| Message ID | 20190207215036.185561-1-brandon.maier@rockwellcollins.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | hwmon: (ad7418) Catch I2C errors | expand |
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@rockwellcollins.com> 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);
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);