toshiba_acpi: Add IIO interface for accelerometer axis data

This patch adds the accelerometer axis data to the IIO subsystem.

Currently reporting the X, Y and Z values, as no other data can be
queried given the fact that the accelerometer chip itself is hidden
behind the Toshiba proprietary interface.

Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index c06bb85..633fc5c 100644 (file)
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -669,6 +669,7 @@ config ACPI_TOSHIBA
        depends on SERIO_I8042 || SERIO_I8042 = n
        depends on ACPI_VIDEO || ACPI_VIDEO = n
        depends on RFKILL || RFKILL = n
+       depends on IIO
        select INPUT_POLLDEV
        select INPUT_SPARSEKMAP
        ---help---

diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
index 01e12d2..bd9b346 100644 (file)
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -53,6 +53,7 @@
 #include <linux/uaccess.h>
 #include <linux/miscdevice.h>
 #include <linux/rfkill.h>
+#include <linux/iio/iio.h>
 #include <linux/toshiba.h>
 #include <acpi/video.h>
 
@@ -134,6 +135,7 @@ MODULE_LICENSE("GPL");
 
 /* Field definitions */
 #define HCI_ACCEL_MASK                 0x7fff
+#define HCI_ACCEL_DIRECTION_MASK       0x8000
 #define HCI_HOTKEY_DISABLE             0x0b
 #define HCI_HOTKEY_ENABLE              0x09
 #define HCI_HOTKEY_SPECIAL_FUNCTIONS   0x10
@@ -178,6 +180,7 @@ struct toshiba_acpi_dev {
        struct led_classdev eco_led;
        struct miscdevice miscdev;
        struct rfkill *wwan_rfk;
+       struct iio_dev *indio_dev;
 
        int force_fan;
        int last_key_event;
@@ -2420,6 +2423,81 @@ static void toshiba_acpi_kbd_bl_work(struct work_struct *work)
 }
 
 /*
+ * IIO device
+ */
+
+enum toshiba_iio_accel_chan {
+       AXIS_X,
+       AXIS_Y,
+       AXIS_Z
+};
+
+static int toshiba_iio_accel_get_axis(enum toshiba_iio_accel_chan chan)
+{
+       u32 xyval, zval;
+       int ret;
+
+       ret = toshiba_accelerometer_get(toshiba_acpi, &xyval, &zval);
+       if (ret < 0)
+               return ret;
+
+       switch (chan) {
+       case AXIS_X:
+               return xyval & HCI_ACCEL_DIRECTION_MASK ?
+                       -(xyval & HCI_ACCEL_MASK) : xyval & HCI_ACCEL_MASK;
+       case AXIS_Y:
+               return (xyval >> HCI_MISC_SHIFT) & HCI_ACCEL_DIRECTION_MASK ?
+                       -((xyval >> HCI_MISC_SHIFT) & HCI_ACCEL_MASK) :
+                       (xyval >> HCI_MISC_SHIFT) & HCI_ACCEL_MASK;
+       case AXIS_Z:
+               return zval & HCI_ACCEL_DIRECTION_MASK ?
+                       -(zval & HCI_ACCEL_MASK) : zval & HCI_ACCEL_MASK;
+       }
+
+       return ret;
+}
+
+static int toshiba_iio_accel_read_raw(struct iio_dev *indio_dev,
+                                     struct iio_chan_spec const *chan,
+                                     int *val, int *val2, long mask)
+{
+       int ret;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+               ret = toshiba_iio_accel_get_axis(chan->channel);
+               if (ret == -EIO || ret == -ENODEV)
+                       return ret;
+
+               *val = ret;
+
+               return IIO_VAL_INT;
+       }
+
+       return -EINVAL;
+}
+
+#define TOSHIBA_IIO_ACCEL_CHANNEL(axis, chan) { \
+       .type = IIO_ACCEL, \
+       .modified = 1, \
+       .channel = chan, \
+       .channel2 = IIO_MOD_##axis, \
+       .output = 1, \
+       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+}
+
+static const struct iio_chan_spec toshiba_iio_accel_channels[] = {
+       TOSHIBA_IIO_ACCEL_CHANNEL(X, AXIS_X),
+       TOSHIBA_IIO_ACCEL_CHANNEL(Y, AXIS_Y),
+       TOSHIBA_IIO_ACCEL_CHANNEL(Z, AXIS_Z),
+};
+
+static const struct iio_info toshiba_iio_accel_info = {
+       .driver_module = THIS_MODULE,
+       .read_raw = &toshiba_iio_accel_read_raw,
+};
+
+/*
  * Misc device
  */
 static int toshiba_acpi_smm_bridge(SMMRegisters *regs)
@@ -2904,6 +2982,11 @@ static int toshiba_acpi_remove(struct acpi_device *acpi_dev)
 
        remove_toshiba_proc_entries(dev);
 
+       if (dev->accelerometer_supported && dev->indio_dev) {
+               iio_device_unregister(dev->indio_dev);
+               iio_device_free(dev->indio_dev);
+       }
+
        if (dev->sysfs_created)
                sysfs_remove_group(&dev->acpi_dev->dev.kobj,
                                   &toshiba_attr_group);
@@ -3051,6 +3134,30 @@ static int toshiba_acpi_add(struct acpi_device *acpi_dev)
        dev->touchpad_supported = !ret;
 
        toshiba_accelerometer_available(dev);
+       if (dev->accelerometer_supported) {
+               dev->indio_dev = iio_device_alloc(sizeof(*dev));
+               if (!dev->indio_dev) {
+                       pr_err("Unable to allocate iio device\n");
+                       goto iio_error;
+               }
+
+               pr_info("Registering Toshiba accelerometer iio device\n");
+
+               dev->indio_dev->info = &toshiba_iio_accel_info;
+               dev->indio_dev->name = "Toshiba accelerometer";
+               dev->indio_dev->dev.parent = &acpi_dev->dev;
+               dev->indio_dev->modes = INDIO_DIRECT_MODE;
+               dev->indio_dev->channels = toshiba_iio_accel_channels;
+               dev->indio_dev->num_channels =
+                                       ARRAY_SIZE(toshiba_iio_accel_channels);
+
+               ret = iio_device_register(dev->indio_dev);
+               if (ret < 0) {
+                       pr_err("Unable to register iio device\n");
+                       iio_device_free(dev->indio_dev);
+               }
+       }
+iio_error:
 
        toshiba_usb_sleep_charge_available(dev);