On embedded devices, often there is a combination of removable mmc devices (e.g. MMC/SD cards) and hard wired ones (e.g. eMMC). Depending on the hardware configuration, the 'mmcblkN' node might change if the removable device is available or not at boot time.
E.g. if the removable device is attached at boot time, it might become mmxblk0. And the hard wired one mmcblk1. But if the removable device isn't there at boot time, the hard wired one will become mmcblk0. This makes it somehow difficult to hard code the root device to the non-removable device and boot fast. Signed-off-by: Heiko Schocher <h...@denx.de> --- Dirk Behme tried to bring this in, last mail I found: http://lists.infradead.org/pipermail/linux-arm-kernel/2012-July/111022.html where Dirk worked in Arnds suggestion to use the "/aliases" device node" I adapt this to the omap_hsmmc driver. Is there another solution for this problem? Or why was this patch not accepted to mainline? drivers/mmc/card/block.c | 6 ++++-- drivers/mmc/host/omap_hsmmc.c | 6 ++++++ include/linux/mmc/host.h | 3 +++ 3 files changed, 13 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index c742cfd..62250d8 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -2106,7 +2106,8 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card, struct mmc_blk_data *md; int devidx, ret; - devidx = find_first_zero_bit(dev_use, max_devices); + devidx = find_next_zero_bit(dev_use, max_devices, + card->host->devidx); if (devidx >= max_devices) return ERR_PTR(-ENOSPC); __set_bit(devidx, dev_use); @@ -2124,7 +2125,8 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card, * index anymore so we keep track of a name index. */ if (!subname) { - md->name_idx = find_first_zero_bit(name_use, max_devices); + md->name_idx = find_next_zero_bit(name_use, max_devices, + card->host->devidx); __set_bit(md->name_idx, name_use); } else md->name_idx = ((struct mmc_blk_data *) diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c index 7fb0753..0b45b48 100644 --- a/drivers/mmc/host/omap_hsmmc.c +++ b/drivers/mmc/host/omap_hsmmc.c @@ -2059,6 +2059,12 @@ static int omap_hsmmc_probe(struct platform_device *pdev) host->pbias_enabled = 0; host->vqmmc_enabled = 0; + if (pdev->dev.of_node) { + ret = of_alias_get_id(pdev->dev.of_node, "mmcblk"); + if (ret >= 0) + host->mmc->devidx = ret; + } + ret = omap_hsmmc_gpio_init(mmc, host, pdata); if (ret) goto err_gpio; diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 83b81fd..4f071681 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -382,6 +382,9 @@ struct mmc_host { int dsr_req; /* DSR value is valid */ u32 dsr; /* optional driver stage (DSR) value */ + /* preferred mmc block device index (mmcblkX) */ + unsigned int devidx; + unsigned long private[0] ____cacheline_aligned; }; -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
