[v3] iio: light: veml6030: add support for triggered buffer

Commit Message

Javier Carrasco Nov. 24, 2024, 6:59 p.m. UTC

All devices supported by this driver (currently veml6030, veml6035
and veml7700) have two 16-bit channels, and can profit for the same
configuration to support data access via triggered buffers.

The measurements are stored in two 16-bit consecutive registers
(addresses 0x04 and 0x05) as little endian, unsigned data.

Signed-off-by: Javier Carrasco <[e-mail]>
---
Changes in v3:
- Ensure that the holes in the scan struct are initialized to zero.
- Link to v2: https://lore.kernel.org/r/[e-mail]

Changes in v2:
- Use u16 instead of __le16 for the channels.
- Move scan struct from data to trigger_handler.
- Drop avail_scan_masks.
- Fix scan_type (IIO_CPU instead of IIO_LE, drop shift = 0).
- Link to v1: https://lore.kernel.org/r/[e-mail]
---
 drivers/iio/light/Kconfig    |  2 ++
 drivers/iio/light/veml6030.c | 76 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 78 insertions(+)


---
base-commit: ab376e4d674037f45d5758c1dc391bd4e11c5dc4
change-id: 20241106-veml6030_triggered_buffer-a38886ca4cce

Best regards,

Patch

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index 29ffa8491927..0e2566ff5f7b 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -683,6 +683,8 @@  config VEML3235
 config VEML6030
 	tristate "VEML6030 and VEML6035 ambient light sensors"
 	select REGMAP_I2C
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
 	depends on I2C
 	help
 	  Say Y here if you want to build a driver for the Vishay VEML6030
diff --git a/drivers/iio/light/veml6030.c b/drivers/iio/light/veml6030.c
index ccb43dfd5cf7..9b71825eea9b 100644
--- a/drivers/iio/light/veml6030.c
+++ b/drivers/iio/light/veml6030.c
@@ -28,6 +28,8 @@ 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 #include <linux/iio/events.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
 
 /* Device registers */
 #define VEML6030_REG_ALS_CONF   0x00
@@ -37,6 +39,7 @@ 
 #define VEML6030_REG_ALS_DATA   0x04
 #define VEML6030_REG_WH_DATA    0x05
 #define VEML6030_REG_ALS_INT    0x06
+#define VEML6030_REG_DATA(ch)   (VEML6030_REG_ALS_DATA + (ch))
 
 /* Bit masks for specific functionality */
 #define VEML6030_ALS_IT       GENMASK(9, 6)
@@ -56,6 +59,12 @@ 
 #define VEML6035_INT_CHAN     BIT(3)
 #define VEML6035_CHAN_EN      BIT(2)
 
+enum veml6030_scan {
+	VEML6030_SCAN_ALS,
+	VEML6030_SCAN_WH,
+	VEML6030_SCAN_TIMESTAMP,
+};
+
 struct veml603x_chip {
 	const char *name;
 	const int(*scale_vals)[][2];
@@ -242,6 +251,13 @@  static const struct iio_chan_spec veml6030_channels[] = {
 						     BIT(IIO_CHAN_INFO_SCALE),
 		.event_spec = veml6030_event_spec,
 		.num_event_specs = ARRAY_SIZE(veml6030_event_spec),
+		.scan_index = VEML6030_SCAN_ALS,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_CPU,
+		},
 	},
 	{
 		.type = IIO_INTENSITY,
@@ -253,7 +269,15 @@  static const struct iio_chan_spec veml6030_channels[] = {
 				BIT(IIO_CHAN_INFO_SCALE),
 		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) |
 						     BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = VEML6030_SCAN_WH,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_CPU,
+		},
 	},
+	IIO_CHAN_SOFT_TIMESTAMP(VEML6030_SCAN_TIMESTAMP),
 };
 
 static const struct iio_chan_spec veml7700_channels[] = {
@@ -266,6 +290,13 @@  static const struct iio_chan_spec veml7700_channels[] = {
 				BIT(IIO_CHAN_INFO_SCALE),
 		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) |
 						     BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = VEML6030_SCAN_ALS,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_CPU,
+		},
 	},
 	{
 		.type = IIO_INTENSITY,
@@ -277,7 +308,15 @@  static const struct iio_chan_spec veml7700_channels[] = {
 				BIT(IIO_CHAN_INFO_SCALE),
 		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) |
 						     BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = VEML6030_SCAN_WH,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_CPU,
+		},
 	},
+	IIO_CHAN_SOFT_TIMESTAMP(VEML6030_SCAN_TIMESTAMP),
 };
 
 static const struct regmap_config veml6030_regmap_config = {
@@ -889,6 +928,37 @@  static irqreturn_t veml6030_event_handler(int irq, void *private)
 	return IRQ_HANDLED;
 }
 
+static irqreturn_t veml6030_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *iio = pf->indio_dev;
+	struct veml6030_data *data = iio_priv(iio);
+	unsigned int reg;
+	int ch, ret, i = 0;
+	struct {
+		u16 chans[2];
+		aligned_s64 timestamp;
+	} scan;
+
+	memset(&scan, 0, sizeof(scan));
+
+	iio_for_each_active_channel(iio, ch) {
+		ret = regmap_read(data->regmap, VEML6030_REG_DATA(ch),
+				  &reg);
+		if (ret)
+			goto done;
+
+		scan.chans[i++] = reg;
+	}
+
+	iio_push_to_buffers_with_timestamp(iio, &scan, pf->timestamp);
+
+done:
+	iio_trigger_notify_done(iio->trig);
+
+	return IRQ_HANDLED;
+}
+
 static int veml6030_set_info(struct iio_dev *indio_dev)
 {
 	struct veml6030_data *data = iio_priv(indio_dev);
@@ -1077,6 +1147,12 @@  static int veml6030_probe(struct i2c_client *client)
 	if (ret < 0)
 		return ret;
 
+	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
+					      veml6030_trigger_handler, NULL);
+	if (ret)
+		return dev_err_probe(&client->dev, ret,
+				     "Failed to register triggered buffer");
+
 	return devm_iio_device_register(&client->dev, indio_dev);
 }