在 2016/3/29 18:49, Jisheng Zhang 写道:
Hi Jaehoon, On Tue, 29 Mar 2016 19:43:34 +0900 Jaehoon Chung wrote:This patch is just RFC. I want to know opinions. Now, index of mmcblk is allocated in accordance with probing time. If want to use the mmcblk1 for some device, it can use alias. aliases { mmc0 = &mmc0; /* mmcblk0 for eMMC */ mmc1 = &mmc2; /* mmcblk1 for SD */ mmc2 = &mmc1; /* mmcblk2 for SDIO*/ };I like this feature and we do need it. In the past, we have to put emmc dt node before the sd node, but on our platform, the register base of sdhc host for emmc is higher than the one for sd, putting emmc dt node before sd looks a bit strange, but we have no better solutions.
:) That is also what I suffered currently. I have to prepare two seperate firmware with two diff fstab files to assign the mount point since sometime I need to boot from sd, but sometimes from emmc.... With this patch, I only need to dtc a new dtb... quite simple.
Thanks, JishengIf there are no corresponding values, it might be allocated with existing scheme. Signed-off-by: Jaehoon Chung <jh80.chung@xxxxxxxxxxx> --- Documentation/devicetree/bindings/mmc/mmc.txt | 11 +++++++++++ drivers/mmc/card/block.c | 17 ++++++++++++++++- 2 files changed, 27 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt b/Documentation/devicetree/bindings/mmc/mmc.txt index ed23b9b..e37ea29 100644 --- a/Documentation/devicetree/bindings/mmc/mmc.txt +++ b/Documentation/devicetree/bindings/mmc/mmc.txt @@ -71,6 +71,10 @@ Optional SDIO properties: - wakeup-source: Enables wake up of host system on SDIO IRQ assertion (Legacy property supported: "enable-sdio-wakeup") +Aliases (Optional): +- If you want to use the fixed index for block device like mmcblkX, should be +represented in the aliases node using following format "mmc(X)". +(X is an unique number for the alias.) MMC power sequences: -------------------- @@ -145,3 +149,10 @@ mmc3: mmc@01c12000 { interrupt-names = "host-wake"; }; }; + +Example with aliases nodes: + +aliases { + mmc0 = &mmc0; /* Fixed to mmcblk0 for &mmc0 */ + mmc1 = &mmc2; /* Fixed to mmcblk1 for &mmc2 */ +}; diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index 3bdbe50..6a40de5 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -35,6 +35,7 @@ #include <linux/capability.h> #include <linux/compat.h> #include <linux/pm_runtime.h> +#include <linux/of.h> #include <linux/mmc/ioctl.h> #include <linux/mmc/card.h> @@ -2190,6 +2191,7 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card, { struct mmc_blk_data *md; int devidx, ret; + int idx = 0; devidx = find_first_zero_bit(dev_use, max_devices); if (devidx >= max_devices) @@ -2209,7 +2211,20 @@ 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); + if (card->dev.parent->parent->of_node) + idx = of_alias_get_id(card->dev.parent->parent->of_node, + "mmc"); + + if (idx < 0) + md->name_idx = find_first_zero_bit(name_use, + max_devices); + else { + if (test_bit(idx, name_use)) + md->name_idx = find_first_zero_bit(name_use, + max_devices); + else + md->name_idx = (unsigned int)idx; + } __set_bit(md->name_idx, name_use); } else md->name_idx = ((struct mmc_blk_data *)
-- Best Regards Shawn Lin -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
