Today I wanted to get my toshiba built-in SD card reader to work because I hated to have an internal reader and use an external one (shame, huh?).

So I decided to give it some tries and after many searches I discovered that this device isn’t supported in the linux kernel, so we don’t have a driver for it, but I discovered something too, This device has a built-in generic controller that moves the control into the SD-Host and we can allow this by changing a generic PCI-register value called “MMC_SD_DIS”, this register is usually configured by EEPROM and written to the laptop using the proper driver and since we don’t have a driver we will do this by hand each time the machine boots into linux, or you can put this line into /etc/rc.local

The solution is to write the following in your terminal screen as a super-user:

# setpci -s `lspci |grep “PCIxx21 Integrated”|cut -d” ” -f1` 4c=0×22

as soon as you execute this command the SD-Reader works like magic

I was really happy to get this to work and thanks for the opensource community for the free forums that helped alot