staging: iio: rework sampling rate setting in hmc5843

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/iio/magnetometer/hmc5843.c b/drivers/staging/iio/magnetometer/hmc5843.c
index 27c5521b4e281d7d22fafb8193e9d8cea86729f2..cf2bab848717026f09ac6489314a6d272bf32dbf 100644 (file)
--- 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_to_iio_dev(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;