Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
[linux-2.6] / drivers / input / mouse / pxa930_trkball.c
1 /*
2  * PXA930 track ball mouse driver
3  *
4  * Copyright (C) 2007 Marvell International Ltd.
5  * 2008-02-28: Yong Yao <yaoyong@marvell.com>
6  *             initial version
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 as
10  *  published by the Free Software Foundation.
11  */
12
13 #include <linux/init.h>
14 #include <linux/input.h>
15 #include <linux/version.h>
16 #include <linux/interrupt.h>
17 #include <linux/module.h>
18 #include <linux/platform_device.h>
19 #include <linux/delay.h>
20 #include <linux/io.h>
21
22 #include <mach/hardware.h>
23 #include <mach/pxa930_trkball.h>
24
25 /* Trackball Controller Register Definitions */
26 #define TBCR            (0x000C)
27 #define TBCNTR          (0x0010)
28 #define TBSBC           (0x0014)
29
30 #define TBCR_TBRST      (1 << 1)
31 #define TBCR_TBSB       (1 << 10)
32
33 #define TBCR_Y_FLT(n)   (((n) & 0xf) << 6)
34 #define TBCR_X_FLT(n)   (((n) & 0xf) << 2)
35
36 #define TBCNTR_YM(n)    (((n) >> 24) & 0xff)
37 #define TBCNTR_YP(n)    (((n) >> 16) & 0xff)
38 #define TBCNTR_XM(n)    (((n) >> 8) & 0xff)
39 #define TBCNTR_XP(n)    ((n) & 0xff)
40
41 #define TBSBC_TBSBC     (0x1)
42
43 struct pxa930_trkball {
44         struct pxa930_trkball_platform_data *pdata;
45
46         /* Memory Mapped Register */
47         struct resource *mem;
48         void __iomem *mmio_base;
49
50         struct input_dev *input;
51 };
52
53 static irqreturn_t pxa930_trkball_interrupt(int irq, void *dev_id)
54 {
55         struct pxa930_trkball *trkball = dev_id;
56         struct input_dev *input = trkball->input;
57         int tbcntr, x, y;
58
59         /* According to the spec software must read TBCNTR twice:
60          * if the read value is the same, the reading is valid
61          */
62         tbcntr = __raw_readl(trkball->mmio_base + TBCNTR);
63
64         if (tbcntr == __raw_readl(trkball->mmio_base + TBCNTR)) {
65                 x = (TBCNTR_XP(tbcntr) - TBCNTR_XM(tbcntr)) / 2;
66                 y = (TBCNTR_YP(tbcntr) - TBCNTR_YM(tbcntr)) / 2;
67
68                 input_report_rel(input, REL_X, x);
69                 input_report_rel(input, REL_Y, y);
70                 input_sync(input);
71         }
72
73         __raw_writel(TBSBC_TBSBC, trkball->mmio_base + TBSBC);
74         __raw_writel(0, trkball->mmio_base + TBSBC);
75
76         return IRQ_HANDLED;
77 }
78
79 /* For TBCR, we need to wait for a while to make sure it has been modified. */
80 static int write_tbcr(struct pxa930_trkball *trkball, int v)
81 {
82         int i = 100;
83
84         __raw_writel(v, trkball->mmio_base + TBCR);
85
86         while (--i) {
87                 if (__raw_readl(trkball->mmio_base + TBCR) == v)
88                         break;
89                 msleep(1);
90         }
91
92         if (i == 0) {
93                 pr_err("%s: timed out writing TBCR(%x)!\n", __func__, v);
94                 return -ETIMEDOUT;
95         }
96
97         return 0;
98 }
99
100 static void pxa930_trkball_config(struct pxa930_trkball *trkball)
101 {
102         uint32_t tbcr;
103
104         /* According to spec, need to write the filters of x,y to 0xf first! */
105         tbcr = __raw_readl(trkball->mmio_base + TBCR);
106         write_tbcr(trkball, tbcr | TBCR_X_FLT(0xf) | TBCR_Y_FLT(0xf));
107         write_tbcr(trkball, TBCR_X_FLT(trkball->pdata->x_filter) |
108                             TBCR_Y_FLT(trkball->pdata->y_filter));
109
110         /* According to spec, set TBCR_TBRST first, before clearing it! */
111         tbcr = __raw_readl(trkball->mmio_base + TBCR);
112         write_tbcr(trkball, tbcr | TBCR_TBRST);
113         write_tbcr(trkball, tbcr & ~TBCR_TBRST);
114
115         __raw_writel(TBSBC_TBSBC, trkball->mmio_base + TBSBC);
116         __raw_writel(0, trkball->mmio_base + TBSBC);
117
118         pr_debug("%s: final TBCR=%x!\n", __func__,
119                  __raw_readl(trkball->mmio_base + TBCR));
120 }
121
122 static int pxa930_trkball_open(struct input_dev *dev)
123 {
124         struct pxa930_trkball *trkball = input_get_drvdata(dev);
125
126         pxa930_trkball_config(trkball);
127
128         return 0;
129 }
130
131 static void pxa930_trkball_disable(struct pxa930_trkball *trkball)
132 {
133         uint32_t tbcr = __raw_readl(trkball->mmio_base + TBCR);
134
135         /* Held in reset, gate the 32-KHz input clock off */
136         write_tbcr(trkball, tbcr | TBCR_TBRST);
137 }
138
139 static void pxa930_trkball_close(struct input_dev *dev)
140 {
141         struct pxa930_trkball *trkball = input_get_drvdata(dev);
142
143         pxa930_trkball_disable(trkball);
144 }
145
146 static int __devinit pxa930_trkball_probe(struct platform_device *pdev)
147 {
148         struct pxa930_trkball *trkball;
149         struct input_dev *input;
150         struct resource *res;
151         int irq, error;
152
153         irq = platform_get_irq(pdev, 0);
154         if (irq < 0) {
155                 dev_err(&pdev->dev, "failed to get trkball irq\n");
156                 return -ENXIO;
157         }
158
159         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
160         if (!res) {
161                 dev_err(&pdev->dev, "failed to get register memory\n");
162                 return -ENXIO;
163         }
164
165         trkball = kzalloc(sizeof(struct pxa930_trkball), GFP_KERNEL);
166         if (!trkball)
167                 return -ENOMEM;
168
169         trkball->pdata = pdev->dev.platform_data;
170         if (!trkball->pdata) {
171                 dev_err(&pdev->dev, "no platform data defined\n");
172                 error = -EINVAL;
173                 goto failed;
174         }
175
176         trkball->mmio_base = ioremap_nocache(res->start, resource_size(res));
177         if (!trkball->mmio_base) {
178                 dev_err(&pdev->dev, "failed to ioremap registers\n");
179                 error = -ENXIO;
180                 goto failed;
181         }
182
183         /* held the module in reset, will be enabled in open() */
184         pxa930_trkball_disable(trkball);
185
186         error = request_irq(irq, pxa930_trkball_interrupt, IRQF_DISABLED,
187                             pdev->name, trkball);
188         if (error) {
189                 dev_err(&pdev->dev, "failed to request irq: %d\n", error);
190                 goto failed_free_io;
191         }
192
193         platform_set_drvdata(pdev, trkball);
194
195         input = input_allocate_device();
196         if (!input) {
197                 dev_err(&pdev->dev, "failed to allocate input device\n");
198                 error = -ENOMEM;
199                 goto failed_free_irq;
200         }
201
202         input->name = pdev->name;
203         input->id.bustype = BUS_HOST;
204         input->open = pxa930_trkball_open;
205         input->close = pxa930_trkball_close;
206         input->dev.parent = &pdev->dev;
207         input_set_drvdata(input, trkball);
208
209         trkball->input = input;
210
211         input_set_capability(input, EV_REL, REL_X);
212         input_set_capability(input, EV_REL, REL_Y);
213
214         error = input_register_device(input);
215         if (error) {
216                 dev_err(&pdev->dev, "unable to register input device\n");
217                 goto failed_free_input;
218         }
219
220         return 0;
221
222 failed_free_input:
223         input_free_device(input);
224 failed_free_irq:
225         free_irq(irq, trkball);
226 failed_free_io:
227         iounmap(trkball->mmio_base);
228 failed:
229         kfree(trkball);
230         return error;
231 }
232
233 static int __devexit pxa930_trkball_remove(struct platform_device *pdev)
234 {
235         struct pxa930_trkball *trkball = platform_get_drvdata(pdev);
236         int irq = platform_get_irq(pdev, 0);
237
238         input_unregister_device(trkball->input);
239         free_irq(irq, trkball);
240         iounmap(trkball->mmio_base);
241         kfree(trkball);
242
243         return 0;
244 }
245
246 static struct platform_driver pxa930_trkball_driver = {
247         .driver         = {
248                 .name   = "pxa930-trkball",
249         },
250         .probe          = pxa930_trkball_probe,
251         .remove         = __devexit_p(pxa930_trkball_remove),
252 };
253
254 static int __init pxa930_trkball_init(void)
255 {
256         return platform_driver_register(&pxa930_trkball_driver);
257 }
258
259 static void __exit pxa930_trkball_exit(void)
260 {
261         platform_driver_unregister(&pxa930_trkball_driver);
262 }
263
264 module_init(pxa930_trkball_init);
265 module_exit(pxa930_trkball_exit);
266
267 MODULE_AUTHOR("Yong Yao <yaoyong@marvell.com>");
268 MODULE_DESCRIPTION("PXA930 Trackball Mouse Driver");
269 MODULE_LICENSE("GPL");