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| author | Arnaud Pouliquen <arnaud.pouliquen@foss.st.com> | 2021-10-15 11:47:00 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-10-21 12:35:35 +0200 |
| commit | e279317e9aeb11d8670e0a5acb10d50566eea9c9 (patch) | |
| tree | db22091c5a95e1cc5dd73752bb9a7786ca848e47 /drivers/rpmsg | |
| parent | 74365bc138ab03bdac205047aac02f8db0a479fa (diff) | |
| download | linux-e279317e9aeb11d8670e0a5acb10d50566eea9c9.tar.bz2 | |
rpmsg: core: add API to get MTU
Return the rpmsg buffer MTU for sending message, so rpmsg users
can split a long message in several sub rpmsg buffers.
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Link: https://lore.kernel.org/r/20211015094701.5732-2-arnaud.pouliquen@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/rpmsg')
| -rw-r--r-- | drivers/rpmsg/rpmsg_core.c | 21 | ||||
| -rw-r--r-- | drivers/rpmsg/rpmsg_internal.h | 2 | ||||
| -rw-r--r-- | drivers/rpmsg/virtio_rpmsg_bus.c | 10 |
3 files changed, 33 insertions, 0 deletions
diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c index 9151836190ce..d3eb60059ef1 100644 --- a/drivers/rpmsg/rpmsg_core.c +++ b/drivers/rpmsg/rpmsg_core.c @@ -327,6 +327,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, } EXPORT_SYMBOL(rpmsg_trysend_offchannel); +/** + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. + * @ept: the rpmsg endpoint + * + * This function returns maximum buffer size available for a single outgoing message. + * + * Return: the maximum transmission size on success and an appropriate error + * value on failure. + */ + +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) +{ + if (WARN_ON(!ept)) + return -EINVAL; + if (!ept->ops->get_mtu) + return -ENOTSUPP; + + return ept->ops->get_mtu(ept); +} +EXPORT_SYMBOL(rpmsg_get_mtu); + /* * match a rpmsg channel with a channel info struct. * this is used to make sure we're not creating rpmsg devices for channels diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h index a76c344253bf..b1245d3ed7c6 100644 --- a/drivers/rpmsg/rpmsg_internal.h +++ b/drivers/rpmsg/rpmsg_internal.h @@ -53,6 +53,7 @@ struct rpmsg_device_ops { * @trysendto: see @rpmsg_trysendto(), optional * @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional * @poll: see @rpmsg_poll(), optional + * @get_mtu: see @rpmsg_get_mtu(), optional * * Indirection table for the operations that a rpmsg backend should implement. * In addition to @destroy_ept, the backend must at least implement @send and @@ -72,6 +73,7 @@ struct rpmsg_endpoint_ops { void *data, int len); __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp, poll_table *wait); + ssize_t (*get_mtu)(struct rpmsg_endpoint *ept); }; struct device *rpmsg_find_device(struct device *parent, diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c index 8e49a3bacfc7..05fd06fc67e9 100644 --- a/drivers/rpmsg/virtio_rpmsg_bus.c +++ b/drivers/rpmsg/virtio_rpmsg_bus.c @@ -149,6 +149,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, int len, u32 dst); static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, void *data, int len); +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept); static struct rpmsg_device *__rpmsg_create_channel(struct virtproc_info *vrp, struct rpmsg_channel_info *chinfo); @@ -160,6 +161,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { .trysend = virtio_rpmsg_trysend, .trysendto = virtio_rpmsg_trysendto, .trysend_offchannel = virtio_rpmsg_trysend_offchannel, + .get_mtu = virtio_rpmsg_get_mtu, }; /** @@ -696,6 +698,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); } +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept) +{ + struct rpmsg_device *rpdev = ept->rpdev; + struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); + + return vch->vrp->buf_size - sizeof(struct rpmsg_hdr); +} + static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev, struct rpmsg_hdr *msg, unsigned int len) { |