arch/arm/plat-samsung/include/plat/clock-clksrc.h

   1 /* linux/arch/arm/plat-samsung/include/plat/clock-clksrc.h
   2  *
   3  * Parts taken from arch/arm/plat-s3c64xx/clock.c
   4  *      Copyright 2008 Openmoko, Inc.
   5  *      Copyright 2008 Simtec Electronics
   6  *              Ben Dooks <ben@simtec.co.uk>
   7  *              http://armlinux.simtec.co.uk/
   8  *
   9  * Copyright 2009 Ben Dooks <ben-linux@fluff.org>
  10  * Copyright 2009 Harald Welte
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15 */
  16
  17 /**
  18  * struct clksrc_sources - list of sources for a given clock
  19  * @sources: array of pointers to clocks
  20  * @nr_sources: The size of @sources
  21  */
  22 struct clksrc_sources {
  23         unsigned int    nr_sources;
  24         struct clk      **sources;
  25 };
  26
  27 /**
  28  * struct clksrc_reg - register definition for clock control bits
  29  * @reg: pointer to the register in virtual memory.
  30  * @shift: the shift in bits to where the bitfield is.
  31  * @size: the size in bits of the bitfield.
  32  *
  33  * This specifies the size and position of the bits we are interested
  34  * in within the register specified by @reg.
  35  */
  36 struct clksrc_reg {
  37         void __iomem            *reg;
  38         unsigned short          shift;
  39         unsigned short          size;
  40 };
  41
  42 /**
  43  * struct clksrc_clk - class of clock for newer style samsung devices.
  44  * @clk: the standard clock representation
  45  * @sources: the sources for this clock
  46  * @reg_src: the register definition for selecting the clock's source
  47  * @reg_div: the register definition for the clock's output divisor
  48  *
  49  * This clock implements the features required by the newer SoCs where
  50  * the standard clock block provides an input mux and a post-mux divisor
  51  * to provide the periperhal's clock.
  52  *
  53  * The array of @sources provides the mapping of mux position to the
  54  * clock, and @reg_src shows the code where to modify to change the mux
  55  * position. The @reg_div defines how to change the divider settings on
  56  * the output.
  57  */
  58 struct clksrc_clk {
  59         struct clk              clk;
  60         struct clksrc_sources   *sources;
  61
  62         struct clksrc_reg       reg_src;
  63         struct clksrc_reg       reg_div;
  64 };
  65
  66 /**
  67  * s3c_set_clksrc() - setup the clock from the register settings
  68  * @clk: The clock to setup.
  69  * @announce: true to announce the setting to printk().
  70  *
  71  * Setup the clock from the current register settings, for when the
  72  * kernel boots or if it is resuming from a possibly unknown state.
  73  */
  74 extern void s3c_set_clksrc(struct clksrc_clk *clk, bool announce);
  75
  76 /**
  77  * s3c_register_clksrc() register clocks from an array of clksrc clocks
  78  * @srcs: The array of clocks to register
  79  * @size: The size of the @srcs array.
  80  *
  81  * Initialise and register the array of clocks described by @srcs.
  82  */
  83 extern void s3c_register_clksrc(struct clksrc_clk *srcs, int size);