Re: [PATCH v2 07/14] USB: ch341: add support for parity, frame length, stop bits

[One Thousand Gnomes]

On Sat,  2 Apr 2016 19:07:16 +0200
Grigori Goronzy <greg@xxxxxxxxxxxx> wrote:

> With the new reinitialization method, configuring parity, different
> frame lengths and different stop bit settings work as expected on
> both CH340G and CH341A.  This has been extensively tested with a
> logic analyzer.
> 
> Tested-by: Ryan Barber <rfb@xxxxxxxxxxxxx>
> Signed-off-by: Grigori Goronzy <greg@xxxxxxxxxxxx>
> ---
>  drivers/usb/serial/ch341.c | 36 ++++++++++++++++++++++++++++++------
>  1 file changed, 30 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
> index c001773..4d66f0f 100644
> --- a/drivers/usb/serial/ch341.c
> +++ b/drivers/usb/serial/ch341.c
> @@ -346,6 +346,7 @@ static void ch341_set_termios(struct tty_struct *tty,
>  	unsigned baud_rate;
>  	unsigned long flags;
>  	unsigned char ctrl;
> +	unsigned cflag = tty->termios.c_cflag;
>  	int r;
>  
>  	/* redundant changes may cause the chip to lose bytes */
> @@ -356,7 +357,35 @@ static void ch341_set_termios(struct tty_struct *tty,
>  
>  	priv->baud_rate = baud_rate;
>  
> -	ctrl = CH341_LCR_ENABLE_RX | CH341_LCR_ENABLE_TX | CH341_LCR_CS8;
> +	ctrl = CH341_LCR_ENABLE_RX | CH341_LCR_ENABLE_TX;
> +
> +	switch (cflag & CSIZE) {
> +	case CS5:
> +		ctrl |= CH341_LCR_CS5;
> +		break;
> +	case CS6:
> +		ctrl |= CH341_LCR_CS6;
> +		break;
> +	case CS7:
> +		ctrl |= CH341_LCR_CS7;
> +		break;
> +	case CS8:
> +	default:
> +		ctrl |= CH341_LCR_CS8;

In the default case tty-.termios.c_cflag should also be updated to show
CS8

Alan