drivers/clk/ti/fixed-factor.c

   1 /*
   2  * TI Fixed Factor Clock
   3  *
   4  * Copyright (C) 2013 Texas Instruments, Inc.
   5  *
   6  * Tero Kristo <t-kristo@ti.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  13  * kind, whether express or implied; without even the implied warranty
  14  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 #include <linux/clk-provider.h>
  19 #include <linux/slab.h>
  20 #include <linux/err.h>
  21 #include <linux/of.h>
  22 #include <linux/of_address.h>
  23 #include <linux/clk/ti.h>
  24
  25 #include "clock.h"
  26
  27 #undef pr_fmt
  28 #define pr_fmt(fmt) "%s: " fmt, __func__
  29
  30 /**
  31  * of_ti_fixed_factor_clk_setup - Setup function for TI fixed factor clock
  32  * @node: device node for this clock
  33  *
  34  * Sets up a simple fixed factor clock based on device tree info.
  35  */
  36 static void __init of_ti_fixed_factor_clk_setup(struct device_node *node)
  37 {
  38         struct clk *clk;
  39         const char *clk_name = node->name;
  40         const char *parent_name;
  41         u32 div, mult;
  42         u32 flags = 0;
  43
  44         if (of_property_read_u32(node, "ti,clock-div", &div)) {
  45                 pr_err("%s must have a clock-div property\n", node->name);
  46                 return;
  47         }
  48
  49         if (of_property_read_u32(node, "ti,clock-mult", &mult)) {
  50                 pr_err("%s must have a clock-mult property\n", node->name);
  51                 return;
  52         }
  53
  54         if (of_property_read_bool(node, "ti,set-rate-parent"))
  55                 flags |= CLK_SET_RATE_PARENT;
  56
  57         parent_name = of_clk_get_parent_name(node, 0);
  58
  59         clk = clk_register_fixed_factor(NULL, clk_name, parent_name, flags,
  60                                         mult, div);
  61
  62         if (!IS_ERR(clk)) {
  63                 of_clk_add_provider(node, of_clk_src_simple_get, clk);
  64                 of_ti_clk_autoidle_setup(node);
  65                 ti_clk_add_alias(NULL, clk, clk_name);
  66         }
  67 }
  68 CLK_OF_DECLARE(ti_fixed_factor_clk, "ti,fixed-factor-clock",
  69                of_ti_fixed_factor_clk_setup);