[PATCH] Add ALS drivers for the apds9802als

From: Alan Cox
Date: Tue Sep 28 2010 - 12:45:13 EST


From: anantha <anantha.narayanan@xxxxxxxxx>

This adds support for the ADPS9802ALS sensor.

Cleanup by Alan Cox
- move mutexes to cover more things
- report I/O errors back to user space
- report range and values in LUX

Signed-off-by: Anantha Narayanan <anantha.narayanan@xxxxxxxxx>
[The 4K and 64K in the hw spec acutally means 4095 (12bit) and 65535 (16bit).]
Signed-off-by: Hong Liu <hong.liu@xxxxxxxxx>
Signed-off-by: Alan Cox <alan@xxxxxxxxxxxxxxx>
---

drivers/misc/Kconfig | 10 +
drivers/misc/Makefile | 1
drivers/misc/apds9802als.c | 308 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 319 insertions(+), 0 deletions(-)
create mode 100644 drivers/misc/apds9802als.c


diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 53b21ff..d6ec9ce 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -293,6 +293,16 @@ config SGI_GRU_DEBUG
This option enables addition debugging code for the SGI GRU driver. If
you are unsure, say N.

+config APDS9802ALS
+ tristate "Medfield Avago APDS9802 ALS Sensor module"
+ depends on I2C
+ help
+ If you say yes here you get support for the ALS APDS9802 ambient
+ light sensor.
+
+ This driver can also be built as a module. If so, the module
+ will be called apds9802als.
+
config ISL29003
tristate "Intersil ISL29003 ambient light sensor"
depends on I2C && SYSFS
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 4c771a2..0e5f2a5 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_SGI_XP) += sgi-xp/
obj-$(CONFIG_SGI_GRU) += sgi-gru/
obj-$(CONFIG_CS5535_MFGPT) += cs5535-mfgpt.o
obj-$(CONFIG_HP_ILO) += hpilo.o
+obj-$(CONFIG_APDS9802ALS) += apds9802als.o
obj-$(CONFIG_ISL29003) += isl29003.o
obj-$(CONFIG_SENSORS_TSL2550) += tsl2550.o
obj-$(CONFIG_EP93XX_PWM) += ep93xx_pwm.o
diff --git a/drivers/misc/apds9802als.c b/drivers/misc/apds9802als.c
new file mode 100644
index 0000000..a52270d
--- /dev/null
+++ b/drivers/misc/apds9802als.c
@@ -0,0 +1,308 @@
+/*
+ * apds9802als.c - apds9802 ALS Driver
+ *
+ * Copyright (C) 2009 Intel Corp
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/sysfs.h>
+#include <linux/hwmon-sysfs.h>
+
+#define ALS_MIN_RANGE_VAL 1
+#define ALS_MAX_RANGE_VAL 2
+#define POWER_STA_ENABLE 1
+#define POWER_STA_DISABLE 0
+#define APDS9802ALS_I2C_ADDR 0x29
+
+#define DRIVER_NAME "apds9802als"
+
+struct als_data {
+ struct device *hwmon_dev;
+ bool needresume;
+ struct mutex mutex;
+};
+
+static ssize_t als_sensing_range_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ int val;
+
+ val = i2c_smbus_read_byte_data(client, 0x81);
+ if (val < 0)
+ return val;
+ if (val & 1)
+ return sprintf(buf, "4095\n");
+ else
+ return sprintf(buf, "65535\n");
+}
+
+static ssize_t als_lux_input0_data_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct als_data *data = i2c_get_clientdata(client);
+ unsigned int ret_val;
+ int temp;
+
+ /* Protect against parallel reads */
+ mutex_lock(&data->mutex);
+ temp = i2c_smbus_read_byte_data(client, 0x8C);/*LSB data*/
+ if (temp < 0) {
+ ret_val = temp;
+ goto failed;
+ }
+ ret_val = i2c_smbus_read_byte_data(client, 0x8D);/*MSB data*/
+ if (ret_val < 0)
+ goto failed;
+ mutex_unlock(&data->mutex);
+ ret_val = (ret_val << 8) | temp;
+ return sprintf(buf, "%d\n", ret_val);
+failed:
+ mutex_unlock(&data->mutex);
+ return ret_val;
+}
+
+static ssize_t als_sensing_range_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct als_data *data = i2c_get_clientdata(client);
+ unsigned int ret_val;
+ unsigned long val;
+
+ if (strict_strtoul(buf, 10, &val))
+ return -EINVAL;
+
+ if (val < 4096)
+ val = 1;
+ else if (val < 65536)
+ val = 2;
+ else
+ return -ERANGE;
+
+ /* Make sure nobody else reads/modifies/writes 0x81 while we
+ are active */
+
+ mutex_lock(&data->mutex);
+
+ ret_val = i2c_smbus_read_byte_data(client, 0x81);
+ if (ret_val < 0)
+ goto fail;
+
+ /* Reset the bits before setting them */
+ ret_val = ret_val & 0xFA;
+
+ if (val == 1) /* Setting the continous measurement up to 4k LUX */
+ ret_val = (ret_val | 0x05);
+ else /* Setting the continous measurement up to 64k LUX*/
+ ret_val = (ret_val | 0x04);
+
+ ret_val = i2c_smbus_write_byte_data(client, 0x81, ret_val);
+ if (ret_val >= 0) {
+ /* All OK */
+ mutex_unlock(&data->mutex);
+ return count;
+ }
+fail:
+ mutex_unlock(&data->mutex);
+ return ret_val;
+}
+
+static ssize_t als_power_status_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ int ret_val;
+ ret_val = i2c_smbus_read_byte_data(client, 0x80);
+ if (ret_val < 0)
+ return ret_val;
+ ret_val = ret_val & 0x01;
+ return sprintf(buf, "%d\n", ret_val);
+}
+
+static int als_set_power_state(struct i2c_client *client, bool on_off)
+{
+ int ret_val;
+ struct als_data *data = i2c_get_clientdata(client);
+
+ mutex_lock(&data->mutex);
+ ret_val = i2c_smbus_read_byte_data(client, 0x80);
+ if (ret_val < 0)
+ goto fail;
+ if (on_off)
+ ret_val = ret_val | 0x01;
+ else
+ ret_val = ret_val & 0xFE;
+ ret_val = i2c_smbus_write_byte_data(client, 0x80, ret_val);
+fail:
+ mutex_unlock(&data->mutex);
+ return ret_val;
+}
+
+static ssize_t als_power_status_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct als_data *data = i2c_get_clientdata(client);
+ unsigned long val;
+ int ret_val;
+
+ if (strict_strtoul(buf, 10, &val))
+ return -EINVAL;
+ if (val == POWER_STA_ENABLE) {
+ ret_val = als_set_power_state(client, true);
+ data->needresume = true;
+ } else if (val == POWER_STA_DISABLE) {
+ ret_val = als_set_power_state(client, false);
+ data->needresume = false;
+ } else
+ return -EINVAL;
+ if (ret_val < 0)
+ return ret_val;
+ return count;
+}
+
+static DEVICE_ATTR(sensing_range, S_IRUGO | S_IWUSR,
+ als_sensing_range_show, als_sensing_range_store);
+static DEVICE_ATTR(lux_input0, S_IRUGO, als_lux_input0_data_show, NULL);
+static DEVICE_ATTR(power_state, S_IRUGO | S_IWUSR,
+ als_power_status_show, als_power_status_store);
+
+static struct attribute *mid_att_als[] = {
+ &dev_attr_sensing_range.attr,
+ &dev_attr_lux_input0.attr,
+ &dev_attr_power_state.attr,
+ NULL
+};
+
+static struct attribute_group m_als_gr = {
+ .name = "apds9802als",
+ .attrs = mid_att_als
+};
+
+static int als_set_default_config(struct i2c_client *client)
+{
+ int ret_val;
+ /* Write the command and then switch on */
+ ret_val = i2c_smbus_write_byte_data(client, 0x80, 0x01);
+ if (ret_val < 0) {
+ dev_err(&client->dev, "failed default switch on write\n");
+ return ret_val;
+ }
+ /* Continous from 1Lux to 64k Lux */
+ ret_val = i2c_smbus_write_byte_data(client, 0x81, 0x04);
+ if (ret_val < 0)
+ dev_err(&client->dev, "failed default LUX on write\n");
+ return ret_val;
+}
+
+static int apds9802als_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int res;
+ struct als_data *data;
+
+ data = kzalloc(sizeof(struct als_data), GFP_KERNEL);
+ if (data == NULL) {
+ dev_err(&client->dev, "Memory allocation failed");
+ return -ENOMEM;
+ }
+ i2c_set_clientdata(client, data);
+ res = sysfs_create_group(&client->dev.kobj, &m_als_gr);
+ if (res) {
+ dev_err(&client->dev, "device create file failed\n");
+ goto als_error1;
+ }
+ dev_info(&client->dev,
+ "%s apds9802als: ALS chip found\n", client->name);
+ als_set_default_config(client);
+ data->needresume = true;
+ mutex_init(&data->mutex);
+ return res;
+als_error1:
+ i2c_set_clientdata(client, NULL);
+ kfree(data);
+ return res;
+}
+
+static int apds9802als_remove(struct i2c_client *client)
+{
+ struct als_data *data = i2c_get_clientdata(client);
+ sysfs_remove_group(&client->dev.kobj, &m_als_gr);
+ kfree(data);
+ return 0;
+}
+
+static int apds9802als_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+ als_set_power_state(client, false);
+ return 0;
+}
+
+static int apds9802als_resume(struct i2c_client *client)
+{
+ struct als_data *data = i2c_get_clientdata(client);
+
+ if (data->needresume == true)
+ als_set_power_state(client, true);
+ return 0;
+}
+
+static struct i2c_device_id apds9802als_id[] = {
+ { DRIVER_NAME, 0 },
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, apds9802als_id);
+
+static struct i2c_driver apds9802als_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ },
+ .probe = apds9802als_probe,
+ .remove = apds9802als_remove,
+ .suspend = apds9802als_suspend,
+ .resume = apds9802als_resume,
+ .id_table = apds9802als_id,
+};
+
+static int __init sensor_apds9802als_init(void)
+{
+ return i2c_add_driver(&apds9802als_driver);
+}
+
+static void __exit sensor_apds9802als_exit(void)
+{
+ i2c_del_driver(&apds9802als_driver);
+}
+module_init(sensor_apds9802als_init);
+module_exit(sensor_apds9802als_exit);
+
+MODULE_AUTHOR("Anantha Narayanan <Anantha.Narayanan@xxxxxxxxx");
+MODULE_DESCRIPTION("Avago apds9802als ALS Driver");
+MODULE_LICENSE("GPL v2");

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