From 48881caec426786cd451383ee53943cc5d3bfdeb Mon Sep 17 00:00:00 2001 From: Wolfgang Muees Date: Wed, 11 Mar 2009 14:13:15 +0100 Subject: mmc_spi: allow setting of spi mode 3 Allow the platform data structures to specify spi mode 3 (if there is a pullup on the clock line or the spi hardware is not able to serve spi mode 0). Signed-off-by: Wolfgang Muees Acked-by: David Brownell Signed-off-by: Pierre Ossman --- drivers/mmc/host/mmc_spi.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'drivers/mmc/host/mmc_spi.c') diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c index 87e211df68a..ad9e0e213f6 100644 --- a/drivers/mmc/host/mmc_spi.c +++ b/drivers/mmc/host/mmc_spi.c @@ -1204,10 +1204,12 @@ static int mmc_spi_probe(struct spi_device *spi) /* MMC and SD specs only seem to care that sampling is on the * rising edge ... meaning SPI modes 0 or 3. So either SPI mode - * should be legit. We'll use mode 0 since it seems to be a - * bit less troublesome on some hardware ... unclear why. + * should be legit. We'll use mode 0 since the steady state is 0, + * which is appropriate for hotplugging, unless the platform data + * specify mode 3 (if hardware is not compatible to mode 0). */ - spi->mode = SPI_MODE_0; + if (spi->mode != SPI_MODE_3) + spi->mode = SPI_MODE_0; spi->bits_per_word = 8; status = spi_setup(spi); -- cgit v1.2.3-70-g09d2 From ea15ba5cd7bb370902cd9f6a73c2d288bfba6b2c Mon Sep 17 00:00:00 2001 From: Wolfgang Muees Date: Wed, 11 Mar 2009 14:17:43 +0100 Subject: mmc_spi: wait more bytes for card response Some cards are slower than the standard allows and need more time to respond to a command. Max. observed number of bytes was 12. Signed-off-by: Wolfgang Muees Acked-by: David Brownell Signed-off-by: Pierre Ossman --- drivers/mmc/host/mmc_spi.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers/mmc/host/mmc_spi.c') diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c index ad9e0e213f6..69e1442ff2e 100644 --- a/drivers/mmc/host/mmc_spi.c +++ b/drivers/mmc/host/mmc_spi.c @@ -279,8 +279,11 @@ static int mmc_spi_response_get(struct mmc_spi_host *host, * so it can always DMA directly into the target buffer. * It'd probably be better to memcpy() the first chunk and * avoid extra i/o calls... + * + * Note we check for more than 8 bytes, because in practice, + * some SD cards are slow... */ - for (i = 2; i < 9; i++) { + for (i = 2; i < 16; i++) { value = mmc_spi_readbytes(host, 1); if (value < 0) goto done; -- cgit v1.2.3-70-g09d2 From f079a8fc61e3dc35830f6abc58c21ae815ab4297 Mon Sep 17 00:00:00 2001 From: Wolfgang Muees Date: Mon, 16 Mar 2009 12:23:03 +0100 Subject: mmc_spi: adjust for delayed data token response Some cards are not able to send the data token in time, but miss the time frame for some bits(!). So synchronize to the start of the token. Signed-off-by: Wolfgang Muees Acked-by: David Brownell Signed-off-by: Pierre Ossman --- drivers/mmc/host/mmc_spi.c | 27 ++++++++++++++++++++++++--- 1 file changed, 24 insertions(+), 3 deletions(-) (limited to 'drivers/mmc/host/mmc_spi.c') diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c index 69e1442ff2e..72f8bde4877 100644 --- a/drivers/mmc/host/mmc_spi.c +++ b/drivers/mmc/host/mmc_spi.c @@ -612,6 +612,7 @@ mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t, struct spi_device *spi = host->spi; int status, i; struct scratch *scratch = host->data; + u32 pattern; if (host->mmc->use_spi_crc) scratch->crc_val = cpu_to_be16( @@ -639,8 +640,27 @@ mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t, * doesn't necessarily tell whether the write operation succeeded; * it just says if the transmission was ok and whether *earlier* * writes succeeded; see the standard. + * + * In practice, there are (even modern SDHC-)cards which are late + * in sending the response, and miss the time frame by a few bits, + * so we have to cope with this situation and check the response + * bit-by-bit. Arggh!!! */ - switch (SPI_MMC_RESPONSE_CODE(scratch->status[0])) { + pattern = scratch->status[0] << 24; + pattern |= scratch->status[1] << 16; + pattern |= scratch->status[2] << 8; + pattern |= scratch->status[3]; + + /* First 3 bit of pattern are undefined */ + pattern |= 0xE0000000; + + /* left-adjust to leading 0 bit */ + while (pattern & 0x80000000) + pattern <<= 1; + /* right-adjust for pattern matching. Code is in bit 4..0 now. */ + pattern >>= 27; + + switch (pattern) { case SPI_RESPONSE_ACCEPTED: status = 0; break; @@ -671,8 +691,9 @@ mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t, /* Return when not busy. If we didn't collect that status yet, * we'll need some more I/O. */ - for (i = 1; i < sizeof(scratch->status); i++) { - if (scratch->status[i] != 0) + for (i = 4; i < sizeof(scratch->status); i++) { + /* card is non-busy if the most recent bit is 1 */ + if (scratch->status[i] & 0x01) return 0; } return mmc_spi_wait_unbusy(host, timeout); -- cgit v1.2.3-70-g09d2 From 56e303ebeec7ef43dbd9d7998f8ad1a9f75d59bc Mon Sep 17 00:00:00 2001 From: Wolfgang Muees Date: Tue, 7 Apr 2009 15:26:30 +0100 Subject: mmc_spi: convert timeout handling to jiffies and avoid busy waiting SD/MMC card timeouts can be very high. So avoid busy-waiting, using the scheduler. Calculate all timeouts in jiffies units, because this will give us the correct sign when to involve the scheduler. Signed-off-by: Wolfgang Muees Signed-off-by: Pierre Ossman --- drivers/mmc/host/mmc_spi.c | 38 +++++++++++++++++++++----------------- 1 file changed, 21 insertions(+), 17 deletions(-) (limited to 'drivers/mmc/host/mmc_spi.c') diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c index 72f8bde4877..ed02ebd899d 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 +#include #include #include #include @@ -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); } @@ -607,7 +610,7 @@ 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; @@ -717,7 +720,7 @@ 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; @@ -803,7 +806,7 @@ 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 +820,9 @@ 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 -- cgit v1.2.3-70-g09d2 From ab5a643cf597f2214feb6ff7288c72589661bde1 Mon Sep 17 00:00:00 2001 From: Wolfgang Muees Date: Wed, 8 Apr 2009 09:48:58 +0100 Subject: mmc_spi: support for non-byte-aligned cards A very large subset of SD cards in the market send their responses and data non-byte-aligned. So add logic to the mmc spi driver to handle this mess. Signed-off-by: Wolfgang Muees Signed-off-by: Pierre Ossman --- drivers/mmc/host/mmc_spi.c | 150 +++++++++++++++++++++++++++++++++------------ 1 file changed, 112 insertions(+), 38 deletions(-) (limited to 'drivers/mmc/host/mmc_spi.c') diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c index ed02ebd899d..f48349d18c9 100644 --- a/drivers/mmc/host/mmc_spi.c +++ b/drivers/mmc/host/mmc_spi.c @@ -254,6 +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", @@ -271,9 +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. @@ -298,20 +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]) @@ -339,12 +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 */ @@ -725,6 +775,8 @@ mmc_spi_readblock(struct mmc_spi_host *host, struct spi_transfer *t, 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. @@ -736,38 +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) { -- cgit v1.2.3-70-g09d2