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From:   Bhaumik Bhatt <bbhatt@codeaurora.org>
To:     manivannan.sadhasivam@linaro.org, hemantk@codeaurora.org
Cc:     linux-arm-msm@vger.kernel.org, loic.poulain@linaro.org,
        jhugo@codeaurora.org, linux-kernel@vger.kernel.org,
        Bhaumik Bhatt <bbhatt@codeaurora.org>
Subject: [PATCH v4 4/8] bus: mhi: core: Clear configuration from channel context during reset
Date:   Thu,  3 Dec 2020 17:23:13 -0800
Message-Id: <1607044997-19577-5-git-send-email-bbhatt@codeaurora.org>
In-Reply-To: <1607044997-19577-1-git-send-email-bbhatt@codeaurora.org>
References: <1607044997-19577-1-git-send-email-bbhatt@codeaurora.org>
Precedence: bulk

When clearing up the channel context after client drivers are
done using channels, the configuration is currently not being
reset entirely. Ensure this is done to appropriately handle
issues where clients unaware of the context state end up calling
functions which expect a context.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
---
 drivers/bus/mhi/core/init.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index 5cdddb2..1b6962d 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -553,6 +553,7 @@ void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl,
 	struct mhi_ring *buf_ring;
 	struct mhi_ring *tre_ring;
 	struct mhi_chan_ctxt *chan_ctxt;
+	u32 tmp;
 
 	buf_ring = &mhi_chan->buf_ring;
 	tre_ring = &mhi_chan->tre_ring;
@@ -563,7 +564,19 @@ void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl,
 	vfree(buf_ring->base);
 
 	buf_ring->base = tre_ring->base = NULL;
+	tre_ring->ctxt_wp = NULL;
 	chan_ctxt->rbase = 0;
+	chan_ctxt->rlen = 0;
+	chan_ctxt->rp = 0;
+	chan_ctxt->wp = 0;
+
+	tmp = chan_ctxt->chcfg;
+	tmp &= ~CHAN_CTX_CHSTATE_MASK;
+	tmp |= (MHI_CH_STATE_DISABLED << CHAN_CTX_CHSTATE_SHIFT);
+	chan_ctxt->chcfg = tmp;
+
+	/* Update to all cores */
+	smp_wmb();
 }
 
 int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl,
-- 
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