2011-06-15 04:04:49 mmc_spi and two chips on the spi bus.
Dimitar Penev (BULGARIA)
Message: 101278
Hi Guys,
I've noticed that the mmc_spi driver in 2010R1-RC5 doesn't suport two chips on the SPI bus.
I've saw that there is a pacth for this in the GIT called "move to mainline SPI locking API"
However applying it on 2010R1-RC5 seems to make our board unstable.
It seems it influence our nand flash as well somehow.
I have not investigated further, fortunately the second chip on the SPI bus is not inportant for us right now but still.
Is theer somone using mmc_spi with few chips on the same SPI bus based on 2010R1-RC5 distribution?
Thanks
Dimitar
QuoteReplyEditDelete
2011-06-15 04:50:56 Re: mmc_spi and two chips on the spi bus.
Sonic Zhang (CHINA)
Message: 101281
That patch has nothing to do with your 2010R1-RC5 release. It is against kernel mainline tree.
Don't forget to select option "SPI Bus lock" under "SPI controller driver for ADI Blackfin" in your case.
QuoteReplyEditDelete
2011-06-15 07:51:22 Re: mmc_spi and two chips on the spi bus.
Dimitar Penev (BULGARIA)
Message: 101284
Hi Sonic,
Having two SPI chips on the same bus confgured I got in the system log
mmc_spi spi0: can't share SPI bus
Based on this and what I have seen already discussed in the forum I concluded that the mmc_spi driver in the 2010R1-RC5
doesn't support SD card and another SPI chip sharing the SPI bus.
Does it mean I got confused and I will be OK if enable "SPI Bus lock".
And I don't need to patch anything?
Thanks
Dimitar
QuoteReplyEditDelete
2011-06-15 22:43:20 Re: mmc_spi and two chips on the spi bus.
Aaron Wu (CHINA)
Message: 101292
Yes, no patch needed, please enable the "SPI Bus lock" as Sonic said and share us the feedback.
QuoteReplyEditDelete
2011-06-17 06:09:03 Re: mmc_spi and two chips on the spi bus.
Dimitar Penev (BULGARIA)
Message: 101380
Hi Guys,
Thank you for the help!
Meanwhile I have noticed that I was using wrong SPI_MODE so I was reading garbage from the SD-card which the driver accepted happily.
I am curious why Linux driver doesn't confirm the CRC for the CSD data which standard defines.
Thanks
Dimitar
QuoteReplyEditDelete
2011-06-17 12:32:34 Re: mmc_spi and two chips on the spi bus.
Mike Frysinger (UNITED STATES)
Message: 101390
that'd probably be a question to post to the linux-mmc@vger.kernel.org mailing list