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linuxmountsd-card

How to make the device named /dev/mmcblk0 to appear as a file in the filesystem?



I'm trying to adapt an existing SD/MMC card driver to our SD controller hardware.
I'm using Synopsys' dw_mmc code (in linux3.3) as a reference. I have a long way to go but at least it's compiled ok and the platform device and platform driver seems to have been registered.
My question is how to make the /dev/mmcblk0 file appear in the system? I named our new device ald_sd and I can see ald_sd.0 under /sys/devices/platform. under /dev, I tried 'mknod mmcblk0 179 0' and I see mmcblk0 under /dev. Then I tried 'mount /dev/mmcblk0 /mnt/sd' (after making /mnt/sd) and it gives me message 'mount: mounting /dev/mmcblk0 on /mnt/sd failed: No such device or address'.
Please help. Thank you!
Chan


Solution

  • It's been several months since I sloved this problem. long story short, when the kernel reads the super block of the SD card, then the block access is ok. usually we make /dev/sd0 using mknod command.(not mmcblock0). (mmcblock0 file is made somewhere different maybe /sys.. I don't remember). Also beware, you can mis-type mknod like mkdir or mkdev, then you can have 'No such device or address' message too. Just for your information.