On Wed 13 Nov 00:52 PST 2019, Fabien Dessenne wrote:
> If the rproc driver is probed before the mailbox driver and if the rproc
> Device Tree node has some mailbox properties, the rproc driver probe
> shall be deferred instead of being probed without mailbox support.
>
> Signed-off-by: Fabien Dessenne <fabien.dessenne@xxxxxx>
> ---
> Changes since v2: free other requested mailboxes after one request fails
> Changes since v1: test IS_ERR() before checking PTR_ERR()
> ---
> drivers/remoteproc/stm32_rproc.c | 12 ++++++++++--
> 1 file changed, 10 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c
> index 2cf4b29..4b67480 100644
> --- a/drivers/remoteproc/stm32_rproc.c
> +++ b/drivers/remoteproc/stm32_rproc.c
> @@ -310,7 +310,7 @@ static const struct stm32_mbox stm32_rproc_mbox[MBOX_NB_MBX] = {
> }
> };
>
> -static void stm32_rproc_request_mbox(struct rproc *rproc)
> +static int stm32_rproc_request_mbox(struct rproc *rproc)
> {
> struct stm32_rproc *ddata = rproc->priv;
> struct device *dev = &rproc->dev;
> @@ -329,10 +329,16 @@ static void stm32_rproc_request_mbox(struct rproc *rproc)
>
> ddata->mb[i].chan = mbox_request_channel_byname(cl, name);
> if (IS_ERR(ddata->mb[i].chan)) {
> + if (PTR_ERR(ddata->mb[i].chan) == -EPROBE_DEFER) {
> + ddata->mb[i].chan = NULL;
So this relies on the caller jumping to stm32_rproc_free_mbox() to
release a subset of ddata->mb[x].chan. While this works I find it error
prone and would prefer the idiomatic solution of cleaning things up, in
this function, before returning.
So, could you please goto a snippet that loops backwards from i-- to 0
calling mbox_free_channel() and then return -EPROBE_DEFER instead?
Thanks,
Bjorn
> + return -EPROBE_DEFER;
> + }
> dev_warn(dev, "cannot get %s mbox\n", name);
> ddata->mb[i].chan = NULL;
> }
> }
> +
> + return 0;
> }
>
> static int stm32_rproc_set_hold_boot(struct rproc *rproc, bool hold)
> @@ -596,7 +602,9 @@ static int stm32_rproc_probe(struct platform_device *pdev)
> if (ret)
> goto free_rproc;
>
> - stm32_rproc_request_mbox(rproc);
> + ret = stm32_rproc_request_mbox(rproc);
> + if (ret)
> + goto free_mb;
>
> ret = rproc_add(rproc);
> if (ret)
> --
> 2.7.4
>
