diff options
author | Sascha Hauer <s.hauer@pengutronix.de> | 2019-05-21 09:06:41 +0200 |
---|---|---|
committer | Miquel Raynal <miquel.raynal@bootlin.com> | 2019-06-27 20:05:29 +0200 |
commit | e0ddaab76802d3179013f4864535043e2aea6c69 (patch) | |
tree | 992fba574f07acb858f55e728b3f566f8bde2ab1 | |
parent | 475345e89ced298afbeefed6c86122bb8415593d (diff) |
dmaengine: mxs: Add header file to be shared with gpmi nand driver
The mxs dma driver can do PIO transfers. A pointer to the PIO words
to transfer is passed in the struct scatterlist * argument of
dmaengine_prep_slave_sg(). It's quite ugly and non obvious to cast
u32 * to struct scatterlist * each time when calling
dmaengine_prep_slave_sg(), so add a static inline wrapper function
to be called by the user along with a description what is going on.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
-rw-r--r-- | drivers/dma/mxs-dma.c | 1 | ||||
-rw-r--r-- | drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 36 | ||||
-rw-r--r-- | include/linux/dma/mxs-dma.h | 21 |
3 files changed, 36 insertions, 22 deletions
diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c index ce92a3626ea4..62ee9328aea1 100644 --- a/drivers/dma/mxs-dma.c +++ b/drivers/dma/mxs-dma.c @@ -24,6 +24,7 @@ #include <linux/of_device.h> #include <linux/of_dma.h> #include <linux/list.h> +#include <linux/dma/mxs-dma.h> #include <asm/irq.h> diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c index 74c4de0b1a3d..45c7b91aae23 100644 --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c @@ -15,6 +15,7 @@ #include <linux/of.h> #include <linux/of_device.h> #include <linux/pm_runtime.h> +#include <linux/dma/mxs-dma.h> #include "gpmi-nand.h" #include "gpmi-regs.h" #include "bch-regs.h" @@ -914,9 +915,8 @@ static int gpmi_send_command(struct gpmi_nand_data *this) | BM_GPMI_CTRL0_ADDRESS_INCREMENT | BF_GPMI_CTRL0_XFER_COUNT(this->command_length); pio[1] = pio[2] = 0; - desc = dmaengine_prep_slave_sg(channel, - (struct scatterlist *)pio, - ARRAY_SIZE(pio), DMA_TRANS_NONE, 0); + desc = mxs_dmaengine_prep_pio(channel, pio, ARRAY_SIZE(pio), + DMA_TRANS_NONE, 0); if (!desc) return -EINVAL; @@ -988,8 +988,8 @@ static int gpmi_send_data(struct gpmi_nand_data *this, const void *buf, int len) | BF_GPMI_CTRL0_ADDRESS(address) | BF_GPMI_CTRL0_XFER_COUNT(len); pio[1] = 0; - desc = dmaengine_prep_slave_sg(channel, (struct scatterlist *)pio, - ARRAY_SIZE(pio), DMA_TRANS_NONE, 0); + desc = mxs_dmaengine_prep_pio(channel, pio, ARRAY_SIZE(pio), + DMA_TRANS_NONE, 0); if (!desc) return -EINVAL; @@ -1025,9 +1025,8 @@ static int gpmi_read_data(struct gpmi_nand_data *this, void *buf, int len) | BF_GPMI_CTRL0_ADDRESS(BV_GPMI_CTRL0_ADDRESS__NAND_DATA) | BF_GPMI_CTRL0_XFER_COUNT(len); pio[1] = 0; - desc = dmaengine_prep_slave_sg(channel, - (struct scatterlist *)pio, - ARRAY_SIZE(pio), DMA_TRANS_NONE, 0); + desc = mxs_dmaengine_prep_pio(channel, pio, ARRAY_SIZE(pio), + DMA_TRANS_NONE, 0); if (!desc) return -EINVAL; @@ -1083,10 +1082,8 @@ static int gpmi_send_page(struct gpmi_nand_data *this, dma_addr_t payload, pio[4] = payload; pio[5] = auxiliary; - desc = dmaengine_prep_slave_sg(channel, - (struct scatterlist *)pio, - ARRAY_SIZE(pio), DMA_TRANS_NONE, - DMA_CTRL_ACK); + desc = mxs_dmaengine_prep_pio(channel, pio, ARRAY_SIZE(pio), + DMA_TRANS_NONE, DMA_CTRL_ACK); if (!desc) return -EINVAL; @@ -1117,9 +1114,7 @@ static int gpmi_read_page(struct gpmi_nand_data *this, dma_addr_t payload, | BF_GPMI_CTRL0_ADDRESS(address) | BF_GPMI_CTRL0_XFER_COUNT(0); pio[1] = 0; - desc = dmaengine_prep_slave_sg(channel, - (struct scatterlist *)pio, 2, - DMA_TRANS_NONE, 0); + desc = mxs_dmaengine_prep_pio(channel, pio, 2, DMA_TRANS_NONE, 0); if (!desc) return -EINVAL; @@ -1144,10 +1139,8 @@ static int gpmi_read_page(struct gpmi_nand_data *this, dma_addr_t payload, pio[3] = geo->page_size; pio[4] = payload; pio[5] = auxiliary; - desc = dmaengine_prep_slave_sg(channel, - (struct scatterlist *)pio, - ARRAY_SIZE(pio), DMA_TRANS_NONE, - DMA_CTRL_ACK); + desc = mxs_dmaengine_prep_pio(channel, pio, ARRAY_SIZE(pio), + DMA_TRANS_NONE, DMA_CTRL_ACK); if (!desc) return -EINVAL; @@ -1163,9 +1156,8 @@ static int gpmi_read_page(struct gpmi_nand_data *this, dma_addr_t payload, | BF_GPMI_CTRL0_XFER_COUNT(geo->page_size); pio[1] = 0; pio[2] = 0; /* clear GPMI_HW_GPMI_ECCCTRL, disable the BCH. */ - desc = dmaengine_prep_slave_sg(channel, - (struct scatterlist *)pio, 3, - DMA_TRANS_NONE, DMA_CTRL_ACK); + desc = mxs_dmaengine_prep_pio(channel, pio, 3, DMA_TRANS_NONE, + DMA_CTRL_ACK); if (!desc) return -EINVAL; diff --git a/include/linux/dma/mxs-dma.h b/include/linux/dma/mxs-dma.h new file mode 100644 index 000000000000..092b2a7b92ac --- /dev/null +++ b/include/linux/dma/mxs-dma.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _MXS_DMA_H_ +#define _MXS_DMA_H_ + +#include <linux/dmaengine.h> + +/* + * The mxs dmaengine can do PIO transfers. We pass a pointer to the PIO words + * in the second argument to dmaengine_prep_slave_sg when the direction is + * set to DMA_TRANS_NONE. To make this clear and to prevent users from doing + * the error prone casting we have this wrapper function + */ +static inline struct dma_async_tx_descriptor *mxs_dmaengine_prep_pio( + struct dma_chan *chan, u32 *pio, unsigned int npio, + enum dma_transfer_direction dir, unsigned long flags) +{ + return dmaengine_prep_slave_sg(chan, (struct scatterlist *)pio, npio, + dir, flags); +} + +#endif /* _MXS_DMA_H_ */ |