[U-Boot] [PATCH v2 1/2] spi: mxs: Introduce spi_cs_is_valid()

Introduce spi_cs_is_valid() for validating spi bus and chip select numbers.
Signed-off-by: Fabio Estevam fabio.estevam@freescale.com --- Changes since v1: - Newly introduced in v2
drivers/spi/mxs_spi.c | 13 +++++++++++-- 1 files changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c index 4e6f14e..e7237e7 100644 --- a/drivers/spi/mxs_spi.c +++ b/drivers/spi/mxs_spi.c @@ -51,14 +51,23 @@ void spi_init(void) { }
+int spi_cs_is_valid(unsigned int bus, unsigned int cs) +{ + /* MXS SPI: 4 ports and 3 chip selects maximum */ + if (bus > 3 || cs > 2) + return 0; + else + return 1; +} + struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, unsigned int max_hz, unsigned int mode) { struct mxs_spi_slave *mxs_slave; uint32_t addr;
- if (bus > 3) { - printf("MXS SPI: Max bus number is 3\n"); + if (!spi_cs_is_valid(bus, cs)) { + printf("mxs_spi: invalid bus %d / chip select %d\n", bus, cs); return NULL; }

MXS SSP controller may have up to three chip selects per port: SS0, SS1 and SS2.
Currently only SS0 is supported in the mxs_spi driver.
Allow all the three chip select to work by selecting the desired one in bits 20 and 21 of the HW_SSP_CTRL0 register.
Signed-off-by: Fabio Estevam fabio.estevam@freescale.com --- Changes since v1: - Check vor valid cs inside spi_cs_is_valid() (patch 1/2)
drivers/spi/mxs_spi.c | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c index e7237e7..7859536 100644 --- a/drivers/spi/mxs_spi.c +++ b/drivers/spi/mxs_spi.c @@ -34,6 +34,8 @@
#define MXS_SPI_MAX_TIMEOUT 1000000 #define MXS_SPI_PORT_OFFSET 0x2000 +#define MXS_SSP_CHIPSELECT_MASK 0x00300000 +#define MXS_SSP_CHIPSELECT_SHIFT 20
struct mxs_spi_slave { struct spi_slave slave; @@ -65,6 +67,8 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, { struct mxs_spi_slave *mxs_slave; uint32_t addr; + struct mx28_ssp_regs *ssp_regs; + int reg;
if (!spi_cs_is_valid(bus, cs)) { printf("mxs_spi: invalid bus %d / chip select %d\n", bus, cs); @@ -82,7 +86,13 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, mxs_slave->max_khz = max_hz / 1000; mxs_slave->mode = mode; mxs_slave->regs = (struct mx28_ssp_regs *)addr; + ssp_regs = mxs_slave->regs;
+ reg = readl(&ssp_regs->hw_ssp_ctrl0); + reg &= ~(MXS_SSP_CHIPSELECT_MASK); + reg |= cs << MXS_SSP_CHIPSELECT_SHIFT; + + writel(reg, &ssp_regs->hw_ssp_ctrl0); return &mxs_slave->slave; }

Dear Fabio Estevam,
MXS SSP controller may have up to three chip selects per port: SS0, SS1 and SS2.
Currently only SS0 is supported in the mxs_spi driver.
Allow all the three chip select to work by selecting the desired one in bits 20 and 21 of the HW_SSP_CTRL0 register.
Signed-off-by: Fabio Estevam fabio.estevam@freescale.com
Acked-by: Marek Vasut marex@denx.de
Changes since v1:
- Check vor valid cs inside spi_cs_is_valid() (patch 1/2)
drivers/spi/mxs_spi.c | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c index e7237e7..7859536 100644 --- a/drivers/spi/mxs_spi.c +++ b/drivers/spi/mxs_spi.c @@ -34,6 +34,8 @@
#define MXS_SPI_MAX_TIMEOUT 1000000 #define MXS_SPI_PORT_OFFSET 0x2000 +#define MXS_SSP_CHIPSELECT_MASK 0x00300000 +#define MXS_SSP_CHIPSELECT_SHIFT 20
struct mxs_spi_slave { struct spi_slave slave; @@ -65,6 +67,8 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, { struct mxs_spi_slave *mxs_slave; uint32_t addr;
struct mx28_ssp_regs *ssp_regs;
int reg;
if (!spi_cs_is_valid(bus, cs)) { printf("mxs_spi: invalid bus %d / chip select %d\n", bus, cs);
@@ -82,7 +86,13 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, mxs_slave->max_khz = max_hz / 1000; mxs_slave->mode = mode; mxs_slave->regs = (struct mx28_ssp_regs *)addr;
ssp_regs = mxs_slave->regs;
reg = readl(&ssp_regs->hw_ssp_ctrl0);
reg &= ~(MXS_SSP_CHIPSELECT_MASK);
reg |= cs << MXS_SSP_CHIPSELECT_SHIFT;
writel(reg, &ssp_regs->hw_ssp_ctrl0); return &mxs_slave->slave;
}
Best regards, Marek Vasut

On 23/04/2012 20:30, Fabio Estevam wrote:
MXS SSP controller may have up to three chip selects per port: SS0, SS1 and SS2.
Currently only SS0 is supported in the mxs_spi driver.
Allow all the three chip select to work by selecting the desired one in bits 20 and 21 of the HW_SSP_CTRL0 register.
Signed-off-by: Fabio Estevam fabio.estevam@freescale.com
Applied to u-boot-imx, thanks.
Best regards, Stefano Babic

Dear Fabio Estevam,
Introduce spi_cs_is_valid() for validating spi bus and chip select numbers.
Signed-off-by: Fabio Estevam fabio.estevam@freescale.com
Acked-by: Marek Vasut marex@denx.de
Changes since v1:
- Newly introduced in v2
drivers/spi/mxs_spi.c | 13 +++++++++++-- 1 files changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c index 4e6f14e..e7237e7 100644 --- a/drivers/spi/mxs_spi.c +++ b/drivers/spi/mxs_spi.c @@ -51,14 +51,23 @@ void spi_init(void) { }
+int spi_cs_is_valid(unsigned int bus, unsigned int cs) +{
- /* MXS SPI: 4 ports and 3 chip selects maximum */
- if (bus > 3 || cs > 2)
return 0;
- else
return 1;
+}
struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, unsigned int max_hz, unsigned int mode) { struct mxs_spi_slave *mxs_slave; uint32_t addr;
- if (bus > 3) {
printf("MXS SPI: Max bus number is 3\n");
- if (!spi_cs_is_valid(bus, cs)) {
return NULL; }printf("mxs_spi: invalid bus %d / chip select %d\n", bus, cs);
Best regards, Marek Vasut

On Monday 23 April 2012 14:30:49 Fabio Estevam wrote:
Introduce spi_cs_is_valid() for validating spi bus and chip select numbers.
Acked-by: Mike Frysinger vapier@gentoo.org -mike

On 23/04/2012 20:30, Fabio Estevam wrote:
Introduce spi_cs_is_valid() for validating spi bus and chip select numbers.
Signed-off-by: Fabio Estevam fabio.estevam@freescale.com
Applied to u-boot-imx, thanks.
Best regards, Stefano Babic
participants (4)
-
Fabio Estevam
-
Marek Vasut
-
Mike Frysinger
-
Stefano Babic