iio: add APDS9300 ambilent light sensor driver
authorOleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Mon, 22 Jul 2013 13:11:00 +0000 (14:11 +0100)
committerJonathan Cameron <jic23@kernel.org>
Sat, 3 Aug 2013 17:40:37 +0000 (18:40 +0100)
This patch adds IIO driver for APDS9300 ambient light sensor (ALS).
http://www.avagotech.com/docs/AV02-1077EN

The driver allows to read raw data from ADC registers or calculate
lux value. It also can handle threshold interrupt.

Signed-off-by: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Documentation/devicetree/bindings/iio/light/apds9300.txt [new file with mode: 0644]
drivers/iio/light/Kconfig
drivers/iio/light/Makefile
drivers/iio/light/apds9300.c [new file with mode: 0644]

diff --git a/Documentation/devicetree/bindings/iio/light/apds9300.txt b/Documentation/devicetree/bindings/iio/light/apds9300.txt
new file mode 100644 (file)
index 0000000..d6f66c7
--- /dev/null
@@ -0,0 +1,22 @@
+* Avago APDS9300 ambient light sensor
+
+http://www.avagotech.com/docs/AV02-1077EN
+
+Required properties:
+
+  - compatible : should be "avago,apds9300"
+  - reg : the I2C address of the sensor
+
+Optional properties:
+
+  - interrupt-parent : should be the phandle for the interrupt controller
+  - interrupts : interrupt mapping for GPIO IRQ
+
+Example:
+
+apds9300@39 {
+       compatible = "avago,apds9300";
+       reg = <0x39>;
+       interrupt-parent = <&gpio2>;
+       interrupts = <29 8>;
+};
index 3bd29f810e6dfd8b016e3bc067ec1fd97ab7c13a..bf9fa0d7aff9c26d0b4caf22bf25881de868c93d 100644 (file)
@@ -17,6 +17,16 @@ config ADJD_S311
         This driver can also be built as a module.  If so, the module
         will be called adjd_s311.
 
+config APDS9300
+       tristate "APDS9300 ambient light sensor"
+       depends on I2C
+       help
+        Say Y here if you want to build a driver for the Avago APDS9300
+        ambient light sensor.
+
+        To compile this driver as a module, choose M here: the
+        module will be called apds9300.
+
 config HID_SENSOR_ALS
        depends on HID_SENSOR_HUB
        select IIO_BUFFER
index edef939861f02ee4a0cfd594431c50cbf9503eb5..354ee9ab2379a92ba73a486d399e0b243c594ea1 100644 (file)
@@ -4,6 +4,7 @@
 
 # When adding new entries keep the list in alphabetical order
 obj-$(CONFIG_ADJD_S311)                += adjd_s311.o
+obj-$(CONFIG_APDS9300)         += apds9300.o
 obj-$(CONFIG_HID_SENSOR_ALS)   += hid-sensor-als.o
 obj-$(CONFIG_SENSORS_LM3533)   += lm3533-als.o
 obj-$(CONFIG_SENSORS_TSL2563)  += tsl2563.o
diff --git a/drivers/iio/light/apds9300.c b/drivers/iio/light/apds9300.c
new file mode 100644 (file)
index 0000000..66a58bd
--- /dev/null
@@ -0,0 +1,512 @@
+/*
+ * apds9300.c - IIO driver for Avago APDS9300 ambient light sensor
+ *
+ * Copyright 2013 Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/pm.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/interrupt.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/events.h>
+
+#define APDS9300_DRV_NAME "apds9300"
+#define APDS9300_IRQ_NAME "apds9300_event"
+
+/* Command register bits */
+#define APDS9300_CMD   BIT(7) /* Select command register. Must write as 1 */
+#define APDS9300_WORD  BIT(5) /* I2C write/read: if 1 word, if 0 byte */
+#define APDS9300_CLEAR BIT(6) /* Interrupt clear. Clears pending interrupt */
+
+/* Register set */
+#define APDS9300_CONTROL       0x00 /* Control of basic functions */
+#define APDS9300_THRESHLOWLOW  0x02 /* Low byte of low interrupt threshold */
+#define APDS9300_THRESHHIGHLOW 0x04 /* Low byte of high interrupt threshold */
+#define APDS9300_INTERRUPT     0x06 /* Interrupt control */
+#define APDS9300_DATA0LOW      0x0c /* Low byte of ADC channel 0 */
+#define APDS9300_DATA1LOW      0x0e /* Low byte of ADC channel 1 */
+
+/* Power on/off value for APDS9300_CONTROL register */
+#define APDS9300_POWER_ON      0x03
+#define APDS9300_POWER_OFF     0x00
+
+/* Interrupts */
+#define APDS9300_INTR_ENABLE   0x10
+/* Interrupt Persist Function: Any value outside of threshold range */
+#define APDS9300_THRESH_INTR   0x01
+
+#define APDS9300_THRESH_MAX    0xffff /* Max threshold value */
+
+struct apds9300_data {
+       struct i2c_client *client;
+       struct mutex mutex;
+       int power_state;
+       int thresh_low;
+       int thresh_hi;
+       int intr_en;
+};
+
+/* Lux calculation */
+
+/* Calculated values 1000 * (CH1/CH0)^1.4 for CH1/CH0 from 0 to 0.52 */
+static const u16 apds9300_lux_ratio[] = {
+       0, 2, 4, 7, 11, 15, 19, 24, 29, 34, 40, 45, 51, 57, 64, 70, 77, 84, 91,
+       98, 105, 112, 120, 128, 136, 144, 152, 160, 168, 177, 185, 194, 203,
+       212, 221, 230, 239, 249, 258, 268, 277, 287, 297, 307, 317, 327, 337,
+       347, 358, 368, 379, 390, 400,
+};
+
+static unsigned long apds9300_calculate_lux(u16 ch0, u16 ch1)
+{
+       unsigned long lux, tmp;
+
+       /* avoid division by zero */
+       if (ch0 == 0)
+               return 0;
+
+       tmp = DIV_ROUND_UP(ch1 * 100, ch0);
+       if (tmp <= 52) {
+               lux = 3150 * ch0 - (unsigned long)DIV_ROUND_UP_ULL(ch0
+                               * apds9300_lux_ratio[tmp] * 5930ull, 1000);
+       } else if (tmp <= 65) {
+               lux = 2290 * ch0 - 2910 * ch1;
+       } else if (tmp <= 80) {
+               lux = 1570 * ch0 - 1800 * ch1;
+       } else if (tmp <= 130) {
+               lux = 338 * ch0 - 260 * ch1;
+       } else {
+               lux = 0;
+       }
+
+       return lux / 100000;
+}
+
+static int apds9300_get_adc_val(struct apds9300_data *data, int adc_number)
+{
+       int ret;
+       u8 flags = APDS9300_CMD | APDS9300_WORD;
+
+       if (!data->power_state)
+               return -EBUSY;
+
+       /* Select ADC0 or ADC1 data register */
+       flags |= adc_number ? APDS9300_DATA1LOW : APDS9300_DATA0LOW;
+
+       ret = i2c_smbus_read_word_data(data->client, flags);
+       if (ret < 0)
+               dev_err(&data->client->dev,
+                       "failed to read ADC%d value\n", adc_number);
+
+       return ret;
+}
+
+static int apds9300_set_thresh_low(struct apds9300_data *data, int value)
+{
+       int ret;
+
+       if (!data->power_state)
+               return -EBUSY;
+
+       if (value > APDS9300_THRESH_MAX)
+               return -EINVAL;
+
+       ret = i2c_smbus_write_word_data(data->client, APDS9300_THRESHLOWLOW
+                       | APDS9300_CMD | APDS9300_WORD, value);
+       if (ret) {
+               dev_err(&data->client->dev, "failed to set thresh_low\n");
+               return ret;
+       }
+       data->thresh_low = value;
+
+       return 0;
+}
+
+static int apds9300_set_thresh_hi(struct apds9300_data *data, int value)
+{
+       int ret;
+
+       if (!data->power_state)
+               return -EBUSY;
+
+       if (value > APDS9300_THRESH_MAX)
+               return -EINVAL;
+
+       ret = i2c_smbus_write_word_data(data->client, APDS9300_THRESHHIGHLOW
+                       | APDS9300_CMD | APDS9300_WORD, value);
+       if (ret) {
+               dev_err(&data->client->dev, "failed to set thresh_hi\n");
+               return ret;
+       }
+       data->thresh_hi = value;
+
+       return 0;
+}
+
+static int apds9300_set_intr_state(struct apds9300_data *data, int state)
+{
+       int ret;
+       u8 cmd;
+
+       if (!data->power_state)
+               return -EBUSY;
+
+       cmd = state ? APDS9300_INTR_ENABLE | APDS9300_THRESH_INTR : 0x00;
+       ret = i2c_smbus_write_byte_data(data->client,
+                       APDS9300_INTERRUPT | APDS9300_CMD, cmd);
+       if (ret) {
+               dev_err(&data->client->dev,
+                       "failed to set interrupt state %d\n", state);
+               return ret;
+       }
+       data->intr_en = state;
+
+       return 0;
+}
+
+static int apds9300_set_power_state(struct apds9300_data *data, int state)
+{
+       int ret;
+       u8 cmd;
+
+       cmd = state ? APDS9300_POWER_ON : APDS9300_POWER_OFF;
+       ret = i2c_smbus_write_byte_data(data->client,
+                       APDS9300_CONTROL | APDS9300_CMD, cmd);
+       if (ret) {
+               dev_err(&data->client->dev,
+                       "failed to set power state %d\n", state);
+               return ret;
+       }
+       data->power_state = state;
+
+       return 0;
+}
+
+static void apds9300_clear_intr(struct apds9300_data *data)
+{
+       int ret;
+
+       ret = i2c_smbus_write_byte(data->client, APDS9300_CLEAR | APDS9300_CMD);
+       if (ret < 0)
+               dev_err(&data->client->dev, "failed to clear interrupt\n");
+}
+
+static int apds9300_chip_init(struct apds9300_data *data)
+{
+       int ret;
+
+       /* Need to set power off to ensure that the chip is off */
+       ret = apds9300_set_power_state(data, 0);
+       if (ret < 0)
+               goto err;
+       /*
+        * Probe the chip. To do so we try to power up the device and then to
+        * read back the 0x03 code
+        */
+       ret = apds9300_set_power_state(data, 1);
+       if (ret < 0)
+               goto err;
+       ret = i2c_smbus_read_byte_data(data->client,
+                       APDS9300_CONTROL | APDS9300_CMD);
+       if (ret != APDS9300_POWER_ON) {
+               ret = -ENODEV;
+               goto err;
+       }
+       /*
+        * Disable interrupt to ensure thai it is doesn't enable
+        * i.e. after device soft reset
+        */
+       ret = apds9300_set_intr_state(data, 0);
+       if (ret < 0)
+               goto err;
+
+       return 0;
+
+err:
+       dev_err(&data->client->dev, "failed to init the chip\n");
+       return ret;
+}
+
+static int apds9300_read_raw(struct iio_dev *indio_dev,
+               struct iio_chan_spec const *chan, int *val, int *val2,
+               long mask)
+{
+       int ch0, ch1, ret = -EINVAL;
+       struct apds9300_data *data = iio_priv(indio_dev);
+
+       mutex_lock(&data->mutex);
+       switch (chan->type) {
+       case IIO_LIGHT:
+               ch0 = apds9300_get_adc_val(data, 0);
+               if (ch0 < 0) {
+                       ret = ch0;
+                       break;
+               }
+               ch1 = apds9300_get_adc_val(data, 1);
+               if (ch1 < 0) {
+                       ret = ch1;
+                       break;
+               }
+               *val = apds9300_calculate_lux(ch0, ch1);
+               ret = IIO_VAL_INT;
+               break;
+       case IIO_INTENSITY:
+               ret = apds9300_get_adc_val(data, chan->channel);
+               if (ret < 0)
+                       break;
+               *val = ret;
+               ret = IIO_VAL_INT;
+               break;
+       default:
+               break;
+       }
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int apds9300_read_thresh(struct iio_dev *indio_dev, u64 event_code,
+               int *val)
+{
+       struct apds9300_data *data = iio_priv(indio_dev);
+
+       switch (IIO_EVENT_CODE_EXTRACT_DIR(event_code)) {
+       case IIO_EV_DIR_RISING:
+               *val = data->thresh_hi;
+               break;
+       case IIO_EV_DIR_FALLING:
+               *val = data->thresh_low;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static int apds9300_write_thresh(struct iio_dev *indio_dev, u64 event_code,
+               int val)
+{
+       struct apds9300_data *data = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&data->mutex);
+       if (IIO_EVENT_CODE_EXTRACT_DIR(event_code) == IIO_EV_DIR_RISING)
+               ret = apds9300_set_thresh_hi(data, val);
+       else
+               ret = apds9300_set_thresh_low(data, val);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int apds9300_read_interrupt_config(struct iio_dev *indio_dev,
+               u64 event_code)
+{
+       struct apds9300_data *data = iio_priv(indio_dev);
+
+       return data->intr_en;
+}
+
+static int apds9300_write_interrupt_config(struct iio_dev *indio_dev,
+               u64 event_code, int state)
+{
+       struct apds9300_data *data = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&data->mutex);
+       ret = apds9300_set_intr_state(data, state);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static const struct iio_info apds9300_info_no_irq = {
+       .driver_module  = THIS_MODULE,
+       .read_raw       = apds9300_read_raw,
+};
+
+static const struct iio_info apds9300_info = {
+       .driver_module          = THIS_MODULE,
+       .read_raw               = apds9300_read_raw,
+       .read_event_value       = apds9300_read_thresh,
+       .write_event_value      = apds9300_write_thresh,
+       .read_event_config      = apds9300_read_interrupt_config,
+       .write_event_config     = apds9300_write_interrupt_config,
+};
+
+static const struct iio_chan_spec apds9300_channels[] = {
+       {
+               .type = IIO_LIGHT,
+               .channel = 0,
+               .indexed = true,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+       }, {
+               .type = IIO_INTENSITY,
+               .channel = 0,
+               .channel2 = IIO_MOD_LIGHT_BOTH,
+               .indexed = true,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+               .event_mask = (IIO_EV_BIT(IIO_EV_TYPE_THRESH,
+                                         IIO_EV_DIR_RISING) |
+                              IIO_EV_BIT(IIO_EV_TYPE_THRESH,
+                                         IIO_EV_DIR_FALLING)),
+       }, {
+               .type = IIO_INTENSITY,
+               .channel = 1,
+               .channel2 = IIO_MOD_LIGHT_IR,
+               .indexed = true,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+       },
+};
+
+static irqreturn_t apds9300_interrupt_handler(int irq, void *private)
+{
+       struct iio_dev *dev_info = private;
+       struct apds9300_data *data = iio_priv(dev_info);
+
+       iio_push_event(dev_info,
+                      IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,
+                                           IIO_EV_TYPE_THRESH,
+                                           IIO_EV_DIR_EITHER),
+                      iio_get_time_ns());
+
+       apds9300_clear_intr(data);
+
+       return IRQ_HANDLED;
+}
+
+static int apds9300_probe(struct i2c_client *client,
+               const struct i2c_device_id *id)
+{
+       struct apds9300_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;
+
+       ret = apds9300_chip_init(data);
+       if (ret < 0)
+               goto err;
+
+       mutex_init(&data->mutex);
+
+       indio_dev->dev.parent = &client->dev;
+       indio_dev->channels = apds9300_channels;
+       indio_dev->num_channels = ARRAY_SIZE(apds9300_channels);
+       indio_dev->name = APDS9300_DRV_NAME;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+
+       if (client->irq)
+               indio_dev->info = &apds9300_info;
+       else
+               indio_dev->info = &apds9300_info_no_irq;
+
+       if (client->irq) {
+               ret = devm_request_threaded_irq(&client->dev, client->irq,
+                               NULL, apds9300_interrupt_handler,
+                               IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+                               APDS9300_IRQ_NAME, indio_dev);
+               if (ret) {
+                       dev_err(&client->dev, "irq request error %d\n", -ret);
+                       goto err;
+               }
+       }
+
+       ret = iio_device_register(indio_dev);
+       if (ret < 0)
+               goto err;
+
+       return 0;
+
+err:
+       /* Ensure that power off in case of error */
+       apds9300_set_power_state(data, 0);
+       return ret;
+}
+
+static int apds9300_remove(struct i2c_client *client)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(client);
+       struct apds9300_data *data = iio_priv(indio_dev);
+
+       iio_device_unregister(indio_dev);
+
+       /* Ensure that power off and interrupts are disabled */
+       apds9300_set_intr_state(data, 0);
+       apds9300_set_power_state(data, 0);
+
+       return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int apds9300_suspend(struct device *dev)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+       struct apds9300_data *data = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&data->mutex);
+       ret = apds9300_set_power_state(data, 0);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static int apds9300_resume(struct device *dev)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+       struct apds9300_data *data = iio_priv(indio_dev);
+       int ret;
+
+       mutex_lock(&data->mutex);
+       ret = apds9300_set_power_state(data, 1);
+       mutex_unlock(&data->mutex);
+
+       return ret;
+}
+
+static SIMPLE_DEV_PM_OPS(apds9300_pm_ops, apds9300_suspend, apds9300_resume);
+#define APDS9300_PM_OPS (&apds9300_pm_ops)
+#else
+#define APDS9300_PM_OPS NULL
+#endif
+
+static struct i2c_device_id apds9300_id[] = {
+       { APDS9300_DRV_NAME, 0 },
+       { }
+};
+
+MODULE_DEVICE_TABLE(i2c, apds9300_id);
+
+static struct i2c_driver apds9300_driver = {
+       .driver = {
+               .name   = APDS9300_DRV_NAME,
+               .owner  = THIS_MODULE,
+               .pm     = APDS9300_PM_OPS,
+       },
+       .probe          = apds9300_probe,
+       .remove         = apds9300_remove,
+       .id_table       = apds9300_id,
+};
+
+module_i2c_driver(apds9300_driver);
+
+MODULE_AUTHOR("Kravchenko Oleksandr <o.v.kravchenko@globallogic.com>");
+MODULE_AUTHOR("GlobalLogic inc.");
+MODULE_DESCRIPTION("APDS9300 ambient light photo sensor driver");
+MODULE_LICENSE("GPL");