Re: [PATCH v7 1/1] iio: jsa1212: Add JSA1212 proximity/ALS sensor

[sathyanarayanan kuppuswamy <sathyanarayanan.kuppuswamy@linux.intel.com>]

Hi Hartmut,

On 09/17/2014 01:48 PM, Hartmut Knaack wrote:
> Kuppuswamy Sathyanarayanan schrieb, Am 16.09.2014 05:54:
>> This patch adds a new driver for solteam opto JSA1212 proximity and
>> ambient light sensor.
>>
>> Basic details of the chip can be found here.
>>
>> http://www.solteamopto.com.tw/detail.php?ms=3&po_unit=2&pt_unit=29&p_unit=120
> Hi,
> after your explanation of the power states, I now wonder, why you would need to power-down the device in jsa1212_suspend() and check, which parts need to be powered-up in jsa1212_resume(). The way I understand it, you only access the device to read data, after initialization. Therefor you power up the device, wait, read data and power down. All secured by a mutex. So, as long as no data is read, the device will always remain in low-power state.
Yes, What you mentioned is true for current use case. But once we 
implement interrupt & IIO event support, We will have scenarios where 
the device is on when suspend is triggered. I have just added the power 
management code with that scenario in mind.
>> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
>> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
>> ---
>>   drivers/iio/light/Kconfig   |  10 +
>>   drivers/iio/light/Makefile  |   1 +
>>   drivers/iio/light/jsa1212.c | 471 ++++++++++++++++++++++++++++++++++++++++++++
>>   3 files changed, 482 insertions(+)
>>   create mode 100644 drivers/iio/light/jsa1212.c
>>
>> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
>> index bf05ca5..b81d8a3 100644
>> --- a/drivers/iio/light/Kconfig
>> +++ b/drivers/iio/light/Kconfig
>> @@ -99,6 +99,16 @@ config HID_SENSOR_PROX
>>   	  To compile this driver as a module, choose M here: the
>>   	  module will be called hid-sensor-prox.
>>   
>> +config JSA1212
>> +	tristate "JSA1212 ALS and proximity sensor driver"
>> +	depends on I2C
>> +	help
>> +	 Say Y here if you want to build a IIO driver for JSA1212
>> +	 proximity & ALS sensor device.
>> +
>> +	 To compile this driver as a module, choose M here:
>> +	 the module will be called jsa1212.
>> +
>>   config SENSORS_LM3533
>>   	tristate "LM3533 ambient light sensor"
>>   	depends on MFD_LM3533
>> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
>> index 8b8c09f..23c6aa9 100644
>> --- a/drivers/iio/light/Makefile
>> +++ b/drivers/iio/light/Makefile
>> @@ -11,6 +11,7 @@ obj-$(CONFIG_GP2AP020A00F)	+= gp2ap020a00f.o
>>   obj-$(CONFIG_HID_SENSOR_ALS)	+= hid-sensor-als.o
>>   obj-$(CONFIG_HID_SENSOR_PROX)	+= hid-sensor-prox.o
>>   obj-$(CONFIG_ISL29125)		+= isl29125.o
>> +obj-$(CONFIG_JSA1212)		+= jsa1212.o
>>   obj-$(CONFIG_SENSORS_LM3533)	+= lm3533-als.o
>>   obj-$(CONFIG_LTR501)		+= ltr501.o
>>   obj-$(CONFIG_SENSORS_TSL2563)	+= tsl2563.o
>> diff --git a/drivers/iio/light/jsa1212.c b/drivers/iio/light/jsa1212.c
>> new file mode 100644
>> index 0000000..29de7e7
>> --- /dev/null
>> +++ b/drivers/iio/light/jsa1212.c
>> @@ -0,0 +1,471 @@
>> +/*
>> + * JSA1212 Ambient Light & Proximity Sensor Driver
>> + *
>> + * Copyright (c) 2014, Intel Corporation.
>> + *
>> + * This program is free software; you can redistribute it and/or modify it
>> + * under the terms and conditions 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.
>> + *
>> + * JSA1212 I2C slave address: 0x44(ADDR tied to GND), 0x45(ADDR tied to VDD)
>> + *
>> + * TODO: Interrupt support, thresholds, range support.
>> + */
>> +
>> +#include <linux/kernel.h>
>> +#include <linux/slab.h>
>> +#include <linux/module.h>
>> +#include <linux/delay.h>
>> +#include <linux/i2c.h>
>> +#include <linux/mutex.h>
>> +#include <linux/acpi.h>
>> +#include <linux/regmap.h>
>> +#include <linux/iio/iio.h>
>> +#include <linux/iio/sysfs.h>
>> +
>> +/* JSA1212 reg address */
>> +#define JSA1212_CONF_REG		0x01
>> +#define JSA1212_INT_REG			0x02
>> +#define JSA1212_PXS_LT_REG		0x03
>> +#define JSA1212_PXS_HT_REG		0x04
>> +#define JSA1212_ALS_TH1_REG		0x05
>> +#define JSA1212_ALS_TH2_REG		0x06
>> +#define JSA1212_ALS_TH3_REG		0x07
>> +#define JSA1212_PXS_DATA_REG		0x08
>> +#define JSA1212_ALS_DT1_REG		0x09
>> +#define JSA1212_ALS_DT2_REG		0x0A
>> +#define JSA1212_ALS_RNG_REG		0x0B
>> +#define JSA1212_MAX_REG			0x0C
>> +
>> +/* JSA1212 reg masks */
>> +#define JSA1212_CONF_MASK		0xFF
>> +#define JSA1212_INT_MASK		0xFF
>> +#define JSA1212_PXS_LT_MASK		0xFF
>> +#define JSA1212_PXS_HT_MASK		0xFF
>> +#define JSA1212_ALS_TH1_MASK		0xFF
>> +#define JSA1212_ALS_TH2_LT_MASK		0x0F
>> +#define JSA1212_ALS_TH2_HT_MASK		0xF0
>> +#define JSA1212_ALS_TH3_MASK		0xFF
>> +#define JSA1212_PXS_DATA_MASK		0xFF
>> +#define JSA1212_ALS_DATA_MASK		0x0FFF
>> +#define JSA1212_ALS_DT1_MASK		0xFF
>> +#define JSA1212_ALS_DT2_MASK		0x0F
>> +#define JSA1212_ALS_RNG_MASK		0x07
>> +
>> +/* JSA1212 CONF REG bits */
>> +#define JSA1212_CONF_PXS_MASK		0x80
>> +#define JSA1212_CONF_PXS_ENABLE		0x80
>> +#define JSA1212_CONF_PXS_DISABLE	0x00
>> +#define JSA1212_CONF_ALS_MASK		0x04
>> +#define JSA1212_CONF_ALS_ENABLE		0x04
>> +#define JSA1212_CONF_ALS_DISABLE	0x00
>> +#define JSA1212_CONF_IRDR_MASK		0x08
>> +/* Proxmity sensing IRDR current sink settings */
>> +#define JSA1212_CONF_IRDR_200MA		0x08
>> +#define JSA1212_CONF_IRDR_100MA		0x00
>> +#define JSA1212_CONF_PXS_SLP_MASK	0x70
>> +#define JSA1212_CONF_PXS_SLP_0MS	0x70
>> +#define JSA1212_CONF_PXS_SLP_12MS	0x60
>> +#define JSA1212_CONF_PXS_SLP_50MS	0x50
>> +#define JSA1212_CONF_PXS_SLP_75MS	0x40
>> +#define JSA1212_CONF_PXS_SLP_100MS	0x30
>> +#define JSA1212_CONF_PXS_SLP_200MS	0x20
>> +#define JSA1212_CONF_PXS_SLP_400MS	0x10
>> +#define JSA1212_CONF_PXS_SLP_800MS	0x00
>> +
>> +/* JSA1212 INT REG bits */
>> +#define JSA1212_INT_CTRL_MASK		0x01
>> +#define JSA1212_INT_CTRL_EITHER		0x00
>> +#define JSA1212_INT_CTRL_BOTH		0x01
>> +#define JSA1212_INT_ALS_PRST_MASK	0x06
>> +#define JSA1212_INT_ALS_PRST_1CONV	0x00
>> +#define JSA1212_INT_ALS_PRST_4CONV	0x02
>> +#define JSA1212_INT_ALS_PRST_8CONV	0x04
>> +#define JSA1212_INT_ALS_PRST_16CONV	0x06
>> +#define JSA1212_INT_ALS_FLAG_MASK	0x08
>> +#define JSA1212_INT_ALS_FLAG_CLR	0x00
>> +#define JSA1212_INT_PXS_PRST_MASK	0x60
>> +#define JSA1212_INT_PXS_PRST_1CONV	0x00
>> +#define JSA1212_INT_PXS_PRST_4CONV	0x20
>> +#define JSA1212_INT_PXS_PRST_8CONV	0x40
>> +#define JSA1212_INT_PXS_PRST_16CONV	0x60
>> +#define JSA1212_INT_PXS_FLAG_MASK	0x80
>> +#define JSA1212_INT_PXS_FLAG_CLR	0x00
>> +
>> +/* JSA1212 ALS RNG REG bits */
>> +#define JSA1212_ALS_RNG_0_2048		0x00
>> +#define JSA1212_ALS_RNG_0_1024		0x01
>> +#define JSA1212_ALS_RNG_0_512		0x02
>> +#define JSA1212_ALS_RNG_0_256		0x03
>> +#define JSA1212_ALS_RNG_0_128		0x04
>> +
>> +/* JSA1212 INT threshold range */
>> +#define JSA1212_ALS_TH_MIN	0x0000
>> +#define JSA1212_ALS_TH_MAX	0x0FFF
>> +#define JSA1212_PXS_TH_MIN	0x00
>> +#define JSA1212_PXS_TH_MAX	0xFF
>> +
>> +#define JSA1212_ALS_DELAY_MS	200
>> +#define JSA1212_PXS_DELAY_MS	100
>> +
>> +#define JSA1212_DRIVER_NAME	"jsa1212"
>> +#define JSA1212_REGMAP_NAME	"jsa1212_regmap"
>> +
>> +enum jsa1212_op_mode {
>> +	JSA1212_OPMODE_ALS_EN,
>> +	JSA1212_OPMODE_PXS_EN,
>> +};
>> +
>> +struct jsa1212_data {
>> +	struct i2c_client *client;
>> +	struct mutex lock;
>> +	u8 als_rng_idx;
>> +	bool als_en; /* ALS enable status */
>> +	bool pxs_en; /* proximity enable status */
>> +	struct regmap *regmap;
>> +};
>> +
>> +/* ALS range idx to val mapping */
>> +static const int jsa1212_als_range_val[] = {2048, 1024, 512, 256, 128,
>> +						128, 128, 128};
>> +
>> +/* Enables or disables ALS function based on status */
>> +static int jsa1212_als_enable(struct jsa1212_data *data, u8 status)
>> +{
>> +	int ret;
>> +
>> +	ret = regmap_update_bits(data->regmap, JSA1212_CONF_REG,
>> +				JSA1212_CONF_ALS_MASK,
>> +				status);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	data->als_en = !!status;
>> +
>> +	return 0;
>> +}
>> +
>> +/* Enables or disables PXS function based on status */
>> +static int jsa1212_pxs_enable(struct jsa1212_data *data, u8 status)
>> +{
>> +	int ret;
>> +
>> +	ret = regmap_update_bits(data->regmap, JSA1212_CONF_REG,
>> +				JSA1212_CONF_PXS_MASK,
>> +				status);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	data->pxs_en = !!status;
>> +
>> +	return 0;
>> +}
>> +
>> +static int jsa1212_read_als_data(struct jsa1212_data *data,
>> +				unsigned int *val)
>> +{
>> +	int ret;
>> +	__le16 als_data;
>> +
>> +	ret = jsa1212_als_enable(data, JSA1212_CONF_ALS_ENABLE);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* Delay for data output */
>> +	msleep(JSA1212_ALS_DELAY_MS);
>> +
>> +	/* Read 12 bit data */
>> +	ret = regmap_bulk_read(data->regmap, JSA1212_ALS_DT1_REG, &als_data, 2);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "als data read err\n");
>> +		goto als_data_read_err;
>> +	}
>> +
>> +	*val = le16_to_cpu(als_data);
>> +
>> +als_data_read_err:
>> +	return jsa1212_als_enable(data, JSA1212_CONF_ALS_DISABLE);
>> +}
>> +
>> +static int jsa1212_read_pxs_data(struct jsa1212_data *data,
>> +				unsigned int *val)
>> +{
>> +	int ret;
>> +	unsigned int pxs_data;
>> +
>> +	ret = jsa1212_pxs_enable(data, JSA1212_CONF_PXS_ENABLE);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	/* Delay for data output */
>> +	msleep(JSA1212_PXS_DELAY_MS);
>> +
>> +	/* Read out all data */
>> +	ret = regmap_read(data->regmap, JSA1212_PXS_DATA_REG, &pxs_data);
>> +	if (ret < 0) {
>> +		dev_err(&data->client->dev, "pxs data read err\n");
>> +		goto pxs_data_read_err;
>> +	}
>> +
>> +	*val = pxs_data & JSA1212_PXS_DATA_MASK;
>> +
>> +pxs_data_read_err:
>> +	return jsa1212_pxs_enable(data, JSA1212_CONF_PXS_DISABLE);
>> +}
>> +
>> +static int jsa1212_read_raw(struct iio_dev *indio_dev,
>> +				struct iio_chan_spec const *chan,
>> +				int *val, int *val2, long mask)
>> +{
>> +	int ret;
>> +	struct jsa1212_data *data = iio_priv(indio_dev);
>> +
>> +	switch (mask) {
>> +	case IIO_CHAN_INFO_RAW:
>> +		mutex_lock(&data->lock);
>> +		switch (chan->type) {
>> +		case IIO_LIGHT:
>> +			ret = jsa1212_read_als_data(data, val);
>> +			break;
>> +		case IIO_PROXIMITY:
>> +			ret = jsa1212_read_pxs_data(data, val);
>> +			break;
>> +		default:
>> +			ret = -EINVAL;
>> +			break;
>> +		}
>> +		mutex_unlock(&data->lock);
>> +		return ret < 0 ? ret : IIO_VAL_INT;
>> +	case IIO_CHAN_INFO_SCALE:
>> +		switch (chan->type) {
>> +		case IIO_LIGHT:
>> +			*val = jsa1212_als_range_val[data->als_rng_idx];
>> +			*val2 = BIT(12); /* Max 12 bit value */
>> +			return IIO_VAL_FRACTIONAL;
>> +		default:
>> +			break;
>> +		}
>> +		break;
>> +	default:
>> +		break;
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static const struct iio_chan_spec jsa1212_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 const struct iio_info jsa1212_info = {
>> +	.driver_module		= THIS_MODULE,
>> +	.read_raw		= &jsa1212_read_raw,
>> +};
>> +
>> +static int jsa1212_chip_init(struct jsa1212_data *data)
>> +{
>> +	int ret;
>> +
>> +	ret = regmap_write(data->regmap, JSA1212_CONF_REG,
>> +				(JSA1212_CONF_PXS_SLP_50MS |
>> +				JSA1212_CONF_IRDR_200MA));
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	ret = regmap_write(data->regmap, JSA1212_INT_REG,
>> +				JSA1212_INT_ALS_PRST_4CONV);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	data->als_rng_idx = JSA1212_ALS_RNG_0_2048;
>> +
>> +	return 0;
>> +}
>> +
>> +static bool jsa1212_is_volatile_reg(struct device *dev, unsigned int reg)
>> +{
>> +	switch (reg) {
>> +	case JSA1212_PXS_DATA_REG:
>> +	case JSA1212_ALS_DT1_REG:
>> +	case JSA1212_ALS_DT2_REG:
>> +	case JSA1212_INT_REG:
>> +		return true;
>> +	default:
>> +		return false;
>> +	}
>> +}
>> +
>> +static struct regmap_config jsa1212_regmap_config = {
>> +	.name =  JSA1212_REGMAP_NAME,
>> +	.reg_bits = 8,
>> +	.val_bits = 8,
>> +	.max_register = JSA1212_MAX_REG,
>> +	.cache_type = REGCACHE_RBTREE,
>> +	.volatile_reg = jsa1212_is_volatile_reg,
>> +};
>> +
>> +static int jsa1212_probe(struct i2c_client *client,
>> +			 const struct i2c_device_id *id)
>> +{
>> +	struct jsa1212_data *data;
>> +	struct iio_dev *indio_dev;
>> +	struct regmap *regmap;
>> +	int ret;
>> +
>> +	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
>> +		return -ENODEV;
>> +
>> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
>> +	if (!indio_dev)
>> +		return -ENOMEM;
>> +
>> +	regmap = devm_regmap_init_i2c(client, &jsa1212_regmap_config);
>> +	if (IS_ERR(regmap)) {
>> +		dev_err(&client->dev, "Regmap initialization failed.\n");
>> +		return PTR_ERR(regmap);
>> +	}
>> +
>> +	data = iio_priv(indio_dev);
>> +
>> +	i2c_set_clientdata(client, indio_dev);
>> +	data->client = client;
>> +	data->regmap = regmap;
>> +
>> +	mutex_init(&data->lock);
>> +
>> +	ret = jsa1212_chip_init(data);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	indio_dev->dev.parent = &client->dev;
>> +	indio_dev->channels = jsa1212_channels;
>> +	indio_dev->num_channels = ARRAY_SIZE(jsa1212_channels);
>> +	indio_dev->name = JSA1212_DRIVER_NAME;
>> +	indio_dev->modes = INDIO_DIRECT_MODE;
>> +
>> +	indio_dev->info = &jsa1212_info;
>> +
>> +	ret = iio_device_register(indio_dev);
>> +	if (ret < 0)
>> +		dev_err(&client->dev, "%s: register device failed\n", __func__);
>> +
>> +	return ret;
>> +}
>> +
>> + /* power off the device */
>> +static int jsa1212_power_off(struct jsa1212_data *data)
>> +{
>> +	int ret;
>> +
>> +	mutex_lock(&data->lock);
>> +
>> +	ret = regmap_update_bits(data->regmap, JSA1212_CONF_REG,
>> +				JSA1212_CONF_ALS_MASK |
>> +				JSA1212_CONF_PXS_MASK,
>> +				JSA1212_CONF_ALS_DISABLE |
>> +				JSA1212_CONF_PXS_DISABLE);
>> +
>> +	if (ret < 0)
>> +		dev_err(&data->client->dev, "power off cmd failed\n");
>> +
>> +	mutex_unlock(&data->lock);
>> +
>> +	return ret;
>> +}
>> +
>> +static int jsa1212_remove(struct i2c_client *client)
>> +{
>> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
>> +	struct jsa1212_data *data = iio_priv(indio_dev);
>> +
>> +	iio_device_unregister(indio_dev);
>> +
>> +	return jsa1212_power_off(data);
>> +}
>> +
>> +#ifdef CONFIG_PM_SLEEP
>> +static int jsa1212_suspend(struct device *dev)
>> +{
>> +	struct jsa1212_data *data;
>> +
>> +	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
>> +
>> +	return jsa1212_power_off(data);
>> +}
>> +
>> +static int jsa1212_resume(struct device *dev)
>> +{
>> +	int ret = 0;
>> +	struct jsa1212_data *data;
>> +
>> +	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
>> +
>> +	mutex_lock(&data->lock);
>> +
>> +	if (data->als_en) {
>> +		ret = jsa1212_als_enable(data, JSA1212_CONF_ALS_ENABLE);
>> +		if (ret < 0) {
>> +			dev_err(dev, "als resume failed\n");
>> +			goto unlock_and_ret;
>> +		}
>> +	}
>> +
>> +	if (data->pxs_en) {
>> +		ret = jsa1212_pxs_enable(data, JSA1212_CONF_PXS_ENABLE);
>> +		if (ret < 0)
>> +			dev_err(dev, "pxs resume failed\n");
>> +	}
>> +
>> +unlock_and_ret:
>> +	mutex_unlock(&data->lock);
>> +	return ret;
>> +}
>> +
>> +static SIMPLE_DEV_PM_OPS(jsa1212_pm_ops, jsa1212_suspend, jsa1212_resume);
>> +
>> +#define JSA1212_PM_OPS (&jsa1212_pm_ops)
>> +#else
>> +#define JSA1212_PM_OPS NULL
>> +#endif
>> +
>> +static const struct acpi_device_id jsa1212_acpi_match[] = {
>> +	{"JSA1212", 0},
>> +	{ },
>> +};
>> +MODULE_DEVICE_TABLE(acpi, jsa1212_acpi_match);
>> +
>> +static const struct i2c_device_id jsa1212_id[] = {
>> +	{ JSA1212_DRIVER_NAME, 0 },
>> +	{ }
>> +};
>> +MODULE_DEVICE_TABLE(i2c, jsa1212_id);
>> +
>> +static struct i2c_driver jsa1212_driver = {
>> +	.driver = {
>> +		.name	= JSA1212_DRIVER_NAME,
>> +		.pm	= JSA1212_PM_OPS,
>> +		.owner	= THIS_MODULE,
>> +		.acpi_match_table = ACPI_PTR(jsa1212_acpi_match),
>> +	},
>> +	.probe		= jsa1212_probe,
>> +	.remove		= jsa1212_remove,
>> +	.id_table	= jsa1212_id,
>> +};
>> +module_i2c_driver(jsa1212_driver);
>> +
>> +MODULE_AUTHOR("Sathya Kuppuswamy <sathyanarayanan.kuppuswamy@linux.intel.com>");
>> +MODULE_DESCRIPTION("JSA1212 proximity/ambient light sensor driver");
>> +MODULE_LICENSE("GPL v2");
>>
>

-- 
Sathyanarayanan Kuppuswamy
Android kernel developer