From 1475af255e18f35dc46f8a7acc18354c73d45149 Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng Date: Mon, 7 Jan 2019 15:24:29 +0800 Subject: [PATCH] HID: i2c-hid: Ignore input report if there's no data present on Elan touchpanels While using Elan touchpads, the message floods: [ 136.138487] i2c_hid i2c-DELL08D6:00: i2c_hid_get_input: incomplete report (14/65535) Though the message flood is annoying, the device it self works without any issue. I suspect that the device in question takes too much time to pull the IRQ back to high after I2C host has done reading its data. Since the host receives all useful data, let's ignore the input report when there's no data. Signed-off-by: Kai-Heng Feng Signed-off-by: Benjamin Tissoires --- drivers/hid/i2c-hid/i2c-hid-core.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c index 8555ce7..2f940c1 100644 --- a/drivers/hid/i2c-hid/i2c-hid-core.c +++ b/drivers/hid/i2c-hid/i2c-hid-core.c @@ -50,6 +50,7 @@ #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET BIT(1) #define I2C_HID_QUIRK_NO_RUNTIME_PM BIT(2) #define I2C_HID_QUIRK_DELAY_AFTER_SLEEP BIT(3) +#define I2C_HID_QUIRK_BOGUS_IRQ BIT(4) /* flags */ #define I2C_HID_STARTED 0 @@ -179,6 +180,8 @@ static const struct i2c_hid_quirks { I2C_HID_QUIRK_DELAY_AFTER_SLEEP }, { USB_VENDOR_ID_LG, I2C_DEVICE_ID_LG_8001, I2C_HID_QUIRK_NO_RUNTIME_PM }, + { USB_VENDOR_ID_ELAN, HID_ANY_ID, + I2C_HID_QUIRK_BOGUS_IRQ }, { 0, 0 } }; @@ -503,6 +506,12 @@ static void i2c_hid_get_input(struct i2c_hid *ihid) return; } + if (ihid->quirks & I2C_HID_QUIRK_BOGUS_IRQ && ret_size == 0xffff) { + dev_warn_once(&ihid->client->dev, "%s: IRQ triggered but " + "there's no data\n", __func__); + return; + } + if ((ret_size > size) || (ret_size < 2)) { dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n", __func__, size, ret_size); -- 2.7.4