On Wed, Jan 4, 2017 at 6:03 PM, Alexandre Bailon <abai...@baylibre.com> wrote:
> Sometime, a transfer may not be queued due to a race between runtime pm
> and cppi41_dma_issue_pending().
> Sometime, cppi41_runtime_resume() may be interrupted right before to
> update device PM state to RESUMED.
> When it happens, if a new dma transfer is issued, because the device is not
> in active state, the descriptor will be added to the pendding list.
> But because the descriptors in the pendding list are only queued to cppi41
> on runtime resume, the descriptor will not be queued.
> On runtime suspend, the list is not empty, which is causing a warning.
> Queue the descriptor if the device is active or resuming.
> - if (likely(pm_runtime_active(cdd->ddev.dev)))
> + active = pm_runtime_active(cdd->ddev.dev);
> + if (!active) {
> + /*
> + * Runtime resume may be interrupted before runtime_status
> + * has been updated. Test if device has resumed.
> + */
> + if (error == -EINPROGRESS) {
> + spin_lock_irqsave(&cdd->lock, flags);
> + if (list_empty(&cdd->pending))
> + active = true;
active = !!list_empty();
> + spin_unlock_irqrestore(&cdd->lock, flags);
> + }
> + }
> +
> + if (likely(active))
> push_desc_queue(c);
> else
> pending_desc(c);
--
With Best Regards,
Andy Shevchenko
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