[PATCH 5.4 049/110] HID: Add quirk for incorrect input length on Lenovo Y720

From: Greg Kroah-Hartman
Date: Thu Jan 30 2020 - 13:52:11 EST


From: Pavel Balan <admin@xxxxxxxxx>

[ Upstream commit fd0913768701612fc2b8ab9c8a5c019133e8d978 ]

Apply it to the Lenovo Y720 gaming laptop I2C peripheral then.

This fixes dmesg being flooded with errors visible on un-suspend
in Linux Mint 19 Cinnamon.

Example of error log:

<...>
[ 4.326588] i2c_hid i2c-ITE33D1:00: i2c_hid_get_input: incomplete report (2/4)
[ 4.326845] i2c_hid i2c-ITE33D1:00: i2c_hid_get_input: incomplete report (2/4)
[ 4.327095] i2c_hid i2c-ITE33D1:00: i2c_hid_get_input: incomplete report (2/4)
[ 4.327341] i2c_hid i2c-ITE33D1:00: i2c_hid_get_input: incomplete report (2/4)
[ 4.327609] i2c_hid i2c-ITE33D1:00: i2c_hid_get_input: incomplete report (2/4)
<...>

Example of fixed log (debug on)

<...>
[ 3731.333183] i2c_hid i2c-ITE33D1:00: input: 02 00
[ 3731.333581] i2c_hid i2c-ITE33D1:00: input: 02 00
[ 3731.333842] i2c_hid i2c-ITE33D1:00: input: 02 00
[ 3731.334107] i2c_hid i2c-ITE33D1:00: input: 02 00
[ 3731.334367] i2c_hid i2c-ITE33D1:00: input: 02 00
<...>

[jkosina@xxxxxxx: rebase onto more recent codebase]
Signed-off-by: Pavel Balan <admin@xxxxxxxxx>
Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/hid/hid-ids.h | 1 +
drivers/hid/i2c-hid/i2c-hid-core.c | 16 +++++++++++++---
2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 27795eac93e35..5fc82029a03b7 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -631,6 +631,7 @@
#define USB_VENDOR_ID_ITE 0x048d
#define USB_DEVICE_ID_ITE_LENOVO_YOGA 0x8386
#define USB_DEVICE_ID_ITE_LENOVO_YOGA2 0x8350
+#define I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720 0x837a
#define USB_DEVICE_ID_ITE_LENOVO_YOGA900 0x8396
#define USB_DEVICE_ID_ITE8595 0x8595

diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index ac44bf752ff1f..479934f7d2411 100644
--- a/drivers/hid/i2c-hid/i2c-hid-core.c
+++ b/drivers/hid/i2c-hid/i2c-hid-core.c
@@ -49,6 +49,8 @@
#define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET BIT(1)
#define I2C_HID_QUIRK_BOGUS_IRQ BIT(4)
#define I2C_HID_QUIRK_RESET_ON_RESUME BIT(5)
+#define I2C_HID_QUIRK_BAD_INPUT_SIZE BIT(6)
+

/* flags */
#define I2C_HID_STARTED 0
@@ -177,6 +179,8 @@ static const struct i2c_hid_quirks {
I2C_HID_QUIRK_BOGUS_IRQ },
{ USB_VENDOR_ID_ALPS_JP, HID_ANY_ID,
I2C_HID_QUIRK_RESET_ON_RESUME },
+ { USB_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720,
+ I2C_HID_QUIRK_BAD_INPUT_SIZE },
{ 0, 0 }
};

@@ -498,9 +502,15 @@ static void i2c_hid_get_input(struct i2c_hid *ihid)
}

if ((ret_size > size) || (ret_size < 2)) {
- dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
- __func__, size, ret_size);
- return;
+ if (ihid->quirks & I2C_HID_QUIRK_BAD_INPUT_SIZE) {
+ ihid->inbuf[0] = size & 0xff;
+ ihid->inbuf[1] = size >> 8;
+ ret_size = size;
+ } else {
+ dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
+ __func__, size, ret_size);
+ return;
+ }
}

i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
--
2.20.1