On Thu 08 Apr 23:39 CDT 2021, Deepak Kumar Singh wrote: [..] > +/** > + * qmp_get() - get a qmp handle from a device > + * @dev: client device pointer > + * > + * Return: handle to qmp device on success, ERR_PTR() on failure > + */ > +struct qmp *qmp_get(struct device *dev) > +{ > + struct platform_device *pdev; > + struct device_node *np; > + struct qmp *qmp; > + > + if (!dev || !dev->of_node) > + return ERR_PTR(-EINVAL); > + > + np = of_parse_phandle(dev->of_node, "qcom,qmp", 0); > + if (!np) > + return ERR_PTR(-ENODEV); > + > + pdev = of_find_device_by_node(np); > + if (!pdev) > + return ERR_PTR(-EINVAL); > + > + qmp = platform_get_drvdata(pdev); > + return qmp ? qmp : ERR_PTR(-EPROBE_DEFER); > +} > +EXPORT_SYMBOL(qmp_get); > + > +void qmp_put(struct platform_device *pdev) > +{ > + platform_device_put(pdev); I was expecting that the devres allocated struct qmp would stick around until the struct device's release callback came. As described in my answer to Mani yesterday I was wrong. As such you need to make sure that struct qmp stays around until qmp_remove() and all qmp_put() calls has been made. I presume a reasonable way to achieve this is to not use devm to allocate our struct qmp, add a kref to the object. So this would have to be a kref_put() on that instead of the platform_device_put() I asked you to implement here. Sorry about that. The rest of the patch looks good. Regards, Bjorn