Re: [PATCH v2 3/5] iio:light:stk3310: add more error handling

[Jonathan Cameron <jic23@kernel.org>]

On 09/07/15 22:51, Hartmut Knaack wrote:
> Check for the following error cases:
>   * lower boundary for val in _write_event
>   * return value of regmap_(field_)read
>   * possible values for chan->type
>   * return value of stk3310_gpio_probe
> 
> Also add an error path in _probe to put the sensor back into stand-by mode
> in case of serious errors.
> 
> Signed-off-by: Hartmut Knaack <knaack.h@gmx.de>
looks good.  Will have to hold it until the fixes have worked there way
through though.
> ---
>  drivers/iio/light/stk3310.c | 59 ++++++++++++++++++++++++++++++++++-----------
>  1 file changed, 45 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/iio/light/stk3310.c b/drivers/iio/light/stk3310.c
> index 11a027adc204..d6df40220007 100644
> --- a/drivers/iio/light/stk3310.c
> +++ b/drivers/iio/light/stk3310.c
> @@ -241,8 +241,11 @@ static int stk3310_write_event(struct iio_dev *indio_dev,
>  	struct stk3310_data *data = iio_priv(indio_dev);
>  	struct i2c_client *client = data->client;
>  
> -	regmap_field_read(data->reg_ps_gain, &index);
> -	if (val > stk3310_ps_max[index])
> +	ret = regmap_field_read(data->reg_ps_gain, &index);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (val < 0 || val > stk3310_ps_max[index])
>  		return -EINVAL;
>  
>  	if (dir == IIO_EV_DIR_RISING)
> @@ -266,9 +269,12 @@ static int stk3310_read_event_config(struct iio_dev *indio_dev,
>  				     enum iio_event_direction dir)
>  {
>  	unsigned int event_val;
> +	int ret;
>  	struct stk3310_data *data = iio_priv(indio_dev);
>  
> -	regmap_field_read(data->reg_int_ps, &event_val);
> +	ret = regmap_field_read(data->reg_int_ps, &event_val);
> +	if (ret < 0)
> +		return ret;
>  
>  	return event_val;
>  }
> @@ -307,14 +313,16 @@ static int stk3310_read_raw(struct iio_dev *indio_dev,
>  	struct stk3310_data *data = iio_priv(indio_dev);
>  	struct i2c_client *client = data->client;
>  
> +	if (chan->type != IIO_LIGHT && chan->type != IIO_PROXIMITY)
> +		return -EINVAL;
> +
>  	switch (mask) {
>  	case IIO_CHAN_INFO_RAW:
>  		if (chan->type == IIO_LIGHT)
>  			reg = STK3310_REG_ALS_DATA_MSB;
> -		else if (chan->type == IIO_PROXIMITY)
> -			reg = STK3310_REG_PS_DATA_MSB;
>  		else
> -			return -EINVAL;
> +			reg = STK3310_REG_PS_DATA_MSB;
> +
>  		mutex_lock(&data->lock);
>  		ret = regmap_bulk_read(data->regmap, reg, &buf, 2);
>  		if (ret < 0) {
> @@ -327,17 +335,23 @@ static int stk3310_read_raw(struct iio_dev *indio_dev,
>  		return IIO_VAL_INT;
>  	case IIO_CHAN_INFO_INT_TIME:
>  		if (chan->type == IIO_LIGHT)
> -			regmap_field_read(data->reg_als_it, &index);
> +			ret = regmap_field_read(data->reg_als_it, &index);
>  		else
> -			regmap_field_read(data->reg_ps_it, &index);
> +			ret = regmap_field_read(data->reg_ps_it, &index);
> +		if (ret < 0)
> +			return ret;
> +
>  		*val = stk3310_it_table[index][0];
>  		*val2 = stk3310_it_table[index][1];
>  		return IIO_VAL_INT_PLUS_MICRO;
>  	case IIO_CHAN_INFO_SCALE:
>  		if (chan->type == IIO_LIGHT)
> -			regmap_field_read(data->reg_als_gain, &index);
> +			ret = regmap_field_read(data->reg_als_gain, &index);
>  		else
> -			regmap_field_read(data->reg_ps_gain, &index);
> +			ret = regmap_field_read(data->reg_ps_gain, &index);
> +		if (ret < 0)
> +			return ret;
> +
>  		*val = stk3310_scale_table[index][0];
>  		*val2 = stk3310_scale_table[index][1];
>  		return IIO_VAL_INT_PLUS_MICRO;
> @@ -354,6 +368,9 @@ static int stk3310_write_raw(struct iio_dev *indio_dev,
>  	int index;
>  	struct stk3310_data *data = iio_priv(indio_dev);
>  
> +	if (chan->type != IIO_LIGHT && chan->type != IIO_PROXIMITY)
> +		return -EINVAL;
> +
>  	switch (mask) {
>  	case IIO_CHAN_INFO_INT_TIME:
>  		index = stk3310_get_index(stk3310_it_table,
> @@ -435,7 +452,10 @@ static int stk3310_init(struct iio_dev *indio_dev)
>  	struct stk3310_data *data = iio_priv(indio_dev);
>  	struct i2c_client *client = data->client;
>  
> -	regmap_read(data->regmap, STK3310_REG_ID, &chipid);
> +	ret = regmap_read(data->regmap, STK3310_REG_ID, &chipid);
> +	if (ret < 0)
> +		return ret;
> +
>  	if (chipid != STK3310_CHIP_ID_VAL &&
>  	    chipid != STK3311_CHIP_ID_VAL) {
>  		dev_err(&client->dev, "invalid chip id: 0x%x\n", chipid);
> @@ -608,8 +628,13 @@ static int stk3310_probe(struct i2c_client *client,
>  	if (ret < 0)
>  		return ret;
>  
> -	if (client->irq < 0)
> +	if (client->irq < 0) {
>  		client->irq = stk3310_gpio_probe(client);
> +		if (client->irq < 0) {
> +			ret = client->irq;
> +			goto err_standby;
> +		}
> +	}
>  
>  	if (client->irq >= 0) {
>  		ret = devm_request_threaded_irq(&client->dev, client->irq,
> @@ -618,17 +643,23 @@ static int stk3310_probe(struct i2c_client *client,
>  						IRQF_TRIGGER_FALLING |
>  						IRQF_ONESHOT,
>  						STK3310_EVENT, indio_dev);
> -		if (ret < 0)
> +		if (ret < 0) {
>  			dev_err(&client->dev, "request irq %d failed\n",
>  					client->irq);
> +			goto err_standby;
> +		}
>  	}
>  
>  	ret = iio_device_register(indio_dev);
>  	if (ret < 0) {
>  		dev_err(&client->dev, "device_register failed\n");
> -		stk3310_set_state(data, STK3310_STATE_STANDBY);
> +		goto err_standby;
>  	}
>  
> +	return 0;
> +
> +err_standby:
> +	stk3310_set_state(data, STK3310_STATE_STANDBY);
>  	return ret;
>  }
>  
>