drivers/clk/versatile/clk-integrator.c

   1 /*
   2  * Clock driver for the ARM Integrator/AP and Integrator/CP boards
   3  * Copyright (C) 2012 Linus Walleij
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  */
   9 #include <linux/clk-provider.h>
  10 #include <linux/clk.h>
  11 #include <linux/clkdev.h>
  12 #include <linux/err.h>
  13 #include <linux/of.h>
  14 #include <linux/of_address.h>
  15
  16 #include "clk-icst.h"
  17
  18 #define INTEGRATOR_HDR_LOCK_OFFSET      0x14
  19
  20 /* Base offset for the core module */
  21 static void __iomem *cm_base;
  22
  23 static const struct icst_params cp_auxosc_params = {
  24         .vco_max        = ICST525_VCO_MAX_5V,
  25         .vco_min        = ICST525_VCO_MIN,
  26         .vd_min         = 8,
  27         .vd_max         = 263,
  28         .rd_min         = 3,
  29         .rd_max         = 65,
  30         .s2div          = icst525_s2div,
  31         .idx2s          = icst525_idx2s,
  32 };
  33
  34 static const struct clk_icst_desc __initdata cm_auxosc_desc = {
  35         .params = &cp_auxosc_params,
  36         .vco_offset = 0x1c,
  37         .lock_offset = INTEGRATOR_HDR_LOCK_OFFSET,
  38 };
  39
  40 static void __init of_integrator_cm_osc_setup(struct device_node *np)
  41 {
  42         struct clk *clk = ERR_PTR(-EINVAL);
  43         const char *clk_name = np->name;
  44         const struct clk_icst_desc *desc = &cm_auxosc_desc;
  45         const char *parent_name;
  46
  47         if (!cm_base) {
  48                 /* Remap the core module base if not done yet */
  49                 struct device_node *parent;
  50
  51                 parent = of_get_parent(np);
  52                 if (!np) {
  53                         pr_err("no parent on core module clock\n");
  54                         return;
  55                 }
  56                 cm_base = of_iomap(parent, 0);
  57                 if (!cm_base) {
  58                         pr_err("could not remap core module base\n");
  59                         return;
  60                 }
  61         }
  62
  63         parent_name = of_clk_get_parent_name(np, 0);
  64         clk = icst_clk_register(NULL, desc, clk_name, parent_name, cm_base);
  65         if (!IS_ERR(clk))
  66                 of_clk_add_provider(np, of_clk_src_simple_get, clk);
  67 }
  68 CLK_OF_DECLARE(integrator_cm_auxosc_clk,
  69         "arm,integrator-cm-auxosc", of_integrator_cm_osc_setup);