From: Enrico Granata <egran...@chromium.org>

This driver allows interfacing with the Semtech sx9320, sx9321 and sx9324
proximity sensors via the IIO subsystem.

Signed-off-by: Enrico Granata <egran...@chromium.org>
---
 .../bindings/iio/proximity/sx932x.txt         |   54 +
 drivers/iio/proximity/Kconfig                 |   36 +-
 drivers/iio/proximity/Makefile                |    1 +
 drivers/iio/proximity/sx932x.c                | 1462 +++++++++++++++++
 4 files changed, 1542 insertions(+), 11 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/iio/proximity/sx932x.txt
 create mode 100644 drivers/iio/proximity/sx932x.c

diff --git a/Documentation/devicetree/bindings/iio/proximity/sx932x.txt 
b/Documentation/devicetree/bindings/iio/proximity/sx932x.txt
new file mode 100644
index 0000000000000..e1f1fefdbca08
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/proximity/sx932x.txt
@@ -0,0 +1,54 @@
+Semtech's SX9320/SX9321/SX9324 capacitive proximity button device driver
+
+Required properties:
+       - compatible: must be "semtech,sx9320 or sx9321 or sx9324"
+       - reg: i2c address where to find the device
+       - interrupt-parent : should be the phandle for the interrupt controller
+       - interrupts : the sole interrupt generated by the device
+       - semtech,register-prefix: the string prefixing all register names in 
the
+
+       Refer to interrupt-controller/interrupts.txt for generic
+       interrupt client node bindings.
+
+Optional properties:
+       - semtech,adv_ctrl10: Initial value for register AdvCtrl10.
+       - semtech,afe_ctrl4: Initial value for register AfeCtrl4.
+       - semtech,afe_ctrl7: Initial value for register AfeCtrl7.
+       - semtech,afe_ctrl9: Initial value for register AfeCtrl9.
+       - semtech,prox_ctrl0: Initial value for register ProxCtrl0.
+       - semtech,prox_ctrl1: Initial value for register ProxCtrl1.
+       - semtech,prox_ctrl2: Initial value for register ProxCtrl2.
+       - semtech,prox_ctrl4: Initial value for register ProxCtrl4.
+       - semtech,prox_ctrl5: Initial value for register ProxCtrl5.
+       - semtech,prox_ctrl6: Initial value for register ProxCtrl6.
+       - semtech,prox_ctrl7: Initial value for register Prox_Trl7.
+       - semtech,adv_ctrl16: Initial value for register AdvCtrl16.
+       - semtech,adv_ctrl17: Initial value for register AdvCtrl17.
+       - semtech,adv_ctrl18: Initial value for register AdvCtrl18.
+       - semtech,gnrl_ctrl1: Initial value for register GnrlCtrl1.
+
+       Refer to the data sheet for register definitions.
+
+Example:
+
+sx9310@28 {
+       compatible = "semtech,sx9320";
+       reg = <0x28>;
+       interrupt-parent = <&gpio2>;
+       interrupts = <16 IRQ_TYPE_LEVEL_LOW>;
+};
+
+Driver supports ACPI bindings. We can store registers configuration obtained
+from per-model SAR sensor calibration. Refer to the data sheet for meaning.
+
+ACPI name is STH9320 or STH9321 or STH9324.
+
+Example:
+    chip drivers/i2c/generic
+            register "hid" = ""STH9321""
+            register "name" = ""SEMTECH SX9321""
+            register "desc" = ""SAR Proximity Sensor""
+            register "irq" = "ACPI_IRQ_LEVEL_LOW(GPP_A18_IRQ)"
+            register "device_present_gpio" = "GPP_B20"
+            device i2c 28 on end
+    end
diff --git a/drivers/iio/proximity/Kconfig b/drivers/iio/proximity/Kconfig
index b99367a89f810..3b979b8198d7c 100644
--- a/drivers/iio/proximity/Kconfig
+++ b/drivers/iio/proximity/Kconfig
@@ -66,31 +66,45 @@ config SRF04
          To compile this driver as a module, choose M here: the
          module will be called srf04.
 
-config SX9500
-       tristate "SX9500 Semtech proximity sensor"
+config SRF08
+       tristate "Devantech SRF02/SRF08/SRF10 ultrasonic ranger sensor"
+       select IIO_BUFFER
+       select IIO_TRIGGERED_BUFFER
+       depends on I2C
+       help
+         Say Y here to build a driver for Devantech SRF02/SRF08/SRF10
+         ultrasonic 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 srf08.
+
+config SX932X
+       tristate "sx932x Semtech proximity sensor"
        select IIO_BUFFER
        select IIO_TRIGGERED_BUFFER
        select REGMAP_I2C
        depends on I2C
        help
-         Say Y here to build a driver for Semtech's SX9500 capacitive
-         proximity/button sensor.
+         Say Y here to build a driver for Semtech's sx932x capacitive
+         proximity/button sensor. This driver supports Semtech's
+         sx9320, sx9321 and sx9324 sensors.
 
          To compile this driver as a module, choose M here: the
-         module will be called sx9500.
+         module will be called sx932x.
 
-config SRF08
-       tristate "Devantech SRF02/SRF08/SRF10 ultrasonic ranger sensor"
+config SX9500
+       tristate "SX9500 Semtech proximity sensor"
        select IIO_BUFFER
        select IIO_TRIGGERED_BUFFER
+       select REGMAP_I2C
        depends on I2C
        help
-         Say Y here to build a driver for Devantech SRF02/SRF08/SRF10
-         ultrasonic ranger sensors with i2c interface.
-         This driver can be used to measure the distance of objects.
+         Say Y here to build a driver for Semtech's SX9500 capacitive
+         proximity/button sensor.
 
          To compile this driver as a module, choose M here: the
-         module will be called srf08.
+         module will be called sx9500.
 
 config VL53L0X_I2C
        tristate "STMicroelectronics VL53L0X ToF ranger sensor (I2C)"
diff --git a/drivers/iio/proximity/Makefile b/drivers/iio/proximity/Makefile
index 6d031f903c4c2..65ac237d63dd6 100644
--- a/drivers/iio/proximity/Makefile
+++ b/drivers/iio/proximity/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_LIDAR_LITE_V2)   += pulsedlight-lidar-lite-v2.o
 obj-$(CONFIG_RFD77402)         += rfd77402.o
 obj-$(CONFIG_SRF04)            += srf04.o
 obj-$(CONFIG_SRF08)            += srf08.o
+obj-$(CONFIG_SX932X)           += sx932x.o
 obj-$(CONFIG_SX9500)           += sx9500.o
 obj-$(CONFIG_VL53L0X_I2C)      += vl53l0x-i2c.o
 
diff --git a/drivers/iio/proximity/sx932x.c b/drivers/iio/proximity/sx932x.c
new file mode 100644
index 0000000000000..069d3678f6bc9
--- /dev/null
+++ b/drivers/iio/proximity/sx932x.c
@@ -0,0 +1,1462 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2018 Google LLC.
+ *
+ * Driver for Semtech's SX9320 capacitive proximity/button solution.
+ * Datasheet available at
+ * <http://www.semtech.com/images/datasheet/sx9320.pdf>.
+ * Based on SX9500 driver and Semtech driver using the input framework
+ * <https://my.syncplicity.com/share/teouwsim8niiaud/
+ *          linux-driver-SX9320_NoSmartHSensing>.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/irq.h>
+#include <linux/acpi.h>
+#include <linux/gpio/consumer.h>
+#include <linux/regmap.h>
+#include <linux/pm.h>
+#include <linux/delay.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+
+#define SX932X_DRIVER_NAME             "sx932x"
+#define SX9320_ACPI_NAME               "STH9320"
+#define SX9321_ACPI_NAME               "STH9321"
+#define SX9324_ACPI_NAME               "STH9324"
+#define SX932X_DEV_NB                  2
+
+#define SX932X_IRQ_NAME                        "sx932x_event"
+
+#define SX932X_GPIO_INT                        "interrupt"
+
+/* Register definitions. */
+#define SX932X_REG_IRQ_SRC             0x00
+#define SX932X_REG_STAT0               0x01
+#define SX932X_REG_STAT1               0x02
+#define SX932X_REG_STAT2               0x03
+#define SX932X_REG_STAT3               0x04
+#define SX932X_REG_IRQ_MSK             0x05
+#define SX932X_REG_IRQ_CFG0            0x06
+#define SX932X_REG_IRQ_CFG2            0x07
+
+#define SX932X_REG_GNRL_CTRL0          0x10
+#define SX932X_REG_GNRL_CTRL1          0x11
+
+#define SX932X_REG_I2C_ADDR            0x14
+#define SX932X_REG_CLK_SPRD            0x15
+
+#define SX932X_REG_AFE_CTRL0           0x20
+#define SX932X_REG_AFE_CTRL1           0x21
+#define SX932X_REG_AFE_CTRL2           0x22
+#define SX932X_REG_AFE_CTRL3           0x23
+#define SX932X_REG_AFE_CTRL4           0x24
+#define SX932X_REG_AFE_CTRL5           0x25
+#define SX932X_REG_AFE_CTRL6           0x26
+#define SX932X_REG_AFE_CTRL7           0x27
+#define SX932X_REG_AFE_PH0             0x28
+#define SX932X_REG_AFE_PH1             0x29
+#define SX932X_REG_AFE_PH2             0x2a
+#define SX932X_REG_AFE_PH3             0x2b
+#define SX932X_REG_AFE_CTRL8           0x2c
+#define SX932X_REG_AFE_CTRL9           0x2d
+
+#define SX932X_REG_PROX_CTRL0          0x30
+#define SX932X_REG_PROX_CTRL1          0x31
+#define SX932X_REG_PROX_CTRL2          0x32
+#define SX932X_REG_PROX_CTRL3          0x33
+#define SX932X_REG_PROX_CTRL4          0x34
+#define SX932X_REG_PROX_CTRL5          0x35
+#define SX932X_REG_PROX_CTRL6          0x36
+#define SX932X_REG_PROX_CTRL7          0x37
+
+#define SX932X_REG_ADV_CTRL0           0x40
+#define SX932X_REG_ADV_CTRL1           0x41
+#define SX932X_REG_ADV_CTRL2           0x42
+#define SX932X_REG_ADV_CTRL3           0x43
+#define SX932X_REG_ADV_CTRL4           0x44
+#define SX932X_REG_ADV_CTRL5           0x45
+#define SX932X_REG_ADV_CTRL6           0x46
+#define SX932X_REG_ADV_CTRL7           0x47
+#define SX932X_REG_ADV_CTRL8           0x48
+#define SX932X_REG_ADV_CTRL9           0x49
+#define SX932X_REG_ADV_CTRL10          0x4a
+#define SX932X_REG_ADV_CTRL11          0x4b
+#define SX932X_REG_ADV_CTRL12          0x4c
+#define SX932X_REG_ADV_CTRL13          0x4d
+#define SX932X_REG_ADV_CTRL14          0x4e
+#define SX932X_REG_ADV_CTRL15          0x4f
+#define SX932X_REG_ADV_CTRL16          0x50
+#define SX932X_REG_ADV_CTRL17          0x51
+#define SX932X_REG_ADV_CTRL18          0x52
+#define SX932X_REG_ADV_CTRL19          0x53
+#define SX932X_REG_ADV_CTRL20          0x54
+
+#define SX932X_REG_PHASE_SEL           0x60
+
+#define SX932X_REG_USE_MSB             0x61
+#define SX932X_REG_USE_LSB             0x62
+
+#define SX932X_REG_AVG_MSB             0x63
+#define SX932X_REG_AVG_LSB             0x64
+
+#define SX932X_REG_DIFF_MSB            0x65
+#define SX932X_REG_DIFF_LSB            0x66
+
+#define SX932X_REG_OFFSET_MSB          0x67
+#define SX932X_REG_OFFSET_LSB          0x68
+
+#define SX932X_REG_SAR_MSB             0x69
+#define SX932X_REG_SAR_LSB             0x6a
+
+#define SX932X_REG_RESET               0x9f
+/* Write this to REG_RESET to do a soft reset. */
+#define SX932X_SOFT_RESET              0xde
+
+#define SX932X_REG_WHOAMI              0xfa
+#define SX9320_WHOAMI                  0x20
+#define SX9321_WHOAMI                  0x21
+#define SX9324_WHOAMI 0x23
+#define SX932X_REG_REVISION            0xfe
+
+
+/* Sensor Readback */
+
+/*
+ * These serve for identifying IRQ source in the IRQ_SRC register, and
+ * also for masking the IRQs in the IRQ_MSK register.
+ */
+#define SX932X_RESET_IRQ               BIT(7)
+#define SX932X_CLOSE_IRQ               BIT(6)
+#define SX932X_FAR_IRQ                 BIT(5)
+#define SX932X_COMPDONE_IRQ            BIT(4)
+#define SX932X_CONVDONE_IRQ            BIT(3)
+
+#define SX932X_SCAN_PERIOD_MASK                GENMASK(7, 4)
+#define SX932X_SCAN_PERIOD_SHIFT       4
+
+#define SX932X_COMPSTAT_MASK           GENMASK(3, 0)
+
+/* 4 channels, as defined in STAT0: PH0, PH1, PH2 and PH3. */
+#define SX932X_NUM_CHANNELS            4
+#define SX932X_CHAN_MASK               GENMASK(1, 0)
+
+struct sx932x_reg_config {
+       const char *property;
+       u8 reg_addr;
+       u8 def_value;
+};
+
+struct sx932x_data {
+       struct mutex mutex;
+       struct i2c_client *client;
+       const struct sx932x_reg_config *reg_config;
+       struct iio_trigger *trig;
+       struct regmap *regmap;
+       /*
+        * Last reading of the proximity status for each channel.
+        * We only send an event to user space when this changes.
+        */
+       bool prox_stat[SX932X_NUM_CHANNELS];
+       bool event_enabled[SX932X_NUM_CHANNELS];
+       bool trigger_enabled;
+       u16 *buffer;
+       /* Remember which phases are enabled during a suspend. */
+       unsigned int suspend_reg_gnrl_ctrl1;
+       struct completion completion;
+       int data_rdy_users, close_far_users;
+       int channel_users[SX932X_NUM_CHANNELS];
+};
+
+static const struct iio_event_spec sx932x_events[] = {
+       {
+               .type = IIO_EV_TYPE_THRESH,
+               .dir = IIO_EV_DIR_EITHER,
+               .mask_separate = BIT(IIO_EV_INFO_ENABLE),
+       },
+};
+
+#define SX932X_RAW_CHANNEL(idx, name, addr)                    \
+       {                                                       \
+               .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 = addr,                                \
+               .event_spec = sx932x_events,                    \
+               .num_event_specs = ARRAY_SIZE(sx932x_events),   \
+               .extend_name = name,                            \
+               .scan_index = idx,                              \
+               .scan_type = {                                  \
+                       .sign = 's',                            \
+                       .realbits = 16,                         \
+                       .storagebits = 16,                      \
+                       .shift = 0,                             \
+               },                                              \
+       }
+
+#define SX932X_PROCESSED_CHANNEL(idx, name, addr)              \
+       {                                                       \
+               .type = IIO_PROXIMITY,                          \
+               .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),     \
+               .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+               .indexed = 1,                                   \
+               .channel = idx,                                 \
+               .address = addr,                                \
+               .event_spec = sx932x_events,                    \
+               .num_event_specs = ARRAY_SIZE(sx932x_events),   \
+               .extend_name = name,                            \
+               .scan_index = idx,                              \
+               .scan_type = {                                  \
+                       .sign = 's',                            \
+                       .realbits = 16,                         \
+                       .storagebits = 16,                      \
+                       .shift = 0,                             \
+               },                                              \
+       }
+
+static const struct iio_chan_spec sx932x_channels[] = {
+       SX932X_RAW_CHANNEL(0, "UC0", SX932X_REG_USE_MSB),
+       SX932X_RAW_CHANNEL(1, "UC1", SX932X_REG_USE_MSB),
+       SX932X_RAW_CHANNEL(2, "UC2", SX932X_REG_USE_MSB),
+       SX932X_RAW_CHANNEL(3, "UC3", SX932X_REG_USE_MSB),
+
+       SX932X_RAW_CHANNEL(4, "AC0", SX932X_REG_AVG_MSB),
+       SX932X_RAW_CHANNEL(5, "AC1", SX932X_REG_AVG_MSB),
+       SX932X_RAW_CHANNEL(6, "AC2", SX932X_REG_AVG_MSB),
+       SX932X_RAW_CHANNEL(7, "AC3", SX932X_REG_AVG_MSB),
+
+       SX932X_RAW_CHANNEL(8,  "DC0", SX932X_REG_DIFF_MSB),
+       SX932X_RAW_CHANNEL(9,  "DC1", SX932X_REG_DIFF_MSB),
+       SX932X_RAW_CHANNEL(10, "DC2", SX932X_REG_DIFF_MSB),
+       SX932X_RAW_CHANNEL(11, "DC3", SX932X_REG_DIFF_MSB),
+
+       SX932X_RAW_CHANNEL(12, "CO0", SX932X_REG_OFFSET_MSB),
+       SX932X_RAW_CHANNEL(13, "CO1", SX932X_REG_OFFSET_MSB),
+       SX932X_RAW_CHANNEL(14, "CO2", SX932X_REG_OFFSET_MSB),
+       SX932X_RAW_CHANNEL(15, "CO3", SX932X_REG_OFFSET_MSB),
+
+       IIO_CHAN_SOFT_TIMESTAMP(16),
+};
+
+static const struct {
+       int val;
+       int val2;
+} sx932x_samp_freq_table[] = {
+       {500, 0}, /* 0000: Min (no idle time) */
+       {66, 666666}, /* 0001: 15 ms */
+       {33, 333333}, /* 0010: 30 ms (Typ.) */
+       {22, 222222}, /* 0011: 45 ms */
+       {16, 666666}, /* 0100: 60 ms */
+       {11, 111111}, /* 0101: 90 ms */
+       {8, 333333}, /* 0110: 120 ms */
+       {5, 0}, /* 0111: 200 ms */
+       {2, 500000}, /* 1000: 400 ms */
+       {1, 666666}, /* 1001: 600 ms */
+       {1, 250000}, /* 1010: 800 ms */
+       {1, 0}, /* 1011: 1 s */
+       {0, 500000}, /* 1100: 2 s */
+       {8, 333333}, /* 1101: 3 s */
+       {0, 250000}, /* 1110: 4 s */
+       {0, 200000}, /* 1111: 5 s */
+};
+static const unsigned int sx932x_scan_period_table[] = {
+       2, 15, 30, 45, 60, 90, 120, 200, 400, 800, 1000, 2000, 3000, 4000, 5000,
+};
+
+static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
+       "500.0 66.666666 33.333333 22.222222 16.666666 "
+       "11.111111 8.333333 5.0 2.500000 1.666666 1.250000 "
+       "1.0 0.500000 8.333333 0.250000 0.200000");
+
+
+static const struct regmap_range sx932x_writable_reg_ranges[] = {
+       regmap_reg_range(SX932X_REG_IRQ_MSK, SX932X_REG_IRQ_CFG2),
+       regmap_reg_range(SX932X_REG_GNRL_CTRL0, SX932X_REG_GNRL_CTRL1),
+       /* Leave i2c and clock spreading as unavailable */
+       regmap_reg_range(SX932X_REG_AFE_CTRL0, SX932X_REG_AFE_CTRL9),
+       regmap_reg_range(SX932X_REG_PROX_CTRL0, SX932X_REG_PROX_CTRL7),
+       regmap_reg_range(SX932X_REG_ADV_CTRL0, SX932X_REG_ADV_CTRL20),
+       regmap_reg_range(SX932X_REG_PHASE_SEL, SX932X_REG_PHASE_SEL),
+       regmap_reg_range(SX932X_REG_OFFSET_MSB, SX932X_REG_OFFSET_LSB),
+       regmap_reg_range(SX932X_REG_RESET, SX932X_REG_RESET),
+};
+
+static const struct regmap_access_table sx932x_writeable_regs = {
+       .yes_ranges = sx932x_writable_reg_ranges,
+       .n_yes_ranges = ARRAY_SIZE(sx932x_writable_reg_ranges),
+};
+
+/*
+ * All allocated registers are readable, so we just list unallocated
+ * ones.
+ */
+static const struct regmap_range sx932x_non_readable_reg_ranges[] = {
+       regmap_reg_range(SX932X_REG_IRQ_CFG2 + 1, SX932X_REG_GNRL_CTRL0 - 1),
+       regmap_reg_range(SX932X_REG_GNRL_CTRL1 + 1, SX932X_REG_AFE_CTRL0 - 1),
+       regmap_reg_range(SX932X_REG_AFE_CTRL9 + 1, SX932X_REG_PROX_CTRL0 - 1),
+       regmap_reg_range(SX932X_REG_PROX_CTRL7 + 1, SX932X_REG_ADV_CTRL0 - 1),
+       regmap_reg_range(SX932X_REG_ADV_CTRL20 + 1, SX932X_REG_PHASE_SEL - 1),
+       regmap_reg_range(SX932X_REG_SAR_LSB + 1, SX932X_REG_RESET - 1),
+       regmap_reg_range(SX932X_REG_RESET + 1, SX932X_REG_WHOAMI - 1),
+       regmap_reg_range(SX932X_REG_WHOAMI + 1, SX932X_REG_REVISION - 1),
+};
+
+static const struct regmap_access_table sx932x_readable_regs = {
+       .no_ranges = sx932x_non_readable_reg_ranges,
+       .n_no_ranges = ARRAY_SIZE(sx932x_non_readable_reg_ranges),
+};
+
+static const struct regmap_range sx932x_volatile_reg_ranges[] = {
+       regmap_reg_range(SX932X_REG_IRQ_SRC, SX932X_REG_STAT3),
+       regmap_reg_range(SX932X_REG_USE_MSB, SX932X_REG_DIFF_LSB),
+       regmap_reg_range(SX932X_REG_SAR_MSB, SX932X_REG_SAR_LSB),
+       regmap_reg_range(SX932X_REG_WHOAMI, SX932X_REG_WHOAMI),
+       regmap_reg_range(SX932X_REG_REVISION, SX932X_REG_REVISION),
+};
+
+static const struct regmap_access_table sx932x_volatile_regs = {
+       .yes_ranges = sx932x_volatile_reg_ranges,
+       .n_yes_ranges = ARRAY_SIZE(sx932x_volatile_reg_ranges),
+};
+
+static const struct regmap_config sx932x_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 8,
+
+       .max_register = SX932X_REG_REVISION,
+       .cache_type = REGCACHE_RBTREE,
+
+       .wr_table = &sx932x_writeable_regs,
+       .rd_table = &sx932x_readable_regs,
+       .volatile_table = &sx932x_volatile_regs,
+};
+
+static int sx932x_inc_users(struct sx932x_data *data, int *counter,
+                           unsigned int reg, unsigned int bitmask)
+{
+       ++(*counter);
+       if (*counter != 1)
+               /* Bit is already active, nothing to do. */
+               return 0;
+
+       return regmap_update_bits(data->regmap, reg, bitmask, bitmask);
+}
+
+static int sx932x_dec_users(struct sx932x_data *data, int *counter,
+                           unsigned int reg, unsigned int bitmask)
+{
+       --(*counter);
+       if (*counter != 0)
+               /* There are more users, do not deactivate. */
+               return 0;
+
+       return regmap_update_bits(data->regmap, reg, bitmask, 0);
+}
+
+static int sx932x_inc_chan_users(struct sx932x_data *data, int chan)
+{
+       return sx932x_inc_users(data, &data->channel_users[chan],
+                               SX932X_REG_PROX_CTRL0, BIT(chan));
+}
+
+static int sx932x_dec_chan_users(struct sx932x_data *data, int chan)
+{
+       return sx932x_dec_users(data, &data->channel_users[chan],
+                               SX932X_REG_PROX_CTRL0, BIT(chan));
+}
+
+static int sx932x_inc_data_rdy_users(struct sx932x_data *data)
+{
+       return sx932x_inc_users(data, &data->data_rdy_users,
+                               SX932X_REG_IRQ_MSK, SX932X_CONVDONE_IRQ);
+}
+
+static int sx932x_dec_data_rdy_users(struct sx932x_data *data)
+{
+       return sx932x_dec_users(data, &data->data_rdy_users,
+                               SX932X_REG_IRQ_MSK, SX932X_CONVDONE_IRQ);
+}
+
+static int sx932x_inc_close_far_users(struct sx932x_data *data)
+{
+       return sx932x_inc_users(data, &data->close_far_users,
+                               SX932X_REG_IRQ_MSK,
+                               SX932X_CLOSE_IRQ | SX932X_FAR_IRQ);
+}
+
+static int sx932x_dec_close_far_users(struct sx932x_data *data)
+{
+       return sx932x_dec_users(data, &data->close_far_users,
+                               SX932X_REG_IRQ_MSK,
+                               SX932X_CLOSE_IRQ | SX932X_FAR_IRQ);
+}
+
+static int sx932x_read_prox_data(struct sx932x_data *data,
+                                const struct iio_chan_spec *chan,
+                                int *val)
+{
+       int ret;
+       __be16 regval;
+       const int regid = chan->channel & 3;
+
+       ret = regmap_write(data->regmap, SX932X_REG_PHASE_SEL, regid);
+       if (ret < 0)
+               return ret;
+
+       ret = regmap_bulk_read(data->regmap, chan->address, &regval, 2);
+       if (ret < 0)
+               return ret;
+
+       *val = sign_extend32(be16_to_cpu(regval), 15);
+
+       return 0;
+}
+
+static int sx932x_read_stat_data(struct sx932x_data *data,
+               const struct iio_chan_spec
+               *chan,
+               int *val)
+{
+       int ret;
+
+       ret = regmap_read(data->regmap, chan->address, val);
+       if (ret < 0)
+               return ret;
+
+       return 0;
+}
+
+/*
+ * If we have no interrupt support, we have to wait for a scan period
+ * after enabling a channel to get a result.
+ */
+static int sx932x_wait_for_sample(struct sx932x_data *data)
+{
+       int ret;
+       unsigned int val;
+
+       ret = regmap_read(data->regmap, SX932X_REG_PROX_CTRL0, &val);
+       if (ret < 0)
+               return ret;
+
+       val = (val & SX932X_SCAN_PERIOD_MASK) >> SX932X_SCAN_PERIOD_SHIFT;
+
+       msleep(sx932x_scan_period_table[val]);
+
+       return 0;
+}
+
+static int sx932x_read_stat(struct sx932x_data *data,
+                                const struct iio_chan_spec *chan,
+                                int *val)
+{
+       int ret;
+
+       mutex_lock(&data->mutex);
+
+       ret = sx932x_inc_chan_users(data, chan->channel);
+       if (ret < 0)
+               goto out;
+
+       ret = sx932x_inc_data_rdy_users(data);
+       if (ret < 0)
+               goto out_dec_chan;
+
+       mutex_unlock(&data->mutex);
+
+       if (data->client->irq > 0)
+               ret = wait_for_completion_interruptible(&data->completion);
+       else
+               ret = sx932x_wait_for_sample(data);
+
+       mutex_lock(&data->mutex);
+
+       if (ret < 0)
+               goto out_dec_data_rdy;
+
+       ret = sx932x_read_stat_data(data, chan, val);
+       if (ret < 0)
+               goto out_dec_data_rdy;
+
+       ret = sx932x_dec_data_rdy_users(data);
+       if (ret < 0)
+               goto out_dec_chan;
+
+       ret = sx932x_dec_chan_users(data, chan->channel);
+       if (ret < 0)
+               goto out;
+
+       ret = IIO_VAL_INT;
+
+       goto out;
+
+out_dec_data_rdy:
+       sx932x_dec_data_rdy_users(data);
+out_dec_chan:
+       sx932x_dec_chan_users(data, chan->channel);
+out:
+       mutex_unlock(&data->mutex);
+       reinit_completion(&data->completion);
+
+       return ret;
+}
+
+static int sx932x_read_proximity(struct sx932x_data *data,
+                                const struct iio_chan_spec *chan,
+                                int *val)
+{
+       int ret;
+
+       mutex_lock(&data->mutex);
+
+       ret = sx932x_inc_chan_users(data, chan->channel);
+       if (ret < 0)
+               goto out;
+
+       ret = sx932x_inc_data_rdy_users(data);
+       if (ret < 0)
+               goto out_dec_chan;
+
+       mutex_unlock(&data->mutex);
+
+       if (data->client->irq > 0)
+               ret = wait_for_completion_interruptible(&data->completion);
+       else
+               ret = sx932x_wait_for_sample(data);
+
+       mutex_lock(&data->mutex);
+
+       if (ret < 0)
+               goto out_dec_data_rdy;
+
+       ret = sx932x_read_prox_data(data, chan, val);
+       if (ret < 0)
+               goto out_dec_data_rdy;
+
+       ret = sx932x_dec_data_rdy_users(data);
+       if (ret < 0)
+               goto out_dec_chan;
+
+       ret = sx932x_dec_chan_users(data, chan->channel);
+       if (ret < 0)
+               goto out;
+
+       ret = IIO_VAL_INT;
+
+       goto out;
+
+out_dec_data_rdy:
+       sx932x_dec_data_rdy_users(data);
+out_dec_chan:
+       sx932x_dec_chan_users(data, chan->channel);
+out:
+       mutex_unlock(&data->mutex);
+       reinit_completion(&data->completion);
+
+       return ret;
+}
+
+static int sx932x_read_samp_freq(struct sx932x_data *data,
+                                int *val, int *val2)
+{
+       int ret;
+       unsigned int regval;
+
+       mutex_lock(&data->mutex);
+       ret = regmap_read(data->regmap, SX932X_REG_PROX_CTRL0, &regval);
+       mutex_unlock(&data->mutex);
+
+       if (ret < 0)
+               return ret;
+
+       regval = (regval & SX932X_SCAN_PERIOD_MASK) >> SX932X_SCAN_PERIOD_SHIFT;
+       *val = sx932x_samp_freq_table[regval].val;
+       *val2 = sx932x_samp_freq_table[regval].val2;
+
+       return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int sx932x_read_raw(struct iio_dev *indio_dev,
+                          const struct iio_chan_spec *chan,
+                          int *val, int *val2, long mask)
+{
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int ret;
+
+       switch (chan->type) {
+       case IIO_PROXIMITY:
+               switch (mask) {
+               case IIO_CHAN_INFO_RAW:
+                       mutex_lock(&indio_dev->mlock);
+
+                       if (iio_buffer_enabled(indio_dev)) {
+                               mutex_unlock(&indio_dev->mlock);
+                               return -EBUSY;
+                       }
+                       ret = sx932x_read_proximity(data, chan, val);
+                       mutex_unlock(&indio_dev->mlock);
+                       return ret;
+               case IIO_CHAN_INFO_PROCESSED:
+                       mutex_lock(&indio_dev->mlock);
+
+                       if (iio_buffer_enabled(indio_dev)) {
+                               mutex_unlock(&indio_dev->mlock);
+                               return -EBUSY;
+                       }
+                       ret = sx932x_read_stat(data, chan, val);
+                       mutex_unlock(&indio_dev->mlock);
+                       return ret;
+               case IIO_CHAN_INFO_SAMP_FREQ:
+                       return sx932x_read_samp_freq(data, val, val2);
+               default:
+                       return -EINVAL;
+               }
+       default:
+               return -EINVAL;
+       }
+}
+
+static int sx932x_set_samp_freq(struct sx932x_data *data,
+                               int val, int val2)
+{
+       int i, ret;
+
+       for (i = 0; i < ARRAY_SIZE(sx932x_samp_freq_table); i++)
+               if (val == sx932x_samp_freq_table[i].val &&
+                   val2 == sx932x_samp_freq_table[i].val2)
+                       break;
+
+       if (i == ARRAY_SIZE(sx932x_samp_freq_table))
+               return -EINVAL;
+
+       mutex_lock(&data->mutex);
+
+       ret = regmap_update_bits(data->regmap, SX932X_REG_PROX_CTRL0,
+                                SX932X_SCAN_PERIOD_MASK,
+                                i << SX932X_SCAN_PERIOD_SHIFT);
+
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int sx932x_write_raw(struct iio_dev *indio_dev,
+                           const struct iio_chan_spec *chan,
+                           int val, int val2, long mask)
+{
+       struct sx932x_data *data = iio_priv(indio_dev);
+
+       switch (chan->type) {
+       case IIO_PROXIMITY:
+               switch (mask) {
+               case IIO_CHAN_INFO_SAMP_FREQ:
+                       return sx932x_set_samp_freq(data, val, val2);
+               default:
+                       return -EINVAL;
+               }
+       default:
+               return -EINVAL;
+       }
+}
+
+static irqreturn_t sx932x_irq_handler(int irq, void *private)
+{
+       struct iio_dev *indio_dev = private;
+       struct sx932x_data *data = iio_priv(indio_dev);
+
+       if (data->trigger_enabled)
+               iio_trigger_poll(data->trig);
+
+       /*
+        * Even if no event is enabled, we need to wake the thread to
+        * clear the interrupt state by reading SX932X_REG_IRQ_SRC.  It
+        * is not possible to do that here because regmap_read takes a
+        * mutex.
+        */
+       return IRQ_WAKE_THREAD;
+}
+
+static void sx932x_push_events(struct iio_dev *indio_dev)
+{
+       int ret;
+       unsigned int val, chan;
+       struct sx932x_data *data = iio_priv(indio_dev);
+
+       ret = regmap_read(data->regmap, SX932X_REG_STAT0, &val);
+       if (ret < 0) {
+               dev_err(&data->client->dev, "i2c transfer error in irq\n");
+               return;
+       }
+
+       for (chan = 0; chan < SX932X_NUM_CHANNELS; chan++) {
+               int dir;
+               u64 ev;
+               bool new_prox = val & BIT(chan);
+
+               if (!data->event_enabled[chan])
+                       continue;
+               if (new_prox == data->prox_stat[chan])
+                       /* No change on this channel. */
+                       continue;
+
+               dir = new_prox ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
+               ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
+                                         IIO_EV_TYPE_THRESH, dir);
+               iio_push_event(indio_dev, ev, iio_get_time_ns(indio_dev));
+               data->prox_stat[chan] = new_prox;
+       }
+}
+
+static irqreturn_t sx932x_irq_thread_handler(int irq, void *private)
+{
+       struct iio_dev *indio_dev = private;
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int ret;
+       unsigned int val;
+
+       mutex_lock(&data->mutex);
+
+       ret = regmap_read(data->regmap, SX932X_REG_IRQ_SRC, &val);
+       if (ret < 0) {
+               dev_err(&data->client->dev, "i2c transfer error in irq\n");
+               goto out;
+       }
+
+       if (val & (SX932X_CLOSE_IRQ | SX932X_FAR_IRQ))
+               sx932x_push_events(indio_dev);
+
+       if (val & SX932X_CONVDONE_IRQ)
+               complete(&data->completion);
+
+out:
+       mutex_unlock(&data->mutex);
+
+       return IRQ_HANDLED;
+}
+
+static int sx932x_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 sx932x_data *data = iio_priv(indio_dev);
+
+       if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
+           dir != IIO_EV_DIR_EITHER)
+               return -EINVAL;
+
+       return data->event_enabled[chan->channel & SX932X_CHAN_MASK];
+}
+
+static int sx932x_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 sx932x_data *data = iio_priv(indio_dev);
+       int ret;
+
+       if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
+           dir != IIO_EV_DIR_EITHER)
+               return -EINVAL;
+
+       mutex_lock(&data->mutex);
+
+       if (state == 1) {
+               ret = sx932x_inc_chan_users(data, chan->channel);
+               if (ret < 0)
+                       goto out_unlock;
+               ret = sx932x_inc_close_far_users(data);
+               if (ret < 0)
+                       goto out_undo_chan;
+       } else {
+               ret = sx932x_dec_chan_users(data, chan->channel);
+               if (ret < 0)
+                       goto out_unlock;
+               ret = sx932x_dec_close_far_users(data);
+               if (ret < 0)
+                       goto out_undo_chan;
+       }
+
+       data->event_enabled[chan->channel & SX932X_CHAN_MASK] = state;
+       goto out_unlock;
+
+out_undo_chan:
+       if (state == 1)
+               sx932x_dec_chan_users(data, chan->channel);
+       else
+               sx932x_inc_chan_users(data, chan->channel);
+out_unlock:
+       mutex_unlock(&data->mutex);
+       return ret;
+}
+
+static int sx932x_update_scan_mode(struct iio_dev *indio_dev,
+                                  const unsigned long *scan_mask)
+{
+       struct sx932x_data *data = iio_priv(indio_dev);
+
+       mutex_lock(&data->mutex);
+       kfree(data->buffer);
+       data->buffer = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);
+       mutex_unlock(&data->mutex);
+
+       if (data->buffer == NULL)
+               return -ENOMEM;
+
+       return 0;
+}
+
+static ssize_t sx932x_uid_show(struct device *dev,
+                              struct device_attribute *attr,
+                              char *buf)
+{
+       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+#ifdef CONFIG_ACPI
+       struct acpi_device *adev = ACPI_COMPANION(dev);
+
+       if (adev != NULL)
+               return scnprintf(buf, PAGE_SIZE, "%s\n", acpi_device_uid(adev));
+#endif
+       return scnprintf(buf, PAGE_SIZE, "%d\n", indio_dev->id);
+}
+
+static IIO_DEVICE_ATTR(uid, 0444, sx932x_uid_show, NULL, 0);
+
+struct sx932x_ctrl_attribute {
+       struct device_attribute dev_attr;
+       u8 ctrl;
+};
+
+static inline struct sx932x_ctrl_attribute *sx932x_to_ctrl_attr(
+               struct device_attribute *attr)
+{
+       return container_of(attr, struct sx932x_ctrl_attribute, dev_attr);
+}
+
+static ssize_t sx932x_show_ctrl_attr(struct device *dev,
+                                    struct device_attribute *dev_attr,
+                                    char *buf)
+{
+       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+       struct sx932x_ctrl_attribute *attr = sx932x_to_ctrl_attr(dev_attr);
+       struct sx932x_data *data = iio_priv(indio_dev);
+       unsigned int val;
+       int ret;
+
+       mutex_lock(&data->mutex);
+       ret = regmap_read(data->regmap, attr->ctrl, &val);
+       mutex_unlock(&data->mutex);
+       if (ret)
+               return ret;
+
+       return scnprintf(buf, PAGE_SIZE, "%02x\n", val);
+}
+
+static ssize_t sx932x_store_ctrl_attr(struct device *dev,
+                                     struct device_attribute *dev_attr,
+                                     const char *buf, size_t len)
+{
+       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+       struct sx932x_ctrl_attribute *attr = sx932x_to_ctrl_attr(dev_attr);
+       struct sx932x_data *data = iio_priv(indio_dev);
+       u8 val;
+       int ret;
+
+       if (kstrtou8(buf, 0, &val))
+               return -EINVAL;
+
+       mutex_lock(&data->mutex);
+       ret = regmap_write(data->regmap, attr->ctrl, val);
+       mutex_unlock(&data->mutex);
+       if (ret)
+               return ret;
+
+       return len;
+}
+
+#define SX932X_CTRL_ATTR_FILL(_name, _mode, _show, _store, _ctrl, _offset) \
+       { .dev_attr     = __ATTR(_name, _mode, _show, _store),          \
+         .ctrl         = _ctrl + _offset }
+
+#define SX932X_CTRL_ATTR(_name, _mode, _show, _store, _ctrl, _offset)  \
+       struct sx932x_ctrl_attribute sx932x_ctrl_attr_##_name =         \
+               SX932X_CTRL_ATTR_FILL( \
+                       _name, _mode, _show, _store, _ctrl, _offset)
+
+#define SX932X_ADV_CTRL_RW(_ctrl)                                      \
+       SX932X_CTRL_ATTR(adv_ctrl##_ctrl##_raw, 0644,                   \
+                        sx932x_show_ctrl_attr, sx932x_store_ctrl_attr, \
+                        _ctrl, SX932X_REG_ADV_CTRL0)
+
+static SX932X_ADV_CTRL_RW(0);
+static SX932X_ADV_CTRL_RW(1);
+static SX932X_ADV_CTRL_RW(2);
+static SX932X_ADV_CTRL_RW(3);
+static SX932X_ADV_CTRL_RW(4);
+static SX932X_ADV_CTRL_RW(5);
+static SX932X_ADV_CTRL_RW(6);
+static SX932X_ADV_CTRL_RW(7);
+static SX932X_ADV_CTRL_RW(8);
+static SX932X_ADV_CTRL_RW(9);
+static SX932X_ADV_CTRL_RW(10);
+static SX932X_ADV_CTRL_RW(11);
+static SX932X_ADV_CTRL_RW(12);
+static SX932X_ADV_CTRL_RW(13);
+static SX932X_ADV_CTRL_RW(14);
+static SX932X_ADV_CTRL_RW(15);
+static SX932X_ADV_CTRL_RW(16);
+static SX932X_ADV_CTRL_RW(17);
+static SX932X_ADV_CTRL_RW(18);
+static SX932X_ADV_CTRL_RW(19);
+static SX932X_ADV_CTRL_RW(20);
+
+static struct attribute *sx932x_attributes[] = {
+       &iio_const_attr_sampling_frequency_available.dev_attr.attr,
+       &iio_dev_attr_uid.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl0_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl1_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl2_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl3_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl4_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl5_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl6_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl7_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl8_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl9_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl10_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl11_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl12_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl13_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl14_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl15_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl16_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl17_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl18_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl19_raw.dev_attr.attr,
+       &sx932x_ctrl_attr_adv_ctrl20_raw.dev_attr.attr,
+       NULL,
+};
+
+static const struct attribute_group sx932x_attribute_group = {
+       .attrs = sx932x_attributes,
+};
+
+static const struct iio_info sx932x_info = {
+       .attrs = &sx932x_attribute_group,
+       .read_raw = &sx932x_read_raw,
+       .write_raw = &sx932x_write_raw,
+       .read_event_config = &sx932x_read_event_config,
+       .write_event_config = &sx932x_write_event_config,
+       .update_scan_mode = &sx932x_update_scan_mode,
+};
+
+static int sx932x_set_trigger_state(struct iio_trigger *trig,
+                                   bool state)
+{
+       struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&data->mutex);
+
+       if (state)
+               ret = sx932x_inc_data_rdy_users(data);
+       else
+               ret = sx932x_dec_data_rdy_users(data);
+       if (ret < 0)
+               goto out;
+
+       data->trigger_enabled = state;
+
+out:
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static const struct iio_trigger_ops sx932x_trigger_ops = {
+       .set_trigger_state = sx932x_set_trigger_state,
+};
+
+static irqreturn_t sx932x_trigger_handler(int irq, void *private)
+{
+       struct iio_poll_func *pf = private;
+       struct iio_dev *indio_dev = pf->indio_dev;
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int val, bit, ret, i = 0;
+
+       mutex_lock(&data->mutex);
+
+       for_each_set_bit(bit, indio_dev->active_scan_mask,
+                        indio_dev->masklength) {
+               ret = sx932x_read_prox_data(data, &indio_dev->channels[bit],
+                                           &val);
+               if (ret < 0)
+                       goto out;
+
+               data->buffer[i++] = val;
+       }
+
+       iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+                                          iio_get_time_ns(indio_dev));
+out:
+       mutex_unlock(&data->mutex);
+
+       iio_trigger_notify_done(indio_dev->trig);
+
+       return IRQ_HANDLED;
+}
+
+static int sx932x_buffer_preenable(struct iio_dev *indio_dev)
+{
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int ret = 0, i;
+
+       mutex_lock(&data->mutex);
+
+       for (i = 0; i < SX932X_NUM_CHANNELS; i++)
+               if (test_bit(i, indio_dev->active_scan_mask)) {
+                       ret = sx932x_inc_chan_users(data, i);
+                       if (ret)
+                               break;
+               }
+
+       if (ret)
+               for (i = i - 1; i >= 0; i--)
+                       if (test_bit(i, indio_dev->active_scan_mask))
+                               sx932x_dec_chan_users(data, i);
+
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int sx932x_buffer_predisable(struct iio_dev *indio_dev)
+{
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int ret = 0, i;
+
+       iio_triggered_buffer_predisable(indio_dev);
+
+       mutex_lock(&data->mutex);
+
+       for (i = 0; i < SX932X_NUM_CHANNELS; i++)
+               if (test_bit(i, indio_dev->active_scan_mask)) {
+                       ret = sx932x_dec_chan_users(data, i);
+                       if (ret)
+                               break;
+               }
+
+       if (ret)
+               for (i = i - 1; i >= 0; i--)
+                       if (test_bit(i, indio_dev->active_scan_mask))
+                               sx932x_inc_chan_users(data, i);
+
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static const struct iio_buffer_setup_ops sx932x_buffer_setup_ops = {
+       .preenable = sx932x_buffer_preenable,
+       .postenable = iio_triggered_buffer_postenable,
+       .predisable = sx932x_buffer_predisable,
+};
+#define SX932X_REG_CONFIG(_property_prefix, _property_name, _reg_addr,         
\
+                         _def_value)                                          \
+       {                                                                      \
+               .property = _property_prefix ",reg_" _property_name,           \
+               .reg_addr = SX932X_REG_##_reg_addr, .def_value = _def_value,   \
+       }
+
+#define SX932X_DEFAULT_REG_CONFIGS(_property_prefix)                           
\
+       {                                                                      \
+               {                                                              \
+                       .property = NULL,                                      \
+                       .reg_addr = SX932X_REG_ADV_CTRL11,                     \
+                       .def_value = (5 << 4) | 2,                             \
+               },                                                             \
+                       {                                                      \
+                               .property = NULL,                              \
+                               .reg_addr = SX932X_REG_ADV_CTRL12,             \
+                               .def_value = (11 << 4) | 5,                    \
+                       },                                                     \
+                       SX932X_REG_CONFIG(_property_prefix, "adv_ctrl10",      \
+                                         ADV_CTRL10, (5 << 4) | 12),          \
+                       SX932X_REG_CONFIG(_property_prefix, "afe_ctrl4",       \
+                                         AFE_CTRL4, 7),                       \
+                       SX932X_REG_CONFIG(_property_prefix, "afe_ctrl7",       \
+                                         AFE_CTRL7, 7),                       \
+                       SX932X_REG_CONFIG(_property_prefix, "afe_ctrl9",       \
+                                         AFE_CTRL9, 15),                      \
+                       SX932X_REG_CONFIG(_property_prefix, "prox_ctrl0",      \
+                                         PROX_CTRL0, (2 << 3) | 2),           \
+                       SX932X_REG_CONFIG(_property_prefix, "prox_ctrl1",      \
+                                         PROX_CTRL1, (2 << 3) | 2),           \
+                       SX932X_REG_CONFIG(_property_prefix, "prox_ctrl2",      \
+                                         PROX_CTRL2, 0x80 | 16),              \
+                       SX932X_REG_CONFIG(_property_prefix, "prox_ctrl4",      \
+                                         PROX_CTRL4, (1 << 3) | 4),           \
+                       SX932X_REG_CONFIG(_property_prefix, "prox_ctrl5",      \
+                                         PROX_CTRL5, (1 << 4) | 2),           \
+                       SX932X_REG_CONFIG(_property_prefix, "prox_ctrl6",      \
+                                         PROX_CTRL6, 60),                     \
+                       SX932X_REG_CONFIG(_property_prefix, "prox_ctrl7",      \
+                                         PROX_CTRL7, 88),                     \
+                       SX932X_REG_CONFIG(_property_prefix, "adv_ctrl16",      \
+                                         ADV_CTRL16, (3 << 4) | (2 << 2)),    \
+                       SX932X_REG_CONFIG(_property_prefix, "adv_ctrl17",      \
+                                         ADV_CTRL17, (5 << 4) | 6),           \
+                       SX932X_REG_CONFIG(_property_prefix, "adv_ctrl18",      \
+                                         ADV_CTRL18, (3 << 4) | 3),           \
+                       SX932X_REG_CONFIG(_property_prefix, "gnrl_ctrl1",      \
+                                         GNRL_CTRL1, 0x2f),                   \
+                       {                                                      \
+                               .property = NULL,                              \
+                               .reg_addr = 0,                                 \
+                               .def_value = 0,                                \
+                       },                                                     \
+       }
+
+#ifdef CONFIG_ACPI
+static const struct sx932x_reg_config sx9320_reg_config[] =
+       SX932X_DEFAULT_REG_CONFIGS(SX9320_ACPI_NAME);
+static const struct sx932x_reg_config sx9321_reg_config[] =
+       SX932X_DEFAULT_REG_CONFIGS(SX9321_ACPI_NAME);
+static const struct sx932x_reg_config sx9324_reg_config[] =
+       SX932X_DEFAULT_REG_CONFIGS(SX9324_ACPI_NAME);
+#else
+static const struct sx932x_reg_config sx9320_reg_config[] =
+       SX932X_DEFAULT_REG_CONFIGS("semtech,");
+static const struct sx932x_reg_config sx9321_reg_config[] =
+       SX932X_DEFAULT_REG_CONFIGS("semtech,");
+static const struct sx932x_reg_config sx9324_reg_config[] =
+       SX932X_DEFAULT_REG_CONFIGS("semtech,");
+#endif
+static const struct sx932x_reg_config *sx932x_reg_configs[] = {
+       sx9320_reg_config, sx9321_reg_config, sx9324_reg_config
+};
+static int sx932x_read_register_property(struct device *dev,
+                                        const struct sx932x_reg_config *cfg,
+                                        u8 *value)
+{
+#ifdef CONFIG_ACPI
+       const union acpi_object *acpi_value = NULL;
+#endif
+       int ret;
+
+       if ((dev == NULL) || (cfg->property == NULL)) {
+               *value = cfg->def_value;
+               return 0;
+       }
+
+#ifdef CONFIG_ACPI
+       ret = acpi_dev_get_property(ACPI_COMPANION(dev), cfg->property,
+                                   ACPI_TYPE_INTEGER, &acpi_value);
+#else
+       ret = of_property_read_u8(dev->of_node, cfg->property, value);
+#endif
+       if (ret)
+               *value = cfg->def_value;
+#ifdef CONFIG_ACPI
+       *value = acpi_value ? (u8)acpi_value->integer.value : cfg->def_value;
+#endif
+       return 0;
+}
+
+static int sx932x_load_config(struct device *dev, struct sx932x_data *data)
+{
+       u8 val;
+       int i, ret;
+       const struct sx932x_reg_config *cfg;
+
+       for (i = 0; data->reg_config[i].reg_addr != 0; i++) {
+               cfg = &data->reg_config[i];
+               ret = sx932x_read_register_property(dev, cfg, &val);
+               if (ret < 0)
+                       return ret;
+               ret = regmap_write(data->regmap, cfg->reg_addr, val);
+               if (ret < 0)
+                       return ret;
+       }
+       return 0;
+}
+
+/* Activate all channels and perform an initial compensation. */
+static int sx932x_init_compensation(struct iio_dev *indio_dev)
+{
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int i, ret;
+       bool success = false;
+       unsigned int val;
+
+       for (i = 100; i >= 0; i--) {
+               usleep_range(10000, 20000);
+               ret = regmap_read(data->regmap, SX932X_REG_STAT2, &val);
+               if (ret < 0)
+                       goto out;
+               if (!(val & SX932X_COMPSTAT_MASK)) {
+                       success = true;
+                       break;
+               }
+       }
+
+       if (success) {
+               dev_info(&data->client->dev,
+                        "initial compensation success");
+       } else {
+               dev_err(&data->client->dev,
+                       "initial compensation timed out: 0x%02x", val);
+               ret = -ETIMEDOUT;
+       }
+
+out:
+       return ret;
+}
+
+static int sx932x_init_device(struct iio_dev *indio_dev)
+{
+       struct device *dev = &indio_dev->dev;
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int ret;
+       unsigned int val;
+
+       ret = regmap_read(data->regmap, SX932X_REG_WHOAMI, &val);
+       if (ret < 0 || (val != SX9320_WHOAMI && val != SX9321_WHOAMI &&
+                       val != SX9324_WHOAMI)) {
+               dev_err(&data->client->dev,
+                       "Unable to identify the chip: %d - 0x%02x", ret, val);
+               return -ENODEV;
+       }
+
+       ret = regmap_write(data->regmap, SX932X_REG_IRQ_MSK, 0);
+       if (ret < 0)
+               return ret;
+
+       ret = regmap_write(data->regmap, SX932X_REG_RESET,
+                          SX932X_SOFT_RESET);
+       if (ret < 0)
+               return ret;
+
+       // wait for the reset to be completed
+       usleep_range(10000, 20000);
+
+       ret = regmap_write(data->regmap, SX932X_REG_RESET, 0);
+       if (ret < 0)
+               return ret;
+
+       ret = regmap_read(data->regmap, SX932X_REG_IRQ_SRC, &val);
+       if (ret < 0)
+               return ret;
+
+       ret = sx932x_load_config(dev, data);
+       if (ret < 0)
+               return ret;
+
+       return sx932x_init_compensation(indio_dev);
+}
+
+static int sx932x_probe(struct i2c_client *client,
+                       const struct i2c_device_id *i2c_id)
+{
+       int ret;
+       struct iio_dev *indio_dev;
+       const struct acpi_device_id *acpi_id;
+       struct sx932x_data *data;
+
+       indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+       if (indio_dev == NULL)
+               return -ENOMEM;
+
+       data = iio_priv(indio_dev);
+       data->client = client;
+       if (i2c_id) {
+               data->reg_config = sx932x_reg_configs[i2c_id->driver_data];
+       } else if (ACPI_HANDLE(&client->dev)) {
+               acpi_id = acpi_match_device(
+                               client->dev.driver->acpi_match_table,
+                               &client->dev);
+               if (!acpi_id) {
+                       dev_err(&client->dev, "No driver data\n");
+                       return -EINVAL;
+               }
+               data->reg_config = sx932x_reg_configs[acpi_id->driver_data];
+       } else {
+               return -ENODEV;
+       }
+       mutex_init(&data->mutex);
+       init_completion(&data->completion);
+       data->trigger_enabled = false;
+
+       data->regmap = devm_regmap_init_i2c(client, &sx932x_regmap_config);
+       if (IS_ERR(data->regmap))
+               return PTR_ERR(data->regmap);
+       ACPI_COMPANION_SET(&indio_dev->dev, ACPI_COMPANION(&client->dev));
+       indio_dev->dev.parent = &client->dev;
+       indio_dev->name = SX932X_DRIVER_NAME;
+       indio_dev->channels = sx932x_channels;
+       indio_dev->num_channels = ARRAY_SIZE(sx932x_channels);
+       indio_dev->info = &sx932x_info;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       i2c_set_clientdata(client, indio_dev);
+
+       ret = sx932x_init_device(indio_dev);
+       if (ret < 0) {
+               dev_err(&client->dev, "tried to init sx932x - error %d\n",
+                       ret);
+               return ret;
+       }
+
+       if (client->irq <= 0)
+               dev_warn(&client->dev, "no valid irq found\n");
+       else {
+               ret = devm_request_threaded_irq(&client->dev, client->irq,
+                               sx932x_irq_handler, sx932x_irq_thread_handler,
+                               IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+                               SX932X_IRQ_NAME, indio_dev);
+               if (ret < 0)
+                       return ret;
+
+               data->trig = devm_iio_trigger_alloc(&client->dev,
+                               "%s-dev%d", indio_dev->name, indio_dev->id);
+               if (!data->trig)
+                       return -ENOMEM;
+
+               data->trig->dev.parent = &client->dev;
+               data->trig->ops = &sx932x_trigger_ops;
+               iio_trigger_set_drvdata(data->trig, indio_dev);
+
+               ret = iio_trigger_register(data->trig);
+               if (ret)
+                       return ret;
+       }
+
+       ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev,
+                                             NULL, sx932x_trigger_handler,
+                                             &sx932x_buffer_setup_ops);
+       if (ret < 0)
+               goto out_trigger_unregister;
+
+       ret = devm_iio_device_register(&client->dev, indio_dev);
+       if (ret < 0)
+               goto out_trigger_unregister;
+
+       return 0;
+
+out_trigger_unregister:
+       if (client->irq > 0)
+               iio_trigger_unregister(data->trig);
+
+       return ret;
+}
+
+static int sx932x_remove(struct i2c_client *client)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(client);
+       struct sx932x_data *data = iio_priv(indio_dev);
+
+       if (client->irq > 0)
+               iio_trigger_unregister(data->trig);
+       kfree(data->buffer);
+       return 0;
+}
+
+static int __maybe_unused sx932x_suspend(struct device *dev)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&data->mutex);
+       ret = regmap_read(data->regmap, SX932X_REG_GNRL_CTRL1,
+                         &data->suspend_reg_gnrl_ctrl1);
+
+       if (ret < 0)
+               goto out;
+
+       // disable all phases, send the device to sleep
+       ret = regmap_write(data->regmap, SX932X_REG_GNRL_CTRL1, 0);
+
+out:
+       mutex_unlock(&data->mutex);
+       return ret;
+}
+
+static int __maybe_unused sx932x_resume(struct device *dev)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+       struct sx932x_data *data = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&data->mutex);
+       ret = regmap_write(data->regmap, SX932X_REG_GNRL_CTRL1,
+                          data->suspend_reg_gnrl_ctrl1);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static const struct dev_pm_ops sx932x_pm_ops = {
+       SET_SYSTEM_SLEEP_PM_OPS(sx932x_suspend, sx932x_resume)
+};
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id sx932x_acpi_match[] = {
+       { SX9320_ACPI_NAME, 0 },
+       { SX9321_ACPI_NAME, 1 },
+       { SX9324_ACPI_NAME, 2 },
+       {},
+};
+MODULE_DEVICE_TABLE(acpi, sx932x_acpi_match);
+#endif
+#ifdef CONFIG_OF
+static const struct of_device_id sx932x_of_match[] = {
+       { .compatible = "semtech,sx9320" },
+       { .compatible = "semtech,sx9321" },
+       { .compatible = "semtech,sx9324" },
+       {}
+};
+MODULE_DEVICE_TABLE(of, sx932x_of_match);
+#endif
+static const struct i2c_device_id sx932x_id[] = {
+       { "sx9320", 0 },
+       { "sx9321", 1 },
+       { "sx9324", 2 },
+       {},
+};
+MODULE_DEVICE_TABLE(i2c, sx932x_id);
+
+static struct i2c_driver sx932x_driver = {
+       .driver = {
+               .name   = SX932X_DRIVER_NAME,
+               .acpi_match_table = ACPI_PTR(sx932x_acpi_match),
+               .of_match_table = of_match_ptr(sx932x_of_match),
+               .pm = &sx932x_pm_ops,
+       },
+       .probe          = sx932x_probe,
+       .remove         = sx932x_remove,
+       .id_table       = sx932x_id,
+};
+module_i2c_driver(sx932x_driver);
+
+MODULE_AUTHOR("Enrico Granata <egran...@chromium.org>");
+MODULE_AUTHOR("Gwendal Grignou <gwen...@chromium.org>");
+MODULE_AUTHOR("Pat Plunkett <patplunk...@google.com");
+MODULE_DESCRIPTION("Driver for Semtech SX9320/SX9321/SX9324 proximity sensor");
+MODULE_LICENSE("GPL v2");
-- 
2.19.1.930.g4563a0d9d0-goog

Reply via email to