[PATCH 04/10] usb: musb: ux500: harden checks for platform data

[sergei.shtylyov@cogentembedded.com (Sergei Shtylyov)]

Hello.

On 04/23/2013 07:03 PM, Lee Jones wrote:

> In its current state, the ux500-musb driver uses platform data pointers
> blindly with no prior checking. If no platform data pointer is passed
> this will Oops the kernel. In this patch we ensure platform data and
> board data are present prior to using them.
>
> Cc: Felipe Balbi <balbi@ti.com>
> Cc: linux-usb at vger.kernel.org
> Signed-off-by: Lee Jones <lee.jones@linaro.org>
> ---
>   drivers/usb/musb/ux500_dma.c |   11 ++++++++---
>   1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/musb/ux500_dma.c b/drivers/usb/musb/ux500_dma.c
> index c75e07a..02b4a6e 100644
> --- a/drivers/usb/musb/ux500_dma.c
> +++ b/drivers/usb/musb/ux500_dma.c
> @@ -287,7 +287,7 @@ static int ux500_dma_controller_start(struct dma_controller *c)
>   	struct musb *musb = controller->private_data;
>   	struct device *dev = musb->controller;
>   	struct musb_hdrc_platform_data *plat = dev->platform_data;
> -	struct ux500_musb_board_data *data = plat->board_data;
> +	struct ux500_musb_board_data *data;
>   	struct dma_channel *dma_channel = NULL;
>   	u32 ch_num;
>   	u8 dir;
> @@ -297,14 +297,19 @@ static int ux500_dma_controller_start(struct dma_controller *c)

[...]

>   
>   	/* Prepare the loop for RX channels */
>   	channel_array = controller->rx_channel;
> -	param_array = data->dma_rx_param_array;
> +	param_array = (data) ? data->dma_rx_param_array : NULL;

    Why enclose a simple variable in parens?

>   
>   	for (dir = 0; dir < 2; dir++) {
>   		for (ch_num = 0;
> @@ -337,7 +342,7 @@ static int ux500_dma_controller_start(struct dma_controller *c)
>   
>   		/* Prepare the loop for TX channels */
>   		channel_array = controller->tx_channel;
> -		param_array = data->dma_tx_param_array;
> +		param_array = (data) ? data->dma_tx_param_array : NULL;

    Again, why?

WBR, Sergei