From mboxrd@z Thu Jan 1 00:00:00 1970 From: matthias.bgg@gmail.com (Matthias Brugger) Date: Fri, 8 Jan 2016 11:08:50 +0100 Subject: [RESEND PATCH v2] soc: mediatek: PMIC wrap: Clear the vldclr if state machine stay on FSM_VLDCLR state. In-Reply-To: References: <1451908972-11882-1-git-send-email-henryc.chen@mediatek.com> Message-ID: <568F8AB2.6080503@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 08/01/16 03:43, Ricky Liang wrote: > On Mon, Jan 4, 2016 at 8:02 PM, 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 beginning of the >> read/write function. >> >> Clear the vldclr when timeout if state machine stay on FSM_VLDCLR. >> >> Signed-off-by: Henry Chen >> --- >> Changes since v1: >> Encapsulated the code in a inline function, and add a descriptive comment. >> --- >> drivers/soc/mediatek/mtk-pmic-wrap.c | 30 ++++++++++++++++++++++++++++-- >> 1 file changed, 28 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/soc/mediatek/mtk-pmic-wrap.c b/drivers/soc/mediatek/mtk-pmic-wrap.c >> index 105597a..af919b1 100644 >> --- a/drivers/soc/mediatek/mtk-pmic-wrap.c >> +++ b/drivers/soc/mediatek/mtk-pmic-wrap.c >> @@ -412,6 +412,12 @@ static bool pwrap_is_fsm_vldclr(struct pmic_wrapper *wrp) >> return PWRAP_GET_WACS_FSM(val) == PWRAP_WACS_FSM_WFVLDCLR; >> } >> >> +static inline void pwrap_leave_fsm_vldclr(struct pmic_wrapper *wrp) >> +{ >> + if (pwrap_is_fsm_vldclr(wrp)) >> + pwrap_writel(wrp, 1, PWRAP_WACS2_VLDCLR); >> +} >> + >> static bool pwrap_is_sync_idle(struct pmic_wrapper *wrp) >> { >> return pwrap_readl(wrp, PWRAP_WACS2_RDATA) & PWRAP_STATE_SYNC_IDLE0; >> @@ -445,8 +451,18 @@ static int pwrap_write(struct pmic_wrapper *wrp, u32 adr, u32 wdata) >> int ret; >> >> ret = pwrap_wait_for_state(wrp, pwrap_is_fsm_idle); >> - if (ret) >> + if (ret) { >> + /* >> + * Timeout issue sometimes caused by the last read command >> + * failed because pmic wrap could not got the FSM_VLDCLR >> + * in time after finishing WACS2_CMD. It made state machine >> + * still on FSM_VLDCLR and timeout next time. >> + * Check the status of FSM and clear the vldclr to recovery the >> + * error. >> + */ >> + pwrap_leave_fsm_vldclr(wrp); >> return ret; >> + } >> >> pwrap_writel(wrp, (1 << 31) | ((adr >> 1) << 16) | wdata, >> PWRAP_WACS2_CMD); >> @@ -459,8 +475,18 @@ static int pwrap_read(struct pmic_wrapper *wrp, u32 adr, u32 *rdata) >> int ret; >> >> ret = pwrap_wait_for_state(wrp, pwrap_is_fsm_idle); >> - if (ret) >> + if (ret) { >> + /* >> + * Timeout issue sometimes caused by the last read command >> + * failed because pmic wrap could not got the FSM_VLDCLR >> + * in time after finishing WACS2_CMD. It made state machine >> + * still on FSM_VLDCLR and timeout next time. >> + * Check the status of FSM and clear the vldclr to recovery the >> + * error. >> + */ >> + pwrap_leave_fsm_vldclr(wrp); >> return ret; >> + } >> >> pwrap_writel(wrp, (adr >> 1) << 16, PWRAP_WACS2_CMD); >> >> -- >> 1.9.1 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> the body of a message to majordomo at vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> Please read the FAQ at http://www.tux.org/lkml/ > > > Tested-by: Ricky Liang > > On our test platform this patch fixes PMIC communication erros. > I put the comment above the function declaration. Applied to v4.5-next/soc Thanks.