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Diffstat (limited to 'drivers/mmc/host/mmc_spi.c')
-rw-r--r--drivers/mmc/host/mmc_spi.c188
1 files changed, 133 insertions, 55 deletions
diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c
index 72f8bde..f48349d 100644
--- a/drivers/mmc/host/mmc_spi.c
+++ b/drivers/mmc/host/mmc_spi.c
@@ -24,7 +24,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
-#include <linux/hrtimer.h>
+#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/bio.h>
#include <linux/dma-mapping.h>
@@ -95,7 +95,7 @@
* reads which takes nowhere near that long. Older cards may be able to use
* shorter timeouts ... but why bother?
*/
-#define r1b_timeout ktime_set(3, 0)
+#define r1b_timeout (HZ * 3)
/****************************************************************************/
@@ -183,12 +183,11 @@ mmc_spi_readbytes(struct mmc_spi_host *host, unsigned len)
return status;
}
-static int
-mmc_spi_skip(struct mmc_spi_host *host, ktime_t timeout, unsigned n, u8 byte)
+static int mmc_spi_skip(struct mmc_spi_host *host, unsigned long timeout,
+ unsigned n, u8 byte)
{
u8 *cp = host->data->status;
-
- timeout = ktime_add(timeout, ktime_get());
+ unsigned long start = jiffies;
while (1) {
int status;
@@ -203,22 +202,26 @@ mmc_spi_skip(struct mmc_spi_host *host, ktime_t timeout, unsigned n, u8 byte)
return cp[i];
}
- /* REVISIT investigate msleep() to avoid busy-wait I/O
- * in at least some cases.
- */
- if (ktime_to_ns(ktime_sub(ktime_get(), timeout)) > 0)
+ if (time_is_before_jiffies(start + timeout))
break;
+
+ /* If we need long timeouts, we may release the CPU.
+ * We use jiffies here because we want to have a relation
+ * between elapsed time and the blocking of the scheduler.
+ */
+ if (time_is_before_jiffies(start+1))
+ schedule();
}
return -ETIMEDOUT;
}
static inline int
-mmc_spi_wait_unbusy(struct mmc_spi_host *host, ktime_t timeout)
+mmc_spi_wait_unbusy(struct mmc_spi_host *host, unsigned long timeout)
{
return mmc_spi_skip(host, timeout, sizeof(host->data->status), 0);
}
-static int mmc_spi_readtoken(struct mmc_spi_host *host, ktime_t timeout)
+static int mmc_spi_readtoken(struct mmc_spi_host *host, unsigned long timeout)
{
return mmc_spi_skip(host, timeout, 1, 0xff);
}
@@ -251,6 +254,10 @@ static int mmc_spi_response_get(struct mmc_spi_host *host,
u8 *cp = host->data->status;
u8 *end = cp + host->t.len;
int value = 0;
+ int bitshift;
+ u8 leftover = 0;
+ unsigned short rotator;
+ int i;
char tag[32];
snprintf(tag, sizeof(tag), " ... CMD%d response SPI_%s",
@@ -268,9 +275,8 @@ static int mmc_spi_response_get(struct mmc_spi_host *host,
/* Data block reads (R1 response types) may need more data... */
if (cp == end) {
- unsigned i;
-
cp = host->data->status;
+ end = cp+1;
/* Card sends N(CR) (== 1..8) bytes of all-ones then one
* status byte ... and we already scanned 2 bytes.
@@ -295,20 +301,34 @@ static int mmc_spi_response_get(struct mmc_spi_host *host,
}
checkstatus:
- if (*cp & 0x80) {
- dev_dbg(&host->spi->dev, "%s: INVALID RESPONSE, %02x\n",
- tag, *cp);
- value = -EBADR;
- goto done;
+ bitshift = 0;
+ if (*cp & 0x80) {
+ /* Houston, we have an ugly card with a bit-shifted response */
+ rotator = *cp++ << 8;
+ /* read the next byte */
+ if (cp == end) {
+ value = mmc_spi_readbytes(host, 1);
+ if (value < 0)
+ goto done;
+ cp = host->data->status;
+ end = cp+1;
+ }
+ rotator |= *cp++;
+ while (rotator & 0x8000) {
+ bitshift++;
+ rotator <<= 1;
+ }
+ cmd->resp[0] = rotator >> 8;
+ leftover = rotator;
+ } else {
+ cmd->resp[0] = *cp++;
}
-
- cmd->resp[0] = *cp++;
cmd->error = 0;
/* Status byte: the entire seven-bit R1 response. */
if (cmd->resp[0] != 0) {
if ((R1_SPI_PARAMETER | R1_SPI_ADDRESS
- | R1_SPI_ILLEGAL_COMMAND)
+ | R1_SPI_ILLEGAL_COMMAND)
& cmd->resp[0])
value = -EINVAL;
else if (R1_SPI_COM_CRC & cmd->resp[0])
@@ -336,12 +356,45 @@ checkstatus:
* SPI R5 == R1 + data byte; IO_RW_DIRECT
*/
case MMC_RSP_SPI_R2:
- cmd->resp[0] |= *cp << 8;
+ /* read the next byte */
+ if (cp == end) {
+ value = mmc_spi_readbytes(host, 1);
+ if (value < 0)
+ goto done;
+ cp = host->data->status;
+ end = cp+1;
+ }
+ if (bitshift) {
+ rotator = leftover << 8;
+ rotator |= *cp << bitshift;
+ cmd->resp[0] |= (rotator & 0xFF00);
+ } else {
+ cmd->resp[0] |= *cp << 8;
+ }
break;
/* SPI R3, R4, or R7 == R1 + 4 bytes */
case MMC_RSP_SPI_R3:
- cmd->resp[1] = get_unaligned_be32(cp);
+ rotator = leftover << 8;
+ cmd->resp[1] = 0;
+ for (i = 0; i < 4; i++) {
+ cmd->resp[1] <<= 8;
+ /* read the next byte */
+ if (cp == end) {
+ value = mmc_spi_readbytes(host, 1);
+ if (value < 0)
+ goto done;
+ cp = host->data->status;
+ end = cp+1;
+ }
+ if (bitshift) {
+ rotator |= *cp++ << bitshift;
+ cmd->resp[1] |= (rotator >> 8);
+ rotator <<= 8;
+ } else {
+ cmd->resp[1] |= *cp++;
+ }
+ }
break;
/* SPI R1 == just one status byte */
@@ -607,7 +660,7 @@ mmc_spi_setup_data_message(
*/
static int
mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t,
- ktime_t timeout)
+ unsigned long timeout)
{
struct spi_device *spi = host->spi;
int status, i;
@@ -717,11 +770,13 @@ mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t,
*/
static int
mmc_spi_readblock(struct mmc_spi_host *host, struct spi_transfer *t,
- ktime_t timeout)
+ unsigned long timeout)
{
struct spi_device *spi = host->spi;
int status;
struct scratch *scratch = host->data;
+ unsigned int bitshift;
+ u8 leftover;
/* At least one SD card sends an all-zeroes byte when N(CX)
* applies, before the all-ones bytes ... just cope with that.
@@ -733,38 +788,60 @@ mmc_spi_readblock(struct mmc_spi_host *host, struct spi_transfer *t,
if (status == 0xff || status == 0)
status = mmc_spi_readtoken(host, timeout);
- if (status == SPI_TOKEN_SINGLE) {
- if (host->dma_dev) {
- dma_sync_single_for_device(host->dma_dev,
- host->data_dma, sizeof(*scratch),
- DMA_BIDIRECTIONAL);
- dma_sync_single_for_device(host->dma_dev,
- t->rx_dma, t->len,
- DMA_FROM_DEVICE);
- }
+ if (status < 0) {
+ dev_dbg(&spi->dev, "read error %02x (%d)\n", status, status);
+ return status;
+ }
- status = spi_sync(spi, &host->m);
+ /* The token may be bit-shifted...
+ * the first 0-bit precedes the data stream.
+ */
+ bitshift = 7;
+ while (status & 0x80) {
+ status <<= 1;
+ bitshift--;
+ }
+ leftover = status << 1;
- if (host->dma_dev) {
- dma_sync_single_for_cpu(host->dma_dev,
- host->data_dma, sizeof(*scratch),
- DMA_BIDIRECTIONAL);
- dma_sync_single_for_cpu(host->dma_dev,
- t->rx_dma, t->len,
- DMA_FROM_DEVICE);
- }
+ if (host->dma_dev) {
+ dma_sync_single_for_device(host->dma_dev,
+ host->data_dma, sizeof(*scratch),
+ DMA_BIDIRECTIONAL);
+ dma_sync_single_for_device(host->dma_dev,
+ t->rx_dma, t->len,
+ DMA_FROM_DEVICE);
+ }
- } else {
- dev_dbg(&spi->dev, "read error %02x (%d)\n", status, status);
+ status = spi_sync(spi, &host->m);
- /* we've read extra garbage, timed out, etc */
- if (status < 0)
- return status;
+ if (host->dma_dev) {
+ dma_sync_single_for_cpu(host->dma_dev,
+ host->data_dma, sizeof(*scratch),
+ DMA_BIDIRECTIONAL);
+ dma_sync_single_for_cpu(host->dma_dev,
+ t->rx_dma, t->len,
+ DMA_FROM_DEVICE);
+ }
- /* low four bits are an R2 subset, fifth seems to be
- * vendor specific ... map them all to generic error..
+ if (bitshift) {
+ /* Walk through the data and the crc and do
+ * all the magic to get byte-aligned data.
*/
- return -EIO;
+ u8 *cp = t->rx_buf;
+ unsigned int len;
+ unsigned int bitright = 8 - bitshift;
+ u8 temp;
+ for (len = t->len; len; len--) {
+ temp = *cp;
+ *cp++ = leftover | (temp >> bitshift);
+ leftover = temp << bitright;
+ }
+ cp = (u8 *) &scratch->crc_val;
+ temp = *cp;
+ *cp++ = leftover | (temp >> bitshift);
+ leftover = temp << bitright;
+ temp = *cp;
+ *cp = leftover | (temp >> bitshift);
}
if (host->mmc->use_spi_crc) {
@@ -803,7 +880,7 @@ mmc_spi_data_do(struct mmc_spi_host *host, struct mmc_command *cmd,
unsigned n_sg;
int multiple = (data->blocks > 1);
u32 clock_rate;
- ktime_t timeout;
+ unsigned long timeout;
if (data->flags & MMC_DATA_READ)
direction = DMA_FROM_DEVICE;
@@ -817,8 +894,9 @@ mmc_spi_data_do(struct mmc_spi_host *host, struct mmc_command *cmd,
else
clock_rate = spi->max_speed_hz;
- timeout = ktime_add_ns(ktime_set(0, 0), data->timeout_ns +
- data->timeout_clks * 1000000 / clock_rate);
+ timeout = data->timeout_ns +
+ data->timeout_clks * 1000000 / clock_rate;
+ timeout = usecs_to_jiffies((unsigned int)(timeout / 1000)) + 1;
/* Handle scatterlist segments one at a time, with synch for
* each 512-byte block
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