Hi, On 4/18/23 10:48, Sarannya S wrote: > From: Deepak Kumar Singh <quic_deesin@xxxxxxxxxxx> > > Some transports like Glink support the state notifications between > clients using flow control signals similar to serial protocol signals. > Local glink client drivers can send and receive flow control status > to glink clients running on remote processors. > > Add APIs to support sending and receiving of flow control status by > rpmsg clients. > > Signed-off-by: Deepak Kumar Singh <quic_deesin@xxxxxxxxxxx> > Signed-off-by: Sarannya S <quic_sarannya@xxxxxxxxxxx> > --- > drivers/rpmsg/rpmsg_core.c | 20 ++++++++++++++++++++ > drivers/rpmsg/rpmsg_internal.h | 2 ++ > 2 files changed, 22 insertions(+) > > diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c > index a2207c0..86b4912 100644 > --- a/drivers/rpmsg/rpmsg_core.c > +++ b/drivers/rpmsg/rpmsg_core.c > @@ -331,6 +331,24 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, > EXPORT_SYMBOL(rpmsg_trysend_offchannel); > > /** > + * rpmsg_set_flow_control() - sets/clears serial flow control signals > + * @ept: the rpmsg endpoint > + * @enable: pause/resume incoming data flow > + * > + * Return: 0 on success and an appropriate error value on failure. > + */ > +int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable) Regression since V4[1] In V4 version the function was: int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable, u32 dst) Following comments on V3 [2] Without dst parameter it is not compatible with the rpmsg_virtio backend [1]https://lkml.org/lkml/2022/12/7/506 [2]https://www.spinics.net/lists/kernel/msg4573082.html Regards Arnaud > +{ > + if (WARN_ON(!ept)) > + return -EINVAL; > + if (!ept->ops->set_flow_control) > + return -ENXIO; > + > + return ept->ops->set_flow_control(ept, enable); > +} > +EXPORT_SYMBOL(rpmsg_set_flow_control); > + > +/** > * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. > * @ept: the rpmsg endpoint > * > @@ -539,6 +557,8 @@ static int rpmsg_dev_probe(struct device *dev) > > rpdev->ept = ept; > rpdev->src = ept->addr; > + > + ept->flow_cb = rpdrv->flowcontrol; > } > > err = rpdrv->probe(rpdev); > diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h > index 39b646d..4fea45a 100644 > --- a/drivers/rpmsg/rpmsg_internal.h > +++ b/drivers/rpmsg/rpmsg_internal.h > @@ -55,6 +55,7 @@ struct rpmsg_device_ops { > * @trysendto: see @rpmsg_trysendto(), optional > * @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional > * @poll: see @rpmsg_poll(), optional > + * @set_flow_control: see @rpmsg_set_flow_control(), optional > * @get_mtu: see @rpmsg_get_mtu(), optional > * > * Indirection table for the operations that a rpmsg backend should implement. > @@ -75,6 +76,7 @@ struct rpmsg_endpoint_ops { > void *data, int len); > __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp, > poll_table *wait); > + int (*set_flow_control)(struct rpmsg_endpoint *ept, bool enable); > ssize_t (*get_mtu)(struct rpmsg_endpoint *ept); > }; >
