From mboxrd@z Thu Jan 1 00:00:00 1970 From: matthias.bgg@gmail.com (Matthias Brugger) Date: Wed, 30 Dec 2015 19:02:41 +0100 Subject: [PATCH] soc: mediatek: PMIC wrap: Clear the vldclr if state machine is stay on FSM_VLDCLR state. In-Reply-To: <1450770677-13557-1-git-send-email-henryc.chen@mediatek.com> References: <1450770677-13557-1-git-send-email-henryc.chen@mediatek.com> Message-ID: <56841C41.4040901@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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 > > 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); > >