1 /*
2 * arch/arm/mach-ks8695/gpio.c
3 *
4 * Copyright (C) 2006 Andrew Victor
5 * Updated to GPIOLIB, Copyright 2008 Simtec Electronics
6 * Daniel Silverstone <dsilvers@simtec.co.uk>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 */
21
22 #include <linux/kernel.h>
23 #include <linux/mm.h>
24 #include <linux/init.h>
25 #include <linux/debugfs.h>
26 #include <linux/seq_file.h>
27 #include <linux/module.h>
28 #include <linux/io.h>
29
30 #include <mach/hardware.h>
31 #include <asm/mach/irq.h>
32
33 #include <mach/regs-gpio.h>
34 #include <mach/gpio.h>
35
36 /*
37 * Configure a GPIO line for either GPIO function, or its internal
38 * function (Interrupt, Timer, etc).
39 */
ks8695_gpio_mode(unsigned int pin,short gpio)40 static void ks8695_gpio_mode(unsigned int pin, short gpio)
41 {
42 unsigned int enable[] = { IOPC_IOEINT0EN, IOPC_IOEINT1EN, IOPC_IOEINT2EN, IOPC_IOEINT3EN, IOPC_IOTIM0EN, IOPC_IOTIM1EN };
43 unsigned long x, flags;
44
45 if (pin > KS8695_GPIO_5) /* only GPIO 0..5 have internal functions */
46 return;
47
48 local_irq_save(flags);
49
50 x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPC);
51 if (gpio) /* GPIO: set bit to 0 */
52 x &= ~enable[pin];
53 else /* Internal function: set bit to 1 */
54 x |= enable[pin];
55 __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPC);
56
57 local_irq_restore(flags);
58 }
59
60
61 static unsigned short gpio_irq[] = { KS8695_IRQ_EXTERN0, KS8695_IRQ_EXTERN1, KS8695_IRQ_EXTERN2, KS8695_IRQ_EXTERN3 };
62
63 /*
64 * Configure GPIO pin as external interrupt source.
65 */
ks8695_gpio_interrupt(unsigned int pin,unsigned int type)66 int ks8695_gpio_interrupt(unsigned int pin, unsigned int type)
67 {
68 unsigned long x, flags;
69
70 if (pin > KS8695_GPIO_3) /* only GPIO 0..3 can generate IRQ */
71 return -EINVAL;
72
73 local_irq_save(flags);
74
75 /* set pin as input */
76 x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
77 x &= ~IOPM(pin);
78 __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM);
79
80 local_irq_restore(flags);
81
82 /* Set IRQ triggering type */
83 set_irq_type(gpio_irq[pin], type);
84
85 /* enable interrupt mode */
86 ks8695_gpio_mode(pin, 0);
87
88 return 0;
89 }
90 EXPORT_SYMBOL(ks8695_gpio_interrupt);
91
92
93
94 /* .... Generic GPIO interface .............................................. */
95
96 /*
97 * Configure the GPIO line as an input.
98 */
ks8695_gpio_direction_input(struct gpio_chip * gc,unsigned int pin)99 static int ks8695_gpio_direction_input(struct gpio_chip *gc, unsigned int pin)
100 {
101 unsigned long x, flags;
102
103 if (pin > KS8695_GPIO_15)
104 return -EINVAL;
105
106 /* set pin to GPIO mode */
107 ks8695_gpio_mode(pin, 1);
108
109 local_irq_save(flags);
110
111 /* set pin as input */
112 x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
113 x &= ~IOPM(pin);
114 __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM);
115
116 local_irq_restore(flags);
117
118 return 0;
119 }
120
121
122 /*
123 * Configure the GPIO line as an output, with default state.
124 */
ks8695_gpio_direction_output(struct gpio_chip * gc,unsigned int pin,int state)125 static int ks8695_gpio_direction_output(struct gpio_chip *gc,
126 unsigned int pin, int state)
127 {
128 unsigned long x, flags;
129
130 if (pin > KS8695_GPIO_15)
131 return -EINVAL;
132
133 /* set pin to GPIO mode */
134 ks8695_gpio_mode(pin, 1);
135
136 local_irq_save(flags);
137
138 /* set line state */
139 x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
140 if (state)
141 x |= IOPD(pin);
142 else
143 x &= ~IOPD(pin);
144 __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPD);
145
146 /* set pin as output */
147 x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
148 x |= IOPM(pin);
149 __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPM);
150
151 local_irq_restore(flags);
152
153 return 0;
154 }
155
156
157 /*
158 * Set the state of an output GPIO line.
159 */
ks8695_gpio_set_value(struct gpio_chip * gc,unsigned int pin,int state)160 static void ks8695_gpio_set_value(struct gpio_chip *gc,
161 unsigned int pin, int state)
162 {
163 unsigned long x, flags;
164
165 if (pin > KS8695_GPIO_15)
166 return;
167
168 local_irq_save(flags);
169
170 /* set output line state */
171 x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
172 if (state)
173 x |= IOPD(pin);
174 else
175 x &= ~IOPD(pin);
176 __raw_writel(x, KS8695_GPIO_VA + KS8695_IOPD);
177
178 local_irq_restore(flags);
179 }
180
181
182 /*
183 * Read the state of a GPIO line.
184 */
ks8695_gpio_get_value(struct gpio_chip * gc,unsigned int pin)185 static int ks8695_gpio_get_value(struct gpio_chip *gc, unsigned int pin)
186 {
187 unsigned long x;
188
189 if (pin > KS8695_GPIO_15)
190 return -EINVAL;
191
192 x = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
193 return (x & IOPD(pin)) != 0;
194 }
195
196
197 /*
198 * Map GPIO line to IRQ number.
199 */
ks8695_gpio_to_irq(struct gpio_chip * gc,unsigned int pin)200 static int ks8695_gpio_to_irq(struct gpio_chip *gc, unsigned int pin)
201 {
202 if (pin > KS8695_GPIO_3) /* only GPIO 0..3 can generate IRQ */
203 return -EINVAL;
204
205 return gpio_irq[pin];
206 }
207
208 /*
209 * Map IRQ number to GPIO line.
210 */
irq_to_gpio(unsigned int irq)211 int irq_to_gpio(unsigned int irq)
212 {
213 if ((irq < KS8695_IRQ_EXTERN0) || (irq > KS8695_IRQ_EXTERN3))
214 return -EINVAL;
215
216 return (irq - KS8695_IRQ_EXTERN0);
217 }
218 EXPORT_SYMBOL(irq_to_gpio);
219
220 /* GPIOLIB interface */
221
222 static struct gpio_chip ks8695_gpio_chip = {
223 .label = "KS8695",
224 .direction_input = ks8695_gpio_direction_input,
225 .direction_output = ks8695_gpio_direction_output,
226 .get = ks8695_gpio_get_value,
227 .set = ks8695_gpio_set_value,
228 .to_irq = ks8695_gpio_to_irq,
229 .base = 0,
230 .ngpio = 16,
231 .can_sleep = 0,
232 };
233
234 /* Register the GPIOs */
ks8695_register_gpios(void)235 void ks8695_register_gpios(void)
236 {
237 if (gpiochip_add(&ks8695_gpio_chip))
238 printk(KERN_ERR "Unable to register core GPIOs\n");
239 }
240
241 /* .... Debug interface ..................................................... */
242
243 #ifdef CONFIG_DEBUG_FS
244
ks8695_gpio_show(struct seq_file * s,void * unused)245 static int ks8695_gpio_show(struct seq_file *s, void *unused)
246 {
247 unsigned int enable[] = { IOPC_IOEINT0EN, IOPC_IOEINT1EN, IOPC_IOEINT2EN, IOPC_IOEINT3EN, IOPC_IOTIM0EN, IOPC_IOTIM1EN };
248 unsigned int intmask[] = { IOPC_IOEINT0TM, IOPC_IOEINT1TM, IOPC_IOEINT2TM, IOPC_IOEINT3TM };
249 unsigned long mode, ctrl, data;
250 int i;
251
252 mode = __raw_readl(KS8695_GPIO_VA + KS8695_IOPM);
253 ctrl = __raw_readl(KS8695_GPIO_VA + KS8695_IOPC);
254 data = __raw_readl(KS8695_GPIO_VA + KS8695_IOPD);
255
256 seq_printf(s, "Pin\tI/O\tFunction\tState\n\n");
257
258 for (i = KS8695_GPIO_0; i <= KS8695_GPIO_15 ; i++) {
259 seq_printf(s, "%i:\t", i);
260
261 seq_printf(s, "%s\t", (mode & IOPM(i)) ? "Output" : "Input");
262
263 if (i <= KS8695_GPIO_3) {
264 if (ctrl & enable[i]) {
265 seq_printf(s, "EXT%i ", i);
266
267 switch ((ctrl & intmask[i]) >> (4 * i)) {
268 case IOPC_TM_LOW:
269 seq_printf(s, "(Low)"); break;
270 case IOPC_TM_HIGH:
271 seq_printf(s, "(High)"); break;
272 case IOPC_TM_RISING:
273 seq_printf(s, "(Rising)"); break;
274 case IOPC_TM_FALLING:
275 seq_printf(s, "(Falling)"); break;
276 case IOPC_TM_EDGE:
277 seq_printf(s, "(Edges)"); break;
278 }
279 }
280 else
281 seq_printf(s, "GPIO\t");
282 }
283 else if (i <= KS8695_GPIO_5) {
284 if (ctrl & enable[i])
285 seq_printf(s, "TOUT%i\t", i - KS8695_GPIO_4);
286 else
287 seq_printf(s, "GPIO\t");
288 }
289 else
290 seq_printf(s, "GPIO\t");
291
292 seq_printf(s, "\t");
293
294 seq_printf(s, "%i\n", (data & IOPD(i)) ? 1 : 0);
295 }
296 return 0;
297 }
298
ks8695_gpio_open(struct inode * inode,struct file * file)299 static int ks8695_gpio_open(struct inode *inode, struct file *file)
300 {
301 return single_open(file, ks8695_gpio_show, NULL);
302 }
303
304 static const struct file_operations ks8695_gpio_operations = {
305 .open = ks8695_gpio_open,
306 .read = seq_read,
307 .llseek = seq_lseek,
308 .release = single_release,
309 };
310
ks8695_gpio_debugfs_init(void)311 static int __init ks8695_gpio_debugfs_init(void)
312 {
313 /* /sys/kernel/debug/ks8695_gpio */
314 (void) debugfs_create_file("ks8695_gpio", S_IFREG | S_IRUGO, NULL, NULL, &ks8695_gpio_operations);
315 return 0;
316 }
317 postcore_initcall(ks8695_gpio_debugfs_init);
318
319 #endif
320