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author | Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> | 2014-12-19 08:15:53 (GMT) |
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committer | Mark Brown <broonie@kernel.org> | 2014-12-24 12:31:17 (GMT) |
commit | 3110628d89f80fbafa085fd62e75afcb39fb764c (patch) | |
tree | ebab30303fbc275e5ab4f7dbb5d49e829435bdd1 | |
parent | 97bf6af1f928216fd6c5a66e8a57bfa95a659672 (diff) | |
download | linux-3110628d89f80fbafa085fd62e75afcb39fb764c.tar.xz |
spi: sh-msiof: Configure MSIOF sync signal timing in device tree
The MSIOF controller has DTDL and SYNCDL in SITMDR1 register. So,
this patch adds new properties like the following commit:
d0fb47a5237d8b9576113568bacfd27892308b62
(spi: fsl-espi: Configure FSL eSPI CSBEF and CSAFT)
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
-rw-r--r-- | Documentation/devicetree/bindings/spi/sh-msiof.txt | 16 | ||||
-rw-r--r-- | drivers/spi/spi-sh-msiof.c | 47 | ||||
-rw-r--r-- | include/linux/spi/sh_msiof.h | 2 |
3 files changed, 65 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/spi/sh-msiof.txt b/Documentation/devicetree/bindings/spi/sh-msiof.txt index d11c372..4c388bb 100644 --- a/Documentation/devicetree/bindings/spi/sh-msiof.txt +++ b/Documentation/devicetree/bindings/spi/sh-msiof.txt @@ -30,6 +30,22 @@ Optional properties: specifiers, one for transmission, and one for reception. - dma-names : Must contain a list of two DMA names, "tx" and "rx". +- renesas,dtdl : delay sync signal (setup) in transmit mode. + Must contain one of the following values: + 0 (no bit delay) + 50 (0.5-clock-cycle delay) + 100 (1-clock-cycle delay) + 150 (1.5-clock-cycle delay) + 200 (2-clock-cycle delay) + +- renesas,syncdl : delay sync signal (hold) in transmit mode. + Must contain one of the following values: + 0 (no bit delay) + 50 (0.5-clock-cycle delay) + 100 (1-clock-cycle delay) + 150 (1.5-clock-cycle delay) + 200 (2-clock-cycle delay) + 300 (3-clock-cycle delay) Optional properties, deprecated for soctype-specific bindings: - renesas,tx-fifo-size : Overrides the default tx fifo size given in words diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c index 239be7c..2a87cb9 100644 --- a/drivers/spi/spi-sh-msiof.c +++ b/drivers/spi/spi-sh-msiof.c @@ -82,6 +82,8 @@ struct sh_msiof_spi_priv { #define MDR1_SYNCMD_LR 0x30000000 /* L/R mode */ #define MDR1_SYNCAC_SHIFT 25 /* Sync Polarity (1 = Active-low) */ #define MDR1_BITLSB_SHIFT 24 /* MSB/LSB First (1 = LSB first) */ +#define MDR1_DTDL_SHIFT 20 /* Data Pin Bit Delay for MSIOF_SYNC */ +#define MDR1_SYNCDL_SHIFT 16 /* Frame Sync Signal Timing Delay */ #define MDR1_FLD_MASK 0x000000c0 /* Frame Sync Signal Interval (0-3) */ #define MDR1_FLD_SHIFT 2 #define MDR1_XXSTP 0x00000001 /* Transmission/Reception Stop on FIFO */ @@ -279,6 +281,48 @@ static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p, sh_msiof_write(p, RSCR, sh_msiof_spi_clk_table[k].scr); } +static u32 sh_msiof_get_delay_bit(u32 dtdl_or_syncdl) +{ + /* + * DTDL/SYNCDL bit : p->info->dtdl or p->info->syncdl + * b'000 : 0 + * b'001 : 100 + * b'010 : 200 + * b'011 (SYNCDL only) : 300 + * b'101 : 50 + * b'110 : 150 + */ + if (dtdl_or_syncdl % 100) + return dtdl_or_syncdl / 100 + 5; + else + return dtdl_or_syncdl / 100; +} + +static u32 sh_msiof_spi_get_dtdl_and_syncdl(struct sh_msiof_spi_priv *p) +{ + u32 val; + + if (!p->info) + return 0; + + /* check if DTDL and SYNCDL is allowed value */ + if (p->info->dtdl > 200 || p->info->syncdl > 300) { + dev_warn(&p->pdev->dev, "DTDL or SYNCDL is too large\n"); + return 0; + } + + /* check if the sum of DTDL and SYNCDL becomes an integer value */ + if ((p->info->dtdl + p->info->syncdl) % 100) { + dev_warn(&p->pdev->dev, "the sum of DTDL/SYNCDL is not good\n"); + return 0; + } + + val = sh_msiof_get_delay_bit(p->info->dtdl) << MDR1_DTDL_SHIFT; + val |= sh_msiof_get_delay_bit(p->info->syncdl) << MDR1_SYNCDL_SHIFT; + + return val; +} + static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p, u32 cpol, u32 cpha, u32 tx_hi_z, u32 lsb_first, u32 cs_high) @@ -296,6 +340,7 @@ static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p, tmp = MDR1_SYNCMD_SPI | 1 << MDR1_FLD_SHIFT | MDR1_XXSTP; tmp |= !cs_high << MDR1_SYNCAC_SHIFT; tmp |= lsb_first << MDR1_BITLSB_SHIFT; + tmp |= sh_msiof_spi_get_dtdl_and_syncdl(p); sh_msiof_write(p, TMDR1, tmp | MDR1_TRMD | TMDR1_PCON); if (p->chipdata->master_flags & SPI_MASTER_MUST_TX) { /* These bits are reserved if RX needs TX */ @@ -952,6 +997,8 @@ static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev) &info->tx_fifo_override); of_property_read_u32(np, "renesas,rx-fifo-size", &info->rx_fifo_override); + of_property_read_u32(np, "renesas,dtdl", &info->dtdl); + of_property_read_u32(np, "renesas,syncdl", &info->syncdl); info->num_chipselect = num_cs; diff --git a/include/linux/spi/sh_msiof.h b/include/linux/spi/sh_msiof.h index 88a14d8..b087a85 100644 --- a/include/linux/spi/sh_msiof.h +++ b/include/linux/spi/sh_msiof.h @@ -7,6 +7,8 @@ struct sh_msiof_spi_info { u16 num_chipselect; unsigned int dma_tx_id; unsigned int dma_rx_id; + u32 dtdl; + u32 syncdl; }; #endif /* __SPI_SH_MSIOF_H__ */ |