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/interrupt.h>
10 #include <linux/io.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 #include <linux/platform_data/bfin_rotary.h>
17
18 #include <asm/portmux.h>
19
20 #define CNT_CONFIG_OFF 0 /* CNT Config Offset */
21 #define CNT_IMASK_OFF 4 /* CNT Interrupt Mask Offset */
22 #define CNT_STATUS_OFF 8 /* CNT Status Offset */
23 #define CNT_COMMAND_OFF 12 /* CNT Command Offset */
24 #define CNT_DEBOUNCE_OFF 16 /* CNT Debounce Offset */
25 #define CNT_COUNTER_OFF 20 /* CNT Counter Offset */
26 #define CNT_MAX_OFF 24 /* CNT Maximum Count Offset */
27 #define CNT_MIN_OFF 28 /* CNT Minimum Count Offset */
28
29 struct bfin_rot {
30 struct input_dev *input;
31 void __iomem *base;
32 int irq;
33 unsigned int up_key;
34 unsigned int down_key;
35 unsigned int button_key;
36 unsigned int rel_code;
37
38 unsigned short mode;
39 unsigned short debounce;
40
41 unsigned short cnt_config;
42 unsigned short cnt_imask;
43 unsigned short cnt_debounce;
44 };
45
report_key_event(struct input_dev * input,int keycode)46 static void report_key_event(struct input_dev *input, int keycode)
47 {
48 /* simulate a press-n-release */
49 input_report_key(input, keycode, 1);
50 input_sync(input);
51 input_report_key(input, keycode, 0);
52 input_sync(input);
53 }
54
report_rotary_event(struct bfin_rot * rotary,int delta)55 static void report_rotary_event(struct bfin_rot *rotary, int delta)
56 {
57 struct input_dev *input = rotary->input;
58
59 if (rotary->up_key) {
60 report_key_event(input,
61 delta > 0 ? rotary->up_key : rotary->down_key);
62 } else {
63 input_report_rel(input, rotary->rel_code, delta);
64 input_sync(input);
65 }
66 }
67
bfin_rotary_isr(int irq,void * dev_id)68 static irqreturn_t bfin_rotary_isr(int irq, void *dev_id)
69 {
70 struct bfin_rot *rotary = dev_id;
71 int delta;
72
73 switch (readw(rotary->base + CNT_STATUS_OFF)) {
74
75 case ICII:
76 break;
77
78 case UCII:
79 case DCII:
80 delta = readl(rotary->base + CNT_COUNTER_OFF);
81 if (delta)
82 report_rotary_event(rotary, delta);
83 break;
84
85 case CZMII:
86 report_key_event(rotary->input, rotary->button_key);
87 break;
88
89 default:
90 break;
91 }
92
93 writew(W1LCNT_ZERO, rotary->base + CNT_COMMAND_OFF); /* Clear COUNTER */
94 writew(-1, rotary->base + CNT_STATUS_OFF); /* Clear STATUS */
95
96 return IRQ_HANDLED;
97 }
98
bfin_rotary_open(struct input_dev * input)99 static int bfin_rotary_open(struct input_dev *input)
100 {
101 struct bfin_rot *rotary = input_get_drvdata(input);
102 unsigned short val;
103
104 if (rotary->mode & ROT_DEBE)
105 writew(rotary->debounce & DPRESCALE,
106 rotary->base + CNT_DEBOUNCE_OFF);
107
108 writew(rotary->mode & ~CNTE, rotary->base + CNT_CONFIG_OFF);
109
110 val = UCIE | DCIE;
111 if (rotary->button_key)
112 val |= CZMIE;
113 writew(val, rotary->base + CNT_IMASK_OFF);
114
115 writew(rotary->mode | CNTE, rotary->base + CNT_CONFIG_OFF);
116
117 return 0;
118 }
119
bfin_rotary_close(struct input_dev * input)120 static void bfin_rotary_close(struct input_dev *input)
121 {
122 struct bfin_rot *rotary = input_get_drvdata(input);
123
124 writew(0, rotary->base + CNT_CONFIG_OFF);
125 writew(0, rotary->base + CNT_IMASK_OFF);
126 }
127
bfin_rotary_free_action(void * data)128 static void bfin_rotary_free_action(void *data)
129 {
130 peripheral_free_list(data);
131 }
132
bfin_rotary_probe(struct platform_device * pdev)133 static int bfin_rotary_probe(struct platform_device *pdev)
134 {
135 struct device *dev = &pdev->dev;
136 const struct bfin_rotary_platform_data *pdata = dev_get_platdata(dev);
137 struct bfin_rot *rotary;
138 struct resource *res;
139 struct input_dev *input;
140 int error;
141
142 /* Basic validation */
143 if ((pdata->rotary_up_key && !pdata->rotary_down_key) ||
144 (!pdata->rotary_up_key && pdata->rotary_down_key)) {
145 return -EINVAL;
146 }
147
148 if (pdata->pin_list) {
149 error = peripheral_request_list(pdata->pin_list,
150 dev_name(&pdev->dev));
151 if (error) {
152 dev_err(dev, "requesting peripherals failed: %d\n",
153 error);
154 return error;
155 }
156
157 error = devm_add_action(dev, bfin_rotary_free_action,
158 pdata->pin_list);
159 if (error) {
160 dev_err(dev, "setting cleanup action failed: %d\n",
161 error);
162 peripheral_free_list(pdata->pin_list);
163 return error;
164 }
165 }
166
167 rotary = devm_kzalloc(dev, sizeof(struct bfin_rot), GFP_KERNEL);
168 if (!rotary)
169 return -ENOMEM;
170
171 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
172 rotary->base = devm_ioremap_resource(dev, res);
173 if (IS_ERR(rotary->base))
174 return PTR_ERR(rotary->base);
175
176 input = devm_input_allocate_device(dev);
177 if (!input)
178 return -ENOMEM;
179
180 rotary->input = input;
181
182 rotary->up_key = pdata->rotary_up_key;
183 rotary->down_key = pdata->rotary_down_key;
184 rotary->button_key = pdata->rotary_button_key;
185 rotary->rel_code = pdata->rotary_rel_code;
186
187 rotary->mode = pdata->mode;
188 rotary->debounce = pdata->debounce;
189
190 input->name = pdev->name;
191 input->phys = "bfin-rotary/input0";
192 input->dev.parent = &pdev->dev;
193
194 input_set_drvdata(input, rotary);
195
196 input->id.bustype = BUS_HOST;
197 input->id.vendor = 0x0001;
198 input->id.product = 0x0001;
199 input->id.version = 0x0100;
200
201 input->open = bfin_rotary_open;
202 input->close = bfin_rotary_close;
203
204 if (rotary->up_key) {
205 __set_bit(EV_KEY, input->evbit);
206 __set_bit(rotary->up_key, input->keybit);
207 __set_bit(rotary->down_key, input->keybit);
208 } else {
209 __set_bit(EV_REL, input->evbit);
210 __set_bit(rotary->rel_code, input->relbit);
211 }
212
213 if (rotary->button_key) {
214 __set_bit(EV_KEY, input->evbit);
215 __set_bit(rotary->button_key, input->keybit);
216 }
217
218 /* Quiesce the device before requesting irq */
219 bfin_rotary_close(input);
220
221 rotary->irq = platform_get_irq(pdev, 0);
222 if (rotary->irq < 0) {
223 dev_err(dev, "No rotary IRQ specified\n");
224 return -ENOENT;
225 }
226
227 error = devm_request_irq(dev, rotary->irq, bfin_rotary_isr,
228 0, dev_name(dev), rotary);
229 if (error) {
230 dev_err(dev, "unable to claim irq %d; error %d\n",
231 rotary->irq, error);
232 return error;
233 }
234
235 error = input_register_device(input);
236 if (error) {
237 dev_err(dev, "unable to register input device (%d)\n", error);
238 return error;
239 }
240
241 platform_set_drvdata(pdev, rotary);
242 device_init_wakeup(&pdev->dev, 1);
243
244 return 0;
245 }
246
bfin_rotary_suspend(struct device * dev)247 static int __maybe_unused bfin_rotary_suspend(struct device *dev)
248 {
249 struct platform_device *pdev = to_platform_device(dev);
250 struct bfin_rot *rotary = platform_get_drvdata(pdev);
251
252 rotary->cnt_config = readw(rotary->base + CNT_CONFIG_OFF);
253 rotary->cnt_imask = readw(rotary->base + CNT_IMASK_OFF);
254 rotary->cnt_debounce = readw(rotary->base + CNT_DEBOUNCE_OFF);
255
256 if (device_may_wakeup(&pdev->dev))
257 enable_irq_wake(rotary->irq);
258
259 return 0;
260 }
261
bfin_rotary_resume(struct device * dev)262 static int __maybe_unused bfin_rotary_resume(struct device *dev)
263 {
264 struct platform_device *pdev = to_platform_device(dev);
265 struct bfin_rot *rotary = platform_get_drvdata(pdev);
266
267 writew(rotary->cnt_debounce, rotary->base + CNT_DEBOUNCE_OFF);
268 writew(rotary->cnt_imask, rotary->base + CNT_IMASK_OFF);
269 writew(rotary->cnt_config & ~CNTE, rotary->base + CNT_CONFIG_OFF);
270
271 if (device_may_wakeup(&pdev->dev))
272 disable_irq_wake(rotary->irq);
273
274 if (rotary->cnt_config & CNTE)
275 writew(rotary->cnt_config, rotary->base + CNT_CONFIG_OFF);
276
277 return 0;
278 }
279
280 static SIMPLE_DEV_PM_OPS(bfin_rotary_pm_ops,
281 bfin_rotary_suspend, bfin_rotary_resume);
282
283 static struct platform_driver bfin_rotary_device_driver = {
284 .probe = bfin_rotary_probe,
285 .driver = {
286 .name = "bfin-rotary",
287 .pm = &bfin_rotary_pm_ops,
288 },
289 };
290 module_platform_driver(bfin_rotary_device_driver);
291
292 MODULE_LICENSE("GPL");
293 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
294 MODULE_DESCRIPTION("Rotary Counter driver for Blackfin Processors");
295 MODULE_ALIAS("platform:bfin-rotary");
296