From: Fabio Estevam <[email protected]> On embedded devices, there is often 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. Allow the sdhci-esdhc-imx driver to retrieve the mmc aliases, so that we can map via the device tree which mmcblk corresponds to the rootfs. Signed-off-by: Dirk Behme <[email protected]> Signed-off-by: Fabio Estevam <[email protected]> --- drivers/mmc/card/block.c | 5 +++-- drivers/mmc/host/sdhci-esdhc-imx.c | 10 +++++++++- include/linux/mmc/host.h | 2 ++ 3 files changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index 1a3163f..94f842b 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -2026,7 +2026,7 @@ 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); @@ -2044,7 +2044,8 @@ 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/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c index abc8cf0..e11a6af 100644 --- a/drivers/mmc/host/sdhci-esdhc-imx.c +++ b/drivers/mmc/host/sdhci-esdhc-imx.c @@ -524,8 +524,9 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) struct sdhci_pltfm_host *pltfm_host; struct sdhci_host *host; struct esdhc_platform_data *boarddata; - int err; + int err, ret; struct pltfm_imx_data *imx_data; + struct device_node *np = pdev->dev.of_node; host = sdhci_pltfm_init(pdev, &sdhci_esdhc_imx_pdata, 0); if (IS_ERR(host)) @@ -602,6 +603,13 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) host->mmc->parent->platform_data); } + + if (np) { + ret = of_alias_get_id(np, "mmcblk"); + if (ret >= 0) + host->mmc->devidx = ret; + } + /* write_protect */ if (boarddata->wp_type == ESDHC_WP_GPIO) { err = mmc_gpio_request_ro(host->mmc, boarddata->wp_gpio); diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 3b0c33a..8209f72 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -362,6 +362,8 @@ struct mmc_host { unsigned int slotno; /* used for sdio acpi binding */ + /* preferred mmc block device index (mmcblkX) */ + unsigned int devidx; unsigned long private[0] ____cacheline_aligned; }; -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
