Re: [PATCH v3 1/1] i2c: imx: refactor error handling on i2c_imx_dma_request()

["Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>]

On Fri, Nov 30, 2018 at 10:44:18AM +0100, Oleksij Rempel wrote:
> From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> 
> Current implementation will print error if system is not configured
> with DMA for I2C core. At least on i.MX5x variants is DMA event for I2C
> muxed with SDHC. So it is project specific configuration and not an error.
> 
> This patch will also affect probe, since it will forward all error except
> of missing DMA.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> [ore: make it actually compile, fix a corner case]
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> ---
> changes:
> 20181130 v3:
>  - reword commit message 
> 20181112 v2:
>  - drop "[PATCH v1 2/3] i2c: imx: probe dma only only on i.MX50 and
>    later" and rebase without this patch.
>  - Set proper initial author
> 
>  drivers/i2c/busses/i2c-imx.c | 36 +++++++++++++++++++++---------------
>  1 file changed, 21 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> index c406700789e1..3c12b174bbb1 100644
> --- a/drivers/i2c/busses/i2c-imx.c
> +++ b/drivers/i2c/busses/i2c-imx.c
> @@ -273,7 +273,7 @@ static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx,
>  }
>  
>  /* Functions for DMA support */
> -static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
> +static int i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
>  						dma_addr_t phy_addr)

If you touch the line above, maybe also realign the followup line to
start at the opening parenthesis.

>  {
>  	struct imx_i2c_dma *dma;
> @@ -283,11 +283,13 @@ static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx,
>  
>  	dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
>  	if (!dma)
> -		return;
> +		return -ENOMEM;
>  
> -	dma->chan_tx = dma_request_slave_channel(dev, "tx");
> +	dma->chan_tx = dma_request_chan(dev, "tx");

Maybe this is worth a separate change?

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
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