[PATCH v2 2/4] doc: dt: add documentation for lpc1850-cgu clk driver

Joachim Eastwood
2015-04-27T21:38:11Z

Add DT binding documentation for lpc1850-cgu driver.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
---
.../devicetree/bindings/clock/lpc1850-cgu.txt | 138 +++++++++++++++++++++
1 file changed, 138 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/lpc1850-cgu.txt

diff --git a/Documentation/devicetree/bindings/clock/lpc1850-cgu.txt b/Documentation/devicetree/bindings/clock/lpc1850-cgu.txt
new file mode 100644
index 000000000000..0b278ca6aee7
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/lpc1850-cgu.txt
@@ -0,0 +1,138 @@
+* NXP LPC1850 Clock Generation Unit (CGU)
+
+The CGU generates multiple independent clocks for the core and the
+peripheral blocks of the LPC18xx. Each independent clock is called
+a base clock and itself is one of the inputs to the two Clock
+Control Units (CCUs) which control the branch clocks to the
+individual peripherals.
+
+The CGU selects the inputs to the clock generators from multiple
+clock sources, controls the clock generation, and routes the outputs
+of the clock generators through the clock source bus to the output
+stages. Each output stage provides an independent clock source and
+corresponds to one of the base clocks for the LPC18xx.
+
+ - Above text taken from NXP LPC1850 User Manual.
+
+
+This binding uses the common clock binding:
+ Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible:
+ Should be "nxp,lpc1850-cgu"
+- reg:
+ Shall define the base and range of the address space
+ containing clock control registers
+- #clock-cells:
+ Shall have value <1>. The permitted clock-specifier values
+ are the base clock numbers defined below.
+- clocks:
+ Shall contain a list of phandles for the external input
+ sources to the CGU. The list shall be in the following
+ order: xtal, 32khz, enet_rx_clk, enet_tx_clk, gp_clkin.
+- clock-indices:
+ Shall be an ordered list of numbers defining the base clock
+ number provided by the CGU.
+- clock-output-names:
+ Shall be an ordered list of strings defining the names of
+ the clocks provided by the CGU.
+
+Which base clocks that are available on the CGU depends on the
+specific LPC part. Base cloks are numbered from 0 to 27.
+
+Number: Name: Description:
+ 0 BASE_SAFE_CLK Base safe clock (always on) for WWDT
+ 1 BASE_USB0_CLK Base clock for USB0
+ 2 BASE_PERIPH_CLK Base clock for Cortex-M0SUB subsystem,
+ SPI, and SGPIO
+ 3 BASE_USB1_CLK Base clock for USB1
+ 4 BASE_CPU_CLK System base clock for ARM Cortex-M core
+ and APB peripheral blocks #0 and #2
+ 5 BASE_SPIFI_CLK Base clock for SPIFI
+ 6 BASE_SPI_CLK Base clock for SPI
+ 7 BASE_PHY_RX_CLK Base clock for Ethernet PHY Receive clock
+ 8 BASE_PHY_TX_CLK Base clock for Ethernet PHY Transmit clock
+ 9 BASE_APB1_CLK Base clock for APB peripheral block # 1
+10 BASE_APB3_CLK Base clock for APB peripheral block # 3
+11 BASE_LCD_CLK Base clock for LCD
+12 BASE_ADCHS_CLK Base clock for ADCHS
+13 BASE_SDIO_CLK Base clock for SD/MMC
+14 BASE_SSP0_CLK Base clock for SSP0
+15 BASE_SSP1_CLK Base clock for SSP1
+16 BASE_UART0_CLK Base clock for UART0
+17 BASE_UART1_CLK Base clock for UART1
+18 BASE_UART2_CLK Base clock for UART2
+19 BASE_UART3_CLK Base clock for UART3
+20 BASE_OUT_CLK Base clock for CLKOUT pin
+24-21 - Reserved
+25 BASE_AUDIO_CLK Base clock for audio system (I2S)
+26 BASE_CGU_OUT0_CLK Base clock for CGU_OUT0 clock output
+27 BASE_CGU_OUT1_CLK Base clock for CGU_OUT1 clock output
+
+BASE_PERIPH_CLK and BASE_SPI_CLK is only available on LPC43xx.
+BASE_ADCHS_CLK is only available on LPC4370.
+
+
+Example board file:
+
+/ {
+ clocks {
+ xtal: xtal {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <12000000>;
+ };
+
+ xtal32: xtal32 {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <32768>;
+ };
+
+ enet_rx_clk: enet_rx_clk {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <0>;
+ clock-output-names = "enet_rx_clk";
+ };
+
+ enet_tx_clk: enet_tx_clk {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <0>;
+ clock-output-names = "enet_tx_clk";
+ };
+
+ gp_clkin: gp_clkin {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <0>;
+ clock-output-names = "gp_clkin";
+ };
+ };
+
+ soc {
+ cgu: cgu@40050000 {
+ compatible = "nxp,lpc1850-cgu";
+ reg = <0x40050000 0x1000>;
+ #clock-cells = <1>;
+ clocks = <&xtal>, <&creg_clk 1>, <&enet_rx_clk>, <&enet_tx_clk>, <&gp_clkin>;
+ clock-indices = <0>, <1>, <2>, <3>, <4>, <5>, <6>, <7>,
+ <8>, <9>, <10>, <11>, <12>, <13>, <14>, <15>,
+ <16>, <17>, <18>, <19>, <20>, <25>, <26>, <27>;
+ clock-output-names = "base_safe_clk", "base_usb0_clk",
+ "base_periph_clk", "base_usb1_clk",
+ "base_cpu_clk", "base_spifi_clk",
+ "base_spi_clk", "base_phy_rx_clk",
+ "base_phy_tx_clk", "base_apb1_clk",
+ "base_apb3_clk", "base_lcd_clk",
+ "base_adchs_clk", "base_sdio_clk",
+ "base_ssp0_clk", "base_ssp1_clk",
+ "base_uart0_clk", "base_uart1_clk",
+ "base_uart2_clk", "base_uart3_clk",
+ "base_out_clk", "base_audio_clk",
+ "base_cgu_out0_clk","base_cgu_out1_clk";
+ };
+ };
+};
--
1.8.0