From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH 3/3] [v5] pinctrl: qcom: qdf2xxx: add support for new ACPI HID QCOM8002 Date: Wed, 13 Dec 2017 16:43:05 +0200 Message-ID: <1513176185.7000.22.camel@linux.intel.com> References: <1513111858-6251-1-git-send-email-timur@codeaurora.org> <1513111858-6251-4-git-send-email-timur@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1513111858-6251-4-git-send-email-timur@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org To: Timur Tabi , linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org, Linus Walleij , Mika Westerberg , thierry.reding@gmail.com, Stephen Boyd , david.brown@linaro.org, andy.gross@linaro.org, Bjorn Andersson , Varadarajan Narayanan , Archit Taneja List-Id: linux-gpio@vger.kernel.org On Tue, 2017-12-12 at 14:50 -0600, Timur Tabi wrote: > Newer versions of the firmware for the Qualcomm Datacenter > Technologies > QDF2400 restricts access to a subset of the GPIOs on the TLMM. To > prevent older kernels from accidentally accessing the restricted > GPIOs, > we change the ACPI HID for the TLMM block from QCOM8001 to QCOM8002, > and introduce a new property "gpios". This property is an array of > specific GPIOs that are accessible. When an older kernel boots on > newer (restricted) firmware, it will fail to probe. > > To implement the sparse GPIO map, we register all of the GPIOs, but > set > the pin count for the unavailable GPIOs to zero. The pinctrl-msm > driver will block those unavailable GPIOs from being accessed. > > To allow newer kernels to support older firmware, the driver retains > support for QCOM8001. Please, read my comments to v8, same applies here. -- Andy Shevchenko Intel Finland Oy