Unverified Commit d065f41a authored by Chris Ruehl's avatar Chris Ruehl Committed by Mark Brown
Browse files

spi: spi-rockchip: add support for spi slave mode 



Add support for spi slave mode in spi-rockchip. The register map has an entry
for it. If spi-slave is set in dts, set this corresponding bit and add to
mode_bits the SPI_NO_CS, allow slave mode without explicit CS use.
Slave abort function had been added.

Signed-off-by: default avatarChris Ruehl <chris.ruehl@gtsys.com.hk>
Link: https://lore.kernel.org/r/20200511083022.23678-3-chris.ruehl@gtsys.com.hk


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent d66571a2

drivers/spi/spi-rockchip.c

+38 −6
Original line number Diff line number Diff line
@@ -183,6 +183,8 @@ struct rockchip_spi { 
	u8 rsd;



	bool cs_asserted[ROCKCHIP_SPI_MAX_CS_NUM];



	bool slave_abort;

};



static inline void spi_enable_chip(struct rockchip_spi *rs, bool enable)
@@ -359,7 +361,7 @@ static void rockchip_spi_dma_rxcb(void *data) 
	struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);

	int state = atomic_fetch_andnot(RXDMA, &rs->state);



	if (state & TXDMA)

	if (state & TXDMA && !rs->slave_abort)

		return;



	spi_enable_chip(rs, false);
@@ -372,7 +374,7 @@ static void rockchip_spi_dma_txcb(void *data) 
	struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);

	int state = atomic_fetch_andnot(TXDMA, &rs->state);



	if (state & RXDMA)

	if (state & RXDMA && !rs->slave_abort)

		return;



	/* Wait until the FIFO data completely. */
@@ -457,7 +459,7 @@ static int rockchip_spi_prepare_dma(struct rockchip_spi *rs, 


static void rockchip_spi_config(struct rockchip_spi *rs,

		struct spi_device *spi, struct spi_transfer *xfer,

		bool use_dma)

		bool use_dma, bool slave_mode)

{

	u32 cr0 = CR0_FRF_SPI  << CR0_FRF_OFFSET

	        | CR0_BHT_8BIT << CR0_BHT_OFFSET
@@ -466,6 +468,10 @@ static void rockchip_spi_config(struct rockchip_spi *rs, 
	u32 cr1;

	u32 dmacr = 0;



	if (slave_mode)

		cr0 |= CR0_OPM_SLAVE << CR0_OPM_OFFSET;

	rs->slave_abort = false;



	cr0 |= rs->rsd << CR0_RSD_OFFSET;

	cr0 |= (spi->mode & 0x3U) << CR0_SCPH_OFFSET;

	if (spi->mode & SPI_LSB_FIRST)
@@ -535,6 +541,16 @@ static size_t rockchip_spi_max_transfer_size(struct spi_device *spi) 
	return ROCKCHIP_SPI_MAX_TRANLEN;

}



static int rockchip_spi_slave_abort(struct spi_controller *ctlr)

{

	struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);



	rs->slave_abort = true;

	complete(&ctlr->xfer_completion);



	return 0;

}



static int rockchip_spi_transfer_one(

		struct spi_controller *ctlr,

		struct spi_device *spi,
@@ -560,7 +576,7 @@ static int rockchip_spi_transfer_one( 


	use_dma = ctlr->can_dma ? ctlr->can_dma(ctlr, spi, xfer) : false;



	rockchip_spi_config(rs, spi, xfer, use_dma);

	rockchip_spi_config(rs, spi, xfer, use_dma, ctlr->slave);



	if (use_dma)

		return rockchip_spi_prepare_dma(rs, ctlr, xfer);
@@ -588,15 +604,26 @@ static int rockchip_spi_probe(struct platform_device *pdev) 
	struct rockchip_spi *rs;

	struct spi_controller *ctlr;

	struct resource *mem;

	struct device_node *np = pdev->dev.of_node;

	u32 rsd_nsecs;

	bool slave_mode;



	slave_mode = of_property_read_bool(np, "spi-slave");



	if (slave_mode)

		ctlr = spi_alloc_slave(&pdev->dev,

				sizeof(struct rockchip_spi));

	else

		ctlr = spi_alloc_master(&pdev->dev,

				sizeof(struct rockchip_spi));



	ctlr = spi_alloc_master(&pdev->dev, sizeof(struct rockchip_spi));

	if (!ctlr)

		return -ENOMEM;



	platform_set_drvdata(pdev, ctlr);



	rs = spi_controller_get_devdata(ctlr);

	ctlr->slave = slave_mode;



	/* Get basic io resource and map it */

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -676,6 +703,12 @@ static int rockchip_spi_probe(struct platform_device *pdev) 
	ctlr->auto_runtime_pm = true;

	ctlr->bus_num = pdev->id;

	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP | SPI_LSB_FIRST;

	if (slave_mode) {

		ctlr->mode_bits |= SPI_NO_CS;

		ctlr->slave_abort = rockchip_spi_slave_abort;

	} else {

		ctlr->flags = SPI_MASTER_GPIO_SS;

	}

	ctlr->num_chipselect = ROCKCHIP_SPI_MAX_CS_NUM;

	ctlr->dev.of_node = pdev->dev.of_node;

	ctlr->bits_per_word_mask = SPI_BPW_MASK(16) | SPI_BPW_MASK(8) | SPI_BPW_MASK(4);
@@ -686,7 +719,6 @@ static int rockchip_spi_probe(struct platform_device *pdev) 
	ctlr->transfer_one = rockchip_spi_transfer_one;

	ctlr->max_transfer_size = rockchip_spi_max_transfer_size;

	ctlr->handle_err = rockchip_spi_handle_err;

	ctlr->flags = SPI_MASTER_GPIO_SS;



	ctlr->dma_tx = dma_request_chan(rs->dev, "tx");

	if (IS_ERR(ctlr->dma_tx)) {

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