Re: [PATCH] tty: serial: imx: return error when clk_per fails in imx_uart_poll_init()

[Jiri Slaby <jirislaby@kernel.org>]

On 10. 11. 26, 11:54, Gu Bin wrote:
> In imx_uart_poll_init(), when clk_prepare_enable(sport->clk_per) fails
> the error branch only disables the previously enabled clk_ipg and then
> falls through: the function keeps programming the UART (imx_uart_setup_ufcr
> and the register writes below) with both clocks disabled and eventually
> returns 0, reporting success for a port that never came up.
> 
> The sibling imx_uart_startup() handles the same situation by returning
> the error after the rollback.
> 
> Return the error after rolling back clk_ipg, matching
> imx_uart_startup().
> 
> Fixes: 6b8bdad96164 ("serial: imx: add imx_poll_init()")
> Signed-off-by: Gu Bin <gubin@cmss.chinamobile.com>

I am not sure this is correct at all.

Ccin the author of the code would've helped. Done now.

> ---
>   drivers/tty/serial/imx.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
> index 0831bd5ee3dc..2a931361d17c 100644
> --- a/drivers/tty/serial/imx.c
> +++ b/drivers/tty/serial/imx.c
> @@ -1954,8 +1954,10 @@ static int imx_uart_poll_init(struct uart_port *port)
>   	if (retval)
>   		return retval;
>   	retval = clk_prepare_enable(sport->clk_per);
> -	if (retval)
> +	if (retval) {
>   		clk_disable_unprepare(sport->clk_ipg);
> +		return retval;
> +	}
>   
>   	imx_uart_setup_ufcr(sport, TXTL_DEFAULT, sport->rxtl);
>   


-- 
js
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