[PATCH v3 1/3] toshiba_acpi: Add IIO interface for accelerometer axis data

From: Azael Avalos
Date: Mon Jun 27 2016 - 21:48:20 EST


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@xxxxxxxxx>
---
drivers/platform/x86/toshiba_acpi.c | 107 ++++++++++++++++++++++++++++++++++++
1 file changed, 107 insertions(+)

diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
index 01e12d2..bd9b346a 100644
--- 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);

--
2.8.4