[PATCH v2 1/9] clk: stm32f4: Update DT bindings documentation

From: gabriel.fernandez
Date: Thu Nov 24 2016 - 09:49:09 EST


From: Gabriel Fernandez <gabriel.fernandez@xxxxxx>

Creation of dt include file for specific stm32f4 clocks.
These specific clocks are not derived from system clock (SYSCLOCK)
We should use index 1 to use these clocks in DT.
e.g. <&rcc 1 CLK_LSI>

Signed-off-by: Gabriel Fernandez <gabriel.fernandez@xxxxxx>
---
.../devicetree/bindings/clock/st,stm32-rcc.txt | 8 ++++++
drivers/clk/clk-stm32f4.c | 9 +++++--
include/dt-bindings/clock/stm32f4-clock.h | 31 ++++++++++++++++++++++
3 files changed, 46 insertions(+), 2 deletions(-)
create mode 100644 include/dt-bindings/clock/stm32f4-clock.h

diff --git a/Documentation/devicetree/bindings/clock/st,stm32-rcc.txt b/Documentation/devicetree/bindings/clock/st,stm32-rcc.txt
index 0532d81..18e05c2 100644
--- a/Documentation/devicetree/bindings/clock/st,stm32-rcc.txt
+++ b/Documentation/devicetree/bindings/clock/st,stm32-rcc.txt
@@ -17,6 +17,8 @@ Required properties:
property, containing a phandle to the clock device node, an index selecting
between gated clocks and other clocks and an index specifying the clock to
use.
+- clocks: External oscillator clock phandle
+ - high speed external clock signal (HSE)

Example:

@@ -25,6 +27,7 @@ Example:
#clock-cells = <2>
compatible = "st,stm32f42xx-rcc", "st,stm32-rcc";
reg = <0x40023800 0x400>;
+ clocks = <&clk_hse>;
};

Specifying gated clocks
@@ -66,6 +69,11 @@ The secondary index is bound with the following magic numbers:

0 SYSTICK
1 FCLK
+ 2 CLK_LSI (low-power clock source)
+ 3 CLK_LSE (generated from a 32.768 kHz low-speed external
+ crystal or ceramic resonator)
+ 4 CLK_HSE_RTC (HSE division factor for RTC clock)
+ 5 CLK_RTC (real-time clock)

Example:

diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c
index 5eb05db..39965ab 100644
--- a/drivers/clk/clk-stm32f4.c
+++ b/drivers/clk/clk-stm32f4.c
@@ -28,6 +28,13 @@
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>

+/*
+ * Include list of clocks wich are not derived from system clock (SYSCLOCK)
+ * The index of these clocks is the secondary index of DT bindings
+ *
+ */
+#include <dt-bindings/clock/stm32f4-clock.h>
+
#define STM32F4_RCC_PLLCFGR 0x04
#define STM32F4_RCC_CFGR 0x08
#define STM32F4_RCC_AHB1ENR 0x30
@@ -208,8 +215,6 @@ struct stm32f4_gate_data {
{ STM32F4_RCC_APB2ENR, 26, "ltdc", "apb2_div" },
};

-enum { SYSTICK, FCLK, CLK_LSI, CLK_LSE, CLK_HSE_RTC, CLK_RTC, END_PRIMARY_CLK };
-
/*
* This bitmask tells us which bit offsets (0..192) on STM32F4[23]xxx
* have gate bits associated with them. Its combined hweight is 71.
diff --git a/include/dt-bindings/clock/stm32f4-clock.h b/include/dt-bindings/clock/stm32f4-clock.h
new file mode 100644
index 0000000..3132b6a
--- /dev/null
+++ b/include/dt-bindings/clock/stm32f4-clock.h
@@ -0,0 +1,31 @@
+/*
+ * stm32f4-clock.h
+ *
+ * Copyright (C) 2016 STMicroelectronics
+ * Author: Gabriel Fernandez for STMicroelectronics.
+ * License terms: GNU General Public License (GPL), version 2
+ */
+
+/*
+ * List of clocks wich are not derived from system clock (SYSCLOCK)
+ *
+ * The index of these clocks is the secondary index of DT bindings
+ * (see Documentatoin/devicetree/bindings/clock/st,stm32-rcc.txt)
+ *
+ * e.g:
+ <assigned-clocks = <&rcc 1 CLK_LSE>;
+*/
+
+#ifndef _DT_BINDINGS_CLK_STMF4_H
+#define _DT_BINDINGS_CLK_STMF4_H
+
+#define SYSTICK 0
+#define FCLK 1
+#define CLK_LSI 2
+#define CLK_LSE 3
+#define CLK_HSE_RTC 4
+#define CLK_RTC 5
+
+#define END_PRIMARY_CLK 6
+
+#endif
--
1.9.1