On Thu, Feb 07, 2019 at 03:50:36PM -0600, Brandon Maier wrote:
> If there is an i2c failure, the ad7416 reports its temperature as 0C.
> Return an error code so users can properly detect errors.
>
> Signed-off-by: Brandon Maier <brandon.maier@xxxxxxxxxxxxxxxxxxx>
Applied to hwmon-next.
Thanks,
Guenter
> ---
> Tested on an ad7416, attempting to `cat` the temp1_input while the
> sensor is physically disconnected returns this:
>
> > cat: read error: Remote I/O error
> ---
> drivers/hwmon/ad7418.c | 65 +++++++++++++++++++++++++++++++-----------
> 1 file changed, 49 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/hwmon/ad7418.c b/drivers/hwmon/ad7418.c
> index 76f0a5c01e8a..28a91d14d7af 100644
> --- a/drivers/hwmon/ad7418.c
> +++ b/drivers/hwmon/ad7418.c
> @@ -54,10 +54,11 @@ struct ad7418_data {
> u16 in[4];
> };
>
> -static struct ad7418_data *ad7418_update_device(struct device *dev)
> +static int ad7418_update_device(struct device *dev)
> {
> struct ad7418_data *data = dev_get_drvdata(dev);
> struct i2c_client *client = data->client;
> + s32 val;
>
> mutex_lock(&data->lock);
>
> @@ -67,47 +68,74 @@ static struct ad7418_data *ad7418_update_device(struct device *dev)
> int i, ch;
>
> /* read config register and clear channel bits */
> - cfg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
> + val = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
> + if (val < 0)
> + goto abort;
> +
> + cfg = val;
> cfg &= 0x1F;
>
> - i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
> + val = i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
> cfg | AD7418_CH_TEMP);
> + if (val < 0)
> + goto abort;
> +
> udelay(30);
>
> for (i = 0; i < 3; i++) {
> - data->temp[i] =
> - i2c_smbus_read_word_swapped(client,
> - AD7418_REG_TEMP[i]);
> + val = i2c_smbus_read_word_swapped(client,
> + AD7418_REG_TEMP[i]);
> + if (val < 0)
> + goto abort;
> +
> + data->temp[i] = val;
> }
>
> for (i = 0, ch = 4; i < data->adc_max; i++, ch--) {
> - i2c_smbus_write_byte_data(client,
> - AD7418_REG_CONF,
> - cfg | AD7418_REG_ADC_CH(ch));
> + val = i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
> + cfg | AD7418_REG_ADC_CH(ch));
> + if (val < 0)
> + goto abort;
>
> udelay(15);
> - data->in[data->adc_max - 1 - i] =
> - i2c_smbus_read_word_swapped(client,
> - AD7418_REG_ADC);
> + val = i2c_smbus_read_word_swapped(client,
> + AD7418_REG_ADC);
> + if (val < 0)
> + goto abort;
> +
> + data->in[data->adc_max - 1 - i] = val;
> }
>
> /* restore old configuration value */
> - i2c_smbus_write_word_swapped(client, AD7418_REG_CONF, cfg);
> + val = i2c_smbus_write_word_swapped(client, AD7418_REG_CONF,
> + cfg);
> + if (val < 0)
> + goto abort;
>
> data->last_updated = jiffies;
> data->valid = 1;
> }
>
> mutex_unlock(&data->lock);
> + return 0;
>
> - return data;
> +abort:
> + data->valid = 0;
> + mutex_unlock(&data->lock);
> + return val;
> }
>
> static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
> char *buf)
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> - struct ad7418_data *data = ad7418_update_device(dev);
> + struct ad7418_data *data = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = ad7418_update_device(dev);
> + if (ret < 0)
> + return ret;
> +
> return sprintf(buf, "%d\n",
> LM75_TEMP_FROM_REG(data->temp[attr->index]));
> }
> @@ -116,7 +144,12 @@ static ssize_t adc_show(struct device *dev, struct device_attribute *devattr,
> char *buf)
> {
> struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
> - struct ad7418_data *data = ad7418_update_device(dev);
> + struct ad7418_data *data = dev_get_drvdata(dev);
> + int ret;
> +
> + ret = ad7418_update_device(dev);
> + if (ret < 0)
> + return ret;
>
> return sprintf(buf, "%d\n",
> ((data->in[attr->index] >> 6) * 2500 + 512) / 1024);
