Hi Kishon, On Tue, Jun 15, 2021 at 08:31:48PM +0530, Kishon Vijay Abraham I wrote: > Hi Manivannan, > > On 15/06/21 7:07 pm, Manivannan Sadhasivam wrote: > > Add support for passing the custom notifications between the endpoint > > controller and the function driver. This helps in passing the > > notifications that are more specific to the controller and corresponding > > function driver. The opaque `data` arugument in pci_epc_custom_notify() > > function can be used to carry the event specific data that helps in > > differentiating the events. > > > > For instance, the Qcom EPC device generates specific events such as > > MHI_A7, BME, DSTATE_CHANGE, PM_TURNOFF etc... These events needs to be > > passed to the function driver for proper handling. Hence, this custom > > notifier can be used to pass these events. > > Bus master enable and PME events sounds generic events and not QCOM > specific. Yes, that's correct! I thought about adding the notifiers for them but not sure about the convetion in EP stack. So went with an opaque notifier but I don't have any issue in adding them. > Also this patch should be sent along with how it's going to be > used in function driver. > The function driver which is going to use this notifier is under development but I can share a snippet if that helps. > In general my preference would be to add only well defined notifiers > given that the endpoint function drivers are generic. > Not all functions are generic ones. For example, on Qcom modems there is a MHI function driver which transports the IP packets to the host and talks to the MHI host stack[1]. So for sure we need to have a custom notifier for vendor specific events. Thanks, Mani [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/bus/mhi > Thanks > Kishon > > > > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> > > --- > > drivers/pci/endpoint/pci-epc-core.c | 19 +++++++++++++++++++ > > include/linux/pci-epc.h | 1 + > > include/linux/pci-epf.h | 1 + > > 3 files changed, 21 insertions(+) > > > > diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c > > index adec9bee72cf..86b6934c6297 100644 > > --- a/drivers/pci/endpoint/pci-epc-core.c > > +++ b/drivers/pci/endpoint/pci-epc-core.c > > @@ -658,6 +658,25 @@ void pci_epc_init_notify(struct pci_epc *epc) > > } > > EXPORT_SYMBOL_GPL(pci_epc_init_notify); > > > > +/** > > + * pci_epc_custom_notify() - Notify the EPF device about the custom events > > + * in the EPC device > > + * @epc: EPC device that generates the custom notification > > + * @data: Data for the custom notifier > > + * > > + * Invoke to notify the EPF device about the custom events in the EPC device. > > + * This notifier can be used to pass the EPC specific custom events that are > > + * shared with the EPF device. > > + */ > > +void pci_epc_custom_notify(struct pci_epc *epc, void *data) > > +{ > > + if (!epc || IS_ERR(epc)) > > + return; > > + > > + atomic_notifier_call_chain(&epc->notifier, CUSTOM, data); > > +} > > +EXPORT_SYMBOL_GPL(pci_epc_custom_notify); > > + > > /** > > * pci_epc_destroy() - destroy the EPC device > > * @epc: the EPC device that has to be destroyed > > diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h > > index b82c9b100e97..13140fdbcdf6 100644 > > --- a/include/linux/pci-epc.h > > +++ b/include/linux/pci-epc.h > > @@ -203,6 +203,7 @@ int pci_epc_add_epf(struct pci_epc *epc, struct pci_epf *epf, > > enum pci_epc_interface_type type); > > void pci_epc_linkup(struct pci_epc *epc); > > void pci_epc_init_notify(struct pci_epc *epc); > > +void pci_epc_custom_notify(struct pci_epc *epc, void *data); > > void pci_epc_remove_epf(struct pci_epc *epc, struct pci_epf *epf, > > enum pci_epc_interface_type type); > > int pci_epc_write_header(struct pci_epc *epc, u8 func_no, > > diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h > > index 6833e2160ef1..8d740c5cf0e3 100644 > > --- a/include/linux/pci-epf.h > > +++ b/include/linux/pci-epf.h > > @@ -20,6 +20,7 @@ enum pci_epc_interface_type; > > enum pci_notify_event { > > CORE_INIT, > > LINK_UP, > > + CUSTOM, > > }; > > > > enum pci_barno { > >
