drivers/clk/mediatek/clk-cpumux.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2015 Linaro Ltd.
   4  * Author: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
   5  */
   6
   7 #include <linux/clk-provider.h>
   8 #include <linux/mfd/syscon.h>
   9 #include <linux/module.h>
  10 #include <linux/slab.h>
  11
  12 #include "clk-mtk.h"
  13 #include "clk-cpumux.h"
  14
  15 static inline struct mtk_clk_cpumux *to_mtk_clk_cpumux(struct clk_hw *_hw)
  16 {
  17         return container_of(_hw, struct mtk_clk_cpumux, hw);
  18 }
  19
  20 static u8 clk_cpumux_get_parent(struct clk_hw *hw)
  21 {
  22         struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
  23         unsigned int val;
  24
  25         regmap_read(mux->regmap, mux->reg, &val);
  26
  27         val >>= mux->shift;
  28         val &= mux->mask;
  29
  30         return val;
  31 }
  32
  33 static int clk_cpumux_set_parent(struct clk_hw *hw, u8 index)
  34 {
  35         struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
  36         u32 mask, val;
  37
  38         val = index << mux->shift;
  39         mask = mux->mask << mux->shift;
  40
  41         return regmap_update_bits(mux->regmap, mux->reg, mask, val);
  42 }
  43
  44 static const struct clk_ops clk_cpumux_ops = {
  45         .get_parent = clk_cpumux_get_parent,
  46         .set_parent = clk_cpumux_set_parent,
  47 };
  48
  49 static struct clk *
  50 mtk_clk_register_cpumux(const struct mtk_composite *mux,
  51                         struct regmap *regmap)
  52 {
  53         struct mtk_clk_cpumux *cpumux;
  54         struct clk *clk;
  55         struct clk_init_data init;
  56
  57         cpumux = kzalloc(sizeof(*cpumux), GFP_KERNEL);
  58         if (!cpumux)
  59                 return ERR_PTR(-ENOMEM);
  60
  61         init.name = mux->name;
  62         init.ops = &clk_cpumux_ops;
  63         init.parent_names = mux->parent_names;
  64         init.num_parents = mux->num_parents;
  65         init.flags = mux->flags;
  66
  67         cpumux->reg = mux->mux_reg;
  68         cpumux->shift = mux->mux_shift;
  69         cpumux->mask = BIT(mux->mux_width) - 1;
  70         cpumux->regmap = regmap;
  71         cpumux->hw.init = &init;
  72
  73         clk = clk_register(NULL, &cpumux->hw);
  74         if (IS_ERR(clk))
  75                 kfree(cpumux);
  76
  77         return clk;
  78 }
  79
  80 int mtk_clk_register_cpumuxes(struct device_node *node,
  81                               const struct mtk_composite *clks, int num,
  82                               struct clk_onecell_data *clk_data)
  83 {
  84         int i;
  85         struct clk *clk;
  86         struct regmap *regmap;
  87
  88         regmap = device_node_to_regmap(node);
  89         if (IS_ERR(regmap)) {
  90                 pr_err("Cannot find regmap for %pOF: %ld\n", node,
  91                        PTR_ERR(regmap));
  92                 return PTR_ERR(regmap);
  93         }
  94
  95         for (i = 0; i < num; i++) {
  96                 const struct mtk_composite *mux = &clks[i];
  97
  98                 clk = mtk_clk_register_cpumux(mux, regmap);
  99                 if (IS_ERR(clk)) {
 100                         pr_err("Failed to register clk %s: %ld\n",
 101                                mux->name, PTR_ERR(clk));
 102                         continue;
 103                 }
 104
 105                 clk_data->clks[mux->id] = clk;
 106         }
 107
 108         return 0;
 109 }
 110
 111 MODULE_LICENSE("GPL");