| Message ID | 1432570172-86963-4-git-send-email-andriy.shevchenko@linux.intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
On Mon, 25 May 2015, Andy Shevchenko wrote: > From: Heikki Krogerus <heikki.krogerus@linux.intel.com> > > If the parent is still suspended when a driver probe, > remove or shutdown is attempted, the result may be a > failure. > > For example, if the parent is a PCI MFD device that has been > suspended when we try to probe our device, any register > reads will return 0xffffffff. > > To fix the problem, making sure the parent is always awake > before using driver probe, remove or shutdown. > > Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > --- > drivers/base/platform.c | 21 ++++++++++++++++++++- Why make the changes here rather than in dd.c? Is there something special about platform devices? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, May 25, 2015 at 01:36:43PM -0400, Alan Stern wrote: > On Mon, 25 May 2015, Andy Shevchenko wrote: > > > From: Heikki Krogerus <heikki.krogerus@linux.intel.com> > > > > If the parent is still suspended when a driver probe, > > remove or shutdown is attempted, the result may be a > > failure. > > > > For example, if the parent is a PCI MFD device that has been > > suspended when we try to probe our device, any register > > reads will return 0xffffffff. > > > > To fix the problem, making sure the parent is always awake > > before using driver probe, remove or shutdown. > > > > Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > --- > > drivers/base/platform.c | 21 ++++++++++++++++++++- > > Why make the changes here rather than in dd.c? Is there something > special about platform devices? There isn't. That would definitely be better. Thanks Alan,
diff --git a/drivers/base/platform.c b/drivers/base/platform.c index ebf034b..59fcda5 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -518,9 +518,15 @@ static int platform_drv_probe(struct device *_dev) ret = dev_pm_domain_attach(_dev, true); if (ret != -EPROBE_DEFER) { + if (_dev->parent != &platform_bus) + pm_runtime_get_sync(_dev->parent); + ret = drv->probe(dev); if (ret) dev_pm_domain_detach(_dev, true); + + if (_dev->parent != &platform_bus) + pm_runtime_put(_dev->parent); } if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) { @@ -542,9 +548,15 @@ static int platform_drv_remove(struct device *_dev) struct platform_device *dev = to_platform_device(_dev); int ret; + if (_dev->parent != &platform_bus) + pm_runtime_get_sync(_dev->parent); + ret = drv->remove(dev); - dev_pm_domain_detach(_dev, true); + if (_dev->parent != &platform_bus) + pm_runtime_put(_dev->parent); + + dev_pm_domain_detach(_dev, true); return ret; } @@ -553,7 +565,14 @@ static void platform_drv_shutdown(struct device *_dev) struct platform_driver *drv = to_platform_driver(_dev->driver); struct platform_device *dev = to_platform_device(_dev); + if (_dev->parent != &platform_bus) + pm_runtime_get_sync(_dev->parent); + drv->shutdown(dev); + + if (_dev->parent != &platform_bus) + pm_runtime_put(_dev->parent); + dev_pm_domain_detach(_dev, true); }