diff options
| author | Hung-Te Lin <hungte@chromium.org> | 2013-06-23 08:14:30 +0800 |
|---|---|---|
| committer | Stefan Reinauer <stefan.reinauer@coreboot.org> | 2013-07-10 23:14:49 +0200 |
| commit | e42030d23600990e95db2af1e9e1a366ff3d4ec7 (patch) | |
| tree | 4ee819c17a7ffc6ce9c648431e2518bb81d69629 /src/cpu/samsung/exynos5420/spi.c | |
| parent | 8b95c134207de9573f8e5eb758e5cee51741604a (diff) | |
arm/exynos: Correct SPI session commands.
Some initialization / shutdown commands should be paired correctly in a SPI I/O
session. For example, setting CS should be enabled and disabled in each read;
and the bus width (byte or word) should be configured only when opening /
closing the SPI device.
Change-Id: Ie56b1c3a6df7d542f7ea8f1193ac435987f937ba
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Reviewed-on: http://review.coreboot.org/3706
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src/cpu/samsung/exynos5420/spi.c')
| -rw-r--r-- | src/cpu/samsung/exynos5420/spi.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/src/cpu/samsung/exynos5420/spi.c b/src/cpu/samsung/exynos5420/spi.c index 503cee90ee..642ae23bb6 100644 --- a/src/cpu/samsung/exynos5420/spi.c +++ b/src/cpu/samsung/exynos5420/spi.c @@ -102,7 +102,6 @@ int exynos_spi_open(struct exynos_spi *regs) /* now set rx and tx channel ON */ setbits_le32(®s->ch_cfg, SPI_RX_CH_ON | SPI_TX_CH_ON | SPI_CH_HS_EN); - clrbits_le32(®s->cs_reg, SPI_SLAVE_SIG_INACT); /* CS low */ return 0; } @@ -110,6 +109,8 @@ int exynos_spi_read(struct exynos_spi *regs, void *dest, u32 len, u32 off) { int upto, todo; int i; + clrbits_le32(®s->cs_reg, SPI_SLAVE_SIG_INACT); /* CS low */ + /* Send read instruction (0x3h) followed by a 24 bit addr */ writel((SF_READ_DATA_CMD << 24) | off, ®s->tx_data); @@ -123,6 +124,11 @@ int exynos_spi_read(struct exynos_spi *regs, void *dest, u32 len, u32 off) setbits_le32(®s->cs_reg, SPI_SLAVE_SIG_INACT);/* make the CS high */ + return len; +} + +int exynos_spi_close(struct exynos_spi *regs) +{ /* * Let put controller mode to BYTE as * SPI driver does not support WORD mode yet @@ -131,11 +137,6 @@ int exynos_spi_read(struct exynos_spi *regs, void *dest, u32 len, u32 off) SPI_MODE_CH_WIDTH_WORD | SPI_MODE_BUS_WIDTH_WORD); writel(0, ®s->swap_cfg); - return len; -} - -int exynos_spi_close(struct exynos_spi *regs) -{ /* * Flush spi tx, rx fifos and reset the SPI controller * and clear rx/tx channel |