diff options
Diffstat (limited to 'drivers/regulator/max5970-regulator.c')
| -rw-r--r-- | drivers/regulator/max5970-regulator.c | 147 |
1 files changed, 144 insertions, 3 deletions
diff --git a/drivers/regulator/max5970-regulator.c b/drivers/regulator/max5970-regulator.c index b56a174cde..830a1c4cd7 100644 --- a/drivers/regulator/max5970-regulator.c +++ b/drivers/regulator/max5970-regulator.c @@ -10,6 +10,7 @@ #include <linux/bitops.h> #include <linux/device.h> #include <linux/err.h> +#include <linux/hwmon.h> #include <linux/module.h> #include <linux/io.h> #include <linux/of.h> @@ -32,6 +33,132 @@ enum max597x_regulator_id { MAX597X_SW1, }; +static int max5970_read_adc(struct regmap *regmap, int reg, long *val) +{ + u8 reg_data[2]; + int ret; + + ret = regmap_bulk_read(regmap, reg, ®_data[0], 2); + if (ret < 0) + return ret; + + *val = (reg_data[0] << 2) | (reg_data[1] & 3); + + return 0; +} + +static int max5970_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + struct regulator_dev **rdevs = dev_get_drvdata(dev); + struct max5970_regulator *ddata = rdev_get_drvdata(rdevs[channel]); + struct regmap *regmap = ddata->regmap; + int ret; + + switch (type) { + case hwmon_curr: + switch (attr) { + case hwmon_curr_input: + ret = max5970_read_adc(regmap, MAX5970_REG_CURRENT_H(channel), val); + if (ret < 0) + return ret; + /* + * Calculate current from ADC value, IRNG range & shunt resistor value. + * ddata->irng holds the voltage corresponding to the maximum value the + * 10-bit ADC can measure. + * To obtain the output, multiply the ADC value by the IRNG range (in + * millivolts) and then divide it by the maximum value of the 10-bit ADC. + */ + *val = (*val * ddata->irng) >> 10; + /* Convert the voltage meansurement across shunt resistor to current */ + *val = (*val * 1000) / ddata->shunt_micro_ohms; + return 0; + default: + return -EOPNOTSUPP; + } + + case hwmon_in: + switch (attr) { + case hwmon_in_input: + ret = max5970_read_adc(regmap, MAX5970_REG_VOLTAGE_H(channel), val); + if (ret < 0) + return ret; + /* + * Calculate voltage from ADC value and MON range. + * ddata->mon_rng holds the voltage corresponding to the maximum value the + * 10-bit ADC can measure. + * To obtain the output, multiply the ADC value by the MON range (in + * microvolts) and then divide it by the maximum value of the 10-bit ADC. + */ + *val = mul_u64_u32_shr(*val, ddata->mon_rng, 10); + /* uV to mV */ + *val = *val / 1000; + return 0; + default: + return -EOPNOTSUPP; + } + default: + return -EOPNOTSUPP; + } +} + +static umode_t max5970_is_visible(const void *data, + enum hwmon_sensor_types type, + u32 attr, int channel) +{ + struct regulator_dev **rdevs = (struct regulator_dev **)data; + struct max5970_regulator *ddata; + + if (channel >= MAX5970_NUM_SWITCHES || !rdevs[channel]) + return 0; + + ddata = rdev_get_drvdata(rdevs[channel]); + + if (channel >= ddata->num_switches) + return 0; + + switch (type) { + case hwmon_in: + switch (attr) { + case hwmon_in_input: + return 0444; + default: + break; + } + break; + case hwmon_curr: + switch (attr) { + case hwmon_curr_input: + /* Current measurement requires knowledge of the shunt resistor value. */ + if (ddata->shunt_micro_ohms) + return 0444; + break; + default: + break; + } + break; + default: + break; + } + return 0; +} + +static const struct hwmon_ops max5970_hwmon_ops = { + .is_visible = max5970_is_visible, + .read = max5970_read, +}; + +static const struct hwmon_channel_info *max5970_info[] = { + HWMON_CHANNEL_INFO(in, HWMON_I_INPUT, HWMON_I_INPUT), + HWMON_CHANNEL_INFO(curr, HWMON_C_INPUT, HWMON_C_INPUT), + NULL +}; + +static const struct hwmon_chip_info max5970_chip_info = { + .ops = &max5970_hwmon_ops, + .info = max5970_info, +}; + static int max597x_uvp_ovp_check_mode(struct regulator_dev *rdev, int severity) { int ret, reg; @@ -265,7 +392,7 @@ static int max597x_regmap_read_clear(struct regmap *map, unsigned int reg, return ret; if (*val) - return regmap_write(map, reg, *val); + return regmap_write(map, reg, 0); return 0; } @@ -431,7 +558,8 @@ static int max597x_regulator_probe(struct platform_device *pdev) struct i2c_client *i2c = to_i2c_client(pdev->dev.parent); struct regulator_config config = { }; struct regulator_dev *rdev; - struct regulator_dev *rdevs[MAX5970_NUM_SWITCHES]; + struct regulator_dev **rdevs = NULL; + struct device *hwmon_dev; int num_switches; int ret, i; @@ -442,6 +570,11 @@ static int max597x_regulator_probe(struct platform_device *pdev) if (!max597x) return -ENOMEM; + rdevs = devm_kcalloc(&i2c->dev, MAX5970_NUM_SWITCHES, sizeof(struct regulator_dev *), + GFP_KERNEL); + if (!rdevs) + return -ENOMEM; + i2c_set_clientdata(i2c, max597x); if (of_device_is_compatible(i2c->dev.of_node, "maxim,max5978")) @@ -451,7 +584,6 @@ static int max597x_regulator_probe(struct platform_device *pdev) else return -ENODEV; - i2c_set_clientdata(i2c, max597x); num_switches = max597x->num_switches; for (i = 0; i < num_switches; i++) { @@ -485,6 +617,15 @@ static int max597x_regulator_probe(struct platform_device *pdev) max597x->shunt_micro_ohms[i] = data->shunt_micro_ohms; } + if (IS_REACHABLE(CONFIG_HWMON)) { + hwmon_dev = devm_hwmon_device_register_with_info(&i2c->dev, "max5970", rdevs, + &max5970_chip_info, NULL); + if (IS_ERR(hwmon_dev)) { + return dev_err_probe(&i2c->dev, PTR_ERR(hwmon_dev), + "Unable to register hwmon device\n"); + } + } + if (i2c->irq) { ret = max597x_setup_irq(&i2c->dev, i2c->irq, rdevs, num_switches, |