LXR linux/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 */
  22struct 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 */
  36struct 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 */
  58struct 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 */
  74extern 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 */
  83extern void s3c_register_clksrc(struct clksrc_clk *srcs, int size);
  84