1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Regulator driver for STw4810/STw4811 VMMC regulator. 4 * 5 * Copyright (C) 2013 ST-Ericsson SA 6 * Written on behalf of Linaro for ST-Ericsson 7 * 8 * Author: Linus Walleij <linus.walleij@linaro.org> 9 */ 10 11 #include <linux/err.h> 12 #include <linux/init.h> 13 #include <linux/mfd/stw481x.h> 14 #include <linux/module.h> 15 #include <linux/platform_device.h> 16 #include <linux/regulator/driver.h> 17 #include <linux/regulator/of_regulator.h> 18 19 static const unsigned int stw481x_vmmc_voltages[] = { 20 1800000, 21 1800000, 22 2850000, 23 3000000, 24 1850000, 25 2600000, 26 2700000, 27 3300000, 28 }; 29 30 static const struct regulator_ops stw481x_vmmc_ops = { 31 .list_voltage = regulator_list_voltage_table, 32 .enable = regulator_enable_regmap, 33 .disable = regulator_disable_regmap, 34 .is_enabled = regulator_is_enabled_regmap, 35 .get_voltage_sel = regulator_get_voltage_sel_regmap, 36 .set_voltage_sel = regulator_set_voltage_sel_regmap, 37 }; 38 39 static const struct regulator_desc vmmc_regulator = { 40 .name = "VMMC", 41 .id = 0, 42 .ops = &stw481x_vmmc_ops, 43 .type = REGULATOR_VOLTAGE, 44 .owner = THIS_MODULE, 45 .n_voltages = ARRAY_SIZE(stw481x_vmmc_voltages), 46 .volt_table = stw481x_vmmc_voltages, 47 .enable_time = 200, /* FIXME: look this up */ 48 .enable_reg = STW_CONF1, 49 .enable_mask = STW_CONF1_PDN_VMMC | STW_CONF1_MMC_LS_STATUS, 50 .enable_val = STW_CONF1_PDN_VMMC, 51 .vsel_reg = STW_CONF1, 52 .vsel_mask = STW_CONF1_VMMC_MASK, 53 }; 54 55 static int stw481x_vmmc_regulator_probe(struct platform_device *pdev) 56 { 57 struct stw481x *stw481x = dev_get_platdata(&pdev->dev); 58 struct regulator_config config = { }; 59 struct regulator_dev *rdev; 60 int ret; 61 62 /* First disable the external VMMC if it's active */ 63 ret = regmap_update_bits(stw481x->map, STW_CONF2, 64 STW_CONF2_VMMC_EXT, 0); 65 if (ret) { 66 dev_err(&pdev->dev, "could not disable external VMMC\n"); 67 return ret; 68 } 69 70 /* Register VMMC regulator */ 71 config.dev = &pdev->dev; 72 config.driver_data = stw481x; 73 config.regmap = stw481x->map; 74 config.of_node = pdev->dev.of_node; 75 config.init_data = of_get_regulator_init_data(&pdev->dev, 76 pdev->dev.of_node, 77 &vmmc_regulator); 78 79 rdev = devm_regulator_register(&pdev->dev, &vmmc_regulator, &config); 80 if (IS_ERR(rdev)) { 81 dev_err(&pdev->dev, 82 "error initializing STw481x VMMC regulator\n"); 83 return PTR_ERR(rdev); 84 } 85 86 dev_info(&pdev->dev, "initialized STw481x VMMC regulator\n"); 87 return 0; 88 } 89 90 static const struct of_device_id stw481x_vmmc_match[] = { 91 { .compatible = "st,stw481x-vmmc", }, 92 {}, 93 }; 94 95 static struct platform_driver stw481x_vmmc_regulator_driver = { 96 .driver = { 97 .name = "stw481x-vmmc-regulator", 98 .probe_type = PROBE_PREFER_ASYNCHRONOUS, 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