Comment 29 for bug 82680

There are a lot of conflicting reports against this bug.

1. The CONFIG_SYSFS_DEPRECATED thread is not applicable to this bug.

2. The sudo setpci -s nn:nn.n 4c.b=0x02 fix doesn't fix the underlying problem. The TI MMC card readers support two interfaces: the proprietary TI interface, and the generic "Secure Digital Host Controller Interface". Only one of these interfaces are connected to the physical pins of the MMC reader at any one time. Normally the physical pins are connected to the proprietary interface, which is supported by the broken tifm_sd driver.

The setpci command switches the physical pins to the "Secure Digital Host Controller Interface" supported by the sdhci driver. This command in effect moves the responsibility of reading/writing the MMC card to the working sdhci driver.

3. The tifm_sd driver is obviously broken. Hopefully, the patch referred to in a previous comment will fix the driver, although this is far from being definate.

I will evaluate the patch, and consider applying it to the Feisty kernel. Obviously without the necessary hardware, I am relying on one of the bug reporters to test the patch, perhaps independently, or once (if) the patch appears in a released Feisty kernel.

To confirm this analysis, it would be useful for someone to unload the tifm_sd driver (modprobe -r tifm_sd), and then to issue the setpci command. If the sdhci driver is in use, the MMC card should still be accessible.