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

From: Bjorn Andersson
Date: Fri Jul 17 2020 - 01:51:16 EST


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@xxxxxxxxxxxxxx>
> Signed-off-by: Siddharth Gupta <sidgup@xxxxxxxxxxxxxx>
> ---
> 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();
> }
> --
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>