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