drivers/clk/imx/clk-fixup-mux.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2013 Freescale Semiconductor, Inc.
   4  */
   5
   6 #include <linux/bits.h>
   7 #include <linux/clk-provider.h>
   8 #include <linux/err.h>
   9 #include <linux/io.h>
  10 #include <linux/slab.h>
  11 #include "clk.h"
  12
  13 /**
  14  * struct clk_fixup_mux - imx integer fixup multiplexer clock
  15  * @mux: the parent class
  16  * @ops: pointer to clk_ops of parent class
  17  * @fixup: a hook to fixup the write value
  18  *
  19  * The imx fixup multiplexer clock is a subclass of basic clk_mux
  20  * with an addtional fixup hook.
  21  */
  22 struct clk_fixup_mux {
  23         struct clk_mux mux;
  24         const struct clk_ops *ops;
  25         void (*fixup)(u32 *val);
  26 };
  27
  28 static inline struct clk_fixup_mux *to_clk_fixup_mux(struct clk_hw *hw)
  29 {
  30         struct clk_mux *mux = to_clk_mux(hw);
  31
  32         return container_of(mux, struct clk_fixup_mux, mux);
  33 }
  34
  35 static u8 clk_fixup_mux_get_parent(struct clk_hw *hw)
  36 {
  37         struct clk_fixup_mux *fixup_mux = to_clk_fixup_mux(hw);
  38
  39         return fixup_mux->ops->get_parent(&fixup_mux->mux.hw);
  40 }
  41
  42 static int clk_fixup_mux_set_parent(struct clk_hw *hw, u8 index)
  43 {
  44         struct clk_fixup_mux *fixup_mux = to_clk_fixup_mux(hw);
  45         struct clk_mux *mux = to_clk_mux(hw);
  46         unsigned long flags;
  47         u32 val;
  48
  49         spin_lock_irqsave(mux->lock, flags);
  50
  51         val = readl(mux->reg);
  52         val &= ~(mux->mask << mux->shift);
  53         val |= index << mux->shift;
  54         fixup_mux->fixup(&val);
  55         writel(val, mux->reg);
  56
  57         spin_unlock_irqrestore(mux->lock, flags);
  58
  59         return 0;
  60 }
  61
  62 static const struct clk_ops clk_fixup_mux_ops = {
  63         .get_parent = clk_fixup_mux_get_parent,
  64         .set_parent = clk_fixup_mux_set_parent,
  65 };
  66
  67 struct clk_hw *imx_clk_hw_fixup_mux(const char *name, void __iomem *reg,
  68                               u8 shift, u8 width, const char * const *parents,
  69                               int num_parents, void (*fixup)(u32 *val))
  70 {
  71         struct clk_fixup_mux *fixup_mux;
  72         struct clk_hw *hw;
  73         struct clk_init_data init;
  74         int ret;
  75
  76         if (!fixup)
  77                 return ERR_PTR(-EINVAL);
  78
  79         fixup_mux = kzalloc(sizeof(*fixup_mux), GFP_KERNEL);
  80         if (!fixup_mux)
  81                 return ERR_PTR(-ENOMEM);
  82
  83         init.name = name;
  84         init.ops = &clk_fixup_mux_ops;
  85         init.parent_names = parents;
  86         init.num_parents = num_parents;
  87         init.flags = 0;
  88
  89         fixup_mux->mux.reg = reg;
  90         fixup_mux->mux.shift = shift;
  91         fixup_mux->mux.mask = BIT(width) - 1;
  92         fixup_mux->mux.lock = &imx_ccm_lock;
  93         fixup_mux->mux.hw.init = &init;
  94         fixup_mux->ops = &clk_mux_ops;
  95         fixup_mux->fixup = fixup;
  96
  97         hw = &fixup_mux->mux.hw;
  98
  99         ret = clk_hw_register(NULL, hw);
 100         if (ret) {
 101                 kfree(fixup_mux);
 102                 return ERR_PTR(ret);
 103         }
 104
 105         return hw;
 106 }