, 229 }; 230 231 static __devinit int wm8994_ldo_probe(struct platform_device *pdev) 232 { 233 struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent); 234 struct wm8994_pdata *pdata = wm8994->dev->platform_data; 235 int id = pdev->id % ARRAY_SIZE(pdata->ldo); 236 struct wm8994_ldo *ldo; 237 int ret; 238 239 dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1); 240 241 if (!pdata) 242 return -ENODEV; 243 244 ldo = kzalloc(sizeof(struct wm8994_ldo), GFP_KERNEL); 245 if (ldo == NULL) { 246 dev_err(&pdev->dev, "Unable to allocate private data\n"); 247 return -ENOMEM; 248 } 249 250 ldo->wm8994 = wm8994; 251 252 if (pdata->ldo[id].enable && gpio_is_valid(pdata->ldo[id].enable)) { 253 ldo->enable = pdata->ldo[id].enable; 254 255 ret = gpio_request(ldo->enable, "WM8994 LDO enable"); 256 if (ret < 0) { 257 dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", 258 ret); 259 goto err; 260 } 261 262 ret = gpio_direction_output(ldo->enable, ldo->is_enabled); 263 if (ret < 0) { 264 dev_err(&pdev->dev, "Failed to set GPIO up: %d\n", 265 ret); 266 goto err_gpio; 267 } 268 } else 269 ldo->is_enabled = true; 270 271 ldo->regulator = regulator_register(&wm8994_ldo_desc[id], &pdev->dev, 272 pdata->ldo[id].init_data, ldo); 273 if (IS_ERR(ldo->regulator)) { 274 ret = PTR_ERR(ldo->regulator); 275 dev_err(wm8994->dev, "Failed to register LDO%d: %d\n", 276 id + 1, ret); 277 goto err_gpio; 278 } 279 280 platform_set_drvdata(pdev, ldo); 281 282 return 0; 283 284 err_gpio: 285 if (gpio_is_valid(ldo->enable)) 286 gpio_free(ldo->enable); 287 err: 288 kfree(ldo); 289 return ret; 290 } 291 292 static __devexit int wm8994_ldo_remove(struct platform_device *pdev) 293 { 294 struct wm8994_ldo *ldo = platform_get_drvdata(pdev); 295 296 platform_set_drvdata(pdev, NULL); 297 298 regulator_unregister(ldo->regulator); 299 if (gpio_is_valid(ldo->enable)) 300 gpio_free(ldo->enable); 301 kfree(ldo); 302 303 return 0; 304 } 305 306 static struct platform_driver wm8994_ldo_driver = { 307 .probe = wm8994_ldo_probe, 308 .remove = __devexit_p(wm8994_ldo_remove), 309 .driver = { 310 .name = "wm8994-ldo", 311 .owner = THIS_MODULE, 312 }, 313 }; 314 315 static int __init wm8994_ldo_init(void) 316 { 317 int ret; 318 319 ret = platform_driver_register(&wm8994_ldo_driver); 320 if (ret != 0) 321 pr_err("Failed to register Wm8994 GP LDO driver: %d\n", ret); 322 323 return ret; 324 } 325 subsys_initcall(wm8994_ldo_init); 326 327 static void __exit wm8994_ldo_exit(void) 328 { 329 platform_driver_unregister(&wm8994_ldo_driver); 330 } 331 module_exit(wm8994_ldo_exit); 332 333 /* Module information */ 334 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 335 MODULE_DESCRIPTION("WM8994 LDO driver"); 336 MODULE_LICENSE("GPL"); 337 MODULE_ALIAS("platform:wm8994-ldo"); 338