HID: i2c-hid: Ignore input report if there's no data present on Elan touchpanels

[mirror_ubuntu-bionic-kernel.git] / drivers / hid / i2c-hid / i2c-hid.c

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index b235d2b38f39590884b9896410ffbbc523b49001..95d6e1c1d97695d9a20b5856eb606873e78c858d 100644 (file)
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -49,6 +49,7 @@
 #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET       BIT(1)
 #define I2C_HID_QUIRK_RESEND_REPORT_DESCR      BIT(2)
 #define I2C_HID_QUIRK_NO_RUNTIME_PM            BIT(3)
+#define I2C_HID_QUIRK_BOGUS_IRQ                        BIT(4)
 
 /* flags */
 #define I2C_HID_STARTED                0
@@ -180,6 +181,8 @@ static const struct i2c_hid_quirks {
                I2C_HID_QUIRK_NO_RUNTIME_PM },
        { I2C_VENDOR_ID_GOODIX, I2C_DEVICE_ID_GOODIX_01F0,
                I2C_HID_QUIRK_NO_RUNTIME_PM },
+       { USB_VENDOR_ID_ELAN, HID_ANY_ID,
+                I2C_HID_QUIRK_BOGUS_IRQ },
        { 0, 0 }
 };
 
@@ -490,6 +493,12 @@ 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);