[PATCH v2 0/2] Continuous mode support for VL53l0x

[PATCH v2 0/2] Continuous mode support for VL53l0x

[Abhash Jha]

Hello,

The first patch adds support for checking the sensor ID by reading
MODEL_IDENTIFICATION register and seeing if it returns the value 0xEE

The second patch adds support for continuous mode in the sensor by using
buffers. We enable the sensor's continuous mode in the buffer_postenable
function.
Replaced the irq handler with a threaded irq handler in order to perform
I2C reads for the data. The continuous mode can be disabled by disabling
the buffer.
Added a trigger to the device for the continuous mode. Also validating that
the device uses the internal trigger provided by us.

Changes in v2:
- Added a trigger for the device
- Added a poll function for the triggered buffer setup
- Performed the data reading and pushing to buffers in the poll function
- Minor code refactoring

- Link to v1: https://lore.kernel.org/linux-iio/20240830201627.298264-1-abhashkumarjha123@gmail.com/T/#t

Regards,
Abhash


Abhash Jha (2):
  iio: proximity: vl53l0x-i2c: Added sensor ID check
  iio: proximity: vl53l0x-i2c: Added continuous mode support

 drivers/iio/proximity/vl53l0x-i2c.c | 175 +++++++++++++++++++++++-----
 1 file changed, 148 insertions(+), 27 deletions(-)

-- 
2.43.0

[PATCH v2 1/2] iio: proximity: vl53l0x-i2c: Added sensor ID check

[Abhash Jha]

The commit adds a check for the sensor's model ID. We read the model
identification register (0xC0) and expect a value of 0xEE.

Signed-off-by: Abhash Jha <abhashkumarjha123@gmail.com>
---
 drivers/iio/proximity/vl53l0x-i2c.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/proximity/vl53l0x-i2c.c b/drivers/iio/proximity/vl53l0x-i2c.c
index 8d4f3f849..31d6aeb95 100644
--- a/drivers/iio/proximity/vl53l0x-i2c.c
+++ b/drivers/iio/proximity/vl53l0x-i2c.c
@@ -39,8 +39,11 @@
 
 #define VL_REG_RESULT_INT_STATUS			0x13
 #define VL_REG_RESULT_RANGE_STATUS			0x14
+#define VL_REG_IDENTIFICATION_MODEL_ID			0xC0
 #define VL_REG_RESULT_RANGE_STATUS_COMPLETE		BIT(0)
 
+#define VL53L0X_MODEL_ID_VAL				0xEE
+
 struct vl53l0x_data {
 	struct i2c_client *client;
 	struct completion completion;
@@ -223,6 +226,7 @@ static int vl53l0x_probe(struct i2c_client *client)
 	struct vl53l0x_data *data;
 	struct iio_dev *indio_dev;
 	int error;
+	int ret;
 
 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 	if (!indio_dev)
@@ -237,6 +241,13 @@ static int vl53l0x_probe(struct i2c_client *client)
 				     I2C_FUNC_SMBUS_BYTE_DATA))
 		return -EOPNOTSUPP;
 
+	ret = i2c_smbus_read_byte_data(data->client, VL_REG_IDENTIFICATION_MODEL_ID);
+	if (ret < 0)
+		return -EINVAL;
+
+	if (ret != VL53L0X_MODEL_ID_VAL)
+		dev_info(&client->dev, "Received invalid model id: 0x%x", ret);
+
 	data->vdd_supply = devm_regulator_get(&client->dev, "vdd");
 	if (IS_ERR(data->vdd_supply))
 		return dev_err_probe(&client->dev, PTR_ERR(data->vdd_supply),
@@ -265,8 +276,6 @@ static int vl53l0x_probe(struct i2c_client *client)
 
 	/* usage of interrupt is optional */
 	if (client->irq) {
-		int ret;
-
 		init_completion(&data->completion);
 
 		ret = vl53l0x_configure_irq(client, indio_dev);
-- 
2.43.0

[PATCH v2 2/2] iio: proximity: vl53l0x-i2c: Added continuous mode support

[Abhash Jha]

The continuous mode of the sensor is enabled in the buffer_postenable.
Replaced the original irq handler with a threaded irq handler to perform
i2c reads during continuous mode.
The continuous mode is disabled by disabling the buffer.
Added a trigger for this device to be used for continuous mode.

Signed-off-by: Abhash Jha <abhashkumarjha123@gmail.com>
---
 drivers/iio/proximity/vl53l0x-i2c.c | 162 +++++++++++++++++++++++-----
 1 file changed, 137 insertions(+), 25 deletions(-)

diff --git a/drivers/iio/proximity/vl53l0x-i2c.c b/drivers/iio/proximity/vl53l0x-i2c.c
index 31d6aeb95..26183c352 100644
--- a/drivers/iio/proximity/vl53l0x-i2c.c
+++ b/drivers/iio/proximity/vl53l0x-i2c.c
@@ -22,6 +22,10 @@
 #include <linux/module.h>
 
 #include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
 
 #define VL_REG_SYSRANGE_START				0x00
 
@@ -49,14 +53,75 @@ struct vl53l0x_data {
 	struct completion completion;
 	struct regulator *vdd_supply;
 	struct gpio_desc *reset_gpio;
+	struct iio_trigger *trig;
+
+	struct {
+		u16 chan;
+		s64 timestamp __aligned(8);
+	} scan;
 };
 
-static irqreturn_t vl53l0x_handle_irq(int irq, void *priv)
+static int vl53l0x_clear_irq(struct vl53l0x_data *data)
+{
+	struct device *dev = &data->client->dev;
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(data->client,
+					VL_REG_SYSTEM_INTERRUPT_CLEAR, 1);
+	if (ret < 0)
+		dev_err(dev, "failed to clear error irq: %d\n", ret);
+
+	ret = i2c_smbus_write_byte_data(data->client,
+					VL_REG_SYSTEM_INTERRUPT_CLEAR, 0);
+	if (ret < 0)
+		dev_err(dev, "failed to clear range irq: %d\n", ret);
+
+	ret = i2c_smbus_read_byte_data(data->client, VL_REG_RESULT_INT_STATUS);
+	if (ret < 0 || ret & 0x07) {
+		dev_err(dev, "failed to clear irq: %d\n", ret);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static irqreturn_t vl53l0x_trigger_handler(int irq, void *priv)
+{
+	struct iio_poll_func *pf = priv;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct vl53l0x_data *data = iio_priv(indio_dev);
+	u8 buffer[12];
+	int ret;
+
+	ret = i2c_smbus_read_i2c_block_data(data->client,
+					VL_REG_RESULT_RANGE_STATUS,
+					sizeof(buffer), buffer);
+	if (ret < 0)
+		return ret;
+	else if (ret != 12)
+		return -EREMOTEIO;
+
+	data->scan.chan = get_unaligned_be16(&buffer[10]);
+	iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
+					iio_get_time_ns(indio_dev));
+
+	iio_trigger_notify_done(indio_dev->trig);
+	ret = vl53l0x_clear_irq(data);
+	if (ret < 0)
+		return ret;
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t vl53l0x_threaded_irq(int irq, void *priv)
 {
 	struct iio_dev *indio_dev = priv;
 	struct vl53l0x_data *data = iio_priv(indio_dev);
 
-	complete(&data->completion);
+	if (iio_buffer_enabled(indio_dev))
+		iio_trigger_poll_nested(indio_dev->trig);
+	else
+		complete(&data->completion);
 
 	return IRQ_HANDLED;
 }
@@ -71,8 +136,9 @@ static int vl53l0x_configure_irq(struct i2c_client *client,
 	if (!irq_flags)
 		irq_flags = IRQF_TRIGGER_FALLING;
 
-	ret = devm_request_irq(&client->dev, client->irq, vl53l0x_handle_irq,
-			irq_flags, indio_dev->name, indio_dev);
+	ret = devm_request_threaded_irq(&client->dev, client->irq,
+			NULL, vl53l0x_threaded_irq,
+			irq_flags | IRQF_ONESHOT, indio_dev->name, indio_dev);
 	if (ret) {
 		dev_err(&client->dev, "devm_request_irq error: %d\n", ret);
 		return ret;
@@ -87,26 +153,6 @@ static int vl53l0x_configure_irq(struct i2c_client *client,
 	return ret;
 }
 
-static void vl53l0x_clear_irq(struct vl53l0x_data *data)
-{
-	struct device *dev = &data->client->dev;
-	int ret;
-
-	ret = i2c_smbus_write_byte_data(data->client,
-					VL_REG_SYSTEM_INTERRUPT_CLEAR, 1);
-	if (ret < 0)
-		dev_err(dev, "failed to clear error irq: %d\n", ret);
-
-	ret = i2c_smbus_write_byte_data(data->client,
-					VL_REG_SYSTEM_INTERRUPT_CLEAR, 0);
-	if (ret < 0)
-		dev_err(dev, "failed to clear range irq: %d\n", ret);
-
-	ret = i2c_smbus_read_byte_data(data->client, VL_REG_RESULT_INT_STATUS);
-	if (ret < 0 || ret & 0x07)
-		dev_err(dev, "failed to clear irq: %d\n", ret);
-}
-
 static int vl53l0x_read_proximity(struct vl53l0x_data *data,
 				  const struct iio_chan_spec *chan,
 				  int *val)
@@ -128,7 +174,9 @@ static int vl53l0x_read_proximity(struct vl53l0x_data *data,
 		if (time_left == 0)
 			return -ETIMEDOUT;
 
-		vl53l0x_clear_irq(data);
+		ret = vl53l0x_clear_irq(data);
+		if (ret < 0)
+			return ret;
 	} else {
 		do {
 			ret = i2c_smbus_read_byte_data(client,
@@ -163,7 +211,14 @@ static const struct iio_chan_spec vl53l0x_channels[] = {
 		.type = IIO_DISTANCE,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 				      BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = 0,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 12,
+			.storagebits = 16,
+		},
 	},
+	IIO_CHAN_SOFT_TIMESTAMP(32),
 };
 
 static int vl53l0x_read_raw(struct iio_dev *indio_dev,
@@ -221,6 +276,41 @@ static int vl53l0x_power_on(struct vl53l0x_data *data)
 	return 0;
 }
 
+static int vl53l0x_buffer_postenable(struct iio_dev *indio_dev)
+{
+	struct vl53l0x_data *data = iio_priv(indio_dev);
+
+	return i2c_smbus_write_byte_data(data->client, VL_REG_SYSRANGE_START, 0x02);
+}
+
+static int vl53l0x_buffer_postdisable(struct iio_dev *indio_dev)
+{
+	struct vl53l0x_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(data->client, VL_REG_SYSRANGE_START, 0x01);
+	if (ret < 0)
+		return ret;
+
+	/* Let the ongoing reading finish */
+	reinit_completion(&data->completion);
+	wait_for_completion_timeout(&data->completion, HZ/10);
+	vl53l0x_clear_irq(data);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = {
+	.postenable = &vl53l0x_buffer_postenable,
+	.postdisable = &vl53l0x_buffer_postdisable,
+};
+
+static const struct iio_trigger_ops vl53l0x_trigger_ops = {
+	.validate_device = iio_trigger_validate_own_device,
+};
+
 static int vl53l0x_probe(struct i2c_client *client)
 {
 	struct vl53l0x_data *data;
@@ -278,9 +368,31 @@ static int vl53l0x_probe(struct i2c_client *client)
 	if (client->irq) {
 		init_completion(&data->completion);
 
+		data->trig = devm_iio_trigger_alloc(&client->dev, "%s-dev%d",
+						indio_dev->name,
+						iio_device_id(indio_dev));
+		if (!data->trig)
+			return -ENOMEM;
+
+		data->trig->ops = &vl53l0x_trigger_ops;
+		iio_trigger_set_drvdata(data->trig, indio_dev);
+		ret = devm_iio_trigger_register(&client->dev, data->trig);
+		if (ret)
+			return ret;
+
+		indio_dev->trig = iio_trigger_get(data->trig);
+
 		ret = vl53l0x_configure_irq(client, indio_dev);
 		if (ret)
 			return ret;
+
+		ret = devm_iio_triggered_buffer_setup(&client->dev,
+					indio_dev,
+					NULL,
+					&vl53l0x_trigger_handler,
+					&iio_triggered_buffer_setup_ops);
+		if (ret)
+			return ret;
 	}
 
 	return devm_iio_device_register(&client->dev, indio_dev);
-- 
2.43.0

Re: [PATCH v2 2/2] iio: proximity: vl53l0x-i2c: Added continuous mode support

[kernel test robot]

Hi Abhash,

kernel test robot noticed the following build errors:

[auto build test ERROR on jic23-iio/togreg]
[also build test ERROR on linus/master v6.11-rc6 next-20240902]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Abhash-Jha/iio-proximity-vl53l0x-i2c-Added-sensor-ID-check/20240902-204936
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
patch link:    https://lore.kernel.org/r/20240902122557.129013-3-abhashkumarjha123%40gmail.com
patch subject: [PATCH v2 2/2] iio: proximity: vl53l0x-i2c: Added continuous mode support
config: i386-buildonly-randconfig-005-20240903 (https://download.01.org/0day-ci/archive/20240903/202409030909.1CQBnx22-lkp@intel.com/config)
compiler: clang version 18.1.5 (https://github.com/llvm/llvm-project 617a15a9eac96088ae5e9134248d8236e34b91b1)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240903/202409030909.1CQBnx22-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202409030909.1CQBnx22-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/iio/proximity/vl53l0x-i2c.c:104:20: error: call to undeclared function 'get_unaligned_be16'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     104 |         data->scan.chan = get_unaligned_be16(&buffer[10]);
         |                           ^
   1 error generated.


vim +/get_unaligned_be16 +104 drivers/iio/proximity/vl53l0x-i2c.c

    87	
    88	static irqreturn_t vl53l0x_trigger_handler(int irq, void *priv)
    89	{
    90		struct iio_poll_func *pf = priv;
    91		struct iio_dev *indio_dev = pf->indio_dev;
    92		struct vl53l0x_data *data = iio_priv(indio_dev);
    93		u8 buffer[12];
    94		int ret;
    95	
    96		ret = i2c_smbus_read_i2c_block_data(data->client,
    97						VL_REG_RESULT_RANGE_STATUS,
    98						sizeof(buffer), buffer);
    99		if (ret < 0)
   100			return ret;
   101		else if (ret != 12)
   102			return -EREMOTEIO;
   103	
 > 104		data->scan.chan = get_unaligned_be16(&buffer[10]);
   105		iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
   106						iio_get_time_ns(indio_dev));
   107	
   108		iio_trigger_notify_done(indio_dev->trig);
   109		ret = vl53l0x_clear_irq(data);
   110		if (ret < 0)
   111			return ret;
   112	
   113		return IRQ_HANDLED;
   114	}
   115	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v2 2/2] iio: proximity: vl53l0x-i2c: Added continuous mode support

[kernel test robot]

Hi Abhash,

kernel test robot noticed the following build errors:

[auto build test ERROR on jic23-iio/togreg]
[also build test ERROR on linus/master v6.11-rc6 next-20240902]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Abhash-Jha/iio-proximity-vl53l0x-i2c-Added-sensor-ID-check/20240902-204936
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
patch link:    https://lore.kernel.org/r/20240902122557.129013-3-abhashkumarjha123%40gmail.com
patch subject: [PATCH v2 2/2] iio: proximity: vl53l0x-i2c: Added continuous mode support
config: i386-buildonly-randconfig-001-20240903 (https://download.01.org/0day-ci/archive/20240903/202409030911.PnMVrgOb-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240903/202409030911.PnMVrgOb-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202409030911.PnMVrgOb-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/iio/proximity/vl53l0x-i2c.c: In function 'vl53l0x_trigger_handler':
>> drivers/iio/proximity/vl53l0x-i2c.c:104:27: error: implicit declaration of function 'get_unaligned_be16' [-Werror=implicit-function-declaration]
     104 |         data->scan.chan = get_unaligned_be16(&buffer[10]);
         |                           ^~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/get_unaligned_be16 +104 drivers/iio/proximity/vl53l0x-i2c.c

    87	
    88	static irqreturn_t vl53l0x_trigger_handler(int irq, void *priv)
    89	{
    90		struct iio_poll_func *pf = priv;
    91		struct iio_dev *indio_dev = pf->indio_dev;
    92		struct vl53l0x_data *data = iio_priv(indio_dev);
    93		u8 buffer[12];
    94		int ret;
    95	
    96		ret = i2c_smbus_read_i2c_block_data(data->client,
    97						VL_REG_RESULT_RANGE_STATUS,
    98						sizeof(buffer), buffer);
    99		if (ret < 0)
   100			return ret;
   101		else if (ret != 12)
   102			return -EREMOTEIO;
   103	
 > 104		data->scan.chan = get_unaligned_be16(&buffer[10]);
   105		iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
   106						iio_get_time_ns(indio_dev));
   107	
   108		iio_trigger_notify_done(indio_dev->trig);
   109		ret = vl53l0x_clear_irq(data);
   110		if (ret < 0)
   111			return ret;
   112	
   113		return IRQ_HANDLED;
   114	}
   115	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki