diff options
| author | Chanho Park <chanho61.park@samsung.com> | 2022-06-29 19:23:01 +0900 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2022-06-29 12:37:06 +0100 |
| commit | ffb7bcd3b27e86fa7bdbabf4488060064ec9d00d (patch) | |
| tree | 50850f41d493549e42e8c1ad891f0b71c7a67fb7 /drivers/spi | |
| parent | 152f2494ac16d17c111cf982d2ad75c6a82d9da8 (diff) | |
spi: s3c64xx: support loopback mode
Modern exynos SoCs can support self loopback mode via setting BIT(3) of
MODE_CFG register. Previous SoCs don't have the bit so we need to add
has_loopback field in the s3c64xx_spi_port_config. Exynos Auto v9 SoC
has the bit and it will define the field to "true".
When it is set, SPI_LOOP mode will be marked.
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Andi Shyti <andi@etezian.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Link: https://lore.kernel.org/r/20220629102304.65712-2-chanho61.park@samsung.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-s3c64xx.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c index 302c1d4a28b1..0c917cf891ca 100644 --- a/drivers/spi/spi-s3c64xx.c +++ b/drivers/spi/spi-s3c64xx.c @@ -59,6 +59,7 @@ #define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD (1<<17) #define S3C64XX_SPI_MODE_BUS_TSZ_WORD (2<<17) #define S3C64XX_SPI_MODE_BUS_TSZ_MASK (3<<17) +#define S3C64XX_SPI_MODE_SELF_LOOPBACK (1<<3) #define S3C64XX_SPI_MODE_RXDMA_ON (1<<2) #define S3C64XX_SPI_MODE_TXDMA_ON (1<<1) #define S3C64XX_SPI_MODE_4BURST (1<<0) @@ -135,6 +136,7 @@ struct s3c64xx_spi_dma_data { * @clk_from_cmu: True, if the controller does not include a clock mux and * prescaler unit. * @clk_ioclk: True if clock is present on this device + * @has_loopback: True if loopback mode can be supported * * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but * differ in some aspects such as the size of the fifo and spi bus clock @@ -149,6 +151,7 @@ struct s3c64xx_spi_port_config { bool high_speed; bool clk_from_cmu; bool clk_ioclk; + bool has_loopback; }; /** @@ -659,6 +662,9 @@ static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd) break; } + if ((sdd->cur_mode & SPI_LOOP) && sdd->port_conf->has_loopback) + val |= S3C64XX_SPI_MODE_SELF_LOOPBACK; + writel(val, regs + S3C64XX_SPI_MODE_CFG); if (sdd->port_conf->clk_from_cmu) { @@ -1148,6 +1154,8 @@ static int s3c64xx_spi_probe(struct platform_device *pdev) SPI_BPW_MASK(8); /* the spi->mode bits understood by this driver: */ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + if (sdd->port_conf->has_loopback) + master->mode_bits |= SPI_LOOP; master->auto_runtime_pm = true; if (!is_polling(sdd)) master->can_dma = s3c64xx_spi_can_dma; |