[PATCH v5 0/2] Add support and documentation for UPISEMI us5182d als and proximity sensor

[PATCH v5 0/2] Add support and documentation for UPISEMI us5182d als and proximity sensor

[Adriana Reus]

This series adds basic support for this als and proximity sensor
and devicetree docs.

Adriana Reus (2):
  iio: light: Add support for UPISEMI uS5182d als and proximity sensor
  devicetree: Add documentation for UPISEMI us5182d ALS and Proximity
    sensor

 .../devicetree/bindings/iio/light/us5182d.txt      |  23 +
 .../devicetree/bindings/vendor-prefixes.txt        |   1 +
 drivers/iio/light/Kconfig                          |  10 +
 drivers/iio/light/Makefile                         |   1 +
 drivers/iio/light/us5182d.c                        | 507 +++++++++++++++++++++
 5 files changed, 542 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/light/us5182d.txt
 create mode 100644 drivers/iio/light/us5182d.c

-- 
1.9.1

[PATCH v5 1/2] iio: light: Add support for UPISEMI uS5182d als and proximity sensor

[Adriana Reus]

Add support for UPISEMI us5182d als and proximity sensor.
Supports raw readings.
Data sheet for this device can be found here:
http://www.upi-semi.com/temp/uS5182D-DS-P0103-temp.pdf

Signed-off-by: Adriana Reus <adriana.reus-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
---
 Changes since v4:
 * Added a comment explaining the opmode set/store behaviour.

 drivers/iio/light/Kconfig   |  10 +
 drivers/iio/light/Makefile  |   1 +
 drivers/iio/light/us5182d.c | 507 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 518 insertions(+)
 create mode 100644 drivers/iio/light/us5182d.c

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index 7ed859a..0442f01 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -287,6 +287,16 @@ config TSL4531
 	 To compile this driver as a module, choose M here: the
 	 module will be called tsl4531.
 
+config US5182D
+	tristate "UPISEMI light and proximity sensor"
+	depends on I2C
+	help
+	 If you say yes here you get support for the UPISEMI US5182D
+	 ambient light and proximity sensor.
+
+	 This driver can also be built as a module.  If so, the module
+	 will be called us5182d.
+
 config VCNL4000
 	tristate "VCNL4000 combined ALS and proximity sensor"
 	depends on I2C
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index 91c74c0..528cc8f 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -27,4 +27,5 @@ obj-$(CONFIG_STK3310)          += stk3310.o
 obj-$(CONFIG_TCS3414)		+= tcs3414.o
 obj-$(CONFIG_TCS3472)		+= tcs3472.o
 obj-$(CONFIG_TSL4531)		+= tsl4531.o
+obj-$(CONFIG_US5182D)		+= us5182d.o
 obj-$(CONFIG_VCNL4000)		+= vcnl4000.o
diff --git a/drivers/iio/light/us5182d.c b/drivers/iio/light/us5182d.c
new file mode 100644
index 0000000..7d356e6
--- /dev/null
+++ b/drivers/iio/light/us5182d.c
@@ -0,0 +1,507 @@
+/*
+ * Copyright (c) 2015 Intel Corporation
+ *
+ * Driver for UPISEMI us5182d Proximity and Ambient Light Sensor.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * To do: Interrupt support.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/mutex.h>
+
+#define US5182D_REG_CFG0				0x00
+#define US5182D_CFG0_ONESHOT_EN				BIT(6)
+#define US5182D_CFG0_SHUTDOWN_EN			BIT(7)
+#define US5182D_CFG0_WORD_ENABLE			BIT(0)
+
+#define US5182D_REG_CFG1				0x01
+#define US5182D_CFG1_ALS_RES16				BIT(4)
+#define US5182D_CFG1_AGAIN_DEFAULT			0x00
+
+#define US5182D_REG_CFG2				0x02
+#define US5182D_CFG2_PX_RES16				BIT(4)
+#define US5182D_CFG2_PXGAIN_DEFAULT			BIT(2)
+
+#define US5182D_REG_CFG3				0x03
+#define US5182D_CFG3_LED_CURRENT100			(BIT(4) | BIT(5))
+
+#define US5182D_REG_CFG4				0x10
+
+/*
+ * Registers for tuning the auto dark current cancelling feature.
+ * DARK_TH(reg 0x27,0x28) - threshold (counts) for auto dark cancelling.
+ * when ALS  > DARK_TH --> ALS_Code = ALS - Upper(0x2A) * Dark
+ * when ALS < DARK_TH --> ALS_Code = ALS - Lower(0x29) * Dark
+ */
+#define US5182D_REG_UDARK_TH			0x27
+#define US5182D_REG_DARK_AUTO_EN		0x2b
+#define US5182D_REG_AUTO_LDARK_GAIN		0x29
+#define US5182D_REG_AUTO_HDARK_GAIN		0x2a
+
+#define US5182D_OPMODE_ALS			0x01
+#define US5182D_OPMODE_PX			0x02
+#define US5182D_OPMODE_SHIFT			4
+
+#define US5182D_REG_DARK_AUTO_EN_DEFAULT	0x80
+#define US5182D_REG_AUTO_LDARK_GAIN_DEFAULT	0x16
+#define US5182D_REG_AUTO_HDARK_GAIN_DEFAULT	0x00
+
+#define US5182D_REG_ADL				0x0c
+#define US5182D_REG_PDL				0x0e
+
+#define US5182D_REG_MODE_STORE			0x21
+#define US5182D_STORE_MODE			0x01
+
+#define US5182D_REG_CHIPID			0xb2
+
+#define US5182D_OPMODE_MASK			GENMASK(5, 4)
+#define US5182D_AGAIN_MASK			0x07
+#define US5182D_RESET_CHIP			0x01
+
+#define US5182D_CHIPID				0x26
+#define US5182D_DRV_NAME			"us5182d"
+
+#define US5182D_GA_RESOLUTION			1000
+
+#define US5182D_READ_BYTE			1
+#define US5182D_READ_WORD			2
+#define US5182D_OPSTORE_SLEEP_TIME		20 /* ms */
+
+/* Available ranges: [12354, 7065, 3998, 2202, 1285, 498, 256, 138] lux */
+static const int us5182d_scales[] = {188500, 107800, 61000, 33600, 19600, 7600,
+				     3900, 2100};
+
+/*
+ * Experimental tresholds that work with US5182D sensor on evaluation board
+ * roughly between 12-32 lux
+ */
+static u16 us5182d_dark_ths_vals[] = {170, 200, 512, 512, 800, 2000, 4000,
+				      8000};
+
+enum mode {
+	US5182D_ALS_PX,
+	US5182D_ALS_ONLY,
+	US5182D_PX_ONLY
+};
+
+struct us5182d_data {
+	struct i2c_client *client;
+	struct mutex lock;
+
+	/* Glass attenuation factor */
+	u32 ga;
+
+	/* Dark gain tuning */
+	u8 lower_dark_gain;
+	u8 upper_dark_gain;
+	u16 *us5182d_dark_ths;
+
+	u8 opmode;
+};
+
+static IIO_CONST_ATTR(in_illuminance_scale_available,
+		      "0.0021 0.0039 0.0076 0.0196 0.0336 0.061 0.1078 0.1885");
+
+static struct attribute *us5182d_attrs[] = {
+	&iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group us5182d_attr_group = {
+	.attrs = us5182d_attrs,
+};
+
+static const struct {
+	u8 reg;
+	u8 val;
+} us5182d_regvals[] = {
+	{US5182D_REG_CFG0, (US5182D_CFG0_SHUTDOWN_EN |
+			    US5182D_CFG0_WORD_ENABLE)},
+	{US5182D_REG_CFG1, US5182D_CFG1_ALS_RES16},
+	{US5182D_REG_CFG2, (US5182D_CFG2_PX_RES16 |
+			    US5182D_CFG2_PXGAIN_DEFAULT)},
+	{US5182D_REG_CFG3, US5182D_CFG3_LED_CURRENT100},
+	{US5182D_REG_MODE_STORE, US5182D_STORE_MODE},
+	{US5182D_REG_CFG4, 0x00},
+};
+
+static const struct iio_chan_spec us5182d_channels[] = {
+	{
+		.type = IIO_LIGHT,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+	},
+	{
+		.type = IIO_PROXIMITY,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+	}
+};
+
+static int us5182d_get_als(struct us5182d_data *data)
+{
+	int ret;
+	unsigned long result;
+
+	ret = i2c_smbus_read_word_data(data->client,
+				       US5182D_REG_ADL);
+	if (ret < 0)
+		return ret;
+
+	result = ret * data->ga / US5182D_GA_RESOLUTION;
+	if (result > 0xffff)
+		result = 0xffff;
+
+	return result;
+}
+
+static int us5182d_set_opmode(struct us5182d_data *data, u8 mode)
+{
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG0);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * In oneshot mode the chip will power itself down after taking the
+	 * required measurement.
+	 */
+	ret = ret | US5182D_CFG0_ONESHOT_EN;
+
+	/* update mode */
+	ret = ret & ~US5182D_OPMODE_MASK;
+	ret = ret | (mode << US5182D_OPMODE_SHIFT);
+
+	/*
+	 * After updating the operating mode, the chip requires that
+	 * the operation is stored, by writing 1 in the STORE_MODE
+	 * register (auto-clearing).
+	 */
+	ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG0, ret);
+	if (ret < 0)
+		return ret;
+
+	if (mode == data->opmode)
+		return 0;
+
+	ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_MODE_STORE,
+					US5182D_STORE_MODE);
+	if (ret < 0)
+		return ret;
+
+	data->opmode = mode;
+	msleep(US5182D_OPSTORE_SLEEP_TIME);
+
+	return 0;
+}
+
+static int us5182d_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan, int *val,
+			    int *val2, long mask)
+{
+	struct us5182d_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		switch (chan->type) {
+		case IIO_LIGHT:
+			mutex_lock(&data->lock);
+			ret = us5182d_set_opmode(data, US5182D_OPMODE_ALS);
+			if (ret < 0)
+				goto out_err;
+
+			ret = us5182d_get_als(data);
+			if (ret < 0)
+				goto out_err;
+			mutex_unlock(&data->lock);
+			*val = ret;
+			return IIO_VAL_INT;
+		case IIO_PROXIMITY:
+			mutex_lock(&data->lock);
+			ret = us5182d_set_opmode(data, US5182D_OPMODE_PX);
+			if (ret < 0)
+				goto out_err;
+
+			ret = i2c_smbus_read_word_data(data->client,
+						       US5182D_REG_PDL);
+			if (ret < 0)
+				goto out_err;
+			mutex_unlock(&data->lock);
+			*val = ret;
+			return  IIO_VAL_INT;
+		default:
+			return -EINVAL;
+		}
+
+	case IIO_CHAN_INFO_SCALE:
+		ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG1);
+		if (ret < 0)
+			return ret;
+
+		*val = 0;
+		*val2 = us5182d_scales[ret & US5182D_AGAIN_MASK];
+
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		return -EINVAL;
+	}
+
+	return -EINVAL;
+out_err:
+	mutex_unlock(&data->lock);
+	return ret;
+}
+
+/**`
+ * us5182d_update_dark_th - update Darh_Th registers
+ * @data	us5182d_data structure
+ * @index	index in us5182d_dark_ths array to use for the updated value
+ *
+ * Function needs to be called with a lock held because it needs two i2c write
+ * byte operations as these registers (0x27 0x28) don't work in word mode
+ * accessing.
+ */
+static int us5182d_update_dark_th(struct us5182d_data *data, int index)
+{
+	__be16 dark_th = cpu_to_be16(data->us5182d_dark_ths[index]);
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_UDARK_TH,
+					((u8 *)&dark_th)[0]);
+	if (ret < 0)
+		return ret;
+
+	return i2c_smbus_write_byte_data(data->client, US5182D_REG_UDARK_TH + 1,
+					((u8 *)&dark_th)[1]);
+}
+
+/**`
+ * us5182d_apply_scale - update the ALS scale
+ * @data	us5182d_data structure
+ * @index	index in us5182d_scales array to use for the updated value
+ *
+ * Function needs to be called with a lock held as we're having more than one
+ * i2c operations.
+ */
+static int us5182d_apply_scale(struct us5182d_data *data, int index)
+{
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG1);
+	if (ret < 0)
+		return ret;
+
+	ret = ret & (~US5182D_AGAIN_MASK);
+	ret |= index;
+
+	ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG1, ret);
+	if (ret < 0)
+		return ret;
+
+	return us5182d_update_dark_th(data, index);
+}
+
+static int us5182d_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan, int val,
+			     int val2, long mask)
+{
+	struct us5182d_data *data = iio_priv(indio_dev);
+	int ret, i;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		if (val != 0)
+			return -EINVAL;
+		for (i = 0; i < ARRAY_SIZE(us5182d_scales); i++)
+			if (val2 == us5182d_scales[i]) {
+				mutex_lock(&data->lock);
+				ret = us5182d_apply_scale(data, i);
+				mutex_unlock(&data->lock);
+				return ret;
+			}
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info us5182d_info = {
+	.driver_module	= THIS_MODULE,
+	.read_raw = us5182d_read_raw,
+	.write_raw = us5182d_write_raw,
+	.attrs = &us5182d_attr_group,
+};
+
+static int us5182d_reset(struct iio_dev *indio_dev)
+{
+	struct us5182d_data *data = iio_priv(indio_dev);
+
+	return i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG3,
+					 US5182D_RESET_CHIP);
+}
+
+static int us5182d_init(struct iio_dev *indio_dev)
+{
+	struct us5182d_data *data = iio_priv(indio_dev);
+	int i, ret;
+
+	ret = us5182d_reset(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	data->opmode = 0;
+	for (i = 0; i < ARRAY_SIZE(us5182d_regvals); i++) {
+		ret = i2c_smbus_write_byte_data(data->client,
+						us5182d_regvals[i].reg,
+						us5182d_regvals[i].val);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+static void us5182d_get_platform_data(struct iio_dev *indio_dev)
+{
+	struct us5182d_data *data = iio_priv(indio_dev);
+
+	if (device_property_read_u32(&data->client->dev, "upisemi,glass-coef",
+				     &data->ga))
+		data->ga = US5182D_GA_RESOLUTION;
+	if (device_property_read_u16_array(&data->client->dev,
+					   "upisemi,dark-ths",
+					   data->us5182d_dark_ths,
+					   ARRAY_SIZE(us5182d_dark_ths_vals)))
+		data->us5182d_dark_ths = us5182d_dark_ths_vals;
+	if (device_property_read_u8(&data->client->dev,
+				    "upisemi,upper-dark-gain",
+				    &data->upper_dark_gain))
+		data->upper_dark_gain = US5182D_REG_AUTO_HDARK_GAIN_DEFAULT;
+	if (device_property_read_u8(&data->client->dev,
+				    "upisemi,lower-dark-gain",
+				    &data->lower_dark_gain))
+		data->lower_dark_gain = US5182D_REG_AUTO_LDARK_GAIN_DEFAULT;
+}
+
+static int  us5182d_dark_gain_config(struct iio_dev *indio_dev)
+{
+	struct us5182d_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = us5182d_update_dark_th(data, US5182D_CFG1_AGAIN_DEFAULT);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_smbus_write_byte_data(data->client,
+					US5182D_REG_AUTO_LDARK_GAIN,
+					data->lower_dark_gain);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_smbus_write_byte_data(data->client,
+					US5182D_REG_AUTO_HDARK_GAIN,
+					data->upper_dark_gain);
+	if (ret < 0)
+		return ret;
+
+	return i2c_smbus_write_byte_data(data->client, US5182D_REG_DARK_AUTO_EN,
+					 US5182D_REG_DARK_AUTO_EN_DEFAULT);
+}
+
+static int us5182d_probe(struct i2c_client *client,
+			 const struct i2c_device_id *id)
+{
+	struct us5182d_data *data;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	data->client = client;
+
+	mutex_init(&data->lock);
+
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &us5182d_info;
+	indio_dev->name = US5182D_DRV_NAME;
+	indio_dev->channels = us5182d_channels;
+	indio_dev->num_channels = ARRAY_SIZE(us5182d_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CHIPID);
+	if (ret != US5182D_CHIPID) {
+		dev_err(&data->client->dev,
+			"Failed to detect US5182 light chip\n");
+		return (ret < 0) ? ret : -ENODEV;
+	}
+
+	us5182d_get_platform_data(indio_dev);
+	ret = us5182d_init(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	ret = us5182d_dark_gain_config(indio_dev);
+	if (ret < 0)
+		return ret;
+
+	return iio_device_register(indio_dev);
+}
+
+static int us5182d_remove(struct i2c_client *client)
+{
+	iio_device_unregister(i2c_get_clientdata(client));
+	return i2c_smbus_write_byte_data(client, US5182D_REG_CFG0,
+					 US5182D_CFG0_SHUTDOWN_EN);
+}
+
+static const struct acpi_device_id us5182d_acpi_match[] = {
+	{ "USD5182", 0},
+	{}
+};
+
+MODULE_DEVICE_TABLE(acpi, us5182d_acpi_match);
+
+static const struct i2c_device_id us5182d_id[] = {
+		{"usd5182", 0},
+		{}
+};
+
+MODULE_DEVICE_TABLE(i2c, us5182d_id);
+
+static struct i2c_driver us5182d_driver = {
+	.driver = {
+		.name = US5182D_DRV_NAME,
+		.acpi_match_table = ACPI_PTR(us5182d_acpi_match),
+	},
+	.probe = us5182d_probe,
+	.remove = us5182d_remove,
+	.id_table = us5182d_id,
+
+};
+module_i2c_driver(us5182d_driver);
+
+MODULE_AUTHOR("Adriana Reus <adriana.reus-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>");
+MODULE_DESCRIPTION("Driver for us5182d Proximity and Light Sensor");
+MODULE_LICENSE("GPL v2");
-- 
1.9.1

Re: [PATCH v5 1/2] iio: light: Add support for UPISEMI uS5182d als and proximity sensor

[Peter Meerwald]

> Add support for UPISEMI us5182d als and proximity sensor.
> Supports raw readings.
> Data sheet for this device can be found here:
> http://www.upi-semi.com/temp/uS5182D-DS-P0103-temp.pdf

nitpicking below
 
> Signed-off-by: Adriana Reus <adriana.reus@intel.com>
> ---
>  Changes since v4:
>  * Added a comment explaining the opmode set/store behaviour.
> 
>  drivers/iio/light/Kconfig   |  10 +
>  drivers/iio/light/Makefile  |   1 +
>  drivers/iio/light/us5182d.c | 507 ++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 518 insertions(+)
>  create mode 100644 drivers/iio/light/us5182d.c
> 
> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
> index 7ed859a..0442f01 100644
> --- a/drivers/iio/light/Kconfig
> +++ b/drivers/iio/light/Kconfig
> @@ -287,6 +287,16 @@ config TSL4531
>  	 To compile this driver as a module, choose M here: the
>  	 module will be called tsl4531.
>  
> +config US5182D
> +	tristate "UPISEMI light and proximity sensor"
> +	depends on I2C
> +	help
> +	 If you say yes here you get support for the UPISEMI US5182D
> +	 ambient light and proximity sensor.
> +
> +	 This driver can also be built as a module.  If so, the module
> +	 will be called us5182d.
> +
>  config VCNL4000
>  	tristate "VCNL4000 combined ALS and proximity sensor"
>  	depends on I2C
> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
> index 91c74c0..528cc8f 100644
> --- a/drivers/iio/light/Makefile
> +++ b/drivers/iio/light/Makefile
> @@ -27,4 +27,5 @@ obj-$(CONFIG_STK3310)          += stk3310.o
>  obj-$(CONFIG_TCS3414)		+= tcs3414.o
>  obj-$(CONFIG_TCS3472)		+= tcs3472.o
>  obj-$(CONFIG_TSL4531)		+= tsl4531.o
> +obj-$(CONFIG_US5182D)		+= us5182d.o
>  obj-$(CONFIG_VCNL4000)		+= vcnl4000.o
> diff --git a/drivers/iio/light/us5182d.c b/drivers/iio/light/us5182d.c
> new file mode 100644
> index 0000000..7d356e6
> --- /dev/null
> +++ b/drivers/iio/light/us5182d.c
> @@ -0,0 +1,507 @@
> +/*
> + * Copyright (c) 2015 Intel Corporation
> + *
> + * Driver for UPISEMI us5182d Proximity and Ambient Light Sensor.
> + *
> + * 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.
> + *
> + * This program is distributed in the hope it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> + * more details.
> + *
> + * To do: Interrupt support.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/acpi.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/mutex.h>
> +
> +#define US5182D_REG_CFG0				0x00
> +#define US5182D_CFG0_ONESHOT_EN				BIT(6)
> +#define US5182D_CFG0_SHUTDOWN_EN			BIT(7)
> +#define US5182D_CFG0_WORD_ENABLE			BIT(0)
> +
> +#define US5182D_REG_CFG1				0x01
> +#define US5182D_CFG1_ALS_RES16				BIT(4)
> +#define US5182D_CFG1_AGAIN_DEFAULT			0x00
> +
> +#define US5182D_REG_CFG2				0x02
> +#define US5182D_CFG2_PX_RES16				BIT(4)
> +#define US5182D_CFG2_PXGAIN_DEFAULT			BIT(2)
> +
> +#define US5182D_REG_CFG3				0x03
> +#define US5182D_CFG3_LED_CURRENT100			(BIT(4) | BIT(5))
> +
> +#define US5182D_REG_CFG4				0x10
> +
> +/*
> + * Registers for tuning the auto dark current cancelling feature.
> + * DARK_TH(reg 0x27,0x28) - threshold (counts) for auto dark cancelling.
> + * when ALS  > DARK_TH --> ALS_Code = ALS - Upper(0x2A) * Dark
> + * when ALS < DARK_TH --> ALS_Code = ALS - Lower(0x29) * Dark
> + */
> +#define US5182D_REG_UDARK_TH			0x27
> +#define US5182D_REG_DARK_AUTO_EN		0x2b
> +#define US5182D_REG_AUTO_LDARK_GAIN		0x29
> +#define US5182D_REG_AUTO_HDARK_GAIN		0x2a
> +
> +#define US5182D_OPMODE_ALS			0x01
> +#define US5182D_OPMODE_PX			0x02
> +#define US5182D_OPMODE_SHIFT			4
> +
> +#define US5182D_REG_DARK_AUTO_EN_DEFAULT	0x80
> +#define US5182D_REG_AUTO_LDARK_GAIN_DEFAULT	0x16
> +#define US5182D_REG_AUTO_HDARK_GAIN_DEFAULT	0x00
> +
> +#define US5182D_REG_ADL				0x0c
> +#define US5182D_REG_PDL				0x0e
> +
> +#define US5182D_REG_MODE_STORE			0x21
> +#define US5182D_STORE_MODE			0x01
> +
> +#define US5182D_REG_CHIPID			0xb2
> +
> +#define US5182D_OPMODE_MASK			GENMASK(5, 4)
> +#define US5182D_AGAIN_MASK			0x07
> +#define US5182D_RESET_CHIP			0x01
> +
> +#define US5182D_CHIPID				0x26
> +#define US5182D_DRV_NAME			"us5182d"
> +
> +#define US5182D_GA_RESOLUTION			1000
> +
> +#define US5182D_READ_BYTE			1
> +#define US5182D_READ_WORD			2
> +#define US5182D_OPSTORE_SLEEP_TIME		20 /* ms */
> +
> +/* Available ranges: [12354, 7065, 3998, 2202, 1285, 498, 256, 138] lux */
> +static const int us5182d_scales[] = {188500, 107800, 61000, 33600, 19600, 7600,
> +				     3900, 2100};
> +
> +/*
> + * Experimental tresholds that work with US5182D sensor on evaluation board

threshold

> + * roughly between 12-32 lux
> + */
> +static u16 us5182d_dark_ths_vals[] = {170, 200, 512, 512, 800, 2000, 4000,
> +				      8000};
> +
> +enum mode {
> +	US5182D_ALS_PX,
> +	US5182D_ALS_ONLY,
> +	US5182D_PX_ONLY
> +};
> +
> +struct us5182d_data {
> +	struct i2c_client *client;
> +	struct mutex lock;
> +
> +	/* Glass attenuation factor */
> +	u32 ga;
> +
> +	/* Dark gain tuning */
> +	u8 lower_dark_gain;
> +	u8 upper_dark_gain;
> +	u16 *us5182d_dark_ths;
> +
> +	u8 opmode;
> +};
> +
> +static IIO_CONST_ATTR(in_illuminance_scale_available,
> +		      "0.0021 0.0039 0.0076 0.0196 0.0336 0.061 0.1078 0.1885");
> +
> +static struct attribute *us5182d_attrs[] = {
> +	&iio_const_attr_in_illuminance_scale_available.dev_attr.attr,
> +	NULL
> +};
> +
> +static const struct attribute_group us5182d_attr_group = {
> +	.attrs = us5182d_attrs,
> +};
> +
> +static const struct {
> +	u8 reg;
> +	u8 val;
> +} us5182d_regvals[] = {
> +	{US5182D_REG_CFG0, (US5182D_CFG0_SHUTDOWN_EN |
> +			    US5182D_CFG0_WORD_ENABLE)},
> +	{US5182D_REG_CFG1, US5182D_CFG1_ALS_RES16},
> +	{US5182D_REG_CFG2, (US5182D_CFG2_PX_RES16 |
> +			    US5182D_CFG2_PXGAIN_DEFAULT)},
> +	{US5182D_REG_CFG3, US5182D_CFG3_LED_CURRENT100},
> +	{US5182D_REG_MODE_STORE, US5182D_STORE_MODE},
> +	{US5182D_REG_CFG4, 0x00},
> +};
> +
> +static const struct iio_chan_spec us5182d_channels[] = {
> +	{
> +		.type = IIO_LIGHT,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE),
> +	},
> +	{
> +		.type = IIO_PROXIMITY,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +	}
> +};
> +
> +static int us5182d_get_als(struct us5182d_data *data)
> +{
> +	int ret;
> +	unsigned long result;
> +
> +	ret = i2c_smbus_read_word_data(data->client,
> +				       US5182D_REG_ADL);
> +	if (ret < 0)
> +		return ret;
> +
> +	result = ret * data->ga / US5182D_GA_RESOLUTION;
> +	if (result > 0xffff)
> +		result = 0xffff;
> +
> +	return result;
> +}
> +
> +static int us5182d_set_opmode(struct us5182d_data *data, u8 mode)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG0);
> +	if (ret < 0)
> +		return ret;
> +
> +	/*
> +	 * In oneshot mode the chip will power itself down after taking the
> +	 * required measurement.
> +	 */
> +	ret = ret | US5182D_CFG0_ONESHOT_EN;
> +
> +	/* update mode */
> +	ret = ret & ~US5182D_OPMODE_MASK;
> +	ret = ret | (mode << US5182D_OPMODE_SHIFT);
> +
> +	/*
> +	 * After updating the operating mode, the chip requires that
> +	 * the operation is stored, by writing 1 in the STORE_MODE
> +	 * register (auto-clearing).
> +	 */
> +	ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG0, ret);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (mode == data->opmode)
> +		return 0;
> +
> +	ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_MODE_STORE,
> +					US5182D_STORE_MODE);
> +	if (ret < 0)
> +		return ret;
> +
> +	data->opmode = mode;
> +	msleep(US5182D_OPSTORE_SLEEP_TIME);
> +
> +	return 0;
> +}
> +
> +static int us5182d_read_raw(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan, int *val,
> +			    int *val2, long mask)
> +{
> +	struct us5182d_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		switch (chan->type) {
> +		case IIO_LIGHT:
> +			mutex_lock(&data->lock);
> +			ret = us5182d_set_opmode(data, US5182D_OPMODE_ALS);
> +			if (ret < 0)
> +				goto out_err;
> +
> +			ret = us5182d_get_als(data);
> +			if (ret < 0)
> +				goto out_err;
> +			mutex_unlock(&data->lock);
> +			*val = ret;
> +			return IIO_VAL_INT;
> +		case IIO_PROXIMITY:
> +			mutex_lock(&data->lock);
> +			ret = us5182d_set_opmode(data, US5182D_OPMODE_PX);
> +			if (ret < 0)
> +				goto out_err;
> +
> +			ret = i2c_smbus_read_word_data(data->client,
> +						       US5182D_REG_PDL);
> +			if (ret < 0)
> +				goto out_err;
> +			mutex_unlock(&data->lock);
> +			*val = ret;
> +			return  IIO_VAL_INT;
> +		default:
> +			return -EINVAL;
> +		}
> +
> +	case IIO_CHAN_INFO_SCALE:
> +		ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG1);
> +		if (ret < 0)
> +			return ret;
> +
> +		*val = 0;
> +		*val2 = us5182d_scales[ret & US5182D_AGAIN_MASK];
> +
> +		return IIO_VAL_INT_PLUS_MICRO;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return -EINVAL;
> +out_err:
> +	mutex_unlock(&data->lock);
> +	return ret;
> +}
> +
> +/**`

there is an extra character (`) to remove

> + * us5182d_update_dark_th - update Darh_Th registers
> + * @data	us5182d_data structure
> + * @index	index in us5182d_dark_ths array to use for the updated value
> + *
> + * Function needs to be called with a lock held because it needs two i2c write
> + * byte operations as these registers (0x27 0x28) don't work in word mode
> + * accessing.
> + */
> +static int us5182d_update_dark_th(struct us5182d_data *data, int index)
> +{
> +	__be16 dark_th = cpu_to_be16(data->us5182d_dark_ths[index]);
> +	int ret;
> +
> +	ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_UDARK_TH,
> +					((u8 *)&dark_th)[0]);
> +	if (ret < 0)
> +		return ret;
> +
> +	return i2c_smbus_write_byte_data(data->client, US5182D_REG_UDARK_TH + 1,
> +					((u8 *)&dark_th)[1]);
> +}
> +
> +/**`
> + * us5182d_apply_scale - update the ALS scale
> + * @data	us5182d_data structure
> + * @index	index in us5182d_scales array to use for the updated value
> + *
> + * Function needs to be called with a lock held as we're having more than one
> + * i2c operations.

operation

> + */
> +static int us5182d_apply_scale(struct us5182d_data *data, int index)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CFG1);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = ret & (~US5182D_AGAIN_MASK);
> +	ret |= index;
> +
> +	ret = i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG1, ret);
> +	if (ret < 0)
> +		return ret;
> +
> +	return us5182d_update_dark_th(data, index);
> +}
> +
> +static int us5182d_write_raw(struct iio_dev *indio_dev,
> +			     struct iio_chan_spec const *chan, int val,
> +			     int val2, long mask)
> +{
> +	struct us5182d_data *data = iio_priv(indio_dev);
> +	int ret, i;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_SCALE:
> +		if (val != 0)
> +			return -EINVAL;
> +		for (i = 0; i < ARRAY_SIZE(us5182d_scales); i++)
> +			if (val2 == us5182d_scales[i]) {
> +				mutex_lock(&data->lock);
> +				ret = us5182d_apply_scale(data, i);
> +				mutex_unlock(&data->lock);
> +				return ret;
> +			}
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static const struct iio_info us5182d_info = {
> +	.driver_module	= THIS_MODULE,
> +	.read_raw = us5182d_read_raw,
> +	.write_raw = us5182d_write_raw,
> +	.attrs = &us5182d_attr_group,
> +};
> +
> +static int us5182d_reset(struct iio_dev *indio_dev)
> +{
> +	struct us5182d_data *data = iio_priv(indio_dev);
> +
> +	return i2c_smbus_write_byte_data(data->client, US5182D_REG_CFG3,
> +					 US5182D_RESET_CHIP);
> +}
> +
> +static int us5182d_init(struct iio_dev *indio_dev)
> +{
> +	struct us5182d_data *data = iio_priv(indio_dev);
> +	int i, ret;
> +
> +	ret = us5182d_reset(indio_dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	data->opmode = 0;
> +	for (i = 0; i < ARRAY_SIZE(us5182d_regvals); i++) {
> +		ret = i2c_smbus_write_byte_data(data->client,
> +						us5182d_regvals[i].reg,
> +						us5182d_regvals[i].val);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void us5182d_get_platform_data(struct iio_dev *indio_dev)
> +{
> +	struct us5182d_data *data = iio_priv(indio_dev);
> +
> +	if (device_property_read_u32(&data->client->dev, "upisemi,glass-coef",
> +				     &data->ga))
> +		data->ga = US5182D_GA_RESOLUTION;
> +	if (device_property_read_u16_array(&data->client->dev,
> +					   "upisemi,dark-ths",
> +					   data->us5182d_dark_ths,
> +					   ARRAY_SIZE(us5182d_dark_ths_vals)))
> +		data->us5182d_dark_ths = us5182d_dark_ths_vals;
> +	if (device_property_read_u8(&data->client->dev,
> +				    "upisemi,upper-dark-gain",
> +				    &data->upper_dark_gain))
> +		data->upper_dark_gain = US5182D_REG_AUTO_HDARK_GAIN_DEFAULT;
> +	if (device_property_read_u8(&data->client->dev,
> +				    "upisemi,lower-dark-gain",
> +				    &data->lower_dark_gain))
> +		data->lower_dark_gain = US5182D_REG_AUTO_LDARK_GAIN_DEFAULT;
> +}
> +
> +static int  us5182d_dark_gain_config(struct iio_dev *indio_dev)
> +{
> +	struct us5182d_data *data = iio_priv(indio_dev);
> +	int ret;
> +
> +	ret = us5182d_update_dark_th(data, US5182D_CFG1_AGAIN_DEFAULT);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = i2c_smbus_write_byte_data(data->client,
> +					US5182D_REG_AUTO_LDARK_GAIN,
> +					data->lower_dark_gain);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = i2c_smbus_write_byte_data(data->client,
> +					US5182D_REG_AUTO_HDARK_GAIN,
> +					data->upper_dark_gain);
> +	if (ret < 0)
> +		return ret;
> +
> +	return i2c_smbus_write_byte_data(data->client, US5182D_REG_DARK_AUTO_EN,
> +					 US5182D_REG_DARK_AUTO_EN_DEFAULT);
> +}
> +
> +static int us5182d_probe(struct i2c_client *client,
> +			 const struct i2c_device_id *id)
> +{
> +	struct us5182d_data *data;
> +	struct iio_dev *indio_dev;
> +	int ret;
> +
> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	data = iio_priv(indio_dev);
> +	i2c_set_clientdata(client, indio_dev);
> +	data->client = client;
> +
> +	mutex_init(&data->lock);
> +
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->info = &us5182d_info;
> +	indio_dev->name = US5182D_DRV_NAME;
> +	indio_dev->channels = us5182d_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(us5182d_channels);
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	ret = i2c_smbus_read_byte_data(data->client, US5182D_REG_CHIPID);
> +	if (ret != US5182D_CHIPID) {
> +		dev_err(&data->client->dev,
> +			"Failed to detect US5182 light chip\n");
> +		return (ret < 0) ? ret : -ENODEV;
> +	}
> +
> +	us5182d_get_platform_data(indio_dev);
> +	ret = us5182d_init(indio_dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = us5182d_dark_gain_config(indio_dev);
> +	if (ret < 0)
> +		return ret;
> +
> +	return iio_device_register(indio_dev);
> +}
> +
> +static int us5182d_remove(struct i2c_client *client)
> +{
> +	iio_device_unregister(i2c_get_clientdata(client));
> +	return i2c_smbus_write_byte_data(client, US5182D_REG_CFG0,
> +					 US5182D_CFG0_SHUTDOWN_EN);
> +}
> +
> +static const struct acpi_device_id us5182d_acpi_match[] = {
> +	{ "USD5182", 0},
> +	{}
> +};
> +
> +MODULE_DEVICE_TABLE(acpi, us5182d_acpi_match);
> +
> +static const struct i2c_device_id us5182d_id[] = {
> +		{"usd5182", 0},
> +		{}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, us5182d_id);
> +
> +static struct i2c_driver us5182d_driver = {
> +	.driver = {
> +		.name = US5182D_DRV_NAME,
> +		.acpi_match_table = ACPI_PTR(us5182d_acpi_match),
> +	},
> +	.probe = us5182d_probe,
> +	.remove = us5182d_remove,
> +	.id_table = us5182d_id,
> +
> +};
> +module_i2c_driver(us5182d_driver);
> +
> +MODULE_AUTHOR("Adriana Reus <adriana.reus@intel.com>");
> +MODULE_DESCRIPTION("Driver for us5182d Proximity and Light Sensor");
> +MODULE_LICENSE("GPL v2");
> 

-- 

Peter Meerwald
+43-664-2444418 (mobile)

[PATCH v5 2/2] devicetree: Add documentation for UPISEMI us5182d ALS and Proximity sensor

[Adriana Reus]

Added entries in i2c/vendor-prefixes for the us5182d als and proximity sensor.
Also added a documentation file for this sensor's properties.

Signed-off-by: Adriana Reus <adriana.reus@intel.com>
---
 No changes since v4 for the docs.

 .../devicetree/bindings/iio/light/us5182d.txt      | 23 ++++++++++++++++++++++
 .../devicetree/bindings/vendor-prefixes.txt        |  1 +
 2 files changed, 24 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/light/us5182d.txt

diff --git a/Documentation/devicetree/bindings/iio/light/us5182d.txt b/Documentation/devicetree/bindings/iio/light/us5182d.txt
new file mode 100644
index 0000000..7785c56
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/light/us5182d.txt
@@ -0,0 +1,23 @@
+* UPISEMI us5182d I2C ALS and Proximity sensor
+
+Required properties:
+- compatible: must be "upisemi,usd5182"
+- reg: the I2C address of the device
+
+Optional properties:
+- upisemi,glass-coef: glass attenuation factor
+- upisemi,dark-ths: array of thresholds (adc counts) corresponding to every scale
+- upisemi,upper-dark-gain: tuning factor(4 int and 4 fractional bits - Q4.4) applied when light > threshold
+- upisemi,lower-dark-gain: tuning factor(4 int and 4 fractional bits - Q4.4) applied when light < threshold
+
+Example:
+
+    usd5182@39 {
+                compatible = "upisemi,usd5182";
+                reg = <0x39>;
+                upisemi,glass-coef = < 1000 >;
+                upisemi,dark-ths = /bits/ 16 <170 200 512 512 800 2000 4000 8000>;
+                upisemi,upper-dark-gain = /bits/ 8 <0x00>;
+                upisemi,lower-dark-gain = /bits/ 8 <0x16>;
+    };
+
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index d444757..5b40bab 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -211,6 +211,7 @@ toshiba	Toshiba Corporation
 toumaz	Toumaz
 tplink	TP-LINK Technologies Co., Ltd.
 truly	Truly Semiconductors Limited
+upisemi	uPI Semiconductor Corp.
 usi	Universal Scientific Industrial Co., Ltd.
 v3	V3 Semiconductor
 variscite	Variscite Ltd.
-- 
1.9.1