/* * drivers/regulator/ab3100.c * * Copyright (C) 2008-2009 ST-Ericsson AB * License terms: GNU General Public License (GPL) version 2 * Low-level control of the AB3100 IC Low Dropout (LDO) * regulators, external regulator and buck converter * Author: Mattias Wallin <mattias.wallin@stericsson.com> * Author: Linus Walleij <linus.walleij@stericsson.com> */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/init.h> #include <linux/err.h> #include <linux/delay.h> #include <linux/platform_device.h> #include <linux/regulator/driver.h> #include <linux/mfd/abx500.h> /* LDO registers and some handy masking definitions for AB3100 */ #define AB3100_LDO_A 0x40 #define AB3100_LDO_C 0x41 #define AB3100_LDO_D 0x42 #define AB3100_LDO_E 0x43 #define AB3100_LDO_E_SLEEP 0x44 #define AB3100_LDO_F 0x45 #define AB3100_LDO_G 0x46 #define AB3100_LDO_H 0x47 #define AB3100_LDO_H_SLEEP_MODE 0 #define AB3100_LDO_H_SLEEP_EN 2 #define AB3100_LDO_ON 4 #define AB3100_LDO_H_VSEL_AC 5 #define AB3100_LDO_K 0x48 #define AB3100_LDO_EXT 0x49 #define AB3100_BUCK 0x4A #define AB3100_BUCK_SLEEP 0x4B #define AB3100_REG_ON_MASK 0x10 /** * struct ab3100_regulator * A struct passed around the individual regulator functions * @platform_device: platform device holding this regulator * @dev: handle to the device * @plfdata: AB3100 platform data passed in at probe time * @regreg: regulator register number in the AB3100 * @fixed_voltage: a fixed voltage for this regulator, if this * 0 the voltages array is used instead. * @typ_voltages: an array of available typical voltages for * this regulator * @voltages_len: length of the array of available voltages */ struct ab3100_regulator { struct regulator_dev *rdev; struct device *dev; struct ab3100_platform_data *plfdata; u8 regreg; int fixed_voltage; int const *typ_voltages; u8 voltages_len; }; /* The order in which registers are initialized */ static const u8 ab3100_reg_init_order[AB3100_NUM_REGULATORS+2] = { AB3100_LDO_A, AB3100_LDO_C, AB3100_LDO_E, AB3100_LDO_E_SLEEP, AB3100_LDO_F, AB3100_LDO_G, AB3100_LDO_H, AB3100_LDO_K, AB3100_LDO_EXT, AB3100_BUCK, AB3100_BUCK_SLEEP, AB3100_LDO_D, }; /* Preset (hardware defined) voltages for these regulators */ #define LDO_A_VOLTAGE 2750000 #define LDO_C_VOLTAGE 2650000 #define LDO_D_VOLTAGE 2650000 static const int ldo_e_buck_typ_voltages[] = { 1800000, 1400000, 1300000, 1200000, 1100000, 1050000, 900000, }; static const int ldo_f_typ_voltages[] = { 1800000, 1400000, 1300000, 1200000, 1100000, 1050000, 2500000, 2650000, }; static const int ldo_g_typ_voltages[] = { 2850000, 2750000, 1800000, 1500000, }; static const int ldo_h_typ_voltages[] = { 2750000, 1800000, 1500000, 1200000, }; static const int ldo_k_typ_voltages[] = { 2750000, 1800000, }; /* The regulator devices */ static struct ab3100_regulator ab3100_regulators[AB3100_NUM_REGULATORS] = { { .regreg = AB3100_LDO_A, .fixed_voltage = LDO_A_VOLTAGE, }, { .regreg = AB3100_LDO_C, .fixed_voltage = LDO_C_VOLTAGE, }, { .regreg = AB3100_LDO_D, .fixed_voltage = LDO_D_VOLTAGE, }, { .regreg = AB3100_LDO_E, .typ_voltages = ldo_e_buck_typ_voltages, .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages), }, { .regreg = AB3100_LDO_F, .typ_voltages = ldo_f_typ_voltages, .voltages_len = ARRAY_SIZE(ldo_f_typ_voltages), }, { .regreg = AB3100_LDO_G, .typ_voltages = ldo_g_typ_voltages, .voltages_len = ARRAY_SIZE(ldo_g_typ_voltages), }, { .regreg = AB3100_LDO_H, .typ_voltages = ldo_h_typ_voltages, .voltages_len = ARRAY_SIZE(ldo_h_typ_voltages), }, { .regreg = AB3100_LDO_K, .typ_voltages = ldo_k_typ_voltages, .voltages_len = ARRAY_SIZE(ldo_k_typ_voltages), }, { .regreg = AB3100_LDO_EXT, /* No voltages for the external regulator */ }, { .regreg = AB3100_BUCK, .typ_voltages = ldo_e_buck_typ_voltages, .voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages), }, }; /* * General functions for enable, disable and is_enabled used for * LDO: A,C,E,F,G,H,K,EXT and BUCK */ static int ab3100_enable_regulator(struct regulator_dev *reg) { struct ab3100_regulator *abreg = reg->reg_data; int err; u8 regval; err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg, ®val); if (err) { dev_warn(®->dev, "failed to get regid %d value\n", abreg->regreg); return err; } /* The regulator is already on, no reason to go further */ if (regval & AB3100_REG_ON_MASK) return 0; regval |= AB3100_REG_ON_MASK; err = abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg, regval); if (err) { dev_warn(®->dev, "failed to set regid %d value\n", abreg->regreg); return err; } return 0; } static int ab3100_disable_regulator(struct regulator_dev *reg) { struct ab3100_regulator *abreg = reg->reg_data; int err; u8 regval; /* * LDO D is a special regulator. When it is disabled, the entire * system is shut down. So this is handled specially. */ pr_info("Called ab3100_disable_regulator\n"); if (abreg->regreg == AB3100_LDO_D) { dev_info(®->dev, "disabling LDO D - shut down system\n"); /* Setting LDO D to 0x00 cuts the power to the SoC */ return abx500_set_register_interruptible(abreg->dev, 0, AB3100_LDO_D, 0x00U); } /* * All other regulators are handled here */ err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg, ®val); if (err) { dev_err(®->dev, "unable to get register 0x%x\n", abreg->regreg); return err; } regval &= ~AB3100_REG_ON_MASK; return abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg, regval); } static int ab3100_is_enabled_regulator(struct regulator_dev *reg) { struct ab3100_regulator *abreg = reg->reg_data; u8 regval; int err; err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg, ®val); if (err) { dev_err(®->dev, "unable to get register 0x%x\n", abreg->regreg); return err; } return regval & AB3100_REG_ON_MASK; } static int ab3100_list_voltage_regulator(struct regulator_dev *reg, unsigned selector) { struct ab3100_regulator *abreg = reg->reg_data; if (selector >= abreg->voltages_len) return -EINVAL; return abreg->typ_voltages[selector]; } static int ab3100_get_voltage_regulator(struct regulator_dev *reg) { struct ab3100_regulator *abreg = reg->reg_data; u8 regval; int err; /* Return the voltage for fixed regulators immediately */ if (abreg->fixed_voltage) return abreg->fixed_voltage; /* * For variable types, read out setting and index into * supplied voltage list. */ err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg, ®val); if (err) { dev_warn(®->dev, "failed to get regulator value in register %02x\n", abreg->regreg); return err; } /* The 3 highest bits index voltages */ regval &= 0xE0; regval >>= 5; if (regval >= abreg->voltages_len) { dev_err(®->dev, "regulator register %02x contains an illegal voltage setting\n", abreg->regreg); return -EINVAL; } return abreg->typ_voltages[regval]; } static int ab3100_get_best_voltage_index(struct regulator_dev *reg, int min_uV, int max_uV) { struct ab3100_regulator *abreg = reg->reg_data; int i; int bestmatch; int bestindex; /* * Locate the minimum voltage fitting the criteria on * this regulator. The switchable voltages are not * in strict falling order so we need to check them * all for the best match. */ bestmatch = INT_MAX; bestindex = -1; for (i = 0; i < abreg->voltages_len; i++) { if (abreg->typ_voltages[i] <= max_uV && abreg->typ_voltages[i] >= min_uV && abreg->typ_voltages[i] < bestmatch) { bestmatch = abreg->typ_voltages[i]; bestindex = i; } } if (bestindex < 0) { dev_warn(®->dev, "requested %d<=x<=%d uV, out of range!\n", min_uV, max_uV); return -EINVAL; } return bestindex; } static int ab3100_set_voltage_regulator(struct regulator_dev *reg, int min_uV, int max_uV, unsigned *selector) { struct ab3100_regulator *abreg = reg->reg_data; u8 regval; int err; int bestindex; bestindex = ab3100_get_best_voltage_index(reg, min_uV, max_uV); if (bestindex < 0) return bestindex; *selector = bestindex; err = abx500_get_register_interruptible(abreg->dev, 0, abreg->regreg, ®val); if (err) { dev_warn(®->dev, "failed to get regulator register %02x\n", abreg->regreg); return err; } /* The highest three bits control the variable regulators */ regval &= ~0xE0; regval |= (bestindex << 5); err = abx500_set_register_interruptible(abreg->dev, 0, abreg->regreg, regval); if (err) dev_warn(®->dev, "failed to set regulator register %02x\n", abreg->regreg); return err; } static int ab3100_set_suspend_voltage_regulator(struct regulator_dev *reg, int uV) { struct ab3100_regulator *abreg = reg->reg_data; u8 regval; int err; int bestindex; u8 targetreg; if (abreg->regreg == AB3100_LDO_E) targetreg = AB3100_LDO_E_SLEEP; else if (abreg->regreg == AB3100_BUCK) targetreg = AB3100_BUCK_SLEEP; else return -EINVAL; /* LDO E and BUCK have special suspend voltages you can set */ bestindex = ab3100_get_best_voltage_index(reg, uV, uV); err = abx500_get_register_interruptible(abreg->dev, 0, targetreg, ®val); if (err) { dev_warn(®->dev, "failed to get regulator register %02x\n", targetreg); return err; } /* The highest three bits control the variable regulators */ regval &= ~0xE0; regval |= (bestindex << 5); err = abx500_set_register_interruptible(abreg->dev, 0, targetreg, regval); if (err) dev_warn(®->dev, "failed to set regulator register %02x\n", abreg->regreg); return err; } /* * The external regulator can just define a fixed voltage. */ static int ab3100_get_voltage_regulator_external(struct regulator_dev *reg) { struct ab3100_regulator *abreg = reg->reg_data; return abreg->plfdata->external_voltage; } static int ab3100_enable_time_regulator(struct regulator_dev *reg) { struct ab3100_regulator *abreg = reg->reg_data; /* Per-regulator power on delay from spec */ switch (abreg->regreg) { case AB3100_LDO_A: /* Fallthrough */ case AB3100_LDO_C: /* Fallthrough */ case AB3100_LDO_D: /* Fallthrough */ case AB3100_LDO_E: /* Fallthrough */ case AB3100_LDO_H: /* Fallthrough */ case AB3100_LDO_K: return 200; case AB3100_LDO_F: return 600; case AB3100_LDO_G: return 400; case AB3100_BUCK: return 1000; default: break; } return 0; } static struct regulator_ops regulator_ops_fixed = { .enable = ab3100_enable_regulator, .disable = ab3100_disable_regulator, .is_enabled = ab3100_is_enabled_regulator, .get_voltage = ab3100_get_voltage_regulator, .enable_time = ab3100_enable_time_regulator, }; static struct regulator_ops regulator_ops_variable = { .enable = ab3100_enable_regulator, .disable = ab3100_disable_regulator, .is_enabled = ab3100_is_enabled_regulator, .get_voltage = ab3100_get_voltage_regulator, .set_voltage = ab3100_set_voltage_regulator, .list_voltage = ab3100_list_voltage_regulator, .enable_time = ab3100_enable_time_regulator, }; static struct regulator_ops regulator_ops_variable_sleepable = { .enable = ab3100_enable_regulator, .disable = ab3100_disable_regulator, .is_enabled = ab3100_is_enabled_regulator, .get_voltage = ab3100_get_voltage_regulator, .set_voltage = ab3100_set_voltage_regulator, .set_suspend_voltage = ab3100_set_suspend_voltage_regulator, .list_voltage = ab3100_list_voltage_regulator, .enable_time = ab3100_enable_time_regulator, }; /* * LDO EXT is an external regulator so it is really * not possible to set any voltage locally here, AB3100 * is an on/off switch plain an simple. The external * voltage is defined in the board set-up if any. */ static struct regulator_ops regulator_ops_external = { .enable = ab3100_enable_regulator, .disable = ab3100_disable_regulator, .is_enabled = ab3100_is_enabled_regulator, .get_voltage = ab3100_get_voltage_regulator_external, }; static struct regulator_desc ab3100_regulator_desc[AB3100_NUM_REGULATORS] = { { .name = "LDO_A", .id = AB3100_LDO_A, .ops = ®ulator_ops_fixed, .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, { .name = "LDO_C", .id = AB3100_LDO_C, .ops = ®ulator_ops_fixed, .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, { .name = "LDO_D", .id = AB3100_LDO_D, .ops = ®ulator_ops_fixed, .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, { .name = "LDO_E", .id = AB3100_LDO_E, .ops = ®ulator_ops_variable_sleepable, .n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages), .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, { .name = "LDO_F", .id = AB3100_LDO_F, .ops = ®ulator_ops_variable, .n_voltages = ARRAY_SIZE(ldo_f_typ_voltages), .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, { .name = "LDO_G", .id = AB3100_LDO_G, .ops = ®ulator_ops_variable, .n_voltages = ARRAY_SIZE(ldo_g_typ_voltages), .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, { .name = "LDO_H", .id = AB3100_LDO_H, .ops = ®ulator_ops_variable, .n_voltages = ARRAY_SIZE(ldo_h_typ_voltages), .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, { .name = "LDO_K", .id = AB3100_LDO_K, .ops = ®ulator_ops_variable, .n_voltages = ARRAY_SIZE(ldo_k_typ_voltages), .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, { .name = "LDO_EXT", .id = AB3100_LDO_EXT, .ops = ®ulator_ops_external, .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, { .name = "BUCK", .id = AB3100_BUCK, .ops = ®ulator_ops_variable_sleepable, .n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages), .type = REGULATOR_VOLTAGE, .owner = THIS_MODULE, }, }; /* * NOTE: the following functions are regulators pluralis - it is the * binding to the AB3100 core driver and the parent platform device * for all the different regulators. */ static int __devinit ab3100_regulators_probe(struct platform_device *pdev) { struct ab3100_platform_data *plfdata = pdev->dev.platform_data; int err = 0; u8 data; int i; /* Check chip state */ err = abx500_get_register_interruptible(&pdev->dev, 0, AB3100_LDO_D, &data); if (err) { dev_err(&pdev->dev, "could not read initial status of LDO_D\n"); return err; } if (data & 0x10) dev_notice(&pdev->dev, "chip is already in active mode (Warm start)\n"); else dev_notice(&pdev->dev, "chip is in inactive mode (Cold start)\n"); /* Set up regulators */ for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) { err = abx500_set_register_interruptible(&pdev->dev, 0, ab3100_reg_init_order[i], plfdata->reg_initvals[i]); if (err) { dev_err(&pdev->dev, "regulator initialization failed with error %d\n", err); return err; } } /* Register the regulators */ for (i = 0; i < AB3100_NUM_REGULATORS; i++) { struct ab3100_regulator *reg = &ab3100_regulators[i]; struct regulator_dev *rdev; /* * Initialize per-regulator struct. * Inherit platform data, this comes down from the * i2c boarddata, from the machine. So if you want to * see what it looks like for a certain machine, go * into the machine I2C setup. */ reg->dev = &pdev->dev; reg->plfdata = plfdata; /* * Register the regulator, pass around * the ab3100_regulator struct */ rdev = regulator_register(&ab3100_regulator_desc[i], &pdev->dev, &plfdata->reg_constraints[i], reg, NULL); if (IS_ERR(rdev)) { err = PTR_ERR(rdev); dev_err(&pdev->dev, "%s: failed to register regulator %s err %d\n", __func__, ab3100_regulator_desc[i].name, err); /* remove the already registered regulators */ while (--i >= 0) regulator_unregister(ab3100_regulators[i].rdev); return err; } /* Then set a pointer back to the registered regulator */ reg->rdev = rdev; } return 0; } static int __devexit ab3100_regulators_remove(struct platform_device *pdev) { int i; for (i = 0; i < AB3100_NUM_REGULATORS; i++) { struct ab3100_regulator *reg = &ab3100_regulators[i]; regulator_unregister(reg->rdev); } return 0; } static struct platform_driver ab3100_regulators_driver = { .driver = { .name = "ab3100-regulators", .owner = THIS_MODULE, }, .probe = ab3100_regulators_probe, .remove = __devexit_p(ab3100_regulators_remove), }; static __init int ab3100_regulators_init(void) { return platform_driver_register(&ab3100_regulators_driver); } static __exit void ab3100_regulators_exit(void) { platform_driver_unregister(&ab3100_regulators_driver); } subsys_initcall(ab3100_regulators_init); module_exit(ab3100_regulators_exit); MODULE_AUTHOR("Mattias Wallin <mattias.wallin@stericsson.com>"); MODULE_DESCRIPTION("AB3100 Regulator driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:ab3100-regulators");