[PATCH v6 0/2] Add support and documentation for UPISEMI us5182d als and proximity sensor

[PATCH v6 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 v6 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@intel.com>
---
 Changes since v5:
 * fixed typos (thank you, Peter)

 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..49dab3c
--- /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 thresholds 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 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");
-- 
1.9.1

Re: [PATCH v6 1/2] iio: light: Add support for UPISEMI uS5182d als and proximity sensor

[Jonathan Cameron]

On 20/08/15 11:12, Adriana Reus wrote:
> 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>
Applied to the togreg branch of iio.git - initially pushed out
as testing for the autobuilders to play with it.

Thanks,

Jonathan
> ---
>  Changes since v5:
>  * fixed typos (thank you, Peter)
> 
>  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..49dab3c
> --- /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 thresholds 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 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-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>");
> +MODULE_DESCRIPTION("Driver for us5182d Proximity and Light Sensor");
> +MODULE_LICENSE("GPL v2");
> 

[PATCH v6 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>
---
 .../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

Re: [PATCH v6 2/2] devicetree: Add documentation for UPISEMI us5182d ALS and Proximity sensor

[Jonathan Cameron]

On 20/08/15 11:12, Adriana Reus wrote:
> 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-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
This isn't that trivial so I'd like some device tree maintainer
input if possible.

For now I've backed out the driver from my tree (given timing we have
loads of time to sort this out!)

Anyhow, anyone device tree related able to take a look at this.

Adriana, btw these should be cc'd to the device tree maintainers in
the first place (now added).

Jonathan
> ---
>  .../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.
> 

Re: [PATCH v6 2/2] devicetree: Add documentation for UPISEMI us5182d ALS and Proximity sensor

[Rob Herring]

On Thu, Aug 27, 2015 at 3:23 PM, Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> wrote:
> On 20/08/15 11:12, Adriana Reus wrote:
>> 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-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> This isn't that trivial so I'd like some device tree maintainer
> input if possible.

It seems fairly reasonable to me. Would other ALS or proximity sensors
need similar properties?

> For now I've backed out the driver from my tree (given timing we have
> loads of time to sort this out!)
>
> Anyhow, anyone device tree related able to take a look at this.
>
> Adriana, btw these should be cc'd to the device tree maintainers in
> the first place (now added).
>
> Jonathan
>> ---
>>  .../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:

Do you expect certain defaults if not present? Some description of how
all these values are determined would be useful.


>> +- upisemi,glass-coef: glass attenuation factor
>> +- upisemi,dark-ths: array of thresholds (adc counts) corresponding to every scale

What is the size of the array and valid range of values?

Be specific this is 16-bit property.

>> +- 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

Be specific this is an 8-bit property.

>> +
>> +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.
>>
>

Re: [PATCH v6 2/2] devicetree: Add documentation for UPISEMI us5182d ALS and Proximity sensor

[Adriana Reus]

Thanks for your feedback, some comments inline.

On 31.08.2015 18:38, Rob Herring wrote:
> On Thu, Aug 27, 2015 at 3:23 PM, Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> wrote:
>> On 20/08/15 11:12, Adriana Reus wrote:
>>> 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-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
>> This isn't that trivial so I'd like some device tree maintainer
>> input if possible.
>
> It seems fairly reasonable to me. Would other ALS or proximity sensors
> need similar properties?
The "glass-coef" is intended to compensate for the material (glass) that 
may be covering the sensor if it's integrated in a phone, tablet etc. I 
chose 1000 as resolution for this scaling factor (i'll add a more 
detailed description). So possibly similar properties could be used for 
other als sensors as well.

The last 3 tuning parameters are specific to this particular sensor.
>
>> For now I've backed out the driver from my tree (given timing we have
>> loads of time to sort this out!)
>>
>> Anyhow, anyone device tree related able to take a look at this.
>>
>> Adriana, btw these should be cc'd to the device tree maintainers in
>> the first place (now added).
>>
>> Jonathan
>>> ---
>>>   .../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:
>
> Do you expect certain defaults if not present? Some description of how
> all these values are determined would be useful.
Yes, if not present they will fall back to default values - the values 
in the example.
- the glass-coef one is 1000 by default - so no glass compensation by 
default (lux = lux * 1000/1000)
- the others were determined experimentally - by fine tuning starting 
from the default values in those registers).
>
>
>>> +- upisemi,glass-coef: glass attenuation factor
>>> +- upisemi,dark-ths: array of thresholds (adc counts) corresponding to every scale
>
> What is the size of the array and valid range of values?
>
> Be specific this is 16-bit property.
Ok, I'll add this info in a following patch set.
>
>>> +- 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
>
> Be specific this is an 8-bit property.
ok
>
>>> +
>>> +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.
>>>
>>

Re: [PATCH v6 2/2] devicetree: Add documentation for UPISEMI us5182d ALS and Proximity sensor

[Rob Herring]

On 09/07/2015 08:59 AM, Adriana Reus wrote:
> Thanks for your feedback, some comments inline.
> 
> On 31.08.2015 18:38, Rob Herring wrote:
>> On Thu, Aug 27, 2015 at 3:23 PM, Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
>> wrote:
>>> On 20/08/15 11:12, Adriana Reus wrote:
>>>> 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-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
>>> This isn't that trivial so I'd like some device tree maintainer
>>> input if possible.
>>
>> It seems fairly reasonable to me. Would other ALS or proximity sensors
>> need similar properties?
> The "glass-coef" is intended to compensate for the material (glass) that
> may be covering the sensor if it's integrated in a phone, tablet etc. I
> chose 1000 as resolution for this scaling factor (i'll add a more
> detailed description). So possibly similar properties could be used for
> other als sensors as well.

Seems like amstaos,cover-comp-gain would be doing the same thing. But it
is defined as an integer, so I'm not sure how that would work.

> 
> The last 3 tuning parameters are specific to this particular sensor.
>>
>>> For now I've backed out the driver from my tree (given timing we have
>>> loads of time to sort this out!)
>>>
>>> Anyhow, anyone device tree related able to take a look at this.
>>>
>>> Adriana, btw these should be cc'd to the device tree maintainers in
>>> the first place (now added).
>>>
>>> Jonathan
>>>> ---
>>>>   .../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:
>>
>> Do you expect certain defaults if not present? Some description of how
>> all these values are determined would be useful.
> Yes, if not present they will fall back to default values - the values
> in the example.
> - the glass-coef one is 1000 by default - so no glass compensation by
> default (lux = lux * 1000/1000)
> - the others were determined experimentally - by fine tuning starting
> from the default values in those registers).

So the default if the properties are not present is a default register
value or a default in the driver?

Rob

Re: [PATCH v6 2/2] devicetree: Add documentation for UPISEMI us5182d ALS and Proximity sensor

[Adriana Reus]

Hi,

Sorry for my delayed response, answers inline.

Thank you,
Adriana
On 09.09.2015 04:05, Rob Herring wrote:
> On 09/07/2015 08:59 AM, Adriana Reus wrote:
>> Thanks for your feedback, some comments inline.
>>
>> On 31.08.2015 18:38, Rob Herring wrote:
>>> On Thu, Aug 27, 2015 at 3:23 PM, Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
>>> wrote:
>>>> On 20/08/15 11:12, Adriana Reus wrote:
>>>>> 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-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
>>>> This isn't that trivial so I'd like some device tree maintainer
>>>> input if possible.
>>>
>>> It seems fairly reasonable to me. Would other ALS or proximity sensors
>>> need similar properties?
>> The "glass-coef" is intended to compensate for the material (glass) that
>> may be covering the sensor if it's integrated in a phone, tablet etc. I
>> chose 1000 as resolution for this scaling factor (i'll add a more
>> detailed description). So possibly similar properties could be used for
>> other als sensors as well.
>
> Seems like amstaos,cover-comp-gain would be doing the same thing. But it
> is defined as an integer, so I'm not sure how that would work.
Indeed it seems similar. I had a quick look over it and from what I 
understand it seems to act like a straightforward scaling factor, only 
difference being that it's an int, I opted to float for a better tuning 
and resolution.
>
>>
>> The last 3 tuning parameters are specific to this particular sensor.
>>>
>>>> For now I've backed out the driver from my tree (given timing we have
>>>> loads of time to sort this out!)
>>>>
>>>> Anyhow, anyone device tree related able to take a look at this.
>>>>
>>>> Adriana, btw these should be cc'd to the device tree maintainers in
>>>> the first place (now added).
>>>>
>>>> Jonathan
>>>>> ---
>>>>>    .../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:
>>>
>>> Do you expect certain defaults if not present? Some description of how
>>> all these values are determined would be useful.
>> Yes, if not present they will fall back to default values - the values
>> in the example.
>> - the glass-coef one is 1000 by default - so no glass compensation by
>> default (lux = lux * 1000/1000)
>> - the others were determined experimentally - by fine tuning starting
>> from the default values in those registers).
>
> So the default if the properties are not present is a default register
> value or a default in the driver?

A default in the driver.
>
> Rob
>