drivers/clk/qcom/clk-regmap-mux.c

   1 /*
   2  * Copyright (c) 2014, The Linux Foundation. All rights reserved.
   3  *
   4  * This software is licensed under the terms of the GNU General Public
   5  * License version 2, as published by the Free Software Foundation, and
   6  * may be copied, distributed, and modified under those terms.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/bitops.h>
  16 #include <linux/regmap.h>
  17 #include <linux/export.h>
  18
  19 #include "clk-regmap-mux.h"
  20
  21 static inline struct clk_regmap_mux *to_clk_regmap_mux(struct clk_hw *hw)
  22 {
  23         return container_of(to_clk_regmap(hw), struct clk_regmap_mux, clkr);
  24 }
  25
  26 static u8 mux_get_parent(struct clk_hw *hw)
  27 {
  28         struct clk_regmap_mux *mux = to_clk_regmap_mux(hw);
  29         struct clk_regmap *clkr = to_clk_regmap(hw);
  30         unsigned int mask = GENMASK(mux->width - 1, 0);
  31         unsigned int val;
  32
  33         regmap_read(clkr->regmap, mux->reg, &val);
  34
  35         val >>= mux->shift;
  36         val &= mask;
  37
  38         return val;
  39 }
  40
  41 static int mux_set_parent(struct clk_hw *hw, u8 index)
  42 {
  43         struct clk_regmap_mux *mux = to_clk_regmap_mux(hw);
  44         struct clk_regmap *clkr = to_clk_regmap(hw);
  45         unsigned int mask = GENMASK(mux->width + mux->shift - 1, mux->shift);
  46         unsigned int val;
  47
  48         val = index;
  49         val <<= mux->shift;
  50
  51         return regmap_update_bits(clkr->regmap, mux->reg, mask, val);
  52 }
  53
  54 const struct clk_ops clk_regmap_mux_closest_ops = {
  55         .get_parent = mux_get_parent,
  56         .set_parent = mux_set_parent,
  57         .determine_rate = __clk_mux_determine_rate_closest,
  58 };
  59 EXPORT_SYMBOL_GPL(clk_regmap_mux_closest_ops);