1/*
2 * Samsung S5P/EXYNOS SoC series MIPI CSIS/DSIM DPHY driver
3 *
4 * Copyright (C) 2013 Samsung Electronics Co., Ltd.
5 * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <linux/err.h>
13#include <linux/io.h>
14#include <linux/kernel.h>
15#include <linux/mfd/syscon/exynos4-pmu.h>
16#include <linux/module.h>
17#include <linux/of.h>
18#include <linux/of_address.h>
19#include <linux/phy/phy.h>
20#include <linux/platform_device.h>
21#include <linux/regmap.h>
22#include <linux/spinlock.h>
23#include <linux/mfd/syscon.h>
24
25/* MIPI_PHYn_CONTROL reg. offset (for base address from ioremap): n = 0..1 */
26#define EXYNOS_MIPI_PHY_CONTROL(n)	((n) * 4)
27
28enum exynos_mipi_phy_id {
29	EXYNOS_MIPI_PHY_ID_CSIS0,
30	EXYNOS_MIPI_PHY_ID_DSIM0,
31	EXYNOS_MIPI_PHY_ID_CSIS1,
32	EXYNOS_MIPI_PHY_ID_DSIM1,
33	EXYNOS_MIPI_PHYS_NUM
34};
35
36#define is_mipi_dsim_phy_id(id) \
37	((id) == EXYNOS_MIPI_PHY_ID_DSIM0 || (id) == EXYNOS_MIPI_PHY_ID_DSIM1)
38
39struct exynos_mipi_video_phy {
40	struct video_phy_desc {
41		struct phy *phy;
42		unsigned int index;
43	} phys[EXYNOS_MIPI_PHYS_NUM];
44	spinlock_t slock;
45	void __iomem *regs;
46	struct regmap *regmap;
47};
48
49static int __set_phy_state(struct exynos_mipi_video_phy *state,
50			enum exynos_mipi_phy_id id, unsigned int on)
51{
52	const unsigned int offset = EXYNOS4_MIPI_PHY_CONTROL(id / 2);
53	void __iomem *addr;
54	u32 val, reset;
55
56	if (is_mipi_dsim_phy_id(id))
57		reset = EXYNOS4_MIPI_PHY_MRESETN;
58	else
59		reset = EXYNOS4_MIPI_PHY_SRESETN;
60
61	spin_lock(&state->slock);
62
63	if (!IS_ERR(state->regmap)) {
64		regmap_read(state->regmap, offset, &val);
65		if (on)
66			val |= reset;
67		else
68			val &= ~reset;
69		regmap_write(state->regmap, offset, val);
70		if (on)
71			val |= EXYNOS4_MIPI_PHY_ENABLE;
72		else if (!(val & EXYNOS4_MIPI_PHY_RESET_MASK))
73			val &= ~EXYNOS4_MIPI_PHY_ENABLE;
74		regmap_write(state->regmap, offset, val);
75	} else {
76		addr = state->regs + EXYNOS_MIPI_PHY_CONTROL(id / 2);
77
78		val = readl(addr);
79		if (on)
80			val |= reset;
81		else
82			val &= ~reset;
83		writel(val, addr);
84		/* Clear ENABLE bit only if MRESETN, SRESETN bits are not set */
85		if (on)
86			val |= EXYNOS4_MIPI_PHY_ENABLE;
87		else if (!(val & EXYNOS4_MIPI_PHY_RESET_MASK))
88			val &= ~EXYNOS4_MIPI_PHY_ENABLE;
89
90		writel(val, addr);
91	}
92
93	spin_unlock(&state->slock);
94	return 0;
95}
96
97#define to_mipi_video_phy(desc) \
98	container_of((desc), struct exynos_mipi_video_phy, phys[(desc)->index]);
99
100static int exynos_mipi_video_phy_power_on(struct phy *phy)
101{
102	struct video_phy_desc *phy_desc = phy_get_drvdata(phy);
103	struct exynos_mipi_video_phy *state = to_mipi_video_phy(phy_desc);
104
105	return __set_phy_state(state, phy_desc->index, 1);
106}
107
108static int exynos_mipi_video_phy_power_off(struct phy *phy)
109{
110	struct video_phy_desc *phy_desc = phy_get_drvdata(phy);
111	struct exynos_mipi_video_phy *state = to_mipi_video_phy(phy_desc);
112
113	return __set_phy_state(state, phy_desc->index, 0);
114}
115
116static struct phy *exynos_mipi_video_phy_xlate(struct device *dev,
117					struct of_phandle_args *args)
118{
119	struct exynos_mipi_video_phy *state = dev_get_drvdata(dev);
120
121	if (WARN_ON(args->args[0] >= EXYNOS_MIPI_PHYS_NUM))
122		return ERR_PTR(-ENODEV);
123
124	return state->phys[args->args[0]].phy;
125}
126
127static struct phy_ops exynos_mipi_video_phy_ops = {
128	.power_on	= exynos_mipi_video_phy_power_on,
129	.power_off	= exynos_mipi_video_phy_power_off,
130	.owner		= THIS_MODULE,
131};
132
133static int exynos_mipi_video_phy_probe(struct platform_device *pdev)
134{
135	struct exynos_mipi_video_phy *state;
136	struct device *dev = &pdev->dev;
137	struct phy_provider *phy_provider;
138	unsigned int i;
139
140	state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
141	if (!state)
142		return -ENOMEM;
143
144	state->regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "syscon");
145	if (IS_ERR(state->regmap)) {
146		struct resource *res;
147
148		dev_info(dev, "regmap lookup failed: %ld\n",
149			 PTR_ERR(state->regmap));
150
151		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
152		state->regs = devm_ioremap_resource(dev, res);
153		if (IS_ERR(state->regs))
154			return PTR_ERR(state->regs);
155	}
156
157	dev_set_drvdata(dev, state);
158	spin_lock_init(&state->slock);
159
160	for (i = 0; i < EXYNOS_MIPI_PHYS_NUM; i++) {
161		struct phy *phy = devm_phy_create(dev, NULL,
162						  &exynos_mipi_video_phy_ops);
163		if (IS_ERR(phy)) {
164			dev_err(dev, "failed to create PHY %d\n", i);
165			return PTR_ERR(phy);
166		}
167
168		state->phys[i].phy = phy;
169		state->phys[i].index = i;
170		phy_set_drvdata(phy, &state->phys[i]);
171	}
172
173	phy_provider = devm_of_phy_provider_register(dev,
174					exynos_mipi_video_phy_xlate);
175
176	return PTR_ERR_OR_ZERO(phy_provider);
177}
178
179static const struct of_device_id exynos_mipi_video_phy_of_match[] = {
180	{ .compatible = "samsung,s5pv210-mipi-video-phy" },
181	{ },
182};
183MODULE_DEVICE_TABLE(of, exynos_mipi_video_phy_of_match);
184
185static struct platform_driver exynos_mipi_video_phy_driver = {
186	.probe	= exynos_mipi_video_phy_probe,
187	.driver = {
188		.of_match_table	= exynos_mipi_video_phy_of_match,
189		.name  = "exynos-mipi-video-phy",
190	}
191};
192module_platform_driver(exynos_mipi_video_phy_driver);
193
194MODULE_DESCRIPTION("Samsung S5P/EXYNOS SoC MIPI CSI-2/DSI PHY driver");
195MODULE_AUTHOR("Sylwester Nawrocki <s.nawrocki@samsung.com>");
196MODULE_LICENSE("GPL v2");
197