On 12/3/18 11:45 AM, Greg KH wrote: > On Mon, Dec 03, 2018 at 11:30:29AM -0600, Dinh Nguyen wrote: >> From: Ramiro Oliveira <Ramiro.Oliveira@xxxxxxxxxxxx> >> >> commit bb475230b8e59a547ab66ac3b02572df21a580e9 upstream. >> >> The *_get_optional_* functions weren't really optional so this patch >> makes them really optional. >> >> These *_get_optional_* functions will now return NULL instead of an error >> if no matching reset phandle is found in the DT, and all the >> reset_control_* functions now accept NULL rstc pointers. >> >> Signed-off-by: Ramiro Oliveira <Ramiro.Oliveira@xxxxxxxxxxxx> >> Signed-off-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> >> --- >> Please apply to v4.9.y stable tree. >> --- >> drivers/reset/core.c | 48 +++++++++++++++++++++++++++++++++---------- >> include/linux/reset.h | 45 +++++++++++++++++++++++----------------- >> 2 files changed, 63 insertions(+), 30 deletions(-) > > What problem is this solving? Why is this suddenly needed now? > The v4.9-stable branch has this patch for stmmac ethernet driver: "6f37f7b62baa net: stmmac: socfpga: add additional ocp reset line for Stratix10" This patch calls devm_reset_control_get_optional(). This call ultimately fails without optional reset patch, causing the ethernet driver to fail to load. Dinh
