[PATCH] Input: elantech - add LEN2146 to SMBus blacklist for ThinkPad L13 Gen2

ThinkPad L13 Gen2 has both touchpad and trackpoint.
PNP: LEN2146 PNP0f13
With the default protocol (elantech-smbus) trackpoint is not operating,
while touchpad does. Changing to elantech renders both operational.

Signed-off-by: Nikolai Kostrigin <redacted>
---
 drivers/input/mouse/elantech.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 90f8765f9efc..c4c3fa5828d8 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c

@@ -1776,6 +1776,7 @@ static const char * const i2c_blacklist_pnp_ids[] = {
 	 * These are known to not be working properly as bits are missing
 	 * in elan_i2c.
 	 */
+	"LEN2146", /* ThinkPad L13 Gen2 */
 	NULL
 };
 

-- 
2.29.2

Hi Nikolai,

On Mon, Feb 8, 2021 at 9:01 AM Nikolai Kostrigin [off-list ref] wrote:

ThinkPad L13 Gen2 has both touchpad and trackpoint.
PNP: LEN2146 PNP0f13
With the default protocol (elantech-smbus) trackpoint is not operating,
while touchpad does. Changing to elantech renders both operational.

Signed-off-by: Nikolai Kostrigin <redacted>

Instead of downgrading the capabilities of the touchpad, couldn't we
fix the trackpoint issues?

I am surprised elantech doesn't work with the trackpoint, because I am
pretty sure I wrote patches in that regard. Which kernel version have
you been testing?

Cheers,
Benjamin

Hi, Benjamin!

08.02.2021 11:06, Benjamin Tissoires пишет:

Hi Nikolai,

On Mon, Feb 8, 2021 at 9:01 AM Nikolai Kostrigin [off-list ref] wrote:

quoted

ThinkPad L13 Gen2 has both touchpad and trackpoint.
PNP: LEN2146 PNP0f13
With the default protocol (elantech-smbus) trackpoint is not operating,
while touchpad does. Changing to elantech renders both operational.

Signed-off-by: Nikolai Kostrigin <redacted>

Instead of downgrading the capabilities of the touchpad, couldn't we
fix the trackpoint issues?

Yes, I consider fixing the issue would be better than downgrading
touchpad capabilities.
Blacklisting was the first and most obvious idea to test.

I'm eager to perform additional diagnostics to choose a better solution.
Your advice would be appreciated.

I am surprised elantech doesn't work with the trackpoint, because I am
pretty sure I wrote patches in that regard. Which kernel version have
you been testing?

The patch was tested with 5.10.13 only, but the trackpoint behaviour is
the same on 5.4.92.

Cheers,
Benjamin

quoted

---
 drivers/input/mouse/elantech.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 90f8765f9efc..c4c3fa5828d8 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c

@@ -1776,6 +1776,7 @@ static const char * const i2c_blacklist_pnp_ids[] = {
         * These are known to not be working properly as bits are missing
         * in elan_i2c.
         */
+       "LEN2146", /* ThinkPad L13 Gen2 */
        NULL
 };

--

2.29.2

-- 
Best regards,
Nikolai Kostrigin