linux-kernel - Re: [PATCH v2] serial: atmel: convert not to use dma_request_slave

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <ccfcf2a5-c04b-4781-8658-d63044b9b9c6@tuxon.dev>
Date:   Mon, 20 Nov 2023 08:14:30 +0200
From:   claudiu beznea <claudiu.beznea@...on.dev>
To:     Christophe JAILLET <christophe.jaillet@...adoo.fr>,
        Richard Genoud <richard.genoud@...il.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Jiri Slaby <jirislaby@...nel.org>,
        Nicolas Ferre <nicolas.ferre@...rochip.com>,
        Alexandre Belloni <alexandre.belloni@...tlin.com>
Cc:     linux-kernel@...r.kernel.org, kernel-janitors@...r.kernel.org,
        linux-serial@...r.kernel.org, linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH v2] serial: atmel: convert not to use
 dma_request_slave_channel()

Hi, Christophe,

On 19.11.2023 17:55, Christophe JAILLET wrote:
> dma_request_slave_channel() is deprecated. dma_request_chan() should
> be used directly instead.
> 
> Switch to the preferred function and update the error handling accordingly.
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@...adoo.fr>
> ---
> v2: Also update atmel_prepare_rx_dma()
> ---
>  drivers/tty/serial/atmel_serial.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> index 1946fafc3f3e..6aeb4648843b 100644
> --- a/drivers/tty/serial/atmel_serial.c
> +++ b/drivers/tty/serial/atmel_serial.c
> @@ -1013,14 +1013,18 @@ static int atmel_prepare_tx_dma(struct uart_port *port)
>  	struct device *mfd_dev = port->dev->parent;
>  	dma_cap_mask_t		mask;
>  	struct dma_slave_config config;
> +	struct dma_chan *chan;

There is no need for this.

>  	int ret, nent;
>  
>  	dma_cap_zero(mask);
>  	dma_cap_set(DMA_SLAVE, mask);
>  
> -	atmel_port->chan_tx = dma_request_slave_channel(mfd_dev, "tx");
> -	if (atmel_port->chan_tx == NULL)
> +	chan = dma_request_chan(mfd_dev, "tx");
> +	if (IS_ERR(chan)) {
> +		atmel_port->chan_tx = NULL;
>  		goto chan_err;
> +	}
> +	atmel_port->chan_tx = chan;
>  	dev_info(port->dev, "using %s for tx DMA transfers\n",
>  		dma_chan_name(atmel_port->chan_tx));
>  
> @@ -1188,6 +1192,7 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
>  	dma_cap_mask_t		mask;
>  	struct dma_slave_config config;
>  	struct circ_buf		*ring;
> +	struct dma_chan *chan;

Ditto

>  	int ret, nent;
>  
>  	ring = &atmel_port->rx_ring;
> @@ -1195,9 +1200,12 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
>  	dma_cap_zero(mask);
>  	dma_cap_set(DMA_CYCLIC, mask);
>  
> -	atmel_port->chan_rx = dma_request_slave_channel(mfd_dev, "rx");
> -	if (atmel_port->chan_rx == NULL)
> +	chan = dma_request_chan(mfd_dev, "rx");
> +	if (IS_ERR(chan)) {
> +		atmel_port->chan_rx = NULL;
>  		goto chan_err;
> +	}
> +	atmel_port->chan_rx = chan;
>  	dev_info(port->dev, "using %s for rx DMA transfers\n",
>  		dma_chan_name(atmel_port->chan_rx));
>