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author | Uwe Kleine-König <u.kleine-koenig@pengutronix.de> | 2010-09-09 21:02:48 +0200 |
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committer | Sascha Hauer <s.hauer@pengutronix.de> | 2010-10-01 09:32:13 +0200 |
commit | 0b599603d8534bc3946a0f07e461c76d7947dfcf (patch) | |
tree | 18d5b7a0279f54f2f939b1399aca5f443cbc431f /drivers/spi | |
parent | 3b2aa89eb381d2f445aa3c60d8f070a3f55efa63 (diff) | |
download | kernel_goldelico_gta04-0b599603d8534bc3946a0f07e461c76d7947dfcf.zip kernel_goldelico_gta04-0b599603d8534bc3946a0f07e461c76d7947dfcf.tar.gz kernel_goldelico_gta04-0b599603d8534bc3946a0f07e461c76d7947dfcf.tar.bz2 |
spi/imx: add support for imx51's eCSPI and CSPI
i.MX51 comes with two eCSPI interfaces (that are quite different from
what was known before---the tried and tested Freescale way) and a CSPI
interface that is identical to the devices found on i.MX25 and i.MX35.
This patch is a merge of two very similar patches (by Jason Wang and Sascha
Hauer resp.) plus a (now hopefully correct) reimplementation of the
clock calculation.
Acked-by: Jason Wang <jason77.wang@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/Kconfig | 5 | ||||
-rw-r--r-- | drivers/spi/spi_imx.c | 140 |
2 files changed, 143 insertions, 2 deletions
diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 4e9d77b..7e631fa 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -153,7 +153,10 @@ config SPI_IMX_VER_0_4 def_bool y if ARCH_MX31 config SPI_IMX_VER_0_7 - def_bool y if ARCH_MX25 || ARCH_MX35 + def_bool y if ARCH_MX25 || ARCH_MX35 || ARCH_MX51 + +config SPI_IMX_VER_2_3 + def_bool y if ARCH_MX51 config SPI_IMX tristate "Freescale i.MX SPI controllers" diff --git a/drivers/spi/spi_imx.c b/drivers/spi/spi_imx.c index 23db984..6bab2cf 100644 --- a/drivers/spi/spi_imx.c +++ b/drivers/spi/spi_imx.c @@ -65,6 +65,7 @@ enum spi_imx_devtype { SPI_IMX_VER_0_4, SPI_IMX_VER_0_5, SPI_IMX_VER_0_7, + SPI_IMX_VER_2_3, SPI_IMX_VER_AUTODETECT, }; @@ -155,7 +156,7 @@ static unsigned int spi_imx_clkdiv_1(unsigned int fin, return max; } -/* MX1, MX31, MX35 */ +/* MX1, MX31, MX35, MX51 CSPI */ static unsigned int spi_imx_clkdiv_2(unsigned int fin, unsigned int fspi) { @@ -170,6 +171,128 @@ static unsigned int spi_imx_clkdiv_2(unsigned int fin, return 7; } +#define SPI_IMX2_3_CTRL 0x08 +#define SPI_IMX2_3_CTRL_ENABLE (1 << 0) +#define SPI_IMX2_3_CTRL_XCH (1 << 2) +#define SPI_IMX2_3_CTRL_MODE(cs) (1 << ((cs) + 4)) +#define SPI_IMX2_3_CTRL_POSTDIV_OFFSET 8 +#define SPI_IMX2_3_CTRL_PREDIV_OFFSET 12 +#define SPI_IMX2_3_CTRL_CS(cs) ((cs) << 18) +#define SPI_IMX2_3_CTRL_BL_OFFSET 20 + +#define SPI_IMX2_3_CONFIG 0x0c +#define SPI_IMX2_3_CONFIG_SCLKPHA(cs) (1 << ((cs) + 0)) +#define SPI_IMX2_3_CONFIG_SCLKPOL(cs) (1 << ((cs) + 4)) +#define SPI_IMX2_3_CONFIG_SBBCTRL(cs) (1 << ((cs) + 8)) +#define SPI_IMX2_3_CONFIG_SSBPOL(cs) (1 << ((cs) + 12)) + +#define SPI_IMX2_3_INT 0x10 +#define SPI_IMX2_3_INT_TEEN (1 << 0) +#define SPI_IMX2_3_INT_RREN (1 << 3) + +#define SPI_IMX2_3_STAT 0x18 +#define SPI_IMX2_3_STAT_RR (1 << 3) + +/* MX51 eCSPI */ +static unsigned int spi_imx2_3_clkdiv(unsigned int fin, unsigned int fspi) +{ + /* + * there are two 4-bit dividers, the pre-divider divides by + * $pre, the post-divider by 2^$post + */ + unsigned int pre, post; + + if (unlikely(fspi > fin)) + return 0; + + post = fls(fin) - fls(fspi); + if (fin > fspi << post) + post++; + + /* now we have: (fin <= fspi << post) with post being minimal */ + + post = max(4U, post) - 4; + if (unlikely(post > 0xf)) { + pr_err("%s: cannot set clock freq: %u (base freq: %u)\n", + __func__, fspi, fin); + return 0xff; + } + + pre = DIV_ROUND_UP(fin, fspi << post) - 1; + + pr_debug("%s: fin: %u, fspi: %u, post: %u, pre: %u\n", + __func__, fin, fspi, post, pre); + return (pre << SPI_IMX2_3_CTRL_PREDIV_OFFSET) | + (post << SPI_IMX2_3_CTRL_POSTDIV_OFFSET); +} + +static void __maybe_unused spi_imx2_3_intctrl(struct spi_imx_data *spi_imx, int enable) +{ + unsigned val = 0; + + if (enable & MXC_INT_TE) + val |= SPI_IMX2_3_INT_TEEN; + + if (enable & MXC_INT_RR) + val |= SPI_IMX2_3_INT_RREN; + + writel(val, spi_imx->base + SPI_IMX2_3_INT); +} + +static void __maybe_unused spi_imx2_3_trigger(struct spi_imx_data *spi_imx) +{ + u32 reg; + + reg = readl(spi_imx->base + SPI_IMX2_3_CTRL); + reg |= SPI_IMX2_3_CTRL_XCH; + writel(reg, spi_imx->base + SPI_IMX2_3_CTRL); +} + +static int __maybe_unused spi_imx2_3_config(struct spi_imx_data *spi_imx, + struct spi_imx_config *config) +{ + u32 ctrl = SPI_IMX2_3_CTRL_ENABLE, cfg = 0; + + /* set master mode */ + ctrl |= SPI_IMX2_3_CTRL_MODE(config->cs); + + /* set clock speed */ + ctrl |= spi_imx2_3_clkdiv(spi_imx->spi_clk, config->speed_hz); + + /* set chip select to use */ + ctrl |= SPI_IMX2_3_CTRL_CS(config->cs); + + ctrl |= (config->bpw - 1) << SPI_IMX2_3_CTRL_BL_OFFSET; + + cfg |= SPI_IMX2_3_CONFIG_SBBCTRL(config->cs); + + if (config->mode & SPI_CPHA) + cfg |= SPI_IMX2_3_CONFIG_SCLKPHA(config->cs); + + if (config->mode & SPI_CPOL) + cfg |= SPI_IMX2_3_CONFIG_SCLKPOL(config->cs); + + if (config->mode & SPI_CS_HIGH) + cfg |= SPI_IMX2_3_CONFIG_SSBPOL(config->cs); + + writel(ctrl, spi_imx->base + SPI_IMX2_3_CTRL); + writel(cfg, spi_imx->base + SPI_IMX2_3_CONFIG); + + return 0; +} + +static int __maybe_unused spi_imx2_3_rx_available(struct spi_imx_data *spi_imx) +{ + return readl(spi_imx->base + SPI_IMX2_3_STAT) & SPI_IMX2_3_STAT_RR; +} + +static void __maybe_unused spi_imx2_3_reset(struct spi_imx_data *spi_imx) +{ + /* drain receive buffer */ + while (spi_imx2_3_rx_available(spi_imx)) + readl(spi_imx->base + MXC_CSPIRXDATA); +} + #define MX31_INTREG_TEEN (1 << 0) #define MX31_INTREG_RREN (1 << 3) @@ -447,6 +570,15 @@ static struct spi_imx_devtype_data spi_imx_devtype_data[] __devinitdata = { .reset = spi_imx0_4_reset, }, #endif +#ifdef CONFIG_SPI_IMX_VER_2_3 + [SPI_IMX_VER_2_3] = { + .intctrl = spi_imx2_3_intctrl, + .config = spi_imx2_3_config, + .trigger = spi_imx2_3_trigger, + .rx_available = spi_imx2_3_rx_available, + .reset = spi_imx2_3_reset, + }, +#endif }; static void spi_imx_chipselect(struct spi_device *spi, int is_active) @@ -603,6 +735,12 @@ static struct platform_device_id spi_imx_devtype[] = { .name = "imx35-cspi", .driver_data = SPI_IMX_VER_0_7, }, { + .name = "imx51-cspi", + .driver_data = SPI_IMX_VER_0_7, + }, { + .name = "imx51-ecspi", + .driver_data = SPI_IMX_VER_2_3, + }, { /* sentinel */ } }; |