1 /*
2 * DaVinci Key Scan Driver for TI platforms
3 *
4 * Copyright (C) 2009 Texas Instruments, Inc
5 *
6 * Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
7 *
8 * Initial Code: Sandeep Paulraj <s-paulraj@ti.com>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 */
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/interrupt.h>
27 #include <linux/types.h>
28 #include <linux/input.h>
29 #include <linux/kernel.h>
30 #include <linux/delay.h>
31 #include <linux/platform_device.h>
32 #include <linux/errno.h>
33 #include <linux/slab.h>
34
35 #include <asm/irq.h>
36
37 #include <mach/hardware.h>
38 #include <mach/irqs.h>
39 #include <mach/keyscan.h>
40
41 /* Key scan registers */
42 #define DAVINCI_KEYSCAN_KEYCTRL 0x0000
43 #define DAVINCI_KEYSCAN_INTENA 0x0004
44 #define DAVINCI_KEYSCAN_INTFLAG 0x0008
45 #define DAVINCI_KEYSCAN_INTCLR 0x000c
46 #define DAVINCI_KEYSCAN_STRBWIDTH 0x0010
47 #define DAVINCI_KEYSCAN_INTERVAL 0x0014
48 #define DAVINCI_KEYSCAN_CONTTIME 0x0018
49 #define DAVINCI_KEYSCAN_CURRENTST 0x001c
50 #define DAVINCI_KEYSCAN_PREVSTATE 0x0020
51 #define DAVINCI_KEYSCAN_EMUCTRL 0x0024
52 #define DAVINCI_KEYSCAN_IODFTCTRL 0x002c
53
54 /* Key Control Register (KEYCTRL) */
55 #define DAVINCI_KEYSCAN_KEYEN 0x00000001
56 #define DAVINCI_KEYSCAN_PREVMODE 0x00000002
57 #define DAVINCI_KEYSCAN_CHATOFF 0x00000004
58 #define DAVINCI_KEYSCAN_AUTODET 0x00000008
59 #define DAVINCI_KEYSCAN_SCANMODE 0x00000010
60 #define DAVINCI_KEYSCAN_OUTTYPE 0x00000020
61
62 /* Masks for the interrupts */
63 #define DAVINCI_KEYSCAN_INT_CONT 0x00000008
64 #define DAVINCI_KEYSCAN_INT_OFF 0x00000004
65 #define DAVINCI_KEYSCAN_INT_ON 0x00000002
66 #define DAVINCI_KEYSCAN_INT_CHANGE 0x00000001
67 #define DAVINCI_KEYSCAN_INT_ALL 0x0000000f
68
69 struct davinci_ks {
70 struct input_dev *input;
71 struct davinci_ks_platform_data *pdata;
72 int irq;
73 void __iomem *base;
74 resource_size_t pbase;
75 size_t base_size;
76 unsigned short keymap[];
77 };
78
79 /* Initializing the kp Module */
davinci_ks_initialize(struct davinci_ks * davinci_ks)80 static int __init davinci_ks_initialize(struct davinci_ks *davinci_ks)
81 {
82 struct device *dev = &davinci_ks->input->dev;
83 struct davinci_ks_platform_data *pdata = davinci_ks->pdata;
84 u32 matrix_ctrl;
85
86 /* Enable all interrupts */
87 __raw_writel(DAVINCI_KEYSCAN_INT_ALL,
88 davinci_ks->base + DAVINCI_KEYSCAN_INTENA);
89
90 /* Clear interrupts if any */
91 __raw_writel(DAVINCI_KEYSCAN_INT_ALL,
92 davinci_ks->base + DAVINCI_KEYSCAN_INTCLR);
93
94 /* Setup the scan period = strobe + interval */
95 __raw_writel(pdata->strobe,
96 davinci_ks->base + DAVINCI_KEYSCAN_STRBWIDTH);
97 __raw_writel(pdata->interval,
98 davinci_ks->base + DAVINCI_KEYSCAN_INTERVAL);
99 __raw_writel(0x01,
100 davinci_ks->base + DAVINCI_KEYSCAN_CONTTIME);
101
102 /* Define matrix type */
103 switch (pdata->matrix_type) {
104 case DAVINCI_KEYSCAN_MATRIX_4X4:
105 matrix_ctrl = 0;
106 break;
107 case DAVINCI_KEYSCAN_MATRIX_5X3:
108 matrix_ctrl = (1 << 6);
109 break;
110 default:
111 dev_err(dev->parent, "wrong matrix type\n");
112 return -EINVAL;
113 }
114
115 /* Enable key scan module and set matrix type */
116 __raw_writel(DAVINCI_KEYSCAN_AUTODET | DAVINCI_KEYSCAN_KEYEN |
117 matrix_ctrl, davinci_ks->base + DAVINCI_KEYSCAN_KEYCTRL);
118
119 return 0;
120 }
121
davinci_ks_interrupt(int irq,void * dev_id)122 static irqreturn_t davinci_ks_interrupt(int irq, void *dev_id)
123 {
124 struct davinci_ks *davinci_ks = dev_id;
125 struct device *dev = &davinci_ks->input->dev;
126 unsigned short *keymap = davinci_ks->keymap;
127 int keymapsize = davinci_ks->pdata->keymapsize;
128 u32 prev_status, new_status, changed;
129 bool release;
130 int keycode = KEY_UNKNOWN;
131 int i;
132
133 /* Disable interrupt */
134 __raw_writel(0x0, davinci_ks->base + DAVINCI_KEYSCAN_INTENA);
135
136 /* Reading previous and new status of the key scan */
137 prev_status = __raw_readl(davinci_ks->base + DAVINCI_KEYSCAN_PREVSTATE);
138 new_status = __raw_readl(davinci_ks->base + DAVINCI_KEYSCAN_CURRENTST);
139
140 changed = prev_status ^ new_status;
141
142 if (changed) {
143 /*
144 * It goes through all bits in 'changed' to ensure
145 * that no key changes are being missed
146 */
147 for (i = 0 ; i < keymapsize; i++) {
148 if ((changed>>i) & 0x1) {
149 keycode = keymap[i];
150 release = (new_status >> i) & 0x1;
151 dev_dbg(dev->parent, "key %d %s\n", keycode,
152 release ? "released" : "pressed");
153 input_report_key(davinci_ks->input, keycode,
154 !release);
155 input_sync(davinci_ks->input);
156 }
157 }
158 /* Clearing interrupt */
159 __raw_writel(DAVINCI_KEYSCAN_INT_ALL,
160 davinci_ks->base + DAVINCI_KEYSCAN_INTCLR);
161 }
162
163 /* Enable interrupts */
164 __raw_writel(0x1, davinci_ks->base + DAVINCI_KEYSCAN_INTENA);
165
166 return IRQ_HANDLED;
167 }
168
davinci_ks_probe(struct platform_device * pdev)169 static int __init davinci_ks_probe(struct platform_device *pdev)
170 {
171 struct davinci_ks *davinci_ks;
172 struct input_dev *key_dev;
173 struct resource *res, *mem;
174 struct device *dev = &pdev->dev;
175 struct davinci_ks_platform_data *pdata = pdev->dev.platform_data;
176 int error, i;
177
178 if (pdata->device_enable) {
179 error = pdata->device_enable(dev);
180 if (error < 0) {
181 dev_dbg(dev, "device enable function failed\n");
182 return error;
183 }
184 }
185
186 if (!pdata->keymap) {
187 dev_dbg(dev, "no keymap from pdata\n");
188 return -EINVAL;
189 }
190
191 davinci_ks = kzalloc(sizeof(struct davinci_ks) +
192 sizeof(unsigned short) * pdata->keymapsize, GFP_KERNEL);
193 if (!davinci_ks) {
194 dev_dbg(dev, "could not allocate memory for private data\n");
195 return -ENOMEM;
196 }
197
198 memcpy(davinci_ks->keymap, pdata->keymap,
199 sizeof(unsigned short) * pdata->keymapsize);
200
201 key_dev = input_allocate_device();
202 if (!key_dev) {
203 dev_dbg(dev, "could not allocate input device\n");
204 error = -ENOMEM;
205 goto fail1;
206 }
207
208 davinci_ks->input = key_dev;
209
210 davinci_ks->irq = platform_get_irq(pdev, 0);
211 if (davinci_ks->irq < 0) {
212 dev_err(dev, "no key scan irq\n");
213 error = davinci_ks->irq;
214 goto fail2;
215 }
216
217 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
218 if (!res) {
219 dev_err(dev, "no mem resource\n");
220 error = -EINVAL;
221 goto fail2;
222 }
223
224 davinci_ks->pbase = res->start;
225 davinci_ks->base_size = resource_size(res);
226
227 mem = request_mem_region(davinci_ks->pbase, davinci_ks->base_size,
228 pdev->name);
229 if (!mem) {
230 dev_err(dev, "key scan registers at %08x are not free\n",
231 davinci_ks->pbase);
232 error = -EBUSY;
233 goto fail2;
234 }
235
236 davinci_ks->base = ioremap(davinci_ks->pbase, davinci_ks->base_size);
237 if (!davinci_ks->base) {
238 dev_err(dev, "can't ioremap MEM resource.\n");
239 error = -ENOMEM;
240 goto fail3;
241 }
242
243 /* Enable auto repeat feature of Linux input subsystem */
244 if (pdata->rep)
245 __set_bit(EV_REP, key_dev->evbit);
246
247 /* Setup input device */
248 __set_bit(EV_KEY, key_dev->evbit);
249
250 /* Setup the platform data */
251 davinci_ks->pdata = pdata;
252
253 for (i = 0; i < davinci_ks->pdata->keymapsize; i++)
254 __set_bit(davinci_ks->pdata->keymap[i], key_dev->keybit);
255
256 key_dev->name = "davinci_keyscan";
257 key_dev->phys = "davinci_keyscan/input0";
258 key_dev->dev.parent = &pdev->dev;
259 key_dev->id.bustype = BUS_HOST;
260 key_dev->id.vendor = 0x0001;
261 key_dev->id.product = 0x0001;
262 key_dev->id.version = 0x0001;
263 key_dev->keycode = davinci_ks->keymap;
264 key_dev->keycodesize = sizeof(davinci_ks->keymap[0]);
265 key_dev->keycodemax = davinci_ks->pdata->keymapsize;
266
267 error = input_register_device(davinci_ks->input);
268 if (error < 0) {
269 dev_err(dev, "unable to register davinci key scan device\n");
270 goto fail4;
271 }
272
273 error = request_irq(davinci_ks->irq, davinci_ks_interrupt,
274 0, pdev->name, davinci_ks);
275 if (error < 0) {
276 dev_err(dev, "unable to register davinci key scan interrupt\n");
277 goto fail5;
278 }
279
280 error = davinci_ks_initialize(davinci_ks);
281 if (error < 0) {
282 dev_err(dev, "unable to initialize davinci key scan device\n");
283 goto fail6;
284 }
285
286 platform_set_drvdata(pdev, davinci_ks);
287 return 0;
288
289 fail6:
290 free_irq(davinci_ks->irq, davinci_ks);
291 fail5:
292 input_unregister_device(davinci_ks->input);
293 key_dev = NULL;
294 fail4:
295 iounmap(davinci_ks->base);
296 fail3:
297 release_mem_region(davinci_ks->pbase, davinci_ks->base_size);
298 fail2:
299 input_free_device(key_dev);
300 fail1:
301 kfree(davinci_ks);
302
303 return error;
304 }
305
davinci_ks_remove(struct platform_device * pdev)306 static int __devexit davinci_ks_remove(struct platform_device *pdev)
307 {
308 struct davinci_ks *davinci_ks = platform_get_drvdata(pdev);
309
310 free_irq(davinci_ks->irq, davinci_ks);
311
312 input_unregister_device(davinci_ks->input);
313
314 iounmap(davinci_ks->base);
315 release_mem_region(davinci_ks->pbase, davinci_ks->base_size);
316
317 platform_set_drvdata(pdev, NULL);
318
319 kfree(davinci_ks);
320
321 return 0;
322 }
323
324 static struct platform_driver davinci_ks_driver = {
325 .driver = {
326 .name = "davinci_keyscan",
327 .owner = THIS_MODULE,
328 },
329 .remove = __devexit_p(davinci_ks_remove),
330 };
331
davinci_ks_init(void)332 static int __init davinci_ks_init(void)
333 {
334 return platform_driver_probe(&davinci_ks_driver, davinci_ks_probe);
335 }
336 module_init(davinci_ks_init);
337
davinci_ks_exit(void)338 static void __exit davinci_ks_exit(void)
339 {
340 platform_driver_unregister(&davinci_ks_driver);
341 }
342 module_exit(davinci_ks_exit);
343
344 MODULE_AUTHOR("Miguel Aguilar");
345 MODULE_DESCRIPTION("Texas Instruments DaVinci Key Scan Driver");
346 MODULE_LICENSE("GPL");
347