[SOLVED] Accelerometer help needed - Arch Linux - Kernel 3.4

[Padfoots]

Hi,
I am trying to get the accelerometer working on my Acer Iconia Tab W501
In windows, it reported as a BMA150 device, so I have that driver loading on boot.
After months of googling and making a mess in /sys, I still have not got the device working. I was working under the assumption that the device hangs off the i2c bus, but a "lucky google" today uncovered that it is showing up through acpi - acpid is present in my daemons array of rc.conf and the kernel module acer_wmi is also loaded.
The device is certainly sending signals to the kernel. Upon boot, dmesg ends up as follows:

[   11.689709] ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
[   12.108374] EXT4-fs (sda2): re-mounted. Opts: commit=0
[   12.148026] EXT4-fs (sda3): re-mounted. Opts: commit=0
[   17.759006] FS-Cache: Loaded
[   17.780371] FS-Cache: Netfs 'cifs' registered for caching
[   17.816097] CIFS VFS: default security mechanism requested.  The default security mechanism will be upgraded from ntlm to ntlmv2 in kernel release 3.3
[   22.459133] wlan0: no IPv6 routers present

Now, if I rotate the device, and run dmesg again, I have the following:

[ 1255.189705] acer_wmi: Unknown function number - 5 - 1
[ 1257.363688] acer_wmi: Unknown function number - 5 - 1
[ 1268.268809] acer_wmi: Unknown function number - 5 - 1
[ 1268.409270] acer_wmi: Unknown function number - 5 - 1
[ 1308.653700] acer_wmi: Unknown function number - 5 - 1
[ 1308.784623] acer_wmi: Unknown function number - 5 - 1

acpi -V does not show the device:

Battery 0: Full, 100%
Battery 0: design capacity 2865 mAh, last full capacity 2678 mAh = 93%
Adapter 0: on-line
Thermal 0: ok, 59.0 degrees C
Thermal 0: trip point 0 switches to mode critical at temperature 87.0 degrees C
Thermal 0: trip point 1 switches to mode passive at temperature 77.0 degrees C
Cooling 0: LCD 0 of 9
Cooling 1: Processor 0 of 3
Cooling 2: Processor 0 of 10

nor is it configured on boot - dmesg | grep ACPI:

[    0.404389] pnp: PnP ACPI init
[    0.404443] ACPI: bus type pnp registered
[    0.405020] pnp 00:00: Plug and Play ACPI device, IDs PNP0a08 PNP0a03 (active)
[    0.405295] system 00:01: Plug and Play ACPI device, IDs PNP0c02 (active)
[    0.405829] pnp 00:02: Plug and Play ACPI device, IDs PNP0103 (active)
[    0.406106] pnp 00:03: Plug and Play ACPI device, IDs PNP0200 (active)
[    0.406268] pnp 00:04: Plug and Play ACPI device, IDs PNP0c04 (active)
[    0.406514] pnp 00:05: Plug and Play ACPI device, IDs PNP0b00 (active)
[    0.406613] pnp 00:06: Plug and Play ACPI device, IDs PNP0800 (active)
[    0.406774] pnp 00:07: Plug and Play ACPI device, IDs PNP0303 (active)
[    0.407104] system 00:08: Plug and Play ACPI device, IDs PNP0c02 (active)
[    0.407390] system 00:09: Plug and Play ACPI device, IDs PNP0c01 (active)
[    0.408373] pnp: PnP ACPI: found 10 devices
[    0.408377] ACPI: ACPI bus type pnp unregistered
[    4.684770] ACPI: Power Button [PWRB]
[    4.685381] ACPI: acpi_idle registered with cpuidle
[    4.686148] ACPI: Lid Switch [LID]
[    4.692517] ACPI: Power Button [PWRF]
[    4.696710] [Firmware Bug]: ACPI: No _BQC method, cannot determine initial brightness
[    4.719486] ACPI: Video Device [VGA] (multi-head: yes  rom: no  post: no)
[    4.729977] ACPI: AC Adapter [AC0] (on-line)
[    4.746949] ACPI: Battery Slot [BAT0] (battery present)
[    4.824909] ACPI: Thermal Zone [THRM] (61 C)
[    5.220895] acer_wmi: Acer Laptop ACPI-WMI Extras

Yet, running acpi_listen generates the following when the tablet is rotated:

 PNP0C14:00 000000bc 00000000
 PNP0C14:00 000000bc 00000000
 PNP0C14:00 000000bc 00000000
 PNP0C14:00 000000bc 00000000

So, it would seem the device is working and sending data to the kernel/drivers, it appears some config is needed to get it properly recognised and an entry in /dev generated.
Really hoping there is an acpi expert around who may be able to help me get the device properly recognised and configures, ideally, as a /dev/input/js*
Cheers.

[shellscriptcoder]

Just to clarify... Did you already run

# modprobe -v acer_wmi

?

[Padfoots]

Just to clarify... Did you already run

# modprobe -v acer_wmi

?

The module is auto loaded on boot. However, the following is output when I:

# rmmod acer_wmi
# modprobe -v acer_wmi
insmod /lib/modules/3.4.0-1-ARCH/kernel/drivers/platform/x86/acer-wmi.ko.gz

# dmesg
......
[  353.064277] acer_wmi: Acer Laptop ACPI-WMI Extras
[  353.064450] acer_wmi: Function bitmap for Communication Button: 0x841
[  353.064467] acer_wmi: Brightness must be controlled by acpi video driver
[  353.067279] input: Acer WMI hotkeys as /devices/virtual/input/input14

[waterhead]

Are you just trying to rotate the screen when you rotate the tablet? I have accomplished this on my Azpen X1 tablet. It was originally a Windows 7 tablet, so your solution may be different. I found that when using a Gnome based desktop, that the tablet would switch workspaces when rotated. I then created four scripts to rotate the screen in the four positions, and then substituted them for the workspace shortcuts.

I made an extensive thread about it here:

Rotating Screen/Touchpad On Linux

[Padfoots]

Are you just trying to rotate the screen when you rotate the tablet? I have accomplished this on my Azpen X1 tablet. It was originally a Windows 7 tablet, so your solution may be different. I found that when using a Gnome based desktop, that the tablet would switch workspaces when rotated. I then created four scripts to rotate the screen in the four positions, and then substituted them for the workspace shortcuts.

Hi Waterhead,

That is not the issue I am having. The issue is getting the accelerometer to work in the first place. It is sending data through the kernel, hence the error messages I am getting, but it it not properly recognised and configured as a device for me to even link turning the device with rotating the screen.

Thankyou anyway, but what I need is help getting the device properly recognised and configured.

Thanks.

[shellscriptcoder]

Ah. I may have found something - did you apply this patch to drivers/platform/x86/acer-wmi.c ?

diff --git a/drivers/platform/x86/acer-wmi.c b/drivers/platform/x86/acer-wmi.c
index c1a3fd8..edb6bad 100644
--- a/drivers/platform/x86/acer-wmi.c
+++ b/drivers/platform/x86/acer-wmi.c
@@ -95,6 +95,7 @@ MODULE_ALIAS("wmi:676AA15E-6A47-4D9F-A2CC-1E6D18D14026");

 enum acer_wmi_event_ids {
 	WMID_HOTKEY_EVENT = 0x1,
+	WMID_ACCEL_EVENT = 0x5,
 };

 static const struct key_entry acer_wmi_keymap[] = {
@@ -130,6 +131,7 @@ static const struct key_entry acer_wmi_keymap[] = {
 };

 static struct input_dev *acer_wmi_input_dev;
+static struct input_dev *acer_wmi_accel_dev;

 struct event_return_value {
 	u8 function;
@@ -200,6 +202,7 @@ struct hotkey_function_type_aa {
 #define ACER_CAP_BLUETOOTH		(1<<2)
 #define ACER_CAP_BRIGHTNESS		(1<<3)
 #define ACER_CAP_THREEG			(1<<4)
+#define ACER_CAP_ACCEL			(1<<5)
 #define ACER_CAP_ANY			(0xFFFFFFFF)

 /*
@@ -1375,6 +1378,60 @@ static void acer_backlight_exit(void)
 }

 /*
+ * Accelerometer device
+ */
+static acpi_handle gsensor_handle;
+
+static int acer_gsensor_init(void)
+{
+	acpi_status status;
+	struct acpi_buffer output;
+	union acpi_object out_obj;
+
+	output.length = sizeof(out_obj);
+	output.pointer = &out_obj;
+	status = acpi_evaluate_object(gsensor_handle, "_INI", NULL, &output);
+	if (ACPI_FAILURE(status))
+		return -1;
+
+	return 0;
+}
+
+static int acer_gsensor_open(struct input_dev *input)
+{
+	return acer_gsensor_init();
+}
+
+static int acer_gsensor_event(void)
+{
+	acpi_status status;
+	struct acpi_buffer output;
+	union acpi_object out_obj[5];
+
+	if (!has_cap(ACER_CAP_ACCEL))
+		return -1;
+
+	output.length = sizeof(out_obj);
+	output.pointer = out_obj;
+
+	status = acpi_evaluate_object(gsensor_handle, "RDVL", NULL, &output);
+	if (ACPI_FAILURE(status))
+		return -1;
+
+	if (out_obj->package.count != 4)
+		return -1;
+
+	input_report_abs(acer_wmi_accel_dev, ABS_X,
+		(s16)out_obj->package.elements[0].integer.value);
+	input_report_abs(acer_wmi_accel_dev, ABS_Y,
+		(s16)out_obj->package.elements[1].integer.value);
+	input_report_abs(acer_wmi_accel_dev, ABS_Z,
+		(s16)out_obj->package.elements[2].integer.value);
+	input_sync(acer_wmi_accel_dev);
+	return 0;
+}
+
+/*
  * Rfkill devices
  */
 static void acer_rfkill_update(struct work_struct *ignored);
@@ -1649,6 +1706,9 @@ static void acer_wmi_notify(u32 value, void *context)
 						   1, true);
 		}
 		break;
+	case WMID_ACCEL_EVENT:
+		acer_gsensor_event();
+		break;
 	default:
 		pr_warn("Unknown function number - %d - %d\n",
 			return_value.function, return_value.key_num);
@@ -1734,6 +1794,74 @@ static int acer_wmi_enable_lm(void)
 	return status;
 }

+static acpi_status __init acer_wmi_get_handle_cb(acpi_handle ah, u32 level,
+						void *ctx, void **retval)
+{
+	*(acpi_handle *)retval = ah;
+	return AE_OK;
+}
+
+static int __init acer_wmi_get_handle(const char *name, const char *prop,
+					acpi_handle *ah)
+{
+	acpi_status status;
+	acpi_handle handle;
+
+	BUG_ON(!name || !ah);
+
+	handle = 0;
+	status = acpi_get_devices(prop, acer_wmi_get_handle_cb,
+					(void *)name, &handle);
+
+	if (ACPI_SUCCESS(status)) {
+		*ah = handle;
+		return 0;
+	} else {
+		return -ENODEV;
+	}
+}
+
+static int __init acer_wmi_accel_setup(void)
+{
+	int err;
+
+	err = acer_wmi_get_handle("SENR", "BST0001", &gsensor_handle);
+	if (err)
+		return err;
+
+	interface->capability |= ACER_CAP_ACCEL;
+
+	acer_wmi_accel_dev = input_allocate_device();
+	if (!acer_wmi_accel_dev)
+		return -ENOMEM;
+
+	acer_wmi_accel_dev->open = acer_gsensor_open;
+
+	acer_wmi_accel_dev->name = "Acer BMA150 accelerometer";
+	acer_wmi_accel_dev->phys = "wmi/input1";
+	acer_wmi_accel_dev->id.bustype = BUS_HOST;
+	acer_wmi_accel_dev->evbit[0] = BIT_MASK(EV_ABS);
+	input_set_abs_params(acer_wmi_accel_dev, ABS_X, -16384, 16384, 0, 0);
+	input_set_abs_params(acer_wmi_accel_dev, ABS_Y, -16384, 16384, 0, 0);
+	input_set_abs_params(acer_wmi_accel_dev, ABS_Z, -16384, 16384, 0, 0);
+
+	err = input_register_device(acer_wmi_accel_dev);
+	if (err)
+		goto err_free_dev;
+
+	return 0;
+
+err_free_dev:
+	input_free_device(acer_wmi_accel_dev);
+	return err;
+}
+
+static void acer_wmi_accel_destroy(void)
+{
+	input_unregister_device(acer_wmi_accel_dev);
+	input_free_device(acer_wmi_accel_dev);
+}
+
 static int __init acer_wmi_input_setup(void)
 {
 	acpi_status status;
@@ -1889,6 +2017,9 @@ static int acer_platform_resume(struct platform_device *device)
 	if (has_cap(ACER_CAP_BRIGHTNESS))
 		set_u32(data->brightness, ACER_CAP_BRIGHTNESS);

+	if (has_cap(ACER_CAP_ACCEL))
+		acer_gsensor_init();
+
 	return 0;
 }

@@ -2066,6 +2197,8 @@ static int __init acer_wmi_init(void)
 			return err;
 	}

+	acer_wmi_accel_setup();
+
 	err = platform_driver_register(&acer_platform_driver);
 	if (err) {
 		pr_err("Unable to register platform driver\n");
@@ -2109,6 +2242,8 @@ error_device_alloc:
 error_platform_register:
 	if (wmi_has_guid(ACERWMID_EVENT_GUID))
 		acer_wmi_input_destroy();
+	if (has_cap(ACER_CAP_ACCEL))
+		acer_wmi_accel_destroy();

 	return err;
 }
@@ -2118,6 +2253,9 @@ static void __exit acer_wmi_exit(void)
 	if (wmi_has_guid(ACERWMID_EVENT_GUID))
 		acer_wmi_input_destroy();

+	if (has_cap(ACER_CAP_ACCEL))
+		acer_wmi_accel_destroy();
+
 	remove_sysfs(acer_platform_device);
 	remove_debugfs();
 	platform_device_unregister(acer_platform_device);

[Padfoots]

shellscriptcoder, I will give that patch a try. May I ask where you found it? Is it proposed for the kernel?

Cheers.

[shellscriptcoder]

I located it at blog.gmane.org/gmane.linux.drivers.platform.x86.devel/3350 .

I'm not sure whether it's proposed for the kernel, but seeing as that is the driver dev page, there's a fair chance it will be implemented at some point.

[Padfoots]

shellscriptcoder, you are an absolute champion! Thank you so much.

I applied the patch and now have a working accelerometer on /dev/input/js*

Hopefully this will be included in the kernel soon. I have checked the source for 3.5.rc1 and it is not there yet, but here's hoping.

Thanks again.