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(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(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 default: 144 return -EINVAL; 145 } 146 } 147 148 static int wm8994_ldo2_get_voltage_sel(struct regulator_dev *rdev) 149 { 150 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 151 int val; 152 153 val = wm8994_reg_read(ldo->wm8994, WM8994_LDO_2); 154 if (val < 0) 155 return val; 156 157 return (val & WM8994_LDO2_VSEL_MASK) >> WM8994_LDO2_VSEL_SHIFT; 158 } 159 160 static int wm8994_ldo2_set_voltage(struct regulator_dev *rdev, 161 int min_uV, int max_uV, unsigned *s) 162 { 163 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 164 int selector, v; 165 166 switch (ldo->wm8994->type) { 167 case WM8994: 168 selector = (min_uV - 900000) / 100000; 169 break; 170 case WM8958: 171 selector = (min_uV - 1000000) / 100000; 172 break; 173 default: 174 return -EINVAL; 175 } 176 177 v = wm8994_ldo2_list_voltage(rdev, selector); 178 if (v < 0 || v > max_uV) 179 return -EINVAL; 180 181 *s = selector; 182 selector <<= WM8994_LDO2_VSEL_SHIFT; 183 184 return wm8994_set_bits(ldo->wm8994, WM8994_LDO_2, 185 WM8994_LDO2_VSEL_MASK, selector); 186 } 187 188 static struct regulator_ops wm8994_ldo2_ops = { 189 .enable = wm8994_ldo_enable, 190 .disable = wm8994_ldo_disable, 191 .is_enabled = wm8994_ldo_is_enabled, 192 .enable_time = wm8994_ldo_enable_time, 193 194 .list_voltage = wm8994_ldo2_list_voltage, 195 .get_voltage_sel = wm8994_ldo2_get_voltage_sel, 196 .set_voltage = wm8994_ldo2_set_voltage, 197 }; 198 199 static struct regulator_desc wm8994_ldo_desc[] = { 200 { 201 .name = "LDO1", 202 .id = 1, 203 .type = REGULATOR_VOLTAGE, 204 .n_voltages = WM8994_LDO1_MAX_SELECTOR + 1, 205 .ops = &wm8994_ldo1_ops, 206 .owner = THIS_MODULE, 207 }, 208 { 209 .name = "LDO2", 210 .id = 2, 211 .type = REGULATOR_VOLTAGE, 212 .n_voltages = WM8994_LDO2_MAX_SELECTOR + 1, 213 .ops = &wm8994_ldo2_ops, 214 .owner = THIS_MODULE, 215 }, 216 }; 217 218 static __devinit int wm8994_ldo_probe(struct platform_device *pdev) 219 { 220 struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent); 221 struct wm8994_pdata *pdata = wm8994->dev->platform_data; 222 int id = pdev->id % ARRAY_SIZE(pdata->ldo); 223 struct wm8994_ldo *ldo; 224 int ret; 225 226 dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1); 227 228 if (!pdata) 229 return -ENODEV; 230 231 ldo = kzalloc(sizeof(struct wm8994_ldo), GFP_KERNEL); 232 if (ldo == NULL) { 233 dev_err(&pdev->dev, "Unable to allocate private data\n"); 234 return -ENOMEM; 235 } 236 237 ldo->wm8994 = wm8994; 238 239 if (pdata->ldo[id].enable && gpio_is_valid(pdata->ldo[id].enable)) { 240 ldo->enable = pdata->ldo[id].enable; 241 242 ret = gpio_request(ldo->enable, "WM8994 LDO enable"); 243 if (ret < 0) { 244 dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", 245 ret); 246 goto err; 247 } 248 249 ret = gpio_direction_output(ldo->enable, ldo->is_enabled); 250 if (ret < 0) { 251 dev_err(&pdev->dev, "Failed to set GPIO up: %d\n", 252 ret); 253 goto err_gpio; 254 } 255 } else 256 ldo->is_enabled = true; 257 258 ldo->regulator = regulator_register(&wm8994_ldo_desc[id], &pdev->dev, 259 pdata->ldo[id].init_data, ldo); 260 if (IS_ERR(ldo->regulator)) { 261 ret = PTR_ERR(ldo->regulator); 262 dev_err(wm8994->dev, "Failed to register LDO%d: %d\n", 263 id + 1, ret); 264 goto err_gpio; 265 } 266 267 platform_set_drvdata(pdev, ldo); 268 269 return 0; 270 271 err_gpio: 272 if (gpio_is_valid(ldo->enable)) 273 gpio_free(ldo->enable); 274 err: 275 kfree(ldo); 276 return ret; 277 } 278 279 static __devexit int wm8994_ldo_remove(struct platform_device *pdev) 280 { 281 struct wm8994_ldo *ldo = platform_get_drvdata(pdev); 282 283 platform_set_drvdata(pdev, NULL); 284 285 regulator_unregister(ldo->regulator); 286 if (gpio_is_valid(ldo->enable)) 287 gpio_free(ldo->enable); 288 kfree(ldo); 289 290 return 0; 291 } 292 293 static struct platform_driver wm8994_ldo_driver = { 294 .probe = wm8994_ldo_probe, 295 .remove = __devexit_p(wm8994_ldo_remove), 296 .driver = { 297 .name = "wm8994-ldo", 298 .owner = THIS_MODULE, 299 }, 300 }; 301 302 static int __init wm8994_ldo_init(void) 303 { 304 int ret; 305 306 ret = platform_driver_register(&wm8994_ldo_driver); 307 if (ret != 0) 308 pr_err("Failed to register Wm8994 GP LDO driver: %d\n", ret); 309 310 return ret; 311 } 312 subsys_initcall(wm8994_ldo_init); 313 314 static void __exit wm8994_ldo_exit(void) 315 { 316 platform_driver_unregister(&wm8994_ldo_driver); 317 } 318 module_exit(wm8994_ldo_exit); 319 320 /* Module information */ 321 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 322 MODULE_DESCRIPTION("WM8994 LDO driver"); 323 MODULE_LICENSE("GPL"); 324 MODULE_ALIAS("platform:wm8994-ldo"); 325