1/*
  2 * Copyright (C) 2013 Freescale Semiconductor, Inc.
  3 *
  4 * The code contained herein is licensed under the GNU General Public
  5 * License. You may obtain a copy of the GNU General Public License
  6 * Version 2 or later at the following locations:
  7 *
  8 * http://www.opensource.org/licenses/gpl-license.html
  9 * http://www.gnu.org/copyleft/gpl.html
 10 */
 11
 12#include <linux/clk-provider.h>
 13#include <linux/err.h>
 14#include <linux/io.h>
 15#include <linux/slab.h>
 16#include "clk.h"
 17
 18#define to_clk_mux(_hw) container_of(_hw, struct clk_mux, hw)
 19
 20/**
 21 * struct clk_fixup_mux - imx integer fixup multiplexer clock
 22 * @mux: the parent class
 23 * @ops: pointer to clk_ops of parent class
 24 * @fixup: a hook to fixup the write value
 25 *
 26 * The imx fixup multiplexer clock is a subclass of basic clk_mux
 27 * with an addtional fixup hook.
 28 */
 29struct clk_fixup_mux {
 30	struct clk_mux mux;
 31	const struct clk_ops *ops;
 32	void (*fixup)(u32 *val);
 33};
 34
 35static inline struct clk_fixup_mux *to_clk_fixup_mux(struct clk_hw *hw)
 36{
 37	struct clk_mux *mux = to_clk_mux(hw);
 38
 39	return container_of(mux, struct clk_fixup_mux, mux);
 40}
 41
 42static u8 clk_fixup_mux_get_parent(struct clk_hw *hw)
 43{
 44	struct clk_fixup_mux *fixup_mux = to_clk_fixup_mux(hw);
 45
 46	return fixup_mux->ops->get_parent(&fixup_mux->mux.hw);
 47}
 48
 49static int clk_fixup_mux_set_parent(struct clk_hw *hw, u8 index)
 50{
 51	struct clk_fixup_mux *fixup_mux = to_clk_fixup_mux(hw);
 52	struct clk_mux *mux = to_clk_mux(hw);
 53	unsigned long flags = 0;
 54	u32 val;
 55
 56	spin_lock_irqsave(mux->lock, flags);
 57
 58	val = readl(mux->reg);
 59	val &= ~(mux->mask << mux->shift);
 60	val |= index << mux->shift;
 61	fixup_mux->fixup(&val);
 62	writel(val, mux->reg);
 63
 64	spin_unlock_irqrestore(mux->lock, flags);
 65
 66	return 0;
 67}
 68
 69static const struct clk_ops clk_fixup_mux_ops = {
 70	.get_parent = clk_fixup_mux_get_parent,
 71	.set_parent = clk_fixup_mux_set_parent,
 72};
 73
 74struct clk *imx_clk_fixup_mux(const char *name, void __iomem *reg,
 75			      u8 shift, u8 width, const char **parents,
 76			      int num_parents, void (*fixup)(u32 *val))
 77{
 78	struct clk_fixup_mux *fixup_mux;
 79	struct clk *clk;
 80	struct clk_init_data init;
 81
 82	if (!fixup)
 83		return ERR_PTR(-EINVAL);
 84
 85	fixup_mux = kzalloc(sizeof(*fixup_mux), GFP_KERNEL);
 86	if (!fixup_mux)
 87		return ERR_PTR(-ENOMEM);
 88
 89	init.name = name;
 90	init.ops = &clk_fixup_mux_ops;
 91	init.parent_names = parents;
 92	init.num_parents = num_parents;
 93	init.flags = 0;
 94
 95	fixup_mux->mux.reg = reg;
 96	fixup_mux->mux.shift = shift;
 97	fixup_mux->mux.mask = BIT(width) - 1;
 98	fixup_mux->mux.lock = &imx_ccm_lock;
 99	fixup_mux->mux.hw.init = &init;
100	fixup_mux->ops = &clk_mux_ops;
101	fixup_mux->fixup = fixup;
102
103	clk = clk_register(NULL, &fixup_mux->mux.hw);
104	if (IS_ERR(clk))
105		kfree(fixup_mux);
106
107	return clk;
108}