LXR linux/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
  21static 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
  26static 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
  41static 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
  54const 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};
  59EXPORT_SYMBOL_GPL(clk_regmap_mux_closest_ops);
  60