Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755356AbbLaI0N (ORCPT ); Thu, 31 Dec 2015 03:26:13 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:32968 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752136AbbLaI0M (ORCPT ); Thu, 31 Dec 2015 03:26:12 -0500 Subject: Re: [PATCH] soc: mediatek: PMIC wrap: Clear the vldclr if state machine is stay on FSM_VLDCLR state. To: Henry Chen References: <1450770677-13557-1-git-send-email-henryc.chen@mediatek.com> <56841C41.4040901@gmail.com> <1451527755.20140.6.camel@mtksdaap41> Cc: Sascha Hauer , linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org From: Matthias Brugger Message-ID: <5684E6A1.8050204@gmail.com> Date: Thu, 31 Dec 2015 09:26:09 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <1451527755.20140.6.camel@mtksdaap41> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3300 Lines: 99 On 31/12/15 03:09, Henry Chen wrote: > Hi Matthias, > > On Wed, 2015-12-30 at 19:02 +0100, Matthias Brugger wrote: >> >> On 22/12/15 08:51, Henry Chen wrote: >>> Sometimes PMIC is too busy to send data in time to cause pmic wrap timeout, >>> because pmic wrap is waiting for FSM_VLDCLR after finishing WACS2_CMD. It >>> just return error when issue happened, so the state machine will stay on >>> FSM_VLDCLR state when data send back later by PMIC and timeout again in next >>> time because pmic wrap waiting for FSM_IDLE state at the begining of the >>> read/write function. >>> >>> Clear the vldclr when timeout if state machine is stay on FSM_VLDCLR. >>> >>> Signed-off-by: Henry Chen >>> --- >>> drivers/soc/mediatek/mtk-pmic-wrap.c | 16 ++++++++++++++-- >>> 1 file changed, 14 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/soc/mediatek/mtk-pmic-wrap.c b/drivers/soc/mediatek/mtk-pmic-wrap.c >>> index 105597a..ccd5337 100644 >>> --- a/drivers/soc/mediatek/mtk-pmic-wrap.c >>> +++ b/drivers/soc/mediatek/mtk-pmic-wrap.c >>> @@ -443,10 +443,16 @@ static int pwrap_wait_for_state(struct pmic_wrapper *wrp, >>> static int pwrap_write(struct pmic_wrapper *wrp, u32 adr, u32 wdata) >>> { >>> int ret; >>> + u32 val; >>> >>> ret = pwrap_wait_for_state(wrp, pwrap_is_fsm_idle); >>> - if (ret) >>> + if (ret) { >>> + /* Clear vldclr bit if state is on the WACS_FSM_WFVLDCLR */ >>> + val = pwrap_readl(wrp, PWRAP_WACS2_RDATA); >>> + if (PWRAP_GET_WACS_FSM(val) == PWRAP_WACS_FSM_WFVLDCLR) >>> + pwrap_writel(wrp, 1, PWRAP_WACS2_VLDCLR); >>> return ret; >>> + } >> >> I would prefer to have this encapsulated in a (inline) function. Maybe >> with better description then just the one line comment. >> >> Thanks, >> Matthias > > Ok, I will make the description more clear, do you means write the > function like below and used it on pwrap_write/pwrap_read. > > static inline void pwrap_leave_fsm_vldclr(struct pmic_wrapper *wrp) > { > if (pwrap_is_fsm_vldclr(wrp)) > pwrap_writel(wrp, 1, PWRAP_WACS2_VLDCLR); > } > I didn't remind of pwrap_is_fsm_vldclr neither, nice. Yes please use this function and add a descriptive comment on the top, so that in the future it is clear what is happening here. Thanks, Matthias > > Thanks, > Henry > >> >>> >>> pwrap_writel(wrp, (1 << 31) | ((adr >> 1) << 16) | wdata, >>> PWRAP_WACS2_CMD); >>> @@ -457,10 +463,16 @@ static int pwrap_write(struct pmic_wrapper *wrp, u32 adr, u32 wdata) >>> static int pwrap_read(struct pmic_wrapper *wrp, u32 adr, u32 *rdata) >>> { >>> int ret; >>> + u32 val; >>> >>> ret = pwrap_wait_for_state(wrp, pwrap_is_fsm_idle); >>> - if (ret) >>> + if (ret) { >>> + /* Clear vldclr bit if state is on the WACS_FSM_WFVLDCLR */ >>> + val = pwrap_readl(wrp, PWRAP_WACS2_RDATA); >>> + if (PWRAP_GET_WACS_FSM(val) == PWRAP_WACS_FSM_WFVLDCLR) >>> + pwrap_writel(wrp, 1, PWRAP_WACS2_VLDCLR); >>> return ret; >>> + } >>> >>> pwrap_writel(wrp, (adr >> 1) << 16, PWRAP_WACS2_CMD); >>> >>> > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/