Hi Jiaxun, On 2024-05-15 02:12, Jiaxun Yang wrote: > > > 在2024年5月14日五月 下午3:50，Jonas Karlman写道： >> Hi Jiaxun, > [...] >>> + return ERR_PTR(ret); >> >> Please explain in more details what the issue this is trying to solve. >> >> Typically syscon_get_regmap() is called on a udevice returned from a >> uclass_get_device call, and that should trigger a probe for the device >> and its parents. >> >> Adding device_probe() here possible just hides an issue that exists >> somewhere else. In what instance are you ending up with a call to >> this function with a udevice that has not been probed? > > Hi Jonas, > > Thanks for the reply, my problem is in [PATCH 10/13] I'm using dev->parent > directly to get parent device and then use that pointer to access > syscon_get_regmap.
Looking at the driver model lifecycle docs and the clk_boston driver I would suggest you to change from using the of_to_plat() ops and do same in probe() ops instead. That way your parent udevice will have been probed and you do not need to manually probe it at of_to_plat() stage. https://docs.u-boot.org/en/latest/develop/driver-model/design.html#driver-lifecycle """ If your device relies on its parent setting up a suitable address space, so that dev_read_addr() works correctly, then make sure that the parent device has its setup code in of_to_plat(). If it has it in the probe method, then you cannot call dev_read_addr() from the child device's of_to_plat() method. Move it to probe() instead. """ Moving your syscon_get_regmap() call from of_to_plat() to probe() should make this syscon patch unnecessary. Regards, Jonas > > There is no chance to invoke uclass_get_device_* as what we need is just > the parent device. > > I can think of two solution without touching syscon code here. > > First would be performing uclass_get_device_by_ofnode against parent's > ofnode, which seems a little bit overkilling. > > Second would be trigger probing in dev_get_parent. > > Thanks > - Jiaxun > >> >> Also, please add a new test to test/dm/regmap.c if this solves a real >> issue. >> >> Regards, >> Jonas >> >>> priv = dev_get_uclass_priv(dev); >>> return priv->regmap; >>> } >>> >
