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From:   Maulik Shah <mkshah@codeaurora.org>
To:     bjorn.andersson@linaro.org, agross@kernel.org
Cc:     linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        dianders@chromium.org, ilina@codeaurora.org, lsrao@codeaurora.org,
        Maulik Shah <mkshah@codeaurora.org>
Subject: [PATCH] drivers: qcom: rpmh-rsc: Do not read back the register write on trigger
Date:   Tue, 24 Nov 2020 15:23:30 +0530
Message-Id: <1606211610-15168-1-git-send-email-mkshah@codeaurora.org>
Precedence: bulk

From: Lina Iyer <ilina@codeaurora.org>

When triggering a TCS to send its contents, reading back the trigger
value may return an incorrect value. That is because, writing the
trigger may raise an interrupt which could be handled immediately and
the trigger value could be reset in the interrupt handler.

A write_tcs_reg_sync() would read back the value that is written and try
to match it to the value written to ensure that the value is written,
but if that value is different, we may see false error for same.

Signed-off-by: Lina Iyer <ilina@codeaurora.org>
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
---
 drivers/soc/qcom/rpmh-rsc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c
index 37969dc..0b082ec 100644
--- a/drivers/soc/qcom/rpmh-rsc.c
+++ b/drivers/soc/qcom/rpmh-rsc.c
@@ -364,7 +364,7 @@ static void __tcs_set_trigger(struct rsc_drv *drv, int tcs_id, bool trigger)
 		enable = TCS_AMC_MODE_ENABLE;
 		write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
 		enable |= TCS_AMC_MODE_TRIGGER;
-		write_tcs_reg_sync(drv, RSC_DRV_CONTROL, tcs_id, enable);
+		write_tcs_reg(drv, RSC_DRV_CONTROL, tcs_id, enable);
 	}
 }
 
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