1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * PXA930 track ball mouse driver
4 *
5 * Copyright (C) 2007 Marvell International Ltd.
6 * 2008-02-28: Yong Yao <yaoyong@marvell.com>
7 * initial version
8 */
9
10 #include <linux/input.h>
11 #include <linux/interrupt.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/delay.h>
15 #include <linux/io.h>
16 #include <linux/slab.h>
17
18 #include <mach/hardware.h>
19 #include <linux/platform_data/mouse-pxa930_trkball.h>
20
21 /* Trackball Controller Register Definitions */
22 #define TBCR (0x000C)
23 #define TBCNTR (0x0010)
24 #define TBSBC (0x0014)
25
26 #define TBCR_TBRST (1 << 1)
27 #define TBCR_TBSB (1 << 10)
28
29 #define TBCR_Y_FLT(n) (((n) & 0xf) << 6)
30 #define TBCR_X_FLT(n) (((n) & 0xf) << 2)
31
32 #define TBCNTR_YM(n) (((n) >> 24) & 0xff)
33 #define TBCNTR_YP(n) (((n) >> 16) & 0xff)
34 #define TBCNTR_XM(n) (((n) >> 8) & 0xff)
35 #define TBCNTR_XP(n) ((n) & 0xff)
36
37 #define TBSBC_TBSBC (0x1)
38
39 struct pxa930_trkball {
40 struct pxa930_trkball_platform_data *pdata;
41
42 /* Memory Mapped Register */
43 struct resource *mem;
44 void __iomem *mmio_base;
45
46 struct input_dev *input;
47 };
48
pxa930_trkball_interrupt(int irq,void * dev_id)49 static irqreturn_t pxa930_trkball_interrupt(int irq, void *dev_id)
50 {
51 struct pxa930_trkball *trkball = dev_id;
52 struct input_dev *input = trkball->input;
53 int tbcntr, x, y;
54
55 /* According to the spec software must read TBCNTR twice:
56 * if the read value is the same, the reading is valid
57 */
58 tbcntr = __raw_readl(trkball->mmio_base + TBCNTR);
59
60 if (tbcntr == __raw_readl(trkball->mmio_base + TBCNTR)) {
61 x = (TBCNTR_XP(tbcntr) - TBCNTR_XM(tbcntr)) / 2;
62 y = (TBCNTR_YP(tbcntr) - TBCNTR_YM(tbcntr)) / 2;
63
64 input_report_rel(input, REL_X, x);
65 input_report_rel(input, REL_Y, y);
66 input_sync(input);
67 }
68
69 __raw_writel(TBSBC_TBSBC, trkball->mmio_base + TBSBC);
70 __raw_writel(0, trkball->mmio_base + TBSBC);
71
72 return IRQ_HANDLED;
73 }
74
75 /* For TBCR, we need to wait for a while to make sure it has been modified. */
write_tbcr(struct pxa930_trkball * trkball,int v)76 static int write_tbcr(struct pxa930_trkball *trkball, int v)
77 {
78 int i = 100;
79
80 __raw_writel(v, trkball->mmio_base + TBCR);
81
82 while (--i) {
83 if (__raw_readl(trkball->mmio_base + TBCR) == v)
84 break;
85 msleep(1);
86 }
87
88 if (i == 0) {
89 pr_err("%s: timed out writing TBCR(%x)!\n", __func__, v);
90 return -ETIMEDOUT;
91 }
92
93 return 0;
94 }
95
pxa930_trkball_config(struct pxa930_trkball * trkball)96 static void pxa930_trkball_config(struct pxa930_trkball *trkball)
97 {
98 uint32_t tbcr;
99
100 /* According to spec, need to write the filters of x,y to 0xf first! */
101 tbcr = __raw_readl(trkball->mmio_base + TBCR);
102 write_tbcr(trkball, tbcr | TBCR_X_FLT(0xf) | TBCR_Y_FLT(0xf));
103 write_tbcr(trkball, TBCR_X_FLT(trkball->pdata->x_filter) |
104 TBCR_Y_FLT(trkball->pdata->y_filter));
105
106 /* According to spec, set TBCR_TBRST first, before clearing it! */
107 tbcr = __raw_readl(trkball->mmio_base + TBCR);
108 write_tbcr(trkball, tbcr | TBCR_TBRST);
109 write_tbcr(trkball, tbcr & ~TBCR_TBRST);
110
111 __raw_writel(TBSBC_TBSBC, trkball->mmio_base + TBSBC);
112 __raw_writel(0, trkball->mmio_base + TBSBC);
113
114 pr_debug("%s: final TBCR=%x!\n", __func__,
115 __raw_readl(trkball->mmio_base + TBCR));
116 }
117
pxa930_trkball_open(struct input_dev * dev)118 static int pxa930_trkball_open(struct input_dev *dev)
119 {
120 struct pxa930_trkball *trkball = input_get_drvdata(dev);
121
122 pxa930_trkball_config(trkball);
123
124 return 0;
125 }
126
pxa930_trkball_disable(struct pxa930_trkball * trkball)127 static void pxa930_trkball_disable(struct pxa930_trkball *trkball)
128 {
129 uint32_t tbcr = __raw_readl(trkball->mmio_base + TBCR);
130
131 /* Held in reset, gate the 32-KHz input clock off */
132 write_tbcr(trkball, tbcr | TBCR_TBRST);
133 }
134
pxa930_trkball_close(struct input_dev * dev)135 static void pxa930_trkball_close(struct input_dev *dev)
136 {
137 struct pxa930_trkball *trkball = input_get_drvdata(dev);
138
139 pxa930_trkball_disable(trkball);
140 }
141
pxa930_trkball_probe(struct platform_device * pdev)142 static int pxa930_trkball_probe(struct platform_device *pdev)
143 {
144 struct pxa930_trkball *trkball;
145 struct input_dev *input;
146 struct resource *res;
147 int irq, error;
148
149 irq = platform_get_irq(pdev, 0);
150 if (irq < 0)
151 return -ENXIO;
152
153 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
154 if (!res) {
155 dev_err(&pdev->dev, "failed to get register memory\n");
156 return -ENXIO;
157 }
158
159 trkball = kzalloc(sizeof(struct pxa930_trkball), GFP_KERNEL);
160 if (!trkball)
161 return -ENOMEM;
162
163 trkball->pdata = dev_get_platdata(&pdev->dev);
164 if (!trkball->pdata) {
165 dev_err(&pdev->dev, "no platform data defined\n");
166 error = -EINVAL;
167 goto failed;
168 }
169
170 trkball->mmio_base = ioremap(res->start, resource_size(res));
171 if (!trkball->mmio_base) {
172 dev_err(&pdev->dev, "failed to ioremap registers\n");
173 error = -ENXIO;
174 goto failed;
175 }
176
177 /* held the module in reset, will be enabled in open() */
178 pxa930_trkball_disable(trkball);
179
180 error = request_irq(irq, pxa930_trkball_interrupt, 0,
181 pdev->name, trkball);
182 if (error) {
183 dev_err(&pdev->dev, "failed to request irq: %d\n", error);
184 goto failed_free_io;
185 }
186
187 platform_set_drvdata(pdev, trkball);
188
189 input = input_allocate_device();
190 if (!input) {
191 dev_err(&pdev->dev, "failed to allocate input device\n");
192 error = -ENOMEM;
193 goto failed_free_irq;
194 }
195
196 input->name = pdev->name;
197 input->id.bustype = BUS_HOST;
198 input->open = pxa930_trkball_open;
199 input->close = pxa930_trkball_close;
200 input->dev.parent = &pdev->dev;
201 input_set_drvdata(input, trkball);
202
203 trkball->input = input;
204
205 input_set_capability(input, EV_REL, REL_X);
206 input_set_capability(input, EV_REL, REL_Y);
207
208 error = input_register_device(input);
209 if (error) {
210 dev_err(&pdev->dev, "unable to register input device\n");
211 goto failed_free_input;
212 }
213
214 return 0;
215
216 failed_free_input:
217 input_free_device(input);
218 failed_free_irq:
219 free_irq(irq, trkball);
220 failed_free_io:
221 iounmap(trkball->mmio_base);
222 failed:
223 kfree(trkball);
224 return error;
225 }
226
pxa930_trkball_remove(struct platform_device * pdev)227 static int pxa930_trkball_remove(struct platform_device *pdev)
228 {
229 struct pxa930_trkball *trkball = platform_get_drvdata(pdev);
230 int irq = platform_get_irq(pdev, 0);
231
232 input_unregister_device(trkball->input);
233 free_irq(irq, trkball);
234 iounmap(trkball->mmio_base);
235 kfree(trkball);
236
237 return 0;
238 }
239
240 static struct platform_driver pxa930_trkball_driver = {
241 .driver = {
242 .name = "pxa930-trkball",
243 },
244 .probe = pxa930_trkball_probe,
245 .remove = pxa930_trkball_remove,
246 };
247 module_platform_driver(pxa930_trkball_driver);
248
249 MODULE_AUTHOR("Yong Yao <yaoyong@marvell.com>");
250 MODULE_DESCRIPTION("PXA930 Trackball Mouse Driver");
251 MODULE_LICENSE("GPL");
252