iio:proximity:sx9324: Add SX9324 support
authorGwendal Grignou <gwendal@chromium.org>
Sat, 1 Jan 2022 20:38:15 +0000 (12:38 -0800)
committerJonathan Cameron <Jonathan.Cameron@huawei.com>
Sun, 23 Jan 2022 18:03:33 +0000 (18:03 +0000)
Semtech SAR sensor SX9324 is an evolution of the SX9310:
It has 4 phases that can be configured to capture and process data
from any of 3 CS pins and provide independent detection:
proximity, table proximity or body proximity.

Gather antenna data:
  echo sx9324-dev3 > trigger/current_trigger
  echo 1 > scan_elements/in_proximity0_en
  echo 1 > buffer/enable
  od -v -An --endian=big -t d2 -w2 /dev/iio\:device3
  (at 10Hz, the default).

Trigger events:
Setting:
  thresh_falling_period: 2 (events)
  thresh_rising_period: 2 (events)
  in_proximity0_thresh_either_value: 300
  in_proximity0_thresh_either_hysteresis: 72

using iio_event_monitor /dev/iio\:deviceX, approaching my hand to the
antenna pad, I see:
...
Event: time: 1634763907532035297, type: proximity, channel: 0, evtype:
thresh, direction: falling
Event: time: 1634763910138104640, type: proximity, channel: 0, evtype:
thresh, direction: rising
...

Datasheet: https://edit.wpgdadawant.com/uploads/news_file/program/2019/30184/tech_files/program_30184_suggest_other_file.pdf
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20220101203817.290512-4-gwendal@chromium.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Documentation/ABI/testing/sysfs-bus-iio-sx9324 [new file with mode: 0644]
drivers/iio/proximity/Kconfig
drivers/iio/proximity/Makefile
drivers/iio/proximity/sx9324.c [new file with mode: 0644]

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-sx9324 b/Documentation/ABI/testing/sysfs-bus-iio-sx9324
new file mode 100644 (file)
index 0000000..632e332
--- /dev/null
@@ -0,0 +1,28 @@
+What:          /sys/bus/iio/devices/iio:deviceX/in_proximity<id>_setup
+Date:          November 2021
+KernelVersion: 5.17
+Contact:       Gwendal Grignou <gwendal@chromium.org>
+Description:
+               SX9324 has 3 inputs, CS0, CS1 and CS2. Hardware layout
+               defines if the input is
+               + not connected (HZ),
+               + grounded (GD),
+               + connected to an antenna where it can act as a base
+                 (DS - data shield), or measured input (MI).
+
+               The sensor rotates measurement across 4 phases
+               (PH0, PH1, PH2, PH3), where the inputs are configured
+               and then measured.
+
+               By default,  during the first phase, [PH0], CS0 is measured,
+               while CS1 and CS2 are used as shields.
+               `cat in_proximity0_setup` returns "MI,DS,DS".
+               [PH1], CS1 is measured, CS0 and CS2 are shield:
+               `cat in_proximity1_setup` returns "DS,MI,DS".
+               [PH2], CS2 is measured, CS0 and CS1 are shield:
+               `cat in_proximity1_setup` returns "DS,DS,MI".
+               [PH3], CS1 and CS2 are measured (combo mode):
+               `cat in_proximity1_setup` returns "DS,MI,MI".
+
+               Note, these are the chip default. Hardware layout will most
+               likely dictate different output. The entry is read-only.
index 0277126..dc66f33 100644 (file)
@@ -131,6 +131,20 @@ config SX9310
          To compile this driver as a module, choose M here: the
          module will be called sx9310.
 
+config SX9324
+       tristate "SX9324 Semtech proximity sensor"
+       select IIO_BUFFER
+       select IIO_TRIGGERED_BUFFER
+       select REGMAP_I2C
+       select SX_COMMON
+       depends on I2C
+       help
+         Say Y here to build a driver for Semtech's SX9324
+         proximity/button sensor.
+
+         To compile this driver as a module, choose M here: the
+         module will be called sx9324.
+
 config SX9500
        tristate "SX9500 Semtech proximity sensor"
        select IIO_BUFFER
index 2577fbc..cffe962 100644 (file)
@@ -14,6 +14,7 @@ obj-$(CONFIG_RFD77402)                += rfd77402.o
 obj-$(CONFIG_SRF04)            += srf04.o
 obj-$(CONFIG_SRF08)            += srf08.o
 obj-$(CONFIG_SX9310)           += sx9310.o
+obj-$(CONFIG_SX9324)           += sx9324.o
 obj-$(CONFIG_SX_COMMON)        += sx_common.o
 obj-$(CONFIG_SX9500)           += sx9500.o
 obj-$(CONFIG_VCNL3020)         += vcnl3020.o
diff --git a/drivers/iio/proximity/sx9324.c b/drivers/iio/proximity/sx9324.c
new file mode 100644 (file)
index 0000000..3aeb34b
--- /dev/null
@@ -0,0 +1,904 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2021 Google LLC.
+ *
+ * Driver for Semtech's SX9324 capacitive proximity/button solution.
+ * Based on SX9324 driver and copy of datasheet at:
+ * https://edit.wpgdadawant.com/uploads/news_file/program/2019/30184/tech_files/program_30184_suggest_other_file.pdf
+ */
+
+#include <linux/acpi.h>
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/log2.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+
+#include <linux/iio/iio.h>
+
+#include "sx_common.h"
+
+/* Register definitions. */
+#define SX9324_REG_IRQ_SRC             SX_COMMON_REG_IRQ_SRC
+#define SX9324_REG_STAT0               0x01
+#define SX9324_REG_STAT1               0x02
+#define SX9324_REG_STAT2               0x03
+#define SX9324_REG_STAT2_COMPSTAT_MASK GENMASK(3, 0)
+#define SX9324_REG_STAT3               0x04
+#define SX9324_REG_IRQ_MSK             0x05
+#define SX9324_CONVDONE_IRQ            BIT(3)
+#define SX9324_FAR_IRQ                 BIT(5)
+#define SX9324_CLOSE_IRQ               BIT(6)
+#define SX9324_REG_IRQ_CFG0            0x06
+#define SX9324_REG_IRQ_CFG1            0x07
+#define SX9324_REG_IRQ_CFG1_FAILCOND    0x80
+#define SX9324_REG_IRQ_CFG2            0x08
+
+#define SX9324_REG_GNRL_CTRL0          0x10
+#define SX9324_REG_GNRL_CTRL0_SCANPERIOD_MASK GENMASK(4, 0)
+#define SX9324_REG_GNRL_CTRL0_SCANPERIOD_100MS 0x16
+#define SX9324_REG_GNRL_CTRL1          0x11
+#define SX9324_REG_GNRL_CTRL1_PHEN_MASK GENMASK(3, 0)
+#define SX9324_REG_GNRL_CTRL1_PAUSECTRL 0x20
+
+#define SX9324_REG_I2C_ADDR            0x14
+#define SX9324_REG_CLK_SPRD            0x15
+
+#define SX9324_REG_AFE_CTRL0           0x20
+#define SX9324_REG_AFE_CTRL1           0x21
+#define SX9324_REG_AFE_CTRL2           0x22
+#define SX9324_REG_AFE_CTRL3           0x23
+#define SX9324_REG_AFE_CTRL4           0x24
+#define SX9324_REG_AFE_CTRL4_FREQ_83_33HZ 0x40
+#define SX9324_REG_AFE_CTRL4_RESOLUTION_MASK GENMASK(2, 0)
+#define SX9324_REG_AFE_CTRL4_RES_100   0x04
+#define SX9324_REG_AFE_CTRL5           0x25
+#define SX9324_REG_AFE_CTRL6           0x26
+#define SX9324_REG_AFE_CTRL7           0x27
+#define SX9324_REG_AFE_PH0             0x28
+#define SX9324_REG_AFE_PH0_PIN_MASK(_pin) \
+       GENMASK(2 * (_pin) + 1, 2 * (_pin))
+
+#define SX9324_REG_AFE_PH1             0x29
+#define SX9324_REG_AFE_PH2             0x2a
+#define SX9324_REG_AFE_PH3             0x2b
+#define SX9324_REG_AFE_CTRL8           0x2c
+#define SX9324_REG_AFE_CTRL8_RESFILTN_4KOHM 0x02
+#define SX9324_REG_AFE_CTRL9           0x2d
+#define SX9324_REG_AFE_CTRL9_AGAIN_1   0x08
+
+#define SX9324_REG_PROX_CTRL0          0x30
+#define SX9324_REG_PROX_CTRL0_GAIN_MASK        GENMASK(5, 3)
+#define SX9324_REG_PROX_CTRL0_GAIN_1           0x80
+#define SX9324_REG_PROX_CTRL0_RAWFILT_1P50     0x01
+#define SX9324_REG_PROX_CTRL1          0x31
+#define SX9324_REG_PROX_CTRL2          0x32
+#define SX9324_REG_PROX_CTRL2_AVGNEG_THRESH_16K 0x20
+#define SX9324_REG_PROX_CTRL3          0x33
+#define SX9324_REG_PROX_CTRL3_AVGDEB_2SAMPLES  0x40
+#define SX9324_REG_PROX_CTRL3_AVGPOS_THRESH_16K 0x20
+#define SX9324_REG_PROX_CTRL4          0x34
+#define SX9324_REG_PROX_CTRL4_AVGNEGFILT_MASK  GENMASK(5, 3)
+#define SX9324_REG_PROX_CTRL4_AVGNEG_FILT_2 0x08
+#define SX9324_REG_PROX_CTRL4_AVGPOSFILT_MASK  GENMASK(2, 0)
+#define SX9324_REG_PROX_CTRL3_AVGPOS_FILT_256 0x04
+#define SX9324_REG_PROX_CTRL5          0x35
+#define SX9324_REG_PROX_CTRL5_HYST_MASK                        GENMASK(5, 4)
+#define SX9324_REG_PROX_CTRL5_CLOSE_DEBOUNCE_MASK      GENMASK(3, 2)
+#define SX9324_REG_PROX_CTRL5_FAR_DEBOUNCE_MASK                GENMASK(1, 0)
+#define SX9324_REG_PROX_CTRL6          0x36
+#define SX9324_REG_PROX_CTRL6_PROXTHRESH_32    0x08
+#define SX9324_REG_PROX_CTRL7          0x37
+
+#define SX9324_REG_ADV_CTRL0           0x40
+#define SX9324_REG_ADV_CTRL1           0x41
+#define SX9324_REG_ADV_CTRL2           0x42
+#define SX9324_REG_ADV_CTRL3           0x43
+#define SX9324_REG_ADV_CTRL4           0x44
+#define SX9324_REG_ADV_CTRL5           0x45
+#define SX9324_REG_ADV_CTRL5_STARTUPSENS_MASK GENMASK(3, 2)
+#define SX9324_REG_ADV_CTRL5_STARTUP_SENSOR_1  0x04
+#define SX9324_REG_ADV_CTRL5_STARTUP_METHOD_1  0x01
+#define SX9324_REG_ADV_CTRL6           0x46
+#define SX9324_REG_ADV_CTRL7           0x47
+#define SX9324_REG_ADV_CTRL8           0x48
+#define SX9324_REG_ADV_CTRL9           0x49
+#define SX9324_REG_ADV_CTRL10          0x4a
+#define SX9324_REG_ADV_CTRL11          0x4b
+#define SX9324_REG_ADV_CTRL12          0x4c
+#define SX9324_REG_ADV_CTRL13          0x4d
+#define SX9324_REG_ADV_CTRL14          0x4e
+#define SX9324_REG_ADV_CTRL15          0x4f
+#define SX9324_REG_ADV_CTRL16          0x50
+#define SX9324_REG_ADV_CTRL17          0x51
+#define SX9324_REG_ADV_CTRL18          0x52
+#define SX9324_REG_ADV_CTRL19          0x53
+#define SX9324_REG_ADV_CTRL20          0x54
+#define SX9324_REG_ADV_CTRL19_HIGHT_FAILURE_THRESH_SATURATION 0xf0
+
+#define SX9324_REG_PHASE_SEL           0x60
+
+#define SX9324_REG_USEFUL_MSB          0x61
+#define SX9324_REG_USEFUL_LSB          0x62
+
+#define SX9324_REG_AVG_MSB             0x63
+#define SX9324_REG_AVG_LSB             0x64
+
+#define SX9324_REG_DIFF_MSB            0x65
+#define SX9324_REG_DIFF_LSB            0x66
+
+#define SX9324_REG_OFFSET_MSB          0x67
+#define SX9324_REG_OFFSET_LSB          0x68
+
+#define SX9324_REG_SAR_MSB             0x69
+#define SX9324_REG_SAR_LSB             0x6a
+
+#define SX9324_REG_RESET               0x9f
+/* Write this to REG_RESET to do a soft reset. */
+#define SX9324_SOFT_RESET              0xde
+
+#define SX9324_REG_WHOAMI              0xfa
+#define   SX9324_WHOAMI_VALUE          0x23
+
+#define SX9324_REG_REVISION            0xfe
+
+/* 4 channels, as defined in STAT0: PH0, PH1, PH2 and PH3. */
+#define SX9324_NUM_CHANNELS            4
+/* 3 CS pins: CS0, CS1, CS2. */
+#define SX9324_NUM_PINS                        3
+
+static const char * const sx9324_cs_pin_usage[] = { "HZ", "MI", "DS", "GD" };
+
+static ssize_t sx9324_phase_configuration_show(struct iio_dev *indio_dev,
+                                              uintptr_t private,
+                                              const struct iio_chan_spec *chan,
+                                              char *buf)
+{
+       struct sx_common_data *data = iio_priv(indio_dev);
+       unsigned int val;
+       int i, ret, pin_idx;
+       size_t len = 0;
+
+       ret = regmap_read(data->regmap, SX9324_REG_AFE_PH0 + chan->channel, &val);
+       if (ret < 0)
+               return ret;
+
+       for (i = 0; i < SX9324_NUM_PINS; i++) {
+               pin_idx = (val & SX9324_REG_AFE_PH0_PIN_MASK(i)) >> (2 * i);
+               len += sysfs_emit_at(buf, len, "%s,",
+                                    sx9324_cs_pin_usage[pin_idx]);
+       }
+       buf[len - 1] = '\n';
+       return len;
+}
+
+static const struct iio_chan_spec_ext_info sx9324_channel_ext_info[] = {
+       {
+               .name = "setup",
+               .shared = IIO_SEPARATE,
+               .read = sx9324_phase_configuration_show,
+       },
+       {}
+};
+
+#define SX9324_CHANNEL(idx)                                     \
+{                                                               \
+       .type = IIO_PROXIMITY,                                   \
+       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |           \
+                             BIT(IIO_CHAN_INFO_HARDWAREGAIN),   \
+       .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+       .info_mask_separate_available =                          \
+               BIT(IIO_CHAN_INFO_HARDWAREGAIN),                 \
+       .info_mask_shared_by_all_available =                     \
+               BIT(IIO_CHAN_INFO_SAMP_FREQ),                    \
+       .indexed = 1,                                            \
+       .channel = idx,                                          \
+       .address = SX9324_REG_DIFF_MSB,                          \
+       .event_spec = sx_common_events,                          \
+       .num_event_specs = ARRAY_SIZE(sx_common_events),         \
+       .scan_index = idx,                                       \
+       .scan_type = {                                           \
+               .sign = 's',                                     \
+               .realbits = 12,                                  \
+               .storagebits = 16,                               \
+               .endianness = IIO_BE,                            \
+       },                                                       \
+       .ext_info = sx9324_channel_ext_info,                     \
+}
+
+static const struct iio_chan_spec sx9324_channels[] = {
+       SX9324_CHANNEL(0),                      /* Phase 0 */
+       SX9324_CHANNEL(1),                      /* Phase 1 */
+       SX9324_CHANNEL(2),                      /* Phase 2 */
+       SX9324_CHANNEL(3),                      /* Phase 3 */
+       IIO_CHAN_SOFT_TIMESTAMP(4),
+};
+
+/*
+ * Each entry contains the integer part (val) and the fractional part, in micro
+ * seconds. It conforms to the IIO output IIO_VAL_INT_PLUS_MICRO.
+ */
+static const struct {
+       int val;
+       int val2;
+} sx9324_samp_freq_table[] = {
+       { 1000, 0 },  /* 00000: Min (no idle time) */
+       { 500, 0 },  /* 00001: 2 ms */
+       { 250, 0 },  /* 00010: 4 ms */
+       { 166, 666666 },  /* 00011: 6 ms */
+       { 125, 0 },  /* 00100: 8 ms */
+       { 100, 0 },  /* 00101: 10 ms */
+       { 71, 428571 },  /* 00110: 14 ms */
+       { 55, 555556 },  /* 00111: 18 ms */
+       { 45, 454545 },  /* 01000: 22 ms */
+       { 38, 461538 },  /* 01001: 26 ms */
+       { 33, 333333 },  /* 01010: 30 ms */
+       { 29, 411765 },  /* 01011: 34 ms */
+       { 26, 315789 },  /* 01100: 38 ms */
+       { 23, 809524 },  /* 01101: 42 ms */
+       { 21, 739130 },  /* 01110: 46 ms */
+       { 20, 0 },  /* 01111: 50 ms */
+       { 17, 857143 },  /* 10000: 56 ms */
+       { 16, 129032 },  /* 10001: 62 ms */
+       { 14, 705882 },  /* 10010: 68 ms */
+       { 13, 513514 },  /* 10011: 74 ms */
+       { 12, 500000 },  /* 10100: 80 ms */
+       { 11, 111111 },  /* 10101: 90 ms */
+       { 10, 0 },  /* 10110: 100 ms (Typ.) */
+       { 5, 0 },  /* 10111: 200 ms */
+       { 3, 333333 },  /* 11000: 300 ms */
+       { 2, 500000 },  /* 11001: 400 ms */
+       { 1, 666667 },  /* 11010: 600 ms */
+       { 1, 250000 },  /* 11011: 800 ms */
+       { 1, 0 },  /* 11100: 1 s */
+       { 0, 500000 },  /* 11101: 2 s */
+       { 0, 333333 },  /* 11110: 3 s */
+       { 0, 250000 },  /* 11111: 4 s */
+};
+
+static const unsigned int sx9324_scan_period_table[] = {
+       2,   15,  30,  45,   60,   90,   120,  200,
+       400, 600, 800, 1000, 2000, 3000, 4000, 5000,
+};
+
+static const struct regmap_range sx9324_writable_reg_ranges[] = {
+       /*
+        * To set COMPSTAT for compensation, even if datasheet says register is
+        * RO.
+        */
+       regmap_reg_range(SX9324_REG_STAT2, SX9324_REG_STAT2),
+       regmap_reg_range(SX9324_REG_IRQ_MSK, SX9324_REG_IRQ_CFG2),
+       regmap_reg_range(SX9324_REG_GNRL_CTRL0, SX9324_REG_GNRL_CTRL1),
+       /* Leave i2c and clock spreading as unavailable */
+       regmap_reg_range(SX9324_REG_AFE_CTRL0, SX9324_REG_AFE_CTRL9),
+       regmap_reg_range(SX9324_REG_PROX_CTRL0, SX9324_REG_PROX_CTRL7),
+       regmap_reg_range(SX9324_REG_ADV_CTRL0, SX9324_REG_ADV_CTRL20),
+       regmap_reg_range(SX9324_REG_PHASE_SEL, SX9324_REG_PHASE_SEL),
+       regmap_reg_range(SX9324_REG_OFFSET_MSB, SX9324_REG_OFFSET_LSB),
+       regmap_reg_range(SX9324_REG_RESET, SX9324_REG_RESET),
+};
+
+static const struct regmap_access_table sx9324_writeable_regs = {
+       .yes_ranges = sx9324_writable_reg_ranges,
+       .n_yes_ranges = ARRAY_SIZE(sx9324_writable_reg_ranges),
+};
+
+/*
+ * All allocated registers are readable, so we just list unallocated
+ * ones.
+ */
+static const struct regmap_range sx9324_non_readable_reg_ranges[] = {
+       regmap_reg_range(SX9324_REG_IRQ_CFG2 + 1, SX9324_REG_GNRL_CTRL0 - 1),
+       regmap_reg_range(SX9324_REG_GNRL_CTRL1 + 1, SX9324_REG_AFE_CTRL0 - 1),
+       regmap_reg_range(SX9324_REG_AFE_CTRL9 + 1, SX9324_REG_PROX_CTRL0 - 1),
+       regmap_reg_range(SX9324_REG_PROX_CTRL7 + 1, SX9324_REG_ADV_CTRL0 - 1),
+       regmap_reg_range(SX9324_REG_ADV_CTRL20 + 1, SX9324_REG_PHASE_SEL - 1),
+       regmap_reg_range(SX9324_REG_SAR_LSB + 1, SX9324_REG_RESET - 1),
+       regmap_reg_range(SX9324_REG_RESET + 1, SX9324_REG_WHOAMI - 1),
+       regmap_reg_range(SX9324_REG_WHOAMI + 1, SX9324_REG_REVISION - 1),
+};
+
+static const struct regmap_access_table sx9324_readable_regs = {
+       .no_ranges = sx9324_non_readable_reg_ranges,
+       .n_no_ranges = ARRAY_SIZE(sx9324_non_readable_reg_ranges),
+};
+
+static const struct regmap_range sx9324_volatile_reg_ranges[] = {
+       regmap_reg_range(SX9324_REG_IRQ_SRC, SX9324_REG_STAT3),
+       regmap_reg_range(SX9324_REG_USEFUL_MSB, SX9324_REG_DIFF_LSB),
+       regmap_reg_range(SX9324_REG_SAR_MSB, SX9324_REG_SAR_LSB),
+       regmap_reg_range(SX9324_REG_WHOAMI, SX9324_REG_WHOAMI),
+       regmap_reg_range(SX9324_REG_REVISION, SX9324_REG_REVISION),
+};
+
+static const struct regmap_access_table sx9324_volatile_regs = {
+       .yes_ranges = sx9324_volatile_reg_ranges,
+       .n_yes_ranges = ARRAY_SIZE(sx9324_volatile_reg_ranges),
+};
+
+static const struct regmap_config sx9324_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 8,
+
+       .max_register = SX9324_REG_REVISION,
+       .cache_type = REGCACHE_RBTREE,
+
+       .wr_table = &sx9324_writeable_regs,
+       .rd_table = &sx9324_readable_regs,
+       .volatile_table = &sx9324_volatile_regs,
+};
+
+static int sx9324_read_prox_data(struct sx_common_data *data,
+                                const struct iio_chan_spec *chan,
+                                __be16 *val)
+{
+       int ret;
+
+       ret = regmap_write(data->regmap, SX9324_REG_PHASE_SEL, chan->channel);
+       if (ret < 0)
+               return ret;
+
+       return regmap_bulk_read(data->regmap, chan->address, val, sizeof(*val));
+}
+
+/*
+ * If we have no interrupt support, we have to wait for a scan period
+ * after enabling a channel to get a result.
+ */
+static int sx9324_wait_for_sample(struct sx_common_data *data)
+{
+       int ret;
+       unsigned int val;
+
+       ret = regmap_read(data->regmap, SX9324_REG_GNRL_CTRL0, &val);
+       if (ret < 0)
+               return ret;
+       val = FIELD_GET(SX9324_REG_GNRL_CTRL0_SCANPERIOD_MASK, val);
+
+       msleep(sx9324_scan_period_table[val]);
+
+       return 0;
+}
+
+static int sx9324_read_gain(struct sx_common_data *data,
+                           const struct iio_chan_spec *chan, int *val)
+{
+       unsigned int reg, regval;
+       int ret;
+
+       reg = SX9324_REG_PROX_CTRL0 + chan->channel / 2;
+       ret = regmap_read(data->regmap, reg, &regval);
+       if (ret)
+               return ret;
+
+       *val = 1 << FIELD_GET(SX9324_REG_PROX_CTRL0_GAIN_MASK, regval);
+
+       return IIO_VAL_INT;
+}
+
+static int sx9324_read_samp_freq(struct sx_common_data *data,
+                                int *val, int *val2)
+{
+       int ret;
+       unsigned int regval;
+
+       ret = regmap_read(data->regmap, SX9324_REG_GNRL_CTRL0, &regval);
+       if (ret)
+               return ret;
+
+       regval = FIELD_GET(SX9324_REG_GNRL_CTRL0_SCANPERIOD_MASK, regval);
+       *val = sx9324_samp_freq_table[regval].val;
+       *val2 = sx9324_samp_freq_table[regval].val2;
+
+       return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int sx9324_read_raw(struct iio_dev *indio_dev,
+                          const struct iio_chan_spec *chan,
+                          int *val, int *val2, long mask)
+{
+       struct sx_common_data *data = iio_priv(indio_dev);
+       int ret;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+               ret = iio_device_claim_direct_mode(indio_dev);
+               if (ret)
+                       return ret;
+
+               ret = sx_common_read_proximity(data, chan, val);
+               iio_device_release_direct_mode(indio_dev);
+               return ret;
+       case IIO_CHAN_INFO_HARDWAREGAIN:
+               ret = iio_device_claim_direct_mode(indio_dev);
+               if (ret)
+                       return ret;
+
+               ret = sx9324_read_gain(data, chan, val);
+               iio_device_release_direct_mode(indio_dev);
+               return ret;
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               return sx9324_read_samp_freq(data, val, val2);
+       default:
+               return -EINVAL;
+       }
+}
+
+static const int sx9324_gain_vals[] = { 1, 2, 4, 8 };
+
+static int sx9324_read_avail(struct iio_dev *indio_dev,
+                            struct iio_chan_spec const *chan,
+                            const int **vals, int *type, int *length,
+                            long mask)
+{
+       if (chan->type != IIO_PROXIMITY)
+               return -EINVAL;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_HARDWAREGAIN:
+               *type = IIO_VAL_INT;
+               *length = ARRAY_SIZE(sx9324_gain_vals);
+               *vals = sx9324_gain_vals;
+               return IIO_AVAIL_LIST;
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               *type = IIO_VAL_INT_PLUS_MICRO;
+               *length = ARRAY_SIZE(sx9324_samp_freq_table) * 2;
+               *vals = (int *)sx9324_samp_freq_table;
+               return IIO_AVAIL_LIST;
+       default:
+               return -EINVAL;
+       }
+}
+
+static int sx9324_set_samp_freq(struct sx_common_data *data,
+                               int val, int val2)
+{
+       int i, ret;
+
+       for (i = 0; i < ARRAY_SIZE(sx9324_samp_freq_table); i++)
+               if (val == sx9324_samp_freq_table[i].val &&
+                   val2 == sx9324_samp_freq_table[i].val2)
+                       break;
+
+       if (i == ARRAY_SIZE(sx9324_samp_freq_table))
+               return -EINVAL;
+
+       mutex_lock(&data->mutex);
+
+       ret = regmap_update_bits(data->regmap,
+                                SX9324_REG_GNRL_CTRL0,
+                                SX9324_REG_GNRL_CTRL0_SCANPERIOD_MASK, i);
+
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int sx9324_read_thresh(struct sx_common_data *data,
+                             const struct iio_chan_spec *chan, int *val)
+{
+       unsigned int regval;
+       unsigned int reg;
+       int ret;
+
+       /*
+        * TODO(gwendal): Depending on the phase function
+        * (proximity/table/body), retrieve the right threshold.
+        * For now, return the proximity threshold.
+        */
+       reg = SX9324_REG_PROX_CTRL6 + chan->channel / 2;
+       ret = regmap_read(data->regmap, reg, &regval);
+       if (ret)
+               return ret;
+
+       if (regval <= 1)
+               *val = regval;
+       else
+               *val = (regval * regval) / 2;
+
+       return IIO_VAL_INT;
+}
+
+static int sx9324_read_hysteresis(struct sx_common_data *data,
+                                 const struct iio_chan_spec *chan, int *val)
+{
+       unsigned int regval, pthresh;
+       int ret;
+
+       ret = sx9324_read_thresh(data, chan, &pthresh);
+       if (ret < 0)
+               return ret;
+
+       ret = regmap_read(data->regmap, SX9324_REG_PROX_CTRL5, &regval);
+       if (ret)
+               return ret;
+
+       regval = FIELD_GET(SX9324_REG_PROX_CTRL5_HYST_MASK, regval);
+       if (!regval)
+               *val = 0;
+       else
+               *val = pthresh >> (5 - regval);
+
+       return IIO_VAL_INT;
+}
+
+static int sx9324_read_far_debounce(struct sx_common_data *data, int *val)
+{
+       unsigned int regval;
+       int ret;
+
+       ret = regmap_read(data->regmap, SX9324_REG_PROX_CTRL5, &regval);
+       if (ret)
+               return ret;
+
+       regval = FIELD_GET(SX9324_REG_PROX_CTRL5_FAR_DEBOUNCE_MASK, regval);
+       if (regval)
+               *val = 1 << regval;
+       else
+               *val = 0;
+
+       return IIO_VAL_INT;
+}
+
+static int sx9324_read_close_debounce(struct sx_common_data *data, int *val)
+{
+       unsigned int regval;
+       int ret;
+
+       ret = regmap_read(data->regmap, SX9324_REG_PROX_CTRL5, &regval);
+       if (ret)
+               return ret;
+
+       regval = FIELD_GET(SX9324_REG_PROX_CTRL5_CLOSE_DEBOUNCE_MASK, regval);
+       if (regval)
+               *val = 1 << regval;
+       else
+               *val = 0;
+
+       return IIO_VAL_INT;
+}
+
+static int sx9324_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 sx_common_data *data = iio_priv(indio_dev);
+
+       if (chan->type != IIO_PROXIMITY)
+               return -EINVAL;
+
+       switch (info) {
+       case IIO_EV_INFO_VALUE:
+               return sx9324_read_thresh(data, chan, val);
+       case IIO_EV_INFO_PERIOD:
+               switch (dir) {
+               case IIO_EV_DIR_RISING:
+                       return sx9324_read_far_debounce(data, val);
+               case IIO_EV_DIR_FALLING:
+                       return sx9324_read_close_debounce(data, val);
+               default:
+                       return -EINVAL;
+               }
+       case IIO_EV_INFO_HYSTERESIS:
+               return sx9324_read_hysteresis(data, chan, val);
+       default:
+               return -EINVAL;
+       }
+}
+
+static int sx9324_write_thresh(struct sx_common_data *data,
+                              const struct iio_chan_spec *chan, int _val)
+{
+       unsigned int reg, val = _val;
+       int ret;
+
+       reg = SX9324_REG_PROX_CTRL6 + chan->channel / 2;
+
+       if (val >= 1)
+               val = int_sqrt(2 * val);
+
+       if (val > 0xff)
+               return -EINVAL;
+
+       mutex_lock(&data->mutex);
+       ret = regmap_write(data->regmap, reg, val);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int sx9324_write_hysteresis(struct sx_common_data *data,
+                                  const struct iio_chan_spec *chan, int _val)
+{
+       unsigned int hyst, val = _val;
+       int ret, pthresh;
+
+       ret = sx9324_read_thresh(data, chan, &pthresh);
+       if (ret < 0)
+               return ret;
+
+       if (val == 0)
+               hyst = 0;
+       else if (val >= pthresh >> 2)
+               hyst = 3;
+       else if (val >= pthresh >> 3)
+               hyst = 2;
+       else if (val >= pthresh >> 4)
+               hyst = 1;
+       else
+               return -EINVAL;
+
+       hyst = FIELD_PREP(SX9324_REG_PROX_CTRL5_HYST_MASK, hyst);
+       mutex_lock(&data->mutex);
+       ret = regmap_update_bits(data->regmap, SX9324_REG_PROX_CTRL5,
+                                SX9324_REG_PROX_CTRL5_HYST_MASK, hyst);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int sx9324_write_far_debounce(struct sx_common_data *data, int _val)
+{
+       unsigned int regval, val = _val;
+       int ret;
+
+       if (val > 0)
+               val = ilog2(val);
+       if (!FIELD_FIT(SX9324_REG_PROX_CTRL5_FAR_DEBOUNCE_MASK, val))
+               return -EINVAL;
+
+       regval = FIELD_PREP(SX9324_REG_PROX_CTRL5_FAR_DEBOUNCE_MASK, val);
+
+       mutex_lock(&data->mutex);
+       ret = regmap_update_bits(data->regmap, SX9324_REG_PROX_CTRL5,
+                                SX9324_REG_PROX_CTRL5_FAR_DEBOUNCE_MASK,
+                                regval);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int sx9324_write_close_debounce(struct sx_common_data *data, int _val)
+{
+       unsigned int regval, val = _val;
+       int ret;
+
+       if (val > 0)
+               val = ilog2(val);
+       if (!FIELD_FIT(SX9324_REG_PROX_CTRL5_CLOSE_DEBOUNCE_MASK, val))
+               return -EINVAL;
+
+       regval = FIELD_PREP(SX9324_REG_PROX_CTRL5_CLOSE_DEBOUNCE_MASK, val);
+
+       mutex_lock(&data->mutex);
+       ret = regmap_update_bits(data->regmap, SX9324_REG_PROX_CTRL5,
+                                SX9324_REG_PROX_CTRL5_CLOSE_DEBOUNCE_MASK,
+                                regval);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int sx9324_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 sx_common_data *data = iio_priv(indio_dev);
+
+       if (chan->type != IIO_PROXIMITY)
+               return -EINVAL;
+
+       switch (info) {
+       case IIO_EV_INFO_VALUE:
+               return sx9324_write_thresh(data, chan, val);
+       case IIO_EV_INFO_PERIOD:
+               switch (dir) {
+               case IIO_EV_DIR_RISING:
+                       return sx9324_write_far_debounce(data, val);
+               case IIO_EV_DIR_FALLING:
+                       return sx9324_write_close_debounce(data, val);
+               default:
+                       return -EINVAL;
+               }
+       case IIO_EV_INFO_HYSTERESIS:
+               return sx9324_write_hysteresis(data, chan, val);
+       default:
+               return -EINVAL;
+       }
+}
+
+static int sx9324_write_gain(struct sx_common_data *data,
+                            const struct iio_chan_spec *chan, int val)
+{
+       unsigned int gain, reg;
+       int ret;
+
+       gain = ilog2(val);
+       reg = SX9324_REG_PROX_CTRL0 + chan->channel / 2;
+       gain = FIELD_PREP(SX9324_REG_PROX_CTRL0_GAIN_MASK, gain);
+
+       mutex_lock(&data->mutex);
+       ret = regmap_update_bits(data->regmap, reg,
+                                SX9324_REG_PROX_CTRL0_GAIN_MASK,
+                                gain);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int sx9324_write_raw(struct iio_dev *indio_dev,
+                           const struct iio_chan_spec *chan, int val, int val2,
+                           long mask)
+{
+       struct sx_common_data *data = iio_priv(indio_dev);
+
+       switch (mask) {
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               return sx9324_set_samp_freq(data, val, val2);
+       case IIO_CHAN_INFO_HARDWAREGAIN:
+               return sx9324_write_gain(data, chan, val);
+       default:
+               return -EINVAL;
+       }
+}
+
+/* Activate all channels and perform an initial compensation. */
+static int sx9324_init_compensation(struct iio_dev *indio_dev)
+{
+       struct sx_common_data *data = iio_priv(indio_dev);
+       unsigned int val;
+       int ret;
+
+       /* run the compensation phase on all channels */
+       ret = regmap_update_bits(data->regmap, SX9324_REG_STAT2,
+                                SX9324_REG_STAT2_COMPSTAT_MASK,
+                                SX9324_REG_STAT2_COMPSTAT_MASK);
+       if (ret)
+               return ret;
+
+       return regmap_read_poll_timeout(data->regmap, SX9324_REG_STAT2, val,
+                                       !(val & SX9324_REG_STAT2_COMPSTAT_MASK),
+                                       20000, 2000000);
+}
+
+static int sx9324_check_whoami(struct device *dev,
+                              struct iio_dev *indio_dev)
+{
+       /*
+        * Only one sensor for this driver. Assuming the device tree
+        * is correct, just set the sensor name.
+        */
+       indio_dev->name = "sx9324";
+       return 0;
+}
+
+static const struct sx_common_chip_info sx9324_chip_info = {
+       .reg_stat = SX9324_REG_STAT0,
+       .reg_irq_msk = SX9324_REG_IRQ_MSK,
+       .reg_enable_chan = SX9324_REG_GNRL_CTRL1,
+       .reg_reset = SX9324_REG_RESET,
+
+       .mask_enable_chan = SX9324_REG_GNRL_CTRL1_PHEN_MASK,
+       .irq_msk_offset = 3,
+       .num_channels = SX9324_NUM_CHANNELS,
+
+       .ops = {
+               .read_prox_data = sx9324_read_prox_data,
+               .check_whoami = sx9324_check_whoami,
+               .init_compensation = sx9324_init_compensation,
+               .wait_for_sample = sx9324_wait_for_sample,
+       },
+
+       .iio_channels = sx9324_channels,
+       .num_iio_channels = ARRAY_SIZE(sx9324_channels),
+       .iio_info =  {
+               .read_raw = sx9324_read_raw,
+               .read_avail = sx9324_read_avail,
+               .read_event_value = sx9324_read_event_val,
+               .write_event_value = sx9324_write_event_val,
+               .write_raw = sx9324_write_raw,
+               .read_event_config = sx_common_read_event_config,
+               .write_event_config = sx_common_write_event_config,
+       },
+};
+
+static int sx9324_probe(struct i2c_client *client)
+{
+       return sx_common_probe(client, &sx9324_chip_info, &sx9324_regmap_config);
+}
+
+static int __maybe_unused sx9324_suspend(struct device *dev)
+{
+       struct sx_common_data *data = iio_priv(dev_get_drvdata(dev));
+       unsigned int regval;
+       int ret;
+
+       disable_irq_nosync(data->client->irq);
+
+       mutex_lock(&data->mutex);
+       ret = regmap_read(data->regmap, SX9324_REG_GNRL_CTRL1, &regval);
+
+       data->suspend_ctrl =
+               FIELD_GET(SX9324_REG_GNRL_CTRL1_PHEN_MASK, regval);
+
+       if (ret < 0)
+               goto out;
+
+       /* Disable all phases, send the device to sleep. */
+       ret = regmap_write(data->regmap, SX9324_REG_GNRL_CTRL1, 0);
+
+out:
+       mutex_unlock(&data->mutex);
+       return ret;
+}
+
+static int __maybe_unused sx9324_resume(struct device *dev)
+{
+       struct sx_common_data *data = iio_priv(dev_get_drvdata(dev));
+       int ret;
+
+       mutex_lock(&data->mutex);
+       ret = regmap_write(data->regmap, SX9324_REG_GNRL_CTRL1,
+                          data->suspend_ctrl | SX9324_REG_GNRL_CTRL1_PAUSECTRL);
+       mutex_unlock(&data->mutex);
+       if (ret)
+               return ret;
+
+       enable_irq(data->client->irq);
+       return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(sx9324_pm_ops, sx9324_suspend, sx9324_resume);
+
+static const struct acpi_device_id sx9324_acpi_match[] = {
+       { "STH9324", SX9324_WHOAMI_VALUE },
+       { }
+};
+MODULE_DEVICE_TABLE(acpi, sx9324_acpi_match);
+
+static const struct of_device_id sx9324_of_match[] = {
+       { .compatible = "semtech,sx9324", (void *)SX9324_WHOAMI_VALUE },
+       { }
+};
+MODULE_DEVICE_TABLE(of, sx9324_of_match);
+
+static const struct i2c_device_id sx9324_id[] = {
+       { "sx9324", SX9324_WHOAMI_VALUE },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, sx9324_id);
+
+static struct i2c_driver sx9324_driver = {
+       .driver = {
+               .name   = "sx9324",
+               .acpi_match_table = sx9324_acpi_match,
+               .of_match_table = sx9324_of_match,
+               .pm = &sx9324_pm_ops,
+
+               /*
+                * Lots of i2c transfers in probe + over 200 ms waiting in
+                * sx9324_init_compensation() mean a slow probe; prefer async
+                * so we don't delay boot if we're builtin to the kernel.
+                */
+               .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+       },
+       .probe_new      = sx9324_probe,
+       .id_table       = sx9324_id,
+};
+module_i2c_driver(sx9324_driver);
+
+MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");
+MODULE_DESCRIPTION("Driver for Semtech SX9324 proximity sensor");
+MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS(SEMTECH_PROX);