LXR linux/drivers/clk/at91/clk-slow.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * drivers/clk/at91/clk-slow.c
   4 *
   5 *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
   6 */
   7
   8#include <linux/clk-provider.h>
   9#include <linux/clkdev.h>
  10#include <linux/clk/at91_pmc.h>
  11#include <linux/of.h>
  12#include <linux/mfd/syscon.h>
  13#include <linux/regmap.h>
  14
  15#include "pmc.h"
  16
  17struct clk_sam9260_slow {
  18        struct clk_hw hw;
  19        struct regmap *regmap;
  20};
  21
  22#define to_clk_sam9260_slow(hw) container_of(hw, struct clk_sam9260_slow, hw)
  23
  24static u8 clk_sam9260_slow_get_parent(struct clk_hw *hw)
  25{
  26        struct clk_sam9260_slow *slowck = to_clk_sam9260_slow(hw);
  27        unsigned int status;
  28
  29        regmap_read(slowck->regmap, AT91_PMC_SR, &status);
  30
  31        return status & AT91_PMC_OSCSEL ? 1 : 0;
  32}
  33
  34static const struct clk_ops sam9260_slow_ops = {
  35        .get_parent = clk_sam9260_slow_get_parent,
  36};
  37
  38struct clk_hw * __init
  39at91_clk_register_sam9260_slow(struct regmap *regmap,
  40                               const char *name,
  41                               const char **parent_names,
  42                               int num_parents)
  43{
  44        struct clk_sam9260_slow *slowck;
  45        struct clk_hw *hw;
  46        struct clk_init_data init;
  47        int ret;
  48
  49        if (!name)
  50                return ERR_PTR(-EINVAL);
  51
  52        if (!parent_names || !num_parents)
  53                return ERR_PTR(-EINVAL);
  54
  55        slowck = kzalloc(sizeof(*slowck), GFP_KERNEL);
  56        if (!slowck)
  57                return ERR_PTR(-ENOMEM);
  58
  59        init.name = name;
  60        init.ops = &sam9260_slow_ops;
  61        init.parent_names = parent_names;
  62        init.num_parents = num_parents;
  63        init.flags = 0;
  64
  65        slowck->hw.init = &init;
  66        slowck->regmap = regmap;
  67
  68        hw = &slowck->hw;
  69        ret = clk_hw_register(NULL, &slowck->hw);
  70        if (ret) {
  71                kfree(slowck);
  72                hw = ERR_PTR(ret);
  73        }
  74
  75        return hw;
  76}
  77