On 15/04/2014 at 12:26:11 +0200, Sebastian Hesselbarth wrote : > On 04/15/2014 12:00 PM, Jisheng Zhang wrote: > >On Tue, 15 Apr 2014 02:23:03 -0700 > >Sebastian Hesselbarth <sebastian.hesselbarth@xxxxxxxxx> wrote: > >>On 04/15/2014 10:07 AM, Antoine Ténart wrote: > >>>The Marvell Berlin BG2Q has 6 GPIO ports compatible with the > >>>snps,dw-apb-gpio driver. This patch add the corresponding device tree > >>>nodes. > >>> > >>>Signed-off-by: Antoine Ténart <antoine.tenart@xxxxxxxxxxxxxxxxxx> > >>>--- > >>> arch/arm/boot/dts/berlin2q.dtsi | 102 > >>>++++++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) > >>> > >>>diff --git a/arch/arm/boot/dts/berlin2q.dtsi > >>>b/arch/arm/boot/dts/berlin2q.dtsi index e6e556055dfc..b2625f896bc5 100644 > >>>--- a/arch/arm/boot/dts/berlin2q.dtsi > >>>+++ b/arch/arm/boot/dts/berlin2q.dtsi > [...] > >>>+ compatible = > >>>"snps,dw-apb-gpio-port"; > >>>+ gpio-controller; > >>>+ #gpio-cells = <2>; > >>>+ snps,nr-gpios = <32>; > >> > >>32 gpio pins for each of the 6 GPIO controllers? Either BG2Q is a GPIO > > > >Yes, BG2Q support 32 pins every port > > Wow. Thanks for confirming this! > > >>I am fine with using nr-gpios property now, but I guess BG2Q also > >>has that CONFIG[1,2] registers to actually read out the features > >>synthesized in? If I find some time, I'll prepare a patch for > >>dw-apb-gpio to exploit that (optional) information instead of > >>using nr-gpios. > > > >The problem is CONFIG1/2 registers don't exist on some versions. > >For example, the version used in BG2/BG2CD. So nr-gpio is necessary > >if we want to support these versions. > > Hmm, are you sure about BG2? I remember reading it and it contains > sane values. Anyway, a proper patch for dw-apb-gpio would include > checking for sane (e.g. non-zero) values. And nr-gpios will always > stay as fall-back just because e.g. sunxi does not have the CONFIG > registers. > Shouldn't that be use nr-gpios and if not available, read the CONFIG registers? Else, what about bogus registers ? -- Alexandre Belloni, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
