1/*
2 * Copyright (C) 2007 Google, Inc.
3 * Copyright (C) 2012 Intel, Inc.
4 *
5 * This software is licensed under the terms of the GNU General Public
6 * License version 2, as published by the Free Software Foundation, and
7 * may be copied, distributed, and modified under those terms.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 *
14 */
15
16#include <linux/module.h>
17#include <linux/interrupt.h>
18#include <linux/types.h>
19#include <linux/input.h>
20#include <linux/kernel.h>
21#include <linux/platform_device.h>
22#include <linux/slab.h>
23#include <linux/irq.h>
24#include <linux/io.h>
25
26enum {
27	REG_READ        = 0x00,
28	REG_SET_PAGE    = 0x00,
29	REG_LEN         = 0x04,
30	REG_DATA        = 0x08,
31
32	PAGE_NAME       = 0x00000,
33	PAGE_EVBITS     = 0x10000,
34	PAGE_ABSDATA    = 0x20000 | EV_ABS,
35};
36
37struct event_dev {
38	struct input_dev *input;
39	int irq;
40	void __iomem *addr;
41	char name[0];
42};
43
44static irqreturn_t events_interrupt(int irq, void *dev_id)
45{
46	struct event_dev *edev = dev_id;
47	unsigned type, code, value;
48
49	type = __raw_readl(edev->addr + REG_READ);
50	code = __raw_readl(edev->addr + REG_READ);
51	value = __raw_readl(edev->addr + REG_READ);
52
53	input_event(edev->input, type, code, value);
54	input_sync(edev->input);
55	return IRQ_HANDLED;
56}
57
58static void events_import_bits(struct event_dev *edev,
59			unsigned long bits[], unsigned type, size_t count)
60{
61	void __iomem *addr = edev->addr;
62	int i, j;
63	size_t size;
64	uint8_t val;
65
66	__raw_writel(PAGE_EVBITS | type, addr + REG_SET_PAGE);
67
68	size = __raw_readl(addr + REG_LEN) * 8;
69	if (size < count)
70		count = size;
71
72	addr += REG_DATA;
73	for (i = 0; i < count; i += 8) {
74		val = __raw_readb(addr++);
75		for (j = 0; j < 8; j++)
76			if (val & 1 << j)
77				set_bit(i + j, bits);
78	}
79}
80
81static void events_import_abs_params(struct event_dev *edev)
82{
83	struct input_dev *input_dev = edev->input;
84	void __iomem *addr = edev->addr;
85	u32 val[4];
86	int count;
87	int i, j;
88
89	__raw_writel(PAGE_ABSDATA, addr + REG_SET_PAGE);
90
91	count = __raw_readl(addr + REG_LEN) / sizeof(val);
92	if (count > ABS_MAX)
93		count = ABS_MAX;
94
95	for (i = 0; i < count; i++) {
96		if (!test_bit(i, input_dev->absbit))
97			continue;
98
99		for (j = 0; j < ARRAY_SIZE(val); j++) {
100			int offset = (i * ARRAY_SIZE(val) + j) * sizeof(u32);
101			val[j] = __raw_readl(edev->addr + REG_DATA + offset);
102		}
103
104		input_set_abs_params(input_dev, i,
105				     val[0], val[1], val[2], val[3]);
106	}
107}
108
109static int events_probe(struct platform_device *pdev)
110{
111	struct input_dev *input_dev;
112	struct event_dev *edev;
113	struct resource *res;
114	unsigned keymapnamelen;
115	void __iomem *addr;
116	int irq;
117	int i;
118	int error;
119
120	irq = platform_get_irq(pdev, 0);
121	if (irq < 0)
122		return -EINVAL;
123
124	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
125	if (!res)
126		return -EINVAL;
127
128	addr = devm_ioremap(&pdev->dev, res->start, 4096);
129	if (!addr)
130		return -ENOMEM;
131
132	__raw_writel(PAGE_NAME, addr + REG_SET_PAGE);
133	keymapnamelen = __raw_readl(addr + REG_LEN);
134
135	edev = devm_kzalloc(&pdev->dev,
136			    sizeof(struct event_dev) + keymapnamelen + 1,
137			    GFP_KERNEL);
138	if (!edev)
139		return -ENOMEM;
140
141	input_dev = devm_input_allocate_device(&pdev->dev);
142	if (!input_dev)
143		return -ENOMEM;
144
145	edev->input = input_dev;
146	edev->addr = addr;
147	edev->irq = irq;
148
149	for (i = 0; i < keymapnamelen; i++)
150		edev->name[i] = __raw_readb(edev->addr + REG_DATA + i);
151
152	pr_debug("events_probe() keymap=%s\n", edev->name);
153
154	input_dev->name = edev->name;
155	input_dev->id.bustype = BUS_HOST;
156
157	events_import_bits(edev, input_dev->evbit, EV_SYN, EV_MAX);
158	events_import_bits(edev, input_dev->keybit, EV_KEY, KEY_MAX);
159	events_import_bits(edev, input_dev->relbit, EV_REL, REL_MAX);
160	events_import_bits(edev, input_dev->absbit, EV_ABS, ABS_MAX);
161	events_import_bits(edev, input_dev->mscbit, EV_MSC, MSC_MAX);
162	events_import_bits(edev, input_dev->ledbit, EV_LED, LED_MAX);
163	events_import_bits(edev, input_dev->sndbit, EV_SND, SND_MAX);
164	events_import_bits(edev, input_dev->ffbit, EV_FF, FF_MAX);
165	events_import_bits(edev, input_dev->swbit, EV_SW, SW_MAX);
166
167	events_import_abs_params(edev);
168
169	error = devm_request_irq(&pdev->dev, edev->irq, events_interrupt, 0,
170				 "goldfish-events-keypad", edev);
171	if (error)
172		return error;
173
174	error = input_register_device(input_dev);
175	if (error)
176		return error;
177
178	return 0;
179}
180
181static struct platform_driver events_driver = {
182	.probe	= events_probe,
183	.driver	= {
184		.name	= "goldfish_events",
185	},
186};
187
188module_platform_driver(events_driver);
189
190MODULE_AUTHOR("Brian Swetland");
191MODULE_DESCRIPTION("Goldfish Event Device");
192MODULE_LICENSE("GPL");
193