bus: fsl-mc: list more commands as accepted through the ioctl

Add some new MC firmware commands that can be received through the
userspace ioctl interface - *get_max_frame_length and *_get_counter.

Acked-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20210208170949.3070898-4-ciorneiioana@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

bus: fsl-mc: Fix test for end of loop

The "desc" pointer can't possibly be NULL here. If we can't find the
correct "desc" then tt points to the last element of the
fsl_mc_accepted_cmds[] array. Fix this by testing if
"i == FSL_MC_NUM_ACCEPTED_CMDS" instead.

Fixes: 2cf1e703f066 ("bus: fsl-mc: add fsl-mc userspace support")
Acked-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20210208170949.3070898-2-ciorneiioana@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

bus: fsl-mc: add fsl-mc userspace support

Adding userspace support for the MC (Management Complex) means exporting
an ioctl capable device file representing the root resource container.

This new functionality in the fsl-mc bus driver intends to provide
userspace applications an interface to interact with the MC firmware.

Commands that are composed in userspace are sent to the MC firmware
through the FSL_MC_SEND_MC_COMMAND ioctl. By default the implicit MC
I/O portal is used for this operation, but if the implicit one is busy,
a dynamic portal is allocated and then freed upon execution.

The command received through the ioctl interface is checked against a
known whitelist of accepted MC commands. Commands that attempt a change
in hardware configuration will need CAP_NET_ADMIN, while commands used
in debugging do not need it.

Acked-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Link: https://lore.kernel.org/r/20210114170752.2927915-4-ciorneiioana@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>