This patch fixes an issue where the touchpad cursor movement becomes
slow on the Dell Precision 5560. Force the touchpad freq to 100khz
as a workaround.

Tested on Dell Precision 5560 with 6.14 to 6.14.6. Cursor movement
is now smooth and responsive.

Changes in v1:
	- No code changes from first commit.

Signed-off-by: fangzhong.zhou <myth5@myth5.com>
---
 drivers/i2c/i2c-core-acpi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index d2499f302..5b424637b 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -371,6 +371,7 @@ static const struct acpi_device_id i2c_acpi_force_100khz_device_ids[] = {
 	 * a 400KHz frequency. The root cause of the issue is not known.
 	 */
 	{ "ELAN06FA", 0 },
+	{ "DLL0945", 0 },
 	{}
 };
 
-- 
2.48.1

On Sun, Aug 03, 2025 at 07:15:54AM +0800, fangzhong.zhou wrote:
> This patch fixes an issue where the touchpad cursor movement becomes
> slow on the Dell Precision 5560. Force the touchpad freq to 100khz
> as a workaround.
> 
> Tested on Dell Precision 5560 with 6.14 to 6.14.6. Cursor movement
> is now smooth and responsive.
> 
> Changes in v1:
> 	- No code changes from first commit.

The "Changes" section should go below "---". I fixed it.

> 
> Signed-off-by: fangzhong.zhou <myth5@myth5.com>
> ---
>  drivers/i2c/i2c-core-acpi.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
> index d2499f302..5b424637b 100644
> --- a/drivers/i2c/i2c-core-acpi.c
> +++ b/drivers/i2c/i2c-core-acpi.c
> @@ -371,6 +371,7 @@ static const struct acpi_device_id i2c_acpi_force_100khz_device_ids[] = {
>  	 * a 400KHz frequency. The root cause of the issue is not known.
>  	 */
>  	{ "ELAN06FA", 0 },
> +	{ "DLL0945", 0 },

I moved it up to keep alphabetical sorting.

With these changes:

Applied to for-next (for 6.17 mergewindow), thanks!