drivers/misc/apds9802als.c: ALS drivers for the apds9802als
anantha [Tue, 26 Oct 2010 21:22:41 +0000 (14:22 -0700)]
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@intel.com>
[The 4K and 64K in the hw spec actually means 4095 (12bit) and 65535 (16bit).]
Signed-off-by: Hong Liu <hong.liu@intel.com>
[Updated to match the ALS light API interface convention from Samu]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/misc/Kconfig
drivers/misc/Makefile
drivers/misc/apds9802als.c [new file with mode: 0644]

index 477a943..6d7665c 100644 (file)
@@ -285,6 +285,16 @@ 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
index 2ecdd32..4be5c6f 100644 (file)
@@ -25,6 +25,7 @@ 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-$(CONFIG_ISL29020)         += isl29020.o
 obj-$(CONFIG_SENSORS_TSL2550)  += tsl2550.o
diff --git a/drivers/misc/apds9802als.c b/drivers/misc/apds9802als.c
new file mode 100644 (file)
index 0000000..fbe4960
--- /dev/null
@@ -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_lux0_input_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(lux0_sensor_range, S_IRUGO | S_IWUSR,
+       als_sensing_range_show, als_sensing_range_store);
+static DEVICE_ATTR(lux0_input, S_IRUGO, als_lux0_input_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_lux0_sensor_range.attr,
+       &dev_attr_lux0_input.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\n");
+               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@intel.com");
+MODULE_DESCRIPTION("Avago apds9802als ALS Driver");
+MODULE_LICENSE("GPL v2");