Re: [PATCH] staging:iio:tsl2x7x: Use iio_str_to_fixedpoint instead of open-coding it

[Jonathan Cameron <jic23@kernel.org>]

On 01/10/2013 04:18 PM, Lars-Peter Clausen wrote:
> The tsl2x7x driver has a copy'n'pasted version of the iio_str_to_fixedpoint()
> function from the IIO core. Replace this custom copy and use
> iio_str_to_fixedpoint instead.
> 
> The patch also introduces a slight functional change in that it makes sure that
> in case of a parsing error the error is reported back to userspace instead of
> silently ignoring it.
> 
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
I'm fine with this but ideally want an ack from Jon Brenner so will let it sit
for a while yet.

> ---
> Only compile tested.
> ---
>  drivers/staging/iio/light/tsl2x7x_core.c | 78 +++++---------------------------
>  1 file changed, 12 insertions(+), 66 deletions(-)
> 
> diff --git a/drivers/staging/iio/light/tsl2x7x_core.c b/drivers/staging/iio/light/tsl2x7x_core.c
> index 9e50fbba..a58731e 100644
> --- a/drivers/staging/iio/light/tsl2x7x_core.c
> +++ b/drivers/staging/iio/light/tsl2x7x_core.c
> @@ -292,59 +292,6 @@ static const u8 device_channel_config[] = {
>  };
>  
>  /**
> - * tsl2x7x_parse_buffer() - parse a decimal result from a buffer.
> - * @*buf:                   pointer to char buffer to parse
> - * @*result:                pointer to buffer to contain
> - *                          resulting interger / decimal as ints.
> - *
> - */
> -static int
> -tsl2x7x_parse_buffer(const char *buf, struct tsl2x7x_parse_result *result)
> -{
> -	int integer = 0, fract = 0, fract_mult = 100000;
> -	bool integer_part = true, negative = false;
> -
> -	if (buf[0] == '-') {
> -		negative = true;
> -		buf++;
> -	}
> -
> -	while (*buf) {
> -		if ('0' <= *buf && *buf <= '9') {
> -			if (integer_part)
> -				integer = integer*10 + *buf - '0';
> -			else {
> -				fract += fract_mult*(*buf - '0');
> -				if (fract_mult == 1)
> -					break;
> -				fract_mult /= 10;
> -			}
> -		} else if (*buf == '\n') {
> -			if (*(buf + 1) == '\0')
> -				break;
> -			else
> -				return -EINVAL;
> -		} else if (*buf == '.') {
> -			integer_part = false;
> -		} else {
> -			return -EINVAL;
> -		}
> -		buf++;
> -	}
> -	if (negative) {
> -		if (integer)
> -			integer = -integer;
> -		else
> -			fract = -fract;
> -	}
> -
> -	result->integer = integer;
> -	result->fract = fract;
> -
> -	return 0;
> -}
> -
> -/**
>   * tsl2x7x_i2c_read() - Read a byte from a register.
>   * @client:	i2c client
>   * @reg:	device register to read from
> @@ -1036,13 +983,12 @@ static ssize_t tsl2x7x_als_time_store(struct device *dev,
>  	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
>  	struct tsl2X7X_chip *chip = iio_priv(indio_dev);
>  	struct tsl2x7x_parse_result result;
> +	int ret;
>  
> -	result.integer = 0;
> -	result.fract = 0;
> -
> -	tsl2x7x_parse_buffer(buf, &result);
> +	ret = iio_str_to_fixpoint(buf, 100, &result.integer, &result.fract);
> +	if (ret)
> +		return ret;
>  
> -	result.fract /= 1000;
>  	result.fract /= 3;
>  	chip->tsl2x7x_settings.als_time =
>  			(TSL2X7X_MAX_TIMER_CNT - (u8)result.fract);
> @@ -1109,12 +1055,12 @@ static ssize_t tsl2x7x_als_persistence_store(struct device *dev,
>  	struct tsl2X7X_chip *chip = iio_priv(indio_dev);
>  	struct tsl2x7x_parse_result result;
>  	int y, z, filter_delay;
> +	int ret;
>  
> -	result.integer = 0;
> -	result.fract = 0;
> -	tsl2x7x_parse_buffer(buf, &result);
> +	ret = iio_str_to_fixpoint(buf, 100, &result.integer, &result.fract);
> +	if (ret)
> +		return ret;
>  
> -	result.fract /= 1000;
>  	y = (TSL2X7X_MAX_TIMER_CNT - (u8)chip->tsl2x7x_settings.als_time) + 1;
>  	z = y * TSL2X7X_MIN_ITIME;
>  
> @@ -1155,12 +1101,12 @@ static ssize_t tsl2x7x_prox_persistence_store(struct device *dev,
>  	struct tsl2X7X_chip *chip = iio_priv(indio_dev);
>  	struct tsl2x7x_parse_result result;
>  	int y, z, filter_delay;
> +	int ret;
>  
> -	result.integer = 0;
> -	result.fract = 0;
> -	tsl2x7x_parse_buffer(buf, &result);
> +	ret = iio_str_to_fixpoint(buf, 100, &result.integer, &result.fract);
> +	if (ret)
> +		return ret;
>  
> -	result.fract /= 1000;
>  	y = (TSL2X7X_MAX_TIMER_CNT - (u8)chip->tsl2x7x_settings.prx_time) + 1;
>  	z = y * TSL2X7X_MIN_ITIME;
>  
>