As introduction on the get_mtu api can impacts some rpmsg drivers, i propose to discuss it separately. The "rpmsg: core: add API to get message length" patch is extracted from https://lkml.org/lkml/2019/9/4/556 In addition 2 patches implement the API for impacted rpmsg drivers. The rpmsg tty client driver will be resent in a second step. In this patchset the get_mpu is considered mandatory. The main reason is that the rpmsg clients do not have access to the mtu information that is platform dependent. Notice that the GLINK and and SMD drivers have to be validated on target, I don't have device to validate by myself... Only a compilation check has been executed. Arnaud Pouliquen (3): rpmsg: core: add API to get message length rpmsg: glink: implement get_mtu ops rpmsg: smd: implement get_mtu ops drivers/rpmsg/qcom_glink_native.c | 24 ++++++++++++++++++++++++ drivers/rpmsg/qcom_smd.c | 8 ++++++++ drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ drivers/rpmsg/rpmsg_internal.h | 2 ++ drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++ include/linux/rpmsg.h | 10 ++++++++++ 6 files changed, 75 insertions(+) -- 2.7.4