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Date:   Thu, 14 Dec 2023 03:49:33 +0900
From:   Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kw@linux.com>
To:     Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc:     lpieralisi@kernel.org, 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
Subject: Re: [PATCH 4/9] PCI: epf-mhi: Simulate async read/write using iATU
Message-ID: <20231213184933.GB924726@rocinante>
References: <20231127124529.78203-1-manivannan.sadhasivam@linaro.org>
 <20231127124529.78203-5-manivannan.sadhasivam@linaro.org>
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In-Reply-To: <20231127124529.78203-5-manivannan.sadhasivam@linaro.org>
Precedence: bulk

Hello,

> 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;
>  }

Looks good!

Reviewed-by: Krzysztof Wilczyński <kw@linux.com>

	Krzysztof