Merge tag 'iio-fixes-for-3.16a' of git://git.kernel.org/pub/scm/linux/kernel/git...

[karo-tx-linux.git] / drivers / iio / magnetometer / ak8975.c

diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c
index 2a524acabec8d5f804186b0ac5d72db7a1c6a4a9..ea08313af0d2f5eeccf654e4081ad1bd5427df6e 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>
@@ -85,7 +86,14 @@
 #define AK8975_MAX_CONVERSION_TIMEOUT  500
 #define AK8975_CONVERSION_DONE_POLL_TIME 10
 #define AK8975_DATA_READY_TIMEOUT      ((100*HZ)/1000)
-#define RAW_TO_GAUSS(asa) ((((asa) + 128) * 3000) / 256)
+#define RAW_TO_GAUSS_8975(asa) ((((asa) + 128) * 3000) / 256)
+#define RAW_TO_GAUSS_8963(asa) ((((asa) + 128) * 6000) / 256)
+
+/* Compatible Asahi Kasei Compass parts */
+enum asahi_compass_chipset {
+       AK8975,
+       AK8963,
+};
 
 /*
  * Per-instance context data for the device.
@@ -101,6 +109,7 @@ struct ak8975_data {
        int                     eoc_irq;
        wait_queue_head_t       data_ready_queue;
        unsigned long           flags;
+       enum asahi_compass_chipset chipset;
 };
 
 static const int ak8975_index_to_reg[] = {
@@ -272,9 +281,21 @@ static int ak8975_setup(struct i2c_client *client)
  * Since ASA doesn't change, we cache the resultant scale factor into the
  * device context in ak8975_setup().
  */
-       data->raw_to_gauss[0] = RAW_TO_GAUSS(data->asa[0]);
-       data->raw_to_gauss[1] = RAW_TO_GAUSS(data->asa[1]);
-       data->raw_to_gauss[2] = RAW_TO_GAUSS(data->asa[2]);
+       if (data->chipset == AK8963) {
+               /*
+                * H range is +-8190 and magnetometer range is +-4912.
+                * So HuT using the above explanation for 8975,
+                * 4912/8190 = ~ 6/10.
+                * So the Hadj should use 6/10 instead of 3/10.
+                */
+               data->raw_to_gauss[0] = RAW_TO_GAUSS_8963(data->asa[0]);
+               data->raw_to_gauss[1] = RAW_TO_GAUSS_8963(data->asa[1]);
+               data->raw_to_gauss[2] = RAW_TO_GAUSS_8963(data->asa[2]);
+       } else {
+               data->raw_to_gauss[0] = RAW_TO_GAUSS_8975(data->asa[0]);
+               data->raw_to_gauss[1] = RAW_TO_GAUSS_8975(data->asa[1]);
+               data->raw_to_gauss[2] = RAW_TO_GAUSS_8975(data->asa[2]);
+       }
 
        return 0;
 }
@@ -448,6 +469,27 @@ 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)
 {
@@ -455,6 +497,7 @@ 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)
@@ -492,6 +535,19 @@ static int ak8975_probe(struct i2c_client *client,
        data->eoc_gpio = eoc_gpio;
        data->eoc_irq = 0;
 
+       /* 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);
        if (err < 0) {
@@ -506,9 +562,8 @@ static int ak8975_probe(struct i2c_client *client,
        indio_dev->channels = ak8975_channels;
        indio_dev->num_channels = ARRAY_SIZE(ak8975_channels);
        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;
@@ -545,7 +600,8 @@ static int ak8975_remove(struct i2c_client *client)
 }
 
 static const struct i2c_device_id ak8975_id[] = {
-       {"ak8975", 0},
+       {"ak8975", AK8975},
+       {"ak8963", AK8963},
        {}
 };
 
@@ -562,6 +618,7 @@ 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,