diff options
Diffstat (limited to 'drivers/hwmon/ads7828.c')
| -rw-r--r-- | drivers/hwmon/ads7828.c | 102 |
1 files changed, 40 insertions, 62 deletions
diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c index a622d40eec17..bce4e9ff21bf 100644 --- a/drivers/hwmon/ads7828.c +++ b/drivers/hwmon/ads7828.c @@ -30,14 +30,12 @@ #include <linux/hwmon-sysfs.h> #include <linux/i2c.h> #include <linux/init.h> -#include <linux/jiffies.h> #include <linux/module.h> -#include <linux/mutex.h> #include <linux/platform_data/ads7828.h> +#include <linux/regmap.h> #include <linux/slab.h> /* 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 +48,9 @@ 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 */ - bool diff_input; /* Differential input */ - bool ext_vref; /* External voltage reference */ - unsigned int vref_mv; /* voltage reference value */ + struct regmap *regmap; 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 +59,22 @@ 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 +100,16 @@ 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) { @@ -137,42 +117,40 @@ static int ads7828_probe(struct i2c_client *client, struct ads7828_platform_data *pdata = dev_get_platdata(dev); struct ads7828_data *data; struct device *hwmon_dev; + unsigned int vref_mv = ADS7828_INT_VREF_MV; + bool diff_input = false; + bool ext_vref = false; data = devm_kzalloc(dev, sizeof(struct ads7828_data), GFP_KERNEL); if (!data) return -ENOMEM; if (pdata) { - data->diff_input = pdata->diff_input; - data->ext_vref = pdata->ext_vref; - if (data->ext_vref) - data->vref_mv = pdata->vref_mv; + diff_input = pdata->diff_input; + ext_vref = pdata->ext_vref; + if (ext_vref && pdata->vref_mv) + vref_mv = pdata->vref_mv; } - /* Bound Vref with min/max values if it was provided */ - if (data->vref_mv) - data->vref_mv = clamp_val(data->vref_mv, - ADS7828_EXT_VREF_MV_MIN, - ADS7828_EXT_VREF_MV_MAX); - else - data->vref_mv = ADS7828_INT_VREF_MV; + /* Bound Vref with min/max values */ + vref_mv = clamp_val(vref_mv, ADS7828_EXT_VREF_MV_MIN, + ADS7828_EXT_VREF_MV_MAX); /* 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->lsb_resol = DIV_ROUND_CLOSEST(vref_mv * 1000, 4096); + 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->lsb_resol = DIV_ROUND_CLOSEST(vref_mv * 1000, 256); + 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 = ext_vref ? ADS7828_CMD_PD1 : ADS7828_CMD_PD3; + if (!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); |