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/init.h>
18 #include <linux/interrupt.h>
19 #include <linux/types.h>
20 #include <linux/input.h>
21 #include <linux/kernel.h>
22 #include <linux/platform_device.h>
23 #include <linux/irq.h>
24 #include <linux/io.h>
25 #include <linux/acpi.h>
26
27 enum {
28 REG_READ = 0x00,
29 REG_SET_PAGE = 0x00,
30 REG_LEN = 0x04,
31 REG_DATA = 0x08,
32
33 PAGE_NAME = 0x00000,
34 PAGE_EVBITS = 0x10000,
35 PAGE_ABSDATA = 0x20000 | EV_ABS,
36 };
37
38 struct event_dev {
39 struct input_dev *input;
40 int irq;
41 void __iomem *addr;
42 char name[0];
43 };
44
rotary_interrupt(int irq,void * dev_id)45 static irqreturn_t rotary_interrupt(int irq, void *dev_id)
46 {
47 struct event_dev *edev = dev_id;
48 unsigned type, code, value;
49
50 type = __raw_readl(edev->addr + REG_READ);
51 code = __raw_readl(edev->addr + REG_READ);
52 value = __raw_readl(edev->addr + REG_READ);
53
54 input_event(edev->input, type, code, value);
55 return IRQ_HANDLED;
56 }
57
rotary_import_bits(struct event_dev * edev,unsigned long bits[],unsigned type,size_t count)58 static void rotary_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
rotary_import_abs_params(struct event_dev * edev)81 static void rotary_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
rotary_probe(struct platform_device * pdev)109 static int rotary_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("rotary_probe() keymap=%s\n", edev->name);
153
154 input_dev->name = edev->name;
155 input_dev->id.bustype = BUS_HOST;
156 rotary_import_bits(edev, input_dev->evbit, EV_SYN, EV_MAX);
157 rotary_import_bits(edev, input_dev->relbit, EV_REL, REL_MAX);
158 rotary_import_bits(edev, input_dev->absbit, EV_ABS, ABS_MAX);
159
160 rotary_import_abs_params(edev);
161
162 error = devm_request_irq(&pdev->dev, edev->irq, rotary_interrupt, 0,
163 "goldfish-rotary", edev);
164 if (error)
165 return error;
166
167 error = input_register_device(input_dev);
168 if (error)
169 return error;
170
171 return 0;
172 }
173
174 static const struct of_device_id goldfish_rotary_of_match[] = {
175 { .compatible = "generic,goldfish-rotary", },
176 {},
177 };
178 MODULE_DEVICE_TABLE(of, goldfish_rotary_of_match);
179
180 static const struct acpi_device_id goldfish_rotary_acpi_match[] = {
181 { "GFSH0008", 0 },
182 { },
183 };
184 MODULE_DEVICE_TABLE(acpi, goldfish_rotary_acpi_match);
185
186 static struct platform_driver rotary_driver = {
187 .probe = rotary_probe,
188 .driver = {
189 .owner = THIS_MODULE,
190 .name = "goldfish_rotary",
191 .of_match_table = goldfish_rotary_of_match,
192 .acpi_match_table = ACPI_PTR(goldfish_rotary_acpi_match),
193 },
194 };
195
196 module_platform_driver(rotary_driver);
197
198 MODULE_AUTHOR("Nimrod Gileadi");
199 MODULE_DESCRIPTION("Goldfish Rotary Encoder Device");
200 MODULE_LICENSE("GPL");
201