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