staging:iio:hmc5843: Use INFO_SAMP_FREQ

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/staging/iio/magnetometer/hmc5843.c

@@ -165,18 +165,19 @@ static const int hmc5883l_regval_to_input_field_mga[] = {
  * 6		| 50			| 75
  * 7		| Not used		| Not used
  */
-static const char * const hmc5843_regval_to_sample_freq[] = {
-	"0.5", "1", "2", "5", "10", "20", "50",
+static const int hmc5843_regval_to_samp_freq[7][2] = {
+	{0, 500000}, {1, 0}, {2, 0}, {5, 0}, {10, 0}, {20, 0}, {50, 0}
 };
 
-static const char * const hmc5883_regval_to_sample_freq[] = {
-	"0.75", "1.5", "3", "7.5", "15", "30", "75",
+static const int hmc5883_regval_to_samp_freq[7][2] = {
+	{0, 750000}, {1, 500000}, {3, 0}, {7, 500000}, {15, 0}, {30, 0},
+	{75, 0}
 };
 
 /* Describe chip variants */
 struct hmc5843_chip_info {
 	const struct iio_chan_spec *channels;
-	const char * const *regval_to_sample_freq;
+	const int (*regval_to_samp_freq)[2];
 	const int *regval_to_input_field_mga;
 	const int *regval_to_nanoscale;
 };
@@ -370,17 +371,17 @@ static IIO_DEVICE_ATTR(meas_conf,
 			hmc5843_set_measurement_configuration,
 			0);
 
-static ssize_t hmc5843_show_sampling_frequencies_available(struct device *dev,
-						struct device_attribute *attr,
-						char *buf)
+static ssize_t hmc5843_show_samp_freq_avail(struct device *dev,
+				struct device_attribute *attr, char *buf)
 {
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct hmc5843_data *data = iio_priv(indio_dev);
+	struct hmc5843_data *data = iio_priv(dev_to_iio_dev(dev));
 	ssize_t total_n = 0;
 	int i;
 
 	for (i = 0; i < HMC5843_RATE_NOT_USED; i++) {
-		ssize_t n = sprintf(buf, "%s ", data->variant->regval_to_sample_freq[i]);
+		ssize_t n = sprintf(buf, "%d.%d ",
+			data->variant->regval_to_samp_freq[i][0],
+			data->variant->regval_to_samp_freq[i][1]);
 		buf += n;
 		total_n += n;
 	}
@@ -390,87 +391,30 @@ static ssize_t hmc5843_show_sampling_frequencies_available(struct device *dev,
 	return total_n;
 }
 
-static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(hmc5843_show_sampling_frequencies_available);
+static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(hmc5843_show_samp_freq_avail);
 
 static s32 hmc5843_set_rate(struct hmc5843_data *data, u8 rate)
 {
-	u8 reg_val;
-
-	if (rate >= HMC5843_RATE_NOT_USED) {
-		dev_err(&data->client->dev,
-			"data output rate is not supported\n");
-		return -EINVAL;
-	}
+	u8 reg_val = data->meas_conf | (rate << HMC5843_RATE_OFFSET);
 
-	reg_val = data->meas_conf | (rate << HMC5843_RATE_OFFSET);
 	return i2c_smbus_write_byte_data(data->client, HMC5843_CONFIG_REG_A,
 		reg_val);
 }
 
-static int hmc5843_check_sampling_frequency(struct hmc5843_data *data,
-						const char *buf)
+static int hmc5843_check_samp_freq(struct hmc5843_data *data,
+				   int val, int val2)
 {
-	const char * const *samp_freq = data->variant->regval_to_sample_freq;
 	int i;
 
 	for (i = 0; i < HMC5843_RATE_NOT_USED; i++) {
-		if (sysfs_streq(buf, samp_freq[i]))
+		if (val == data->variant->regval_to_samp_freq[i][0] &&
+		    val2 == data->variant->regval_to_samp_freq[i][1])
 			return i;
 	}
 
 	return -EINVAL;
 }
 
-static ssize_t hmc5843_set_sampling_frequency(struct device *dev,
-					struct device_attribute *attr,
-					const char *buf, size_t count)
-{
-
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct hmc5843_data *data = iio_priv(indio_dev);
-	int rate;
-
-	rate = hmc5843_check_sampling_frequency(data, buf);
-	if (rate < 0) {
-		dev_err(&data->client->dev,
-			"sampling frequency is not supported\n");
-		return rate;
-	}
-
-	mutex_lock(&data->lock);
-	dev_dbg(dev, "set rate to %d\n", rate);
-	if (hmc5843_set_rate(data, rate)) {
-		count = -EINVAL;
-		goto exit;
-	}
-	data->rate = rate;
-
-exit:
-	mutex_unlock(&data->lock);
-	return count;
-}
-
-static ssize_t hmc5843_show_sampling_frequency(struct device *dev,
-			struct device_attribute *attr, char *buf)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
-	struct hmc5843_data *data = iio_priv(indio_dev);
-	s32 rate;
-
-	rate = i2c_smbus_read_byte_data(data->client, this_attr->address);
-	if (rate < 0)
-		return rate;
-	rate = (rate & HMC5843_RATE_BITMASK) >> HMC5843_RATE_OFFSET;
-	return sprintf(buf, "%s\n", data->variant->regval_to_sample_freq[rate]);
-}
-
-static IIO_DEVICE_ATTR(sampling_frequency,
-			S_IWUSR | S_IRUGO,
-			hmc5843_show_sampling_frequency,
-			hmc5843_set_sampling_frequency,
-			HMC5843_CONFIG_REG_A);
-
 static ssize_t hmc5843_show_range_gain(struct device *dev,
 				struct device_attribute *attr,
 				char *buf)
@@ -525,8 +469,7 @@ static IIO_DEVICE_ATTR(in_magn_range,
 
 static int hmc5843_read_raw(struct iio_dev *indio_dev,
 			    struct iio_chan_spec const *chan,
-			    int *val, int *val2,
-			    long mask)
+			    int *val, int *val2, long mask)
 {
 	struct hmc5843_data *data = iio_priv(indio_dev);
 
@@ -537,17 +480,47 @@ static int hmc5843_read_raw(struct iio_dev *indio_dev,
 		*val = 0;
 		*val2 = data->variant->regval_to_nanoscale[data->range];
 		return IIO_VAL_INT_PLUS_NANO;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val = data->variant->regval_to_samp_freq[data->rate][0];
+		*val2 = data->variant->regval_to_samp_freq[data->rate][1];
+		return IIO_VAL_INT_PLUS_MICRO;
 	}
 	return -EINVAL;
 }
 
+static int hmc5843_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct hmc5843_data *data = iio_priv(indio_dev);
+	int ret, rate;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		rate = hmc5843_check_samp_freq(data, val, val2);
+		if (rate < 0)
+			return -EINVAL;
+
+		mutex_lock(&data->lock);
+		ret = hmc5843_set_rate(data, rate);
+		if (ret >= 0)
+			data->rate = rate;
+		mutex_unlock(&data->lock);
+
+		return ret;
+	default:
+		return -EINVAL;
+	}
+}
+
 #define HMC5843_CHANNEL(axis, addr)					\
 	{								\
 		.type = IIO_MAGN,					\
 		.modified = 1,						\
 		.channel2 = IIO_MOD_##axis,				\
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
-		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
+		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |	\
+			BIT(IIO_CHAN_INFO_SAMP_FREQ),			\
 		.address = addr						\
 	}
 
@@ -566,7 +539,6 @@ static const struct iio_chan_spec hmc5883_channels[] = {
 static struct attribute *hmc5843_attributes[] = {
 	&iio_dev_attr_meas_conf.dev_attr.attr,
 	&iio_dev_attr_operating_mode.dev_attr.attr,
-	&iio_dev_attr_sampling_frequency.dev_attr.attr,
 	&iio_dev_attr_in_magn_range.dev_attr.attr,
 	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 	NULL
@@ -579,21 +551,21 @@ static const struct attribute_group hmc5843_group = {
 static const struct hmc5843_chip_info hmc5843_chip_info_tbl[] = {
 	[HMC5843_ID] = {
 		.channels = hmc5843_channels,
-		.regval_to_sample_freq = hmc5843_regval_to_sample_freq,
+		.regval_to_samp_freq = hmc5843_regval_to_samp_freq,
 		.regval_to_input_field_mga =
 			hmc5843_regval_to_input_field_mga,
 		.regval_to_nanoscale = hmc5843_regval_to_nanoscale,
 	},
 	[HMC5883_ID] = {
 		.channels = hmc5883_channels,
-		.regval_to_sample_freq = hmc5883_regval_to_sample_freq,
+		.regval_to_samp_freq = hmc5883_regval_to_samp_freq,
 		.regval_to_input_field_mga =
 			hmc5883_regval_to_input_field_mga,
 		.regval_to_nanoscale = hmc5883_regval_to_nanoscale,
 	},
 	[HMC5883L_ID] = {
 		.channels = hmc5883_channels,
-		.regval_to_sample_freq = hmc5883_regval_to_sample_freq,
+		.regval_to_samp_freq = hmc5883_regval_to_samp_freq,
 		.regval_to_input_field_mga =
 			hmc5883l_regval_to_input_field_mga,
 		.regval_to_nanoscale = hmc5883l_regval_to_nanoscale,
@@ -612,6 +584,7 @@ static void hmc5843_init(struct hmc5843_data *data)
 static const struct iio_info hmc5843_info = {
 	.attrs = &hmc5843_group,
 	.read_raw = &hmc5843_read_raw,
+	.write_raw = &hmc5843_write_raw,
 	.driver_module = THIS_MODULE,
 };