clk: imx: clk-gpr-mux: Simplify .determine_rate()

imx_clk_gpr_mux_determine_rate() is the same as __clk_mux_determine_rate(),
so use the latter to save some LoC.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/ac8bd50c41b84f244bb0ec94e8aed25c513c9037.1688760152.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>

clk: imx: clk-gpr-mux: Provide clock name in error message

In error case the error message doesn't provide much context:

imx:clk-gpr-mux: failed to get parent (-EINVAL)

So additionally provide the clock name in the message, in
order to simplify the further analyze.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Link: https://lore.kernel.org/r/20230308184603.10049-1-stefan.wahren@i2se.com

clk: imx: set imx_clk_gpr_mux_ops storage-class-specifier to static

smatch reports
drivers/clk/imx/clk-gpr-mux.c:73:22: warning: symbol 'imx_clk_gpr_mux_ops' was not declared. Should it be static?

imx_clk_gpr_mux_ops is only used in clk-gpr-mux.c, so it should be static.

Signed-off-by: Tom Rix <trix@redhat.com>
Link: https://lore.kernel.org/r/20230205030138.1723614-1-trix@redhat.com
Fixes: ee394f636ad3 ("clk: imx: add clk-gpr-mux driver")
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: imx: add clk-gpr-mux driver

Almost(?) every i.MX variant has clk mux for ethernet (rgmii/rmii) reference
clock located in the GPR1 register. So far this clk is configured in
different ways:
- mach-imx6q is doing mux configuration based on ptp vs enet_ref clk
comparison.
- mach-imx7d is setting mux to PAD for all boards
- mach-imx6ul is setting mux to internal clock for all boards.

Since we have imx7d and imx6ul board variants which do not work with
configurations forced by kernel mach code, we need to implement this clk
mux properly as part of the clk framework. Which is done by this patch.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Abel Vesa <abel.vesa@linaro.org>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Link: https://lore.kernel.org/r/20230131084642.709385-2-o.rempel@pengutronix.de