1 /*
2  * SPEAr Keyboard Driver
3  * Based on omap-keypad driver
4  *
5  * Copyright (C) 2010 ST Microelectronics
6  * Rajeev Kumar<rajeev-dlh.kumar@st.com>
7  *
8  * This file is licensed under the terms of the GNU General Public
9  * License version 2. This program is licensed "as is" without any
10  * warranty of any kind, whether express or implied.
11  */
12 
13 #include <linux/clk.h>
14 #include <linux/errno.h>
15 #include <linux/init.h>
16 #include <linux/interrupt.h>
17 #include <linux/input.h>
18 #include <linux/io.h>
19 #include <linux/irq.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_wakeup.h>
24 #include <linux/slab.h>
25 #include <linux/types.h>
26 #include <plat/keyboard.h>
27 
28 /* Keyboard Registers */
29 #define MODE_REG	0x00	/* 16 bit reg */
30 #define STATUS_REG	0x0C	/* 2 bit reg */
31 #define DATA_REG	0x10	/* 8 bit reg */
32 #define INTR_MASK	0x54
33 
34 /* Register Values */
35 /*
36  * pclk freq mask = (APB FEQ -1)= 82 MHZ.Programme bit 15-9 in mode
37  * control register as 1010010(82MHZ)
38  */
39 #define PCLK_FREQ_MSK	0xA400	/* 82 MHz */
40 #define START_SCAN	0x0100
41 #define SCAN_RATE_10	0x0000
42 #define SCAN_RATE_20	0x0004
43 #define SCAN_RATE_40	0x0008
44 #define SCAN_RATE_80	0x000C
45 #define MODE_KEYBOARD	0x0002
46 #define DATA_AVAIL	0x2
47 
48 #define KEY_MASK	0xFF000000
49 #define KEY_VALUE	0x00FFFFFF
50 #define ROW_MASK	0xF0
51 #define COLUMN_MASK	0x0F
52 #define ROW_SHIFT	4
53 
54 struct spear_kbd {
55 	struct input_dev *input;
56 	struct resource *res;
57 	void __iomem *io_base;
58 	struct clk *clk;
59 	unsigned int irq;
60 	unsigned short last_key;
61 	unsigned short keycodes[256];
62 };
63 
64 static irqreturn_t spear_kbd_interrupt(int irq, void *dev_id)
65 {
66 	struct spear_kbd *kbd = dev_id;
67 	struct input_dev *input = kbd->input;
68 	unsigned int key;
69 	u8 sts, val;
70 
71 	sts = readb(kbd->io_base + STATUS_REG);
72 	if (sts & DATA_AVAIL)
73 		return IRQ_NONE;
74 
75 	if (kbd->last_key != KEY_RESERVED) {
76 		input_report_key(input, kbd->last_key, 0);
77 		kbd->last_key = KEY_RESERVED;
78 	}
79 
80 	/* following reads active (row, col) pair */
81 	val = readb(kbd->io_base + DATA_REG);
82 	key = kbd->keycodes[val];
83 
84 	input_event(input, EV_MSC, MSC_SCAN, val);
85 	input_report_key(input, key, 1);
86 	input_sync(input);
87 
88 	kbd->last_key = key;
89 
90 	/* clear interrupt */
91 	writeb(0, kbd->io_base + STATUS_REG);
92 
93 	return IRQ_HANDLED;
94 }
95 
96 static int spear_kbd_open(struct input_dev *dev)
97 {
98 	struct spear_kbd *kbd = input_get_drvdata(dev);
99 	int error;
100 	u16 val;
101 
102 	kbd->last_key = KEY_RESERVED;
103 
104 	error = clk_enable(kbd->clk);
105 	if (error)
106 		return error;
107 
108 	/* program keyboard */
109 	val = SCAN_RATE_80 | MODE_KEYBOARD | PCLK_FREQ_MSK;
110 	writew(val, kbd->io_base + MODE_REG);
111 	writeb(1, kbd->io_base + STATUS_REG);
112 
113 	/* start key scan */
114 	val = readw(kbd->io_base + MODE_REG);
115 	val |= START_SCAN;
116 	writew(val, kbd->io_base + MODE_REG);
117 
118 	return 0;
119 }
120 
121 static void spear_kbd_close(struct input_dev *dev)
122 {
123 	struct spear_kbd *kbd = input_get_drvdata(dev);
124 	u16 val;
125 
126 	/* stop key scan */
127 	val = readw(kbd->io_base + MODE_REG);
128 	val &= ~START_SCAN;
129 	writew(val, kbd->io_base + MODE_REG);
130 
131 	clk_disable(kbd->clk);
132 
133 	kbd->last_key = KEY_RESERVED;
134 }
135 
136 static int __devinit spear_kbd_probe(struct platform_device *pdev)
137 {
138 	const struct kbd_platform_data *pdata = pdev->dev.platform_data;
139 	const struct matrix_keymap_data *keymap;
140 	struct spear_kbd *kbd;
141 	struct input_dev *input_dev;
142 	struct resource *res;
143 	int irq;
144 	int error;
145 
146 	if (!pdata) {
147 		dev_err(&pdev->dev, "Invalid platform data\n");
148 		return -EINVAL;
149 	}
150 
151 	keymap = pdata->keymap;
152 	if (!keymap) {
153 		dev_err(&pdev->dev, "no keymap defined\n");
154 		return -EINVAL;
155 	}
156 
157 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
158 	if (!res) {
159 		dev_err(&pdev->dev, "no keyboard resource defined\n");
160 		return -EBUSY;
161 	}
162 
163 	irq = platform_get_irq(pdev, 0);
164 	if (irq < 0) {
165 		dev_err(&pdev->dev, "not able to get irq for the device\n");
166 		return irq;
167 	}
168 
169 	kbd = kzalloc(sizeof(*kbd), GFP_KERNEL);
170 	input_dev = input_allocate_device();
171 	if (!kbd || !input_dev) {
172 		dev_err(&pdev->dev, "out of memory\n");
173 		error = -ENOMEM;
174 		goto err_free_mem;
175 	}
176 
177 	kbd->input = input_dev;
178 	kbd->irq = irq;
179 	kbd->res = request_mem_region(res->start, resource_size(res),
180 				      pdev->name);
181 	if (!kbd->res) {
182 		dev_err(&pdev->dev, "keyboard region already claimed\n");
183 		error = -EBUSY;
184 		goto err_free_mem;
185 	}
186 
187 	kbd->io_base = ioremap(res->start, resource_size(res));
188 	if (!kbd->io_base) {
189 		dev_err(&pdev->dev, "ioremap failed for kbd_region\n");
190 		error = -ENOMEM;
191 		goto err_release_mem_region;
192 	}
193 
194 	kbd->clk = clk_get(&pdev->dev, NULL);
195 	if (IS_ERR(kbd->clk)) {
196 		error = PTR_ERR(kbd->clk);
197 		goto err_iounmap;
198 	}
199 
200 	input_dev->name = "Spear Keyboard";
201 	input_dev->phys = "keyboard/input0";
202 	input_dev->dev.parent = &pdev->dev;
203 	input_dev->id.bustype = BUS_HOST;
204 	input_dev->id.vendor = 0x0001;
205 	input_dev->id.product = 0x0001;
206 	input_dev->id.version = 0x0100;
207 	input_dev->open = spear_kbd_open;
208 	input_dev->close = spear_kbd_close;
209 
210 	__set_bit(EV_KEY, input_dev->evbit);
211 	if (pdata->rep)
212 		__set_bit(EV_REP, input_dev->evbit);
213 	input_set_capability(input_dev, EV_MSC, MSC_SCAN);
214 
215 	input_dev->keycode = kbd->keycodes;
216 	input_dev->keycodesize = sizeof(kbd->keycodes[0]);
217 	input_dev->keycodemax = ARRAY_SIZE(kbd->keycodes);
218 
219 	matrix_keypad_build_keymap(keymap, ROW_SHIFT,
220 			input_dev->keycode, input_dev->keybit);
221 
222 	input_set_drvdata(input_dev, kbd);
223 
224 	error = request_irq(irq, spear_kbd_interrupt, 0, "keyboard", kbd);
225 	if (error) {
226 		dev_err(&pdev->dev, "request_irq fail\n");
227 		goto err_put_clk;
228 	}
229 
230 	error = input_register_device(input_dev);
231 	if (error) {
232 		dev_err(&pdev->dev, "Unable to register keyboard device\n");
233 		goto err_free_irq;
234 	}
235 
236 	device_init_wakeup(&pdev->dev, 1);
237 	platform_set_drvdata(pdev, kbd);
238 
239 	return 0;
240 
241 err_free_irq:
242 	free_irq(kbd->irq, kbd);
243 err_put_clk:
244 	clk_put(kbd->clk);
245 err_iounmap:
246 	iounmap(kbd->io_base);
247 err_release_mem_region:
248 	release_mem_region(res->start, resource_size(res));
249 err_free_mem:
250 	input_free_device(input_dev);
251 	kfree(kbd);
252 
253 	return error;
254 }
255 
256 static int __devexit spear_kbd_remove(struct platform_device *pdev)
257 {
258 	struct spear_kbd *kbd = platform_get_drvdata(pdev);
259 
260 	free_irq(kbd->irq, kbd);
261 	input_unregister_device(kbd->input);
262 	clk_put(kbd->clk);
263 	iounmap(kbd->io_base);
264 	release_mem_region(kbd->res->start, resource_size(kbd->res));
265 	kfree(kbd);
266 
267 	device_init_wakeup(&pdev->dev, 1);
268 	platform_set_drvdata(pdev, NULL);
269 
270 	return 0;
271 }
272 
273 #ifdef CONFIG_PM
274 static int spear_kbd_suspend(struct device *dev)
275 {
276 	struct platform_device *pdev = to_platform_device(dev);
277 	struct spear_kbd *kbd = platform_get_drvdata(pdev);
278 	struct input_dev *input_dev = kbd->input;
279 
280 	mutex_lock(&input_dev->mutex);
281 
282 	if (input_dev->users)
283 		clk_enable(kbd->clk);
284 
285 	if (device_may_wakeup(&pdev->dev))
286 		enable_irq_wake(kbd->irq);
287 
288 	mutex_unlock(&input_dev->mutex);
289 
290 	return 0;
291 }
292 
293 static int spear_kbd_resume(struct device *dev)
294 {
295 	struct platform_device *pdev = to_platform_device(dev);
296 	struct spear_kbd *kbd = platform_get_drvdata(pdev);
297 	struct input_dev *input_dev = kbd->input;
298 
299 	mutex_lock(&input_dev->mutex);
300 
301 	if (device_may_wakeup(&pdev->dev))
302 		disable_irq_wake(kbd->irq);
303 
304 	if (input_dev->users)
305 		clk_enable(kbd->clk);
306 
307 	mutex_unlock(&input_dev->mutex);
308 
309 	return 0;
310 }
311 
312 static const struct dev_pm_ops spear_kbd_pm_ops = {
313 	.suspend	= spear_kbd_suspend,
314 	.resume		= spear_kbd_resume,
315 };
316 #endif
317 
318 static struct platform_driver spear_kbd_driver = {
319 	.probe		= spear_kbd_probe,
320 	.remove		= __devexit_p(spear_kbd_remove),
321 	.driver		= {
322 		.name	= "keyboard",
323 		.owner	= THIS_MODULE,
324 #ifdef CONFIG_PM
325 		.pm	= &spear_kbd_pm_ops,
326 #endif
327 	},
328 };
329 
330 static int __init spear_kbd_init(void)
331 {
332 	return platform_driver_register(&spear_kbd_driver);
333 }
334 module_init(spear_kbd_init);
335 
336 static void __exit spear_kbd_exit(void)
337 {
338 	platform_driver_unregister(&spear_kbd_driver);
339 }
340 module_exit(spear_kbd_exit);
341 
342 MODULE_AUTHOR("Rajeev Kumar");
343 MODULE_DESCRIPTION("SPEAr Keyboard Driver");
344 MODULE_LICENSE("GPL");
345