Hi,

I have just tested kernel 2.6.24-rc1 with SD/MMC through SPI bus on the
AT91SAM9261EK board (SPI NPCS3) and noted that the SD card was detected and
info were noted under "/sys/bus/mmc" directory.

However, no device, such as mmcblk0p1, was assigned at all.

I have 2 questions with regards to SD/MMC over SPI.

1) In the code, I have commented out all other SPI devices on SPI0 bus
except for the SD card at spi0.3. However, I got an error "can't share SPI
bus". Anyone can advise what is the reason behind this error ?
(In order to proceed with my test below, I temporary got over this issue by
commenting out the check that gives this error.)

2) The kernel 2.6.24-rc1 boots up and detected the SD card with the console
output "new SD card on SPI". However, no device name, such as mmcblk0p1,
were allocated. In addition, I noted the following messages before the
sentence "mmc0: new SD card on SPI".

****** extract from console output ***********
WARNING: at drivers/mmc/core/core.c:397 mmc_set_clock()
[<c002901c>] (dump_stack+0x0/0x14) from [<c018dfd8>]
(mmc_set_clock+0x40/0xb4)
[<c018df98>] (mmc_set_clock+0x0/0xb4) from [<c01907b4>]
(mmc_attach_sd+0x610/0x844)
[<c01901a4>] (mmc_attach_sd+0x0/0x844) from [<c018e3e4>]
(mmc_rescan+0x204/0x2e0)
[<c018e1e0>] (mmc_rescan+0x0/0x2e0) from [<c004b154>]
(run_workqueue+0xb8/0x148)
 r7:00000000 r6:c018e1e0 r5:c044e000 r4:c048d4a0
[<c004b09c>] (run_workqueue+0x0/0x148) from [<c004bbe4>]
(worker_thread+0xa8/0xbc)
 r6:c004bb3c r5:c048d4a0 r4:c048d4a8
[<c004bb3c>] (worker_thread+0x0/0xbc) from [<c004f5f4>] (kthread+0x58/0x90)
 r5:c048d4a0 r4:c044e000
[<c004f59c>] (kthread+0x0/0x90) from [<c003e698>] (do_exit+0x0/0x6fc)
 r6:00000000 r5:00000000 r4:00000000
****** end of extract ***********

(I have attached a console debug output, including dmesg output, as well)

FYI, I am using a blank 16MB SD card with FAT filesystem.

Appreciate any advices/help given.

Lastly, I would like to know if the SD/MMC over SPI can be shared with other
SPI devices, such as touchscreen controller ADS7843 (purposely left out in
the current code) ?

Thanks in advance.