Re: [PATCH v4 2/2] remoteproc: core: Register the character device interface

From: Bjorn Andersson <bjorn.andersson@linaro.org>
To: Siddharth Gupta <sidgup@codeaurora.org>
Cc: agross@kernel.org, ohad@wizery.com, corbet@lwn.net,
	linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-msm@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, tsoni@codeaurora.org,
	psodagud@codeaurora.org, rishabhb@codeaurora.org,
	linux-doc@vger.kernel.org
Subject: Re: [PATCH v4 2/2] remoteproc: core: Register the character device interface
Date: Thu, 16 Jul 2020 22:49:02 -0700	[thread overview]
Message-ID: <20200717054902.GJ2922385@builder.lan> (raw)
In-Reply-To: <1594148870-27276-3-git-send-email-sidgup@codeaurora.org>

On Tue 07 Jul 12:07 PDT 2020, Siddharth Gupta wrote:

> Add the character device during rproc_add. This would create
> a character device node at /dev/remoteproc<index>. Userspace
> applications can interact with the remote processor using this
> interface.
> 
> Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>
> Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
> ---
>  drivers/remoteproc/remoteproc_core.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 0f95e02..ec7fb49 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1966,6 +1966,13 @@ int rproc_add(struct rproc *rproc)
>  	struct device *dev = &rproc->dev;
>  	int ret;
>  
> +	/* add char device for this remoteproc */
> +	ret = rproc_char_device_add(rproc);
> +	if (ret) {
> +		dev_err(dev, "Failed to add char dev for %s\n", rproc->name);

Please move this error message into rproc_char_device_add(), to make it
consistent with the other error handling in this function not printing.

Apart from that it looks good.

Regards,
Bjorn

> +		return ret;
> +	}
> +
>  	ret = device_add(dev);
>  	if (ret < 0)
>  		return ret;
> @@ -2241,6 +2248,7 @@ int rproc_del(struct rproc *rproc)
>  	mutex_unlock(&rproc->lock);
>  
>  	rproc_delete_debug_dir(rproc);
> +	rproc_char_device_remove(rproc);
>  
>  	/* the rproc is downref'ed as soon as it's removed from the klist */
>  	mutex_lock(&rproc_list_mutex);
> @@ -2409,6 +2417,7 @@ static int __init remoteproc_init(void)
>  {
>  	rproc_init_sysfs();
>  	rproc_init_debugfs();
> +	rproc_init_cdev();
>  	rproc_init_panic();
>  
>  	return 0;
> @@ -2420,6 +2429,7 @@ static void __exit remoteproc_exit(void)
>  	ida_destroy(&rproc_dev_index);
>  
>  	rproc_exit_panic();
> +	rproc_exit_cdev();
>  	rproc_exit_debugfs();
>  	rproc_exit_sysfs();
>  }
> -- 
> Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
> 