tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Driver for the enhanced rotary controller on pxa930 and pxa935
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/interrupt.h>
13#include <linux/input.h>
14#include <linux/platform_device.h>
15#include <linux/io.h>
16
17#include <mach/pxa930_rotary.h>
18
19#define SBCR (0x04)
20#define ERCR (0x0c)
21
22#define SBCR_ERSB (1 << 5)
23
24struct pxa930_rotary {
25 struct input_dev *input_dev;
26 void __iomem *mmio_base;
27 int last_ercr;
28
29 struct pxa930_rotary_platform_data *pdata;
30};
31
32static void clear_sbcr(struct pxa930_rotary *r)
33{
34 uint32_t sbcr = __raw_readl(r->mmio_base + SBCR);
35
36 __raw_writel(sbcr | SBCR_ERSB, r->mmio_base + SBCR);
37 __raw_writel(sbcr & ~SBCR_ERSB, r->mmio_base + SBCR);
38}
39
40static irqreturn_t rotary_irq(int irq, void *dev_id)
41{
42 struct pxa930_rotary *r = dev_id;
43 struct pxa930_rotary_platform_data *pdata = r->pdata;
44 int ercr, delta, key;
45
46 ercr = __raw_readl(r->mmio_base + ERCR) & 0xf;
47 clear_sbcr(r);
48
49 delta = ercr - r->last_ercr;
50 if (delta == 0)
51 return IRQ_HANDLED;
52
53 r->last_ercr = ercr;
54
55 if (pdata->up_key && pdata->down_key) {
56 key = (delta > 0) ? pdata->up_key : pdata->down_key;
57 input_report_key(r->input_dev, key, 1);
58 input_sync(r->input_dev);
59 input_report_key(r->input_dev, key, 0);
60 } else
61 input_report_rel(r->input_dev, pdata->rel_code, delta);
62
63 input_sync(r->input_dev);
64
65 return IRQ_HANDLED;
66}
67
68static int pxa930_rotary_open(struct input_dev *dev)
69{
70 struct pxa930_rotary *r = input_get_drvdata(dev);
71
72 clear_sbcr(r);
73
74 return 0;
75}
76
77static void pxa930_rotary_close(struct input_dev *dev)
78{
79 struct pxa930_rotary *r = input_get_drvdata(dev);
80
81 clear_sbcr(r);
82}
83
84static int __devinit pxa930_rotary_probe(struct platform_device *pdev)
85{
86 struct pxa930_rotary_platform_data *pdata = pdev->dev.platform_data;
87 struct pxa930_rotary *r;
88 struct input_dev *input_dev;
89 struct resource *res;
90 int irq;
91 int err;
92
93 irq = platform_get_irq(pdev, 0);
94 if (irq < 0) {
95 dev_err(&pdev->dev, "no irq for rotary controller\n");
96 return -ENXIO;
97 }
98
99 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
100 if (!res) {
101 dev_err(&pdev->dev, "no I/O memory defined\n");
102 return -ENXIO;
103 }
104
105 if (!pdata) {
106 dev_err(&pdev->dev, "no platform data defined\n");
107 return -EINVAL;
108 }
109
110 r = kzalloc(sizeof(struct pxa930_rotary), GFP_KERNEL);
111 if (!r)
112 return -ENOMEM;
113
114 r->mmio_base = ioremap_nocache(res->start, resource_size(res));
115 if (r->mmio_base == NULL) {
116 dev_err(&pdev->dev, "failed to remap IO memory\n");
117 err = -ENXIO;
118 goto failed_free;
119 }
120
121 r->pdata = pdata;
122 platform_set_drvdata(pdev, r);
123
124 /* allocate and register the input device */
125 input_dev = input_allocate_device();
126 if (!input_dev) {
127 dev_err(&pdev->dev, "failed to allocate input device\n");
128 err = -ENOMEM;
129 goto failed_free_io;
130 }
131
132 input_dev->name = pdev->name;
133 input_dev->id.bustype = BUS_HOST;
134 input_dev->open = pxa930_rotary_open;
135 input_dev->close = pxa930_rotary_close;
136 input_dev->dev.parent = &pdev->dev;
137
138 if (pdata->up_key && pdata->down_key) {
139 __set_bit(pdata->up_key, input_dev->keybit);
140 __set_bit(pdata->down_key, input_dev->keybit);
141 __set_bit(EV_KEY, input_dev->evbit);
142 } else {
143 __set_bit(pdata->rel_code, input_dev->relbit);
144 __set_bit(EV_REL, input_dev->evbit);
145 }
146
147 r->input_dev = input_dev;
148 input_set_drvdata(input_dev, r);
149
150 err = request_irq(irq, rotary_irq, IRQF_DISABLED,
151 "enhanced rotary", r);
152 if (err) {
153 dev_err(&pdev->dev, "failed to request IRQ\n");
154 goto failed_free_input;
155 }
156
157 err = input_register_device(input_dev);
158 if (err) {
159 dev_err(&pdev->dev, "failed to register input device\n");
160 goto failed_free_irq;
161 }
162
163 return 0;
164
165failed_free_irq:
166 free_irq(irq, r);
167failed_free_input:
168 input_free_device(input_dev);
169failed_free_io:
170 iounmap(r->mmio_base);
171failed_free:
172 kfree(r);
173 return err;
174}
175
176static int __devexit pxa930_rotary_remove(struct platform_device *pdev)
177{
178 struct pxa930_rotary *r = platform_get_drvdata(pdev);
179
180 free_irq(platform_get_irq(pdev, 0), r);
181 input_unregister_device(r->input_dev);
182 iounmap(r->mmio_base);
183 platform_set_drvdata(pdev, NULL);
184 kfree(r);
185
186 return 0;
187}
188
189static struct platform_driver pxa930_rotary_driver = {
190 .driver = {
191 .name = "pxa930-rotary",
192 .owner = THIS_MODULE,
193 },
194 .probe = pxa930_rotary_probe,
195 .remove = __devexit_p(pxa930_rotary_remove),
196};
197
198static int __init pxa930_rotary_init(void)
199{
200 return platform_driver_register(&pxa930_rotary_driver);
201}
202module_init(pxa930_rotary_init);
203
204static void __exit pxa930_rotary_exit(void)
205{
206 platform_driver_unregister(&pxa930_rotary_driver);
207}
208module_exit(pxa930_rotary_exit);
209
210MODULE_LICENSE("GPL");
211MODULE_DESCRIPTION("Driver for PXA93x Enhanced Rotary Controller");
212MODULE_AUTHOR("Yao Yong <yaoyong@marvell.com>");