Re: [PATCH v3 3/4] docs: Add documentation for user space client interface

Manivannan Sadhasivam
2020-06-19T06:39:57Z

On Thu, Jun 11, 2020 at 11:13:43AM -0700, Hemant Kumar wrote:
> MHI user space client driver is creating device file node
> for user application to perform file operations. File
> operations are handled by MHI core driver. Currently
> Loopback MHI channel is supported by this driver.
>
> Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>
> ---
> Documentation/mhi/index.rst | 1 +
> Documentation/mhi/uci.rst | 19 +++++++++++++++++++
> 2 files changed, 20 insertions(+)
> create mode 100644 Documentation/mhi/uci.rst
>
> diff --git a/Documentation/mhi/index.rst b/Documentation/mhi/index.rst
> index 1d8dec3..c75a371 100644
> --- a/Documentation/mhi/index.rst
> +++ b/Documentation/mhi/index.rst
> @@ -9,6 +9,7 @@ MHI
>
> mhi
> topology
> + uci
>
> .. only:: subproject and html
>
> diff --git a/Documentation/mhi/uci.rst b/Documentation/mhi/uci.rst
> new file mode 100644
> index 0000000..a5c5c4f
> --- /dev/null
> +++ b/Documentation/mhi/uci.rst
> @@ -0,0 +1,19 @@
> +.. SPDX-License-Identifier: GPL-2.0
> +
> +=================================
> +User space Client Interface (UCI)

Stick to 'Userspace' everywhere.

> +=================================
> +
> +UCI driver enables user space clients to communicate to external MHI devices
> +like modem and WLAN. It creates standard character device file nodes for user

UCI driver creates a single char device, isn't it?

> +space clients to perform open, read, write, pool and close file operations.
> +

poll? Btw, you need to mention explicitly how this char device can be used.
You are just mentioning standard file operations.

> +Device file node is created with format:-
> +
> +/dev/mhi_<controller_name>_<mhi_device_name>
> +
> +controller_name is the name of underlying bus used to transfer data.

underlying controller instance.

> +mhi_device_name is the name of the MHI channel being used by MHI client

What do you mean by MHI client here? Are you referring to userspace client?

> +to send or receive data using MHI protocol. MHI channels are statically
> +defined by MHI specification. Driver currently supports LOOPBACK channel
> +index 0 (Host to device) and 1 (Device to Host).

s/index/identifier

And explain a bit on how this LOOPBACK channel is getting used.

Thanks,
Mani

> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>