diff options
Diffstat (limited to 'drivers/regulator/rt6245-regulator.c')
| -rw-r--r-- | drivers/regulator/rt6245-regulator.c | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/drivers/regulator/rt6245-regulator.c b/drivers/regulator/rt6245-regulator.c new file mode 100644 index 000000000000..d3299a72fd10 --- /dev/null +++ b/drivers/regulator/rt6245-regulator.c @@ -0,0 +1,254 @@ +// SPDX-License-Identifier: GPL-2.0+ + +#include <linux/bitops.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/regmap.h> +#include <linux/regulator/driver.h> +#include <linux/regulator/of_regulator.h> + +#define RT6245_VIRT_OCLIMIT 0x00 +#define RT6245_VIRT_OTLEVEL 0x01 +#define RT6245_VIRT_PGDLYTIME 0x02 +#define RT6245_VIRT_SLEWRATE 0x03 +#define RT6245_VIRT_SWFREQ 0x04 +#define RT6245_VIRT_VOUT 0x05 + +#define RT6245_VOUT_MASK GENMASK(6, 0) +#define RT6245_SLEW_MASK GENMASK(2, 0) +#define RT6245_CHKSUM_MASK BIT(7) +#define RT6245_CODE_MASK GENMASK(6, 0) + +/* HW Enable + Soft start time */ +#define RT6245_ENTIME_IN_US 5000 + +#define RT6245_VOUT_MINUV 437500 +#define RT6245_VOUT_MAXUV 1387500 +#define RT6245_VOUT_STEPUV 12500 +#define RT6245_NUM_VOUT ((RT6245_VOUT_MAXUV - RT6245_VOUT_MINUV) / RT6245_VOUT_STEPUV + 1) + +struct rt6245_priv { + struct gpio_desc *enable_gpio; + bool enable_state; +}; + +static int rt6245_enable(struct regulator_dev *rdev) +{ + struct rt6245_priv *priv = rdev_get_drvdata(rdev); + struct regmap *regmap = rdev_get_regmap(rdev); + int ret; + + if (!priv->enable_gpio) + return 0; + + gpiod_direction_output(priv->enable_gpio, 1); + usleep_range(RT6245_ENTIME_IN_US, RT6245_ENTIME_IN_US + 1000); + + regcache_cache_only(regmap, false); + ret = regcache_sync(regmap); + if (ret) + return ret; + + priv->enable_state = true; + return 0; +} + +static int rt6245_disable(struct regulator_dev *rdev) +{ + struct rt6245_priv *priv = rdev_get_drvdata(rdev); + struct regmap *regmap = rdev_get_regmap(rdev); + + if (!priv->enable_gpio) + return -EINVAL; + + regcache_cache_only(regmap, true); + regcache_mark_dirty(regmap); + + gpiod_direction_output(priv->enable_gpio, 0); + + priv->enable_state = false; + return 0; +} + +static int rt6245_is_enabled(struct regulator_dev *rdev) +{ + struct rt6245_priv *priv = rdev_get_drvdata(rdev); + + return priv->enable_state ? 1 : 0; +} + +static const struct regulator_ops rt6245_regulator_ops = { + .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 = regulator_set_ramp_delay_regmap, + .enable = rt6245_enable, + .disable = rt6245_disable, + .is_enabled = rt6245_is_enabled, +}; + +/* ramp delay dividend is 12500 uV/uS, and divisor from 1 to 8 */ +static const unsigned int rt6245_ramp_delay_table[] = { + 12500, 6250, 4167, 3125, 2500, 2083, 1786, 1562 +}; + +static const struct regulator_desc rt6245_regulator_desc = { + .name = "rt6245-regulator", + .ops = &rt6245_regulator_ops, + .type = REGULATOR_VOLTAGE, + .min_uV = RT6245_VOUT_MINUV, + .uV_step = RT6245_VOUT_STEPUV, + .n_voltages = RT6245_NUM_VOUT, + .ramp_delay_table = rt6245_ramp_delay_table, + .n_ramp_values = ARRAY_SIZE(rt6245_ramp_delay_table), + .owner = THIS_MODULE, + .vsel_reg = RT6245_VIRT_VOUT, + .vsel_mask = RT6245_VOUT_MASK, + .ramp_reg = RT6245_VIRT_SLEWRATE, + .ramp_mask = RT6245_SLEW_MASK, +}; + +static int rt6245_init_device_properties(struct device *dev) +{ + const struct { + const char *name; + unsigned int reg; + } rt6245_props[] = { + { "richtek,oc-level-select", RT6245_VIRT_OCLIMIT }, + { "richtek,ot-level-select", RT6245_VIRT_OTLEVEL }, + { "richtek,pgdly-time-select", RT6245_VIRT_PGDLYTIME }, + { "richtek,switch-freq-select", RT6245_VIRT_SWFREQ } + }; + struct regmap *regmap = dev_get_regmap(dev, NULL); + u8 propval; + int i, ret; + + for (i = 0; i < ARRAY_SIZE(rt6245_props); i++) { + ret = device_property_read_u8(dev, rt6245_props[i].name, &propval); + if (ret) + continue; + + ret = regmap_write(regmap, rt6245_props[i].reg, propval); + if (ret) { + dev_err(dev, "Fail to apply [%s:%d]\n", rt6245_props[i].name, propval); + return ret; + } + } + + return 0; +} + +static int rt6245_reg_write(void *context, unsigned int reg, unsigned int val) +{ + struct i2c_client *i2c = context; + const u8 func_base[] = { 0x6F, 0x73, 0x78, 0x61, 0x7C, 0 }; + unsigned int code, bit_count; + + code = func_base[reg]; + code += val; + + /* xor checksum for bit 6 to 0 */ + bit_count = hweight8(code & RT6245_CODE_MASK); + if (bit_count % 2) + code |= RT6245_CHKSUM_MASK; + else + code &= ~RT6245_CHKSUM_MASK; + + return i2c_smbus_write_byte(i2c, code); +} + +static const struct reg_default rt6245_reg_defaults[] = { + /* Default over current 14A */ + { RT6245_VIRT_OCLIMIT, 2 }, + /* Default over temperature 150'c */ + { RT6245_VIRT_OTLEVEL, 0 }, + /* Default power good delay time 10us */ + { RT6245_VIRT_PGDLYTIME, 1 }, + /* Default slewrate 12.5mV/uS */ + { RT6245_VIRT_SLEWRATE, 0 }, + /* Default switch frequency 800KHz */ + { RT6245_VIRT_SWFREQ, 1 }, + /* Default voltage 750mV */ + { RT6245_VIRT_VOUT, 0x19 } +}; + +static const struct regmap_config rt6245_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = RT6245_VIRT_VOUT, + .cache_type = REGCACHE_FLAT, + .reg_defaults = rt6245_reg_defaults, + .num_reg_defaults = ARRAY_SIZE(rt6245_reg_defaults), + .reg_write = rt6245_reg_write, +}; + +static int rt6245_probe(struct i2c_client *i2c) +{ + struct rt6245_priv *priv; + struct regmap *regmap; + struct regulator_config regulator_cfg = {}; + struct regulator_dev *rdev; + int ret; + + priv = devm_kzalloc(&i2c->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->enable_state = true; + + priv->enable_gpio = devm_gpiod_get_optional(&i2c->dev, "enable", GPIOD_OUT_HIGH); + if (IS_ERR(priv->enable_gpio)) { + dev_err(&i2c->dev, "Failed to get 'enable' gpio\n"); + return PTR_ERR(priv->enable_gpio); + } + + usleep_range(RT6245_ENTIME_IN_US, RT6245_ENTIME_IN_US + 1000); + + regmap = devm_regmap_init(&i2c->dev, NULL, i2c, &rt6245_regmap_config); + if (IS_ERR(regmap)) { + dev_err(&i2c->dev, "Failed to initialize the regmap\n"); + return PTR_ERR(regmap); + } + + ret = rt6245_init_device_properties(&i2c->dev); + if (ret) { + dev_err(&i2c->dev, "Failed to initialize device properties\n"); + return ret; + } + + regulator_cfg.dev = &i2c->dev; + regulator_cfg.of_node = i2c->dev.of_node; + regulator_cfg.regmap = regmap; + regulator_cfg.driver_data = priv; + regulator_cfg.init_data = of_get_regulator_init_data(&i2c->dev, i2c->dev.of_node, + &rt6245_regulator_desc); + rdev = devm_regulator_register(&i2c->dev, &rt6245_regulator_desc, ®ulator_cfg); + if (IS_ERR(rdev)) { + dev_err(&i2c->dev, "Failed to register regulator\n"); + return PTR_ERR(rdev); + } + + return 0; +} + +static const struct of_device_id __maybe_unused rt6245_of_match_table[] = { + { .compatible = "richtek,rt6245", }, + {} +}; +MODULE_DEVICE_TABLE(of, rt6245_of_match_table); + +static struct i2c_driver rt6245_driver = { + .driver = { + .name = "rt6245", + .of_match_table = rt6245_of_match_table, + }, + .probe_new = rt6245_probe, +}; +module_i2c_driver(rt6245_driver); + +MODULE_AUTHOR("ChiYuan Huang <cy_huang@richtek.com>"); +MODULE_DESCRIPTION("Richtek RT6245 Regulator Driver"); +MODULE_LICENSE("GPL v2"); |