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clk: stm32f4: Update DT bindings documentation
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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@st.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
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Gabriel Fernandez authored and Stephen Boyd committed Dec 22, 2016
1 parent 2aab7a2 commit f8b5036
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17 changes: 17 additions & 0 deletions Documentation/devicetree/bindings/clock/st,stm32-rcc.txt
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,9 @@ 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)
- external I2S clock (I2S_CKIN)

Example:

Expand All @@ -25,6 +28,7 @@ Example:
#clock-cells = <2>
compatible = "st,stm32f42xx-rcc", "st,stm32-rcc";
reg = <0x40023800 0x400>;
clocks = <&clk_hse>, <&clk_i2s_ckin>;
};

Specifying gated clocks
Expand Down Expand Up @@ -66,6 +70,19 @@ 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)
6 PLL_VCO_I2S (vco frequency of I2S pll)
7 PLL_VCO_SAI (vco frequency of SAI pll)
8 CLK_LCD (LCD-TFT)
9 CLK_I2S (I2S clocks)
10 CLK_SAI1 (audio clocks)
11 CLK_SAI2
12 CLK_I2SQ_PDIV (post divisor of pll i2s q divisor)
13 CLK_SAIQ_PDIV (post divisor of pll sai q divisor)

Example:

Expand Down
39 changes: 39 additions & 0 deletions include/dt-bindings/clock/stm32fx-clock.h
Original file line number Diff line number Diff line change
@@ -0,0 +1,39 @@
/*
* stm32fx-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_STMFX_H
#define _DT_BINDINGS_CLK_STMFX_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 PLL_VCO_I2S 6
#define PLL_VCO_SAI 7
#define CLK_LCD 8
#define CLK_I2S 9
#define CLK_SAI1 10
#define CLK_SAI2 11
#define CLK_I2SQ_PDIV 12
#define CLK_SAIQ_PDIV 13

#define END_PRIMARY_CLK 14

#endif

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