shell cmd msdosfmt a NOOP (in 4.9.1) for SD/MMC
chrisj at rtems.org
Sat Jan 24 00:01:15 UTC 2009
Gene Smith wrote:
> I tried the shell command msdosfmt again on my MMC and still nothing
> happens. I thought I had all my drivers working OK. It gets to the point
> in the format code where it wants to write a block to flash but the
> "write_entry" for the driver is NULL so nothing happens. However, no
> error is flagged so the shell still prints "formatting successful."
> The write_entry is the NULL entry for sd_card_disk_ops in spi-sd-card.c.
> When I change it from NULL and set it to sd_card_driver_write (a
> function in the same file that I had never seen called) msdosfmt
> attempts to do the write of the block with this function.
> However, it still fails inside sd_card_driver_write(). I think because
> the driver table "e" that it gets with the call to
> sd_card_driver_get_entry() is bad since the "major number" is 8 (a 2nd
> instance) instead of "major number" 9 (the first instance with the flash
> info set correctly). This kludge fixes it inside 4.9.1's
> /* Get driver entry */
> #if 0
> rv = sd_card_driver_get_entry(minor, &e);
> CHECK_RVSC( rv, "Get driver entry");
> e = &sd_card_driver_table;
> /* Start */
> sc = sd_card_start(e); <---this failed with #if 0 code!
> I made the same change in sd_card_driver_read(), not sure if it is called.
> Looking at the HEAD version of spi-sd-card.c, I see it has been changed
> so that there would only be a single "major" instance generated per bus
> device (in my case one SPI device). Also functions
> sd_card_driver_write/read() are removed from HEAD. However, the
> "write_entry" function is now rtems_blkdev_generic_write (not defined in
> 4.9.1). Hopefully the correct function will be called when msdosfmt code
> calls rtems_blkdev_generic_write().
Maybe these threads will help explain what has changed:
Given what you say I suspect the CVS version will format the card.
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