[PATCH v8 0/3] iio: proximity: Add TYHX HX9023S sensor driver

[PATCH v8 0/3] iio: proximity: Add TYHX HX9023S sensor driver

[Yasin Lee]

Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>
---
Changes in v8:
- Removed incorrect tags from the commit messages 
- Removed duplicate properties in the dt-binding.
- Link to v7: https://lore.kernel.org/r/20240625-add-tyhx-hx9023s-sensor-driver-v7-0-b1d65b221811@gmail.com

Changes in v7:

**tyhx,hx9023s.yaml:**

- Removed the unused reference to iio.yaml
- Removed the `input-channel` property and switched to inheriting the `single-channel` property from adc.yaml
- Sorted the items in the `required` list

**hx9023s.c:**

- Header Files Section:
  - Added `<linux/cleanup.h>`
  - Removed `<linux/delay.h>`
  - Replaced `<linux/math.h>` with `<linux/math64.h>`
- Register Initialization:
  - Deleted the `struct hx9023s_addr_val_pair`
  - Changed the type of `hx9023s_reg_init_list` to `struct reg_sequence`
  - Deleted the `hx9023s_reg_init` function and used `regmap_multi_reg_write` for register initialization in `probe`
- struct hx9023s_ch_data:
  - Added a comment to the member `mutex` explaining the data it protects
- Function hx9023s_sample:
  - Fixed the error related to `hx9023s_data_lock` calls
- Function hx9023s_property_get:
  - Added boundary protection for `reg`
- Function hx9023s_id_check:
  - Optimized the function
- Function hx9023s_probe:
  - Changed the call to `devm_iio_device_register` to `return devm_iio_device_register()`
- Functions hx9023s_suspend and hx9023s_resume:
  - Added `guard(mutex)(&data->mutex)`
- Code Check:
  - Ran `checkpatch.pl --strict` and fixed the identified issues
- Link to v6: https://lore.kernel.org/r/20240621-add-tyhx-hx9023s-sensor-driver-v6-0-65196a9020f1@gmail.com

Changes in v6:

**vendor-prefixes.yaml:**

- Formatted the description in the commit

**tyhx,hx9023s.yaml:**

- Added a link to the DataSheet
- Added `#address-cells` and `#size-cells`
- Removed the following properties:
  - `channel-in-use`
  - `channel-positive`
  - `channel-negative`
- Corrected the reference path to `adc.yaml`
- Inherited `diff-channels` from `adc.yaml` as differential channels
- Added `input-channel` property as a single-ended configuration channel
- Made `vdd-supply` a required option
- Used the generic name `proximity` instead of the chip name in the DTS example

**hx9023s.c:**

- Removed the following headers:
  - `#include <linux/acpi.h>`
  - `#include <linux/byteorder/generic.h>`
  - `#include <linux/kernel.h>`
- Added `#include <asm/byteorder.h>`
- Updated some macro names:
  - `HX9023S_DATA_2BYTES` ---> `HX9023S_2BYTES`
  - `HX9023S_DATA_3BYTES` ---> `HX9023S_3BYTES`
  - `HX9023S_DATA_BYTES_MAX` ---> `HX9023S_BYTES_MAX`
- Added the following macro definitions:
  - `#define HX9023S_POS 0x03`
  - `#define HX9023S_NEG 0x02`
  - `#define HX9023S_NOT_CONNECTED 16`
  - `#define HX9023S_GLOBAL_CTRL0 0x00`
- `struct hx9023s_ch_data`:
  - Added comments explaining the members `raw`, `lp`, `bl`, `diff`
  - Changed the type of struct member `thre` from `int` to `unsigned int`
  - Removed member `cs_position`
  - Changed the type of `struct buffer` member `channels[HX9023S_CH_NUM]` from `__be16` to `__le16`
  - Moved `struct hx9023s_ch_data ch_data` to the bottom
- Updated comments in the array `hx9023s_reg_init_list`:
  - Changed `adc` to `ADC`, `avg` to `average`, and `osr` to `OSR`
  - Provided a more detailed comment for the register `HX9023S_RAW_BL_RD_CFG`
- `struct regmap_config hx9023s_regmap_config`:
  - Added `.rd_type` member
  - Changed `.cache_type` from `REGCACHE_RBTREE` to `REGCACHE_MAPLE`
- Bugfix: The function `hx9023s_data_lock` now only operates on one bit instead of two
- `hx9023s_ch_cfg` function:
  - Replaced magic characters with meaningful macro definitions
  - Changed byte concatenation operations to use `put_unaligned_le16`
- Reviewed each function and made the following changes:
  - Some returns now directly return `regmap_read/write()`
  - For single-byte write operations, changed from `regmap_bulk_write(,,,1)` to `regmap_write(,,)`
  - Changed the type of loop variable `i` to `unsigned`
- `hx9023s_write_far_debounce` and `hx9023s_write_near_debounce` functions:
  - Removed magic numbers and optimized the code
- `hx9023s_get_thres_near` and `hx9023s_get_thres_far` functions:
  - Used intermediate variables for readability and simplified the code logic
- `hx9023s_set_thres_near` and `hx9023s_set_thres_far` functions:
  - Optimized the logic and simplified the code
- `hx9023s_get_prox_state` function:
  - Changed the return value type to `int`
- `hx9023s_data_select` function:
  - Changed the return value type to `int`
- `hx9023s_sample` function:
  - Added intermediate variables for better readability
- `hx9023s_ch_en` function:
  - Optimized the code logic to reduce line count
- `hx9023s_property_get` function:
  - Rewritten due to DTS changes, and calls `fwnode_handle_put` on error to prevent memory leaks
- `hx9023s_get_proximity` function:
  - Added error handling logic for data
- `hx9023s_get_samp_freq` function:
  - Used macro definitions from `units.h` instead of specific numbers for frequency calculation
- `hx9023s_set_samp_freq` function:
  - Used macro definitions from `units.h` instead of specific numbers for frequency calculation
- `hx9023s_write_raw` function:
  - Changed the type of local variable `dir` to `unsigned`
- `hx9023s_write_event_config` function:
  - Replaced `set_bit` and `clear_bit` with `__assign_bit`
- `hx9023s_trigger_handler` function:
  - Added error handling logic for data; fixed uninitialized variable `i` bug
- `hx9023s_buffer_preenable` function:
  - Fixed uninitialized variable `channel` bug
- Added `hx9023s_id_check` function
- `hx9023s_probe` function:
  - Returns directly on `devm_iio_device_alloc` error, without logging; removed `fsleep`
- `hx9023s_resume` function:
  - Calls `hx9023s_interrupt_enable` only when `data->trigger_enabled` is true
- Removed `hx9023s_acpi_match`
- Link to v5: https://lore.kernel.org/linux-iio/SN7PR12MB8101B6D0AB1246797C67E25BA4CE2@SN7PR12MB8101.namprd12.prod.outlook.com/

Changes in v5:
- I have addressed all the issues mentioned in the email responses.
  Additionally, regarding the IIO-related header files, I have checked and found no unused headers.
- Link to v4: https://lore.kernel.org/linux-iio/SN7PR12MB810129D8180B1C9593A8E078A4FB2@SN7PR12MB8101.namprd12.prod.outlook.com/

Changes in v4:
- Removed hardware-irrelevant properties from dt-bindings, retaining only channel configuration
  related `channel-positive` and `channel-negative`. Grouped by channel.
  Retained `channel-in-use` as it is hardware-related.
- Removed redundant register definitions.
- Reorganized `struct hx9023s_data`, extracting channel-related attributes
  into a new `struct hx9023s_ch_data`.
- Optimized bit operation related code.
- Replaced `of_` versions with generic firmware parsing functions.
- Fixed other issues mentioned in the email feedback.
- Link to v3: https://lore.kernel.org/linux-iio/20240602152638.2c674930@jic23-huawei/

---
Yasin Lee (3):
      dt-bindings: vendor-prefixes: add tyhx
      dt-bindings: iio: proximity: Add TYHX HX9023S
      iio: proximity: Add driver support for TYHX's HX9023S capacitive proximity sensor

 .../bindings/iio/proximity/tyhx,hx9023s.yaml       |   93 ++
 .../devicetree/bindings/vendor-prefixes.yaml       |    2 +
 drivers/iio/proximity/Kconfig                      |   14 +
 drivers/iio/proximity/Makefile                     |    1 +
 drivers/iio/proximity/hx9023s.c                    | 1131 ++++++++++++++++++++
 5 files changed, 1241 insertions(+)
---
base-commit: 1231e065edd236295c31904fe760117551608efa
change-id: 20240616-add-tyhx-hx9023s-sensor-driver-e7dbe3bfe596

Best regards,
-- 
Yasin Lee <yasin.lee.x@gmail.com>

[PATCH v8 1/3] dt-bindings: vendor-prefixes: add tyhx

[Yasin Lee]

Add vendor prefix for NanjingTianyihexin Electronics Ltd.
http://www.tianyihexin.com

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index bbae442d01d2..d7d15c9f30e3 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -1529,6 +1529,8 @@ patternProperties:
     description: Turing Machines, Inc.
   "^tyan,.*":
     description: Tyan Computer Corporation
+  "^tyhx,.*":
+    description: NanjingTianyihexin Electronics Ltd.
   "^u-blox,.*":
     description: u-blox
   "^u-boot,.*":

-- 
2.25.1

[PATCH v8 2/3] dt-bindings: iio: proximity: Add TYHX HX9023S

[Yasin Lee]

A capacitive proximity sensor

Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>
---
 .../bindings/iio/proximity/tyhx,hx9023s.yaml       | 93 ++++++++++++++++++++++
 1 file changed, 93 insertions(+)

diff --git a/Documentation/devicetree/bindings/iio/proximity/tyhx,hx9023s.yaml b/Documentation/devicetree/bindings/iio/proximity/tyhx,hx9023s.yaml
new file mode 100644
index 000000000000..64ce8bc8bd36
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/proximity/tyhx,hx9023s.yaml
@@ -0,0 +1,93 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/proximity/tyhx,hx9023s.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: TYHX HX9023S capacitive proximity sensor
+
+maintainers:
+  - Yasin Lee <yasin.lee.x@gmail.com>
+
+description: |
+  TYHX HX9023S proximity sensor. Datasheet can be found here:
+    http://www.tianyihexin.com/ueditor/php/upload/file/20240614/1718336303992081.pdf
+
+properties:
+  compatible:
+    const: tyhx,hx9023s
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    description:
+      Generated by device to announce preceding read request has finished
+      and data is available or that a close/far proximity event has happened.
+    maxItems: 1
+
+  vdd-supply: true
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+patternProperties:
+  "^channel@[0-4]$":
+    $ref: /schemas/iio/adc/adc.yaml
+    type: object
+    unevaluatedProperties: false
+
+    properties:
+      reg:
+        minimum: 0
+        maximum: 4
+        description: The channel number.
+
+required:
+  - compatible
+  - reg
+  - vdd-supply
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+      proximity@2a {
+        compatible = "tyhx,hx9023s";
+        reg = <0x2a>;
+        interrupt-parent = <&pio>;
+        interrupts = <16 IRQ_TYPE_EDGE_FALLING>;
+        vdd-supply = <&pp1800_prox>;
+
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        channel@0 {
+          reg = <0>;
+          single-channel = <0>;
+        };
+        channel@1 {
+          reg = <1>;
+          single-channel = <1>;
+        };
+        channel@2 {
+          reg = <2>;
+          single-channel = <2>;
+        };
+        channel@3 {
+          reg = <3>;
+          diff-channels = <1 0>;
+        };
+        channel@4 {
+          reg = <4>;
+          diff-channels = <2 0>;
+        };
+      };
+    };

-- 
2.25.1

[PATCH v8 3/3] iio: proximity: Add driver support for TYHX's HX9023S capacitive proximity sensor

[Yasin Lee]

A SAR sensor from NanjingTianyihexin Electronics Ltd.

The device has the following entry points:

Usual frequency:
- sampling_frequency

Instant reading of current values for different sensors:
- in_proximity0_raw
- in_proximity1_raw
- in_proximity2_raw
- in_proximity3_raw
- in_proximity4_raw
and associated events in events/

Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>
---
 drivers/iio/proximity/Kconfig   |   14 +
 drivers/iio/proximity/Makefile  |    1 +
 drivers/iio/proximity/hx9023s.c | 1131 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 1146 insertions(+)

diff --git a/drivers/iio/proximity/Kconfig b/drivers/iio/proximity/Kconfig
index 2ca3b0bc5eba..0694f625b432 100644
--- a/drivers/iio/proximity/Kconfig
+++ b/drivers/iio/proximity/Kconfig
@@ -32,6 +32,20 @@ config CROS_EC_MKBP_PROXIMITY
 	  To compile this driver as a module, choose M here: the
 	  module will be called cros_ec_mkbp_proximity.
 
+config HX9023S
+	tristate "TYHX HX9023S SAR sensor"
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	select REGMAP_I2C
+	depends on I2C
+	help
+	  Say Y here to build a driver for TYHX HX9023S capacitive SAR sensor.
+	  This driver supports the TYHX HX9023S capacitive
+	  SAR sensors. This sensors is used for proximity detection applications.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called hx9023s.
+
 config IRSD200
 	tristate "Murata IRS-D200 PIR sensor"
 	select IIO_BUFFER
diff --git a/drivers/iio/proximity/Makefile b/drivers/iio/proximity/Makefile
index f36598380446..ab381cd27dbb 100644
--- a/drivers/iio/proximity/Makefile
+++ b/drivers/iio/proximity/Makefile
@@ -6,6 +6,7 @@
 # When adding new entries keep the list in alphabetical order
 obj-$(CONFIG_AS3935)		+= as3935.o
 obj-$(CONFIG_CROS_EC_MKBP_PROXIMITY) += cros_ec_mkbp_proximity.o
+obj-$(CONFIG_HX9023S)		+= hx9023s.o
 obj-$(CONFIG_IRSD200)		+= irsd200.o
 obj-$(CONFIG_ISL29501)		+= isl29501.o
 obj-$(CONFIG_LIDAR_LITE_V2)	+= pulsedlight-lidar-lite-v2.o
diff --git a/drivers/iio/proximity/hx9023s.c b/drivers/iio/proximity/hx9023s.c
new file mode 100644
index 000000000000..c455f20d784f
--- /dev/null
+++ b/drivers/iio/proximity/hx9023s.c
@@ -0,0 +1,1131 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2024 NanjingTianyihexin Electronics Ltd.
+ * http://www.tianyihexin.com
+ *
+ * Driver for NanjingTianyihexin HX9023S Cap Sensor.
+ * Datasheet available at:
+ * http://www.tianyihexin.com/ueditor/php/upload/file/20240614/1718336303992081.pdf
+ */
+
+#include <linux/array_size.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/cleanup.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/math64.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/pm.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/types.h>
+#include <linux/units.h>
+
+#include <asm/byteorder.h>
+#include <asm/unaligned.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/events.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/types.h>
+
+#define HX9023S_CHIP_ID 0x1D
+#define HX9023S_CH_NUM 5
+#define HX9023S_2BYTES 2
+#define HX9023S_3BYTES 3
+#define HX9023S_BYTES_MAX HX9023S_3BYTES
+#define HX9023S_POS 0x03
+#define HX9023S_NEG 0x02
+#define HX9023S_NOT_CONNECTED 16
+
+#define HX9023S_GLOBAL_CTRL0                   0x00
+#define HX9023S_PRF_CFG                        0x02
+#define HX9023S_CH0_CFG_7_0                    0x03
+#define HX9023S_CH4_CFG_9_8                    0x0C
+#define HX9023S_RANGE_7_0                      0x0D
+#define HX9023S_RANGE_9_8                      0x0E
+#define HX9023S_RANGE_18_16                    0x0F
+#define HX9023S_AVG0_NOSR0_CFG                 0x10
+#define HX9023S_NOSR12_CFG                     0x11
+#define HX9023S_NOSR34_CFG                     0x12
+#define HX9023S_AVG12_CFG                      0x13
+#define HX9023S_AVG34_CFG                      0x14
+#define HX9023S_OFFSET_DAC0_7_0                0x15
+#define HX9023S_OFFSET_DAC4_9_8                0x1E
+#define HX9023S_SAMPLE_NUM_7_0                 0x1F
+#define HX9023S_INTEGRATION_NUM_7_0            0x21
+#define HX9023S_CH_NUM_CFG                     0x24
+#define HX9023S_LP_ALP_4_CFG                   0x29
+#define HX9023S_LP_ALP_1_0_CFG                 0x2A
+#define HX9023S_LP_ALP_3_2_CFG                 0x2B
+#define HX9023S_UP_ALP_1_0_CFG                 0x2C
+#define HX9023S_UP_ALP_3_2_CFG                 0x2D
+#define HX9023S_DN_UP_ALP_0_4_CFG              0x2E
+#define HX9023S_DN_ALP_2_1_CFG                 0x2F
+#define HX9023S_DN_ALP_4_3_CFG                 0x30
+#define HX9023S_RAW_BL_RD_CFG                  0x38
+#define HX9023S_INTERRUPT_CFG                  0x39
+#define HX9023S_INTERRUPT_CFG1                 0x3A
+#define HX9023S_CALI_DIFF_CFG                  0x3B
+#define HX9023S_DITHER_CFG                     0x3C
+#define HX9023S_DEVICE_ID                      0x60
+#define HX9023S_PROX_STATUS                    0x6B
+#define HX9023S_PROX_INT_HIGH_CFG              0x6C
+#define HX9023S_PROX_INT_LOW_CFG               0x6D
+#define HX9023S_PROX_HIGH_DIFF_CFG_CH0_0       0x80
+#define HX9023S_PROX_LOW_DIFF_CFG_CH0_0        0x88
+#define HX9023S_PROX_LOW_DIFF_CFG_CH3_1        0x8F
+#define HX9023S_PROX_HIGH_DIFF_CFG_CH4_0       0x9E
+#define HX9023S_PROX_HIGH_DIFF_CFG_CH4_1       0x9F
+#define HX9023S_PROX_LOW_DIFF_CFG_CH4_0        0xA2
+#define HX9023S_PROX_LOW_DIFF_CFG_CH4_1        0xA3
+#define HX9023S_CAP_INI_CH4_0                  0xB3
+#define HX9023S_LP_DIFF_CH4_2                  0xBA
+#define HX9023S_RAW_BL_CH4_0                   0xB5
+#define HX9023S_LP_DIFF_CH4_0                  0xB8
+#define HX9023S_DSP_CONFIG_CTRL1               0xC8
+#define HX9023S_CAP_INI_CH0_0                  0xE0
+#define HX9023S_RAW_BL_CH0_0                   0xE8
+#define HX9023S_LP_DIFF_CH0_0                  0xF4
+#define HX9023S_LP_DIFF_CH3_2                  0xFF
+
+#define HX9023S_DATA_LOCK_MASK BIT(4)
+#define HX9023S_INTERRUPT_MASK GENMASK(9, 0)
+#define HX9023S_PROX_DEBOUNCE_MASK GENMASK(3, 0)
+
+struct hx9023s_ch_data {
+	int raw; /* Raw Data*/
+	int lp; /* Low Pass Filter Data*/
+	int bl; /* Base Line Data */
+	int diff; /* difference of Low Pass Data and Base Line Data */
+
+	struct {
+		unsigned int near;
+		unsigned int far;
+	} thres;
+
+	u16 dac;
+	u8 channel_positive;
+	u8 channel_negative;
+	bool sel_bl;
+	bool sel_raw;
+	bool sel_diff;
+	bool sel_lp;
+	bool enable;
+};
+
+struct hx9023s_data {
+	struct iio_trigger *trig;
+	struct regmap *regmap;
+	unsigned long chan_prox_stat;
+	unsigned long chan_read;
+	unsigned long chan_event;
+	unsigned long ch_en_stat;
+	unsigned long chan_in_use;
+	unsigned int prox_state_reg;
+	bool trigger_enabled;
+
+	struct {
+		__le16 channels[HX9023S_CH_NUM];
+		s64 ts __aligned(8);
+	} buffer;
+
+	/*
+	 * Serialize access to registers below:
+	 * HX9023S_PROX_INT_LOW_CFG,
+	 * HX9023S_PROX_INT_HIGH_CFG,
+	 * HX9023S_INTERRUPT_CFG,
+	 * HX9023S_CH_NUM_CFG
+	 * Serialize access to channel configuration in
+	 * hx9023s_push_events and hx9023s_trigger_handler.
+	 */
+	struct mutex mutex;
+	struct hx9023s_ch_data ch_data[HX9023S_CH_NUM];
+};
+
+static const struct reg_sequence hx9023s_reg_init_list[] = {
+	/* scan period */
+	REG_SEQ0(HX9023S_PRF_CFG, 0x17),
+
+	/* full scale of conversion phase of each channel */
+	REG_SEQ0(HX9023S_RANGE_7_0, 0x11),
+	REG_SEQ0(HX9023S_RANGE_9_8, 0x02),
+	REG_SEQ0(HX9023S_RANGE_18_16, 0x00),
+
+	/* ADC average number and OSR number of each channel */
+	REG_SEQ0(HX9023S_AVG0_NOSR0_CFG, 0x71),
+	REG_SEQ0(HX9023S_NOSR12_CFG, 0x44),
+	REG_SEQ0(HX9023S_NOSR34_CFG, 0x00),
+	REG_SEQ0(HX9023S_AVG12_CFG, 0x33),
+	REG_SEQ0(HX9023S_AVG34_CFG, 0x00),
+
+	/* sample & integration frequency of the ADC */
+	REG_SEQ0(HX9023S_SAMPLE_NUM_7_0, 0x65),
+	REG_SEQ0(HX9023S_INTEGRATION_NUM_7_0, 0x65),
+
+	/* coefficient of the first order low pass filter during each channel */
+	REG_SEQ0(HX9023S_LP_ALP_1_0_CFG, 0x22),
+	REG_SEQ0(HX9023S_LP_ALP_3_2_CFG, 0x22),
+	REG_SEQ0(HX9023S_LP_ALP_4_CFG, 0x02),
+
+	/* up coefficient of the first order low pass filter during each channel */
+	REG_SEQ0(HX9023S_UP_ALP_1_0_CFG, 0x88),
+	REG_SEQ0(HX9023S_UP_ALP_3_2_CFG, 0x88),
+	REG_SEQ0(HX9023S_DN_UP_ALP_0_4_CFG, 0x18),
+
+	/* down coefficient of the first order low pass filter during each channel */
+	REG_SEQ0(HX9023S_DN_ALP_2_1_CFG, 0x11),
+	REG_SEQ0(HX9023S_DN_ALP_4_3_CFG, 0x11),
+
+	/* selection of data for the Data Mux Register to output data */
+	REG_SEQ0(HX9023S_RAW_BL_RD_CFG, 0xF0),
+
+	/* enable the interrupt function */
+	REG_SEQ0(HX9023S_INTERRUPT_CFG, 0xFF),
+	REG_SEQ0(HX9023S_INTERRUPT_CFG1, 0x3B),
+	REG_SEQ0(HX9023S_DITHER_CFG, 0x21),
+
+	/* threshold of the offset compensation */
+	REG_SEQ0(HX9023S_CALI_DIFF_CFG, 0x07),
+
+	/* proximity persistency number(near & far) */
+	REG_SEQ0(HX9023S_PROX_INT_HIGH_CFG, 0x01),
+	REG_SEQ0(HX9023S_PROX_INT_LOW_CFG, 0x01),
+
+	/* disable the data lock */
+	REG_SEQ0(HX9023S_DSP_CONFIG_CTRL1, 0x00),
+};
+
+static const struct iio_event_spec hx9023s_events[] = {
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_RISING,
+		.mask_shared_by_all = BIT(IIO_EV_INFO_PERIOD),
+		.mask_separate = BIT(IIO_EV_INFO_VALUE),
+	},
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_FALLING,
+		.mask_shared_by_all = BIT(IIO_EV_INFO_PERIOD),
+		.mask_separate = BIT(IIO_EV_INFO_VALUE),
+
+	},
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_EITHER,
+		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
+	},
+};
+
+#define HX9023S_CHANNEL(idx)					\
+{								\
+	.type = IIO_PROXIMITY,					\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
+	.indexed = 1,						\
+	.channel = idx,						\
+	.address = 0,						\
+	.event_spec = hx9023s_events,				\
+	.num_event_specs = ARRAY_SIZE(hx9023s_events),		\
+	.scan_index = idx,					\
+	.scan_type = {						\
+		.sign = 's',					\
+		.realbits = 16,					\
+		.storagebits = 16,				\
+		.endianness = IIO_BE,				\
+	},							\
+}
+
+static const struct iio_chan_spec hx9023s_channels[] = {
+	HX9023S_CHANNEL(0),
+	HX9023S_CHANNEL(1),
+	HX9023S_CHANNEL(2),
+	HX9023S_CHANNEL(3),
+	HX9023S_CHANNEL(4),
+	IIO_CHAN_SOFT_TIMESTAMP(5),
+};
+
+static const unsigned int hx9023s_samp_freq_table[] = {
+	2, 2, 4, 6, 8, 10, 14, 18, 22, 26,
+	30, 34, 38, 42, 46, 50, 56, 62, 68, 74,
+	80, 90, 100, 200, 300, 400, 600, 800, 1000, 2000,
+	3000, 4000,
+};
+
+static const struct regmap_range hx9023s_rd_reg_ranges[] = {
+	regmap_reg_range(HX9023S_GLOBAL_CTRL0, HX9023S_LP_DIFF_CH3_2),
+};
+
+static const struct regmap_range hx9023s_wr_reg_ranges[] = {
+	regmap_reg_range(HX9023S_GLOBAL_CTRL0, HX9023S_LP_DIFF_CH3_2),
+};
+
+static const struct regmap_range hx9023s_volatile_reg_ranges[] = {
+	regmap_reg_range(HX9023S_CAP_INI_CH4_0, HX9023S_LP_DIFF_CH4_2),
+	regmap_reg_range(HX9023S_CAP_INI_CH0_0, HX9023S_LP_DIFF_CH3_2),
+	regmap_reg_range(HX9023S_PROX_STATUS, HX9023S_PROX_STATUS),
+};
+
+static const struct regmap_access_table hx9023s_rd_regs = {
+	.yes_ranges = hx9023s_rd_reg_ranges,
+	.n_yes_ranges = ARRAY_SIZE(hx9023s_rd_reg_ranges),
+};
+
+static const struct regmap_access_table hx9023s_wr_regs = {
+	.yes_ranges = hx9023s_wr_reg_ranges,
+	.n_yes_ranges = ARRAY_SIZE(hx9023s_wr_reg_ranges),
+};
+
+static const struct regmap_access_table hx9023s_volatile_regs = {
+	.yes_ranges = hx9023s_volatile_reg_ranges,
+	.n_yes_ranges = ARRAY_SIZE(hx9023s_volatile_reg_ranges),
+};
+
+static const struct regmap_config hx9023s_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.cache_type = REGCACHE_MAPLE,
+	.rd_table = &hx9023s_rd_regs,
+	.wr_table = &hx9023s_wr_regs,
+	.volatile_table = &hx9023s_volatile_regs,
+};
+
+static int hx9023s_interrupt_enable(struct hx9023s_data *data)
+{
+	return regmap_update_bits(data->regmap, HX9023S_INTERRUPT_CFG,
+				HX9023S_INTERRUPT_MASK, HX9023S_INTERRUPT_MASK);
+}
+
+static int hx9023s_interrupt_disable(struct hx9023s_data *data)
+{
+	return regmap_update_bits(data->regmap, HX9023S_INTERRUPT_CFG,
+				HX9023S_INTERRUPT_MASK, 0x00);
+}
+
+static int hx9023s_data_lock(struct hx9023s_data *data, bool locked)
+{
+	if (locked)
+		return regmap_update_bits(data->regmap, HX9023S_DSP_CONFIG_CTRL1,
+					HX9023S_DATA_LOCK_MASK, HX9023S_DATA_LOCK_MASK);
+	else
+		return regmap_update_bits(data->regmap, HX9023S_DSP_CONFIG_CTRL1,
+					HX9023S_DATA_LOCK_MASK, 0);
+}
+
+static int hx9023s_ch_cfg(struct hx9023s_data *data)
+{
+	unsigned int i;
+	u16 reg;
+	u8 reg_list[HX9023S_CH_NUM * 2];
+	u8 ch_pos[HX9023S_CH_NUM];
+	u8 ch_neg[HX9023S_CH_NUM];
+	/* Bit positions corresponding to input pin connections */
+	u8 conn_cs[HX9023S_CH_NUM] = {0, 2, 4, 6, 8};
+
+	for (i = 0; i < HX9023S_CH_NUM; i++) {
+		ch_pos[i] = data->ch_data[i].channel_positive == HX9023S_NOT_CONNECTED ?
+			HX9023S_NOT_CONNECTED : conn_cs[data->ch_data[i].channel_positive];
+		ch_neg[i] = data->ch_data[i].channel_negative == HX9023S_NOT_CONNECTED ?
+			HX9023S_NOT_CONNECTED : conn_cs[data->ch_data[i].channel_negative];
+
+		reg = (HX9023S_POS << ch_pos[i]) | (HX9023S_NEG << ch_neg[i]);
+		put_unaligned_le16(reg, &reg_list[i * 2]);
+	}
+
+	return regmap_bulk_write(data->regmap, HX9023S_CH0_CFG_7_0, reg_list, HX9023S_CH_NUM * 2);
+}
+
+static int hx9023s_write_far_debounce(struct hx9023s_data *data, int val)
+{
+	guard(mutex)(&data->mutex);
+	return regmap_update_bits(data->regmap, HX9023S_PROX_INT_LOW_CFG,
+				HX9023S_PROX_DEBOUNCE_MASK,
+				FIELD_GET(HX9023S_PROX_DEBOUNCE_MASK, val));
+}
+
+static int hx9023s_write_near_debounce(struct hx9023s_data *data, int val)
+{
+	guard(mutex)(&data->mutex);
+	return regmap_update_bits(data->regmap, HX9023S_PROX_INT_HIGH_CFG,
+				HX9023S_PROX_DEBOUNCE_MASK,
+				FIELD_GET(HX9023S_PROX_DEBOUNCE_MASK, val));
+}
+
+static int hx9023s_read_far_debounce(struct hx9023s_data *data, int *val)
+{
+	int ret;
+
+	ret = regmap_read(data->regmap, HX9023S_PROX_INT_LOW_CFG, val);
+	if (ret)
+		return ret;
+
+	*val = FIELD_GET(HX9023S_PROX_DEBOUNCE_MASK, *val);
+
+	return IIO_VAL_INT;
+}
+
+static int hx9023s_read_near_debounce(struct hx9023s_data *data, int *val)
+{
+	int ret;
+
+	ret = regmap_read(data->regmap, HX9023S_PROX_INT_HIGH_CFG, val);
+	if (ret)
+		return ret;
+
+	*val = FIELD_GET(HX9023S_PROX_DEBOUNCE_MASK, *val);
+
+	return IIO_VAL_INT;
+}
+
+static int hx9023s_get_thres_near(struct hx9023s_data *data, u8 ch, int *val)
+{
+	int ret;
+	u8 buf[2];
+	unsigned int reg, tmp;
+
+	reg = (ch == 4) ? HX9023S_PROX_HIGH_DIFF_CFG_CH4_0 :
+		HX9023S_PROX_HIGH_DIFF_CFG_CH0_0 + (ch * HX9023S_2BYTES);
+
+	ret = regmap_bulk_read(data->regmap, reg, buf, sizeof(buf));
+	if (ret)
+		return ret;
+
+	tmp = (get_unaligned_le16(buf) & GENMASK(9, 0)) * 32;
+	data->ch_data[ch].thres.near = tmp;
+	*val = tmp;
+
+	return IIO_VAL_INT;
+}
+
+static int hx9023s_get_thres_far(struct hx9023s_data *data, u8 ch, int *val)
+{
+	int ret;
+	u8 buf[2];
+	unsigned int reg, tmp;
+
+	reg = (ch == 4) ? HX9023S_PROX_LOW_DIFF_CFG_CH4_0 :
+		HX9023S_PROX_LOW_DIFF_CFG_CH0_0 + (ch * HX9023S_2BYTES);
+
+	ret = regmap_bulk_read(data->regmap, reg, buf, sizeof(buf));
+	if (ret)
+		return ret;
+
+	tmp = (get_unaligned_le16(buf) & GENMASK(9, 0)) * 32;
+	data->ch_data[ch].thres.far = tmp;
+	*val = tmp;
+
+	return IIO_VAL_INT;
+}
+
+static int hx9023s_set_thres_near(struct hx9023s_data *data, u8 ch, int val)
+{
+	__le16 val_le16 = cpu_to_le16((val / 32) & GENMASK(9, 0));
+	unsigned int reg;
+
+	data->ch_data[ch].thres.near = ((val / 32) & GENMASK(9, 0)) * 32;
+	reg = (ch == 4) ? HX9023S_PROX_HIGH_DIFF_CFG_CH4_0 :
+		HX9023S_PROX_HIGH_DIFF_CFG_CH0_0 + (ch * HX9023S_2BYTES);
+
+	return regmap_bulk_write(data->regmap, reg, &val_le16, sizeof(val_le16));
+}
+
+static int hx9023s_set_thres_far(struct hx9023s_data *data, u8 ch, int val)
+{
+	__le16 val_le16 = cpu_to_le16((val / 32) & GENMASK(9, 0));
+	unsigned int reg;
+
+	data->ch_data[ch].thres.far = ((val / 32) & GENMASK(9, 0)) * 32;
+	reg = (ch == 4) ? HX9023S_PROX_LOW_DIFF_CFG_CH4_0 :
+		HX9023S_PROX_LOW_DIFF_CFG_CH0_0 + (ch * HX9023S_2BYTES);
+
+	return regmap_bulk_write(data->regmap, reg, &val_le16, sizeof(val_le16));
+}
+
+static int hx9023s_get_prox_state(struct hx9023s_data *data)
+{
+	return regmap_read(data->regmap, HX9023S_PROX_STATUS, &data->prox_state_reg);
+}
+
+static int hx9023s_data_select(struct hx9023s_data *data)
+{
+	int ret;
+	unsigned int i, buf;
+	unsigned long tmp;
+
+	ret = regmap_read(data->regmap, HX9023S_RAW_BL_RD_CFG, &buf);
+	if (ret)
+		return ret;
+
+	tmp = buf;
+	for (i = 0; i < 4; i++) {
+		data->ch_data[i].sel_diff = test_bit(i, &tmp);
+		data->ch_data[i].sel_lp = !data->ch_data[i].sel_diff;
+		data->ch_data[i].sel_bl = test_bit(i + 4, &tmp);
+		data->ch_data[i].sel_raw = !data->ch_data[i].sel_bl;
+	}
+
+	ret = regmap_read(data->regmap, HX9023S_INTERRUPT_CFG1, &buf);
+	if (ret)
+		return ret;
+
+	tmp = buf;
+	data->ch_data[4].sel_diff = test_bit(2, &tmp);
+	data->ch_data[4].sel_lp = !data->ch_data[4].sel_diff;
+	data->ch_data[4].sel_bl = test_bit(3, &tmp);
+	data->ch_data[4].sel_raw = !data->ch_data[4].sel_bl;
+
+	return 0;
+}
+
+static int hx9023s_sample(struct hx9023s_data *data)
+{
+	int ret, value;
+	unsigned int i;
+	u8 data_size, offset_data_size, *p, size, rx_buf[HX9023S_CH_NUM * HX9023S_BYTES_MAX];
+
+	ret = hx9023s_data_lock(data, true);
+	if (ret)
+		return ret;
+
+	ret = hx9023s_data_select(data);
+	if (ret)
+		goto err;
+
+	data_size = HX9023S_3BYTES;
+
+	/* ch0~ch3 */
+	p = rx_buf;
+	size = (HX9023S_CH_NUM - 1) * data_size;
+	ret = regmap_bulk_read(data->regmap, HX9023S_RAW_BL_CH0_0, p, size);
+	if (ret)
+		goto err;
+
+	/* ch4 */
+	p = rx_buf + size;
+	size = data_size;
+	ret = regmap_bulk_read(data->regmap, HX9023S_RAW_BL_CH4_0, p, size);
+	if (ret)
+		goto err;
+
+	for (i = 0; i < HX9023S_CH_NUM; i++) {
+		value = get_unaligned_le16(&rx_buf[i * data_size + 1]);
+		value = sign_extend32(value, 15);
+		data->ch_data[i].raw = 0;
+		data->ch_data[i].bl = 0;
+		if (data->ch_data[i].sel_raw)
+			data->ch_data[i].raw = value;
+		if (data->ch_data[i].sel_bl)
+			data->ch_data[i].bl = value;
+	}
+
+	/* ch0~ch3 */
+	p = rx_buf;
+	size = (HX9023S_CH_NUM - 1) * data_size;
+	ret = regmap_bulk_read(data->regmap, HX9023S_LP_DIFF_CH0_0, p, size);
+	if (ret)
+		goto err;
+
+	/* ch4 */
+	p = rx_buf + size;
+	size = data_size;
+	ret = regmap_bulk_read(data->regmap, HX9023S_LP_DIFF_CH4_0, p, size);
+	if (ret)
+		goto err;
+
+	for (i = 0; i < HX9023S_CH_NUM; i++) {
+		value = get_unaligned_le16(&rx_buf[i * data_size + 1]);
+		value = sign_extend32(value, 15);
+		data->ch_data[i].lp = 0;
+		data->ch_data[i].diff = 0;
+		if (data->ch_data[i].sel_lp)
+			data->ch_data[i].lp = value;
+		if (data->ch_data[i].sel_diff)
+			data->ch_data[i].diff = value;
+	}
+
+	for (i = 0; i < HX9023S_CH_NUM; i++) {
+		if (data->ch_data[i].sel_lp && data->ch_data[i].sel_bl)
+			data->ch_data[i].diff = data->ch_data[i].lp - data->ch_data[i].bl;
+	}
+
+	/* offset DAC */
+	offset_data_size = HX9023S_2BYTES;
+	p = rx_buf;
+	size = HX9023S_CH_NUM * offset_data_size;
+	ret = regmap_bulk_read(data->regmap, HX9023S_OFFSET_DAC0_7_0, p, size);
+	if (ret)
+		goto err;
+
+	for (i = 0; i < HX9023S_CH_NUM; i++) {
+		value = get_unaligned_le16(&rx_buf[i * offset_data_size]);
+		value = FIELD_GET(GENMASK(11, 0), value);
+		data->ch_data[i].dac = value;
+	}
+
+err:
+	return hx9023s_data_lock(data, false);
+}
+
+static int hx9023s_ch_en(struct hx9023s_data *data, u8 ch_id, bool en)
+{
+	int ret;
+	unsigned int buf;
+
+	ret = regmap_read(data->regmap, HX9023S_CH_NUM_CFG, &buf);
+	if (ret)
+		return ret;
+
+	data->ch_en_stat = buf;
+	if (en && data->ch_en_stat == 0)
+		data->prox_state_reg = 0;
+
+	data->ch_data[ch_id].enable = en;
+	__assign_bit(ch_id, &data->ch_en_stat, en);
+
+	return regmap_write(data->regmap, HX9023S_CH_NUM_CFG, data->ch_en_stat);
+}
+
+static int hx9023s_property_get(struct hx9023s_data *data)
+{
+	struct fwnode_handle *child;
+	struct device *dev = regmap_get_device(data->regmap);
+	int ret;
+	u32 i, reg, temp, array[2];
+
+	data->chan_in_use = 0;
+	for (i = 0; i < HX9023S_CH_NUM; i++) {
+		data->ch_data[i].channel_positive = HX9023S_NOT_CONNECTED;
+		data->ch_data[i].channel_negative = HX9023S_NOT_CONNECTED;
+	}
+
+	device_for_each_child_node(dev, child) {
+		ret = fwnode_property_read_u32(child, "reg", &reg);
+		if (ret || reg >= HX9023S_CH_NUM) {
+			fwnode_handle_put(child);
+			return dev_err_probe(dev, ret, "Failed to read reg\n");
+		}
+		__set_bit(reg, &data->chan_in_use);
+
+		if (fwnode_property_read_u32(child, "input-channel", &temp) == 0) {
+			data->ch_data[reg].channel_positive = temp;
+			data->ch_data[reg].channel_negative = HX9023S_NOT_CONNECTED;
+		} else if (fwnode_property_read_u32_array(child, "diff-channels",
+							array, sizeof(array)) == 0) {
+			data->ch_data[reg].channel_positive = array[0];
+			data->ch_data[reg].channel_negative = array[1];
+		} else {
+			fwnode_handle_put(child);
+			return dev_err_probe(dev, ret,
+				"Failed to read channel input for channel %d\n", reg);
+		}
+	}
+
+	return 0;
+}
+
+static int hx9023s_update_chan_en(struct hx9023s_data *data,
+				  unsigned long chan_read,
+				  unsigned long chan_event)
+{
+	unsigned int i;
+	unsigned long channels = chan_read | chan_event;
+
+	if ((data->chan_read | data->chan_event) != channels) {
+		for_each_set_bit(i, &channels, HX9023S_CH_NUM)
+			hx9023s_ch_en(data, i, test_bit(i, &data->chan_in_use));
+		for_each_clear_bit(i, &channels, HX9023S_CH_NUM)
+			hx9023s_ch_en(data, i, false);
+	}
+
+	data->chan_read = chan_read;
+	data->chan_event = chan_event;
+
+	return 0;
+}
+
+static int hx9023s_get_proximity(struct hx9023s_data *data,
+				 const struct iio_chan_spec *chan,
+				 int *val)
+{
+	int ret;
+
+	ret = hx9023s_sample(data);
+	if (ret)
+		return ret;
+
+	ret = hx9023s_get_prox_state(data);
+	if (ret)
+		return ret;
+
+	*val = data->ch_data[chan->channel].diff;
+	return IIO_VAL_INT;
+}
+
+static int hx9023s_get_samp_freq(struct hx9023s_data *data, int *val, int *val2)
+{
+	int ret;
+	unsigned int odr, index;
+
+	ret = regmap_read(data->regmap, HX9023S_PRF_CFG, &index);
+	if (ret)
+		return ret;
+
+	odr = hx9023s_samp_freq_table[index];
+	*val = KILO / odr;
+	*val2 = div_u64((KILO % odr) * MICRO, odr);
+
+	return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int hx9023s_read_raw(struct iio_dev *indio_dev, const struct iio_chan_spec *chan,
+			    int *val, int *val2, long mask)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+	int ret;
+
+	if (chan->type != IIO_PROXIMITY)
+		return -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			return ret;
+
+		ret = hx9023s_get_proximity(data, chan, val);
+		iio_device_release_direct_mode(indio_dev);
+		return ret;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		return hx9023s_get_samp_freq(data, val, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int hx9023s_set_samp_freq(struct hx9023s_data *data, int val, int val2)
+{
+	struct device *dev = regmap_get_device(data->regmap);
+	unsigned int i, period_ms;
+
+	period_ms = div_u64(NANO, (val * MEGA + val2));
+
+	for (i = 0; i < ARRAY_SIZE(hx9023s_samp_freq_table); i++) {
+		if (period_ms == hx9023s_samp_freq_table[i])
+			break;
+	}
+	if (i == ARRAY_SIZE(hx9023s_samp_freq_table)) {
+		dev_err(dev, "Period:%dms NOT found!\n", period_ms);
+		return -EINVAL;
+	}
+
+	return regmap_write(data->regmap, HX9023S_PRF_CFG, i);
+}
+
+static int hx9023s_write_raw(struct iio_dev *indio_dev, const struct iio_chan_spec *chan,
+			     int val, int val2, long mask)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+
+	if (chan->type != IIO_PROXIMITY)
+		return -EINVAL;
+
+	if (mask != IIO_CHAN_INFO_SAMP_FREQ)
+		return -EINVAL;
+
+	return hx9023s_set_samp_freq(data, val, val2);
+}
+
+static irqreturn_t hx9023s_irq_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct hx9023s_data *data = iio_priv(indio_dev);
+
+	if (data->trigger_enabled)
+		iio_trigger_poll(data->trig);
+
+	return IRQ_WAKE_THREAD;
+}
+
+static void hx9023s_push_events(struct iio_dev *indio_dev)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+	s64 timestamp = iio_get_time_ns(indio_dev);
+	unsigned long prox_changed;
+	unsigned int chan;
+
+	hx9023s_sample(data);
+	hx9023s_get_prox_state(data);
+
+	prox_changed = (data->chan_prox_stat ^ data->prox_state_reg) & data->chan_event;
+	for_each_set_bit(chan, &prox_changed, HX9023S_CH_NUM) {
+		unsigned int dir;
+
+		dir = (data->prox_state_reg & BIT(chan)) ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
+
+		iio_push_event(indio_dev,
+			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan, IIO_EV_TYPE_THRESH, dir),
+			       timestamp);
+	}
+	data->chan_prox_stat = data->prox_state_reg;
+}
+
+static irqreturn_t hx9023s_irq_thread_handler(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct hx9023s_data *data = iio_priv(indio_dev);
+
+	guard(mutex)(&data->mutex);
+	hx9023s_push_events(indio_dev);
+
+	return IRQ_HANDLED;
+}
+
+static int hx9023s_read_event_val(struct iio_dev *indio_dev,
+				  const struct iio_chan_spec *chan,
+				  enum iio_event_type type,
+				  enum iio_event_direction dir,
+				  enum iio_event_info info, int *val, int *val2)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+
+	if (chan->type != IIO_PROXIMITY)
+		return -EINVAL;
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			return hx9023s_get_thres_far(data, chan->channel, val);
+		case IIO_EV_DIR_FALLING:
+			return hx9023s_get_thres_near(data, chan->channel, val);
+		default:
+			return -EINVAL;
+		}
+	case IIO_EV_INFO_PERIOD:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			return hx9023s_read_far_debounce(data, val);
+		case IIO_EV_DIR_FALLING:
+			return hx9023s_read_near_debounce(data, val);
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+static int hx9023s_write_event_val(struct iio_dev *indio_dev,
+				   const struct iio_chan_spec *chan,
+				   enum iio_event_type type,
+				   enum iio_event_direction dir,
+				   enum iio_event_info info, int val, int val2)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+
+	if (chan->type != IIO_PROXIMITY)
+		return -EINVAL;
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			return hx9023s_set_thres_far(data, chan->channel, val);
+		case IIO_EV_DIR_FALLING:
+			return hx9023s_set_thres_near(data, chan->channel, val);
+		default:
+			return -EINVAL;
+		}
+	case IIO_EV_INFO_PERIOD:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			return hx9023s_write_far_debounce(data, val);
+		case IIO_EV_DIR_FALLING:
+			return hx9023s_write_near_debounce(data, val);
+		default:
+			return -EINVAL;
+		}
+	default:
+		return -EINVAL;
+	}
+}
+
+static int hx9023s_read_event_config(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+
+	return test_bit(chan->channel, &data->chan_event);
+}
+
+static int hx9023s_write_event_config(struct iio_dev *indio_dev,
+				      const struct iio_chan_spec *chan,
+				      enum iio_event_type type,
+				      enum iio_event_direction dir,
+				      int state)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+
+	if (test_bit(chan->channel, &data->chan_in_use)) {
+		hx9023s_ch_en(data, chan->channel, !!state);
+		__assign_bit(chan->channel, &data->chan_event, data->ch_data[chan->channel].enable);
+	}
+
+	return 0;
+}
+
+static const struct iio_info hx9023s_info = {
+	.read_raw = hx9023s_read_raw,
+	.write_raw = hx9023s_write_raw,
+	.read_event_value = hx9023s_read_event_val,
+	.write_event_value = hx9023s_write_event_val,
+	.read_event_config = hx9023s_read_event_config,
+	.write_event_config = hx9023s_write_event_config,
+};
+
+static int hx9023s_set_trigger_state(struct iio_trigger *trig, bool state)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	struct hx9023s_data *data = iio_priv(indio_dev);
+
+	guard(mutex)(&data->mutex);
+	if (state)
+		hx9023s_interrupt_enable(data);
+	else if (!data->chan_read)
+		hx9023s_interrupt_disable(data);
+	data->trigger_enabled = state;
+
+	return 0;
+}
+
+static const struct iio_trigger_ops hx9023s_trigger_ops = {
+	.set_trigger_state = hx9023s_set_trigger_state,
+};
+
+static irqreturn_t hx9023s_trigger_handler(int irq, void *private)
+{
+	struct iio_poll_func *pf = private;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct hx9023s_data *data = iio_priv(indio_dev);
+	struct device *dev = regmap_get_device(data->regmap);
+	int ret;
+	unsigned int bit, index, i = 0;
+
+	guard(mutex)(&data->mutex);
+	ret = hx9023s_sample(data);
+	if (ret) {
+		dev_warn(dev, "sampling failed\n");
+		goto out;
+	}
+
+	ret = hx9023s_get_prox_state(data);
+	if (ret) {
+		dev_warn(dev, "get prox failed\n");
+		goto out;
+	}
+
+	for_each_set_bit(bit, indio_dev->active_scan_mask, indio_dev->masklength) {
+		index = indio_dev->channels[bit].channel;
+		data->buffer.channels[i++] = cpu_to_le16(data->ch_data[index].diff);
+	}
+
+	iio_push_to_buffers_with_timestamp(indio_dev, &data->buffer, pf->timestamp);
+
+out:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static int hx9023s_buffer_preenable(struct iio_dev *indio_dev)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+	unsigned long channels = 0;
+	unsigned int bit;
+
+	guard(mutex)(&data->mutex);
+	for_each_set_bit(bit, indio_dev->active_scan_mask, indio_dev->masklength)
+		__set_bit(indio_dev->channels[bit].channel, &channels);
+
+	hx9023s_update_chan_en(data, channels, data->chan_event);
+
+	return 0;
+}
+
+static int hx9023s_buffer_postdisable(struct iio_dev *indio_dev)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+
+	guard(mutex)(&data->mutex);
+	hx9023s_update_chan_en(data, 0, data->chan_event);
+
+	return 0;
+}
+
+static const struct iio_buffer_setup_ops hx9023s_buffer_setup_ops = {
+	.preenable = hx9023s_buffer_preenable,
+	.postdisable = hx9023s_buffer_postdisable,
+};
+
+static int hx9023s_id_check(struct iio_dev *indio_dev)
+{
+	struct hx9023s_data *data = iio_priv(indio_dev);
+	int ret;
+	unsigned int id;
+
+	ret = regmap_read(data->regmap, HX9023S_DEVICE_ID, &id);
+	if (ret || id != HX9023S_CHIP_ID)
+		return -ENODEV;
+
+	return 0;
+}
+
+static int hx9023s_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct iio_dev *indio_dev;
+	struct hx9023s_data *data;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(struct hx9023s_data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	mutex_init(&data->mutex);
+
+	data->regmap = devm_regmap_init_i2c(client, &hx9023s_regmap_config);
+	if (IS_ERR(data->regmap))
+		return dev_err_probe(dev, PTR_ERR(data->regmap), "regmap init failed\n");
+
+	ret = hx9023s_property_get(data);
+	if (ret)
+		return dev_err_probe(dev, ret, "dts phase failed\n");
+
+	ret = devm_regulator_get_enable(dev, "vdd");
+	if (ret)
+		return dev_err_probe(dev, ret, "regulator get failed\n");
+
+	ret = hx9023s_id_check(indio_dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "id check failed\n");
+
+	indio_dev->name = "hx9023s";
+	indio_dev->channels = hx9023s_channels;
+	indio_dev->num_channels = ARRAY_SIZE(hx9023s_channels);
+	indio_dev->info = &hx9023s_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	i2c_set_clientdata(client, indio_dev);
+
+	ret = regmap_multi_reg_write(data->regmap, hx9023s_reg_init_list,
+				     ARRAY_SIZE(hx9023s_reg_init_list));
+	if (ret)
+		return dev_err_probe(dev, ret, "device init failed\n");
+
+	ret = hx9023s_ch_cfg(data);
+	if (ret)
+		return dev_err_probe(dev, ret, "channel config failed\n");
+
+	ret = regcache_sync(data->regmap);
+	if (ret)
+		return dev_err_probe(dev, ret, "regcache sync failed\n");
+
+	if (client->irq) {
+		ret = devm_request_threaded_irq(dev, client->irq, hx9023s_irq_handler,
+						hx9023s_irq_thread_handler, IRQF_ONESHOT,
+						"hx9023s_event", indio_dev);
+		if (ret)
+			return dev_err_probe(dev, ret, "irq request failed\n");
+
+		data->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name,
+						    iio_device_id(indio_dev));
+		if (!data->trig)
+			return dev_err_probe(dev, -ENOMEM,
+					"iio trigger alloc failed\n");
+
+		data->trig->ops = &hx9023s_trigger_ops;
+		iio_trigger_set_drvdata(data->trig, indio_dev);
+
+		ret = devm_iio_trigger_register(dev, data->trig);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					"iio trigger register failed\n");
+	}
+
+	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, iio_pollfunc_store_time,
+					      hx9023s_trigger_handler, &hx9023s_buffer_setup_ops);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				"iio triggered buffer setup failed\n");
+
+	return devm_iio_device_register(dev, indio_dev);
+}
+
+static int hx9023s_suspend(struct device *dev)
+{
+	struct hx9023s_data *data = iio_priv(dev_get_drvdata(dev));
+
+	guard(mutex)(&data->mutex);
+	hx9023s_interrupt_disable(data);
+
+	return 0;
+}
+
+static int hx9023s_resume(struct device *dev)
+{
+	struct hx9023s_data *data = iio_priv(dev_get_drvdata(dev));
+
+	guard(mutex)(&data->mutex);
+	if (data->trigger_enabled)
+		hx9023s_interrupt_enable(data);
+
+	return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(hx9023s_pm_ops, hx9023s_suspend, hx9023s_resume);
+
+static const struct of_device_id hx9023s_of_match[] = {
+	{ .compatible = "tyhx,hx9023s" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, hx9023s_of_match);
+
+static const struct i2c_device_id hx9023s_id[] = {
+	{ "hx9023s" },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, hx9023s_id);
+
+static struct i2c_driver hx9023s_driver = {
+	.driver = {
+		.name = "hx9023s",
+		.of_match_table = hx9023s_of_match,
+		.pm = &hx9023s_pm_ops,
+
+		/*
+		 * The I2C operations in hx9023s_reg_init() and hx9023s_ch_cfg()
+		 * are time-consuming. Prefer async so we don't delay boot
+		 * if we're builtin to the kernel.
+		 */
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+	},
+	.probe = hx9023s_probe,
+	.id_table = hx9023s_id,
+};
+module_i2c_driver(hx9023s_driver);
+
+MODULE_AUTHOR("Yasin Lee <yasin.lee.x@gmail.com>");
+MODULE_DESCRIPTION("Driver for TYHX HX9023S SAR sensor");
+MODULE_LICENSE("GPL");

-- 
2.25.1

Re: [PATCH v8 2/3] dt-bindings: iio: proximity: Add TYHX HX9023S

[Rob Herring (Arm)]

On Tue, 25 Jun 2024 23:58:53 +0800, Yasin Lee wrote:
> A capacitive proximity sensor
> 
> Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>
> ---
>  .../bindings/iio/proximity/tyhx,hx9023s.yaml       | 93 ++++++++++++++++++++++
>  1 file changed, 93 insertions(+)
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/iio/proximity/tyhx,hx9023s.example.dtb: proximity@2a: channel@0: Unevaluated properties are not allowed ('single-channel' was unexpected)
	from schema $id: http://devicetree.org/schemas/iio/proximity/tyhx,hx9023s.yaml#
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/iio/proximity/tyhx,hx9023s.example.dtb: proximity@2a: channel@1: Unevaluated properties are not allowed ('single-channel' was unexpected)
	from schema $id: http://devicetree.org/schemas/iio/proximity/tyhx,hx9023s.yaml#
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/iio/proximity/tyhx,hx9023s.example.dtb: proximity@2a: channel@2: Unevaluated properties are not allowed ('single-channel' was unexpected)
	from schema $id: http://devicetree.org/schemas/iio/proximity/tyhx,hx9023s.yaml#

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20240625-add-tyhx-hx9023s-sensor-driver-v8-2-0c224e3bddbc@gmail.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

Re: [PATCH v8 2/3] dt-bindings: iio: proximity: Add TYHX HX9023S

[Krzysztof Kozlowski]

On 25/06/2024 17:58, Yasin Lee wrote:
> A capacitive proximity sensor
> 
> Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>


Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>


---

<form letter>
This is an automated instruction, just in case, because many review tags
are being ignored. If you know the process, you can skip it (please do
not feel offended by me posting it here - no bad intentions intended).
If you do not know the process, here is a short explanation:

Please add Acked-by/Reviewed-by/Tested-by tags when posting new
versions, under or above your Signed-off-by tag. Tag is "received", when
provided in a message replied to you on the mailing list. Tools like b4
can help here. However, there's no need to repost patches *only* to add
the tags. The upstream maintainer will do that for tags received on the
version they apply.

https://elixir.bootlin.com/linux/v6.5-rc3/source/Documentation/process/submitting-patches.rst#L577
</form letter>

This should be clear:
*Tag is "received", when provided in a message replied to you on the
mailing list.*

Best regards,
Krzysztof

Re: [PATCH v8 2/3] dt-bindings: iio: proximity: Add TYHX HX9023S

[Yasin Lee]

On 2024/6/26 16:34, Krzysztof Kozlowski wrote:
> On 25/06/2024 17:58, Yasin Lee wrote:
>> A capacitive proximity sensor
>>
>> Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>
>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>
>
> ---
>
> <form letter>
> This is an automated instruction, just in case, because many review tags
> are being ignored. If you know the process, you can skip it (please do
> not feel offended by me posting it here - no bad intentions intended).
> If you do not know the process, here is a short explanation:
>
> Please add Acked-by/Reviewed-by/Tested-by tags when posting new
> versions, under or above your Signed-off-by tag. Tag is "received", when
> provided in a message replied to you on the mailing list. Tools like b4
> can help here. However, there's no need to repost patches *only* to add
> the tags. The upstream maintainer will do that for tags received on the
> version they apply.
>
> https://elixir.bootlin.com/linux/v6.5-rc3/source/Documentation/process/submitting-patches.rst#L577
> </form letter>
>
> This should be clear:
> *Tag is "received", when provided in a message replied to you on the
> mailing list.*
>
> Best regards,
> Krzysztof

Hi Krzysztof,

Thank you very much for your review and guidance.

I understand now when to add tags like Acked-by, Reviewed-by, and 
Tested-by when posting new versions.

Best regards,

Yasin

Re: [PATCH v8 3/3] iio: proximity: Add driver support for TYHX's HX9023S capacitive proximity sensor

[Jonathan Cameron]

On Tue, 25 Jun 2024 23:58:54 +0800
Yasin Lee <yasin.lee.x@gmail.com> wrote:

> A SAR sensor from NanjingTianyihexin Electronics Ltd.
> 
> The device has the following entry points:
> 
> Usual frequency:
> - sampling_frequency
> 
> Instant reading of current values for different sensors:
> - in_proximity0_raw
> - in_proximity1_raw
> - in_proximity2_raw
> - in_proximity3_raw
> - in_proximity4_raw
> and associated events in events/
> 
> Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>
Hi Yasin

Definitely getting close to ready to merge.
A few bits of review feedback inline to resolve.

Jonathan

> diff --git a/drivers/iio/proximity/hx9023s.c b/drivers/iio/proximity/hx9023s.c
> new file mode 100644
> index 000000000000..c455f20d784f
> --- /dev/null
> +++ b/drivers/iio/proximity/hx9023s.c
> @@ -0,0 +1,1131 @@

> +
> +#define HX9023S_CHIP_ID 0x1D
> +#define HX9023S_CH_NUM 5
> +#define HX9023S_2BYTES 2
> +#define HX9023S_3BYTES 3

Don't use defines where the number is actually more meaningful
when seen in the code.

> +#define HX9023S_BYTES_MAX HX9023S_3BYTES
This define is useful but just make it 3.

> +struct hx9023s_ch_data {
> +	int raw; /* Raw Data*/
> +	int lp; /* Low Pass Filter Data*/
> +	int bl; /* Base Line Data */
> +	int diff; /* difference of Low Pass Data and Base Line Data */
Difference

for consistency of capitalizaton.


> +static int hx9023s_ch_cfg(struct hx9023s_data *data)
> +{
> +	unsigned int i;
> +	u16 reg;
> +	u8 reg_list[HX9023S_CH_NUM * 2];
> +	u8 ch_pos[HX9023S_CH_NUM];
> +	u8 ch_neg[HX9023S_CH_NUM];
> +	/* Bit positions corresponding to input pin connections */
> +	u8 conn_cs[HX9023S_CH_NUM] = {0, 2, 4, 6, 8};

Space after { and before }

> +
> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
> +		ch_pos[i] = data->ch_data[i].channel_positive == HX9023S_NOT_CONNECTED ?
> +			HX9023S_NOT_CONNECTED : conn_cs[data->ch_data[i].channel_positive];
> +		ch_neg[i] = data->ch_data[i].channel_negative == HX9023S_NOT_CONNECTED ?
> +			HX9023S_NOT_CONNECTED : conn_cs[data->ch_data[i].channel_negative];
> +
> +		reg = (HX9023S_POS << ch_pos[i]) | (HX9023S_NEG << ch_neg[i]);
> +		put_unaligned_le16(reg, &reg_list[i * 2]);
> +	}
> +
> +	return regmap_bulk_write(data->regmap, HX9023S_CH0_CFG_7_0, reg_list, HX9023S_CH_NUM * 2);
> +}

> +
> +static int hx9023s_sample(struct hx9023s_data *data)
> +{
> +	int ret, value;
> +	unsigned int i;
> +	u8 data_size, offset_data_size, *p, size, rx_buf[HX9023S_CH_NUM * HX9023S_BYTES_MAX];

Long line combining different data types. Break them up to improve readability.

	u8 rx_buf[HX9023S_CH_NUM * HX9023S_BYTES_MAX];
	u8 data_size, offset_data_size, size;
	u8 *p;

> +
> +	ret = hx9023s_data_lock(data, true);
> +	if (ret)
> +		return ret;
> +
> +	ret = hx9023s_data_select(data);
> +	if (ret)
> +		goto err;
> +
> +	data_size = HX9023S_3BYTES;
This local variable hurts readabilty.
> +
> +	/* ch0~ch3 */
> +	p = rx_buf;
Why local variable?
> +	size = (HX9023S_CH_NUM - 1) * data_size;

This is non obvious sizing.  Here a comment is appropriate.

/* 3 bytes for each of channels 0 to 3 which have contiguous registers */

> +	ret = regmap_bulk_read(data->regmap, HX9023S_RAW_BL_CH0_0, p, size);

Combining above comments.

	ret = regmap_bulk_read(data->regmap, HX9023S_RAW_BL_CH0_0, &rx_buf, size);

> +	if (ret)
> +		goto err;
> +
> +	/* ch4 */
> +	p = rx_buf + size;
> +	size = data_size;
Here as well provide a comment on the fact the channel is 3 contiguous registers.


> +	ret = regmap_bulk_read(data->regmap, HX9023S_RAW_BL_CH4_0, p, size);
> +	if (ret)
> +		goto err;
> +
> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
> +		value = get_unaligned_le16(&rx_buf[i * data_size + 1]);
This seems odd.  From the datasheet I found seems there are some bits in
the ch0_0 register as well. Why just pull out 16 bits?

I would use a get_unaligned_le24() call to get the rest and then rely on
shift for userspace to drop bits 3:0

It it makes sense to just provide the top 16 bits thats fine.
> +		value = sign_extend32(value, 15);

Why use int to store an s16?  If you just use an s16 for value then no
need to sign extend and then store that into an s16 .raw in the channel
data structure.

> +		data->ch_data[i].raw = 0;
> +		data->ch_data[i].bl = 0;
> +		if (data->ch_data[i].sel_raw)
> +			data->ch_data[i].raw = value;
> +		if (data->ch_data[i].sel_bl)
> +			data->ch_data[i].bl = value;
> +	}
> +
> +	/* ch0~ch3 */
> +	p = rx_buf;
> +	size = (HX9023S_CH_NUM - 1) * data_size;
As above - use a comment to explain why this is 12 then just use 12.
Current form is far form obvious.

> +	ret = regmap_bulk_read(data->regmap, HX9023S_LP_DIFF_CH0_0, p, size);
> +	if (ret)
> +		goto err;
> +
> +	/* ch4 */
> +	p = rx_buf + size;
> +	size = data_size;
> +	ret = regmap_bulk_read(data->regmap, HX9023S_LP_DIFF_CH4_0, p, size);
> +	if (ret)
> +		goto err;
> +
> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
> +		value = get_unaligned_le16(&rx_buf[i * data_size + 1]);
> +		value = sign_extend32(value, 15);
> +		data->ch_data[i].lp = 0;
> +		data->ch_data[i].diff = 0;
> +		if (data->ch_data[i].sel_lp)
> +			data->ch_data[i].lp = value;
> +		if (data->ch_data[i].sel_diff)
> +			data->ch_data[i].diff = value;
> +	}
> +
> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
> +		if (data->ch_data[i].sel_lp && data->ch_data[i].sel_bl)
> +			data->ch_data[i].diff = data->ch_data[i].lp - data->ch_data[i].bl;
> +	}
> +
> +	/* offset DAC */
> +	offset_data_size = HX9023S_2BYTES;
> +	p = rx_buf;
> +	size = HX9023S_CH_NUM * offset_data_size;
> +	ret = regmap_bulk_read(data->regmap, HX9023S_OFFSET_DAC0_7_0, p, size);
> +	if (ret)
> +		goto err;
> +
> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
> +		value = get_unaligned_le16(&rx_buf[i * offset_data_size]);
> +		value = FIELD_GET(GENMASK(11, 0), value);
> +		data->ch_data[i].dac = value;
> +	}
> +
> +err:
> +	return hx9023s_data_lock(data, false);
> +}


> +
> +static int hx9023s_property_get(struct hx9023s_data *data)
> +{
> +	struct fwnode_handle *child;
> +	struct device *dev = regmap_get_device(data->regmap);
> +	int ret;
> +	u32 i, reg, temp, array[2];
> +
> +	data->chan_in_use = 0;
> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
> +		data->ch_data[i].channel_positive = HX9023S_NOT_CONNECTED;
> +		data->ch_data[i].channel_negative = HX9023S_NOT_CONNECTED;
> +	}
> +
> +	device_for_each_child_node(dev, child) {

Use
	device_for_each_child_node_scoped(dev, child) {
As then no need to call fwnode_handle_put() in error paths.

> +		ret = fwnode_property_read_u32(child, "reg", &reg);
> +		if (ret || reg >= HX9023S_CH_NUM) {
> +			fwnode_handle_put(child);
> +			return dev_err_probe(dev, ret, "Failed to read reg\n");
> +		}
> +		__set_bit(reg, &data->chan_in_use);
> +
> +		if (fwnode_property_read_u32(child, "input-channel", &temp) == 0) {
> +			data->ch_data[reg].channel_positive = temp;
> +			data->ch_data[reg].channel_negative = HX9023S_NOT_CONNECTED;
> +		} else if (fwnode_property_read_u32_array(child, "diff-channels",
> +							array, sizeof(array)) == 0) {
> +			data->ch_data[reg].channel_positive = array[0];
> +			data->ch_data[reg].channel_negative = array[1];
> +		} else {
> +			fwnode_handle_put(child);
> +			return dev_err_probe(dev, ret,
> +				"Failed to read channel input for channel %d\n", reg);
> +		}
> +	}
> +
> +	return 0;
> +}


> +
> +static void hx9023s_push_events(struct iio_dev *indio_dev)
> +{
> +	struct hx9023s_data *data = iio_priv(indio_dev);
> +	s64 timestamp = iio_get_time_ns(indio_dev);
> +	unsigned long prox_changed;
> +	unsigned int chan;
> +
> +	hx9023s_sample(data);

check the return codes for these calls that involve bus transactions.
If they fail, just return form this function having not pushed an event.

Otherwise we may push stale data.

> +	hx9023s_get_prox_state(data);
> +
> +	prox_changed = (data->chan_prox_stat ^ data->prox_state_reg) & data->chan_event;
> +	for_each_set_bit(chan, &prox_changed, HX9023S_CH_NUM) {
> +		unsigned int dir;
> +
> +		dir = (data->prox_state_reg & BIT(chan)) ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
> +
> +		iio_push_event(indio_dev,
> +			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan, IIO_EV_TYPE_THRESH, dir),
> +			       timestamp);
> +	}
> +	data->chan_prox_stat = data->prox_state_reg;
> +}






> +static int hx9023s_id_check(struct iio_dev *indio_dev)
> +{
> +	struct hx9023s_data *data = iio_priv(indio_dev);
> +	int ret;
> +	unsigned int id;
> +
> +	ret = regmap_read(data->regmap, HX9023S_DEVICE_ID, &id);
> +	if (ret || id != HX9023S_CHIP_ID)
> +		return -ENODEV;
This breaks the use of callback compatible IDs in future. It is only
appropriate to print a warning on an unknown ID .
Also don't eat the error value returned - it may provide a useful hint
of a problem.

	if (ret)
		return ret;

	if (id != HX9023S_CHIP_ID)
		dev_warn(&indio_dev->dev.parent,
			 "Unexpected chip ID, assuming compatible\n");

	return 0;

there are lots of older drivers where we did this wrong. We tend to
repair this when otherwise working on a driver, so it will take a
while before they are all fixed.


> +
> +	return 0;
> +}
> +
> +static int hx9023s_probe(struct i2c_client *client)
> +{
> +	struct device *dev = &client->dev;
> +	struct iio_dev *indio_dev;
> +	struct hx9023s_data *data;
> +	int ret;
> +
> +	indio_dev = devm_iio_device_alloc(dev, sizeof(struct hx9023s_data));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	data = iio_priv(indio_dev);
> +	mutex_init(&data->mutex);
> +
> +	data->regmap = devm_regmap_init_i2c(client, &hx9023s_regmap_config);
> +	if (IS_ERR(data->regmap))
> +		return dev_err_probe(dev, PTR_ERR(data->regmap), "regmap init failed\n");
> +
> +	ret = hx9023s_property_get(data);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "dts phase failed\n");
> +
> +	ret = devm_regulator_get_enable(dev, "vdd");
> +	if (ret)
> +		return dev_err_probe(dev, ret, "regulator get failed\n");
> +
> +	ret = hx9023s_id_check(indio_dev);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "id check failed\n");

As commented on above, this should not fail on a missmatch ont he ID, just
on a failure to read it at all.  That enables future devices that haven't
been made yet and happen to be compatible to be able to work with older
linux kernels that predate them.


> +}

Re: [PATCH v8 3/3] iio: proximity: Add driver support for TYHX's HX9023S capacitive proximity sensor

[Yasin Lee]

On 2024/6/30 02:41, Jonathan Cameron wrote:
> On Tue, 25 Jun 2024 23:58:54 +0800
> Yasin Lee <yasin.lee.x@gmail.com> wrote:
>
>> A SAR sensor from NanjingTianyihexin Electronics Ltd.
>>
>> The device has the following entry points:
>>
>> Usual frequency:
>> - sampling_frequency
>>
>> Instant reading of current values for different sensors:
>> - in_proximity0_raw
>> - in_proximity1_raw
>> - in_proximity2_raw
>> - in_proximity3_raw
>> - in_proximity4_raw
>> and associated events in events/
>>
>> Signed-off-by: Yasin Lee <yasin.lee.x@gmail.com>
> Hi Yasin
>
> Definitely getting close to ready to merge.
> A few bits of review feedback inline to resolve.
>
> Jonathan
>

Hi Jonathan,


Thank you very much for your patient guidance and encouragement. I have 
made modifications and responses to each comment. Please review version V9.

Best regards,

Yasin


>> diff --git a/drivers/iio/proximity/hx9023s.c b/drivers/iio/proximity/hx9023s.c
>> new file mode 100644
>> index 000000000000..c455f20d784f
>> --- /dev/null
>> +++ b/drivers/iio/proximity/hx9023s.c
>> @@ -0,0 +1,1131 @@
>> +
>> +#define HX9023S_CHIP_ID 0x1D
>> +#define HX9023S_CH_NUM 5
>> +#define HX9023S_2BYTES 2
>> +#define HX9023S_3BYTES 3
> Don't use defines where the number is actually more meaningful
> when seen in the code.
>
>> +#define HX9023S_BYTES_MAX HX9023S_3BYTES
> This define is useful but just make it 3.
>

These three macro definitions will be deleted in version V9.


>> +struct hx9023s_ch_data {
>> +	int raw; /* Raw Data*/
>> +	int lp; /* Low Pass Filter Data*/
>> +	int bl; /* Base Line Data */
>> +	int diff; /* difference of Low Pass Data and Base Line Data */
> Difference
>
> for consistency of capitalizaton.
>

Fixed in v9.


>> +static int hx9023s_ch_cfg(struct hx9023s_data *data)
>> +{
>> +	unsigned int i;
>> +	u16 reg;
>> +	u8 reg_list[HX9023S_CH_NUM * 2];
>> +	u8 ch_pos[HX9023S_CH_NUM];
>> +	u8 ch_neg[HX9023S_CH_NUM];
>> +	/* Bit positions corresponding to input pin connections */
>> +	u8 conn_cs[HX9023S_CH_NUM] = {0, 2, 4, 6, 8};
> Space after { and before }


Fixed in v9.


>> +
>> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
>> +		ch_pos[i] = data->ch_data[i].channel_positive == HX9023S_NOT_CONNECTED ?
>> +			HX9023S_NOT_CONNECTED : conn_cs[data->ch_data[i].channel_positive];
>> +		ch_neg[i] = data->ch_data[i].channel_negative == HX9023S_NOT_CONNECTED ?
>> +			HX9023S_NOT_CONNECTED : conn_cs[data->ch_data[i].channel_negative];
>> +
>> +		reg = (HX9023S_POS << ch_pos[i]) | (HX9023S_NEG << ch_neg[i]);
>> +		put_unaligned_le16(reg, &reg_list[i * 2]);
>> +	}
>> +
>> +	return regmap_bulk_write(data->regmap, HX9023S_CH0_CFG_7_0, reg_list, HX9023S_CH_NUM * 2);
>> +}
>> +
>> +static int hx9023s_sample(struct hx9023s_data *data)
>> +{
>> +	int ret, value;
>> +	unsigned int i;
>> +	u8 data_size, offset_data_size, *p, size, rx_buf[HX9023S_CH_NUM * HX9023S_BYTES_MAX];
> Long line combining different data types. Break them up to improve readability.
>
> 	u8 rx_buf[HX9023S_CH_NUM * HX9023S_BYTES_MAX];
> 	u8 data_size, offset_data_size, size;
> 	u8 *p;


Delete: data_size, offset_data_size, *p, size.


>> +
>> +	ret = hx9023s_data_lock(data, true);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = hx9023s_data_select(data);
>> +	if (ret)
>> +		goto err;
>> +
>> +	data_size = HX9023S_3BYTES;
> This local variable hurts readabilty.


Deleted.


>> +
>> +	/* ch0~ch3 */
>> +	p = rx_buf;
> Why local variable?


Deleted.


>> +	size = (HX9023S_CH_NUM - 1) * data_size;
> This is non obvious sizing.  Here a comment is appropriate.
>
> /* 3 bytes for each of channels 0 to 3 which have contiguous registers */
>
>> +	ret = regmap_bulk_read(data->regmap, HX9023S_RAW_BL_CH0_0, p, size);
> Combining above comments.
>
> 	ret = regmap_bulk_read(data->regmap, HX9023S_RAW_BL_CH0_0, &rx_buf, size);
>
>> +	if (ret)
>> +		goto err;
>> +
>> +	/* ch4 */
>> +	p = rx_buf + size;
>> +	size = data_size;
> Here as well provide a comment on the fact the channel is 3 contiguous registers.
>

Added concise comments as suggested, deleted excessive macro 
definitions, and used direct numbers for clarity.


>> +	ret = regmap_bulk_read(data->regmap, HX9023S_RAW_BL_CH4_0, p, size);
>> +	if (ret)
>> +		goto err;
>> +
>> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
>> +		value = get_unaligned_le16(&rx_buf[i * data_size + 1]);
> This seems odd.  From the datasheet I found seems there are some bits in
> the ch0_0 register as well. Why just pull out 16 bits?
>
> I would use a get_unaligned_le24() call to get the rest and then rely on
> shift for userspace to drop bits 3:0
>
> It it makes sense to just provide the top 16 bits thats fine.


Based on the chip designer's explanation, the lower 8-bit data is almost 
meaningless, and users are advised to use only the upper 16-bit data. 
Therefore, I kept get_unaligned_le16().


>> +		value = sign_extend32(value, 15);
> Why use int to store an s16?  If you just use an s16 for value then no
> need to sign extend and then store that into an s16 .raw in the channel
> data structure.
>

Using int is incorrect. I will take your advice, delete sign_extend32, 
and directly store the data in s16.


>> +		data->ch_data[i].raw = 0;
>> +		data->ch_data[i].bl = 0;
>> +		if (data->ch_data[i].sel_raw)
>> +			data->ch_data[i].raw = value;
>> +		if (data->ch_data[i].sel_bl)
>> +			data->ch_data[i].bl = value;
>> +	}
>> +
>> +	/* ch0~ch3 */
>> +	p = rx_buf;
>> +	size = (HX9023S_CH_NUM - 1) * data_size;
> As above - use a comment to explain why this is 12 then just use 12.
> Current form is far form obvious.


I will take this suggestion and update it in V9.


>> +	ret = regmap_bulk_read(data->regmap, HX9023S_LP_DIFF_CH0_0, p, size);
>> +	if (ret)
>> +		goto err;
>> +
>> +	/* ch4 */
>> +	p = rx_buf + size;
>> +	size = data_size;
>> +	ret = regmap_bulk_read(data->regmap, HX9023S_LP_DIFF_CH4_0, p, size);
>> +	if (ret)
>> +		goto err;
>> +
>> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
>> +		value = get_unaligned_le16(&rx_buf[i * data_size + 1]);
>> +		value = sign_extend32(value, 15);
>> +		data->ch_data[i].lp = 0;
>> +		data->ch_data[i].diff = 0;
>> +		if (data->ch_data[i].sel_lp)
>> +			data->ch_data[i].lp = value;
>> +		if (data->ch_data[i].sel_diff)
>> +			data->ch_data[i].diff = value;
>> +	}
>> +
>> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
>> +		if (data->ch_data[i].sel_lp && data->ch_data[i].sel_bl)
>> +			data->ch_data[i].diff = data->ch_data[i].lp - data->ch_data[i].bl;
>> +	}
>> +
>> +	/* offset DAC */
>> +	offset_data_size = HX9023S_2BYTES;
>> +	p = rx_buf;
>> +	size = HX9023S_CH_NUM * offset_data_size;
>> +	ret = regmap_bulk_read(data->regmap, HX9023S_OFFSET_DAC0_7_0, p, size);
>> +	if (ret)
>> +		goto err;
>> +
>> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
>> +		value = get_unaligned_le16(&rx_buf[i * offset_data_size]);
>> +		value = FIELD_GET(GENMASK(11, 0), value);
>> +		data->ch_data[i].dac = value;
>> +	}
>> +
>> +err:
>> +	return hx9023s_data_lock(data, false);
>> +}
>
>> +
>> +static int hx9023s_property_get(struct hx9023s_data *data)
>> +{
>> +	struct fwnode_handle *child;
>> +	struct device *dev = regmap_get_device(data->regmap);
>> +	int ret;
>> +	u32 i, reg, temp, array[2];
>> +
>> +	data->chan_in_use = 0;
>> +	for (i = 0; i < HX9023S_CH_NUM; i++) {
>> +		data->ch_data[i].channel_positive = HX9023S_NOT_CONNECTED;
>> +		data->ch_data[i].channel_negative = HX9023S_NOT_CONNECTED;
>> +	}
>> +
>> +	device_for_each_child_node(dev, child) {
> Use
> 	device_for_each_child_node_scoped(dev, child) {
> As then no need to call fwnode_handle_put() in error paths.


I will take this suggestion and update it in V9.


>> +		ret = fwnode_property_read_u32(child, "reg", &reg);
>> +		if (ret || reg >= HX9023S_CH_NUM) {
>> +			fwnode_handle_put(child);
>> +			return dev_err_probe(dev, ret, "Failed to read reg\n");
>> +		}
>> +		__set_bit(reg, &data->chan_in_use);
>> +
>> +		if (fwnode_property_read_u32(child, "input-channel", &temp) == 0) {
>> +			data->ch_data[reg].channel_positive = temp;
>> +			data->ch_data[reg].channel_negative = HX9023S_NOT_CONNECTED;
>> +		} else if (fwnode_property_read_u32_array(child, "diff-channels",
>> +							array, sizeof(array)) == 0) {
>> +			data->ch_data[reg].channel_positive = array[0];
>> +			data->ch_data[reg].channel_negative = array[1];
>> +		} else {
>> +			fwnode_handle_put(child);
>> +			return dev_err_probe(dev, ret,
>> +				"Failed to read channel input for channel %d\n", reg);
>> +		}
>> +	}
>> +
>> +	return 0;
>> +}
>
>> +
>> +static void hx9023s_push_events(struct iio_dev *indio_dev)
>> +{
>> +	struct hx9023s_data *data = iio_priv(indio_dev);
>> +	s64 timestamp = iio_get_time_ns(indio_dev);
>> +	unsigned long prox_changed;
>> +	unsigned int chan;
>> +
>> +	hx9023s_sample(data);
> check the return codes for these calls that involve bus transactions.
> If they fail, just return form this function having not pushed an event.
>
> Otherwise we may push stale data.


Fixed in v9


>> +	hx9023s_get_prox_state(data);
>> +
>> +	prox_changed = (data->chan_prox_stat ^ data->prox_state_reg) & data->chan_event;
>> +	for_each_set_bit(chan, &prox_changed, HX9023S_CH_NUM) {
>> +		unsigned int dir;
>> +
>> +		dir = (data->prox_state_reg & BIT(chan)) ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
>> +
>> +		iio_push_event(indio_dev,
>> +			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan, IIO_EV_TYPE_THRESH, dir),
>> +			       timestamp);
>> +	}
>> +	data->chan_prox_stat = data->prox_state_reg;
>> +}
>
>
>
>
>
>> +static int hx9023s_id_check(struct iio_dev *indio_dev)
>> +{
>> +	struct hx9023s_data *data = iio_priv(indio_dev);
>> +	int ret;
>> +	unsigned int id;
>> +
>> +	ret = regmap_read(data->regmap, HX9023S_DEVICE_ID, &id);
>> +	if (ret || id != HX9023S_CHIP_ID)
>> +		return -ENODEV;
> This breaks the use of callback compatible IDs in future. It is only
> appropriate to print a warning on an unknown ID .
> Also don't eat the error value returned - it may provide a useful hint
> of a problem.
>
> 	if (ret)
> 		return ret;
>
> 	if (id != HX9023S_CHIP_ID)
> 		dev_warn(&indio_dev->dev.parent,
> 			 "Unexpected chip ID, assuming compatible\n");
>
> 	return 0;
>
> there are lots of older drivers where we did this wrong. We tend to
> repair this when otherwise working on a driver, so it will take a
> while before they are all fixed.
>

I will take this suggestion and update it in V9.


>> +
>> +	return 0;
>> +}
>> +
>> +static int hx9023s_probe(struct i2c_client *client)
>> +{
>> +	struct device *dev = &client->dev;
>> +	struct iio_dev *indio_dev;
>> +	struct hx9023s_data *data;
>> +	int ret;
>> +
>> +	indio_dev = devm_iio_device_alloc(dev, sizeof(struct hx9023s_data));
>> +	if (!indio_dev)
>> +		return -ENOMEM;
>> +
>> +	data = iio_priv(indio_dev);
>> +	mutex_init(&data->mutex);
>> +
>> +	data->regmap = devm_regmap_init_i2c(client, &hx9023s_regmap_config);
>> +	if (IS_ERR(data->regmap))
>> +		return dev_err_probe(dev, PTR_ERR(data->regmap), "regmap init failed\n");
>> +
>> +	ret = hx9023s_property_get(data);
>> +	if (ret)
>> +		return dev_err_probe(dev, ret, "dts phase failed\n");
>> +
>> +	ret = devm_regulator_get_enable(dev, "vdd");
>> +	if (ret)
>> +		return dev_err_probe(dev, ret, "regulator get failed\n");
>> +
>> +	ret = hx9023s_id_check(indio_dev);
>> +	if (ret)
>> +		return dev_err_probe(dev, ret, "id check failed\n");
> As commented on above, this should not fail on a missmatch ont he ID, just
> on a failure to read it at all.  That enables future devices that haven't
> been made yet and happen to be compatible to be able to work with older
> linux kernels that predate them.
>

Understood, thank you very much for your detailed explanation.


>> +}