7c19d9b2278502f4d8ec5d875a602a5357bb2ece
[sfrench/cifs-2.6.git] / drivers / char / tb0219.c
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
96 static inline char get_led(void)
97 {
98         return (char)tb0219_read(TB0219_LED);
99 }
100
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
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
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
134 static inline int set_led(char command)
135 {
136         tb0219_write(TB0219_LED, command);
137
138         return 0;
139 }
140
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
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
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
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
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
268 static void tb0219_restart(char *command)
269 {
270         tb0219_write(TB0219_RESET, 0);
271 }
272
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
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
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
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
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);