1 /*
2  *  Driver for TANBAC TB0219 base board.
3  *
4  *  Copyright (C) 2005  Yoichi Yuasa <yuasa@linux-mips.org>
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation; either version 2 of the License, or
9  *  (at your option) any later version.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with this program; if not, write to the Free Software
18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  */
20 #include <linux/platform_device.h>
21 #include <linux/fs.h>
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/uaccess.h>
25 
26 #include <asm/io.h>
27 #include <asm/reboot.h>
28 #include <asm/vr41xx/giu.h>
29 #include <asm/vr41xx/tb0219.h>
30 
31 MODULE_AUTHOR("Yoichi Yuasa <yuasa@linux-mips.org>");
32 MODULE_DESCRIPTION("TANBAC TB0219 base board driver");
33 MODULE_LICENSE("GPL");
34 
35 static int major;	/* default is dynamic major device number */
36 module_param(major, int, 0);
37 MODULE_PARM_DESC(major, "Major device number");
38 
39 static void (*old_machine_restart)(char *command);
40 static void __iomem *tb0219_base;
41 static DEFINE_SPINLOCK(tb0219_lock);
42 
43 #define tb0219_read(offset)		readw(tb0219_base + (offset))
44 #define tb0219_write(offset, value)	writew((value), tb0219_base + (offset))
45 
46 #define TB0219_START	0x0a000000UL
47 #define TB0219_SIZE	0x20UL
48 
49 #define TB0219_LED			0x00
50 #define TB0219_GPIO_INPUT		0x02
51 #define TB0219_GPIO_OUTPUT		0x04
52 #define TB0219_DIP_SWITCH		0x06
53 #define TB0219_MISC			0x08
54 #define TB0219_RESET			0x0e
55 #define TB0219_PCI_SLOT1_IRQ_STATUS	0x10
56 #define TB0219_PCI_SLOT2_IRQ_STATUS	0x12
57 #define TB0219_PCI_SLOT3_IRQ_STATUS	0x14
58 
59 typedef enum {
60 	TYPE_LED,
61 	TYPE_GPIO_OUTPUT,
62 } tb0219_type_t;
63 
64 /*
65  * Minor device number
66  *	 0 = 7 segment LED
67  *
68  *	16 = GPIO IN 0
69  *	17 = GPIO IN 1
70  *	18 = GPIO IN 2
71  *	19 = GPIO IN 3
72  *	20 = GPIO IN 4
73  *	21 = GPIO IN 5
74  *	22 = GPIO IN 6
75  *	23 = GPIO IN 7
76  *
77  *	32 = GPIO OUT 0
78  *	33 = GPIO OUT 1
79  *	34 = GPIO OUT 2
80  *	35 = GPIO OUT 3
81  *	36 = GPIO OUT 4
82  *	37 = GPIO OUT 5
83  *	38 = GPIO OUT 6
84  *	39 = GPIO OUT 7
85  *
86  *	48 = DIP switch 1
87  *	49 = DIP switch 2
88  *	50 = DIP switch 3
89  *	51 = DIP switch 4
90  *	52 = DIP switch 5
91  *	53 = DIP switch 6
92  *	54 = DIP switch 7
93  *	55 = DIP switch 8
94  */
95 
get_led(void)96 static inline char get_led(void)
97 {
98 	return (char)tb0219_read(TB0219_LED);
99 }
100 
get_gpio_input_pin(unsigned int pin)101 static inline char get_gpio_input_pin(unsigned int pin)
102 {
103 	uint16_t values;
104 
105 	values = tb0219_read(TB0219_GPIO_INPUT);
106 	if (values & (1 << pin))
107 		return '1';
108 
109 	return '0';
110 }
111 
get_gpio_output_pin(unsigned int pin)112 static inline char get_gpio_output_pin(unsigned int pin)
113 {
114 	uint16_t values;
115 
116 	values = tb0219_read(TB0219_GPIO_OUTPUT);
117 	if (values & (1 << pin))
118 		return '1';
119 
120 	return '0';
121 }
122 
get_dip_switch(unsigned int pin)123 static inline char get_dip_switch(unsigned int pin)
124 {
125 	uint16_t values;
126 
127 	values = tb0219_read(TB0219_DIP_SWITCH);
128 	if (values & (1 << pin))
129 		return '1';
130 
131 	return '0';
132 }
133 
set_led(char command)134 static inline int set_led(char command)
135 {
136 	tb0219_write(TB0219_LED, command);
137 
138 	return 0;
139 }
140 
set_gpio_output_pin(unsigned int pin,char command)141 static inline int set_gpio_output_pin(unsigned int pin, char command)
142 {
143 	unsigned long flags;
144 	uint16_t value;
145 
146 	if (command != '0' && command != '1')
147 		return -EINVAL;
148 
149 	spin_lock_irqsave(&tb0219_lock, flags);
150 	value = tb0219_read(TB0219_GPIO_OUTPUT);
151 	if (command == '0')
152 		value &= ~(1 << pin);
153 	else
154 		value |= 1 << pin;
155 	tb0219_write(TB0219_GPIO_OUTPUT, value);
156 	spin_unlock_irqrestore(&tb0219_lock, flags);
157 
158 	return 0;
159 
160 }
161 
tanbac_tb0219_read(struct file * file,char __user * buf,size_t len,loff_t * ppos)162 static ssize_t tanbac_tb0219_read(struct file *file, char __user *buf, size_t len,
163                                   loff_t *ppos)
164 {
165 	unsigned int minor;
166 	char value;
167 
168 	minor = iminor(file_inode(file));
169 	switch (minor) {
170 	case 0:
171 		value = get_led();
172 		break;
173 	case 16 ... 23:
174 		value = get_gpio_input_pin(minor - 16);
175 		break;
176 	case 32 ... 39:
177 		value = get_gpio_output_pin(minor - 32);
178 		break;
179 	case 48 ... 55:
180 		value = get_dip_switch(minor - 48);
181 		break;
182 	default:
183 		return -EBADF;
184 	}
185 
186 	if (len <= 0)
187 		return -EFAULT;
188 
189 	if (put_user(value, buf))
190 		return -EFAULT;
191 
192 	return 1;
193 }
194 
tanbac_tb0219_write(struct file * file,const char __user * data,size_t len,loff_t * ppos)195 static ssize_t tanbac_tb0219_write(struct file *file, const char __user *data,
196                                    size_t len, loff_t *ppos)
197 {
198 	unsigned int minor;
199 	tb0219_type_t type;
200 	size_t i;
201 	int retval = 0;
202 	char c;
203 
204 	minor = iminor(file_inode(file));
205 	switch (minor) {
206 	case 0:
207 		type = TYPE_LED;
208 		break;
209 	case 32 ... 39:
210 		type = TYPE_GPIO_OUTPUT;
211 		break;
212 	default:
213 		return -EBADF;
214 	}
215 
216 	for (i = 0; i < len; i++) {
217 		if (get_user(c, data + i))
218 			return -EFAULT;
219 
220 		switch (type) {
221 		case TYPE_LED:
222 			retval = set_led(c);
223 			break;
224 		case TYPE_GPIO_OUTPUT:
225 			retval = set_gpio_output_pin(minor - 32, c);
226 			break;
227 		}
228 
229 		if (retval < 0)
230 			break;
231 	}
232 
233 	return i;
234 }
235 
tanbac_tb0219_open(struct inode * inode,struct file * file)236 static int tanbac_tb0219_open(struct inode *inode, struct file *file)
237 {
238 	unsigned int minor;
239 
240 	minor = iminor(inode);
241 	switch (minor) {
242 	case 0:
243 	case 16 ... 23:
244 	case 32 ... 39:
245 	case 48 ... 55:
246 		return nonseekable_open(inode, file);
247 	default:
248 		break;
249 	}
250 
251 	return -EBADF;
252 }
253 
tanbac_tb0219_release(struct inode * inode,struct file * file)254 static int tanbac_tb0219_release(struct inode *inode, struct file *file)
255 {
256 	return 0;
257 }
258 
259 static const struct file_operations tb0219_fops = {
260 	.owner		= THIS_MODULE,
261 	.read		= tanbac_tb0219_read,
262 	.write		= tanbac_tb0219_write,
263 	.open		= tanbac_tb0219_open,
264 	.release	= tanbac_tb0219_release,
265 	.llseek		= no_llseek,
266 };
267 
tb0219_restart(char * command)268 static void tb0219_restart(char *command)
269 {
270 	tb0219_write(TB0219_RESET, 0);
271 }
272 
tb0219_pci_irq_init(void)273 static void tb0219_pci_irq_init(void)
274 {
275 	/* PCI Slot 1 */
276 	vr41xx_set_irq_trigger(TB0219_PCI_SLOT1_PIN, IRQ_TRIGGER_LEVEL, IRQ_SIGNAL_THROUGH);
277 	vr41xx_set_irq_level(TB0219_PCI_SLOT1_PIN, IRQ_LEVEL_LOW);
278 
279 	/* PCI Slot 2 */
280 	vr41xx_set_irq_trigger(TB0219_PCI_SLOT2_PIN, IRQ_TRIGGER_LEVEL, IRQ_SIGNAL_THROUGH);
281 	vr41xx_set_irq_level(TB0219_PCI_SLOT2_PIN, IRQ_LEVEL_LOW);
282 
283 	/* PCI Slot 3 */
284 	vr41xx_set_irq_trigger(TB0219_PCI_SLOT3_PIN, IRQ_TRIGGER_LEVEL, IRQ_SIGNAL_THROUGH);
285 	vr41xx_set_irq_level(TB0219_PCI_SLOT3_PIN, IRQ_LEVEL_LOW);
286 }
287 
tb0219_probe(struct platform_device * dev)288 static int tb0219_probe(struct platform_device *dev)
289 {
290 	int retval;
291 
292 	if (request_mem_region(TB0219_START, TB0219_SIZE, "TB0219") == NULL)
293 		return -EBUSY;
294 
295 	tb0219_base = ioremap(TB0219_START, TB0219_SIZE);
296 	if (tb0219_base == NULL) {
297 		release_mem_region(TB0219_START, TB0219_SIZE);
298 		return -ENOMEM;
299 	}
300 
301 	retval = register_chrdev(major, "TB0219", &tb0219_fops);
302 	if (retval < 0) {
303 		iounmap(tb0219_base);
304 		tb0219_base = NULL;
305 		release_mem_region(TB0219_START, TB0219_SIZE);
306 		return retval;
307 	}
308 
309 	old_machine_restart = _machine_restart;
310 	_machine_restart = tb0219_restart;
311 
312 	tb0219_pci_irq_init();
313 
314 	if (major == 0) {
315 		major = retval;
316 		printk(KERN_INFO "TB0219: major number %d\n", major);
317 	}
318 
319 	return 0;
320 }
321 
tb0219_remove(struct platform_device * dev)322 static int tb0219_remove(struct platform_device *dev)
323 {
324 	_machine_restart = old_machine_restart;
325 
326 	iounmap(tb0219_base);
327 	tb0219_base = NULL;
328 
329 	release_mem_region(TB0219_START, TB0219_SIZE);
330 
331 	return 0;
332 }
333 
334 static struct platform_device *tb0219_platform_device;
335 
336 static struct platform_driver tb0219_device_driver = {
337 	.probe		= tb0219_probe,
338 	.remove		= tb0219_remove,
339 	.driver		= {
340 		.name	= "TB0219",
341 	},
342 };
343 
tanbac_tb0219_init(void)344 static int __init tanbac_tb0219_init(void)
345 {
346 	int retval;
347 
348 	tb0219_platform_device = platform_device_alloc("TB0219", -1);
349 	if (!tb0219_platform_device)
350 		return -ENOMEM;
351 
352 	retval = platform_device_add(tb0219_platform_device);
353 	if (retval < 0) {
354 		platform_device_put(tb0219_platform_device);
355 		return retval;
356 	}
357 
358 	retval = platform_driver_register(&tb0219_device_driver);
359 	if (retval < 0)
360 		platform_device_unregister(tb0219_platform_device);
361 
362 	return retval;
363 }
364 
tanbac_tb0219_exit(void)365 static void __exit tanbac_tb0219_exit(void)
366 {
367 	platform_driver_unregister(&tb0219_device_driver);
368 	platform_device_unregister(tb0219_platform_device);
369 }
370 
371 module_init(tanbac_tb0219_init);
372 module_exit(tanbac_tb0219_exit);
373