Commit 9f14538e authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Mark Brown
Browse files

spi: dw-mid: split dma_setup() from dma_transfer() 



The patch splits DMA preparatory code to dma_setup() callback. The change also
converts transfer_one() to program DMA whenever the transfer is DMA mapped. The
change is a follow up of the converion to use SPI core transfer_one_message().
Since the DMA mapped transfers can be interleaved with PIO ones the DMA related
configuration should respect that.

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent e31abce7

drivers/spi/spi-dw-mid.c

+6 −11
Original line number Diff line number Diff line
@@ -207,12 +207,10 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws) 
	return rxdesc;

}



static void dw_spi_dma_setup(struct dw_spi *dws)

static int mid_spi_dma_setup(struct dw_spi *dws)

{

	u16 dma_ctrl = 0;



	spi_enable_chip(dws, 0);



	dw_writew(dws, DW_SPI_DMARDLR, 0xf);

	dw_writew(dws, DW_SPI_DMATDLR, 0x10);
@@ -222,21 +220,17 @@ static void dw_spi_dma_setup(struct dw_spi *dws) 
		dma_ctrl |= SPI_DMA_RDMAE;

	dw_writew(dws, DW_SPI_DMACR, dma_ctrl);



	spi_enable_chip(dws, 1);

	return 0;

}



static int mid_spi_dma_transfer(struct dw_spi *dws, int cs_change)

static int mid_spi_dma_transfer(struct dw_spi *dws)

{

	struct dma_async_tx_descriptor *txdesc, *rxdesc;



	/* 1. setup DMA related registers */

	if (cs_change)

		dw_spi_dma_setup(dws);



	/* 2. Prepare the TX dma transfer */

	/* Prepare the TX dma transfer */

	txdesc = dw_spi_dma_prepare_tx(dws);



	/* 3. Prepare the RX dma transfer */

	/* Prepare the RX dma transfer */

	rxdesc = dw_spi_dma_prepare_rx(dws);



	/* rx must be started before tx due to spi instinct */
@@ -258,6 +252,7 @@ static int mid_spi_dma_transfer(struct dw_spi *dws, int cs_change) 
static struct dw_spi_dma_ops mid_dma_ops = {

	.dma_init	= mid_spi_dma_init,

	.dma_exit	= mid_spi_dma_exit,

	.dma_setup	= mid_spi_dma_setup,

	.dma_transfer	= mid_spi_dma_transfer,

};

#endif

drivers/spi/spi-dw.c

+13 −10
Original line number Diff line number Diff line
@@ -316,11 +316,11 @@ static int dw_spi_transfer_one(struct spi_master *master, 
	struct dw_spi *dws = spi_master_get_devdata(master);

	struct chip_data *chip = spi_get_ctldata(spi);

	u8 imask = 0;

	u8 cs_change = 0;

	u16 txlevel = 0;

	u16 clk_div = 0;

	u32 speed = 0;

	u32 cr0 = 0;

	int ret;



	dws->n_bytes = chip->n_bytes;

	dws->dma_width = chip->dma_width;
@@ -332,8 +332,6 @@ static int dw_spi_transfer_one(struct spi_master *master, 
	dws->rx = transfer->rx_buf;

	dws->rx_end = dws->rx + transfer->len;

	dws->len = transfer->len;

	if (chip != dws->prev_chip)

		cs_change = 1;



	spi_enable_chip(dws, 0);
@@ -397,7 +395,13 @@ static int dw_spi_transfer_one(struct spi_master *master, 
	 * Interrupt mode

	 * we only need set the TXEI IRQ, as TX/RX always happen syncronizely

	 */

	if (!dws->dma_mapped && !chip->poll_mode) {

	if (dws->dma_mapped) {

		ret = dws->dma_ops->dma_setup(dws);

		if (ret < 0) {

			spi_enable_chip(dws, 1);

			return ret;

		}

	} else if (!chip->poll_mode) {

		txlevel = min_t(u16, dws->fifo_len / 2, dws->len / dws->n_bytes);

		dw_writew(dws, DW_SPI_TXFLTR, txlevel);
@@ -411,11 +415,11 @@ static int dw_spi_transfer_one(struct spi_master *master, 


	spi_enable_chip(dws, 1);



	if (cs_change)

		dws->prev_chip = chip;



	if (dws->dma_mapped)

		dws->dma_ops->dma_transfer(dws, cs_change);

	if (dws->dma_mapped) {

		ret = dws->dma_ops->dma_transfer(dws);

		if (ret < 0)

			return ret;

	}



	if (chip->poll_mode)

		return poll_transfer(dws);
@@ -546,7 +550,6 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) 


	dws->master = master;

	dws->type = SSI_MOTO_SPI;

	dws->prev_chip = NULL;

	dws->dma_inited = 0;

	dws->dma_addr = (dma_addr_t)(dws->paddr + 0x60);

	snprintf(dws->name, sizeof(dws->name), "dw_spi%d", dws->bus_num);

drivers/spi/spi-dw.h

+2 −2
Original line number Diff line number Diff line
@@ -91,7 +91,8 @@ struct dw_spi; 
struct dw_spi_dma_ops {

	int (*dma_init)(struct dw_spi *dws);

	void (*dma_exit)(struct dw_spi *dws);

	int (*dma_transfer)(struct dw_spi *dws, int cs_change);

	int (*dma_setup)(struct dw_spi *dws);

	int (*dma_transfer)(struct dw_spi *dws);

};



struct dw_spi {
@@ -109,7 +110,6 @@ struct dw_spi { 
	u16			num_cs;		/* supported slave numbers */



	/* Current message transfer state info */

	struct chip_data	*prev_chip;

	size_t			len;

	void			*tx;

	void			*tx_end;

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