From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Boyd Subject: Re: [PATCH V2] spmi: pmic-arb: Enforce the ownership check optionally Date: Wed, 30 Aug 2017 14:02:03 -0700 Message-ID: <20170830210203.GS21656@codeaurora.org> References: <1503070110-15018-1-git-send-email-kgunda@codeaurora.org> <20170822085541.GB3685@dragon> <20170822203132.GC21656@codeaurora.org> <20170824121818.GE3685@dragon> <20170824183701.GN21656@codeaurora.org> <20170825074324.GF3685@dragon> <20170825231818.GP21656@codeaurora.org> <20170826034636.GG3685@dragon> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20170826034636.GG3685@dragon> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Shawn Guo Cc: Kiran Gunda , gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org, Rob Herring , Mark Rutland , Abhijeet Dharmapurikar , David Collins , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-msm-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-arm-msm@vger.kernel.org On 08/26, Shawn Guo wrote: > On Fri, Aug 25, 2017 at 04:18:18PM -0700, Stephen Boyd wrote: > > > > Right. Does the GPIO work? If so, it sounds like the read/write > > access checks in spmi pmic arb don't work properly. > > The check works. With the check in there, PM8916 GPIO doesn't work. > However, the consequence is that not only user3 but all GPIO leds under > 'leds' node will fail to register, because any GPIO led's failing on > create_gpio_led() makes leds-gpio driver probe fail as a while. That's > how leds-gpio driver works. > > Also, per schematics, PM8916 GPIO1 is indeed routed to user3 LED on > db410c board. Why do you think apq8016-sbc device tree shouldn't use > the GPIO for that at all? Isn't it firmware's fault that the ownership > of the peripheral is not properly configured? If the ownership was not properly configured in the firmware, then I imagine it would mean that we can't control the GPIO for the LED. But that doesn't seem to be true. I can see on my board that I get impermissible write failures on the GPIO when controlling the GPIO brightness, but it doesn't actually matter because the led still lights up. So the checks for write/read permission seem incorrect, or they're not being enforced. Anyway, I just wanted to make sure the GPIO still works, and it looks like it does, so removing the permission checks is enough to make me happy. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751456AbdH3VCK (ORCPT ); Wed, 30 Aug 2017 17:02:10 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:43544 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750814AbdH3VCI (ORCPT ); Wed, 30 Aug 2017 17:02:08 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 493B960858 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=sboyd@codeaurora.org Date: Wed, 30 Aug 2017 14:02:03 -0700 From: Stephen Boyd To: Shawn Guo Cc: Kiran Gunda , gregkh@linuxfoundation.org, Rob Herring , Mark Rutland , Abhijeet Dharmapurikar , David Collins , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-msm-owner@vger.kernel.org Subject: Re: [PATCH V2] spmi: pmic-arb: Enforce the ownership check optionally Message-ID: <20170830210203.GS21656@codeaurora.org> References: <1503070110-15018-1-git-send-email-kgunda@codeaurora.org> <20170822085541.GB3685@dragon> <20170822203132.GC21656@codeaurora.org> <20170824121818.GE3685@dragon> <20170824183701.GN21656@codeaurora.org> <20170825074324.GF3685@dragon> <20170825231818.GP21656@codeaurora.org> <20170826034636.GG3685@dragon> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170826034636.GG3685@dragon> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/26, Shawn Guo wrote: > On Fri, Aug 25, 2017 at 04:18:18PM -0700, Stephen Boyd wrote: > > > > Right. Does the GPIO work? If so, it sounds like the read/write > > access checks in spmi pmic arb don't work properly. > > The check works. With the check in there, PM8916 GPIO doesn't work. > However, the consequence is that not only user3 but all GPIO leds under > 'leds' node will fail to register, because any GPIO led's failing on > create_gpio_led() makes leds-gpio driver probe fail as a while. That's > how leds-gpio driver works. > > Also, per schematics, PM8916 GPIO1 is indeed routed to user3 LED on > db410c board. Why do you think apq8016-sbc device tree shouldn't use > the GPIO for that at all? Isn't it firmware's fault that the ownership > of the peripheral is not properly configured? If the ownership was not properly configured in the firmware, then I imagine it would mean that we can't control the GPIO for the LED. But that doesn't seem to be true. I can see on my board that I get impermissible write failures on the GPIO when controlling the GPIO brightness, but it doesn't actually matter because the led still lights up. So the checks for write/read permission seem incorrect, or they're not being enforced. Anyway, I just wanted to make sure the GPIO still works, and it looks like it does, so removing the permission checks is enough to make me happy. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project