[PATCH 2/2] iio: adc: ti-ads1015: use dynamically generated attributes

[Ladislav Michl <ladis@linux-mips.org>]

Generate attributes dynamically based on actual values used
by driver - leads to slightly smaller code (on ARM and X64)
Scale and sampling frequency definitions are at one place now.

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
---
 drivers/iio/adc/ti-ads1015.c | 105 ++++++++++++++++++++++++-------------------
 1 file changed, 60 insertions(+), 45 deletions(-)

diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c
index 86fd2753869d..2795553d5340 100644
--- a/drivers/iio/adc/ti-ads1015.c
+++ b/drivers/iio/adc/ti-ads1015.c
@@ -73,28 +73,30 @@ enum ads1015_channels {
 	ADS1015_TIMESTAMP,
 };
 
-static const unsigned int ads1015_data_rate[] = {
+static const unsigned short ads1015_data_rate[] = {
 	128, 250, 490, 920, 1600, 2400, 3300, 3300
 };
 
-static const unsigned int ads1115_data_rate[] = {
+static const unsigned short ads1115_data_rate[] = {
 	8, 16, 32, 64, 128, 250, 475, 860
 };
 
 static const struct {
-	int scale;
-	int uscale;
+	short scale;
+	short mscale;
 } ads1015_scale[] = {
-	{3, 0},
-	{2, 0},
-	{1, 0},
-	{0, 500000},
-	{0, 250000},
-	{0, 125000},
-	{0, 125000},
-	{0, 125000},
+	{ 3, 0 },
+	{ 2, 0 },
+	{ 1, 0 },
+	{ 0, 500 },
+	{ 0, 250 },
+	{ 0, 125 },
+	{ 0, 125 },
+	{ 0, 125 },
 };
 
+#define ADS1015_SCALES_SIZE	(ARRAY_SIZE(ads1015_scale) - 2)
+
 #define ADS1015_V_CHAN(_chan, _addr) {				\
 	.type = IIO_VOLTAGE,					\
 	.indexed = 1,						\
@@ -182,7 +184,8 @@ struct ads1015_data {
 	struct mutex lock;
 	struct ads1015_channel_data channel_data[ADS1015_CHANNELS];
 
-	unsigned int *data_rate;
+	unsigned short *data_rate;
+	unsigned char data_rate_size;
 };
 
 static bool ads1015_is_writeable_reg(struct device *dev, unsigned int reg)
@@ -303,9 +306,9 @@ static int ads1015_set_scale(struct ads1015_data *data, int chan,
 {
 	int i, ret, rindex = -1;
 
-	for (i = 0; i < ARRAY_SIZE(ads1015_scale); i++)
+	for (i = 0; i < ADS1015_SCALES_SIZE; i++)
 		if (ads1015_scale[i].scale == scale &&
-		    ads1015_scale[i].uscale == uscale) {
+		    ads1015_scale[i].mscale * 1000 == uscale) {
 			rindex = i;
 			break;
 		}
@@ -327,7 +330,7 @@ static int ads1015_set_data_rate(struct ads1015_data *data, int chan, int rate)
 {
 	int i, ret, rindex = -1;
 
-	for (i = 0; i < ARRAY_SIZE(ads1015_data_rate); i++)
+	for (i = 0; i < data->data_rate_size; i++)
 		if (data->data_rate[i] == rate) {
 			rindex = i;
 			break;
@@ -386,7 +389,7 @@ static int ads1015_read_raw(struct iio_dev *indio_dev,
 	case IIO_CHAN_INFO_SCALE:
 		idx = data->channel_data[chan->address].pga;
 		*val = ads1015_scale[idx].scale;
-		*val2 = ads1015_scale[idx].uscale;
+		*val2 = ads1015_scale[idx].mscale * 1000;
 		ret = IIO_VAL_INT_PLUS_MICRO;
 		break;
 	case IIO_CHAN_INFO_SAMP_FREQ:
@@ -446,16 +449,44 @@ static const struct iio_buffer_setup_ops ads1015_buffer_setup_ops = {
 	.validate_scan_mask = &iio_validate_scan_mask_onehot,
 };
 
-static IIO_CONST_ATTR(scale_available, "3 2 1 0.5 0.25 0.125");
+static ssize_t ads1015_show_scales(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	int i;
+	ssize_t l = 0;
+
+	for (i = 0; i < ADS1015_SCALES_SIZE; i++)
+		l += sprintf(buf + l, "%u.%03u%c",
+			ads1015_scale[i].scale, ads1015_scale[i].mscale,
+			i == ADS1015_SCALES_SIZE - 1 ? '\n' : ' ');
+
+	return l;
+}
+
+static ssize_t ads1015_show_sample_rates(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	int i;
+	ssize_t l = 0;
+	struct ads1015_data *data = iio_priv(dev_to_iio_dev(dev));
+
+	for (i = 0; i < data->data_rate_size; i++)
+		l += sprintf(buf + l, "%u%c", data->data_rate[i],
+			i == data->data_rate_size - 1 ? '\n' : ' ');
+
+	return l;
+}
+
+static IIO_DEVICE_ATTR(scale_available, S_IRUGO,
+		       ads1015_show_scales, NULL, 0);
+static IIO_DEVICE_ATTR(sampling_frequency_available, S_IRUGO,
+		       ads1015_show_sample_rates, NULL, 0);
 
-static IIO_CONST_ATTR_NAMED(ads1015_sampling_frequency_available,
-	sampling_frequency_available, "128 250 490 920 1600 2400 3300");
-static IIO_CONST_ATTR_NAMED(ads1115_sampling_frequency_available,
-	sampling_frequency_available, "8 16 32 64 128 250 475 860");
 
 static struct attribute *ads1015_attributes[] = {
-	&iio_const_attr_scale_available.dev_attr.attr,
-	&iio_const_attr_ads1015_sampling_frequency_available.dev_attr.attr,
+	&iio_dev_attr_scale_available.dev_attr.attr,
+	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 	NULL,
 };
 
@@ -463,16 +494,6 @@ static const struct attribute_group ads1015_attribute_group = {
 	.attrs = ads1015_attributes,
 };
 
-static struct attribute *ads1115_attributes[] = {
-	&iio_const_attr_scale_available.dev_attr.attr,
-	&iio_const_attr_ads1115_sampling_frequency_available.dev_attr.attr,
-	NULL,
-};
-
-static const struct attribute_group ads1115_attribute_group = {
-	.attrs = ads1115_attributes,
-};
-
 static const struct iio_info ads1015_info = {
 	.driver_module	= THIS_MODULE,
 	.read_raw	= ads1015_read_raw,
@@ -480,13 +501,6 @@ static const struct iio_info ads1015_info = {
 	.attrs          = &ads1015_attribute_group,
 };
 
-static const struct iio_info ads1115_info = {
-	.driver_module	= THIS_MODULE,
-	.read_raw	= ads1015_read_raw,
-	.write_raw	= ads1015_write_raw,
-	.attrs          = &ads1115_attribute_group,
-};
-
 #ifdef CONFIG_OF
 static int ads1015_get_channels_config_of(struct i2c_client *client)
 {
@@ -594,6 +608,7 @@ static int ads1015_probe(struct i2c_client *client,
 	indio_dev->dev.of_node = client->dev.of_node;
 	indio_dev->name = ADS1015_DRV_NAME;
 	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->info = &ads1015_info;
 
 	if (client->dev.of_node)
 		chip = (enum chip_ids)of_device_get_match_data(&client->dev);
@@ -603,14 +618,14 @@ static int ads1015_probe(struct i2c_client *client,
 	case ADS1015:
 		indio_dev->channels = ads1015_channels;
 		indio_dev->num_channels = ARRAY_SIZE(ads1015_channels);
-		indio_dev->info = &ads1015_info;
-		data->data_rate = (unsigned int *) &ads1015_data_rate;
+		data->data_rate = (unsigned short *) &ads1015_data_rate;
+		data->data_rate_size = ARRAY_SIZE(ads1015_data_rate) - 1;
 		break;
 	case ADS1115:
 		indio_dev->channels = ads1115_channels;
 		indio_dev->num_channels = ARRAY_SIZE(ads1115_channels);
-		indio_dev->info = &ads1115_info;
-		data->data_rate = (unsigned int *) &ads1115_data_rate;
+		data->data_rate = (unsigned short *) &ads1115_data_rate;
+		data->data_rate_size = ARRAY_SIZE(ads1115_data_rate);
 		break;
 	}
 
-- 
2.11.0