diff options
Diffstat (limited to 'drivers/regulator/ltc3589.c')
-rw-r--r-- | drivers/regulator/ltc3589.c | 554 |
1 files changed, 554 insertions, 0 deletions
diff --git a/drivers/regulator/ltc3589.c b/drivers/regulator/ltc3589.c new file mode 100644 index 000000000000..110a99ee1162 --- /dev/null +++ b/drivers/regulator/ltc3589.c @@ -0,0 +1,554 @@ +/* + * Linear Technology LTC3589,LTC3589-1 regulator support + * + * Copyright (c) 2014 Philipp Zabel <p.zabel@pengutronix.de>, Pengutronix + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/regmap.h> +#include <linux/regulator/driver.h> +#include <linux/regulator/of_regulator.h> + +#define DRIVER_NAME "ltc3589" + +#define LTC3589_IRQSTAT 0x02 +#define LTC3589_SCR1 0x07 +#define LTC3589_OVEN 0x10 +#define LTC3589_SCR2 0x12 +#define LTC3589_PGSTAT 0x13 +#define LTC3589_VCCR 0x20 +#define LTC3589_CLIRQ 0x21 +#define LTC3589_B1DTV1 0x23 +#define LTC3589_B1DTV2 0x24 +#define LTC3589_VRRCR 0x25 +#define LTC3589_B2DTV1 0x26 +#define LTC3589_B2DTV2 0x27 +#define LTC3589_B3DTV1 0x29 +#define LTC3589_B3DTV2 0x2a +#define LTC3589_L2DTV1 0x32 +#define LTC3589_L2DTV2 0x33 + +#define LTC3589_IRQSTAT_PGOOD_TIMEOUT BIT(3) +#define LTC3589_IRQSTAT_UNDERVOLT_WARN BIT(4) +#define LTC3589_IRQSTAT_UNDERVOLT_FAULT BIT(5) +#define LTC3589_IRQSTAT_THERMAL_WARN BIT(6) +#define LTC3589_IRQSTAT_THERMAL_FAULT BIT(7) + +#define LTC3589_OVEN_SW1 BIT(0) +#define LTC3589_OVEN_SW2 BIT(1) +#define LTC3589_OVEN_SW3 BIT(2) +#define LTC3589_OVEN_BB_OUT BIT(3) +#define LTC3589_OVEN_LDO2 BIT(4) +#define LTC3589_OVEN_LDO3 BIT(5) +#define LTC3589_OVEN_LDO4 BIT(6) +#define LTC3589_OVEN_SW_CTRL BIT(7) + +#define LTC3589_VCCR_SW1_GO BIT(0) +#define LTC3589_VCCR_SW2_GO BIT(2) +#define LTC3589_VCCR_SW3_GO BIT(4) +#define LTC3589_VCCR_LDO2_GO BIT(6) + +enum ltc3589_variant { + LTC3589, + LTC3589_1, + LTC3589_2, +}; + +enum ltc3589_reg { + LTC3589_SW1, + LTC3589_SW2, + LTC3589_SW3, + LTC3589_BB_OUT, + LTC3589_LDO1, + LTC3589_LDO2, + LTC3589_LDO3, + LTC3589_LDO4, + LTC3589_NUM_REGULATORS, +}; + +struct ltc3589_regulator { + struct regulator_desc desc; + + /* External feedback voltage divider */ + unsigned int r1; + unsigned int r2; +}; + +struct ltc3589 { + struct regmap *regmap; + struct device *dev; + enum ltc3589_variant variant; + struct ltc3589_regulator regulator_descs[LTC3589_NUM_REGULATORS]; + struct regulator_dev *regulators[LTC3589_NUM_REGULATORS]; +}; + +static const int ltc3589_ldo4[] = { + 2800000, 2500000, 1800000, 3300000, +}; + +static const int ltc3589_12_ldo4[] = { + 1200000, 1800000, 2500000, 3200000, +}; + +static int ltc3589_set_ramp_delay(struct regulator_dev *rdev, int ramp_delay) +{ + struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev); + int sel, shift; + + if (unlikely(ramp_delay <= 0)) + return -EINVAL; + + /* VRRCR slew rate offsets are the same as VCCR go bit offsets */ + shift = ffs(rdev->desc->apply_bit) - 1; + + /* The slew rate can be set to 0.88, 1.75, 3.5, or 7 mV/uS */ + for (sel = 0; sel < 4; sel++) { + if ((880 << sel) >= ramp_delay) { + return regmap_update_bits(ltc3589->regmap, + LTC3589_VRRCR, + 0x3 << shift, sel << shift); + } + } + return -EINVAL; +} + +static int ltc3589_set_suspend_voltage(struct regulator_dev *rdev, int uV) +{ + struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev); + int sel; + + sel = regulator_map_voltage_linear(rdev, uV, uV); + if (sel < 0) + return sel; + + /* DTV2 register follows right after the corresponding DTV1 register */ + return regmap_update_bits(ltc3589->regmap, rdev->desc->vsel_reg + 1, + rdev->desc->vsel_mask, sel); +} + +static int ltc3589_set_suspend_mode(struct regulator_dev *rdev, + unsigned int mode) +{ + struct ltc3589 *ltc3589 = rdev_get_drvdata(rdev); + int mask, bit = 0; + + /* VCCR reference selects are right next to the VCCR go bits */ + mask = rdev->desc->apply_bit << 1; + + if (mode == REGULATOR_MODE_STANDBY) + bit = mask; /* Select DTV2 */ + + mask |= rdev->desc->apply_bit; + bit |= rdev->desc->apply_bit; + return regmap_update_bits(ltc3589->regmap, LTC3589_VCCR, mask, bit); +} + +/* SW1, SW2, SW3, LDO2 */ +static struct regulator_ops ltc3589_linear_regulator_ops = { + .enable = regulator_enable_regmap, + .disable = regulator_disable_regmap, + .is_enabled = regulator_is_enabled_regmap, + .list_voltage = regulator_list_voltage_linear, + .set_voltage_sel = regulator_set_voltage_sel_regmap, + .get_voltage_sel = regulator_get_voltage_sel_regmap, + .set_ramp_delay = ltc3589_set_ramp_delay, + .set_voltage_time_sel = regulator_set_voltage_time_sel, + .set_suspend_voltage = ltc3589_set_suspend_voltage, + .set_suspend_mode = ltc3589_set_suspend_mode, +}; + +/* BB_OUT, LDO3 */ +static struct regulator_ops ltc3589_fixed_regulator_ops = { + .enable = regulator_enable_regmap, + .disable = regulator_disable_regmap, + .is_enabled = regulator_is_enabled_regmap, +}; + +/* LDO1 */ +static struct regulator_ops ltc3589_fixed_standby_regulator_ops = { +}; + +/* LDO4 */ +static struct regulator_ops ltc3589_table_regulator_ops = { + .enable = regulator_enable_regmap, + .disable = regulator_disable_regmap, + .is_enabled = regulator_is_enabled_regmap, + .list_voltage = regulator_list_voltage_table, + .set_voltage_sel = regulator_set_voltage_sel_regmap, + .get_voltage_sel = regulator_get_voltage_sel_regmap, +}; + + +#define LTC3589_REG(_name, _ops, en_bit, dtv1_reg, dtv_mask, go_bit) \ + [LTC3589_ ## _name] = { \ + .desc = { \ + .name = #_name, \ + .n_voltages = (dtv_mask) + 1, \ + .min_uV = (go_bit) ? 362500 : 0, \ + .uV_step = (go_bit) ? 12500 : 0, \ + .ramp_delay = (go_bit) ? 1750 : 0, \ + .fixed_uV = (dtv_mask) ? 0 : 800000, \ + .ops = <c3589_ ## _ops ## _regulator_ops, \ + .type = REGULATOR_VOLTAGE, \ + .id = LTC3589_ ## _name, \ + .owner = THIS_MODULE, \ + .vsel_reg = (dtv1_reg), \ + .vsel_mask = (dtv_mask), \ + .apply_reg = (go_bit) ? LTC3589_VCCR : 0, \ + .apply_bit = (go_bit), \ + .enable_reg = (en_bit) ? LTC3589_OVEN : 0, \ + .enable_mask = (en_bit), \ + }, \ + } + +#define LTC3589_LINEAR_REG(_name, _dtv1) \ + LTC3589_REG(_name, linear, LTC3589_OVEN_ ## _name, \ + LTC3589_ ## _dtv1, 0x1f, \ + LTC3589_VCCR_ ## _name ## _GO) + +#define LTC3589_FIXED_REG(_name) \ + LTC3589_REG(_name, fixed, LTC3589_OVEN_ ## _name, 0, 0, 0) + +static struct ltc3589_regulator ltc3589_regulators[LTC3589_NUM_REGULATORS] = { + LTC3589_LINEAR_REG(SW1, B1DTV1), + LTC3589_LINEAR_REG(SW2, B2DTV1), + LTC3589_LINEAR_REG(SW3, B3DTV1), + LTC3589_FIXED_REG(BB_OUT), + LTC3589_REG(LDO1, fixed_standby, 0, 0, 0, 0), + LTC3589_LINEAR_REG(LDO2, L2DTV1), + LTC3589_FIXED_REG(LDO3), + LTC3589_REG(LDO4, table, LTC3589_OVEN_LDO4, LTC3589_L2DTV2, 0x60, 0), +}; + +#ifdef CONFIG_OF +static struct of_regulator_match ltc3589_matches[LTC3589_NUM_REGULATORS] = { + { .name = "sw1", }, + { .name = "sw2", }, + { .name = "sw3", }, + { .name = "bb-out", }, + { .name = "ldo1", }, /* standby */ + { .name = "ldo2", }, + { .name = "ldo3", }, + { .name = "ldo4", }, +}; + +static int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589) +{ + struct device *dev = ltc3589->dev; + struct device_node *node; + int i, ret; + + node = of_find_node_by_name(dev->of_node, "regulators"); + if (!node) { + dev_err(dev, "regulators node not found\n"); + return -EINVAL; + } + + ret = of_regulator_match(dev, node, ltc3589_matches, + ARRAY_SIZE(ltc3589_matches)); + of_node_put(node); + if (ret < 0) { + dev_err(dev, "Error parsing regulator init data: %d\n", ret); + return ret; + } + if (ret != LTC3589_NUM_REGULATORS) { + dev_err(dev, "Only %d regulators described in device tree\n", + ret); + return -EINVAL; + } + + /* Parse feedback voltage dividers. LDO3 and LDO4 don't have them */ + for (i = 0; i < LTC3589_LDO3; i++) { + struct ltc3589_regulator *desc = <c3589->regulator_descs[i]; + struct device_node *np = ltc3589_matches[i].of_node; + u32 vdiv[2]; + + ret = of_property_read_u32_array(np, "lltc,fb-voltage-divider", + vdiv, 2); + if (ret) { + dev_err(dev, "Failed to parse voltage divider: %d\n", + ret); + return ret; + } + + desc->r1 = vdiv[0]; + desc->r2 = vdiv[1]; + } + + return 0; +} + +static inline struct regulator_init_data *match_init_data(int index) +{ + return ltc3589_matches[index].init_data; +} + +static inline struct device_node *match_of_node(int index) +{ + return ltc3589_matches[index].of_node; +} +#else +static inline int ltc3589_parse_regulators_dt(struct ltc3589 *ltc3589) +{ + return 0; +} + +static inline struct regulator_init_data *match_init_data(int index) +{ + return NULL; +} + +static inline struct device_node *match_of_node(int index) +{ + return NULL; +} +#endif + +static bool ltc3589_writeable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LTC3589_IRQSTAT: + case LTC3589_SCR1: + case LTC3589_OVEN: + case LTC3589_SCR2: + case LTC3589_VCCR: + case LTC3589_CLIRQ: + case LTC3589_B1DTV1: + case LTC3589_B1DTV2: + case LTC3589_VRRCR: + case LTC3589_B2DTV1: + case LTC3589_B2DTV2: + case LTC3589_B3DTV1: + case LTC3589_B3DTV2: + case LTC3589_L2DTV1: + case LTC3589_L2DTV2: + return true; + } + return false; +} + +static bool ltc3589_readable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LTC3589_IRQSTAT: + case LTC3589_SCR1: + case LTC3589_OVEN: + case LTC3589_SCR2: + case LTC3589_PGSTAT: + case LTC3589_VCCR: + case LTC3589_B1DTV1: + case LTC3589_B1DTV2: + case LTC3589_VRRCR: + case LTC3589_B2DTV1: + case LTC3589_B2DTV2: + case LTC3589_B3DTV1: + case LTC3589_B3DTV2: + case LTC3589_L2DTV1: + case LTC3589_L2DTV2: + return true; + } + return false; +} + +static bool ltc3589_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case LTC3589_IRQSTAT: + case LTC3589_PGSTAT: + return true; + } + return false; +} + +struct reg_default ltc3589_reg_defaults[] = { + { LTC3589_SCR1, 0x00 }, + { LTC3589_OVEN, 0x00 }, + { LTC3589_SCR2, 0x00 }, + { LTC3589_VCCR, 0x00 }, + { LTC3589_B1DTV1, 0x19 }, + { LTC3589_B1DTV2, 0x19 }, + { LTC3589_VRRCR, 0xff }, + { LTC3589_B2DTV1, 0x19 }, + { LTC3589_B2DTV2, 0x19 }, + { LTC3589_B3DTV1, 0x19 }, + { LTC3589_B3DTV2, 0x19 }, + { LTC3589_L2DTV1, 0x19 }, + { LTC3589_L2DTV2, 0x19 }, +}; + +static const struct regmap_config ltc3589_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .writeable_reg = ltc3589_writeable_reg, + .readable_reg = ltc3589_readable_reg, + .volatile_reg = ltc3589_volatile_reg, + .max_register = LTC3589_L2DTV2, + .reg_defaults = ltc3589_reg_defaults, + .num_reg_defaults = ARRAY_SIZE(ltc3589_reg_defaults), + .use_single_rw = true, + .cache_type = REGCACHE_RBTREE, +}; + + +static irqreturn_t ltc3589_isr(int irq, void *dev_id) +{ + struct ltc3589 *ltc3589 = dev_id; + unsigned int i, irqstat, event; + + regmap_read(ltc3589->regmap, LTC3589_IRQSTAT, &irqstat); + + if (irqstat & LTC3589_IRQSTAT_THERMAL_WARN) { + event = REGULATOR_EVENT_OVER_TEMP; + for (i = 0; i < LTC3589_NUM_REGULATORS; i++) + regulator_notifier_call_chain(ltc3589->regulators[i], + event, NULL); + } + + if (irqstat & LTC3589_IRQSTAT_UNDERVOLT_WARN) { + event = REGULATOR_EVENT_UNDER_VOLTAGE; + for (i = 0; i < LTC3589_NUM_REGULATORS; i++) + regulator_notifier_call_chain(ltc3589->regulators[i], + event, NULL); + } + + /* Clear warning condition */ + regmap_write(ltc3589->regmap, LTC3589_CLIRQ, 0); + + return IRQ_HANDLED; +} + +static inline unsigned int ltc3589_scale(unsigned int uV, u32 r1, u32 r2) +{ + uint64_t tmp; + if (uV == 0) + return 0; + tmp = (uint64_t)uV * r1; + do_div(tmp, r2); + return uV + (unsigned int)tmp; +} + +static void ltc3589_apply_fb_voltage_divider(struct ltc3589_regulator *rdesc) +{ + struct regulator_desc *desc = &rdesc->desc; + + if (!rdesc->r1 || !rdesc->r2) + return; + + desc->min_uV = ltc3589_scale(desc->min_uV, rdesc->r1, rdesc->r2); + desc->uV_step = ltc3589_scale(desc->uV_step, rdesc->r1, rdesc->r2); + desc->fixed_uV = ltc3589_scale(desc->fixed_uV, rdesc->r1, rdesc->r2); +} + +static int ltc3589_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device *dev = &client->dev; + struct ltc3589_regulator *descs; + struct ltc3589 *ltc3589; + int i, ret; + + ltc3589 = devm_kzalloc(dev, sizeof(*ltc3589), GFP_KERNEL); + if (!ltc3589) + return -ENOMEM; + + i2c_set_clientdata(client, ltc3589); + ltc3589->variant = id->driver_data; + ltc3589->dev = dev; + + descs = ltc3589->regulator_descs; + memcpy(descs, ltc3589_regulators, sizeof(ltc3589_regulators)); + if (ltc3589->variant == LTC3589) { + descs[LTC3589_LDO3].desc.fixed_uV = 1800000; + descs[LTC3589_LDO4].desc.volt_table = ltc3589_ldo4; + } else { + descs[LTC3589_LDO3].desc.fixed_uV = 2800000; + descs[LTC3589_LDO4].desc.volt_table = ltc3589_12_ldo4; + } + + ltc3589->regmap = devm_regmap_init_i2c(client, <c3589_regmap_config); + if (IS_ERR(ltc3589->regmap)) { + ret = PTR_ERR(ltc3589->regmap); + dev_err(dev, "failed to initialize regmap: %d\n", ret); + return ret; + } + + ret = ltc3589_parse_regulators_dt(ltc3589); + if (ret) + return ret; + + for (i = 0; i < LTC3589_NUM_REGULATORS; i++) { + struct ltc3589_regulator *rdesc = <c3589->regulator_descs[i]; + struct regulator_desc *desc = &rdesc->desc; + struct regulator_init_data *init_data; + struct regulator_config config = { }; + + init_data = match_init_data(i); + + if (i < LTC3589_LDO3) + ltc3589_apply_fb_voltage_divider(rdesc); + + config.dev = dev; + config.init_data = init_data; + config.driver_data = ltc3589; + config.of_node = match_of_node(i); + + ltc3589->regulators[i] = devm_regulator_register(dev, desc, + &config); + if (IS_ERR(ltc3589->regulators[i])) { + ret = PTR_ERR(ltc3589->regulators[i]); + dev_err(dev, "failed to register regulator %s: %d\n", + desc->name, ret); + return ret; + } + } + + ret = devm_request_threaded_irq(dev, client->irq, NULL, ltc3589_isr, + IRQF_TRIGGER_LOW | IRQF_ONESHOT, + client->name, ltc3589); + if (ret) { + dev_err(dev, "Failed to request IRQ: %d\n", ret); + return ret; + } + + return 0; +} + +static struct i2c_device_id ltc3589_i2c_id[] = { + { "ltc3589", LTC3589 }, + { "ltc3589-1", LTC3589_1 }, + { "ltc3589-2", LTC3589_2 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ltc3589_i2c_id); + +static struct i2c_driver ltc3589_driver = { + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + }, + .probe = ltc3589_probe, + .id_table = ltc3589_i2c_id, +}; +module_i2c_driver(ltc3589_driver); + +MODULE_AUTHOR("Philipp Zabel <p.zabel@pengutronix.de>"); +MODULE_DESCRIPTION("Regulator driver for Linear Technology LTC3589(-1,2)"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("i2c:ltc3589"); |