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