[RFC PATCH v2 01/12] dmaengine: PL08x: Refactor pl08x_getbytes_chan() to lower indentation
Vinod Koul
vinod.koul at intel.com
Tue Jun 25 11:16:12 EDT 2013
On Sat, Jun 22, 2013 at 10:42:33PM +0200, Tomasz Figa wrote:
> Further patch will introduce support for PL080S, which requires some
> things to be done conditionally, thus increasing indentation level of
> some functions even more.
>
> This patch reduces indentation level of pl08x_getbytes_chan() function
> by inverting several conditions and returning from function wherever
> possible.
>
> Signed-off-by: Tomasz Figa <tomasz.figa at gmail.com>
> ---
> drivers/dma/amba-pl08x.c | 53 ++++++++++++++++++++++++++----------------------
> 1 file changed, 29 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
> index 06fe45c..6a12392 100644
> --- a/drivers/dma/amba-pl08x.c
> +++ b/drivers/dma/amba-pl08x.c
> @@ -469,47 +469,52 @@ static inline u32 get_bytes_in_cctl(u32 cctl)
> /* The channel should be paused when calling this */
> static u32 pl08x_getbytes_chan(struct pl08x_dma_chan *plchan)
> {
> + struct pl08x_lli *llis_va;
> struct pl08x_phy_chan *ch;
> + dma_addr_t llis_bus;
> struct pl08x_txd *txd;
> - size_t bytes = 0;
> + size_t bytes;
> + int index;
> + u32 clli;
>
> ch = plchan->phychan;
> txd = plchan->at;
>
> + if (!ch || !txd)
> + return 0;
shouldnt this be err return
> +
> /*
> * Follow the LLIs to get the number of remaining
> * bytes in the currently active transaction.
> */
> - if (ch && txd) {
> - u32 clli = readl(ch->base + PL080_CH_LLI) & ~PL080_LLI_LM_AHB2;
> + clli = readl(ch->base + PL080_CH_LLI) & ~PL080_LLI_LM_AHB2;
>
> - /* First get the remaining bytes in the active transfer */
> - bytes = get_bytes_in_cctl(readl(ch->base + PL080_CH_CONTROL));
> + /* First get the remaining bytes in the active transfer */
> + bytes = get_bytes_in_cctl(readl(ch->base + PL080_CH_CONTROL));
>
> - if (clli) {
> - struct pl08x_lli *llis_va = txd->llis_va;
> - dma_addr_t llis_bus = txd->llis_bus;
> - int index;
> + if (!clli)
> + return bytes;
>
> - BUG_ON(clli < llis_bus || clli >= llis_bus +
> + llis_va = txd->llis_va;
> + llis_bus = txd->llis_bus;
> +
> + BUG_ON(clli < llis_bus || clli >= llis_bus +
> sizeof(struct pl08x_lli) * MAX_NUM_TSFR_LLIS);
IMO BUG_ON is too much for this. Perhaps returning error and logging error would
be okay
--
~Vinod
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