1 /* 2 * Regulator driver for STw4810/STw4811 VMMC regulator. 3 * 4 * Copyright (C) 2013 ST-Ericsson SA 5 * Written on behalf of Linaro for ST-Ericsson 6 * 7 * Author: Linus Walleij <linus.walleij@linaro.org> 8 * 9 * License terms: GNU General Public License (GPL) version 2 10 */ 11 12 #include <linux/err.h> 13 #include <linux/init.h> 14 #include <linux/mfd/stw481x.h> 15 #include <linux/module.h> 16 #include <linux/platform_device.h> 17 #include <linux/regulator/driver.h> 18 #include <linux/regulator/of_regulator.h> 19 20 static const unsigned int stw481x_vmmc_voltages[] = { 21 1800000, 22 1800000, 23 2850000, 24 3000000, 25 1850000, 26 2600000, 27 2700000, 28 3300000, 29 }; 30 31 static struct regulator_ops stw481x_vmmc_ops = { 32 .list_voltage = regulator_list_voltage_table, 33 .enable = regulator_enable_regmap, 34 .disable = regulator_disable_regmap, 35 .is_enabled = regulator_is_enabled_regmap, 36 .get_voltage_sel = regulator_get_voltage_sel_regmap, 37 .set_voltage_sel = regulator_set_voltage_sel_regmap, 38 }; 39 40 static struct regulator_desc vmmc_regulator = { 41 .name = "VMMC", 42 .id = 0, 43 .ops = &stw481x_vmmc_ops, 44 .type = REGULATOR_VOLTAGE, 45 .owner = THIS_MODULE, 46 .n_voltages = ARRAY_SIZE(stw481x_vmmc_voltages), 47 .volt_table = stw481x_vmmc_voltages, 48 .enable_time = 200, /* FIXME: look this up */ 49 .enable_reg = STW_CONF1, 50 .enable_mask = STW_CONF1_PDN_VMMC | STW_CONF1_MMC_LS_STATUS, 51 .enable_val = STW_CONF1_PDN_VMMC, 52 .vsel_reg = STW_CONF1, 53 .vsel_mask = STW_CONF1_VMMC_MASK, 54 }; 55 56 static int stw481x_vmmc_regulator_probe(struct platform_device *pdev) 57 { 58 struct stw481x *stw481x = dev_get_platdata(&pdev->dev); 59 struct regulator_config config = { }; 60 struct regulator_dev *rdev; 61 int ret; 62 63 /* First disable the external VMMC if it's active */ 64 ret = regmap_update_bits(stw481x->map, STW_CONF2, 65 STW_CONF2_VMMC_EXT, 0); 66 if (ret) { 67 dev_err(&pdev->dev, "could not disable external VMMC\n"); 68 return ret; 69 } 70 71 /* Register VMMC regulator */ 72 config.dev = &pdev->dev; 73 config.driver_data = stw481x; 74 config.regmap = stw481x->map; 75 config.of_node = pdev->dev.of_node; 76 config.init_data = of_get_regulator_init_data(&pdev->dev, 77 pdev->dev.of_node, 78 &vmmc_regulator); 79 80 rdev = devm_regulator_register(&pdev->dev, &vmmc_regulator, &config); 81 if (IS_ERR(rdev)) { 82 dev_err(&pdev->dev, 83 "error initializing STw481x VMMC regulator\n"); 84 return PTR_ERR(rdev); 85 } 86 87 dev_info(&pdev->dev, "initialized STw481x VMMC regulator\n"); 88 return 0; 89 } 90 91 static const struct of_device_id stw481x_vmmc_match[] = { 92 { .compatible = "st,stw481x-vmmc", }, 93 {}, 94 }; 95 96 static struct platform_driver stw481x_vmmc_regulator_driver = { 97 .driver = { 98 .name = "stw481x-vmmc-regulator", 99 .of_match_table = stw481x_vmmc_match, 100 }, 101 .probe = stw481x_vmmc_regulator_probe, 102 }; 103 104 module_platform_driver(stw481x_vmmc_regulator_driver); 105