drivers/clk/actions/owl-divider.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // OWL divider clock driver
   4 //
   5 // Copyright (c) 2014 Actions Semi Inc.
   6 // Author: David Liu <liuwei@actions-semi.com>
   7 //
   8 // Copyright (c) 2018 Linaro Ltd.
   9 // Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
  10
  11 #include <linux/clk-provider.h>
  12 #include <linux/regmap.h>
  13
  14 #include "owl-divider.h"
  15
  16 long owl_divider_helper_round_rate(struct owl_clk_common *common,
  17                                 const struct owl_divider_hw *div_hw,
  18                                 unsigned long rate,
  19                                 unsigned long *parent_rate)
  20 {
  21         return divider_round_rate(&common->hw, rate, parent_rate,
  22                                   div_hw->table, div_hw->width,
  23                                   div_hw->div_flags);
  24 }
  25
  26 static long owl_divider_round_rate(struct clk_hw *hw, unsigned long rate,
  27                                 unsigned long *parent_rate)
  28 {
  29         struct owl_divider *div = hw_to_owl_divider(hw);
  30
  31         return owl_divider_helper_round_rate(&div->common, &div->div_hw,
  32                                              rate, parent_rate);
  33 }
  34
  35 unsigned long owl_divider_helper_recalc_rate(struct owl_clk_common *common,
  36                                          const struct owl_divider_hw *div_hw,
  37                                          unsigned long parent_rate)
  38 {
  39         unsigned long val;
  40         unsigned int reg;
  41
  42         regmap_read(common->regmap, div_hw->reg, &reg);
  43         val = reg >> div_hw->shift;
  44         val &= (1 << div_hw->width) - 1;
  45
  46         return divider_recalc_rate(&common->hw, parent_rate,
  47                                    val, div_hw->table,
  48                                    div_hw->div_flags,
  49                                    div_hw->width);
  50 }
  51
  52 static unsigned long owl_divider_recalc_rate(struct clk_hw *hw,
  53                                           unsigned long parent_rate)
  54 {
  55         struct owl_divider *div = hw_to_owl_divider(hw);
  56
  57         return owl_divider_helper_recalc_rate(&div->common,
  58                                               &div->div_hw, parent_rate);
  59 }
  60
  61 int owl_divider_helper_set_rate(const struct owl_clk_common *common,
  62                                 const struct owl_divider_hw *div_hw,
  63                                 unsigned long rate,
  64                                 unsigned long parent_rate)
  65 {
  66         unsigned long val;
  67         unsigned int reg;
  68
  69         val = divider_get_val(rate, parent_rate, div_hw->table,
  70                               div_hw->width, 0);
  71
  72         regmap_read(common->regmap, div_hw->reg, &reg);
  73         reg &= ~GENMASK(div_hw->width + div_hw->shift - 1, div_hw->shift);
  74
  75         regmap_write(common->regmap, div_hw->reg,
  76                           reg | (val << div_hw->shift));
  77
  78         return 0;
  79 }
  80
  81 static int owl_divider_set_rate(struct clk_hw *hw, unsigned long rate,
  82                                 unsigned long parent_rate)
  83 {
  84         struct owl_divider *div = hw_to_owl_divider(hw);
  85
  86         return owl_divider_helper_set_rate(&div->common, &div->div_hw,
  87                                         rate, parent_rate);
  88 }
  89
  90 const struct clk_ops owl_divider_ops = {
  91         .recalc_rate = owl_divider_recalc_rate,
  92         .round_rate = owl_divider_round_rate,
  93         .set_rate = owl_divider_set_rate,
  94 };