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Message-ID: <c13930a5-85ab-5a2c-54e5-15fc5bc87b17@canonical.com>
Date:   Wed, 2 Mar 2022 12:14:03 +0100
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Subject: Re: [PATCH] serial: samsung: Add samsung_early_read to support early
 kgdboc
Content-Language: en-US
To:     Woody Lin <woodylin@google.com>,
        Alim Akhtar <alim.akhtar@samsung.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        linux-samsung-soc@vger.kernel.org, linux-serial@vger.kernel.org,
        linux-kernel@vger.kernel.org, markcheng@google.com
References: <20220302101925.210810-1-woodylin@google.com>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
In-Reply-To: <20220302101925.210810-1-woodylin@google.com>
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Precedence: bulk

On 02/03/2022 11:19, Woody Lin wrote:
> The 'kgdboc_earlycon_init' looks for boot console that has both .read
> and .write callbacks. Adds 'samsung_early_read' to samsung_tty.c's early
> console to support kgdboc.
> 
> Signed-off-by: Woody Lin <woodylin@google.com>
> ---
>  drivers/tty/serial/samsung_tty.c | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
> index d002a4e48ed9..eeb30d016ff1 100644
> --- a/drivers/tty/serial/samsung_tty.c
> +++ b/drivers/tty/serial/samsung_tty.c
> @@ -2949,6 +2949,7 @@ static void wr_reg_barrier(struct uart_port *port, u32 reg, u32 val)
>  
>  struct samsung_early_console_data {
>  	u32 txfull_mask;
> +	u32 rxfifo_mask;
>  };
>  
>  static void samsung_early_busyuart(struct uart_port *port)
> @@ -2983,6 +2984,26 @@ static void samsung_early_write(struct console *con, const char *s,
>  	uart_console_write(&dev->port, s, n, samsung_early_putc);
>  }
>  
> +static int samsung_early_read(struct console *con, char *s, unsigned int n)
> +{
> +	struct earlycon_device *dev = con->data;
> +	struct samsung_early_console_data *data = dev->port.private_data;

This can be const.

Rest looks ok.


Best regards,
Krzysztof