1/**
  2 * dwc3-of-simple.c - OF glue layer for simple integrations
  3 *
  4 * Copyright (c) 2015 Texas Instruments Incorporated - http://www.ti.com
  5 *
  6 * Author: Felipe Balbi <balbi@ti.com>
  7 *
  8 * This program is free software: you can redistribute it and/or modify
  9 * it under the terms of the GNU General Public License version 2  of
 10 * the License as published by the Free Software Foundation.
 11 *
 12 * This program is distributed in the hope that it will be useful,
 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15 * GNU General Public License for more details.
 16 *
 17 * This is a combination of the old dwc3-qcom.c by Ivan T. Ivanov
 18 * <iivanov@mm-sol.com> and the original patch adding support for Xilinx' SoC
 19 * by Subbaraya Sundeep Bhatta <subbaraya.sundeep.bhatta@xilinx.com>
 20 */
 21
 22#include <linux/module.h>
 23#include <linux/kernel.h>
 24#include <linux/slab.h>
 25#include <linux/platform_device.h>
 26#include <linux/dma-mapping.h>
 27#include <linux/clk.h>
 28#include <linux/clk-provider.h>
 29#include <linux/of.h>
 30#include <linux/of_platform.h>
 31#include <linux/pm_runtime.h>
 32
 33struct dwc3_of_simple {
 34	struct device		*dev;
 35	struct clk		**clks;
 36	int			num_clocks;
 37};
 38
 39static int dwc3_of_simple_probe(struct platform_device *pdev)
 40{
 41	struct dwc3_of_simple	*simple;
 42	struct device		*dev = &pdev->dev;
 43	struct device_node	*np = dev->of_node;
 44
 45	unsigned int		count;
 46	int			ret;
 47	int			i;
 48
 49	simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
 50	if (!simple)
 51		return -ENOMEM;
 52
 53	count = of_clk_get_parent_count(np);
 54	if (!count)
 55		return -ENOENT;
 56
 57	simple->num_clocks = count;
 58
 59	simple->clks = devm_kcalloc(dev, simple->num_clocks,
 60			sizeof(struct clk *), GFP_KERNEL);
 61	if (!simple->clks)
 62		return -ENOMEM;
 63
 64	simple->dev = dev;
 65
 66	for (i = 0; i < simple->num_clocks; i++) {
 67		struct clk	*clk;
 68
 69		clk = of_clk_get(np, i);
 70		if (IS_ERR(clk)) {
 71			while (--i >= 0)
 72				clk_put(simple->clks[i]);
 73			return PTR_ERR(clk);
 74		}
 75
 76		ret = clk_prepare_enable(clk);
 77		if (ret < 0) {
 78			while (--i >= 0) {
 79				clk_disable_unprepare(simple->clks[i]);
 80				clk_put(simple->clks[i]);
 81			}
 82			clk_put(clk);
 83
 84			return ret;
 85		}
 86
 87		simple->clks[i] = clk;
 88	}
 89
 90	ret = of_platform_populate(np, NULL, NULL, dev);
 91	if (ret) {
 92		for (i = 0; i < simple->num_clocks; i++) {
 93			clk_disable_unprepare(simple->clks[i]);
 94			clk_put(simple->clks[i]);
 95		}
 96
 97		return ret;
 98	}
 99
100	pm_runtime_set_active(dev);
101	pm_runtime_enable(dev);
102	pm_runtime_get_sync(dev);
103
104	return 0;
105}
106
107static int dwc3_of_simple_remove(struct platform_device *pdev)
108{
109	struct dwc3_of_simple	*simple = platform_get_drvdata(pdev);
110	struct device		*dev = &pdev->dev;
111	int			i;
112
113	for (i = 0; i < simple->num_clocks; i++) {
114		clk_unprepare(simple->clks[i]);
115		clk_put(simple->clks[i]);
116	}
117
118	of_platform_depopulate(dev);
119
120	pm_runtime_put_sync(dev);
121	pm_runtime_disable(dev);
122
123	return 0;
124}
125
126#ifdef CONFIG_PM
127static int dwc3_of_simple_runtime_suspend(struct device *dev)
128{
129	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
130	int			i;
131
132	for (i = 0; i < simple->num_clocks; i++)
133		clk_disable(simple->clks[i]);
134
135	return 0;
136}
137
138static int dwc3_of_simple_runtime_resume(struct device *dev)
139{
140	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
141	int			ret;
142	int			i;
143
144	for (i = 0; i < simple->num_clocks; i++) {
145		ret = clk_enable(simple->clks[i]);
146		if (ret < 0) {
147			while (--i >= 0)
148				clk_disable(simple->clks[i]);
149			return ret;
150		}
151	}
152
153	return 0;
154}
155#endif
156
157static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
158	SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
159			dwc3_of_simple_runtime_resume, NULL)
160};
161
162static const struct of_device_id of_dwc3_simple_match[] = {
163	{ .compatible = "qcom,dwc3" },
164	{ .compatible = "xlnx,zynqmp-dwc3" },
165	{ /* Sentinel */ }
166};
167MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
168
169static struct platform_driver dwc3_of_simple_driver = {
170	.probe		= dwc3_of_simple_probe,
171	.remove		= dwc3_of_simple_remove,
172	.driver		= {
173		.name	= "dwc3-of-simple",
174		.of_match_table = of_dwc3_simple_match,
175	},
176};
177
178module_platform_driver(dwc3_of_simple_driver);
179MODULE_LICENSE("GPL v2");
180MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
181MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");