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Date:   Fri, 24 Jan 2020 18:47:07 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Jeffrey Hugo <jhugo@codeaurora.org>
Cc:     Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
        arnd@arndb.de, smohanad@codeaurora.org, kvalo@codeaurora.org,
        bjorn.andersson@linaro.org, hemantk@codeaurora.org,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 02/16] bus: mhi: core: Add support for registering MHI
 controllers
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References: <20200123111836.7414-1-manivannan.sadhasivam@linaro.org>
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 <20200124082939.GA2921617@kroah.com>
 <42c79181-9d97-3542-c6b0-1e37f9b2ff39@codeaurora.org>
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On Fri, Jan 24, 2020 at 07:24:43AM -0700, Jeffrey Hugo wrote:
> > > +/**
> > > + * struct mhi_result - Completed buffer information
> > > + * @buf_addr: Address of data buffer
> > > + * @dir: Channel direction
> > > + * @bytes_xfer: # of bytes transferred
> > > + * @transaction_status: Status of last transaction
> > > + */
> > > +struct mhi_result {
> > > +	void *buf_addr;
> > 
> > Why void *?
> 
> Because its not possible to resolve this more clearly.  The client provides
> the buffer and knows what the structure is.  The bus does not. Its just an
> opaque pointer (hence void *) to the bus, and the client needs to decode it.
> This is the struct that is handed to the client to allow them to decode the
> activity (either a received buf, or a confirmation that a transmitted buf
> has been consumed).

Then shouldn't this be a "u8 *" instead as you are saying how many bytes
are here?

thanks,

greg k-h