Re: [RFC PATCH v3 1/5] mmc: dw_mmc: Add external dma interface support
From: Heiko Stübner <heiko@sntech.de>
Date: 2015-08-05 08:49:26
Also in:
linux-mips, linux-mmc, linux-rockchip, linux-samsung-soc
Am Mittwoch, 5. August 2015, 16:17:28 schrieb Shawn Lin:
DesignWare MMC Controller can supports two types of DMA mode: external dma and internal dma. We get a RK312x platform integrated dw_mmc and ARM pl330 dma controller. This patch add edmac ops to support these platforms. I've tested it on RK312x platform with edmac mode and RK3288 platform with idmac mode. Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> ---
[...]
quoted hunk ↗ jump to hunk
diff --git a/include/linux/mmc/dw_mmc.h b/include/linux/mmc/dw_mmc.h index 5be9767..6c1c7ea 100644 --- a/include/linux/mmc/dw_mmc.h +++ b/include/linux/mmc/dw_mmc.h@@ -16,6 +16,7 @@ #include <linux/scatterlist.h> #include <linux/mmc/core.h> +#include <linux/dmaengine.h> #define MAX_MCI_SLOTS 2@@ -40,6 +41,17 @@ enum { struct mmc_data; +enum { + TRANS_MODE_PIO = 0, + TRANS_MODE_IDMAC, + TRANS_MODE_EDMAC +}; + +struct dw_mci_dma_slave { + struct dma_chan *ch; + enum dma_transfer_direction direction; +}; + /** * struct dw_mci - MMC controller state shared between all slots * @lock: Spinlock protecting the queue and associated data.@@ -147,17 +159,23 @@ struct dw_mci { /* DMA interface members*/ int use_dma; + int trans_mode;
you're introducing this new trans_mode, but we have "use_dma" already.
So you could just define
enum {
TRANS_DMA_PIO = 0,
TRANS_DMA_IDMAC,
TRANS_DMA_EDMAC
};
and fill use_dma appropriately. "0" is meaning PIO already, which I also did fix
up some days ago in "[PATCH] mmc: dw_mmc: fix pio mode when internal dmac is
enabled" [0].
Heiko
[0] https://lkml.org/lkml/2015/8/3/407