linux/drivers/clk/mediatek/clk-gate.c
Ricky Liang 95f589814c clk: mediatek: Initialize clk_init_data
The variable init (struct clk_init_data) is allocated on the stack.
We weren't initializing the .flags field, so it contains random junk,
which can cause all kinds of interesting issues when the flags are
parsed by clk_register.

Signed-off-by: Ricky Liang <jcliang@chromium.org>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
2015-05-19 18:40:48 -07:00

138 lines
2.7 KiB
C

/*
* Copyright (c) 2014 MediaTek Inc.
* Author: James Liao <jamesjj.liao@mediatek.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/clkdev.h>
#include "clk-mtk.h"
#include "clk-gate.h"
static int mtk_cg_bit_is_cleared(struct clk_hw *hw)
{
struct mtk_clk_gate *cg = to_clk_gate(hw);
u32 val;
regmap_read(cg->regmap, cg->sta_ofs, &val);
val &= BIT(cg->bit);
return val == 0;
}
static int mtk_cg_bit_is_set(struct clk_hw *hw)
{
struct mtk_clk_gate *cg = to_clk_gate(hw);
u32 val;
regmap_read(cg->regmap, cg->sta_ofs, &val);
val &= BIT(cg->bit);
return val != 0;
}
static void mtk_cg_set_bit(struct clk_hw *hw)
{
struct mtk_clk_gate *cg = to_clk_gate(hw);
regmap_write(cg->regmap, cg->set_ofs, BIT(cg->bit));
}
static void mtk_cg_clr_bit(struct clk_hw *hw)
{
struct mtk_clk_gate *cg = to_clk_gate(hw);
regmap_write(cg->regmap, cg->clr_ofs, BIT(cg->bit));
}
static int mtk_cg_enable(struct clk_hw *hw)
{
mtk_cg_clr_bit(hw);
return 0;
}
static void mtk_cg_disable(struct clk_hw *hw)
{
mtk_cg_set_bit(hw);
}
static int mtk_cg_enable_inv(struct clk_hw *hw)
{
mtk_cg_set_bit(hw);
return 0;
}
static void mtk_cg_disable_inv(struct clk_hw *hw)
{
mtk_cg_clr_bit(hw);
}
const struct clk_ops mtk_clk_gate_ops_setclr = {
.is_enabled = mtk_cg_bit_is_cleared,
.enable = mtk_cg_enable,
.disable = mtk_cg_disable,
};
const struct clk_ops mtk_clk_gate_ops_setclr_inv = {
.is_enabled = mtk_cg_bit_is_set,
.enable = mtk_cg_enable_inv,
.disable = mtk_cg_disable_inv,
};
struct clk *mtk_clk_register_gate(
const char *name,
const char *parent_name,
struct regmap *regmap,
int set_ofs,
int clr_ofs,
int sta_ofs,
u8 bit,
const struct clk_ops *ops)
{
struct mtk_clk_gate *cg;
struct clk *clk;
struct clk_init_data init = {};
cg = kzalloc(sizeof(*cg), GFP_KERNEL);
if (!cg)
return ERR_PTR(-ENOMEM);
init.name = name;
init.flags = CLK_SET_RATE_PARENT;
init.parent_names = parent_name ? &parent_name : NULL;
init.num_parents = parent_name ? 1 : 0;
init.ops = ops;
cg->regmap = regmap;
cg->set_ofs = set_ofs;
cg->clr_ofs = clr_ofs;
cg->sta_ofs = sta_ofs;
cg->bit = bit;
cg->hw.init = &init;
clk = clk_register(NULL, &cg->hw);
if (IS_ERR(clk))
kfree(cg);
return clk;
}