clk: imx: Reference preceded by free

When register failed, clk will be freed, it will generate dangling pointer
problem in later reference. it should return directly.

Signed-off-by: Jian Dong <dongjian@yulong.com>
Signed-off-by: Abel Vesa <abel.vesa@nxp.com>

clk: imx: lpcg: add suspend/resume support

LPCG clock state may be lost when it's power domain is completely
off during system suspend/resume and we need save and restore the
state properly.

Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: lpcg: allow lpcg clk to take device pointer

Used to support runtime pm.

Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: imx8qxp-lpcg: add parsing clocks from device tree

One LPCG controller supports up to 8 clock outputs while each of them
is fixed to 4 bits. It supports only gating function with fixed bits.
So we can use the clk-indices to fetch the corresponding clock idx from
device tree. With this way, we can write a generic LPCG clock drivers.

This patch add that support to parse clocks from device tree.

Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Michael Turquette <mturquette@baylibre.com>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: Explicitly include bits.h

It is better to explicitly include the required header file rather
then get it through some recursive include.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

clk: imx: add lpcg clock support

The Low-Power Clock Gate (LPCG) modules contain a local programming
model to control the clock gates for the peripherals. An LPCG module
is used to locally gate the clocks for the associated peripheral.
And they're bedind the SCU clock.

Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>