The patch dw: spi: add support for Amazon's Alpine spi controller has been applied to the spi tree at https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark >From f2d704794864a4bb486f2a0eaed40f25dd87303f Mon Sep 17 00:00:00 2001 From: Talel Shenhar <talel@xxxxxxxxxx> Date: Thu, 11 Oct 2018 14:20:07 +0300 Subject: [PATCH] dw: spi: add support for Amazon's Alpine spi controller Add support for a new devicetree compatible string called 'amazon,alpine-apb-ssi', which is necessary for the Amazon Alpine spi controller. 'amazon,alpine-dw-apb-ssi' is used in the dw spi driver if specified in the devicetree. Otherwise, fall back to driver default behavior, i.e. original dw IP hw driver behavior. Signed-off-by: Talel Shenhar <talel@xxxxxxxxxx> Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx> --- drivers/spi/spi-dw-mmio.c | 9 +++++++++ drivers/spi/spi-dw.c | 6 ++++++ drivers/spi/spi-dw.h | 2 ++ 3 files changed, 17 insertions(+) diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c index a768461614a0..3ffb6a40fe0c 100644 --- a/drivers/spi/spi-dw-mmio.c +++ b/drivers/spi/spi-dw-mmio.c @@ -126,6 +126,14 @@ static int dw_spi_mscc_jaguar2_init(struct platform_device *pdev, JAGUAR2_IF_SI_OWNER_OFFSET); } +static int dw_spi_alpine_init(struct platform_device *pdev, + struct dw_spi_mmio *dwsmmio) +{ + dwsmmio->dws.cs_override = 1; + + return 0; +} + static int dw_spi_mmio_probe(struct platform_device *pdev) { int (*init_func)(struct platform_device *pdev, @@ -230,6 +238,7 @@ static const struct of_device_id dw_spi_mmio_of_match[] = { { .compatible = "snps,dw-apb-ssi", }, { .compatible = "mscc,ocelot-spi", .data = dw_spi_mscc_ocelot_init}, { .compatible = "mscc,jaguar2-spi", .data = dw_spi_mscc_jaguar2_init}, + { .compatible = "amazon,alpine-dw-apb-ssi", .data = dw_spi_alpine_init}, { /* end of table */} }; MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match); diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c index 3e205ab60cd4..b705f2bdb8b9 100644 --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -144,6 +144,8 @@ void dw_spi_set_cs(struct spi_device *spi, bool enable) if (!enable) dw_writel(dws, DW_SPI_SER, BIT(spi->chip_select)); + else if (dws->cs_override) + dw_writel(dws, DW_SPI_SER, 0); } EXPORT_SYMBOL_GPL(dw_spi_set_cs); @@ -463,6 +465,10 @@ static void spi_hw_init(struct device *dev, struct dw_spi *dws) dws->fifo_len = (fifo == 1) ? 0 : fifo; dev_dbg(dev, "Detected FIFO size: %u bytes\n", dws->fifo_len); } + + /* enable HW fixup for explicit CS deselect for Amazon's alpine chip */ + if (dws->cs_override) + dw_writel(dws, DW_SPI_CS_OVERRIDE, 0xF); } int dw_spi_add_host(struct device *dev, struct dw_spi *dws) diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h index 0168b08364d5..c9c15881e982 100644 --- a/drivers/spi/spi-dw.h +++ b/drivers/spi/spi-dw.h @@ -32,6 +32,7 @@ #define DW_SPI_IDR 0x58 #define DW_SPI_VERSION 0x5c #define DW_SPI_DR 0x60 +#define DW_SPI_CS_OVERRIDE 0xf4 /* Bit fields in CTRLR0 */ #define SPI_DFS_OFFSET 0 @@ -109,6 +110,7 @@ struct dw_spi { u32 fifo_len; /* depth of the FIFO buffer */ u32 max_freq; /* max bus freq supported */ + int cs_override; u32 reg_io_width; /* DR I/O width in bytes */ u16 bus_num; u16 num_cs; /* supported slave numbers */ -- 2.19.0.rc2
