1/*
  2 * Samsung EXYNOS SoC series Display Port PHY driver
  3 *
  4 * Copyright (C) 2013 Samsung Electronics Co., Ltd.
  5 * Author: Jingoo Han <jg1.han@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/io.h>
 13#include <linux/kernel.h>
 14#include <linux/module.h>
 15#include <linux/of.h>
 16#include <linux/of_address.h>
 17#include <linux/phy/phy.h>
 18#include <linux/platform_device.h>
 19
 20/* DPTX_PHY_CONTROL register */
 21#define EXYNOS_DPTX_PHY_ENABLE		(1 << 0)
 22
 23struct exynos_dp_video_phy {
 24	void __iomem *regs;
 25};
 26
 27static int __set_phy_state(struct exynos_dp_video_phy *state, unsigned int on)
 28{
 29	u32 reg;
 30
 31	reg = readl(state->regs);
 32	if (on)
 33		reg |= EXYNOS_DPTX_PHY_ENABLE;
 34	else
 35		reg &= ~EXYNOS_DPTX_PHY_ENABLE;
 36	writel(reg, state->regs);
 37
 38	return 0;
 39}
 40
 41static int exynos_dp_video_phy_power_on(struct phy *phy)
 42{
 43	struct exynos_dp_video_phy *state = phy_get_drvdata(phy);
 44
 45	return __set_phy_state(state, 1);
 46}
 47
 48static int exynos_dp_video_phy_power_off(struct phy *phy)
 49{
 50	struct exynos_dp_video_phy *state = phy_get_drvdata(phy);
 51
 52	return __set_phy_state(state, 0);
 53}
 54
 55static struct phy_ops exynos_dp_video_phy_ops = {
 56	.power_on	= exynos_dp_video_phy_power_on,
 57	.power_off	= exynos_dp_video_phy_power_off,
 58	.owner		= THIS_MODULE,
 59};
 60
 61static int exynos_dp_video_phy_probe(struct platform_device *pdev)
 62{
 63	struct exynos_dp_video_phy *state;
 64	struct device *dev = &pdev->dev;
 65	struct resource *res;
 66	struct phy_provider *phy_provider;
 67	struct phy *phy;
 68
 69	state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
 70	if (!state)
 71		return -ENOMEM;
 72
 73	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 74
 75	state->regs = devm_ioremap_resource(dev, res);
 76	if (IS_ERR(state->regs))
 77		return PTR_ERR(state->regs);
 78
 79	phy = devm_phy_create(dev, &exynos_dp_video_phy_ops, NULL);
 80	if (IS_ERR(phy)) {
 81		dev_err(dev, "failed to create Display Port PHY\n");
 82		return PTR_ERR(phy);
 83	}
 84	phy_set_drvdata(phy, state);
 85
 86	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 87	if (IS_ERR(phy_provider))
 88		return PTR_ERR(phy_provider);
 89
 90	return 0;
 91}
 92
 93static const struct of_device_id exynos_dp_video_phy_of_match[] = {
 94	{ .compatible = "samsung,exynos5250-dp-video-phy" },
 95	{ },
 96};
 97MODULE_DEVICE_TABLE(of, exynos_dp_video_phy_of_match);
 98
 99static struct platform_driver exynos_dp_video_phy_driver = {
100	.probe	= exynos_dp_video_phy_probe,
101	.driver = {
102		.name	= "exynos-dp-video-phy",
103		.owner	= THIS_MODULE,
104		.of_match_table	= exynos_dp_video_phy_of_match,
105	}
106};
107module_platform_driver(exynos_dp_video_phy_driver);
108
109MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
110MODULE_DESCRIPTION("Samsung EXYNOS SoC DP PHY driver");
111MODULE_LICENSE("GPL v2");