diff options
| author | Geert Uytterhoeven <geert+renesas@glider.be> | 2017-12-13 20:05:11 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2017-12-14 12:46:07 +0100 |
| commit | 9cce882bedd2768dc251b73f2ad86a9bfcfd9fc7 (patch) | |
| tree | 4cad033f301cd7628aea3ba08923b6f8e1500232 /drivers/spi | |
| parent | spi: sh-msiof: Avoid writing to registers from spi_master.setup() (diff) | |
| download | linux-9cce882bedd2768dc251b73f2ad86a9bfcfd9fc7.tar.xz linux-9cce882bedd2768dc251b73f2ad86a9bfcfd9fc7.zip | |
spi: sh-msiof: Extend support to 3 native chip selects
Currently only the MSIOF_SYNC signal can be used as a native chip
select. Extend support to up to 3 native chipselects using the
MSIOF_SS1 and MSIOF_SS2 signals.
Inspired by a patch in the BSP by Hiromitsu Yamasaki.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-sh-msiof.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c index 2704abb11ea4..9bdc292aa050 100644 --- a/drivers/spi/spi-sh-msiof.c +++ b/drivers/spi/spi-sh-msiof.c @@ -60,6 +60,8 @@ struct sh_msiof_spi_priv { bool slave_aborted; }; +#define MAX_SS 3 /* Maximum number of native chip selects */ + #define TMDR1 0x00 /* Transmit Mode Register 1 */ #define TMDR2 0x04 /* Transmit Mode Register 2 */ #define TMDR3 0x08 /* Transmit Mode Register 3 */ @@ -93,6 +95,8 @@ struct sh_msiof_spi_priv { #define MDR1_XXSTP 0x00000001 /* Transmission/Reception Stop on FIFO */ /* TMDR1 */ #define TMDR1_PCON 0x40000000 /* Transfer Signal Connection */ +#define TMDR1_SYNCCH_MASK 0xc000000 /* Synchronization Signal Channel Select */ +#define TMDR1_SYNCCH_SHIFT 26 /* 0=MSIOF_SYNC, 1=MSIOF_SS1, 2=MSIOF_SS2 */ /* TMDR2 and RMDR2 */ #define MDR2_BITLEN1(i) (((i) - 1) << 24) /* Data Size (8-32 bits) */ @@ -326,7 +330,7 @@ static u32 sh_msiof_spi_get_dtdl_and_syncdl(struct sh_msiof_spi_priv *p) return val; } -static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p, +static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p, u32 ss, u32 cpol, u32 cpha, u32 tx_hi_z, u32 lsb_first, u32 cs_high) { @@ -344,10 +348,13 @@ static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p, tmp |= !cs_high << MDR1_SYNCAC_SHIFT; tmp |= lsb_first << MDR1_BITLSB_SHIFT; tmp |= sh_msiof_spi_get_dtdl_and_syncdl(p); - if (spi_controller_is_slave(p->master)) + if (spi_controller_is_slave(p->master)) { sh_msiof_write(p, TMDR1, tmp | TMDR1_PCON); - else - sh_msiof_write(p, TMDR1, tmp | MDR1_TRMD | TMDR1_PCON); + } else { + sh_msiof_write(p, TMDR1, + tmp | MDR1_TRMD | TMDR1_PCON | + (ss < MAX_SS ? ss : 0) << TMDR1_SYNCCH_SHIFT); + } if (p->master->flags & SPI_MASTER_MUST_TX) { /* These bits are reserved if RX needs TX */ tmp &= ~0x0000ffff; @@ -575,7 +582,8 @@ static int sh_msiof_prepare_message(struct spi_master *master, const struct spi_device *spi = msg->spi; /* Configure pins before asserting CS */ - sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL), + sh_msiof_spi_set_pin_regs(p, spi->chip_select, + !!(spi->mode & SPI_CPOL), !!(spi->mode & SPI_CPHA), !!(spi->mode & SPI_3WIRE), !!(spi->mode & SPI_LSB_FIRST), |