v4.19.13 snapshot.
diff --git a/drivers/iio/light/max44000.c b/drivers/iio/light/max44000.c
new file mode 100644
index 0000000..bcdb0eb
--- /dev/null
+++ b/drivers/iio/light/max44000.c
@@ -0,0 +1,639 @@
+/*
+ * MAX44000 Ambient and Infrared Proximity Sensor
+ *
+ * Copyright (c) 2016, Intel Corporation.
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License. See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * Data sheet: https://datasheets.maximintegrated.com/en/ds/MAX44000.pdf
+ *
+ * 7-bit I2C slave address 0x4a
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/util_macros.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/acpi.h>
+
+#define MAX44000_DRV_NAME "max44000"
+
+/* Registers in datasheet order */
+#define MAX44000_REG_STATUS 0x00
+#define MAX44000_REG_CFG_MAIN 0x01
+#define MAX44000_REG_CFG_RX 0x02
+#define MAX44000_REG_CFG_TX 0x03
+#define MAX44000_REG_ALS_DATA_HI 0x04
+#define MAX44000_REG_ALS_DATA_LO 0x05
+#define MAX44000_REG_PRX_DATA 0x16
+#define MAX44000_REG_ALS_UPTHR_HI 0x06
+#define MAX44000_REG_ALS_UPTHR_LO 0x07
+#define MAX44000_REG_ALS_LOTHR_HI 0x08
+#define MAX44000_REG_ALS_LOTHR_LO 0x09
+#define MAX44000_REG_PST 0x0a
+#define MAX44000_REG_PRX_IND 0x0b
+#define MAX44000_REG_PRX_THR 0x0c
+#define MAX44000_REG_TRIM_GAIN_GREEN 0x0f
+#define MAX44000_REG_TRIM_GAIN_IR 0x10
+
+/* REG_CFG bits */
+#define MAX44000_CFG_ALSINTE 0x01
+#define MAX44000_CFG_PRXINTE 0x02
+#define MAX44000_CFG_MASK 0x1c
+#define MAX44000_CFG_MODE_SHUTDOWN 0x00
+#define MAX44000_CFG_MODE_ALS_GIR 0x04
+#define MAX44000_CFG_MODE_ALS_G 0x08
+#define MAX44000_CFG_MODE_ALS_IR 0x0c
+#define MAX44000_CFG_MODE_ALS_PRX 0x10
+#define MAX44000_CFG_MODE_PRX 0x14
+#define MAX44000_CFG_TRIM 0x20
+
+/*
+ * Upper 4 bits are not documented but start as 1 on powerup
+ * Setting them to 0 causes proximity to misbehave so set them to 1
+ */
+#define MAX44000_REG_CFG_RX_DEFAULT 0xf0
+
+/* REG_RX bits */
+#define MAX44000_CFG_RX_ALSTIM_MASK 0x0c
+#define MAX44000_CFG_RX_ALSTIM_SHIFT 2
+#define MAX44000_CFG_RX_ALSPGA_MASK 0x03
+#define MAX44000_CFG_RX_ALSPGA_SHIFT 0
+
+/* REG_TX bits */
+#define MAX44000_LED_CURRENT_MASK 0xf
+#define MAX44000_LED_CURRENT_MAX 11
+#define MAX44000_LED_CURRENT_DEFAULT 6
+
+#define MAX44000_ALSDATA_OVERFLOW 0x4000
+
+struct max44000_data {
+ struct mutex lock;
+ struct regmap *regmap;
+};
+
+/* Default scale is set to the minimum of 0.03125 or 1 / (1 << 5) lux */
+#define MAX44000_ALS_TO_LUX_DEFAULT_FRACTION_LOG2 5
+
+/* Scale can be multiplied by up to 128x via ALSPGA for measurement gain */
+static const int max44000_alspga_shift[] = {0, 2, 4, 7};
+#define MAX44000_ALSPGA_MAX_SHIFT 7
+
+/*
+ * Scale can be multiplied by up to 64x via ALSTIM because of lost resolution
+ *
+ * This scaling factor is hidden from userspace and instead accounted for when
+ * reading raw values from the device.
+ *
+ * This makes it possible to cleanly expose ALSPGA as IIO_CHAN_INFO_SCALE and
+ * ALSTIM as IIO_CHAN_INFO_INT_TIME without the values affecting each other.
+ *
+ * Handling this internally is also required for buffer support because the
+ * channel's scan_type can't be modified dynamically.
+ */
+static const int max44000_alstim_shift[] = {0, 2, 4, 6};
+#define MAX44000_ALSTIM_SHIFT(alstim) (2 * (alstim))
+
+/* Available integration times with pretty manual alignment: */
+static const int max44000_int_time_avail_ns_array[] = {
+ 100000000,
+ 25000000,
+ 6250000,
+ 1562500,
+};
+static const char max44000_int_time_avail_str[] =
+ "0.100 "
+ "0.025 "
+ "0.00625 "
+ "0.0015625";
+
+/* Available scales (internal to ulux) with pretty manual alignment: */
+static const int max44000_scale_avail_ulux_array[] = {
+ 31250,
+ 125000,
+ 500000,
+ 4000000,
+};
+static const char max44000_scale_avail_str[] =
+ "0.03125 "
+ "0.125 "
+ "0.5 "
+ "4";
+
+#define MAX44000_SCAN_INDEX_ALS 0
+#define MAX44000_SCAN_INDEX_PRX 1
+
+static const struct iio_chan_spec max44000_channels[] = {
+ {
+ .type = IIO_LIGHT,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_INT_TIME),
+ .scan_index = MAX44000_SCAN_INDEX_ALS,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 14,
+ .storagebits = 16,
+ }
+ },
+ {
+ .type = IIO_PROXIMITY,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .scan_index = MAX44000_SCAN_INDEX_PRX,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 8,
+ .storagebits = 16,
+ }
+ },
+ IIO_CHAN_SOFT_TIMESTAMP(2),
+ {
+ .type = IIO_CURRENT,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .extend_name = "led",
+ .output = 1,
+ .scan_index = -1,
+ },
+};
+
+static int max44000_read_alstim(struct max44000_data *data)
+{
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(data->regmap, MAX44000_REG_CFG_RX, &val);
+ if (ret < 0)
+ return ret;
+ return (val & MAX44000_CFG_RX_ALSTIM_MASK) >> MAX44000_CFG_RX_ALSTIM_SHIFT;
+}
+
+static int max44000_write_alstim(struct max44000_data *data, int val)
+{
+ return regmap_write_bits(data->regmap, MAX44000_REG_CFG_RX,
+ MAX44000_CFG_RX_ALSTIM_MASK,
+ val << MAX44000_CFG_RX_ALSTIM_SHIFT);
+}
+
+static int max44000_read_alspga(struct max44000_data *data)
+{
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(data->regmap, MAX44000_REG_CFG_RX, &val);
+ if (ret < 0)
+ return ret;
+ return (val & MAX44000_CFG_RX_ALSPGA_MASK) >> MAX44000_CFG_RX_ALSPGA_SHIFT;
+}
+
+static int max44000_write_alspga(struct max44000_data *data, int val)
+{
+ return regmap_write_bits(data->regmap, MAX44000_REG_CFG_RX,
+ MAX44000_CFG_RX_ALSPGA_MASK,
+ val << MAX44000_CFG_RX_ALSPGA_SHIFT);
+}
+
+static int max44000_read_alsval(struct max44000_data *data)
+{
+ u16 regval;
+ __be16 val;
+ int alstim, ret;
+
+ ret = regmap_bulk_read(data->regmap, MAX44000_REG_ALS_DATA_HI,
+ &val, sizeof(val));
+ if (ret < 0)
+ return ret;
+ alstim = ret = max44000_read_alstim(data);
+ if (ret < 0)
+ return ret;
+
+ regval = be16_to_cpu(val);
+
+ /*
+ * Overflow is explained on datasheet page 17.
+ *
+ * It's a warning that either the G or IR channel has become saturated
+ * and that the value in the register is likely incorrect.
+ *
+ * The recommendation is to change the scale (ALSPGA).
+ * The driver just returns the max representable value.
+ */
+ if (regval & MAX44000_ALSDATA_OVERFLOW)
+ return 0x3FFF;
+
+ return regval << MAX44000_ALSTIM_SHIFT(alstim);
+}
+
+static int max44000_write_led_current_raw(struct max44000_data *data, int val)
+{
+ /* Maybe we should clamp the value instead? */
+ if (val < 0 || val > MAX44000_LED_CURRENT_MAX)
+ return -ERANGE;
+ if (val >= 8)
+ val += 4;
+ return regmap_write_bits(data->regmap, MAX44000_REG_CFG_TX,
+ MAX44000_LED_CURRENT_MASK, val);
+}
+
+static int max44000_read_led_current_raw(struct max44000_data *data)
+{
+ unsigned int regval;
+ int ret;
+
+ ret = regmap_read(data->regmap, MAX44000_REG_CFG_TX, ®val);
+ if (ret < 0)
+ return ret;
+ regval &= MAX44000_LED_CURRENT_MASK;
+ if (regval >= 8)
+ regval -= 4;
+ return regval;
+}
+
+static int max44000_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct max44000_data *data = iio_priv(indio_dev);
+ int alstim, alspga;
+ unsigned int regval;
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ switch (chan->type) {
+ case IIO_LIGHT:
+ mutex_lock(&data->lock);
+ ret = max44000_read_alsval(data);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+
+ case IIO_PROXIMITY:
+ mutex_lock(&data->lock);
+ ret = regmap_read(data->regmap, MAX44000_REG_PRX_DATA, ®val);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ return ret;
+ *val = regval;
+ return IIO_VAL_INT;
+
+ case IIO_CURRENT:
+ mutex_lock(&data->lock);
+ ret = max44000_read_led_current_raw(data);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_CURRENT:
+ /* Output register is in 10s of miliamps */
+ *val = 10;
+ return IIO_VAL_INT;
+
+ case IIO_LIGHT:
+ mutex_lock(&data->lock);
+ alspga = ret = max44000_read_alspga(data);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ return ret;
+
+ /* Avoid negative shifts */
+ *val = (1 << MAX44000_ALSPGA_MAX_SHIFT);
+ *val2 = MAX44000_ALS_TO_LUX_DEFAULT_FRACTION_LOG2
+ + MAX44000_ALSPGA_MAX_SHIFT
+ - max44000_alspga_shift[alspga];
+ return IIO_VAL_FRACTIONAL_LOG2;
+
+ default:
+ return -EINVAL;
+ }
+
+ case IIO_CHAN_INFO_INT_TIME:
+ mutex_lock(&data->lock);
+ alstim = ret = max44000_read_alstim(data);
+ mutex_unlock(&data->lock);
+
+ if (ret < 0)
+ return ret;
+ *val = 0;
+ *val2 = max44000_int_time_avail_ns_array[alstim];
+ return IIO_VAL_INT_PLUS_NANO;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int max44000_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct max44000_data *data = iio_priv(indio_dev);
+ int ret;
+
+ if (mask == IIO_CHAN_INFO_RAW && chan->type == IIO_CURRENT) {
+ mutex_lock(&data->lock);
+ ret = max44000_write_led_current_raw(data, val);
+ mutex_unlock(&data->lock);
+ return ret;
+ } else if (mask == IIO_CHAN_INFO_INT_TIME && chan->type == IIO_LIGHT) {
+ s64 valns = val * NSEC_PER_SEC + val2;
+ int alstim = find_closest_descending(valns,
+ max44000_int_time_avail_ns_array,
+ ARRAY_SIZE(max44000_int_time_avail_ns_array));
+ mutex_lock(&data->lock);
+ ret = max44000_write_alstim(data, alstim);
+ mutex_unlock(&data->lock);
+ return ret;
+ } else if (mask == IIO_CHAN_INFO_SCALE && chan->type == IIO_LIGHT) {
+ s64 valus = val * USEC_PER_SEC + val2;
+ int alspga = find_closest(valus,
+ max44000_scale_avail_ulux_array,
+ ARRAY_SIZE(max44000_scale_avail_ulux_array));
+ mutex_lock(&data->lock);
+ ret = max44000_write_alspga(data, alspga);
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+
+ return -EINVAL;
+}
+
+static int max44000_write_raw_get_fmt(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ long mask)
+{
+ if (mask == IIO_CHAN_INFO_INT_TIME && chan->type == IIO_LIGHT)
+ return IIO_VAL_INT_PLUS_NANO;
+ else if (mask == IIO_CHAN_INFO_SCALE && chan->type == IIO_LIGHT)
+ return IIO_VAL_INT_PLUS_MICRO;
+ else
+ return IIO_VAL_INT;
+}
+
+static IIO_CONST_ATTR(illuminance_integration_time_available, max44000_int_time_avail_str);
+static IIO_CONST_ATTR(illuminance_scale_available, max44000_scale_avail_str);
+
+static struct attribute *max44000_attributes[] = {
+ &iio_const_attr_illuminance_integration_time_available.dev_attr.attr,
+ &iio_const_attr_illuminance_scale_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group max44000_attribute_group = {
+ .attrs = max44000_attributes,
+};
+
+static const struct iio_info max44000_info = {
+ .read_raw = max44000_read_raw,
+ .write_raw = max44000_write_raw,
+ .write_raw_get_fmt = max44000_write_raw_get_fmt,
+ .attrs = &max44000_attribute_group,
+};
+
+static bool max44000_readable_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case MAX44000_REG_STATUS:
+ case MAX44000_REG_CFG_MAIN:
+ case MAX44000_REG_CFG_RX:
+ case MAX44000_REG_CFG_TX:
+ case MAX44000_REG_ALS_DATA_HI:
+ case MAX44000_REG_ALS_DATA_LO:
+ case MAX44000_REG_PRX_DATA:
+ case MAX44000_REG_ALS_UPTHR_HI:
+ case MAX44000_REG_ALS_UPTHR_LO:
+ case MAX44000_REG_ALS_LOTHR_HI:
+ case MAX44000_REG_ALS_LOTHR_LO:
+ case MAX44000_REG_PST:
+ case MAX44000_REG_PRX_IND:
+ case MAX44000_REG_PRX_THR:
+ case MAX44000_REG_TRIM_GAIN_GREEN:
+ case MAX44000_REG_TRIM_GAIN_IR:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static bool max44000_writeable_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case MAX44000_REG_CFG_MAIN:
+ case MAX44000_REG_CFG_RX:
+ case MAX44000_REG_CFG_TX:
+ case MAX44000_REG_ALS_UPTHR_HI:
+ case MAX44000_REG_ALS_UPTHR_LO:
+ case MAX44000_REG_ALS_LOTHR_HI:
+ case MAX44000_REG_ALS_LOTHR_LO:
+ case MAX44000_REG_PST:
+ case MAX44000_REG_PRX_IND:
+ case MAX44000_REG_PRX_THR:
+ case MAX44000_REG_TRIM_GAIN_GREEN:
+ case MAX44000_REG_TRIM_GAIN_IR:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static bool max44000_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case MAX44000_REG_STATUS:
+ case MAX44000_REG_ALS_DATA_HI:
+ case MAX44000_REG_ALS_DATA_LO:
+ case MAX44000_REG_PRX_DATA:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static bool max44000_precious_reg(struct device *dev, unsigned int reg)
+{
+ return reg == MAX44000_REG_STATUS;
+}
+
+static const struct regmap_config max44000_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+
+ .max_register = MAX44000_REG_PRX_DATA,
+ .readable_reg = max44000_readable_reg,
+ .writeable_reg = max44000_writeable_reg,
+ .volatile_reg = max44000_volatile_reg,
+ .precious_reg = max44000_precious_reg,
+
+ .use_single_rw = 1,
+ .cache_type = REGCACHE_RBTREE,
+};
+
+static irqreturn_t max44000_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct max44000_data *data = iio_priv(indio_dev);
+ u16 buf[8]; /* 2x u16 + padding + 8 bytes timestamp */
+ int index = 0;
+ unsigned int regval;
+ int ret;
+
+ mutex_lock(&data->lock);
+ if (test_bit(MAX44000_SCAN_INDEX_ALS, indio_dev->active_scan_mask)) {
+ ret = max44000_read_alsval(data);
+ if (ret < 0)
+ goto out_unlock;
+ buf[index++] = ret;
+ }
+ if (test_bit(MAX44000_SCAN_INDEX_PRX, indio_dev->active_scan_mask)) {
+ ret = regmap_read(data->regmap, MAX44000_REG_PRX_DATA, ®val);
+ if (ret < 0)
+ goto out_unlock;
+ buf[index] = regval;
+ }
+ mutex_unlock(&data->lock);
+
+ iio_push_to_buffers_with_timestamp(indio_dev, buf,
+ iio_get_time_ns(indio_dev));
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
+
+out_unlock:
+ mutex_unlock(&data->lock);
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
+}
+
+static int max44000_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct max44000_data *data;
+ struct iio_dev *indio_dev;
+ int ret, reg;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+ data = iio_priv(indio_dev);
+ data->regmap = devm_regmap_init_i2c(client, &max44000_regmap_config);
+ if (IS_ERR(data->regmap)) {
+ dev_err(&client->dev, "regmap_init failed!\n");
+ return PTR_ERR(data->regmap);
+ }
+
+ i2c_set_clientdata(client, indio_dev);
+ mutex_init(&data->lock);
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->info = &max44000_info;
+ indio_dev->name = MAX44000_DRV_NAME;
+ indio_dev->channels = max44000_channels;
+ indio_dev->num_channels = ARRAY_SIZE(max44000_channels);
+
+ /*
+ * The device doesn't have a reset function so we just clear some
+ * important bits at probe time to ensure sane operation.
+ *
+ * Since we don't support interrupts/events the threshold values are
+ * not important. We also don't touch trim values.
+ */
+
+ /* Reset ALS scaling bits */
+ ret = regmap_write(data->regmap, MAX44000_REG_CFG_RX,
+ MAX44000_REG_CFG_RX_DEFAULT);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to write default CFG_RX: %d\n",
+ ret);
+ return ret;
+ }
+
+ /*
+ * By default the LED pulse used for the proximity sensor is disabled.
+ * Set a middle value so that we get some sort of valid data by default.
+ */
+ ret = max44000_write_led_current_raw(data, MAX44000_LED_CURRENT_DEFAULT);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to write init config: %d\n", ret);
+ return ret;
+ }
+
+ /* Reset CFG bits to ALS_PRX mode which allows easy reading of both values. */
+ reg = MAX44000_CFG_TRIM | MAX44000_CFG_MODE_ALS_PRX;
+ ret = regmap_write(data->regmap, MAX44000_REG_CFG_MAIN, reg);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to write init config: %d\n", ret);
+ return ret;
+ }
+
+ /* Read status at least once to clear any stale interrupt bits. */
+ ret = regmap_read(data->regmap, MAX44000_REG_STATUS, ®);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to read init status: %d\n", ret);
+ return ret;
+ }
+
+ ret = iio_triggered_buffer_setup(indio_dev, NULL, max44000_trigger_handler, NULL);
+ if (ret < 0) {
+ dev_err(&client->dev, "iio triggered buffer setup failed\n");
+ return ret;
+ }
+
+ return iio_device_register(indio_dev);
+}
+
+static int max44000_remove(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+ iio_device_unregister(indio_dev);
+ iio_triggered_buffer_cleanup(indio_dev);
+
+ return 0;
+}
+
+static const struct i2c_device_id max44000_id[] = {
+ {"max44000", 0},
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, max44000_id);
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id max44000_acpi_match[] = {
+ {"MAX44000", 0},
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, max44000_acpi_match);
+#endif
+
+static struct i2c_driver max44000_driver = {
+ .driver = {
+ .name = MAX44000_DRV_NAME,
+ .acpi_match_table = ACPI_PTR(max44000_acpi_match),
+ },
+ .probe = max44000_probe,
+ .remove = max44000_remove,
+ .id_table = max44000_id,
+};
+
+module_i2c_driver(max44000_driver);
+
+MODULE_AUTHOR("Crestez Dan Leonard <leonard.crestez@intel.com>");
+MODULE_DESCRIPTION("MAX44000 Ambient and Infrared Proximity Sensor");
+MODULE_LICENSE("GPL v2");