From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nishanth Menon Subject: Re: [PATCH v2] pinctrl: dra: dt-bindings: Fix output pull up/down Date: Mon, 3 Nov 2014 08:59:36 -0600 Message-ID: <54579858.4030605@ti.com> References: <1414752745-13696-1-git-send-email-rogerq@ti.com> <1415009392-6627-1-git-send-email-rogerq@ti.com> <20141103143023.GA8260@kahuna> <545794CB.5030802@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <545794CB.5030802@ti.com> Sender: linux-omap-owner@vger.kernel.org To: Roger Quadros Cc: tony@atomide.com, balbi@ti.com, linux-omap@vger.kernel.org, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org On 11/03/2014 08:44 AM, Roger Quadros wrote: > On 11/03/2014 04:30 PM, Nishanth Menon wrote: >> On 12:09-20141103, Roger Quadros wrote: >>> For PIN_OUTPUT_PULLUP and PIN_OUTPUT_PULLDOWN we must not set the >>> PULL_DIS bit which disables the PULLs. >>> >>> PULL_ENA is a 0 and using it in an OR operation is a NOP, so don't >>> use it in the PIN_OUTPUT_PULLUP/DOWN macros. >>> >>> Fixes: 23d9cec07c58 ("pinctrl: dra: dt-bindings: Fix pull enable/disable") >>> >>> Signed-off-by: Roger Quadros >>> --- >>> include/dt-bindings/pinctrl/dra.h | 4 ++-- >>> 1 file changed, 2 insertions(+), 2 deletions(-) >>> >>> diff --git a/include/dt-bindings/pinctrl/dra.h b/include/dt-bindings/pinctrl/dra.h >>> index 3d33794..7448edf 100644 >>> --- a/include/dt-bindings/pinctrl/dra.h >>> +++ b/include/dt-bindings/pinctrl/dra.h >>> @@ -40,8 +40,8 @@ >>> >>> /* Active pin states */ >>> #define PIN_OUTPUT (0 | PULL_DIS) >>> -#define PIN_OUTPUT_PULLUP (PIN_OUTPUT | PULL_ENA | PULL_UP) >>> -#define PIN_OUTPUT_PULLDOWN (PIN_OUTPUT | PULL_ENA) >>> +#define PIN_OUTPUT_PULLUP (PULL_UP) >>> +#define PIN_OUTPUT_PULLDOWN (0) >>> #define PIN_INPUT (INPUT_EN | PULL_DIS) >>> #define PIN_INPUT_SLEW (INPUT_EN | SLEWCONTROL) >>> #define PIN_INPUT_PULLUP (PULL_ENA | INPUT_EN | PULL_UP) >> >> You are right, we do have an issue with using PIN_OUTPUT along with >> remaining setting. >> >> For a moment, I wondered why input was not impacted - then I realized >> that INPUT_EN was being used instead of PIN_INPUT - following that >> convention. With the intent being explicitly using macros that >> clearly indicate what each setting combination is is, how about the >> following? >> >> >> diff --git a/include/dt-bindings/pinctrl/dra.h b/include/dt-bindings/pinctrl/dra.h >> index 3d33794..d4037e7 100644 >> --- a/include/dt-bindings/pinctrl/dra.h >> +++ b/include/dt-bindings/pinctrl/dra.h >> @@ -34,14 +34,15 @@ >> #define PULL_DIS (1 << 16) >> #define PULL_UP (1 << 17) >> #define INPUT_EN (1 << 18) >> +#define OUTPUT_EN (0 << 18) >> #define SLEWCONTROL (1 << 19) >> #define WAKEUP_EN (1 << 24) >> #define WAKEUP_EVENT (1 << 25) >> >> /* Active pin states */ >> -#define PIN_OUTPUT (0 | PULL_DIS) >> -#define PIN_OUTPUT_PULLUP (PIN_OUTPUT | PULL_ENA | PULL_UP) >> -#define PIN_OUTPUT_PULLDOWN (PIN_OUTPUT | PULL_ENA) >> +#define PIN_OUTPUT (OUTPUT_EN | PULL_DIS) >> +#define PIN_OUTPUT_PULLUP (OUTPUT_EN | PULL_ENA | PULL_UP) >> +#define PIN_OUTPUT_PULLDOWN (OUTPUT_EN | PULL_ENA) > > To me it adds more confusion and this change is a NOP as we're ORing 0 here > with OUTPUT_EN. look at this this way: PIN_OUTPUT_PULLDOWN (OUTPUT_EN | PULL_ENA) should probably trigger in mind (what about PULLDOWN?) PIN_OUTPUT_PULLDOWN (OUTPUT_EN | PULL_ENA | PULL_DOWN) then verify values of each OUTPUT_EN -> 0 in bit 18, ok, etc. if we ensure that PIN_XX macros use just the basic primitives, it is easier to prevent the mistake like the one I made. the other option of not defining macros whose values are 0 implies that the reviewer has to recheck against trm to ensure all the right "1" bits are set. just my view here. > >> #define PIN_INPUT (INPUT_EN | PULL_DIS) >> #define PIN_INPUT_SLEW (INPUT_EN | SLEWCONTROL) >> #define PIN_INPUT_PULLUP (PULL_ENA | INPUT_EN | PULL_UP) >> > > cheers, > -roger > -- Regards, Nishanth Menon