Re: [PATCH] mmc: omap_hsmmc: Initialize dma_slave_config to avoid random data

From: Peter Ujfalusi
Date: Wed Sep 14 2016 - 06:59:46 EST


On 09/14/16 13:23, Arnd Bergmann wrote:
> On Wednesday, September 14, 2016 1:10:48 PM CEST Peter Ujfalusi wrote:
>> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
>> index 24ebc9a8de89..0a5640156159 100644
>> --- a/drivers/mmc/host/omap_hsmmc.c
>> +++ b/drivers/mmc/host/omap_hsmmc.c
>> @@ -1409,7 +1409,7 @@ static int omap_hsmmc_pre_dma_transfer(struct omap_hsmmc_host *host,
>> static int omap_hsmmc_setup_dma_transfer(struct omap_hsmmc_host *host,
>> struct mmc_request *req)
>> {
>> - struct dma_slave_config cfg;
>> + struct dma_slave_config cfg = {};
>> struct dma_async_tx_descriptor *tx;
>> int ret = 0, i;
>> struct mmc_data *data = req->data;
>>
>
> This change looks correct and is certainly the simplest solution if you want to
> get it into v4.8, but generally speaking, I think it would be nicer to combine
> it with the initialization of the fields:
>
> struct dma_slave_config cfg = {
> .src_addr = host->mapbase + OMAP_HSMMC_DATA;
> .dst_addr = host->mapbase + OMAP_HSMMC_DATA;
> .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
> .dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
> .src_maxburst = data->blksz / 4;
> .dst_maxburst = data->blksz / 4;

I opted to not do this because the data->blksz is validated later in the
function (twice).

It is not a big issue, but looks a bit odd.

--
Péter