From c4ea142424fc5cb43a2db750cb772e84304e5fb8 Mon Sep 17 00:00:00 2001 From: Stefano Babic Date: Tue, 6 Jul 2010 17:05:06 +0200 Subject: Use common function to set GPIOs for MX3 and MX5 The patch adds support for setting gpios to the MX51 processor and change name to the corresponding functions for MX31. In this way, it is possible to get rid of nasty #ifdef switches related to the processor type. Signed-off-by: Stefano Babic --- drivers/spi/mxc_spi.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c index e15a63c..802cd2e 100644 --- a/drivers/spi/mxc_spi.c +++ b/drivers/spi/mxc_spi.c @@ -23,6 +23,7 @@ #include #include #include +#include #ifdef CONFIG_MX27 /* i.MX27 has a completely wrong register layout and register definitions in the @@ -68,9 +69,6 @@ static unsigned long spi_bases[] = { 0x53f84000, }; -#define OUT MX31_GPIO_DIRECTION_OUT -#define mxc_gpio_direction mx31_gpio_direction -#define mxc_gpio_set mx31_gpio_set #elif defined(CONFIG_MX51) #include #include @@ -111,13 +109,12 @@ static unsigned long spi_bases[] = { CSPI2_BASE_ADDR, CSPI3_BASE_ADDR, }; -#define mxc_gpio_direction(gpio, dir) (0) -#define mxc_gpio_set(gpio, value) {} -#define OUT 1 #else #error "Unsupported architecture" #endif +#define OUT MXC_GPIO_DIRECTION_OUT + struct mxc_spi_slave { struct spi_slave slave; unsigned long base; @@ -126,6 +123,7 @@ struct mxc_spi_slave { u32 cfg_reg; #endif int gpio; + int ss_pol; }; static inline struct mxc_spi_slave *to_mxc_spi_slave(struct spi_slave *slave) @@ -147,7 +145,7 @@ void spi_cs_activate(struct spi_slave *slave) { struct mxc_spi_slave *mxcs = to_mxc_spi_slave(slave); if (mxcs->gpio > 0) - mxc_gpio_set(mxcs->gpio, mxcs->ctrl_reg & MXC_CSPICTRL_SSPOL); + mxc_gpio_set(mxcs->gpio, mxcs->ss_pol); } void spi_cs_deactivate(struct spi_slave *slave) @@ -155,7 +153,7 @@ void spi_cs_deactivate(struct spi_slave *slave) struct mxc_spi_slave *mxcs = to_mxc_spi_slave(slave); if (mxcs->gpio > 0) mxc_gpio_set(mxcs->gpio, - !(mxcs->ctrl_reg & MXC_CSPICTRL_SSPOL)); + !(mxcs->ss_pol)); } #ifdef CONFIG_MX51 @@ -394,6 +392,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, mxcs->slave.bus = bus; mxcs->slave.cs = cs; mxcs->base = spi_bases[bus]; + mxcs->ss_pol = (mode & SPI_CS_HIGH) ? 1 : 0; #ifdef CONFIG_MX51 /* Can be used for i.MX31 too ? */ -- cgit v1.1 From 9f481e95baaca2a5a739f930c16b1cc485b0c1f3 Mon Sep 17 00:00:00 2001 From: Stefano Babic Date: Mon, 23 Aug 2010 20:41:19 +0200 Subject: MXC: Correct SPI_CPOL setting in SPI driver The handling of the SPI_CPOL bit inside the SPI driver was wrong. As reported by the manual, the meaning of the SSPOL inside the configuration register is the same as reported by SPI specification (0 if low in idle, 1 is high on idle). The driver inverts this logic. Because this patch sets the logic as specified, it is required to clear the CPOL bit in the configuration file to adapt to the correct logic. Signed-off-by: Stefano Babic Signed-off-by: David Jander --- drivers/spi/mxc_spi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c index 802cd2e..c6c8f60 100644 --- a/drivers/spi/mxc_spi.c +++ b/drivers/spi/mxc_spi.c @@ -215,7 +215,7 @@ static s32 spi_cfg(struct mxc_spi_slave *mxcs, unsigned int cs, if (mode & SPI_CS_HIGH) ss_pol = 1; - if (!(mode & SPI_CPOL)) + if (mode & SPI_CPOL) sclkpol = 1; if (mode & SPI_CPHA) @@ -412,7 +412,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, if (mode & SPI_CPHA) ctrl_reg |= MXC_CSPICTRL_PHA; - if (!(mode & SPI_CPOL)) + if (mode & SPI_CPOL) ctrl_reg |= MXC_CSPICTRL_POL; if (mode & SPI_CS_HIGH) ctrl_reg |= MXC_CSPICTRL_SSPOL; -- cgit v1.1 From 2f721d17339ee22bbc14fb0bb1dad20b82871923 Mon Sep 17 00:00:00 2001 From: Stefano Babic Date: Fri, 20 Aug 2010 12:05:03 +0200 Subject: MXC: Fix byte-ordering in SPI driver for i.MX31/i.MX51 The actual SPI driver for i.MX31 and i.MX51 controller use a wrong byte ordering, because it is supposed to work only with Freescale's devices, as the Power Controllers (PMIC). The driver is not suitable for general purposes, because the buffers passed to spi_xfer must be 32-bit aligned, as it is used mainly to send integer to PMIC devices. The patch drops any kind of limitation and makes the driver useful with devices controlled sending commands composed by single bytes (or by a odd number of bytes), such as spi flash, sensor, etc. Because the byte ordering is changed, any current driver using this controller must be adapted, too. Signed-off-by: Stefano Babic --- drivers/spi/mxc_spi.c | 149 +++++++++++++++++++++++++++++++++++++------------- 1 file changed, 111 insertions(+), 38 deletions(-) (limited to 'drivers/spi') diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c index c6c8f60..d558137 100644 --- a/drivers/spi/mxc_spi.c +++ b/drivers/spi/mxc_spi.c @@ -62,6 +62,7 @@ #define MXC_CSPICTRL_MAXBITS 0x1f #define MXC_CSPIPERIOD_32KHZ (1 << 15) +#define MAX_SPI_BYTES 4 static unsigned long spi_bases[] = { 0x43fa4000, @@ -95,6 +96,7 @@ static unsigned long spi_bases[] = { #define MXC_CSPICTRL_RXOVF (1 << 6) #define MXC_CSPIPERIOD_32KHZ (1 << 15) +#define MAX_SPI_BYTES 32 /* Bit position inside CTRL register to be associated with SS */ #define MXC_CSPICTRL_CHAN 18 @@ -252,13 +254,15 @@ static s32 spi_cfg(struct mxc_spi_slave *mxcs, unsigned int cs, } #endif -static u32 spi_xchg_single(struct spi_slave *slave, u32 data, int bitlen, - unsigned long flags) +int spi_xchg_single(struct spi_slave *slave, unsigned int bitlen, + const u8 *dout, u8 *din, unsigned long flags) { struct mxc_spi_slave *mxcs = to_mxc_spi_slave(slave); + int nbytes = (bitlen + 7) / 8; + u32 data, cnt, i; - if (flags & SPI_XFER_BEGIN) - spi_cs_activate(slave); + debug("%s: bitlen %d dout 0x%x din 0x%x\n", + __func__, bitlen, (u32)dout, (u32)din); mxcs->ctrl_reg = (mxcs->ctrl_reg & ~MXC_CSPICTRL_BITCOUNT(MXC_CSPICTRL_MAXBITS)) | @@ -273,8 +277,46 @@ static u32 spi_xchg_single(struct spi_slave *slave, u32 data, int bitlen, reg_write(mxcs->base + MXC_CSPISTAT, MXC_CSPICTRL_TC | MXC_CSPICTRL_RXOVF); - debug("Sending SPI 0x%x\n", data); - reg_write(mxcs->base + MXC_CSPITXDATA, data); + /* + * The SPI controller works only with words, + * check if less than a word is sent. + * Access to the FIFO is only 32 bit + */ + if (bitlen % 32) { + data = 0; + cnt = (bitlen % 32) / 8; + if (dout) { + for (i = 0; i < cnt; i++) { + data = (data << 8) | (*dout++ & 0xFF); + } + } + debug("Sending SPI 0x%x\n", data); + + reg_write(mxcs->base + MXC_CSPITXDATA, data); + nbytes -= cnt; + } + + data = 0; + + while (nbytes > 0) { + data = 0; + if (dout) { + /* Buffer is not 32-bit aligned */ + if ((unsigned long)dout & 0x03) { + data = 0; + for (i = 0; i < 4; i++, data <<= 8) { + data = (data << 8) | (*dout++ & 0xFF); + } + } else { + data = *(u32 *)dout; + data = cpu_to_be32(data); + } + dout += 4; + } + debug("Sending SPI 0x%x\n", data); + reg_write(mxcs->base + MXC_CSPITXDATA, data); + nbytes -= 4; + } /* FIFO is written, now starts the transfer setting the XCH bit */ reg_write(mxcs->base + MXC_CSPICTRL, mxcs->ctrl_reg | @@ -288,49 +330,78 @@ static u32 spi_xchg_single(struct spi_slave *slave, u32 data, int bitlen, reg_write(mxcs->base + MXC_CSPISTAT, MXC_CSPICTRL_TC | MXC_CSPICTRL_RXOVF); - data = reg_read(mxcs->base + MXC_CSPIRXDATA); - debug("SPI Rx: 0x%x\n", data); + nbytes = (bitlen + 7) / 8; - if (flags & SPI_XFER_END) - spi_cs_deactivate(slave); + cnt = nbytes % 32; - return data; + if (bitlen % 32) { + data = reg_read(mxcs->base + MXC_CSPIRXDATA); + cnt = (bitlen % 32) / 8; + debug("SPI Rx unaligned: 0x%x\n", data); + if (din) { + for (i = 0; i < cnt; i++, data >>= 8) { + *din++ = data & 0xFF; + } + } + nbytes -= cnt; + } + + while (nbytes > 0) { + u32 tmp; + tmp = reg_read(mxcs->base + MXC_CSPIRXDATA); + data = cpu_to_be32(tmp); + debug("SPI Rx: 0x%x 0x%x\n", tmp, data); + cnt = min(nbytes, sizeof(data)); + if (din) { + memcpy(din, &data, cnt); + din += cnt; + } + nbytes -= cnt; + } + + return 0; } + int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, void *din, unsigned long flags) { - int n_blks = (bitlen + 31) / 32; - u32 *out_l, *in_l; - int i; + int n_bytes = (bitlen + 7) / 8; + int n_bits; + int ret; + u32 blk_size; + u8 *p_outbuf = (u8 *)dout; + u8 *p_inbuf = (u8 *)din; - if ((int)dout & 3 || (int)din & 3) { - printf("Error: unaligned buffers in: %p, out: %p\n", din, dout); - return 1; - } + if (!slave) + return -1; - /* This driver is currently partly broken, alert the user */ - if (bitlen > 16 && (bitlen % 32)) { - printf("Error: SPI transfer with bitlen=%d is broken.\n", - bitlen); - return 1; + if (flags & SPI_XFER_BEGIN) + spi_cs_activate(slave); + + while (n_bytes > 0) { + + if (n_bytes < MAX_SPI_BYTES) + blk_size = n_bytes; + else + blk_size = MAX_SPI_BYTES; + + n_bits = blk_size * 8; + + ret = spi_xchg_single(slave, n_bits, p_outbuf, p_inbuf, 0); + + if (ret) + return ret; + if (dout) + p_outbuf += blk_size; + if (din) + p_inbuf += blk_size; + n_bytes -= blk_size; } - for (i = 0, in_l = (u32 *)din, out_l = (u32 *)dout; - i < n_blks; - i++, in_l++, out_l++, bitlen -= 32) { - u32 data = spi_xchg_single(slave, *out_l, bitlen, flags); - - /* Check if we're only transfering 8 or 16 bits */ - if (!i) { - if (bitlen < 9) - *(u8 *)din = data; - else if (bitlen < 17) - *(u16 *)din = data; - else - *in_l = data; - } + if (flags & SPI_XFER_END) { + spi_cs_deactivate(slave); } return 0; @@ -378,8 +449,10 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, return NULL; mxcs = malloc(sizeof(struct mxc_spi_slave)); - if (!mxcs) + if (!mxcs) { + puts("mxc_spi: SPI Slave not allocated !\n"); return NULL; + } ret = decode_cs(mxcs, cs); if (ret < 0) { -- cgit v1.1