iio: ak8975: Added ACPI enumeration

Added capability so that this device can be enumerated via ACPI.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 0f1ca53..f5c1d41 100644 (file)
--- a/drivers/iio/magnetometer/ak8975.c
+++ b/drivers/iio/magnetometer/ak8975.c
@@ -31,6 +31,7 @@
 #include <linux/bitops.h>
 #include <linux/gpio.h>
 #include <linux/of_gpio.h>
+#include <linux/acpi.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
@@ -475,6 +476,27 @@ static const struct iio_info ak8975_info = {
        .driver_module = THIS_MODULE,
 };
 
+static const struct acpi_device_id ak_acpi_match[] = {
+       {"AK8975", AK8975},
+       {"AK8963", AK8963},
+       {"INVN6500", AK8963},
+       { },
+};
+MODULE_DEVICE_TABLE(acpi, ak_acpi_match);
+
+static char *ak8975_match_acpi_device(struct device *dev,
+                               enum asahi_compass_chipset *chipset)
+{
+       const struct acpi_device_id *id;
+
+       id = acpi_match_device(dev->driver->acpi_match_table, dev);
+       if (!id)
+               return NULL;
+       *chipset = (int)id->driver_data;
+
+       return (char *)dev_name(dev);
+}
+
 static int ak8975_probe(struct i2c_client *client,
                        const struct i2c_device_id *id)
 {
@@ -482,6 +504,7 @@ static int ak8975_probe(struct i2c_client *client,
        struct iio_dev *indio_dev;
        int eoc_gpio;
        int err;
+       char *name = NULL;
 
        /* Grab and set up the supplied GPIO. */
        if (client->dev.platform_data)
@@ -519,8 +542,18 @@ static int ak8975_probe(struct i2c_client *client,
        data->eoc_gpio = eoc_gpio;
        data->eoc_irq = 0;
 
-       data->chipset = (enum asahi_compass_chipset)(id->driver_data);
-       dev_dbg(&client->dev, "Asahi compass chip %s\n", id->name);
+       /* id will be NULL when enumerated via ACPI */
+       if (id) {
+               data->chipset =
+                       (enum asahi_compass_chipset)(id->driver_data);
+               name = (char *) id->name;
+       } else if (ACPI_HANDLE(&client->dev))
+               name = ak8975_match_acpi_device(&client->dev, &data->chipset);
+       else {
+               err = -ENOSYS;
+               goto exit_free_iio;
+       }
+       dev_dbg(&client->dev, "Asahi compass chip %s\n", name);
 
        /* Perform some basic start-of-day setup of the device. */
        err = ak8975_setup(client);
@@ -538,7 +571,7 @@ static int ak8975_probe(struct i2c_client *client,
        indio_dev->info = &ak8975_info;
        indio_dev->name = id->name;
        indio_dev->modes = INDIO_DIRECT_MODE;
-
+       indio_dev->name = name;
        err = iio_device_register(indio_dev);
        if (err < 0)
                goto exit_free_iio;
@@ -593,6 +626,7 @@ static struct i2c_driver ak8975_driver = {
        .driver = {
                .name   = "ak8975",
                .of_match_table = ak8975_of_match,
+               .acpi_match_table = ACPI_PTR(ak_acpi_match),
        },
        .probe          = ak8975_probe,
        .remove         = ak8975_remove,