diff options
Diffstat (limited to 'drivers/mmc/host/mmc_spi.c')
| -rw-r--r-- | drivers/mmc/host/mmc_spi.c | 179 |
1 files changed, 72 insertions, 107 deletions
diff --git a/drivers/mmc/host/mmc_spi.c b/drivers/mmc/host/mmc_spi.c index d55fe4fb793..cc8d4a6099c 100644 --- a/drivers/mmc/host/mmc_spi.c +++ b/drivers/mmc/host/mmc_spi.c @@ -26,6 +26,8 @@ */ #include <linux/sched.h> #include <linux/delay.h> +#include <linux/slab.h> +#include <linux/module.h> #include <linux/bio.h> #include <linux/dma-mapping.h> #include <linux/crc7.h> @@ -34,6 +36,7 @@ #include <linux/mmc/host.h> #include <linux/mmc/mmc.h> /* for R1_SPI_* bit values */ +#include <linux/mmc/slot-gpio.h> #include <linux/spi/spi.h> #include <linux/spi/mmc_spi.h> @@ -98,7 +101,7 @@ #define r1b_timeout (HZ * 3) /* One of the critical speed parameters is the amount of data which may - * be transfered in one command. If this value is too low, the SD card + * be transferred in one command. If this value is too low, the SD card * controller has to do multiple partial block writes (argggh!). With * today (2008) SD cards there is little speed gain if we transfer more * than 64 KBytes at a time. So use this value until there is any indication @@ -181,7 +184,7 @@ mmc_spi_readbytes(struct mmc_spi_host *host, unsigned len) host->data_dma, sizeof(*host->data), DMA_FROM_DEVICE); - status = spi_sync(host->spi, &host->readback); + status = spi_sync_locked(host->spi, &host->readback); if (host->dma_dev) dma_sync_single_for_cpu(host->dma_dev, @@ -445,7 +448,6 @@ mmc_spi_command_send(struct mmc_spi_host *host, { struct scratch *data = host->data; u8 *cp = data->status; - u32 arg = cmd->arg; int status; struct spi_transfer *t; @@ -462,14 +464,12 @@ mmc_spi_command_send(struct mmc_spi_host *host, * We init the whole buffer to all-ones, which is what we need * to write while we're reading (later) response data. */ - memset(cp++, 0xff, sizeof(data->status)); + memset(cp, 0xff, sizeof(data->status)); - *cp++ = 0x40 | cmd->opcode; - *cp++ = (u8)(arg >> 24); - *cp++ = (u8)(arg >> 16); - *cp++ = (u8)(arg >> 8); - *cp++ = (u8)arg; - *cp++ = (crc7(0, &data->status[1], 5) << 1) | 0x01; + cp[1] = 0x40 | cmd->opcode; + put_unaligned_be32(cmd->arg, cp+2); + cp[6] = crc7_be(0, cp+1, 5) | 0x01; + cp += 7; /* Then, read up to 13 bytes (while writing all-ones): * - N(CR) (== 1..8) bytes of all-ones @@ -540,7 +540,7 @@ mmc_spi_command_send(struct mmc_spi_host *host, host->data_dma, sizeof(*host->data), DMA_BIDIRECTIONAL); } - status = spi_sync(host->spi, &host->m); + status = spi_sync_locked(host->spi, &host->m); if (host->dma_dev) dma_sync_single_for_cpu(host->dma_dev, @@ -684,7 +684,7 @@ mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t, host->data_dma, sizeof(*scratch), DMA_BIDIRECTIONAL); - status = spi_sync(spi, &host->m); + status = spi_sync_locked(spi, &host->m); if (status != 0) { dev_dbg(&spi->dev, "write error (%d)\n", status); @@ -708,10 +708,7 @@ mmc_spi_writeblock(struct mmc_spi_host *host, struct spi_transfer *t, * so we have to cope with this situation and check the response * bit-by-bit. Arggh!!! */ - pattern = scratch->status[0] << 24; - pattern |= scratch->status[1] << 16; - pattern |= scratch->status[2] << 8; - pattern |= scratch->status[3]; + pattern = get_unaligned_be32(scratch->status); /* First 3 bit of pattern are undefined */ pattern |= 0xE0000000; @@ -821,7 +818,7 @@ mmc_spi_readblock(struct mmc_spi_host *host, struct spi_transfer *t, DMA_FROM_DEVICE); } - status = spi_sync(spi, &host->m); + status = spi_sync_locked(spi, &host->m); if (host->dma_dev) { dma_sync_single_for_cpu(host->dma_dev, @@ -1017,7 +1014,7 @@ mmc_spi_data_do(struct mmc_spi_host *host, struct mmc_command *cmd, host->data_dma, sizeof(*scratch), DMA_BIDIRECTIONAL); - tmp = spi_sync(spi, &host->m); + tmp = spi_sync_locked(spi, &host->m); if (host->dma_dev) dma_sync_single_for_cpu(host->dma_dev, @@ -1054,6 +1051,8 @@ static void mmc_spi_request(struct mmc_host *mmc, struct mmc_request *mrq) { struct mmc_spi_host *host = mmc_priv(mmc); int status = -EINVAL; + int crc_retry = 5; + struct mmc_command stop; #ifdef DEBUG /* MMC core and layered drivers *MUST* issue SPI-aware commands */ @@ -1083,16 +1082,41 @@ static void mmc_spi_request(struct mmc_host *mmc, struct mmc_request *mrq) } #endif + /* request exclusive bus access */ + spi_bus_lock(host->spi->master); + +crc_recover: /* issue command; then optionally data and stop */ status = mmc_spi_command_send(host, mrq, mrq->cmd, mrq->data != NULL); if (status == 0 && mrq->data) { mmc_spi_data_do(host, mrq->cmd, mrq->data, mrq->data->blksz); + + /* + * The SPI bus is not always reliable for large data transfers. + * If an occasional crc error is reported by the SD device with + * data read/write over SPI, it may be recovered by repeating + * the last SD command again. The retry count is set to 5 to + * ensure the driver passes stress tests. + */ + if (mrq->data->error == -EILSEQ && crc_retry) { + stop.opcode = MMC_STOP_TRANSMISSION; + stop.arg = 0; + stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC; + status = mmc_spi_command_send(host, mrq, &stop, 0); + crc_retry--; + mrq->data->error = 0; + goto crc_recover; + } + if (mrq->stop) status = mmc_spi_command_send(host, mrq, mrq->stop, 0); else mmc_cs_off(host); } + /* release the bus */ + spi_bus_unlock(host->spi->master); + mmc_request_done(host->mmc, mrq); } @@ -1243,33 +1267,11 @@ static void mmc_spi_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) } } -static int mmc_spi_get_ro(struct mmc_host *mmc) -{ - struct mmc_spi_host *host = mmc_priv(mmc); - - if (host->pdata && host->pdata->get_ro) - return !!host->pdata->get_ro(mmc->parent); - /* - * Board doesn't support read only detection; let the mmc core - * decide what to do. - */ - return -ENOSYS; -} - -static int mmc_spi_get_cd(struct mmc_host *mmc) -{ - struct mmc_spi_host *host = mmc_priv(mmc); - - if (host->pdata && host->pdata->get_cd) - return !!host->pdata->get_cd(mmc->parent); - return -ENOSYS; -} - static const struct mmc_host_ops mmc_spi_ops = { .request = mmc_spi_request, .set_ios = mmc_spi_set_ios, - .get_ro = mmc_spi_get_ro, - .get_cd = mmc_spi_get_cd, + .get_ro = mmc_gpio_get_ro, + .get_cd = mmc_gpio_get_cd, }; @@ -1289,29 +1291,13 @@ mmc_spi_detect_irq(int irq, void *mmc) return IRQ_HANDLED; } -struct count_children { - unsigned n; - struct bus_type *bus; -}; - -static int maybe_count_child(struct device *dev, void *c) -{ - struct count_children *ccp = c; - - if (dev->bus == ccp->bus) { - if (ccp->n) - return -EBUSY; - ccp->n++; - } - return 0; -} - static int mmc_spi_probe(struct spi_device *spi) { void *ones; struct mmc_host *mmc; struct mmc_spi_host *host; int status; + bool has_ro = false; /* We rely on full duplex transfers, mostly to reduce * per-transfer overheads (by making fewer transfers). @@ -1337,32 +1323,6 @@ static int mmc_spi_probe(struct spi_device *spi) return status; } - /* We can use the bus safely iff nobody else will interfere with us. - * Most commands consist of one SPI message to issue a command, then - * several more to collect its response, then possibly more for data - * transfer. Clocking access to other devices during that period will - * corrupt the command execution. - * - * Until we have software primitives which guarantee non-interference, - * we'll aim for a hardware-level guarantee. - * - * REVISIT we can't guarantee another device won't be added later... - */ - if (spi->master->num_chipselect > 1) { - struct count_children cc; - - cc.n = 0; - cc.bus = spi->dev.bus; - status = device_for_each_child(spi->dev.parent, &cc, - maybe_count_child); - if (status < 0) { - dev_err(&spi->dev, "can't share SPI bus\n"); - return status; - } - - dev_warn(&spi->dev, "ASSUMING SPI bus stays unshared!\n"); - } - /* We need a supply of ones to transmit. This is the only time * the CPU touches these, so cache coherency isn't a concern. * @@ -1381,8 +1341,7 @@ static int mmc_spi_probe(struct spi_device *spi) mmc->ops = &mmc_spi_ops; mmc->max_blk_size = MMC_SPI_BLOCKSIZE; - mmc->max_hw_segs = MMC_SPI_BLOCKSATONCE; - mmc->max_phys_segs = MMC_SPI_BLOCKSATONCE; + mmc->max_segs = MMC_SPI_BLOCKSATONCE; mmc->max_req_size = MMC_SPI_BLOCKSATONCE * MMC_SPI_BLOCKSIZE; mmc->max_blk_count = MMC_SPI_BLOCKSATONCE; @@ -1463,18 +1422,33 @@ static int mmc_spi_probe(struct spi_device *spi) } /* pass platform capabilities, if any */ - if (host->pdata) + if (host->pdata) { mmc->caps |= host->pdata->caps; + mmc->caps2 |= host->pdata->caps2; + } status = mmc_add_host(mmc); if (status != 0) goto fail_add_host; + if (host->pdata && host->pdata->flags & MMC_SPI_USE_CD_GPIO) { + status = mmc_gpio_request_cd(mmc, host->pdata->cd_gpio, + host->pdata->cd_debounce); + if (status != 0) + goto fail_add_host; + } + + if (host->pdata && host->pdata->flags & MMC_SPI_USE_RO_GPIO) { + has_ro = true; + status = mmc_gpio_request_ro(mmc, host->pdata->ro_gpio); + if (status != 0) + goto fail_add_host; + } + dev_info(&spi->dev, "SD/MMC host %s%s%s%s%s\n", dev_name(&mmc->class_dev), host->dma_dev ? "" : ", no DMA", - (host->pdata && host->pdata->get_ro) - ? "" : ", no WP", + has_ro ? "" : ", no WP", (host->pdata && host->pdata->setpower) ? "" : ", no poweroff", (mmc->caps & MMC_CAP_NEEDS_POLL) @@ -1500,7 +1474,7 @@ nomem: } -static int __devexit mmc_spi_remove(struct spi_device *spi) +static int mmc_spi_remove(struct spi_device *spi) { struct mmc_host *mmc = dev_get_drvdata(&spi->dev); struct mmc_spi_host *host; @@ -1532,31 +1506,22 @@ static int __devexit mmc_spi_remove(struct spi_device *spi) return 0; } +static struct of_device_id mmc_spi_of_match_table[] = { + { .compatible = "mmc-spi-slot", }, + {}, +}; static struct spi_driver mmc_spi_driver = { .driver = { .name = "mmc_spi", - .bus = &spi_bus_type, .owner = THIS_MODULE, + .of_match_table = mmc_spi_of_match_table, }, .probe = mmc_spi_probe, - .remove = __devexit_p(mmc_spi_remove), + .remove = mmc_spi_remove, }; - -static int __init mmc_spi_init(void) -{ - return spi_register_driver(&mmc_spi_driver); -} -module_init(mmc_spi_init); - - -static void __exit mmc_spi_exit(void) -{ - spi_unregister_driver(&mmc_spi_driver); -} -module_exit(mmc_spi_exit); - +module_spi_driver(mmc_spi_driver); MODULE_AUTHOR("Mike Lavender, David Brownell, " "Hans-Peter Nilsson, Jan Nikitenko"); |
