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