[PATCH 4/6] iio: accel: kxcjk-1013: Set adjustable range

[Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>]

This chip can support 3 different ranges. Allowing range specification.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/iio/accel/kxcjk-1013.c | 80 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 79 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/accel/kxcjk-1013.c b/drivers/iio/accel/kxcjk-1013.c
index 4912143..975f8a6 100644
--- a/drivers/iio/accel/kxcjk-1013.c
+++ b/drivers/iio/accel/kxcjk-1013.c
@@ -70,6 +70,10 @@
 #define KXCJK1013_REG_INT_REG1_BIT_IEA	BIT(4)
 #define KXCJK1013_REG_INT_REG1_BIT_IEN	BIT(5)
 
+#define KXCJK1013_RANGE_2G		0x00
+#define KXCJK1013_RANGE_4G		0x01
+#define KXCJK1013_RANGE_8G		0x02
+
 #define KXCJK1013_DATA_MASK_12_BIT	0x0FFF
 #define KXCJK1013_MAX_STARTUP_TIME_US	100000
 
@@ -86,6 +90,7 @@ struct kxcjk1013_data {
 	struct mutex mutex;
 	s16 buffer[8];
 	u8 odr_bits;
+	u8 range;
 	bool active_high_intr;
 	bool trigger_on;
 };
@@ -120,6 +125,14 @@ static const struct {
 			   {0x02, 21000}, {0x03, 11000}, {0x04, 6400},
 			   {0x05, 3900}, {0x06, 2700}, {0x07, 2100} };
 
+static const struct {
+	u16 scale;
+	u8 gsel_0;
+	u8 gsel_1;
+} KXCJK1013_scale_table[] = { {9582, 0, 0},
+			      {19163, 0, 1},
+			      {38326, 1, 0} };
+
 static int kxcjk1013_set_mode(struct kxcjk1013_data *data,
 			      enum kxcjk1013_mode mode)
 {
@@ -190,6 +203,7 @@ static int kxcjk1013_chip_init(struct kxcjk1013_data *data)
 	/* Setting range to 4G */
 	ret |= KXCJK1013_REG_CTRL1_BIT_GSEL0;
 	ret &= ~KXCJK1013_REG_CTRL1_BIT_GSEL1;
+	data->range = KXCJK1013_RANGE_4G;
 
 	/* Set 12 bit mode */
 	ret |= KXCJK1013_REG_CTRL1_BIT_RES;
@@ -422,6 +436,59 @@ static int kxcjk1013_get_startup_times(struct kxcjk1013_data *data)
 	return KXCJK1013_MAX_STARTUP_TIME_US;
 }
 
+static int kxcjk1013_set_scale(struct kxcjk1013_data *data, int val)
+{
+	int ret, i;
+	enum kxcjk1013_mode store_mode;
+
+
+	for (i = 0; i < ARRAY_SIZE(KXCJK1013_scale_table); ++i) {
+		if (KXCJK1013_scale_table[i].scale == val) {
+
+			ret = kxcjk1013_get_mode(data, &store_mode);
+			if (ret < 0)
+				return ret;
+
+			ret = kxcjk1013_set_mode(data, STANDBY);
+			if (ret < 0)
+				return ret;
+
+			ret = i2c_smbus_read_byte_data(data->client,
+						       KXCJK1013_REG_CTRL1);
+			if (ret < 0) {
+				dev_err(&data->client->dev,
+						"Error reading reg_ctrl1\n");
+				return ret;
+			}
+
+			ret |= (KXCJK1013_scale_table[i].gsel_0 << 3);
+			ret |= (KXCJK1013_scale_table[i].gsel_1 << 4);
+
+			ret = i2c_smbus_write_byte_data(data->client,
+							KXCJK1013_REG_CTRL1,
+							ret);
+			if (ret < 0) {
+				dev_err(&data->client->dev,
+					"Error writing reg_ctrl1\n");
+				return ret;
+			}
+
+			data->range = i;
+			dev_dbg(&data->client->dev, "New Scale range %d\n", i);
+
+			if (store_mode == OPERATION) {
+				ret = kxcjk1013_set_mode(data, OPERATION);
+				if (ret)
+					return ret;
+			}
+
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
 static int kxcjk1013_read_raw(struct iio_dev *indio_dev,
 			      struct iio_chan_spec const *chan, int *val,
 			      int *val2, long mask)
@@ -458,7 +525,7 @@ static int kxcjk1013_read_raw(struct iio_dev *indio_dev,
 
 	case IIO_CHAN_INFO_SCALE:
 		*val = 0;
-		*val2 = 19163; /* range +-4g (4/2047*9.806650) */
+		*val2 = KXCJK1013_scale_table[data->range].scale;
 		return IIO_VAL_INT_PLUS_MICRO;
 
 	case IIO_CHAN_INFO_SAMP_FREQ:
@@ -485,6 +552,14 @@ static int kxcjk1013_write_raw(struct iio_dev *indio_dev,
 		ret = kxcjk1013_set_odr(data, val, val2);
 		mutex_unlock(&data->mutex);
 		break;
+	case IIO_CHAN_INFO_SCALE:
+		if (val)
+			return -EINVAL;
+
+		mutex_lock(&data->mutex);
+		ret = kxcjk1013_set_scale(data, val2);
+		mutex_unlock(&data->mutex);
+		break;
 	default:
 		ret = -EINVAL;
 	}
@@ -506,8 +581,11 @@ static int kxcjk1013_validate_trigger(struct iio_dev *indio_dev,
 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
 	"0.781000 1.563000 3.125000 6.250000 12.500000 25 50 100 200 400 800 1600");
 
+static IIO_CONST_ATTR(in_accel_scale_available, "0.009582 0.019163 0.038326");
+
 static struct attribute *kxcjk1013_attributes[] = {
 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
+	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
 	NULL,
 };
 
-- 
1.7.11.7