[U-Boot] [PATCH] spi: tegra20: fix mode selection logic

[Mirza Krak]

2016-08-12 23:06 GMT+02:00 Stephen Warren <swarren at wwwdotorg.org>:
> From: Stephen Warren <swarren at nvidia.com>
>
> When the set_mode() function runs, the SPI bus is not active, and hence
> the clocks to the SPI controller are not running. Any register read/write
> at this time will hang the CPU. Remove the code from set_mode() that does
> this, and move it to the correct place in claim_bus().
>
> This essentially reverts and re-implements the patch mentioned in the
> fixes tag below. I'm not sure how the original could ever have worked on
> any Tegra platform; it certainly breaks the only Tegra board I have that
> uses SPI.

Hi Stephen.

This has most definitely worked for me on both Tegra2 (colibri_t20)
and Tegra3(colibri_t30). Though I am using a 2015.04 u-boot which was
the release when I wrote this patch, and I haven't actually tried any
later releases. Something happened along the way that "broke" it?

>
> Fixes: 5cb1b7b395c0 ("spi: tegra20: Add support for mode selection")
> Cc: Mirza Krak <mirza.krak at hostmobility.com>
> Signed-off-by: Stephen Warren <swarren at nvidia.com>
> ---
> As far as I can tell, the fixed patch was never CC'd to any Tegra
> maintainer:-(

This patch was one of my first contributions to an open-source project
and I might have missed a few steps, like CC the Tegra maintainers.

I know better now, sorry for any inconvenience caused by this.

-- 
Med Vänliga Hälsningar / Best Regards

*******************************************************************
Mirza Krak
Host Mobility AB
mirza.krak at hostmobility.com
Anders Personsgatan 12, 416 64 Göteborg
Sweden
http://www.hostmobility.com
Direct: +46 31 31 32 704
Phone: +46 31 31 32 700
Fax: +46 31 80 67 51
Mobile: +46 730 28 06 22
*******************************************************************