diff options
author | Chris Ruehl <chris.ruehl@gtsys.com.hk> | 2020-05-11 11:30:21 +0300 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2020-05-15 20:50:05 +0300 |
commit | d065f41a3f0d0974593122e4864e158bb945696e (patch) | |
tree | 4e74dce9af6c785e58a55e3a2382952829f74234 /drivers | |
parent | d66571a20f68f153c045c9822bf4c288e7511168 (diff) | |
download | linux-d065f41a3f0d0974593122e4864e158bb945696e.tar.xz |
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: Chris Ruehl <chris.ruehl@gtsys.com.hk>
Link: https://lore.kernel.org/r/20200511083022.23678-3-chris.ruehl@gtsys.com.hk
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/spi/spi-rockchip.c | 44 |
1 files changed, 38 insertions, 6 deletions
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index c501d8a84414..f57a8faa6f31 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -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)) { |