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From:   Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
To:     lpieralisi@kernel.org, kw@linux.com
Cc:     kishon@kernel.org, bhelgaas@google.com, mhi@lists.linux.dev,
        linux-arm-msm@vger.kernel.org, linux-pci@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Subject: [PATCH 4/9] PCI: epf-mhi: Simulate async read/write using iATU
Date:   Mon, 27 Nov 2023 18:15:24 +0530
Message-Id: <20231127124529.78203-5-manivannan.sadhasivam@linaro.org>
In-Reply-To: <20231127124529.78203-1-manivannan.sadhasivam@linaro.org>
References: <20231127124529.78203-1-manivannan.sadhasivam@linaro.org>
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Even though iATU only supports synchronous read/write, the MHI stack may
call async read/write callbacks without knowing the limitations of the
controller driver. So in order to maintain compatibility, let's simulate
async read/write operation with iATU by invoking the completion callback
after memcpy.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/pci/endpoint/functions/pci-epf-mhi.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
index 34e7191f9508..7214f4da733b 100644
--- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
+++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
@@ -234,6 +234,9 @@ static int pci_epf_mhi_iatu_read(struct mhi_ep_cntrl *mhi_cntrl,
 
 	mutex_unlock(&epf_mhi->lock);
 
+	if (buf_info->cb)
+		buf_info->cb(buf_info);
+
 	return 0;
 }
 
@@ -262,6 +265,9 @@ static int pci_epf_mhi_iatu_write(struct mhi_ep_cntrl *mhi_cntrl,
 
 	mutex_unlock(&epf_mhi->lock);
 
+	if (buf_info->cb)
+		buf_info->cb(buf_info);
+
 	return 0;
 }
 
-- 
2.25.1