RFC: Input: edt-ft5x06 - FT6336G Touch Panel

[Oliver Graute <oliver.graute@gmail.com>]

Hello,

I have on of these FT6336G Touch Panels here and I try to get it work
with the ft6236 driver. It comes up with model identification "0x11". So
I added that identification to the switch case in
edt_ft5x06_ts_identify(). But it crashes directly after the probe with a
corrupted stack. No clue why. Some ideas?

Best regards,

Oliver


@@ -879,6 +879,7 @@ static int edt_ft5x06_ts_identify(struct i2c_client *client,
 		 * the identification registers.
 		 */
 		switch (rdbuf[0]) {
+		case 0x11:   /* EDT EP0110M09 */
 		case 0x35:   /* EDT EP0350M09 */
 		case 0x43:   /* EDT EP0430M09 */
 		case 0x50:   /* EDT EP0500M09 */

In my device tree I added the following:

&i2c2 {
	#address-cells = <1>;
	#size-cells = <0>;
	clock-frequency = <100000>;
	pinctrl-names = "default";
	pinctrl-0 = <&pinctrl_lpi2c2>;
	status = "okay";

	polytouch: edt_ft6236@38 {
		compatible = "focaltech,ft6236";
		reg = <0x38>;
		pinctrl-names = "default";
		pinctrl-0 = <&pinctrl_edt_ft5x06>;
		interrupt-parent = <&lsio_gpio0>;
		interrupts = <2 0>;
	};
};

[    2.232596] i2c i2c-0: LPI2C adapter registered
[    2.238931] edt_ft5x06 1-0038: probing for EDT FT5x06 I2C
[    2.244369] edt_ft5x06 1-0038: 1-0038 supply vcc not found, using dummy regulator
[    2.257639] edt_ft5x06 1-0038: Model "EP0110M09", Rev. "�", 0x0 sensors
[    2.264536] input: EP0110M09 as /devices/platform/bus@5a000000/5a820000.i2c/i2c-1/1-0038/input/input0
[    2.273920] edt_ft5x06 1-0038: EDT FT5x06 initialized: IRQ 35, WAKE pin -1, Reset pin -1.
[    2.282124] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: edt_ft5x06_ts_probe+0x9d4/0xa88
[    2.292830] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.6.0-rc1-next-20200214-00051-g9874f196742d #69
[    2.302224] Hardware name: Advantech iMX8QM DMSSE20 (DT)
[    2.307544] Workqueue: events deferred_probe_work_func
[    2.312686] Call trace:
[    2.315141]  dump_backtrace+0x0/0x1c0
[    2.318802]  show_stack+0x14/0x20
[    2.322124]  dump_stack+0xb4/0xfc
[    2.325440]  panic+0x158/0x320
[    2.328494]  print_tainted+0x0/0xa8
[    2.331978]  edt_ft5x06_ts_probe+0x9d4/0xa88
[    2.336248]  i2c_device_probe+0x2d0/0x2f8
[    2.340258]  really_probe+0xd8/0x438
[    2.343836]  driver_probe_device+0xdc/0x130
[    2.348017]  __device_attach_driver+0x88/0x108
[    2.352464]  bus_for_each_drv+0x74/0xc0
[    2.356302]  __device_attach+0xdc/0x160
[    2.360133]  device_initial_probe+0x10/0x18
[    2.364312]  bus_probe_device+0x90/0x98
[    2.368151]  device_add+0x434/0x770
[    2.371636]  device_register+0x1c/0x28
[    2.375383]  i2c_new_client_device+0x134/0x2a8
[    2.379833]  of_i2c_register_device+0xb0/0xd8
[    2.384192]  of_i2c_register_devices+0x9c/0x198
[    2.388724]  i2c_register_adapter+0x150/0x418
[    2.393076]  __i2c_add_numbered_adapter+0x58/0xa0
[    2.397776]  i2c_add_adapter+0x9c/0xc8
[    2.401525]  lpi2c_imx_probe+0x1b0/0x2a0
[    2.405451]  platform_drv_probe+0x50/0xa0
[    2.409461]  really_probe+0xd8/0x438
[    2.413032]  driver_probe_device+0xdc/0x130
[    2.417210]  __device_attach_driver+0x88/0x108
[    2.421658]  bus_for_each_drv+0x74/0xc0
[    2.425489]  __device_attach+0xdc/0x160
[    2.429321]  device_initial_probe+0x10/0x18
[    2.433499]  bus_probe_device+0x90/0x98
[    2.437331]  deferred_probe_work_func+0x88/0xd8
[    2.441864]  process_one_work+0x19c/0x320
[    2.445870]  worker_thread+0x1f0/0x420
[    2.449622]  kthread+0xf0/0x120
[    2.452762]  ret_from_fork+0x10/0x18
[    2.456349] SMP: stopping secondary CPUs
[    2.460272] Kernel Offset: disabled
[    2.463762] CPU features: 0x00002,2000200c
[    2.467859] Memory Limit: none
[    2.470927] ---[ end Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: edt_ft5x06_ts_probe+0x9d4/0xa88 ]---