[PATCH] USB: serial: ch341: Add product ID for CH9102

[PATCH] USB: serial: ch341: Add product ID for CH9102

[Blake LaFleur]

Adds a PID for the CH9102 chipset that can be found in some cheap ESP
development boards.

Example: LILYGO T-Display (and its S3 variant)
https://lilygo.cc/products/lilygo%C2%AE-ttgo-t-display-1-14-inch-lcd-esp32-control-board

After patching the driver to include idProduct=0x55d4 the devices work
as expected.

Signed-off-by: Blake LaFleur <blake.k.lafleur@gmail.com>
---
 drivers/usb/serial/ch341.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index d10e4c4848a0..302d8d8547cb 100644
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -81,6 +81,7 @@
 #define CH341_QUIRK_SIMULATE_BREAK	BIT(1)
 
 static const struct usb_device_id id_table[] = {
+	{ USB_DEVICE(0x1a86, 0x55d4) },
 	{ USB_DEVICE(0x1a86, 0x5523) },
 	{ USB_DEVICE(0x1a86, 0x7522) },
 	{ USB_DEVICE(0x1a86, 0x7523) },
-- 
2.45.2

Re: [PATCH] USB: serial: ch341: Add product ID for CH9102

[Johan Hovold]

On Sun, Dec 08, 2024 at 02:11:15AM -0600, Blake LaFleur wrote:
> Adds a PID for the CH9102 chipset that can be found in some cheap ESP
> development boards.
> 
> Example: LILYGO T-Display (and its S3 variant)
> https://lilygo.cc/products/lilygo%C2%AE-ttgo-t-display-1-14-inch-lcd-esp32-control-board
> 
> After patching the driver to include idProduct=0x55d4 the devices work
> as expected.

Thanks for the patch. This is the first time I hear of CH9102.

Are there any errors or messages at all in the logs when you use this
device or does it appear to be perfectly compatible with the older
models?

Could you post the output of lsusb -v (with masked serial numbers if you
prefer) so we have a record of any type identifying information should
it ever be needed?
 
> Signed-off-by: Blake LaFleur <blake.k.lafleur@gmail.com>
> ---
>  drivers/usb/serial/ch341.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
> index d10e4c4848a0..302d8d8547cb 100644
> --- a/drivers/usb/serial/ch341.c
> +++ b/drivers/usb/serial/ch341.c
> @@ -81,6 +81,7 @@
>  #define CH341_QUIRK_SIMULATE_BREAK	BIT(1)
>  
>  static const struct usb_device_id id_table[] = {
> +	{ USB_DEVICE(0x1a86, 0x55d4) },

nit: please try to keep the entries sorted by pid.

>  	{ USB_DEVICE(0x1a86, 0x5523) },
>  	{ USB_DEVICE(0x1a86, 0x7522) },
>  	{ USB_DEVICE(0x1a86, 0x7523) },

Johan

Re: [PATCH] USB: serial: ch341: Add product ID for CH9102

[Johan Hovold]

On Wed, Dec 11, 2024 at 10:35:44AM +0100, Johan Hovold wrote:
> On Sun, Dec 08, 2024 at 02:11:15AM -0600, Blake LaFleur wrote:
> > Adds a PID for the CH9102 chipset that can be found in some cheap ESP
> > development boards.
> > 
> > Example: LILYGO T-Display (and its S3 variant)
> > https://lilygo.cc/products/lilygo%C2%AE-ttgo-t-display-1-14-inch-lcd-esp32-control-board
> > 
> > After patching the driver to include idProduct=0x55d4 the devices work
> > as expected.
> 
> Thanks for the patch. This is the first time I hear of CH9102.
> 
> Are there any errors or messages at all in the logs when you use this
> device or does it appear to be perfectly compatible with the older
> models?

For the record, Blake reported off list that this device is in fact a
CDC-ACM device.

There is a vendor driver here:

	https://github.com/WCHSoftGroup/ch343ser_linux

Johan