staging: iio: tsl2583: convert to use iio_chan_spec and {read,write}_raw

The tsl2583 driver directly creates sysfs attributes that should instead
be created by the IIO core on behalf of the driver. This patch adds the
iio_chan_spec array, the relevant info_mask elements and the read_raw()
and write_raw() functions to take advantage of features provided by the
IIO core. These sysfs attributes were migrated with this patch:
illuminance0_input, illuminance0_calibbias,
illuminance0_integration_time. This also exposes the raw values read
from the two channels on the sensor.

With this change, these four sysfs entries have their prefix changed
from illuminance0_ to in_illuminance_. This is deemed to be acceptable
since none of the IIO light drivers in mainline use the illuminance0_
prefix, however 8 of the IIO light drivers in mainline use the
in_illuminance_ prefix.

Also fix the units of integration_time to meet with the ABI.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/staging/iio/light/tsl2583.c

@@ -211,28 +211,23 @@ static int taos_get_lux(struct iio_dev *indio_dev)
 	u32 ch0lux = 0;
 	u32 ch1lux = 0;
 
-	if (mutex_trylock(&chip->als_mutex) == 0) {
-		dev_info(&chip->client->dev, "taos_get_lux device is busy\n");
-		return chip->als_cur_info.lux; /* busy, so return LAST VALUE */
-	}
-
 	if (chip->taos_chip_status != TSL258X_CHIP_WORKING) {
 		/* device is not enabled */
 		dev_err(&chip->client->dev, "taos_get_lux device is not enabled\n");
 		ret = -EBUSY;
-		goto out_unlock;
+		goto done;
 	}
 
 	ret = taos_i2c_read(chip->client, (TSL258X_CMD_REG), &buf[0], 1);
 	if (ret < 0) {
 		dev_err(&chip->client->dev, "taos_get_lux failed to read CMD_REG\n");
-		goto out_unlock;
+		goto done;
 	}
 	/* is data new & valid */
 	if (!(buf[0] & TSL258X_STA_ADC_INTR)) {
 		dev_err(&chip->client->dev, "taos_get_lux data not valid\n");
 		ret = chip->als_cur_info.lux; /* return LAST VALUE */
-		goto out_unlock;
+		goto done;
 	}
 
 	for (i = 0; i < 4; i++) {
@@ -243,7 +238,7 @@ static int taos_get_lux(struct iio_dev *indio_dev)
 			dev_err(&chip->client->dev,
 				"taos_get_lux failed to read register %x\n",
 				reg);
-			goto out_unlock;
+			goto done;
 		}
 	}
 
@@ -259,7 +254,7 @@ static int taos_get_lux(struct iio_dev *indio_dev)
 		dev_err(&chip->client->dev,
 			"taos_i2c_write_command failed in taos_get_lux, err = %d\n",
 			ret);
-		goto out_unlock; /* have no data, so return failure */
+		goto done; /* have no data, so return failure */
 	}
 
 	/* extract ALS/lux data */
@@ -276,7 +271,7 @@ static int taos_get_lux(struct iio_dev *indio_dev)
 		/* have no data, so return LAST VALUE */
 		ret = 0;
 		chip->als_cur_info.lux = 0;
-		goto out_unlock;
+		goto done;
 	}
 	/* calculate ratio */
 	ratio = (ch1 << 15) / ch0;
@@ -302,7 +297,7 @@ static int taos_get_lux(struct iio_dev *indio_dev)
 		dev_dbg(&chip->client->dev, "No Data - Return last value\n");
 		ret = 0;
 		chip->als_cur_info.lux = 0;
-		goto out_unlock;
+		goto done;
 	}
 
 	/* adjust for active time scale */
@@ -334,8 +329,7 @@ static int taos_get_lux(struct iio_dev *indio_dev)
 	chip->als_cur_info.lux = lux;
 	ret = lux;
 
-out_unlock:
-	mutex_unlock(&chip->als_mutex);
+done:
 	return ret;
 }
 
@@ -575,69 +569,12 @@ static ssize_t taos_gain_available_show(struct device *dev,
 	return sprintf(buf, "%s\n", "1 8 16 111");
 }
 
-static ssize_t taos_als_time_show(struct device *dev,
-				  struct device_attribute *attr, char *buf)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct tsl2583_chip *chip = iio_priv(indio_dev);
-
-	return sprintf(buf, "%d\n", chip->taos_settings.als_time);
-}
-
-static ssize_t taos_als_time_store(struct device *dev,
-				   struct device_attribute *attr,
-				   const char *buf, size_t len)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct tsl2583_chip *chip = iio_priv(indio_dev);
-	int value;
-
-	if (kstrtoint(buf, 0, &value))
-		return -EINVAL;
-
-	if ((value < 50) || (value > 650))
-		return -EINVAL;
-
-	if (value % 50)
-		return -EINVAL;
-
-	chip->taos_settings.als_time = value;
-
-	return len;
-}
-
 static ssize_t taos_als_time_available_show(struct device *dev,
 					    struct device_attribute *attr,
 					    char *buf)
 {
 	return sprintf(buf, "%s\n",
-		"50 100 150 200 250 300 350 400 450 500 550 600 650");
-}
-
-static ssize_t taos_als_trim_show(struct device *dev,
-				  struct device_attribute *attr, char *buf)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct tsl2583_chip *chip = iio_priv(indio_dev);
-
-	return sprintf(buf, "%d\n", chip->taos_settings.als_gain_trim);
-}
-
-static ssize_t taos_als_trim_store(struct device *dev,
-				   struct device_attribute *attr,
-				   const char *buf, size_t len)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct tsl2583_chip *chip = iio_priv(indio_dev);
-	int value;
-
-	if (kstrtoint(buf, 0, &value))
-		return -EINVAL;
-
-	if (value)
-		chip->taos_settings.als_gain_trim = value;
-
-	return len;
+		"0.000050 0.000100 0.000150 0.000200 0.000250 0.000300 0.000350 0.000400 0.000450 0.000500 0.000550 0.000600 0.000650");
 }
 
 static ssize_t taos_als_cal_target_show(struct device *dev,
@@ -667,18 +604,6 @@ static ssize_t taos_als_cal_target_store(struct device *dev,
 	return len;
 }
 
-static ssize_t taos_lux_show(struct device *dev, struct device_attribute *attr,
-			     char *buf)
-{
-	int ret;
-
-	ret = taos_get_lux(dev_to_iio_dev(dev));
-	if (ret < 0)
-		return ret;
-
-	return sprintf(buf, "%d\n", ret);
-}
-
 static ssize_t taos_do_calibrate(struct device *dev,
 				 struct device_attribute *attr,
 				 const char *buf, size_t len)
@@ -771,18 +696,12 @@ static DEVICE_ATTR(illuminance0_calibscale, S_IRUGO | S_IWUSR,
 static DEVICE_ATTR(illuminance0_calibscale_available, S_IRUGO,
 		taos_gain_available_show, NULL);
 
-static DEVICE_ATTR(illuminance0_integration_time, S_IRUGO | S_IWUSR,
-		taos_als_time_show, taos_als_time_store);
 static DEVICE_ATTR(illuminance0_integration_time_available, S_IRUGO,
 		taos_als_time_available_show, NULL);
 
-static DEVICE_ATTR(illuminance0_calibbias, S_IRUGO | S_IWUSR,
-		taos_als_trim_show, taos_als_trim_store);
-
 static DEVICE_ATTR(illuminance0_input_target, S_IRUGO | S_IWUSR,
 		taos_als_cal_target_show, taos_als_cal_target_store);
 
-static DEVICE_ATTR(illuminance0_input, S_IRUGO, taos_lux_show, NULL);
 static DEVICE_ATTR(illuminance0_calibrate, S_IWUSR, NULL, taos_do_calibrate);
 static DEVICE_ATTR(illuminance0_lux_table, S_IRUGO | S_IWUSR,
 		taos_luxtable_show, taos_luxtable_store);
@@ -790,11 +709,8 @@ static DEVICE_ATTR(illuminance0_lux_table, S_IRUGO | S_IWUSR,
 static struct attribute *sysfs_attrs_ctrl[] = {
 	&dev_attr_illuminance0_calibscale.attr,			/* Gain  */
 	&dev_attr_illuminance0_calibscale_available.attr,
-	&dev_attr_illuminance0_integration_time.attr,	/* I time*/
 	&dev_attr_illuminance0_integration_time_available.attr,
-	&dev_attr_illuminance0_calibbias.attr,			/* trim  */
 	&dev_attr_illuminance0_input_target.attr,
-	&dev_attr_illuminance0_input.attr,
 	&dev_attr_illuminance0_calibrate.attr,
 	&dev_attr_illuminance0_lux_table.attr,
 	NULL
@@ -810,9 +726,141 @@ static int taos_tsl258x_device(unsigned char *bufp)
 	return ((bufp[TSL258X_CHIPID] & 0xf0) == 0x90);
 }
 
+static const struct iio_chan_spec tsl2583_channels[] = {
+	{
+		.type = IIO_LIGHT,
+		.modified = 1,
+		.channel2 = IIO_MOD_LIGHT_IR,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+	},
+	{
+		.type = IIO_LIGHT,
+		.modified = 1,
+		.channel2 = IIO_MOD_LIGHT_BOTH,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+	},
+	{
+		.type = IIO_LIGHT,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+				      BIT(IIO_CHAN_INFO_CALIBBIAS) |
+				      BIT(IIO_CHAN_INFO_INT_TIME),
+	},
+};
+
+static int tsl2583_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int *val, int *val2, long mask)
+{
+	struct tsl2583_chip *chip = iio_priv(indio_dev);
+	int ret = -EINVAL;
+
+	mutex_lock(&chip->als_mutex);
+
+	if (chip->taos_chip_status != TSL258X_CHIP_WORKING) {
+		ret = -EBUSY;
+		goto read_done;
+	}
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (chan->type == IIO_LIGHT) {
+			ret = taos_get_lux(indio_dev);
+			if (ret < 0)
+				goto read_done;
+
+			/*
+			 * From page 20 of the TSL2581, TSL2583 data
+			 * sheet (TAOS134 − MARCH 2011):
+			 *
+			 * One of the photodiodes (channel 0) is
+			 * sensitive to both visible and infrared light,
+			 * while the second photodiode (channel 1) is
+			 * sensitive primarily to infrared light.
+			 */
+			if (chan->channel2 == IIO_MOD_LIGHT_BOTH)
+				*val = chip->als_cur_info.als_ch0;
+			else
+				*val = chip->als_cur_info.als_ch1;
+
+			ret = IIO_VAL_INT;
+		}
+		break;
+	case IIO_CHAN_INFO_PROCESSED:
+		if (chan->type == IIO_LIGHT) {
+			ret = taos_get_lux(indio_dev);
+			if (ret < 0)
+				goto read_done;
+
+			*val = ret;
+			ret = IIO_VAL_INT;
+		}
+		break;
+	case IIO_CHAN_INFO_CALIBBIAS:
+		if (chan->type == IIO_LIGHT) {
+			*val = chip->taos_settings.als_gain_trim;
+			ret = IIO_VAL_INT;
+		}
+		break;
+	case IIO_CHAN_INFO_INT_TIME:
+		if (chan->type == IIO_LIGHT) {
+			*val = 0;
+			*val2 = chip->taos_settings.als_time;
+			ret = IIO_VAL_INT_PLUS_MICRO;
+		}
+		break;
+	default:
+		break;
+	}
+
+read_done:
+	mutex_unlock(&chip->als_mutex);
+
+	return ret;
+}
+
+static int tsl2583_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,
+			     int val, int val2, long mask)
+{
+	struct tsl2583_chip *chip = iio_priv(indio_dev);
+	int ret = -EINVAL;
+
+	mutex_lock(&chip->als_mutex);
+
+	if (chip->taos_chip_status != TSL258X_CHIP_WORKING) {
+		ret = -EBUSY;
+		goto write_done;
+	}
+
+	switch (mask) {
+	case IIO_CHAN_INFO_CALIBBIAS:
+		if (chan->type == IIO_LIGHT) {
+			chip->taos_settings.als_gain_trim = val;
+			ret = 0;
+		}
+		break;
+	case IIO_CHAN_INFO_INT_TIME:
+		if (chan->type == IIO_LIGHT && !val && val2 >= 50 &&
+		    val2 <= 650 && !(val2 % 50)) {
+			chip->taos_settings.als_time = val2;
+			ret = 0;
+		}
+		break;
+	default:
+		break;
+	}
+
+write_done:
+	mutex_unlock(&chip->als_mutex);
+
+	return ret;
+}
+
 static const struct iio_info tsl2583_info = {
 	.attrs = &tsl2583_attribute_group,
 	.driver_module = THIS_MODULE,
+	.read_raw = tsl2583_read_raw,
+	.write_raw = tsl2583_write_raw,
 };
 
 /*
@@ -878,6 +926,8 @@ static int taos_probe(struct i2c_client *clientp,
 	}
 
 	indio_dev->info = &tsl2583_info;
+	indio_dev->channels = tsl2583_channels;
+	indio_dev->num_channels = ARRAY_SIZE(tsl2583_channels);
 	indio_dev->dev.parent = &clientp->dev;
 	indio_dev->modes = INDIO_DIRECT_MODE;
 	indio_dev->name = chip->client->name;