On Thu, Oct 14, 2021 at 03:09:08PM +0200, Krzysztof Adamski wrote: > Recent patch added possibility to disable selected channels. That would > only make sure that the ENODATA is returned for those channels but would > not configure the actual hardware. > > With this patch, the config register is written to make sure the > channels are disabled also at hardware level. > > Signed-off-by: Krzysztof Adamski <krzysztof.adamski@xxxxxxxxx> Applied, again after "s/^ / /" Guenter > --- > drivers/hwmon/tmp421.c | 44 ++++++++++++++++++++++++++++++++++++------ > 1 file changed, 38 insertions(+), 6 deletions(-) > > diff --git a/drivers/hwmon/tmp421.c b/drivers/hwmon/tmp421.c > index 606914f20910..b402e81ae5d5 100644 > --- a/drivers/hwmon/tmp421.c > +++ b/drivers/hwmon/tmp421.c > @@ -33,6 +33,9 @@ enum chips { tmp421, tmp422, tmp423, tmp441, tmp442 }; > /* The TMP421 registers */ > #define TMP421_STATUS_REG 0x08 > #define TMP421_CONFIG_REG_1 0x09 > +#define TMP421_CONFIG_REG_2 0x0A > +#define TMP421_CONFIG_REG_REN(x) (BIT(3 + (x))) > +#define TMP421_CONFIG_REG_REN_MASK GENMASK(6, 3) > #define TMP421_CONVERSION_RATE_REG 0x0B > #define TMP421_N_FACTOR_REG_1 0x21 > #define TMP421_MANUFACTURER_ID_REG 0xFE > @@ -162,6 +165,34 @@ static int tmp421_update_device(struct tmp421_data *data) > return 0; > } > > +static int tmp421_enable_channels(struct tmp421_data *data) > +{ > + int err; > + struct i2c_client *client = data->client; > + struct device *dev = &client->dev; > + int old = i2c_smbus_read_byte_data(client, TMP421_CONFIG_REG_2); > + int new, i; > + > + if (old < 0) { > + dev_err(dev, "error reading register, can't disable channels\n"); > + return old; > + } > + > + new = old & ~TMP421_CONFIG_REG_REN_MASK; > + for (i = 0; i < data->channels; i++) > + if (data->channel[i].enabled) > + new |= TMP421_CONFIG_REG_REN(i); > + > + if (new == old) > + return 0; > + > + err = i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_2, new); > + if (err < 0) > + dev_err(dev, "error writing register, can't disable channels\n"); > + > + return err; > +} > + > static int tmp421_read(struct device *dev, enum hwmon_sensor_types type, > u32 attr, int channel, long *val) > { > @@ -217,9 +248,10 @@ static umode_t tmp421_is_visible(const void *data, enum hwmon_sensor_types type, > } > } > > -static int tmp421_init_client(struct i2c_client *client) > +static int tmp421_init_client(struct tmp421_data *data) > { > int config, config_orig; > + struct i2c_client *client = data->client; > > /* Set the conversion rate to 2 Hz */ > i2c_smbus_write_byte_data(client, TMP421_CONVERSION_RATE_REG, 0x05); > @@ -240,7 +272,7 @@ static int tmp421_init_client(struct i2c_client *client) > i2c_smbus_write_byte_data(client, TMP421_CONFIG_REG_1, config); > } > > - return 0; > + return tmp421_enable_channels(data); > } > > static int tmp421_detect(struct i2c_client *client, > @@ -391,10 +423,6 @@ static int tmp421_probe(struct i2c_client *client) > data->channels = i2c_match_id(tmp421_id, client)->driver_data; > data->client = client; > > - err = tmp421_init_client(client); > - if (err) > - return err; > - > for (i = 0; i < data->channels; i++) { > data->temp_config[i] = HWMON_T_INPUT | HWMON_T_FAULT; > data->channel[i].enabled = true; > @@ -404,6 +432,10 @@ static int tmp421_probe(struct i2c_client *client) > if (err) > return err; > > + err = tmp421_init_client(data); > + if (err) > + return err; > + > data->chip.ops = &tmp421_ops; > data->chip.info = data->info; >