[U-Boot] [PATCH v5 20/23] spi: mxs_spi: Use GENMASK

[Marek Vasut <marex@denx.de>]

On Saturday, October 24, 2015 at 11:49:43 PM, Tom Rini wrote:
> On Sat, Oct 24, 2015 at 03:48:14PM +0200, Marek Vasut wrote:
> > On Saturday, October 24, 2015 at 03:42:43 PM, Jagan Teki wrote:
> > > On 24 October 2015 at 18:10, Marek Vasut <marex@denx.de> wrote:
> > > > On Saturday, October 24, 2015 at 05:39:07 AM, Jagan Teki wrote:
> > > >> Replace numeric mask hexcodes with GENMASK macro
> > > >> in mxs_spi
> > > >> 
> > > >> Cc: Marek Vasut <marex@denx.de>
> > > >> Signed-off-by: Jagan Teki <jteki@openedev.com>
> > > >> ---
> > > >> 
> > > >>  drivers/spi/mxs_spi.c | 2 +-
> > > >>  1 file changed, 1 insertion(+), 1 deletion(-)
> > > >> 
> > > >> diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c
> > > >> index 627644b..459c603 100644
> > > >> --- a/drivers/spi/mxs_spi.c
> > > >> +++ b/drivers/spi/mxs_spi.c
> > > >> @@ -23,7 +23,7 @@
> > > >> 
> > > >>  #define      MXS_SPI_MAX_TIMEOUT     1000000
> > > >>  #define      MXS_SPI_PORT_OFFSET     0x2000
> > > >> 
> > > >> -#define MXS_SSP_CHIPSELECT_MASK              0x00300000
> > > >> +#define MXS_SSP_CHIPSELECT_MASK              GENMASK(21, 20)
> > > >> 
> > > >>  #define MXS_SSP_CHIPSELECT_SHIFT     20
> > > > 
> > > > This is just making things unreadable, please keep it as is. NAK.
> > > 
> > > What's wrong with the GENMASK here is that something that you against
> > > with it? It don't look like unreadable.
> > 
> > If I open the datasheet, I can easily locate mask 0x0030_0000 and figure
> > out which bits I need to work with. With genmask ... not so much. It only
> > obfuscates the code.
> 
> Really?  I don't have the "mxs" datasheet handy but I have the mx6
> solo/duallite one handy and the SPI chapter talks about bits and has
> them broken down that way, not the hex numbers for masking whatever
> field.  This matched my expectation on how I recall the TI parts being
> as well, bit field descriptions and binary values, not hex.

MXS is sigmatel design, so the datasheets are different. And I am much more
fond of a bitmask being a bitmask (or a hex number) than some ad-hoc macro.

Best regards,
Marek Vasut