On Wed, Aug 02, 2023 at 09:21:18AM +0530, Krishna chaitanya chundru wrote:
> Add support to notify the EPF device about the D-state change event
> from the EPC device.
>
> Signed-off-by: Krishna chaitanya chundru <quic_krichai@xxxxxxxxxxx>
> ---
> Documentation/PCI/endpoint/pci-endpoint.rst | 4 ++++
> drivers/pci/endpoint/pci-epc-core.c | 27 +++++++++++++++++++++++++++
> include/linux/pci-epc.h | 1 +
> include/linux/pci-epf.h | 1 +
> 4 files changed, 33 insertions(+)
>
> diff --git a/Documentation/PCI/endpoint/pci-endpoint.rst b/Documentation/PCI/endpoint/pci-endpoint.rst
> index 4f5622a..66f3191 100644
> --- a/Documentation/PCI/endpoint/pci-endpoint.rst
> +++ b/Documentation/PCI/endpoint/pci-endpoint.rst
> @@ -78,6 +78,10 @@ by the PCI controller driver.
> Cleanup the pci_epc_mem structure allocated during pci_epc_mem_init().
>
>
> +* pci_epc_dstate_notity()
s/notity/notify/ (several instances)
> +
> + Notify all the function drivers that the EPC device has changed its D-state.
> +
> EPC APIs for the PCI Endpoint Function Driver
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
> index 6c54fa5..4cf9c82 100644
> --- a/drivers/pci/endpoint/pci-epc-core.c
> +++ b/drivers/pci/endpoint/pci-epc-core.c
> @@ -785,6 +785,33 @@ void pci_epc_bme_notify(struct pci_epc *epc)
> EXPORT_SYMBOL_GPL(pci_epc_bme_notify);
>
> /**
> + * pci_epc_dstate_notity() - Notify the EPF driver that EPC device D-state
> + * has changed
> + * @epc: the EPC device which has change in D-state
> + * @state: the changed D-state
> + *
> + * Invoke to Notify the EPF device that the EPC device has D-state has
> + * changed.
s/device has D-state/device D-state/
> + */
> +void pci_epc_dstate_notity(struct pci_epc *epc, pci_power_t state)
> +{
> + struct pci_epf *epf;
> +
> + if (!epc || IS_ERR(epc))
> + return;
Is this needed? Looks like a programming error if we return here. I
don't like silently ignoring errors like this. I generally prefer
taking the NULL pointer dereference oops so we know the caller is
broken and can fix it.
> + mutex_lock(&epc->list_lock);
> + list_for_each_entry(epf, &epc->pci_epf, list) {
> + mutex_lock(&epf->lock);
> + if (epf->event_ops && epf->event_ops->dstate_notify)
> + epf->event_ops->dstate_notify(epf, state);
> + mutex_unlock(&epf->lock);
> + }
> + mutex_unlock(&epc->list_lock);
> +}
> +EXPORT_SYMBOL_GPL(pci_epc_dstate_notity);
> +
> +/**
> * 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 5cb6940..26a1108 100644
> --- a/include/linux/pci-epc.h
> +++ b/include/linux/pci-epc.h
> @@ -251,4 +251,5 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc,
> phys_addr_t *phys_addr, size_t size);
> void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr,
> void __iomem *virt_addr, size_t size);
> +void pci_epc_dstate_change(struct pci_epc *epc, pci_power_t state);
> #endif /* __LINUX_PCI_EPC_H */
> diff --git a/include/linux/pci-epf.h b/include/linux/pci-epf.h
> index 3f44b6a..529075b 100644
> --- a/include/linux/pci-epf.h
> +++ b/include/linux/pci-epf.h
> @@ -79,6 +79,7 @@ struct pci_epc_event_ops {
> int (*link_up)(struct pci_epf *epf);
> int (*link_down)(struct pci_epf *epf);
> int (*bme)(struct pci_epf *epf);
> + int (*dstate_notify)(struct pci_epf *epf, pci_power_t state);
> };
>
> /**
> --
> 2.7.4
>
