2 * DaVinci Key Scan Driver for TI platforms
4 * Copyright (C) 2009 Texas Instruments, Inc
6 * Author: Miguel Aguilar <miguel.aguilar@ridgerun.com>
8 * Intial Code: Sandeep Paulraj <s-paulraj@ti.com>
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.
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.
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
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>
36 #include <mach/hardware.h>
37 #include <mach/irqs.h>
38 #include <mach/keyscan.h>
40 /* Key scan registers */
41 #define DAVINCI_KEYSCAN_KEYCTRL 0x0000
42 #define DAVINCI_KEYSCAN_INTENA 0x0004
43 #define DAVINCI_KEYSCAN_INTFLAG 0x0008
44 #define DAVINCI_KEYSCAN_INTCLR 0x000c
45 #define DAVINCI_KEYSCAN_STRBWIDTH 0x0010
46 #define DAVINCI_KEYSCAN_INTERVAL 0x0014
47 #define DAVINCI_KEYSCAN_CONTTIME 0x0018
48 #define DAVINCI_KEYSCAN_CURRENTST 0x001c
49 #define DAVINCI_KEYSCAN_PREVSTATE 0x0020
50 #define DAVINCI_KEYSCAN_EMUCTRL 0x0024
51 #define DAVINCI_KEYSCAN_IODFTCTRL 0x002c
53 /* Key Control Register (KEYCTRL) */
54 #define DAVINCI_KEYSCAN_KEYEN 0x00000001
55 #define DAVINCI_KEYSCAN_PREVMODE 0x00000002
56 #define DAVINCI_KEYSCAN_CHATOFF 0x00000004
57 #define DAVINCI_KEYSCAN_AUTODET 0x00000008
58 #define DAVINCI_KEYSCAN_SCANMODE 0x00000010
59 #define DAVINCI_KEYSCAN_OUTTYPE 0x00000020
61 /* Masks for the interrupts */
62 #define DAVINCI_KEYSCAN_INT_CONT 0x00000008
63 #define DAVINCI_KEYSCAN_INT_OFF 0x00000004
64 #define DAVINCI_KEYSCAN_INT_ON 0x00000002
65 #define DAVINCI_KEYSCAN_INT_CHANGE 0x00000001
66 #define DAVINCI_KEYSCAN_INT_ALL 0x0000000f
69 struct input_dev *input;
70 struct davinci_ks_platform_data *pdata;
73 resource_size_t pbase;
75 unsigned short keymap[];
78 /* Initializing the kp Module */
79 static int __init davinci_ks_initialize(struct davinci_ks *davinci_ks)
81 struct device *dev = &davinci_ks->input->dev;
82 struct davinci_ks_platform_data *pdata = davinci_ks->pdata;
85 /* Enable all interrupts */
86 __raw_writel(DAVINCI_KEYSCAN_INT_ALL,
87 davinci_ks->base + DAVINCI_KEYSCAN_INTENA);
89 /* Clear interrupts if any */
90 __raw_writel(DAVINCI_KEYSCAN_INT_ALL,
91 davinci_ks->base + DAVINCI_KEYSCAN_INTCLR);
93 /* Setup the scan period = strobe + interval */
94 __raw_writel(pdata->strobe,
95 davinci_ks->base + DAVINCI_KEYSCAN_STRBWIDTH);
96 __raw_writel(pdata->interval,
97 davinci_ks->base + DAVINCI_KEYSCAN_INTERVAL);
99 davinci_ks->base + DAVINCI_KEYSCAN_CONTTIME);
101 /* Define matrix type */
102 switch (pdata->matrix_type) {
103 case DAVINCI_KEYSCAN_MATRIX_4X4:
106 case DAVINCI_KEYSCAN_MATRIX_5X3:
107 matrix_ctrl = (1 << 6);
110 dev_err(dev->parent, "wrong matrix type\n");
114 /* Enable key scan module and set matrix type */
115 __raw_writel(DAVINCI_KEYSCAN_AUTODET | DAVINCI_KEYSCAN_KEYEN |
116 matrix_ctrl, davinci_ks->base + DAVINCI_KEYSCAN_KEYCTRL);
121 static irqreturn_t davinci_ks_interrupt(int irq, void *dev_id)
123 struct davinci_ks *davinci_ks = dev_id;
124 struct device *dev = &davinci_ks->input->dev;
125 unsigned short *keymap = davinci_ks->keymap;
126 int keymapsize = davinci_ks->pdata->keymapsize;
127 u32 prev_status, new_status, changed;
129 int keycode = KEY_UNKNOWN;
132 /* Disable interrupt */
133 __raw_writel(0x0, davinci_ks->base + DAVINCI_KEYSCAN_INTENA);
135 /* Reading previous and new status of the key scan */
136 prev_status = __raw_readl(davinci_ks->base + DAVINCI_KEYSCAN_PREVSTATE);
137 new_status = __raw_readl(davinci_ks->base + DAVINCI_KEYSCAN_CURRENTST);
139 changed = prev_status ^ new_status;
143 * It goes through all bits in 'changed' to ensure
144 * that no key changes are being missed
146 for (i = 0 ; i < keymapsize; i++) {
147 if ((changed>>i) & 0x1) {
149 release = (new_status >> i) & 0x1;
150 dev_dbg(dev->parent, "key %d %s\n", keycode,
151 release ? "released" : "pressed");
152 input_report_key(davinci_ks->input, keycode,
154 input_sync(davinci_ks->input);
157 /* Clearing interrupt */
158 __raw_writel(DAVINCI_KEYSCAN_INT_ALL,
159 davinci_ks->base + DAVINCI_KEYSCAN_INTCLR);
162 /* Enable interrupts */
163 __raw_writel(0x1, davinci_ks->base + DAVINCI_KEYSCAN_INTENA);
168 static int __init davinci_ks_probe(struct platform_device *pdev)
170 struct davinci_ks *davinci_ks;
171 struct input_dev *key_dev;
172 struct resource *res, *mem;
173 struct device *dev = &pdev->dev;
174 struct davinci_ks_platform_data *pdata = pdev->dev.platform_data;
177 if (pdata->device_enable) {
178 error = pdata->device_enable(dev);
180 dev_dbg(dev, "device enable function failed\n");
185 if (!pdata->keymap) {
186 dev_dbg(dev, "no keymap from pdata\n");
190 davinci_ks = kzalloc(sizeof(struct davinci_ks) +
191 sizeof(unsigned short) * pdata->keymapsize, GFP_KERNEL);
193 dev_dbg(dev, "could not allocate memory for private data\n");
197 memcpy(davinci_ks->keymap, pdata->keymap,
198 sizeof(unsigned short) * pdata->keymapsize);
200 key_dev = input_allocate_device();
202 dev_dbg(dev, "could not allocate input device\n");
207 davinci_ks->input = key_dev;
209 davinci_ks->irq = platform_get_irq(pdev, 0);
210 if (davinci_ks->irq < 0) {
211 dev_err(dev, "no key scan irq\n");
212 error = davinci_ks->irq;
216 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
218 dev_err(dev, "no mem resource\n");
223 davinci_ks->pbase = res->start;
224 davinci_ks->base_size = resource_size(res);
226 mem = request_mem_region(davinci_ks->pbase, davinci_ks->base_size,
229 dev_err(dev, "key scan registers at %08x are not free\n",
235 davinci_ks->base = ioremap(davinci_ks->pbase, davinci_ks->base_size);
236 if (!davinci_ks->base) {
237 dev_err(dev, "can't ioremap MEM resource.\n");
242 /* Enable auto repeat feature of Linux input subsystem */
244 __set_bit(EV_REP, key_dev->evbit);
246 /* Setup input device */
247 __set_bit(EV_KEY, key_dev->evbit);
249 /* Setup the platform data */
250 davinci_ks->pdata = pdata;
252 for (i = 0; i < davinci_ks->pdata->keymapsize; i++)
253 __set_bit(davinci_ks->pdata->keymap[i], key_dev->keybit);
255 key_dev->name = "davinci_keyscan";
256 key_dev->phys = "davinci_keyscan/input0";
257 key_dev->dev.parent = &pdev->dev;
258 key_dev->id.bustype = BUS_HOST;
259 key_dev->id.vendor = 0x0001;
260 key_dev->id.product = 0x0001;
261 key_dev->id.version = 0x0001;
262 key_dev->keycode = davinci_ks->keymap;
263 key_dev->keycodesize = sizeof(davinci_ks->keymap[0]);
264 key_dev->keycodemax = davinci_ks->pdata->keymapsize;
266 error = input_register_device(davinci_ks->input);
268 dev_err(dev, "unable to register davinci key scan device\n");
272 error = request_irq(davinci_ks->irq, davinci_ks_interrupt,
273 IRQF_DISABLED, pdev->name, davinci_ks);
275 dev_err(dev, "unable to register davinci key scan interrupt\n");
279 error = davinci_ks_initialize(davinci_ks);
281 dev_err(dev, "unable to initialize davinci key scan device\n");
285 platform_set_drvdata(pdev, davinci_ks);
289 free_irq(davinci_ks->irq, davinci_ks);
291 input_unregister_device(davinci_ks->input);
294 iounmap(davinci_ks->base);
296 release_mem_region(davinci_ks->pbase, davinci_ks->base_size);
298 input_free_device(key_dev);
305 static int __devexit davinci_ks_remove(struct platform_device *pdev)
307 struct davinci_ks *davinci_ks = platform_get_drvdata(pdev);
309 free_irq(davinci_ks->irq, davinci_ks);
311 input_unregister_device(davinci_ks->input);
313 iounmap(davinci_ks->base);
314 release_mem_region(davinci_ks->pbase, davinci_ks->base_size);
316 platform_set_drvdata(pdev, NULL);
323 static struct platform_driver davinci_ks_driver = {
325 .name = "davinci_keyscan",
326 .owner = THIS_MODULE,
328 .remove = __devexit_p(davinci_ks_remove),
331 static int __init davinci_ks_init(void)
333 return platform_driver_probe(&davinci_ks_driver, davinci_ks_probe);
335 module_init(davinci_ks_init);
337 static void __exit davinci_ks_exit(void)
339 platform_driver_unregister(&davinci_ks_driver);
341 module_exit(davinci_ks_exit);
343 MODULE_AUTHOR("Miguel Aguilar");
344 MODULE_DESCRIPTION("Texas Instruments DaVinci Key Scan Driver");
345 MODULE_LICENSE("GPL");