Johan Hovold <[email protected]> writes: > On Wed, Feb 20, 2019 at 11:35:06AM +0000, Mans Rullgard wrote: >> If the provided fwnode is an OF node, set dev.of_node as well. >> >> Some drivers are just shims that create extra "glue" devices with the >> DT device as parent and have the real driver bind to these. In these >> cases, the glue device needs to get a reference to the original DT node >> in order for the main driver to access properties and child nodes. >> >> For example, the sunxi-musb driver creates such a glue device using >> platform_device_register_full(). Consequently, devices attached to >> this USB interface don't get associated with DT nodes, if present, >> the way they do with EHCI. >> >> This change will allow sunxi-musb and similar driver to easily >> propagate the DT node to child devices as required. > > Just a drive-by comment, didn't look to closely at this patch, but this > all sounds familiar. > > Note that if both platform devices are bound to drivers you may end up > with some resources like pinctrl which are handled automatically by > driver core at probe time to be requested twice (and failing the second > time). > > Take a look at 4e75e1d7dac9 ("driver core: add helper to reuse a > device-tree node"), which provides a means to avoid this, and > 49484abd93ab ("USB: musb: dsps: propagate device-tree node").
Thanks, and ugh. So we should be setting the of_node_reused flag when this is the case. It's easy for the musb-dsps driver since it doesn't use platform_device_register_full() and can do this before the device_add() call. How can we convey that this flag needs to be set? >> Signed-off-by: Mans Rullgard <[email protected]> >> --- >> drivers/base/platform.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/drivers/base/platform.c b/drivers/base/platform.c >> index dff82a3c2caa..853a1d0e5845 100644 >> --- a/drivers/base/platform.c >> +++ b/drivers/base/platform.c >> @@ -512,6 +512,7 @@ struct platform_device *platform_device_register_full( >> >> pdev->dev.parent = pdevinfo->parent; >> pdev->dev.fwnode = pdevinfo->fwnode; >> + pdev->dev.of_node = of_node_get(to_of_node(pdev->dev.fwnode)); >> >> if (pdevinfo->dma_mask) { >> /* > > Johan -- Måns Rullgård
