1 /*
2 * Rotary counter driver for Analog Devices Blackfin Processors
3 *
4 * Copyright 2008-2009 Analog Devices Inc.
5 * Licensed under the GPL-2 or later.
6 */
7
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/interrupt.h>
11 #include <linux/irq.h>
12 #include <linux/pm.h>
13 #include <linux/platform_device.h>
14 #include <linux/input.h>
15 #include <linux/slab.h>
16
17 #include <asm/portmux.h>
18 #include <asm/bfin_rotary.h>
19
20 static const u16 per_cnt[] = {
21 P_CNT_CUD,
22 P_CNT_CDG,
23 P_CNT_CZM,
24 0
25 };
26
27 struct bfin_rot {
28 struct input_dev *input;
29 int irq;
30 unsigned int up_key;
31 unsigned int down_key;
32 unsigned int button_key;
33 unsigned int rel_code;
34 unsigned short cnt_config;
35 unsigned short cnt_imask;
36 unsigned short cnt_debounce;
37 };
38
report_key_event(struct input_dev * input,int keycode)39 static void report_key_event(struct input_dev *input, int keycode)
40 {
41 /* simulate a press-n-release */
42 input_report_key(input, keycode, 1);
43 input_sync(input);
44 input_report_key(input, keycode, 0);
45 input_sync(input);
46 }
47
report_rotary_event(struct bfin_rot * rotary,int delta)48 static void report_rotary_event(struct bfin_rot *rotary, int delta)
49 {
50 struct input_dev *input = rotary->input;
51
52 if (rotary->up_key) {
53 report_key_event(input,
54 delta > 0 ? rotary->up_key : rotary->down_key);
55 } else {
56 input_report_rel(input, rotary->rel_code, delta);
57 input_sync(input);
58 }
59 }
60
bfin_rotary_isr(int irq,void * dev_id)61 static irqreturn_t bfin_rotary_isr(int irq, void *dev_id)
62 {
63 struct platform_device *pdev = dev_id;
64 struct bfin_rot *rotary = platform_get_drvdata(pdev);
65 int delta;
66
67 switch (bfin_read_CNT_STATUS()) {
68
69 case ICII:
70 break;
71
72 case UCII:
73 case DCII:
74 delta = bfin_read_CNT_COUNTER();
75 if (delta)
76 report_rotary_event(rotary, delta);
77 break;
78
79 case CZMII:
80 report_key_event(rotary->input, rotary->button_key);
81 break;
82
83 default:
84 break;
85 }
86
87 bfin_write_CNT_COMMAND(W1LCNT_ZERO); /* Clear COUNTER */
88 bfin_write_CNT_STATUS(-1); /* Clear STATUS */
89
90 return IRQ_HANDLED;
91 }
92
bfin_rotary_probe(struct platform_device * pdev)93 static int bfin_rotary_probe(struct platform_device *pdev)
94 {
95 struct bfin_rotary_platform_data *pdata = pdev->dev.platform_data;
96 struct bfin_rot *rotary;
97 struct input_dev *input;
98 int error;
99
100 /* Basic validation */
101 if ((pdata->rotary_up_key && !pdata->rotary_down_key) ||
102 (!pdata->rotary_up_key && pdata->rotary_down_key)) {
103 return -EINVAL;
104 }
105
106 error = peripheral_request_list(per_cnt, dev_name(&pdev->dev));
107 if (error) {
108 dev_err(&pdev->dev, "requesting peripherals failed\n");
109 return error;
110 }
111
112 rotary = kzalloc(sizeof(struct bfin_rot), GFP_KERNEL);
113 input = input_allocate_device();
114 if (!rotary || !input) {
115 error = -ENOMEM;
116 goto out1;
117 }
118
119 rotary->input = input;
120
121 rotary->up_key = pdata->rotary_up_key;
122 rotary->down_key = pdata->rotary_down_key;
123 rotary->button_key = pdata->rotary_button_key;
124 rotary->rel_code = pdata->rotary_rel_code;
125
126 error = rotary->irq = platform_get_irq(pdev, 0);
127 if (error < 0)
128 goto out1;
129
130 input->name = pdev->name;
131 input->phys = "bfin-rotary/input0";
132 input->dev.parent = &pdev->dev;
133
134 input_set_drvdata(input, rotary);
135
136 input->id.bustype = BUS_HOST;
137 input->id.vendor = 0x0001;
138 input->id.product = 0x0001;
139 input->id.version = 0x0100;
140
141 if (rotary->up_key) {
142 __set_bit(EV_KEY, input->evbit);
143 __set_bit(rotary->up_key, input->keybit);
144 __set_bit(rotary->down_key, input->keybit);
145 } else {
146 __set_bit(EV_REL, input->evbit);
147 __set_bit(rotary->rel_code, input->relbit);
148 }
149
150 if (rotary->button_key) {
151 __set_bit(EV_KEY, input->evbit);
152 __set_bit(rotary->button_key, input->keybit);
153 }
154
155 error = request_irq(rotary->irq, bfin_rotary_isr,
156 0, dev_name(&pdev->dev), pdev);
157 if (error) {
158 dev_err(&pdev->dev,
159 "unable to claim irq %d; error %d\n",
160 rotary->irq, error);
161 goto out1;
162 }
163
164 error = input_register_device(input);
165 if (error) {
166 dev_err(&pdev->dev,
167 "unable to register input device (%d)\n", error);
168 goto out2;
169 }
170
171 if (pdata->rotary_button_key)
172 bfin_write_CNT_IMASK(CZMIE);
173
174 if (pdata->mode & ROT_DEBE)
175 bfin_write_CNT_DEBOUNCE(pdata->debounce & DPRESCALE);
176
177 if (pdata->mode)
178 bfin_write_CNT_CONFIG(bfin_read_CNT_CONFIG() |
179 (pdata->mode & ~CNTE));
180
181 bfin_write_CNT_IMASK(bfin_read_CNT_IMASK() | UCIE | DCIE);
182 bfin_write_CNT_CONFIG(bfin_read_CNT_CONFIG() | CNTE);
183
184 platform_set_drvdata(pdev, rotary);
185 device_init_wakeup(&pdev->dev, 1);
186
187 return 0;
188
189 out2:
190 free_irq(rotary->irq, pdev);
191 out1:
192 input_free_device(input);
193 kfree(rotary);
194 peripheral_free_list(per_cnt);
195
196 return error;
197 }
198
bfin_rotary_remove(struct platform_device * pdev)199 static int bfin_rotary_remove(struct platform_device *pdev)
200 {
201 struct bfin_rot *rotary = platform_get_drvdata(pdev);
202
203 bfin_write_CNT_CONFIG(0);
204 bfin_write_CNT_IMASK(0);
205
206 free_irq(rotary->irq, pdev);
207 input_unregister_device(rotary->input);
208 peripheral_free_list(per_cnt);
209
210 kfree(rotary);
211 platform_set_drvdata(pdev, NULL);
212
213 return 0;
214 }
215
216 #ifdef CONFIG_PM
bfin_rotary_suspend(struct device * dev)217 static int bfin_rotary_suspend(struct device *dev)
218 {
219 struct platform_device *pdev = to_platform_device(dev);
220 struct bfin_rot *rotary = platform_get_drvdata(pdev);
221
222 rotary->cnt_config = bfin_read_CNT_CONFIG();
223 rotary->cnt_imask = bfin_read_CNT_IMASK();
224 rotary->cnt_debounce = bfin_read_CNT_DEBOUNCE();
225
226 if (device_may_wakeup(&pdev->dev))
227 enable_irq_wake(rotary->irq);
228
229 return 0;
230 }
231
bfin_rotary_resume(struct device * dev)232 static int bfin_rotary_resume(struct device *dev)
233 {
234 struct platform_device *pdev = to_platform_device(dev);
235 struct bfin_rot *rotary = platform_get_drvdata(pdev);
236
237 bfin_write_CNT_DEBOUNCE(rotary->cnt_debounce);
238 bfin_write_CNT_IMASK(rotary->cnt_imask);
239 bfin_write_CNT_CONFIG(rotary->cnt_config & ~CNTE);
240
241 if (device_may_wakeup(&pdev->dev))
242 disable_irq_wake(rotary->irq);
243
244 if (rotary->cnt_config & CNTE)
245 bfin_write_CNT_CONFIG(rotary->cnt_config);
246
247 return 0;
248 }
249
250 static const struct dev_pm_ops bfin_rotary_pm_ops = {
251 .suspend = bfin_rotary_suspend,
252 .resume = bfin_rotary_resume,
253 };
254 #endif
255
256 static struct platform_driver bfin_rotary_device_driver = {
257 .probe = bfin_rotary_probe,
258 .remove = bfin_rotary_remove,
259 .driver = {
260 .name = "bfin-rotary",
261 .owner = THIS_MODULE,
262 #ifdef CONFIG_PM
263 .pm = &bfin_rotary_pm_ops,
264 #endif
265 },
266 };
267 module_platform_driver(bfin_rotary_device_driver);
268
269 MODULE_LICENSE("GPL");
270 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
271 MODULE_DESCRIPTION("Rotary Counter driver for Blackfin Processors");
272 MODULE_ALIAS("platform:bfin-rotary");
273