Re: [PATCH v2 5/7] USB: serial: xr: add support for XR21B1411

[Johan Hovold <johan@kernel.org>]

On Wed, Mar 24, 2021 at 08:41:09AM +0100, Mauro Carvalho Chehab wrote:
> There's nothing special on this device: it has just one port.
> 
> The only difference is that it uses a different register set.

Not quite true. First, it uses 12-bit registers, which the driver isn't
updated for. Similarly, it used 12-bit register *addresses* which
likewise the driver isn't updated for and the upper bits are simply
discarded.

This device also doesn't support CS5 and CS6 which would need to be
handled.

> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> ---
>  drivers/usb/serial/xr_serial.c | 30 ++++++++++++++++++++++++++++++
>  1 file changed, 30 insertions(+)
> 
> diff --git a/drivers/usb/serial/xr_serial.c b/drivers/usb/serial/xr_serial.c
> index 058624d15505..b1044dd3e994 100644
> --- a/drivers/usb/serial/xr_serial.c
> +++ b/drivers/usb/serial/xr_serial.c
> @@ -99,6 +99,7 @@ struct xr_txrx_clk_mask {
>  #define VIA_CDC_REGISTER		-1
>  
>  enum xr_model {
> +	XR21B1411,
>  	XR21V141X,
>  	XR21B142X,
>  	MAX_XR_MODELS
> @@ -132,6 +133,30 @@ enum xr_hal_type {
>  };
>  
>  static const int xr_hal_table[MAX_XR_MODELS][MAX_XR_HAL_TYPE] = {
> +	[XR21B1411] = {
> +		[REG_ENABLE] =				0xc00,
> +		[REG_FORMAT] =				VIA_CDC_REGISTER,
> +		[REG_FLOW_CTRL] =			0xc06,
> +		[REG_XON_CHAR] =			0xc07,
> +		[REG_XOFF_CHAR] =			0xc08,
> +		[REG_TX_BREAK] =			0xc0a,
> +		[REG_RS485_DELAY] =			0xc0b,
> +		[REG_GPIO_MODE] =			0xc0c,
> +		[REG_GPIO_DIR] =			0xc0d,
> +		[REG_GPIO_SET] =			0xc0e,
> +		[REG_GPIO_CLR] =			0xc0f,
> +		[REG_GPIO_STATUS] =			0xc10,
> +		[REG_GPIO_INT_MASK] =			0xc11,
> +		[REG_CUSTOMIZED_INT] =			0xc12,
> +		[REG_GPIO_PULL_UP_ENABLE] =		0xc14,
> +		[REG_GPIO_PULL_DOWN_ENABLE] =		0xc15,
> +		[REG_LOOPBACK] =			0xc16,
> +		[REG_LOW_LATENCY] =			0xcc2,
> +		[REG_CUSTOM_DRIVER] =			0x20d,
> +
> +		[REQ_SET] =				0,
> +		[REQ_GET] =				1,
> +	},
>  	[XR21V141X] = {
>  		[REG_ENABLE] =				0x03,
>  		[REG_FORMAT] =				0x0b,

Johan