On Monday, August 04, 2014 at 02:48:54 PM, Nikita Kiryanov wrote: > Hi Marek, > > On 03/08/14 16:46, Marek Vasut wrote: > > On Sunday, August 03, 2014 at 09:34:33 AM, Nikita Kiryanov wrote: > >> MXC SPI driver has a feature whereas a GPIO line can be used as a CS > >> signal. This is set up by joining the CS and GPIO values into a single > >> value using (cs | gpio << 8), and passing it off as a CS value. This > >> breaks the sf probe command, because it is no longer possible to invoke > >> it as sf probe <cs>. Instead, the user must use sf probe <cs | gpio << > >> 8>. > >> > >> Fix this by introducing a new board function: board_spi_cs_gpio(). > >> When called, board_spi_cs_gpio() will return the gpio number for the > >> cs value it is given. > >> > >> Cc: Jagannadha Sutradharudu Teki <[email protected]> > >> Cc: Eric Nelson <[email protected]> > >> Cc: Eric Benard <[email protected]> > >> Cc: Fabio Estevam <[email protected]> > >> Cc: Tim Harvey <[email protected]> > >> Cc: Stefano Babic <[email protected]> > >> Cc: Tom Rini <[email protected]> > >> Signed-off-by: Nikita Kiryanov <[email protected]> > > > > Just curious, but is this fixing generic SF code or MXC SPI driver ? I'd > > think the later, but it's not obvious from neither the description nor > > the subject. I don't quite understand the problem that you're trying to > > fix either, what happened, did the user command interface change ? > > The U-Boot shell command "sf probe" can accept a chip select value, but > if the SPI device on the other end requires an active chip-select over > multiple transactions (achieved in the MXC SPI driver using a GPIO), > simply typing something like "sf probe 0" will not work.
Why not ? > This is because whatever the user passes as chip select is propagated > to the driver, and the driver expects this value to have GPIO > information. So for example, if IMX_GPIO_NR(2, 30) is used to force > active chip select 0, then instead of "sf probe 0" the user will have > to type "sf probe 15872". You mean sf probe 0:15872 , right ? But then, you can use CONFIG_DEFAULT_SPI_CS to specify the default CS, no ? > I agree that the subject line should be made a bit more specific > to mxc_spi though... > > > [...] > > Best regards, > > Marek Vasut Best regards, Marek Vasut _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
