Re: [PATCH 4/8] iio: rework sampling rate setting in hmc5843

[Jonathan Cameron <jic23@kernel.org>]

On 5/8/2012 11:20 PM, Peter Meerwald wrote:
> From: Peter Meerwald<p.meerwald@bct-electronic.com>
>
> Signed-off-by: Peter Meerwald<pmeerw@pmeerw.net>
Acked-by: Jonathan Cameron <jic23@kernel.org>
> ---
>   drivers/staging/iio/magnetometer/hmc5843.c |   51 +++++++++++++---------------
>   1 files changed, 24 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/staging/iio/magnetometer/hmc5843.c b/drivers/staging/iio/magnetometer/hmc5843.c
> index 1318f7d..6888e04 100644
> --- a/drivers/staging/iio/magnetometer/hmc5843.c
> +++ b/drivers/staging/iio/magnetometer/hmc5843.c
> @@ -85,14 +85,6 @@
>    */
>   #define HMC5843_RATE_OFFSET			0x02
>   #define HMC5843_RATE_BITMASK			0x1C
> -#define RATE_5					0x00
> -#define RATE_10					0x01
> -#define RATE_20					0x02
> -#define RATE_50					0x03
> -#define RATE_100				0x04
> -#define RATE_200				0x05
> -#define RATE_500				0x06
> -
>   #define HMC5843_RATE_NOT_USED			0x07
>
>   /*
> @@ -342,6 +334,21 @@ static s32 hmc5843_set_rate(struct i2c_client *client,
>   	return i2c_smbus_write_byte_data(client, HMC5843_CONFIG_REG_A, reg_val);
>   }
>
> +static int hmc5843_check_sampling_frequency(struct hmc5843_data *data,
> +						const char *buf)
> +{
> +	const char * const *samp_freq = regval_to_samp_freq;
> +	int i;
> +
> +	for (i = 0; i<  HMC5843_RATE_NOT_USED; i++) {
> +		if (strncmp(buf, samp_freq[i],
> +			strlen(samp_freq[i])) == 0)
> +			return i;
> +	}
> +
> +	return -EINVAL;
> +}
> +
>   static ssize_t set_sampling_frequency(struct device *dev,
>   					struct device_attribute *attr,
>   					const char *buf, size_t count)
> @@ -350,27 +357,17 @@ static ssize_t set_sampling_frequency(struct device *dev,
>   	struct iio_dev *indio_dev = dev_get_drvdata(dev);
>   	struct i2c_client *client = to_i2c_client(indio_dev->dev.parent);
>   	struct hmc5843_data *data = iio_priv(indio_dev);
> -	unsigned long rate = 0;
> -
> -	if (strncmp(buf, "0.5" , 3) == 0)
> -		rate = RATE_5;
> -	else if (strncmp(buf, "1" , 1) == 0)
> -		rate = RATE_10;
> -	else if (strncmp(buf, "2", 1) == 0)
> -		rate = RATE_20;
> -	else if (strncmp(buf, "5", 1) == 0)
> -		rate = RATE_50;
> -	else if (strncmp(buf, "10", 2) == 0)
> -		rate = RATE_100;
> -	else if (strncmp(buf, "20" , 2) == 0)
> -		rate = RATE_200;
> -	else if (strncmp(buf, "50" , 2) == 0)
> -		rate = RATE_500;
> -	else
> -		return -EINVAL;
> +	int rate;
> +
> +	rate = hmc5843_check_sampling_frequency(data, buf);
> +	if (rate<  0) {
> +		dev_err(&client->dev,
> +			"sampling frequency is not supported\n");
> +		return rate;
> +	}
>
>   	mutex_lock(&data->lock);
> -	dev_dbg(dev, "set rate to %lu\n", rate);
> +	dev_dbg(dev, "set rate to %d\n", rate);
>   	if (hmc5843_set_rate(client, rate)) {
>   		count = -EINVAL;
>   		goto exit;