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(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 val = (val & WM8994_LDO1_VSEL_MASK) >> WM8994_LDO1_VSEL_SHIFT; 99 100 return wm8994_ldo1_list_voltage(rdev, val); 101 } 102 103 static int wm8994_ldo1_set_voltage(struct regulator_dev *rdev, 104 int min_uV, int max_uV) 105 { 106 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 107 int selector, v; 108 109 selector = (min_uV - 2400000) / 100000; 110 v = wm8994_ldo1_list_voltage(rdev, selector); 111 if (v < 0 || v > max_uV) 112 return -EINVAL; 113 114 selector <<= WM8994_LDO1_VSEL_SHIFT; 115 116 return wm8994_set_bits(ldo->wm8994, WM8994_LDO_1, 117 WM8994_LDO1_VSEL_MASK, selector); 118 } 119 120 static struct regulator_ops wm8994_ldo1_ops = { 121 .enable = wm8994_ldo_enable, 122 .disable = wm8994_ldo_disable, 123 .is_enabled = wm8994_ldo_is_enabled, 124 .enable_time = wm8994_ldo_enable_time, 125 126 .list_voltage = wm8994_ldo1_list_voltage, 127 .get_voltage = wm8994_ldo1_get_voltage, 128 .set_voltage = wm8994_ldo1_set_voltage, 129 }; 130 131 static int wm8994_ldo2_list_voltage(struct regulator_dev *rdev, 132 unsigned int selector) 133 { 134 if (selector > WM8994_LDO2_MAX_SELECTOR) 135 return -EINVAL; 136 137 return (selector * 100000) + 900000; 138 } 139 140 static int wm8994_ldo2_get_voltage(struct regulator_dev *rdev) 141 { 142 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 143 int val; 144 145 val = wm8994_reg_read(ldo->wm8994, WM8994_LDO_2); 146 if (val < 0) 147 return val; 148 149 val = (val & WM8994_LDO2_VSEL_MASK) >> WM8994_LDO2_VSEL_SHIFT; 150 151 return wm8994_ldo2_list_voltage(rdev, val); 152 } 153 154 static int wm8994_ldo2_set_voltage(struct regulator_dev *rdev, 155 int min_uV, int max_uV) 156 { 157 struct wm8994_ldo *ldo = rdev_get_drvdata(rdev); 158 int selector, v; 159 160 selector = (min_uV - 900000) / 100000; 161 v = wm8994_ldo2_list_voltage(rdev, selector); 162 if (v < 0 || v > max_uV) 163 return -EINVAL; 164 165 selector <<= WM8994_LDO2_VSEL_SHIFT; 166 167 return wm8994_set_bits(ldo->wm8994, WM8994_LDO_2, 168 WM8994_LDO2_VSEL_MASK, selector); 169 } 170 171 static struct regulator_ops wm8994_ldo2_ops = { 172 .enable = wm8994_ldo_enable, 173 .disable = wm8994_ldo_disable, 174 .is_enabled = wm8994_ldo_is_enabled, 175 .enable_time = wm8994_ldo_enable_time, 176 177 .list_voltage = wm8994_ldo2_list_voltage, 178 .get_voltage = wm8994_ldo2_get_voltage, 179 .set_voltage = wm8994_ldo2_set_voltage, 180 }; 181 182 static struct regulator_desc wm8994_ldo_desc[] = { 183 { 184 .name = "LDO1", 185 .id = 1, 186 .type = REGULATOR_VOLTAGE, 187 .n_voltages = WM8994_LDO1_MAX_SELECTOR + 1, 188 .ops = &wm8994_ldo1_ops, 189 .owner = THIS_MODULE, 190 }, 191 { 192 .name = "LDO2", 193 .id = 2, 194 .type = REGULATOR_VOLTAGE, 195 .n_voltages = WM8994_LDO2_MAX_SELECTOR + 1, 196 .ops = &wm8994_ldo2_ops, 197 .owner = THIS_MODULE, 198 }, 199 }; 200 201 static __devinit int wm8994_ldo_probe(struct platform_device *pdev) 202 { 203 struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent); 204 struct wm8994_pdata *pdata = wm8994->dev->platform_data; 205 int id = pdev->id % ARRAY_SIZE(pdata->ldo); 206 struct wm8994_ldo *ldo; 207 int ret; 208 209 dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1); 210 211 if (!pdata) 212 return -ENODEV; 213 214 ldo = kzalloc(sizeof(struct wm8994_ldo), GFP_KERNEL); 215 if (ldo == NULL) { 216 dev_err(&pdev->dev, "Unable to allocate private data\n"); 217 return -ENOMEM; 218 } 219 220 ldo->wm8994 = wm8994; 221 222 ldo->is_enabled = true; 223 224 if (pdata->ldo[id].enable && gpio_is_valid(pdata->ldo[id].enable)) { 225 ldo->enable = pdata->ldo[id].enable; 226 227 ret = gpio_request(ldo->enable, "WM8994 LDO enable"); 228 if (ret < 0) { 229 dev_err(&pdev->dev, "Failed to get enable GPIO: %d\n", 230 ret); 231 goto err; 232 } 233 234 ret = gpio_direction_output(ldo->enable, ldo->is_enabled); 235 if (ret < 0) { 236 dev_err(&pdev->dev, "Failed to set GPIO up: %d\n", 237 ret); 238 goto err_gpio; 239 } 240 } 241 242 ldo->regulator = regulator_register(&wm8994_ldo_desc[id], &pdev->dev, 243 pdata->ldo[id].init_data, ldo); 244 if (IS_ERR(ldo->regulator)) { 245 ret = PTR_ERR(ldo->regulator); 246 dev_err(wm8994->dev, "Failed to register LDO%d: %d\n", 247 id + 1, ret); 248 goto err_gpio; 249 } 250 251 platform_set_drvdata(pdev, ldo); 252 253 return 0; 254 255 err_gpio: 256 if (gpio_is_valid(ldo->enable)) 257 gpio_free(ldo->enable); 258 err: 259 kfree(ldo); 260 return ret; 261 } 262 263 static __devexit int wm8994_ldo_remove(struct platform_device *pdev) 264 { 265 struct wm8994_ldo *ldo = platform_get_drvdata(pdev); 266 267 platform_set_drvdata(pdev, NULL); 268 269 regulator_unregister(ldo->regulator); 270 if (gpio_is_valid(ldo->enable)) 271 gpio_free(ldo->enable); 272 kfree(ldo); 273 274 return 0; 275 } 276 277 static struct platform_driver wm8994_ldo_driver = { 278 .probe = wm8994_ldo_probe, 279 .remove = __devexit_p(wm8994_ldo_remove), 280 .driver = { 281 .name = "wm8994-ldo", 282 .owner = THIS_MODULE, 283 }, 284 }; 285 286 static int __init wm8994_ldo_init(void) 287 { 288 int ret; 289 290 ret = platform_driver_register(&wm8994_ldo_driver); 291 if (ret != 0) 292 pr_err("Failed to register Wm8994 GP LDO driver: %d\n", ret); 293 294 return ret; 295 } 296 subsys_initcall(wm8994_ldo_init); 297 298 static void __exit wm8994_ldo_exit(void) 299 { 300 platform_driver_unregister(&wm8994_ldo_driver); 301 } 302 module_exit(wm8994_ldo_exit); 303 304 /* Module information */ 305 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 306 MODULE_DESCRIPTION("WM8994 LDO driver"); 307 MODULE_LICENSE("GPL"); 308 MODULE_ALIAS("platform:wm8994-ldo"); 309