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gerrit-public.fairphone.software / kernel / msm-4.9 / 7bccc36544a8b4a7d768f8ccdd6001a52872aca9 / . / drivers / clk / hisilicon / clkgate-separated.c
blob: a47812f56a17bb97d5a98521b67f1ace784ad9a4 [file] [log] [blame]
Haojian Zhuang0aa0c952013-11-13 08:51:23 +0800[diff] [blame]1/*
2 * Hisilicon clock separated gate driver
3 *
4 * Copyright (c) 2012-2013 Hisilicon Limited.
5 * Copyright (c) 2012-2013 Linaro Limited.
6 *
7 * Author: Haojian Zhuang <haojian.zhuang@linaro.org>
8 * Xin Li <li.xin@linaro.org>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
23 *
24 */
25
26#include <linux/kernel.h>
27#include <linux/clk-provider.h>
Haojian Zhuang0aa0c952013-11-13 08:51:23 +0800[diff] [blame]28#include <linux/io.h>
29#include <linux/slab.h>
Haojian Zhuang0aa0c952013-11-13 08:51:23 +0800[diff] [blame]30
31#include "clk.h"
32
33/* clock separated gate register offset */
34#define CLKGATE_SEPERATED_ENABLE 0x0
35#define CLKGATE_SEPERATED_DISABLE 0x4
36#define CLKGATE_SEPERATED_STATUS 0x8
37
38struct clkgate_separated {
39 struct clk_hw hw;
40 void __iomem *enable; /* enable register */
41 u8 bit_idx; /* bits in enable/disable register */
42 u8 flags;
43 spinlock_t *lock;
44};
45
46static int clkgate_separated_enable(struct clk_hw *hw)
47{
48 struct clkgate_separated *sclk;
49 unsigned long flags = 0;
50 u32 reg;
51
52 sclk = container_of(hw, struct clkgate_separated, hw);
53 if (sclk->lock)
54 spin_lock_irqsave(sclk->lock, flags);
55 reg = BIT(sclk->bit_idx);
56 writel_relaxed(reg, sclk->enable);
57 readl_relaxed(sclk->enable + CLKGATE_SEPERATED_STATUS);
58 if (sclk->lock)
59 spin_unlock_irqrestore(sclk->lock, flags);
60 return 0;
61}
62
63static void clkgate_separated_disable(struct clk_hw *hw)
64{
65 struct clkgate_separated *sclk;
66 unsigned long flags = 0;
67 u32 reg;
68
69 sclk = container_of(hw, struct clkgate_separated, hw);
70 if (sclk->lock)
71 spin_lock_irqsave(sclk->lock, flags);
72 reg = BIT(sclk->bit_idx);
73 writel_relaxed(reg, sclk->enable + CLKGATE_SEPERATED_DISABLE);
74 readl_relaxed(sclk->enable + CLKGATE_SEPERATED_STATUS);
75 if (sclk->lock)
76 spin_unlock_irqrestore(sclk->lock, flags);
77}
78
79static int clkgate_separated_is_enabled(struct clk_hw *hw)
80{
81 struct clkgate_separated *sclk;
82 u32 reg;
83
84 sclk = container_of(hw, struct clkgate_separated, hw);
85 reg = readl_relaxed(sclk->enable + CLKGATE_SEPERATED_STATUS);
86 reg &= BIT(sclk->bit_idx);
87
88 return reg ? 1 : 0;
89}
90
91static struct clk_ops clkgate_separated_ops = {
92 .enable = clkgate_separated_enable,
93 .disable = clkgate_separated_disable,
94 .is_enabled = clkgate_separated_is_enabled,
95};
96
97struct clk *hisi_register_clkgate_sep(struct device *dev, const char *name,
98 const char *parent_name,
99 unsigned long flags,
100 void __iomem *reg, u8 bit_idx,
101 u8 clk_gate_flags, spinlock_t *lock)
102{
103 struct clkgate_separated *sclk;
104 struct clk *clk;
105 struct clk_init_data init;
106
107 sclk = kzalloc(sizeof(*sclk), GFP_KERNEL);
108 if (!sclk) {
109 pr_err("%s: fail to allocate separated gated clk\n", __func__);
110 return ERR_PTR(-ENOMEM);
111 }
112
113 init.name = name;
114 init.ops = &clkgate_separated_ops;
115 init.flags = flags | CLK_IS_BASIC;
116 init.parent_names = (parent_name ? &parent_name : NULL);
117 init.num_parents = (parent_name ? 1 : 0);
118
119 sclk->enable = reg + CLKGATE_SEPERATED_ENABLE;
120 sclk->bit_idx = bit_idx;
121 sclk->flags = clk_gate_flags;
122 sclk->hw.init = &init;
123
124 clk = clk_register(dev, &sclk->hw);
125 if (IS_ERR(clk))
126 kfree(sclk);
127 return clk;
128}