From bea0bab0fcf5a0b97f3545ba35647f0f37dc2475 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Fri, 16 Jan 2015 10:08:27 -0800 Subject: [PATCH] hwmon: (ads2828) Convert to use regmap Simplify code and reduce code size by using regmap to access i2c registers. Reviewed-and-Tested-by: Robert Rosengren Signed-off-by: Guenter Roeck --- drivers/hwmon/Kconfig | 1 + drivers/hwmon/ads7828.c | 70 ++++++++++++++++++------------------------------- 2 files changed, 27 insertions(+), 44 deletions(-) diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index c243940..d931cbb 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -1389,6 +1389,7 @@ config SENSORS_ADS1015 config SENSORS_ADS7828 tristate "Texas Instruments ADS7828 and compatibles" depends on I2C + select REGMAP_I2C help If you say yes here you get support for Texas Instruments ADS7828 and ADS7830 8-channel A/D converters. ADS7828 resolution is 12-bit, while diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c index a622d40..071f779 100644 --- a/drivers/hwmon/ads7828.c +++ b/drivers/hwmon/ads7828.c @@ -30,14 +30,12 @@ #include #include #include -#include #include -#include #include +#include #include /* The ADS7828 registers */ -#define ADS7828_NCH 8 /* 8 channels supported */ #define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */ #define ADS7828_CMD_PD1 0x04 /* Internal vref OFF && A/D ON */ #define ADS7828_CMD_PD3 0x0C /* Internal vref ON && A/D ON */ @@ -50,17 +48,12 @@ enum ads7828_chips { ads7828, ads7830 }; /* Client specific data */ struct ads7828_data { - struct i2c_client *client; - struct mutex update_lock; /* Mutex protecting updates */ - unsigned long last_updated; /* Last updated time (in jiffies) */ - u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH samples */ - bool valid; /* Validity flag */ + struct regmap *regmap; bool diff_input; /* Differential input */ bool ext_vref; /* External voltage reference */ unsigned int vref_mv; /* voltage reference value */ u8 cmd_byte; /* Command byte without channel bits */ unsigned int lsb_resol; /* Resolution of the ADC sample LSB */ - s32 (*read_channel)(const struct i2c_client *client, u8 command); }; /* Command byte C2,C1,C0 - see datasheet */ @@ -69,42 +62,22 @@ static inline u8 ads7828_cmd_byte(u8 cmd, int ch) return cmd | (((ch >> 1) | (ch & 0x01) << 2) << 4); } -/* Update data for the device (all 8 channels) */ -static struct ads7828_data *ads7828_update_device(struct device *dev) -{ - struct ads7828_data *data = dev_get_drvdata(dev); - struct i2c_client *client = data->client; - - mutex_lock(&data->update_lock); - - if (time_after(jiffies, data->last_updated + HZ + HZ / 2) - || !data->valid) { - unsigned int ch; - dev_dbg(&client->dev, "Starting ads7828 update\n"); - - for (ch = 0; ch < ADS7828_NCH; ch++) { - u8 cmd = ads7828_cmd_byte(data->cmd_byte, ch); - data->adc_input[ch] = data->read_channel(client, cmd); - } - data->last_updated = jiffies; - data->valid = true; - } - - mutex_unlock(&data->update_lock); - - return data; -} - /* sysfs callback function */ static ssize_t ads7828_show_in(struct device *dev, struct device_attribute *da, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); - struct ads7828_data *data = ads7828_update_device(dev); - unsigned int value = DIV_ROUND_CLOSEST(data->adc_input[attr->index] * - data->lsb_resol, 1000); + struct ads7828_data *data = dev_get_drvdata(dev); + u8 cmd = ads7828_cmd_byte(data->cmd_byte, attr->index); + unsigned int regval; + int err; - return sprintf(buf, "%d\n", value); + err = regmap_read(data->regmap, cmd, ®val); + if (err < 0) + return err; + + return sprintf(buf, "%d\n", + DIV_ROUND_CLOSEST(regval * data->lsb_resol, 1000)); } static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ads7828_show_in, NULL, 0); @@ -130,6 +103,16 @@ static struct attribute *ads7828_attrs[] = { ATTRIBUTE_GROUPS(ads7828); +static const struct regmap_config ads2828_regmap_config = { + .reg_bits = 8, + .val_bits = 16, +}; + +static const struct regmap_config ads2830_regmap_config = { + .reg_bits = 8, + .val_bits = 8, +}; + static int ads7828_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -160,19 +143,18 @@ static int ads7828_probe(struct i2c_client *client, /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */ if (id->driver_data == ads7828) { data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 4096); - data->read_channel = i2c_smbus_read_word_swapped; + data->regmap = devm_regmap_init_i2c(client, + &ads2828_regmap_config); } else { data->lsb_resol = DIV_ROUND_CLOSEST(data->vref_mv * 1000, 256); - data->read_channel = i2c_smbus_read_byte_data; + data->regmap = devm_regmap_init_i2c(client, + &ads2830_regmap_config); } data->cmd_byte = data->ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3; if (!data->diff_input) data->cmd_byte |= ADS7828_CMD_SD_SE; - data->client = client; - mutex_init(&data->update_lock); - hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, data, ads7828_groups); -- 2.7.4