1/*
2 * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
15 */
16
17#include <linux/clk.h>
18#include <linux/clk-provider.h>
19#include <linux/export.h>
20#include <linux/slab.h>
21#include <linux/err.h>
22
23#include "clk.h"
24
25static u8 clk_periph_get_parent(struct clk_hw *hw)
26{
27	struct tegra_clk_periph *periph = to_clk_periph(hw);
28	const struct clk_ops *mux_ops = periph->mux_ops;
29	struct clk_hw *mux_hw = &periph->mux.hw;
30
31	mux_hw->clk = hw->clk;
32
33	return mux_ops->get_parent(mux_hw);
34}
35
36static int clk_periph_set_parent(struct clk_hw *hw, u8 index)
37{
38	struct tegra_clk_periph *periph = to_clk_periph(hw);
39	const struct clk_ops *mux_ops = periph->mux_ops;
40	struct clk_hw *mux_hw = &periph->mux.hw;
41
42	mux_hw->clk = hw->clk;
43
44	return mux_ops->set_parent(mux_hw, index);
45}
46
47static unsigned long clk_periph_recalc_rate(struct clk_hw *hw,
48					    unsigned long parent_rate)
49{
50	struct tegra_clk_periph *periph = to_clk_periph(hw);
51	const struct clk_ops *div_ops = periph->div_ops;
52	struct clk_hw *div_hw = &periph->divider.hw;
53
54	div_hw->clk = hw->clk;
55
56	return div_ops->recalc_rate(div_hw, parent_rate);
57}
58
59static long clk_periph_round_rate(struct clk_hw *hw, unsigned long rate,
60				  unsigned long *prate)
61{
62	struct tegra_clk_periph *periph = to_clk_periph(hw);
63	const struct clk_ops *div_ops = periph->div_ops;
64	struct clk_hw *div_hw = &periph->divider.hw;
65
66	div_hw->clk = hw->clk;
67
68	return div_ops->round_rate(div_hw, rate, prate);
69}
70
71static int clk_periph_set_rate(struct clk_hw *hw, unsigned long rate,
72			       unsigned long parent_rate)
73{
74	struct tegra_clk_periph *periph = to_clk_periph(hw);
75	const struct clk_ops *div_ops = periph->div_ops;
76	struct clk_hw *div_hw = &periph->divider.hw;
77
78	div_hw->clk = hw->clk;
79
80	return div_ops->set_rate(div_hw, rate, parent_rate);
81}
82
83static int clk_periph_is_enabled(struct clk_hw *hw)
84{
85	struct tegra_clk_periph *periph = to_clk_periph(hw);
86	const struct clk_ops *gate_ops = periph->gate_ops;
87	struct clk_hw *gate_hw = &periph->gate.hw;
88
89	gate_hw->clk = hw->clk;
90
91	return gate_ops->is_enabled(gate_hw);
92}
93
94static int clk_periph_enable(struct clk_hw *hw)
95{
96	struct tegra_clk_periph *periph = to_clk_periph(hw);
97	const struct clk_ops *gate_ops = periph->gate_ops;
98	struct clk_hw *gate_hw = &periph->gate.hw;
99
100	gate_hw->clk = hw->clk;
101
102	return gate_ops->enable(gate_hw);
103}
104
105static void clk_periph_disable(struct clk_hw *hw)
106{
107	struct tegra_clk_periph *periph = to_clk_periph(hw);
108	const struct clk_ops *gate_ops = periph->gate_ops;
109	struct clk_hw *gate_hw = &periph->gate.hw;
110
111	gate_ops->disable(gate_hw);
112}
113
114const struct clk_ops tegra_clk_periph_ops = {
115	.get_parent = clk_periph_get_parent,
116	.set_parent = clk_periph_set_parent,
117	.recalc_rate = clk_periph_recalc_rate,
118	.round_rate = clk_periph_round_rate,
119	.set_rate = clk_periph_set_rate,
120	.is_enabled = clk_periph_is_enabled,
121	.enable = clk_periph_enable,
122	.disable = clk_periph_disable,
123};
124
125static const struct clk_ops tegra_clk_periph_nodiv_ops = {
126	.get_parent = clk_periph_get_parent,
127	.set_parent = clk_periph_set_parent,
128	.is_enabled = clk_periph_is_enabled,
129	.enable = clk_periph_enable,
130	.disable = clk_periph_disable,
131};
132
133static const struct clk_ops tegra_clk_periph_no_gate_ops = {
134	.get_parent = clk_periph_get_parent,
135	.set_parent = clk_periph_set_parent,
136	.recalc_rate = clk_periph_recalc_rate,
137	.round_rate = clk_periph_round_rate,
138	.set_rate = clk_periph_set_rate,
139};
140
141static struct clk *_tegra_clk_register_periph(const char *name,
142			const char **parent_names, int num_parents,
143			struct tegra_clk_periph *periph,
144			void __iomem *clk_base, u32 offset,
145			unsigned long flags)
146{
147	struct clk *clk;
148	struct clk_init_data init;
149	struct tegra_clk_periph_regs *bank;
150	bool div = !(periph->gate.flags & TEGRA_PERIPH_NO_DIV);
151
152	if (periph->gate.flags & TEGRA_PERIPH_NO_DIV) {
153		flags |= CLK_SET_RATE_PARENT;
154		init.ops = &tegra_clk_periph_nodiv_ops;
155	} else if (periph->gate.flags & TEGRA_PERIPH_NO_GATE)
156		init.ops = &tegra_clk_periph_no_gate_ops;
157	else
158		init.ops = &tegra_clk_periph_ops;
159
160	init.name = name;
161	init.flags = flags;
162	init.parent_names = parent_names;
163	init.num_parents = num_parents;
164
165	bank = get_reg_bank(periph->gate.clk_num);
166	if (!bank)
167		return ERR_PTR(-EINVAL);
168
169	/* Data in .init is copied by clk_register(), so stack variable OK */
170	periph->hw.init = &init;
171	periph->magic = TEGRA_CLK_PERIPH_MAGIC;
172	periph->mux.reg = clk_base + offset;
173	periph->divider.reg = div ? (clk_base + offset) : NULL;
174	periph->gate.clk_base = clk_base;
175	periph->gate.regs = bank;
176	periph->gate.enable_refcnt = periph_clk_enb_refcnt;
177
178	clk = clk_register(NULL, &periph->hw);
179	if (IS_ERR(clk))
180		return clk;
181
182	periph->mux.hw.clk = clk;
183	periph->divider.hw.clk = div ? clk : NULL;
184	periph->gate.hw.clk = clk;
185
186	return clk;
187}
188
189struct clk *tegra_clk_register_periph(const char *name,
190		const char **parent_names, int num_parents,
191		struct tegra_clk_periph *periph, void __iomem *clk_base,
192		u32 offset, unsigned long flags)
193{
194	return _tegra_clk_register_periph(name, parent_names, num_parents,
195			periph, clk_base, offset, flags);
196}
197
198struct clk *tegra_clk_register_periph_nodiv(const char *name,
199		const char **parent_names, int num_parents,
200		struct tegra_clk_periph *periph, void __iomem *clk_base,
201		u32 offset)
202{
203	periph->gate.flags |= TEGRA_PERIPH_NO_DIV;
204	return _tegra_clk_register_periph(name, parent_names, num_parents,
205			periph, clk_base, offset, CLK_SET_RATE_PARENT);
206}
207