DEVICETREE: Add Ingenic CGU binding documentation

Document the devicetree binding for Ingenic SoC CGUs, and add headers
defining the clock specifiers for clocks provided by the JZ4740 & JZ4780
CGU blocks.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: devicetree@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10152/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

include/dt-bindings/clock/jz4740-cgu.h

@@ -0,0 +1,37 @@
+/*
+ * This header provides clock numbers for the ingenic,jz4740-cgu DT binding.
+ *
+ * They are roughly ordered as:
+ *   - external clocks
+ *   - PLLs
+ *   - muxes/dividers in the order they appear in the jz4740 programmers manual
+ *   - gates in order of their bit in the CLKGR* registers
+ */
+
+#ifndef __DT_BINDINGS_CLOCK_JZ4740_CGU_H__
+#define __DT_BINDINGS_CLOCK_JZ4740_CGU_H__
+
+#define JZ4740_CLK_EXT		0
+#define JZ4740_CLK_RTC		1
+#define JZ4740_CLK_PLL		2
+#define JZ4740_CLK_PLL_HALF	3
+#define JZ4740_CLK_CCLK		4
+#define JZ4740_CLK_HCLK		5
+#define JZ4740_CLK_PCLK		6
+#define JZ4740_CLK_MCLK		7
+#define JZ4740_CLK_LCD		8
+#define JZ4740_CLK_LCD_PCLK	9
+#define JZ4740_CLK_I2S		10
+#define JZ4740_CLK_SPI		11
+#define JZ4740_CLK_MMC		12
+#define JZ4740_CLK_UHC		13
+#define JZ4740_CLK_UDC		14
+#define JZ4740_CLK_UART0	15
+#define JZ4740_CLK_UART1	16
+#define JZ4740_CLK_DMA		17
+#define JZ4740_CLK_IPU		18
+#define JZ4740_CLK_ADC		19
+#define JZ4740_CLK_I2C		20
+#define JZ4740_CLK_AIC		21
+
+#endif /* __DT_BINDINGS_CLOCK_JZ4740_CGU_H__ */