From mboxrd@z Thu Jan 1 00:00:00 1970 From: robh@kernel.org (Rob Herring) Date: Wed, 25 Jul 2018 11:38:23 -0600 Subject: [RFT v2 03/10] pinctrl: samsung: Document hidden requirement about one external wakeup In-Reply-To: <20180723175302.22535-4-krzk@kernel.org> References: <20180723175302.22535-1-krzk@kernel.org> <20180723175302.22535-4-krzk@kernel.org> Message-ID: <20180725173823.GA25530@rob-hp-laptop> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, Jul 23, 2018 at 07:52:55PM +0200, Krzysztof Kozlowski wrote: > Hardware (S5Pv210 and all Exynos SoCs) provides only 32 external > interrupts which can wakeup device from deep sleep modes. On S5Pv210 > these are gph0-gph3. On all Exynos designs these are gpx0-gpx3. > There is only one 32-bit register for controlling the external wakeup > interrupt mask (masking and unmasking waking capability of these > interrupts). > > This lead to implementation in pinctrl driver and machine code which was > using static memory for storing the mask value and not caring about > multiple devices of pin controller... because only one pin controller > device will be handling this. > > Since each pin controller node in Device Tree maps onto one device, this > corresponds to hidden assumption in parsing the Device Tree: external > wakeup interrupts can be defined only once. Make this assumption an > explicit requirement. > > Signed-off-by: Krzysztof Kozlowski > Cc: Tomasz Figa > Cc: Sylwester Nawrocki > Acked-by: Tomasz Figa > --- > Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) Reviewed-by: Rob Herring