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path: root/drivers/spi/mxc_spi.c
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Diffstat (limited to 'drivers/spi/mxc_spi.c')
-rw-r--r--drivers/spi/mxc_spi.c168
1 files changed, 120 insertions, 48 deletions
diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c
index e15a63cac..d558137c9 100644
--- a/drivers/spi/mxc_spi.c
+++ b/drivers/spi/mxc_spi.c
@@ -23,6 +23,7 @@
#include <spi.h>
#include <asm/errno.h>
#include <asm/io.h>
+#include <mxc_gpio.h>
#ifdef CONFIG_MX27
/* i.MX27 has a completely wrong register layout and register definitions in the
@@ -61,6 +62,7 @@
#define MXC_CSPICTRL_MAXBITS 0x1f
#define MXC_CSPIPERIOD_32KHZ (1 << 15)
+#define MAX_SPI_BYTES 4
static unsigned long spi_bases[] = {
0x43fa4000,
@@ -68,9 +70,6 @@ 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 <asm/arch/imx-regs.h>
#include <asm/arch/clock.h>
@@ -97,6 +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
@@ -111,13 +111,12 @@ 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 +125,7 @@ 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 +147,7 @@ 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 +155,7 @@ 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
@@ -217,7 +217,7 @@ 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)
@@ -254,13 +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)) |
@@ -275,8 +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 |
@@ -290,49 +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;
+
+ 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;
+ }
- return data;
+ 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);
- 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);
+ while (n_bytes > 0) {
- /* 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 (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;
+ }
+
+ if (flags & SPI_XFER_END) {
+ spi_cs_deactivate(slave);
}
return 0;
@@ -380,8 +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) {
@@ -394,6 +465,7 @@ 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 ? */
@@ -413,7 +485,7 @@ 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;
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-11-04 05:01:23 +0000