Re: [PATCH] HID: i2c-hid: Add no-irq-after-reset quirk for 0911:5288 device

Several cheap Apollo Lake based laptops / 2-in-1s use an i2c-hid mt
touchpad which is advertised by the DSDT with an ACPI HID of "SYNA3602",
this touchpad can be found on e.g. the Cube Thinker and the EZBook 3 Pro.

On my "T-bao Tbook air" the i2c-hid driver fails to bind to this touchpad:
"i2c_hid i2c-SYNA3602:00: failed to reset device.".

After some debuging this it seems that this touchpad simply never sends
an interrupt after a reset as expected by the i2c hid driver. This commit
adds a quirk for this device, making i2c_hid_command sleep 100ms after
a reset instead of waiting for an irq, fixing i2c-hid failing to bind to
this touchpad.

Signed-off-by: Hans de Goede <redacted>
---
 drivers/hid/hid-ids.h         | 7 +++++++
 drivers/hid/i2c-hid/i2c-hid.c | 7 ++++++-
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index be2e005c3c51..47c5e709c2fd 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h

@@ -1003,6 +1003,13 @@
 #define USB_DEVICE_ID_SYNAPTICS_QUAD_HD	0x1ac3
 #define USB_DEVICE_ID_SYNAPTICS_TP_V103	0x5710
 
+/*
+ * These are from i2c-hid mt touchpads found in several cheap Apollo Lake
+ * based laptops which advertise the touchpad with an ACPI HID of "SYNA3602".
+ */
+#define I2C_VENDOR_ID_SYNAPTICS		0x0911

+#define I2C_PRODUCT_ID_SYNA3602		0x5288
+
 #define USB_VENDOR_ID_TEXAS_INSTRUMENTS	0x2047
 #define USB_DEVICE_ID_TEXAS_INSTRUMENTS_LENOVO_YOGA	0x0855
 

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 7f701772edfe..9ceef884a4b3 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c

@@ -46,6 +46,7 @@
 
 /* quirks to control the device */
 #define I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV	BIT(0)
+#define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET	BIT(1)
 
 /* flags */
 #define I2C_HID_STARTED		0

@@ -168,6 +169,8 @@ static const struct i2c_hid_quirks {
 		I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
 	{ USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8755,
 		I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
+	{ I2C_VENDOR_ID_SYNAPTICS, I2C_PRODUCT_ID_SYNA3602,
+		I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
 	{ 0, 0 }
 };
 

@@ -252,7 +255,9 @@ static int __i2c_hid_command(struct i2c_client *client,
 
 	ret = 0;
 
-	if (wait) {
+	if (wait && (ihid->quirks & I2C_HID_QUIRK_NO_IRQ_AFTER_RESET)) {
+		msleep(100);