[PATCH v8 0/2] iio: proximity: add driver for ST VL53L1X ToF sensor

[PATCH v8 0/2] iio: proximity: add driver for ST VL53L1X ToF sensor

[Siratul Islam]

This series adds support for the STMicroelectronics VL53L1X
Time-of-Flight ranging sensor.

The VL53L1X is a ToF laser-ranging sensor with I2C interface,
capable of measuring distances up to 4 meters. The driver
supports both interrupt-driven and polled operation.

Why a separate driver is needed (instead of extending vl53l0x-i2c.c):
The VL53L1X is fundamentally different from the VL53L0X despite the
similar naming. Extending the existing driver would require rewriting
the majority of it.

Key differences include:
- A different register map (16-bit addresses vs. 8-bit addresses).
- Requires a 91-byte firmware configuration blob to be loaded at boot.
- Requires a VHV calibration cycle.
- Has distance mode and timing budget configurations.
- Uses the regmap API rather than raw i2c_smbus calls.

I also reviewed other drivers in drivers/iio/proximity/ and can
confirm this IP block does not appear to be shared by any other
existing driver.

Tested on Raspberry Pi 5 with a VL53L1X breakout board.

Note on vdd-supply:
vdd-supply is required for st,vl53l1x. It is not globally required
for backwards compatibility with existing st,vl53l0x devicetrees
that omit it.

---
Changes in v8:
- Use devm_regulator_get_enable() and devm_reset_control_get_optional_exclusive_deasserted().
- Drop i2c_check_functionality().
- Remove power_on/power_off helpers.
- Require vdd-supply only for st,vl53l1x.


Changes in v7:
- Add VL53L1X_REG_ prefix for register defines.
- Use iio_push_to_buffers_with_ts().
- Use continuous ranging and drop postenable/predisable.
- Add comments for XSHUT reset, default config values.
- Drop vdd-supply description in binding and comment in driver.
- Add ABI rationale for vdd-supply to commit message (per Krzysztof, Jonathan).


Changes in v6:
- Make vdd-supply required. Add descriptions to vdd-supply and reset-gpios (per Jonathan).
- Check reset_control_deassert() return value (per Andy).
- Use volatile table for result registers and caching for the rest. Also mark write-only registers.
- Drop tag from Krzysztof Kozlowski for vdd-supply requirement change.

Changes in v5:
- Patch 1: No changes. Collected Reviewed-by tag from Krzysztof Kozlowski.
- Switch XSHUT pin handling from the GPIO consumer API to the Reset controller API.
- Drop <linux/gpio/consumer.h> and include <linux/reset.h>.


Changes in v4:
- Move i2c_check_functionality() to the top of probe before allocations.
- Use struct u32_fract for oscillator correction math.
- Explicitly set .cache_type = REGCACHE_NONE.
- Document intentional predisable drain
- Use dev_err_probe() for firmware boot timeout and remove duplicate IRQ request error message.
- Use sizeof() in regmap bulk read/writes instead of hardcoded lengths.
- Add missing headers (<linux/math.h>, <linux/time.h>, <asm/byteorder.h>).
- Various formatting cleanups per Andy's review.


Changes in v3:
- Merge DT binding into existing st,vl53l0x.yaml (per Krzysztof).
- Use "reset-gpios" in the binding but xshut_gpio in the driver since that's the actual pin name.
- Replace manual polling loops in chip_init and read_proximity with regmap_read_poll_timeout().
- Remove irq_get_trigger_type() and pass IRQF_NO_THREAD directly (per Andy).
- Drop struct i2c_client from private data and store irq as int instead. Derive struct device from regmap where needed.
- Add dev_err_probe() to first devm_request_irq() error path.
- Replace linux/device.h with linux/dev_printk.h, add linux/array_size.h, linux/err.h, linux/types.h (per Andy).
- Use USEC_PER_MSEC for poll timeouts.
- Remove unnecessary casts.
- Divide long config blob to 8 values per line.
- Rename goto label to notify_and_clear_irq and drop unused dev_dbg.
- Add datasheet section reference for boot delay comment.
- vdd-supply no longer required in shared binding to avoid breaking existing st,vl53l0x devicetrees.


Changes in v2:
- Skip software reset in chip_init when xshut GPIO is available, since the device was already hardware-reset during power-on.
- Rename "reset" GPIO to "xshut" to match the datasheet pin name and updated DT binding accordingly.
- Make vdd-supply required in DT binding.
- Use reg_sequence arrays and regmap_multi_reg_write() for distance mode configuration.
- Switch to a hardirq handler with iio_trigger_poll() and IRQF_NO_THREAD instead of a threaded handler.
- Drop IRQF_TRIGGER_FALLING fallback. Leave trigger type to firmware/DT.
- Use iio_validate_own_trigger() instead of a custom validate_trigger, drop trig pointer from driver data.
- Switch usleep_range() to fsleep() throughout and add comments for sleep values.
- Don't fail probe on unknown model ID, just log with dev_info().
- Split stop_ranging cleanup into its own devm action, separate from power_off.
- Add missing includes: device.h, bitfield.h, completion.h, mod_devicetable.h.
- Use FIELD_GET() for range status checks.
- Move configure_irq() closer to probe(), use dev_err_probe() for its error paths.
- Fix buffer ops symmetry: postdisable -> predisable.
- Drop reg_format_endian from regmap config.
- Various alignment and formatting fixes.

Link to v7: https://lore.kernel.org/linux-iio/20260325063254.18062-1-email@sirat.me
Link to v6: https://lore.kernel.org/linux-iio/20260319190738.151614-1-email@sirat.me
Link to v5: https://lore.kernel.org/linux-iio/20260313113737.151881-1-email@sirat.me
Link to v4: https://lore.kernel.org/linux-iio/20260312183721.40482-1-email@sirat.me
Link to v3: https://lore.kernel.org/linux-iio/20260311224044.21480-1-email@sirat.me
Link to v2: https://lore.kernel.org/linux-iio/20260308113728.40860-1-email@sirat.me
Link to v1: https://lore.kernel.org/linux-iio/20260303090253.42076-1-email@sirat.me

Siratul Islam (2):
  dt-bindings: iio: proximity: add ST VL53L1X ToF sensor
  iio: proximity: add driver for ST VL53L1X ToF sensor

 .../bindings/iio/proximity/st,vl53l0x.yaml    |  24 +-
 MAINTAINERS                                   |   7 +
 drivers/iio/proximity/Kconfig                 |  15 +
 drivers/iio/proximity/Makefile                |   1 +
 drivers/iio/proximity/vl53l1x-i2c.c           | 756 ++++++++++++++++++
 5 files changed, 800 insertions(+), 3 deletions(-)
 create mode 100644 drivers/iio/proximity/vl53l1x-i2c.c

--
2.53.0

[PATCH v8 1/2] dt-bindings: iio: proximity: add ST VL53L1X ToF sensor

[Siratul Islam]

Add device tree binding documentation for the STMicroelectronics
VL53L1X Time-of-Flight ranging sensor connected via I2C.

Signed-off-by: Siratul Islam <email@sirat.me>
---
 .../bindings/iio/proximity/st,vl53l0x.yaml    | 24 ++++++++++++++++---
 MAINTAINERS                                   |  6 +++++
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/iio/proximity/st,vl53l0x.yaml b/Documentation/devicetree/bindings/iio/proximity/st,vl53l0x.yaml
index 322befc41de6..9adb9b13ccc5 100644
--- a/Documentation/devicetree/bindings/iio/proximity/st,vl53l0x.yaml
+++ b/Documentation/devicetree/bindings/iio/proximity/st,vl53l0x.yaml
@@ -4,14 +4,17 @@
 $id: http://devicetree.org/schemas/iio/proximity/st,vl53l0x.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
-title: ST VL53L0X ToF ranging sensor
+title: ST VL53L0X/VL53L1X ToF ranging sensor
 
 maintainers:
   - Song Qiang <songqiang1304521@gmail.com>
+  - Siratul Islam <email@sirat.me>
 
 properties:
   compatible:
-    const: st,vl53l0x
+    enum:
+      - st,vl53l0x
+      - st,vl53l1x
 
   reg:
     maxItems: 1
@@ -21,6 +24,8 @@ properties:
 
   reset-gpios:
     maxItems: 1
+    description:
+      Phandle to the XSHUT GPIO. Used for hardware reset.
 
   vdd-supply: true
 
@@ -28,6 +33,18 @@ required:
   - compatible
   - reg
 
+# vdd-supply is not made globally required to maintain backwards compatibility
+# with existing st,vl53l0x devicetrees that do not specify it.
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: st,vl53l1x
+    then:
+      required:
+        - vdd-supply
+
 additionalProperties: false
 
 examples:
@@ -38,8 +55,9 @@ examples:
         #size-cells = <0>;
 
         proximity@29 {
-            compatible = "st,vl53l0x";
+            compatible = "st,vl53l1x";
             reg = <0x29>;
+            vdd-supply = <&reg_3v3>;
             interrupt-parent = <&gpio>;
             interrupts = <23 IRQ_TYPE_EDGE_FALLING>;
         };
diff --git a/MAINTAINERS b/MAINTAINERS
index 61bf550fd37c..a142a97be4cb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -25093,6 +25093,12 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/iio/proximity/st,vl53l0x.yaml
 F:	drivers/iio/proximity/vl53l0x-i2c.c
 
+ST VL53L1X ToF RANGER(I2C) IIO DRIVER
+M:	Siratul Islam <email@sirat.me>
+L:	linux-iio@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/iio/proximity/st,vl53l0x.yaml
+
 STABLE BRANCH
 M:	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
 M:	Sasha Levin <sashal@kernel.org>
-- 
2.53.0

Re: [PATCH v8 1/2] dt-bindings: iio: proximity: add ST VL53L1X ToF sensor

[Krzysztof Kozlowski]

On Thu, Mar 26, 2026 at 02:19:41AM +0600, Siratul Islam wrote:
>    vdd-supply: true
>  
> @@ -28,6 +33,18 @@ required:
>    - compatible
>    - reg
>  
> +# vdd-supply is not made globally required to maintain backwards compatibility
> +# with existing st,vl53l0x devicetrees that do not specify it.

Commit should rather explain that, not code.

Anyway, regardless:

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof

Re: [PATCH v8 1/2] dt-bindings: iio: proximity: add ST VL53L1X ToF sensor

[Jonathan Cameron]

On Thu, 26 Mar 2026 08:38:59 +0100
Krzysztof Kozlowski <krzk@kernel.org> wrote:

> On Thu, Mar 26, 2026 at 02:19:41AM +0600, Siratul Islam wrote:
> >    vdd-supply: true
> >  
> > @@ -28,6 +33,18 @@ required:
> >    - compatible
> >    - reg
> >  
> > +# vdd-supply is not made globally required to maintain backwards compatibility
> > +# with existing st,vl53l0x devicetrees that do not specify it.  
> 
> Commit should rather explain that, not code.
That was my suggestion. I'm not that tied to it though so moved to the commit message.
> 
> Anyway, regardless:
> 
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Thanks,

J
> 
> Best regards,
> Krzysztof
> 

[PATCH v8 2/2] iio: proximity: add driver for ST VL53L1X ToF sensor

[Siratul Islam]

Add support for the STMicroelectronics VL53L1X Time-of-Flight
ranging sensor with I2C interface.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Siratul Islam <email@sirat.me>
---
 MAINTAINERS                         |   1 +
 drivers/iio/proximity/Kconfig       |  15 +
 drivers/iio/proximity/Makefile      |   1 +
 drivers/iio/proximity/vl53l1x-i2c.c | 756 ++++++++++++++++++++++++++++
 4 files changed, 773 insertions(+)
 create mode 100644 drivers/iio/proximity/vl53l1x-i2c.c

diff --git a/MAINTAINERS b/MAINTAINERS
index a142a97be4cb..50531a87bf2e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -25098,6 +25098,7 @@ M:	Siratul Islam <email@sirat.me>
 L:	linux-iio@vger.kernel.org
 S:	Maintained
 F:	Documentation/devicetree/bindings/iio/proximity/st,vl53l0x.yaml
+F:	drivers/iio/proximity/vl53l1x-i2c.c
 
 STABLE BRANCH
 M:	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/iio/proximity/Kconfig b/drivers/iio/proximity/Kconfig
index 6070974c2c85..bb77fad2a1b3 100644
--- a/drivers/iio/proximity/Kconfig
+++ b/drivers/iio/proximity/Kconfig
@@ -244,6 +244,21 @@ config VL53L0X_I2C
 	  To compile this driver as a module, choose M here: the
 	  module will be called vl53l0x-i2c.
 
+config VL53L1X_I2C
+	tristate "STMicroelectronics VL53L1X ToF ranger sensor (I2C)"
+	depends on I2C
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	select REGMAP_I2C
+	select RESET_CONTROLLER
+	help
+	  Say Y here to build a driver for STMicroelectronics VL53L1X
+	  ToF ranger sensors with i2c interface.
+	  This driver can be used to measure the distance of objects.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called vl53l1x-i2c.
+
 config AW96103
 	tristate "AW96103/AW96105 Awinic proximity sensor"
 	select REGMAP_I2C
diff --git a/drivers/iio/proximity/Makefile b/drivers/iio/proximity/Makefile
index 152034d38c49..4352833dd8a4 100644
--- a/drivers/iio/proximity/Makefile
+++ b/drivers/iio/proximity/Makefile
@@ -23,5 +23,6 @@ obj-$(CONFIG_SX_COMMON) 	+= sx_common.o
 obj-$(CONFIG_SX9500)		+= sx9500.o
 obj-$(CONFIG_VCNL3020)		+= vcnl3020.o
 obj-$(CONFIG_VL53L0X_I2C)	+= vl53l0x-i2c.o
+obj-$(CONFIG_VL53L1X_I2C)	+= vl53l1x-i2c.o
 obj-$(CONFIG_AW96103)		+= aw96103.o
 
diff --git a/drivers/iio/proximity/vl53l1x-i2c.c b/drivers/iio/proximity/vl53l1x-i2c.c
new file mode 100644
index 000000000000..4d9cb3983dba
--- /dev/null
+++ b/drivers/iio/proximity/vl53l1x-i2c.c
@@ -0,0 +1,756 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause
+/*
+ * Support for ST VL53L1X FlightSense ToF Ranging Sensor on a i2c bus.
+ *
+ * Copyright (C) 2026 Siratul Islam <email@sirat.me>
+ *
+ * Datasheet available at
+ * <https://www.st.com/resource/en/datasheet/vl53l1x.pdf>
+ *
+ * Default 7-bit i2c slave address 0x29.
+ *
+ * The VL53L1X requires a firmware configuration blob to be loaded at boot.
+ * Register values for the default configuration are taken from
+ * ST's VL53L1X Ultra Lite Driver (STSW-IMG009).
+ */
+
+#include <linux/array_size.h>
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/dev_printk.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/math.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/reset.h>
+#include <linux/time.h>
+#include <linux/types.h>
+
+#include <asm/byteorder.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define VL53L1X_REG_SOFT_RESET						0x0000
+#define VL53L1X_REG_VHV_CONFIG__TIMEOUT_MACROP_LOOP_BOUND		0x0008
+#define VL53L1X_REG_VHV_CONFIG__INIT					0x000B
+#define VL53L1X_REG_GPIO_HV_MUX__CTRL					0x0030
+#define VL53L1X_REG_GPIO__TIO_HV_STATUS					0x0031
+#define VL53L1X_REG_SYSTEM__INTERRUPT_CONFIG_GPIO			0x0046
+#define VL53L1X_REG_PHASECAL_CONFIG__TIMEOUT_MACROP			0x004B
+#define VL53L1X_REG_RANGE_CONFIG__TIMEOUT_MACROP_A			0x005E
+#define VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_A			0x0060
+#define VL53L1X_REG_RANGE_CONFIG__TIMEOUT_MACROP_B			0x0061
+#define VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_B			0x0063
+#define VL53L1X_REG_RANGE_CONFIG__VALID_PHASE_HIGH			0x0069
+#define VL53L1X_REG_SYSTEM__INTERMEASUREMENT_PERIOD			0x006C
+#define VL53L1X_REG_SD_CONFIG__WOI_SD0					0x0078
+#define VL53L1X_REG_SD_CONFIG__WOI_SD1					0x0079
+#define VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD0			0x007A
+#define VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD1			0x007B
+#define VL53L1X_REG_SYSTEM__INTERRUPT_CLEAR				0x0086
+#define VL53L1X_REG_SYSTEM__MODE_START					0x0087
+#define VL53L1X_REG_RESULT__RANGE_STATUS				0x0089
+#define VL53L1X_REG_RESULT__FINAL_CROSSTALK_CORRECTED_RANGE_MM_SD0	0x0096
+#define VL53L1X_REG_RESULT__OSC_CALIBRATE_VAL				0x00DE
+#define VL53L1X_REG_FIRMWARE__SYSTEM_STATUS				0x00E5
+#define VL53L1X_REG_IDENTIFICATION__MODEL_ID				0x010F
+#define VL53L1X_REG_DEFAULT_CONFIG					0x002D
+
+#define VL53L1X_MODEL_ID_VAL		0xEACC
+
+#define VL53L1X_MODE_START_TIMED	0x40
+#define VL53L1X_MODE_START_STOP		0x00
+
+#define VL53L1X_INT_NEW_SAMPLE_READY	0x02
+
+#define VL53L1X_GPIO_HV_MUX_POLARITY	BIT(4)
+
+#define VL53L1X_VHV_LOOP_BOUND_TWO	0x09
+
+#define VL53L1X_RANGE_STATUS_MASK	GENMASK(4, 0)
+#define VL53L1X_RANGE_STATUS_VALID	9
+
+#define VL53L1X_OSC_CALIBRATE_MASK	GENMASK(9, 0)
+
+/* Inter-measurement period uses PLL divider with 1.075 oscillator correction */
+static const struct u32_fract vl53l1x_osc_correction = {
+	.numerator = 1075,
+	.denominator = 1000,
+};
+
+enum vl53l1x_distance_mode {
+	VL53L1X_SHORT,
+	VL53L1X_LONG,
+};
+
+struct vl53l1x_data {
+	struct regmap *regmap;
+	struct completion completion;
+	struct reset_control *xshut_reset;
+	enum vl53l1x_distance_mode distance_mode;
+	u8 gpio_polarity;
+	int irq;
+};
+
+static const struct regmap_range vl53l1x_volatile_ranges[] = {
+	regmap_reg_range(VL53L1X_REG_GPIO__TIO_HV_STATUS,
+			 VL53L1X_REG_GPIO__TIO_HV_STATUS),
+	regmap_reg_range(VL53L1X_REG_RESULT__RANGE_STATUS,
+			 VL53L1X_REG_RESULT__RANGE_STATUS),
+	regmap_reg_range(VL53L1X_REG_RESULT__FINAL_CROSSTALK_CORRECTED_RANGE_MM_SD0,
+			 VL53L1X_REG_RESULT__FINAL_CROSSTALK_CORRECTED_RANGE_MM_SD0 + 1),
+	regmap_reg_range(VL53L1X_REG_RESULT__OSC_CALIBRATE_VAL,
+			 VL53L1X_REG_RESULT__OSC_CALIBRATE_VAL + 1),
+	regmap_reg_range(VL53L1X_REG_FIRMWARE__SYSTEM_STATUS,
+			 VL53L1X_REG_FIRMWARE__SYSTEM_STATUS),
+};
+
+static const struct regmap_access_table vl53l1x_volatile_table = {
+	.yes_ranges = vl53l1x_volatile_ranges,
+	.n_yes_ranges = ARRAY_SIZE(vl53l1x_volatile_ranges),
+};
+
+static const struct regmap_range vl53l1x_write_only_ranges[] = {
+	regmap_reg_range(VL53L1X_REG_SOFT_RESET, VL53L1X_REG_SOFT_RESET),
+	regmap_reg_range(VL53L1X_REG_SYSTEM__INTERRUPT_CLEAR,
+			 VL53L1X_REG_SYSTEM__MODE_START),
+};
+
+static const struct regmap_access_table vl53l1x_readable_table = {
+	.no_ranges = vl53l1x_write_only_ranges,
+	.n_no_ranges = ARRAY_SIZE(vl53l1x_write_only_ranges),
+};
+
+static const struct regmap_config vl53l1x_regmap_config = {
+	.reg_bits = 16,
+	.val_bits = 8,
+	/* MODEL_ID is 16-bit. +1 covers the second byte at 0x0110 */
+	.max_register = VL53L1X_REG_IDENTIFICATION__MODEL_ID + 1,
+	.cache_type = REGCACHE_MAPLE,
+	.volatile_table = &vl53l1x_volatile_table,
+	.rd_table = &vl53l1x_readable_table,
+};
+
+static int vl53l1x_read_u16(struct vl53l1x_data *data, u16 reg, u16 *val)
+{
+	__be16 buf;
+	int ret;
+
+	ret = regmap_bulk_read(data->regmap, reg, &buf, sizeof(buf));
+	if (ret)
+		return ret;
+
+	*val = be16_to_cpu(buf);
+	return 0;
+}
+
+static int vl53l1x_write_u16(struct vl53l1x_data *data, u16 reg, u16 val)
+{
+	__be16 buf = cpu_to_be16(val);
+
+	return regmap_bulk_write(data->regmap, reg, &buf, sizeof(buf));
+}
+
+static int vl53l1x_write_u32(struct vl53l1x_data *data, u16 reg, u32 val)
+{
+	__be32 buf = cpu_to_be32(val);
+
+	return regmap_bulk_write(data->regmap, reg, &buf, sizeof(buf));
+}
+
+static int vl53l1x_clear_irq(struct vl53l1x_data *data)
+{
+	return regmap_write(data->regmap, VL53L1X_REG_SYSTEM__INTERRUPT_CLEAR, 0x01);
+}
+
+static int vl53l1x_start_ranging(struct vl53l1x_data *data)
+{
+	int ret;
+
+	ret = vl53l1x_clear_irq(data);
+	if (ret)
+		return ret;
+
+	return regmap_write(data->regmap, VL53L1X_REG_SYSTEM__MODE_START,
+			    VL53L1X_MODE_START_TIMED);
+}
+
+static int vl53l1x_stop_ranging(struct vl53l1x_data *data)
+{
+	return regmap_write(data->regmap, VL53L1X_REG_SYSTEM__MODE_START,
+			    VL53L1X_MODE_START_STOP);
+}
+
+/*
+ * Default configuration blob from ST's VL53L1X Ultra Lite Driver
+ * (STSW-IMG009).
+ */
+static const u8 vl53l1x_default_config[] = {
+	0x00, 0x00, 0x00, 0x01, 0x02, 0x00, 0x02, 0x08,	/* reg 0x2d..0x34 */
+	0x00, 0x08, 0x10, 0x01, 0x01, 0x00, 0x00, 0x00,	/* reg 0x35..0x3c */
+	0x00, 0xFF, 0x00, 0x0F, 0x00, 0x00, 0x00, 0x00,	/* reg 0x3d..0x44 */
+	0x00, 0x20, 0x0B, 0x00, 0x00, 0x02, 0x0A, 0x21,	/* reg 0x45..0x4c */
+	0x00, 0x00, 0x05, 0x00, 0x00, 0x00, 0x00, 0xC8,	/* reg 0x4d..0x54 */
+	0x00, 0x00, 0x38, 0xFF, 0x01, 0x00, 0x08, 0x00,	/* reg 0x55..0x5c */
+	0x00, 0x01, 0xCC, 0x0F, 0x01, 0xF1, 0x0D, 0x01,	/* reg 0x5d..0x64 */
+	0x68, 0x00, 0x80, 0x08, 0xB8, 0x00, 0x00, 0x00,	/* reg 0x65..0x6c */
+	0x00, 0x0F, 0x89, 0x00, 0x00, 0x00, 0x00, 0x00,	/* reg 0x6d..0x74 */
+	0x00, 0x00, 0x01, 0x0F, 0x0D, 0x0E, 0x0E, 0x00,	/* reg 0x75..0x7c */
+	0x00, 0x02, 0xC7, 0xFF, 0x9B, 0x00, 0x00, 0x00,	/* reg 0x7d..0x84 */
+	0x01, 0x00, 0x00,				/* reg 0x85..0x87 */
+};
+
+static int vl53l1x_chip_init(struct vl53l1x_data *data)
+{
+	struct device *dev = regmap_get_device(data->regmap);
+	unsigned int val;
+	u16 model_id;
+	int ret;
+
+	if (!data->xshut_reset) {
+		ret = regmap_write(data->regmap, VL53L1X_REG_SOFT_RESET, 0x00);
+		if (ret)
+			return ret;
+		fsleep(100); /* conservative reset pulse, no spec */
+
+		ret = regmap_write(data->regmap, VL53L1X_REG_SOFT_RESET, 0x01);
+		if (ret)
+			return ret;
+		fsleep(1000); /* conservative boot wait, no spec */
+	}
+
+	ret = regmap_read_poll_timeout(data->regmap,
+				       VL53L1X_REG_FIRMWARE__SYSTEM_STATUS, val,
+				       val & BIT(0),
+				       1 * USEC_PER_MSEC,
+				       100 * USEC_PER_MSEC);
+	if (ret)
+		return dev_err_probe(dev, ret, "firmware boot timeout\n");
+
+	ret = vl53l1x_read_u16(data, VL53L1X_REG_IDENTIFICATION__MODEL_ID,
+			       &model_id);
+	if (ret)
+		return ret;
+
+	if (model_id != VL53L1X_MODEL_ID_VAL)
+		dev_info(dev, "unknown model id: 0x%04x, continuing\n", model_id);
+
+	ret = regmap_bulk_write(data->regmap, VL53L1X_REG_DEFAULT_CONFIG,
+				vl53l1x_default_config,
+				sizeof(vl53l1x_default_config));
+	if (ret)
+		return ret;
+
+	ret = regmap_read(data->regmap, VL53L1X_REG_GPIO_HV_MUX__CTRL, &val);
+	if (ret)
+		return ret;
+	data->gpio_polarity = !!(val & VL53L1X_GPIO_HV_MUX_POLARITY);
+
+	/* Initial ranging cycle for VHV calibration */
+	ret = vl53l1x_start_ranging(data);
+	if (ret)
+		return ret;
+
+	/* 1ms poll, 1s timeout covers max timing budgets (per ST Ultra Lite Driver) */
+	ret = regmap_read_poll_timeout(data->regmap,
+				       VL53L1X_REG_GPIO__TIO_HV_STATUS, val,
+				       (val & 1) != data->gpio_polarity,
+				       1 * USEC_PER_MSEC,
+				       1000 * USEC_PER_MSEC);
+	if (ret)
+		return ret;
+
+	ret = vl53l1x_clear_irq(data);
+	if (ret)
+		return ret;
+
+	ret = vl53l1x_stop_ranging(data);
+	if (ret)
+		return ret;
+
+	ret = regmap_write(data->regmap,
+			   VL53L1X_REG_VHV_CONFIG__TIMEOUT_MACROP_LOOP_BOUND,
+			   VL53L1X_VHV_LOOP_BOUND_TWO);
+	if (ret)
+		return ret;
+
+	return regmap_write(data->regmap, VL53L1X_REG_VHV_CONFIG__INIT, 0x00);
+}
+
+static const struct reg_sequence vl53l1x_mode_short[] = {
+	{ VL53L1X_REG_PHASECAL_CONFIG__TIMEOUT_MACROP,		0x14 },
+	{ VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_A,		0x07 },
+	{ VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_B,		0x05 },
+	{ VL53L1X_REG_RANGE_CONFIG__VALID_PHASE_HIGH,		0x38 },
+	{ VL53L1X_REG_SD_CONFIG__WOI_SD0,			0x07 },
+	{ VL53L1X_REG_SD_CONFIG__WOI_SD1,			0x05 },
+	{ VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD0,		0x06 },
+	{ VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD1,		0x06 },
+};
+
+static const struct reg_sequence vl53l1x_mode_long[] = {
+	{ VL53L1X_REG_PHASECAL_CONFIG__TIMEOUT_MACROP,		0x0A },
+	{ VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_A,		0x0F },
+	{ VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_B,		0x0D },
+	{ VL53L1X_REG_RANGE_CONFIG__VALID_PHASE_HIGH,		0xB8 },
+	{ VL53L1X_REG_SD_CONFIG__WOI_SD0,			0x0F },
+	{ VL53L1X_REG_SD_CONFIG__WOI_SD1,			0x0D },
+	{ VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD0,		0x0E },
+	{ VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD1,		0x0E },
+};
+
+static const struct {
+	const struct reg_sequence *regs;
+	size_t num_regs;
+} vl53l1x_mode_configs[] = {
+	[VL53L1X_SHORT] = { vl53l1x_mode_short, ARRAY_SIZE(vl53l1x_mode_short) },
+	[VL53L1X_LONG]  = { vl53l1x_mode_long, ARRAY_SIZE(vl53l1x_mode_long) },
+};
+
+static int vl53l1x_set_distance_mode(struct vl53l1x_data *data,
+				     enum vl53l1x_distance_mode mode)
+{
+	int ret;
+
+	if (mode >= ARRAY_SIZE(vl53l1x_mode_configs))
+		return -EINVAL;
+
+	ret = regmap_multi_reg_write(data->regmap,
+				     vl53l1x_mode_configs[mode].regs,
+				     vl53l1x_mode_configs[mode].num_regs);
+	if (ret)
+		return ret;
+
+	data->distance_mode = mode;
+	return 0;
+}
+
+/*
+ * The timing budget controls how long the sensor spends collecting
+ * a single range measurement. Pre-computed TIMEOUT_MACROP register
+ * values from ST's VL53L1X Ultra Lite Driver.
+ */
+static int vl53l1x_set_timing_budget(struct vl53l1x_data *data, u16 budget_ms)
+{
+	u16 timeout_a, timeout_b;
+	int ret;
+
+	switch (data->distance_mode) {
+	case VL53L1X_SHORT:
+		switch (budget_ms) {
+		case 15:
+			timeout_a = 0x001D;
+			timeout_b = 0x0027;
+			break;
+		case 20:
+			timeout_a = 0x0051;
+			timeout_b = 0x006E;
+			break;
+		case 33:
+			timeout_a = 0x00D6;
+			timeout_b = 0x006E;
+			break;
+		case 50:
+			timeout_a = 0x01AE;
+			timeout_b = 0x01E8;
+			break;
+		case 100:
+			timeout_a = 0x02E1;
+			timeout_b = 0x0388;
+			break;
+		case 200:
+			timeout_a = 0x03E1;
+			timeout_b = 0x0496;
+			break;
+		case 500:
+			timeout_a = 0x0591;
+			timeout_b = 0x05C1;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	case VL53L1X_LONG:
+		switch (budget_ms) {
+		case 20:
+			timeout_a = 0x001E;
+			timeout_b = 0x0022;
+			break;
+		case 33:
+			timeout_a = 0x0060;
+			timeout_b = 0x006E;
+			break;
+		case 50:
+			timeout_a = 0x00AD;
+			timeout_b = 0x00C6;
+			break;
+		case 100:
+			timeout_a = 0x01CC;
+			timeout_b = 0x01EA;
+			break;
+		case 200:
+			timeout_a = 0x02D9;
+			timeout_b = 0x02F8;
+			break;
+		case 500:
+			timeout_a = 0x048F;
+			timeout_b = 0x04A4;
+			break;
+		default:
+			return -EINVAL;
+		}
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ret = vl53l1x_write_u16(data, VL53L1X_REG_RANGE_CONFIG__TIMEOUT_MACROP_A,
+				timeout_a);
+	if (ret)
+		return ret;
+
+	return vl53l1x_write_u16(data, VL53L1X_REG_RANGE_CONFIG__TIMEOUT_MACROP_B,
+				 timeout_b);
+}
+
+static int vl53l1x_set_inter_measurement_ms(struct vl53l1x_data *data,
+					    u16 period_ms)
+{
+	u16 osc_calibrate_val;
+	u16 clock_pll;
+	u32 inter_meas;
+	int ret;
+
+	ret = vl53l1x_read_u16(data, VL53L1X_REG_RESULT__OSC_CALIBRATE_VAL,
+			       &osc_calibrate_val);
+	if (ret)
+		return ret;
+
+	clock_pll = osc_calibrate_val & VL53L1X_OSC_CALIBRATE_MASK;
+	inter_meas = (clock_pll * period_ms * vl53l1x_osc_correction.numerator) /
+		     vl53l1x_osc_correction.denominator;
+
+	return vl53l1x_write_u32(data,
+				 VL53L1X_REG_SYSTEM__INTERMEASUREMENT_PERIOD,
+				 inter_meas);
+}
+
+static int vl53l1x_read_proximity(struct vl53l1x_data *data, int *val)
+{
+	unsigned int range_status;
+	u16 distance;
+	int ret;
+
+	if (data->irq) {
+		reinit_completion(&data->completion);
+
+		ret = vl53l1x_clear_irq(data);
+		if (ret)
+			return ret;
+
+		if (!wait_for_completion_timeout(&data->completion, HZ))
+			return -ETIMEDOUT;
+	} else {
+		unsigned int rdy;
+
+		/* 1ms poll, 1s timeout covers max timing budgets (per ST Ultra Lite Driver) */
+		ret = regmap_read_poll_timeout(data->regmap,
+					       VL53L1X_REG_GPIO__TIO_HV_STATUS, rdy,
+					       (rdy & 1) != data->gpio_polarity,
+					       1 * USEC_PER_MSEC,
+					       1000 * USEC_PER_MSEC);
+		if (ret)
+			return ret;
+	}
+
+	ret = regmap_read(data->regmap, VL53L1X_REG_RESULT__RANGE_STATUS,
+			  &range_status);
+	if (ret)
+		goto clear_irq;
+
+	if (FIELD_GET(VL53L1X_RANGE_STATUS_MASK, range_status) !=
+	    VL53L1X_RANGE_STATUS_VALID) {
+		ret = -EIO;
+		goto clear_irq;
+	}
+
+	ret = vl53l1x_read_u16(data,
+			       VL53L1X_REG_RESULT__FINAL_CROSSTALK_CORRECTED_RANGE_MM_SD0,
+			       &distance);
+	if (ret)
+		goto clear_irq;
+
+	*val = distance;
+
+clear_irq:
+	vl53l1x_clear_irq(data);
+	return ret;
+}
+
+static const struct iio_chan_spec vl53l1x_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 = 16,
+			.storagebits = 16,
+		},
+	},
+	IIO_CHAN_SOFT_TIMESTAMP(1),
+};
+
+static int vl53l1x_read_raw(struct iio_dev *indio_dev,
+			    const struct iio_chan_spec *chan,
+			    int *val, int *val2, long mask)
+{
+	struct vl53l1x_data *data = iio_priv(indio_dev);
+	int ret;
+
+	if (chan->type != IIO_DISTANCE)
+		return -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		if (!iio_device_claim_direct(indio_dev))
+			return -EBUSY;
+		ret = vl53l1x_read_proximity(data, val);
+		iio_device_release_direct(indio_dev);
+		if (ret)
+			return ret;
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = 0;
+		*val2 = 1000;
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info vl53l1x_info = {
+	.read_raw = vl53l1x_read_raw,
+	.validate_trigger = iio_validate_own_trigger,
+};
+
+static irqreturn_t vl53l1x_trigger_handler(int irq, void *priv)
+{
+	struct iio_poll_func *pf = priv;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct vl53l1x_data *data = iio_priv(indio_dev);
+	struct {
+		u16 distance;
+		aligned_s64 timestamp;
+	} scan = { };
+	unsigned int range_status;
+	int ret;
+
+	ret = regmap_read(data->regmap, VL53L1X_REG_RESULT__RANGE_STATUS,
+			  &range_status);
+	if (ret)
+		goto notify_and_clear_irq;
+	if (FIELD_GET(VL53L1X_RANGE_STATUS_MASK, range_status) !=
+		      VL53L1X_RANGE_STATUS_VALID)
+		goto notify_and_clear_irq;
+
+	ret = vl53l1x_read_u16(data,
+			       VL53L1X_REG_RESULT__FINAL_CROSSTALK_CORRECTED_RANGE_MM_SD0,
+			       &scan.distance);
+	if (ret)
+		goto notify_and_clear_irq;
+
+	iio_push_to_buffers_with_ts(indio_dev, &scan, sizeof(scan),
+				    iio_get_time_ns(indio_dev));
+
+notify_and_clear_irq:
+	iio_trigger_notify_done(indio_dev->trig);
+	vl53l1x_clear_irq(data);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t vl53l1x_irq_handler(int irq, void *priv)
+{
+	struct iio_dev *indio_dev = priv;
+	struct vl53l1x_data *data = iio_priv(indio_dev);
+
+	if (iio_buffer_enabled(indio_dev))
+		iio_trigger_poll(indio_dev->trig);
+	else
+		complete(&data->completion);
+
+	return IRQ_HANDLED;
+}
+
+static const struct iio_trigger_ops vl53l1x_trigger_ops = {
+	.validate_device = iio_trigger_validate_own_device,
+};
+
+static void vl53l1x_stop_ranging_action(void *priv)
+{
+	vl53l1x_stop_ranging(priv);
+}
+
+static int vl53l1x_configure_irq(struct device *dev, int irq,
+				 struct iio_dev *indio_dev)
+{
+	struct vl53l1x_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = devm_request_irq(dev, irq, vl53l1x_irq_handler, IRQF_NO_THREAD,
+			       indio_dev->name, indio_dev);
+	if (ret)
+		return ret;
+
+	ret = regmap_write(data->regmap, VL53L1X_REG_SYSTEM__INTERRUPT_CONFIG_GPIO,
+			   VL53L1X_INT_NEW_SAMPLE_READY);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to configure IRQ\n");
+
+	return 0;
+}
+
+static int vl53l1x_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct vl53l1x_data *data;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	data->irq = client->irq;
+
+	data->regmap = devm_regmap_init_i2c(client, &vl53l1x_regmap_config);
+	if (IS_ERR(data->regmap))
+		return dev_err_probe(dev, PTR_ERR(data->regmap),
+				     "regmap initialization failed\n");
+
+	ret = devm_regulator_get_enable(dev, "vdd");
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to enable VDD regulator\n");
+
+	/*
+	 * XSHUT held low puts the chip in hardware standby. All register
+	 * state is lost on de-assert so this is functionally a reset.
+	 */
+	data->xshut_reset = devm_reset_control_get_optional_exclusive_deasserted(dev, NULL);
+	if (IS_ERR(data->xshut_reset))
+		return dev_err_probe(dev, PTR_ERR(data->xshut_reset),
+				     "Cannot get reset control\n");
+
+	/*
+	 * 1.2 ms max boot duration.
+	 * Datasheet Section 3.6 "Power up and boot sequence".
+	 */
+	fsleep(1200);
+
+	ret = vl53l1x_chip_init(data);
+	if (ret)
+		return ret;
+
+	ret = vl53l1x_set_distance_mode(data, VL53L1X_LONG);
+	if (ret)
+		return ret;
+
+	/* 50 ms timing budget (per ST Ultra Lite Driver) */
+	ret = vl53l1x_set_timing_budget(data, 50);
+	if (ret)
+		return ret;
+
+	/* 50 ms inter-measurement period (per ST Ultra Lite Driver) */
+	ret = vl53l1x_set_inter_measurement_ms(data, 50);
+	if (ret)
+		return ret;
+
+	/*
+	 * The hardware only supports "autonomous" continuous ranging mode.
+	 * Start ranging here and leave it running for the lifetime of
+	 * the device. Both direct reads and the buffer path rely on this.
+	 */
+	ret = vl53l1x_start_ranging(data);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action_or_reset(dev, vl53l1x_stop_ranging_action, data);
+	if (ret)
+		return ret;
+
+	indio_dev->name = "vl53l1x";
+	indio_dev->info = &vl53l1x_info;
+	indio_dev->channels = vl53l1x_channels;
+	indio_dev->num_channels = ARRAY_SIZE(vl53l1x_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	if (client->irq) {
+		struct iio_trigger *trig;
+
+		init_completion(&data->completion);
+
+		trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name,
+					      iio_device_id(indio_dev));
+		if (!trig)
+			return -ENOMEM;
+
+		trig->ops = &vl53l1x_trigger_ops;
+		iio_trigger_set_drvdata(trig, indio_dev);
+		ret = devm_iio_trigger_register(dev, trig);
+		if (ret)
+			return ret;
+
+		indio_dev->trig = iio_trigger_get(trig);
+
+		ret = vl53l1x_configure_irq(dev, client->irq, indio_dev);
+		if (ret)
+			return ret;
+
+		ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
+						      &vl53l1x_trigger_handler,
+						      NULL);
+		if (ret)
+			return ret;
+	}
+
+	return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct i2c_device_id vl53l1x_id[] = {
+	{ "vl53l1x" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, vl53l1x_id);
+
+static const struct of_device_id st_vl53l1x_dt_match[] = {
+	{ .compatible = "st,vl53l1x" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, st_vl53l1x_dt_match);
+
+static struct i2c_driver vl53l1x_driver = {
+	.driver = {
+		.name = "vl53l1x-i2c",
+		.of_match_table = st_vl53l1x_dt_match,
+	},
+	.probe = vl53l1x_probe,
+	.id_table = vl53l1x_id,
+};
+module_i2c_driver(vl53l1x_driver);
+
+MODULE_AUTHOR("Siratul Islam <email@sirat.me>");
+MODULE_DESCRIPTION("ST VL53L1X ToF ranging sensor driver");
+MODULE_LICENSE("Dual BSD/GPL");
-- 
2.53.0

Re: [PATCH v8 2/2] iio: proximity: add driver for ST VL53L1X ToF sensor

[Andy Shevchenko]

On Thu, Mar 26, 2026 at 02:19:42AM +0600, Siratul Islam wrote:
> Add support for the STMicroelectronics VL53L1X Time-of-Flight
> ranging sensor with I2C interface.

Some ideas for small followup amendments.

...

> +#define VL53L1X_REG_SOFT_RESET						0x0000
> +#define VL53L1X_REG_VHV_CONFIG__TIMEOUT_MACROP_LOOP_BOUND		0x0008
> +#define VL53L1X_REG_VHV_CONFIG__INIT					0x000B
> +#define VL53L1X_REG_GPIO_HV_MUX__CTRL					0x0030
> +#define VL53L1X_REG_GPIO__TIO_HV_STATUS					0x0031
> +#define VL53L1X_REG_SYSTEM__INTERRUPT_CONFIG_GPIO			0x0046
> +#define VL53L1X_REG_PHASECAL_CONFIG__TIMEOUT_MACROP			0x004B
> +#define VL53L1X_REG_RANGE_CONFIG__TIMEOUT_MACROP_A			0x005E
> +#define VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_A			0x0060
> +#define VL53L1X_REG_RANGE_CONFIG__TIMEOUT_MACROP_B			0x0061
> +#define VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_B			0x0063
> +#define VL53L1X_REG_RANGE_CONFIG__VALID_PHASE_HIGH			0x0069
> +#define VL53L1X_REG_SYSTEM__INTERMEASUREMENT_PERIOD			0x006C
> +#define VL53L1X_REG_SD_CONFIG__WOI_SD0					0x0078
> +#define VL53L1X_REG_SD_CONFIG__WOI_SD1					0x0079
> +#define VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD0			0x007A
> +#define VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD1			0x007B
> +#define VL53L1X_REG_SYSTEM__INTERRUPT_CLEAR				0x0086
> +#define VL53L1X_REG_SYSTEM__MODE_START					0x0087
> +#define VL53L1X_REG_RESULT__RANGE_STATUS				0x0089
> +#define VL53L1X_REG_RESULT__FINAL_CROSSTALK_CORRECTED_RANGE_MM_SD0	0x0096
> +#define VL53L1X_REG_RESULT__OSC_CALIBRATE_VAL				0x00DE
> +#define VL53L1X_REG_FIRMWARE__SYSTEM_STATUS				0x00E5
> +#define VL53L1X_REG_IDENTIFICATION__MODEL_ID				0x010F
> +#define VL53L1X_REG_DEFAULT_CONFIG					0x002D

Keep the list ordered by the value?

...

> +static int vl53l1x_chip_init(struct vl53l1x_data *data)
> +{
> +	struct device *dev = regmap_get_device(data->regmap);
> +	unsigned int val;
> +	u16 model_id;
> +	int ret;
> +
> +	if (!data->xshut_reset) {
> +		ret = regmap_write(data->regmap, VL53L1X_REG_SOFT_RESET, 0x00);
> +		if (ret)
> +			return ret;
> +		fsleep(100); /* conservative reset pulse, no spec */
> +
> +		ret = regmap_write(data->regmap, VL53L1X_REG_SOFT_RESET, 0x01);
> +		if (ret)
> +			return ret;
> +		fsleep(1000); /* conservative boot wait, no spec */
> +	}
> +
> +	ret = regmap_read_poll_timeout(data->regmap,
> +				       VL53L1X_REG_FIRMWARE__SYSTEM_STATUS, val,
> +				       val & BIT(0),
> +				       1 * USEC_PER_MSEC,
> +				       100 * USEC_PER_MSEC);

Use logical split

	ret = regmap_read_poll_timeout(data->regmap,
				       VL53L1X_REG_FIRMWARE__SYSTEM_STATUS,
				       val, val & BIT(0),
				       1 * USEC_PER_MSEC, 100 * USEC_PER_MSEC);

> +	if (ret)
> +		return dev_err_probe(dev, ret, "firmware boot timeout\n");
> +
> +	ret = vl53l1x_read_u16(data, VL53L1X_REG_IDENTIFICATION__MODEL_ID,
> +			       &model_id);
> +	if (ret)
> +		return ret;
> +
> +	if (model_id != VL53L1X_MODEL_ID_VAL)
> +		dev_info(dev, "unknown model id: 0x%04x, continuing\n", model_id);
> +
> +	ret = regmap_bulk_write(data->regmap, VL53L1X_REG_DEFAULT_CONFIG,
> +				vl53l1x_default_config,
> +				sizeof(vl53l1x_default_config));
> +	if (ret)
> +		return ret;
> +
> +	ret = regmap_read(data->regmap, VL53L1X_REG_GPIO_HV_MUX__CTRL, &val);
> +	if (ret)
> +		return ret;
> +	data->gpio_polarity = !!(val & VL53L1X_GPIO_HV_MUX_POLARITY);
> +
> +	/* Initial ranging cycle for VHV calibration */
> +	ret = vl53l1x_start_ranging(data);
> +	if (ret)
> +		return ret;
> +
> +	/* 1ms poll, 1s timeout covers max timing budgets (per ST Ultra Lite Driver) */
> +	ret = regmap_read_poll_timeout(data->regmap,
> +				       VL53L1X_REG_GPIO__TIO_HV_STATUS, val,
> +				       (val & 1) != data->gpio_polarity,
> +				       1 * USEC_PER_MSEC,
> +				       1000 * USEC_PER_MSEC);

Ditto.

	ret = regmap_read_poll_timeout(data->regmap,
				       VL53L1X_REG_GPIO__TIO_HV_STATUS,
				       val, (val & 1) != data->gpio_polarity,
				       1 * USEC_PER_MSEC, 1 * USEC_PER_SEC);

> +	if (ret)
> +		return ret;
> +
> +	ret = vl53l1x_clear_irq(data);
> +	if (ret)
> +		return ret;
> +
> +	ret = vl53l1x_stop_ranging(data);
> +	if (ret)
> +		return ret;
> +
> +	ret = regmap_write(data->regmap,
> +			   VL53L1X_REG_VHV_CONFIG__TIMEOUT_MACROP_LOOP_BOUND,
> +			   VL53L1X_VHV_LOOP_BOUND_TWO);
> +	if (ret)
> +		return ret;
> +
> +	return regmap_write(data->regmap, VL53L1X_REG_VHV_CONFIG__INIT, 0x00);
> +}

...

> +	if (data->irq) {
> +		reinit_completion(&data->completion);
> +
> +		ret = vl53l1x_clear_irq(data);
> +		if (ret)
> +			return ret;
> +
> +		if (!wait_for_completion_timeout(&data->completion, HZ))
> +			return -ETIMEDOUT;
> +	} else {
> +		unsigned int rdy;
> +
> +		/* 1ms poll, 1s timeout covers max timing budgets (per ST Ultra Lite Driver) */
> +		ret = regmap_read_poll_timeout(data->regmap,
> +					       VL53L1X_REG_GPIO__TIO_HV_STATUS, rdy,
> +					       (rdy & 1) != data->gpio_polarity,
> +					       1 * USEC_PER_MSEC,
> +					       1000 * USEC_PER_MSEC);

Ditto.

		ret = regmap_read_poll_timeout(data->regmap,
					       VL53L1X_REG_GPIO__TIO_HV_STATUS,
					       rdy, (rdy & 1) != data->gpio_polarity,
					       1 * USEC_PER_MSEC, 1 * USEC_PER_SEC);

Yes, in this case they are slightly longer than 80 characters. But
looking at the above this entire call should be a helper, so you can
reuse it here and above.

> +		if (ret)
> +			return ret;
> +	}

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v8 2/2] iio: proximity: add driver for ST VL53L1X ToF sensor

[Sirat]

On Thu, Mar 26, 2026 at 4:14 PM Andy Shevchenko
<andriy.shevchenko@intel.com> wrote:
>
> On Thu, Mar 26, 2026 at 02:19:42AM +0600, Siratul Islam wrote:
> > Add support for the STMicroelectronics VL53L1X Time-of-Flight
> > ranging sensor with I2C interface.
>
> Some ideas for small followup amendments.
>
> ...
>
> > +#define VL53L1X_REG_SOFT_RESET                                               0x0000
> > +#define VL53L1X_REG_VHV_CONFIG__TIMEOUT_MACROP_LOOP_BOUND            0x0008
> > +#define VL53L1X_REG_VHV_CONFIG__INIT                                 0x000B
> > +#define VL53L1X_REG_GPIO_HV_MUX__CTRL                                        0x0030
> > +#define VL53L1X_REG_GPIO__TIO_HV_STATUS                                      0x0031
> > +#define VL53L1X_REG_SYSTEM__INTERRUPT_CONFIG_GPIO                    0x0046
> > +#define VL53L1X_REG_PHASECAL_CONFIG__TIMEOUT_MACROP                  0x004B
> > +#define VL53L1X_REG_RANGE_CONFIG__TIMEOUT_MACROP_A                   0x005E
> > +#define VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_A                     0x0060
> > +#define VL53L1X_REG_RANGE_CONFIG__TIMEOUT_MACROP_B                   0x0061
> > +#define VL53L1X_REG_RANGE_CONFIG__VCSEL_PERIOD_B                     0x0063
> > +#define VL53L1X_REG_RANGE_CONFIG__VALID_PHASE_HIGH                   0x0069
> > +#define VL53L1X_REG_SYSTEM__INTERMEASUREMENT_PERIOD                  0x006C
> > +#define VL53L1X_REG_SD_CONFIG__WOI_SD0                                       0x0078
> > +#define VL53L1X_REG_SD_CONFIG__WOI_SD1                                       0x0079
> > +#define VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD0                     0x007A
> > +#define VL53L1X_REG_SD_CONFIG__INITIAL_PHASE_SD1                     0x007B
> > +#define VL53L1X_REG_SYSTEM__INTERRUPT_CLEAR                          0x0086
> > +#define VL53L1X_REG_SYSTEM__MODE_START                                       0x0087
> > +#define VL53L1X_REG_RESULT__RANGE_STATUS                             0x0089
> > +#define VL53L1X_REG_RESULT__FINAL_CROSSTALK_CORRECTED_RANGE_MM_SD0   0x0096
> > +#define VL53L1X_REG_RESULT__OSC_CALIBRATE_VAL                                0x00DE
> > +#define VL53L1X_REG_FIRMWARE__SYSTEM_STATUS                          0x00E5
> > +#define VL53L1X_REG_IDENTIFICATION__MODEL_ID                         0x010F
> > +#define VL53L1X_REG_DEFAULT_CONFIG                                   0x002D
>
> Keep the list ordered by the value?
>
> ...
>
> > +static int vl53l1x_chip_init(struct vl53l1x_data *data)
> > +{
> > +     struct device *dev = regmap_get_device(data->regmap);
> > +     unsigned int val;
> > +     u16 model_id;
> > +     int ret;
> > +
> > +     if (!data->xshut_reset) {
> > +             ret = regmap_write(data->regmap, VL53L1X_REG_SOFT_RESET, 0x00);
> > +             if (ret)
> > +                     return ret;
> > +             fsleep(100); /* conservative reset pulse, no spec */
> > +
> > +             ret = regmap_write(data->regmap, VL53L1X_REG_SOFT_RESET, 0x01);
> > +             if (ret)
> > +                     return ret;
> > +             fsleep(1000); /* conservative boot wait, no spec */
> > +     }
> > +
> > +     ret = regmap_read_poll_timeout(data->regmap,
> > +                                    VL53L1X_REG_FIRMWARE__SYSTEM_STATUS, val,
> > +                                    val & BIT(0),
> > +                                    1 * USEC_PER_MSEC,
> > +                                    100 * USEC_PER_MSEC);
>
> Use logical split
>
>         ret = regmap_read_poll_timeout(data->regmap,
>                                        VL53L1X_REG_FIRMWARE__SYSTEM_STATUS,
>                                        val, val & BIT(0),
>                                        1 * USEC_PER_MSEC, 100 * USEC_PER_MSEC);
>
> > +     if (ret)
> > +             return dev_err_probe(dev, ret, "firmware boot timeout\n");
> > +
> > +     ret = vl53l1x_read_u16(data, VL53L1X_REG_IDENTIFICATION__MODEL_ID,
> > +                            &model_id);
> > +     if (ret)
> > +             return ret;
> > +
> > +     if (model_id != VL53L1X_MODEL_ID_VAL)
> > +             dev_info(dev, "unknown model id: 0x%04x, continuing\n", model_id);
> > +
> > +     ret = regmap_bulk_write(data->regmap, VL53L1X_REG_DEFAULT_CONFIG,
> > +                             vl53l1x_default_config,
> > +                             sizeof(vl53l1x_default_config));
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = regmap_read(data->regmap, VL53L1X_REG_GPIO_HV_MUX__CTRL, &val);
> > +     if (ret)
> > +             return ret;
> > +     data->gpio_polarity = !!(val & VL53L1X_GPIO_HV_MUX_POLARITY);
> > +
> > +     /* Initial ranging cycle for VHV calibration */
> > +     ret = vl53l1x_start_ranging(data);
> > +     if (ret)
> > +             return ret;
> > +
> > +     /* 1ms poll, 1s timeout covers max timing budgets (per ST Ultra Lite Driver) */
> > +     ret = regmap_read_poll_timeout(data->regmap,
> > +                                    VL53L1X_REG_GPIO__TIO_HV_STATUS, val,
> > +                                    (val & 1) != data->gpio_polarity,
> > +                                    1 * USEC_PER_MSEC,
> > +                                    1000 * USEC_PER_MSEC);
>
> Ditto.
>
>         ret = regmap_read_poll_timeout(data->regmap,
>                                        VL53L1X_REG_GPIO__TIO_HV_STATUS,
>                                        val, (val & 1) != data->gpio_polarity,
>                                        1 * USEC_PER_MSEC, 1 * USEC_PER_SEC);
>
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = vl53l1x_clear_irq(data);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = vl53l1x_stop_ranging(data);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = regmap_write(data->regmap,
> > +                        VL53L1X_REG_VHV_CONFIG__TIMEOUT_MACROP_LOOP_BOUND,
> > +                        VL53L1X_VHV_LOOP_BOUND_TWO);
> > +     if (ret)
> > +             return ret;
> > +
> > +     return regmap_write(data->regmap, VL53L1X_REG_VHV_CONFIG__INIT, 0x00);
> > +}
>
> ...
>
> > +     if (data->irq) {
> > +             reinit_completion(&data->completion);
> > +
> > +             ret = vl53l1x_clear_irq(data);
> > +             if (ret)
> > +                     return ret;
> > +
> > +             if (!wait_for_completion_timeout(&data->completion, HZ))
> > +                     return -ETIMEDOUT;
> > +     } else {
> > +             unsigned int rdy;
> > +
> > +             /* 1ms poll, 1s timeout covers max timing budgets (per ST Ultra Lite Driver) */
> > +             ret = regmap_read_poll_timeout(data->regmap,
> > +                                            VL53L1X_REG_GPIO__TIO_HV_STATUS, rdy,
> > +                                            (rdy & 1) != data->gpio_polarity,
> > +                                            1 * USEC_PER_MSEC,
> > +                                            1000 * USEC_PER_MSEC);
>
> Ditto.
>
>                 ret = regmap_read_poll_timeout(data->regmap,
>                                                VL53L1X_REG_GPIO__TIO_HV_STATUS,
>                                                rdy, (rdy & 1) != data->gpio_polarity,
>                                                1 * USEC_PER_MSEC, 1 * USEC_PER_SEC);
>
> Yes, in this case they are slightly longer than 80 characters. But
> looking at the above this entire call should be a helper, so you can
> reuse it here and above.
>
> > +             if (ret)
> > +                     return ret;
> > +     }
>
> --
> With Best Regards,
> Andy Shevchenko
>
>
>
Hi Andy!

Thanks for the review again. I will send a small separate cleanup
patch for this once it gets to a more stable stage.

Sirat

Re: [PATCH v8 0/2] iio: proximity: add driver for ST VL53L1X ToF sensor

[Jonathan Cameron]

On Thu, 26 Mar 2026 02:19:40 +0600
Siratul Islam <email@sirat.me> wrote:

> This series adds support for the STMicroelectronics VL53L1X
> Time-of-Flight ranging sensor.
> 
> The VL53L1X is a ToF laser-ranging sensor with I2C interface,
> capable of measuring distances up to 4 meters. The driver
> supports both interrupt-driven and polled operation.
> 
> Why a separate driver is needed (instead of extending vl53l0x-i2c.c):
> The VL53L1X is fundamentally different from the VL53L0X despite the
> similar naming. Extending the existing driver would require rewriting
> the majority of it.
> 
> Key differences include:
> - A different register map (16-bit addresses vs. 8-bit addresses).
> - Requires a 91-byte firmware configuration blob to be loaded at boot.
> - Requires a VHV calibration cycle.
> - Has distance mode and timing budget configurations.
> - Uses the regmap API rather than raw i2c_smbus calls.
> 
> I also reviewed other drivers in drivers/iio/proximity/ and can
> confirm this IP block does not appear to be shared by any other
> existing driver.
> 
> Tested on Raspberry Pi 5 with a VL53L1X breakout board.
> 
> Note on vdd-supply:
> vdd-supply is required for st,vl53l1x. It is not globally required
> for backwards compatibility with existing st,vl53l0x devicetrees
> that omit it.
Applied to the testing branch of iio.git.

Thanks,

J
> 
> ---
> Changes in v8:
> - Use devm_regulator_get_enable() and devm_reset_control_get_optional_exclusive_deasserted().
> - Drop i2c_check_functionality().
> - Remove power_on/power_off helpers.
> - Require vdd-supply only for st,vl53l1x.
> 
> 
> Changes in v7:
> - Add VL53L1X_REG_ prefix for register defines.
> - Use iio_push_to_buffers_with_ts().
> - Use continuous ranging and drop postenable/predisable.
> - Add comments for XSHUT reset, default config values.
> - Drop vdd-supply description in binding and comment in driver.
> - Add ABI rationale for vdd-supply to commit message (per Krzysztof, Jonathan).
> 
> 
> Changes in v6:
> - Make vdd-supply required. Add descriptions to vdd-supply and reset-gpios (per Jonathan).
> - Check reset_control_deassert() return value (per Andy).
> - Use volatile table for result registers and caching for the rest. Also mark write-only registers.
> - Drop tag from Krzysztof Kozlowski for vdd-supply requirement change.
> 
> Changes in v5:
> - Patch 1: No changes. Collected Reviewed-by tag from Krzysztof Kozlowski.
> - Switch XSHUT pin handling from the GPIO consumer API to the Reset controller API.
> - Drop <linux/gpio/consumer.h> and include <linux/reset.h>.
> 
> 
> Changes in v4:
> - Move i2c_check_functionality() to the top of probe before allocations.
> - Use struct u32_fract for oscillator correction math.
> - Explicitly set .cache_type = REGCACHE_NONE.
> - Document intentional predisable drain
> - Use dev_err_probe() for firmware boot timeout and remove duplicate IRQ request error message.
> - Use sizeof() in regmap bulk read/writes instead of hardcoded lengths.
> - Add missing headers (<linux/math.h>, <linux/time.h>, <asm/byteorder.h>).
> - Various formatting cleanups per Andy's review.
> 
> 
> Changes in v3:
> - Merge DT binding into existing st,vl53l0x.yaml (per Krzysztof).
> - Use "reset-gpios" in the binding but xshut_gpio in the driver since that's the actual pin name.
> - Replace manual polling loops in chip_init and read_proximity with regmap_read_poll_timeout().
> - Remove irq_get_trigger_type() and pass IRQF_NO_THREAD directly (per Andy).
> - Drop struct i2c_client from private data and store irq as int instead. Derive struct device from regmap where needed.
> - Add dev_err_probe() to first devm_request_irq() error path.
> - Replace linux/device.h with linux/dev_printk.h, add linux/array_size.h, linux/err.h, linux/types.h (per Andy).
> - Use USEC_PER_MSEC for poll timeouts.
> - Remove unnecessary casts.
> - Divide long config blob to 8 values per line.
> - Rename goto label to notify_and_clear_irq and drop unused dev_dbg.
> - Add datasheet section reference for boot delay comment.
> - vdd-supply no longer required in shared binding to avoid breaking existing st,vl53l0x devicetrees.
> 
> 
> Changes in v2:
> - Skip software reset in chip_init when xshut GPIO is available, since the device was already hardware-reset during power-on.
> - Rename "reset" GPIO to "xshut" to match the datasheet pin name and updated DT binding accordingly.
> - Make vdd-supply required in DT binding.
> - Use reg_sequence arrays and regmap_multi_reg_write() for distance mode configuration.
> - Switch to a hardirq handler with iio_trigger_poll() and IRQF_NO_THREAD instead of a threaded handler.
> - Drop IRQF_TRIGGER_FALLING fallback. Leave trigger type to firmware/DT.
> - Use iio_validate_own_trigger() instead of a custom validate_trigger, drop trig pointer from driver data.
> - Switch usleep_range() to fsleep() throughout and add comments for sleep values.
> - Don't fail probe on unknown model ID, just log with dev_info().
> - Split stop_ranging cleanup into its own devm action, separate from power_off.
> - Add missing includes: device.h, bitfield.h, completion.h, mod_devicetable.h.
> - Use FIELD_GET() for range status checks.
> - Move configure_irq() closer to probe(), use dev_err_probe() for its error paths.
> - Fix buffer ops symmetry: postdisable -> predisable.
> - Drop reg_format_endian from regmap config.
> - Various alignment and formatting fixes.
> 
> Link to v7: https://lore.kernel.org/linux-iio/20260325063254.18062-1-email@sirat.me
> Link to v6: https://lore.kernel.org/linux-iio/20260319190738.151614-1-email@sirat.me
> Link to v5: https://lore.kernel.org/linux-iio/20260313113737.151881-1-email@sirat.me
> Link to v4: https://lore.kernel.org/linux-iio/20260312183721.40482-1-email@sirat.me
> Link to v3: https://lore.kernel.org/linux-iio/20260311224044.21480-1-email@sirat.me
> Link to v2: https://lore.kernel.org/linux-iio/20260308113728.40860-1-email@sirat.me
> Link to v1: https://lore.kernel.org/linux-iio/20260303090253.42076-1-email@sirat.me
> 
> Siratul Islam (2):
>   dt-bindings: iio: proximity: add ST VL53L1X ToF sensor
>   iio: proximity: add driver for ST VL53L1X ToF sensor
> 
>  .../bindings/iio/proximity/st,vl53l0x.yaml    |  24 +-
>  MAINTAINERS                                   |   7 +
>  drivers/iio/proximity/Kconfig                 |  15 +
>  drivers/iio/proximity/Makefile                |   1 +
>  drivers/iio/proximity/vl53l1x-i2c.c           | 756 ++++++++++++++++++
>  5 files changed, 800 insertions(+), 3 deletions(-)
>  create mode 100644 drivers/iio/proximity/vl53l1x-i2c.c
> 
> --
> 2.53.0
> 
> 

Re: [PATCH v8 0/2] iio: proximity: add driver for ST VL53L1X ToF sensor

[Sirat]

On Thu, Mar 26, 2026 at 2:25 PM Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Thu, 26 Mar 2026 02:19:40 +0600
> Siratul Islam <email@sirat.me> wrote:
>
...
> Applied to the testing branch of iio.git.
>
> Thanks,
>
> J

Thanks for applying the patch. Thanks to you and all the reviewers.
The code it ended up becoming is much superior to what I initially
had.

Best regards
Sirat