dt-bindings: phy: Add Freescale i.MX8qm Mixel LVDS PHY binding

Add bindings for Mixel LVDS PHY found on Freescale i.MX8qm SoC.

Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Signed-off-by: Liu Ying <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

Documentation/devicetree/bindings/phy/fsl,imx8qm-lvds-phy.yaml

···
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/fsl,imx8qm-lvds-phy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Mixel LVDS PHY for Freescale i.MX8qm SoC
+
+maintainers:
+  - Liu Ying <[e-mail]>
+
+description: |
+  The Mixel LVDS PHY IP block is found on Freescale i.MX8qm SoC.
+  It converts two groups of four 7/10 bits of CMOS data into two
+  groups of four data lanes of LVDS data streams. A phase-locked
+  transmit clock is transmitted in parallel with each group of
+  data streams over a fifth LVDS link. Every cycle of the transmit
+  clock, 56/80 bits of input data are sampled and transmitted
+  through the two groups of LVDS data streams. Together with the
+  transmit clocks, the two groups of LVDS data streams form two
+  LVDS channels.
+
+  The Mixel LVDS PHY found on Freescale i.MX8qm SoC is controlled
+  by Control and Status Registers(CSR) module in the SoC. The CSR
+  module, as a system controller, contains the PHY's registers.
+
+properties:
+  compatible:
+    enum:
+      - fsl,imx8qm-lvds-phy
+      - mixel,28fdsoi-lvds-1250-8ch-tx-pll
+
+  "#phy-cells":
+    const: 1
+    description: |
+      Cell allows setting the LVDS channel index of the PHY.
+      Index 0 is for LVDS channel0 and index 1 is for LVDS channel1.
+
+  clocks:
+    maxItems: 1
+
+  power-domains:
+    maxItems: 1
+
+required:
+  - compatible
+  - "#phy-cells"
+  - clocks
+  - power-domains
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/firmware/imx/rsrc.h>
+    phy {
+        compatible = "fsl,imx8qm-lvds-phy";
+        #phy-cells = <1>;
+        clocks = <&clk IMX_SC_R_LVDS_0 IMX_SC_PM_CLK_PHY>;
+        power-domains = <&pd IMX_SC_R_LVDS_0>;
+    };