Benjamin Herrenschmidt 写道: > On Sun, 2008-10-12 at 02:00 +0800, Wang Jian wrote: >> To avoid adding another rare used ata_port member, new bit is added to >> ata_port->flags. >> >> Originally, I hacked pata_platform to make it 8bit only to support 8bit >> data wired CF card. This patch is more generic. >> >> With this patch, __pata_platform_probe() interface is changed, and >> pata_of_platform is broken, so a small patch is needed. >> >> Signed-off-by: Wang Jian <lark@xxxxxxxxxxxx> >> --- > > A couple of things. First I would personally prefer (but I'm not the > libata maintainer so it's up to Jeff ...) if you had a separate patch > that adds the 8-bit support to libata core first, and then a patch that > modifies pata_platform. I will do that if my 8-bit mode patch is done right technically. > > Then, in order to avoid breaking bisection, I would like you to fixup > pata_of_platform in the same patch that modifies __pata_platform_probe > so there is no breakage in between patches. Yes. > > Now, regarding the patch itself, if the core grows a 8-bit flag, then > I strongly suspect the core should also grow the 8-bit xfer function > rather than having it hidden in pata_platform. This is the main reason I send a single RFC patch. Where to add 8-bit mode should be decided first. Because 8-bit mode is mostly used for embedded devices, my opinion is 8-bit mode in pata_platform is enough. However, look at pata_platform_data_xfer() I added, the code can be merged into ata_sff_data_xfer() of libata-sff.c easily. Moving the code there is trivial if necessary. Another problem should be addressed: using flags v.s. using data_width member. I add a bit to indicate 8 bit mode, but this seems to be a problem for future 32 bit I/O support in libata. -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
