1 /*
2 * arch/arm/mach-tegra/gpio.c
3 *
4 * Copyright (c) 2010 Google, Inc
5 *
6 * Author:
7 * Erik Gilling <konkers@google.com>
8 *
9 * This software is licensed under the terms of the GNU General Public
10 * License version 2, as published by the Free Software Foundation, and
11 * may be copied, distributed, and modified under those terms.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 */
19
20 #include <linux/init.h>
21 #include <linux/irq.h>
22 #include <linux/interrupt.h>
23
24 #include <linux/io.h>
25 #include <linux/gpio.h>
26
27 #include <mach/iomap.h>
28 #include <mach/suspend.h>
29
30 #define GPIO_BANK(x) ((x) >> 5)
31 #define GPIO_PORT(x) (((x) >> 3) & 0x3)
32 #define GPIO_BIT(x) ((x) & 0x7)
33
34 #define GPIO_REG(x) (IO_TO_VIRT(TEGRA_GPIO_BASE) + \
35 GPIO_BANK(x) * 0x80 + \
36 GPIO_PORT(x) * 4)
37
38 #define GPIO_CNF(x) (GPIO_REG(x) + 0x00)
39 #define GPIO_OE(x) (GPIO_REG(x) + 0x10)
40 #define GPIO_OUT(x) (GPIO_REG(x) + 0X20)
41 #define GPIO_IN(x) (GPIO_REG(x) + 0x30)
42 #define GPIO_INT_STA(x) (GPIO_REG(x) + 0x40)
43 #define GPIO_INT_ENB(x) (GPIO_REG(x) + 0x50)
44 #define GPIO_INT_LVL(x) (GPIO_REG(x) + 0x60)
45 #define GPIO_INT_CLR(x) (GPIO_REG(x) + 0x70)
46
47 #define GPIO_MSK_CNF(x) (GPIO_REG(x) + 0x800)
48 #define GPIO_MSK_OE(x) (GPIO_REG(x) + 0x810)
49 #define GPIO_MSK_OUT(x) (GPIO_REG(x) + 0X820)
50 #define GPIO_MSK_INT_STA(x) (GPIO_REG(x) + 0x840)
51 #define GPIO_MSK_INT_ENB(x) (GPIO_REG(x) + 0x850)
52 #define GPIO_MSK_INT_LVL(x) (GPIO_REG(x) + 0x860)
53
54 #define GPIO_INT_LVL_MASK 0x010101
55 #define GPIO_INT_LVL_EDGE_RISING 0x000101
56 #define GPIO_INT_LVL_EDGE_FALLING 0x000100
57 #define GPIO_INT_LVL_EDGE_BOTH 0x010100
58 #define GPIO_INT_LVL_LEVEL_HIGH 0x000001
59 #define GPIO_INT_LVL_LEVEL_LOW 0x000000
60
61 struct tegra_gpio_bank {
62 int bank;
63 int irq;
64 spinlock_t lvl_lock[4];
65 #ifdef CONFIG_PM
66 u32 cnf[4];
67 u32 out[4];
68 u32 oe[4];
69 u32 int_enb[4];
70 u32 int_lvl[4];
71 #endif
72 };
73
74
75 static struct tegra_gpio_bank tegra_gpio_banks[] = {
76 {.bank = 0, .irq = INT_GPIO1},
77 {.bank = 1, .irq = INT_GPIO2},
78 {.bank = 2, .irq = INT_GPIO3},
79 {.bank = 3, .irq = INT_GPIO4},
80 {.bank = 4, .irq = INT_GPIO5},
81 {.bank = 5, .irq = INT_GPIO6},
82 {.bank = 6, .irq = INT_GPIO7},
83 };
84
tegra_gpio_compose(int bank,int port,int bit)85 static int tegra_gpio_compose(int bank, int port, int bit)
86 {
87 return (bank << 5) | ((port & 0x3) << 3) | (bit & 0x7);
88 }
89
tegra_gpio_mask_write(u32 reg,int gpio,int value)90 static void tegra_gpio_mask_write(u32 reg, int gpio, int value)
91 {
92 u32 val;
93
94 val = 0x100 << GPIO_BIT(gpio);
95 if (value)
96 val |= 1 << GPIO_BIT(gpio);
97 __raw_writel(val, reg);
98 }
99
tegra_gpio_enable(int gpio)100 void tegra_gpio_enable(int gpio)
101 {
102 tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 1);
103 }
104
tegra_gpio_disable(int gpio)105 void tegra_gpio_disable(int gpio)
106 {
107 tegra_gpio_mask_write(GPIO_MSK_CNF(gpio), gpio, 0);
108 }
109
tegra_gpio_set(struct gpio_chip * chip,unsigned offset,int value)110 static void tegra_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
111 {
112 tegra_gpio_mask_write(GPIO_MSK_OUT(offset), offset, value);
113 }
114
tegra_gpio_get(struct gpio_chip * chip,unsigned offset)115 static int tegra_gpio_get(struct gpio_chip *chip, unsigned offset)
116 {
117 return (__raw_readl(GPIO_IN(offset)) >> GPIO_BIT(offset)) & 0x1;
118 }
119
tegra_gpio_direction_input(struct gpio_chip * chip,unsigned offset)120 static int tegra_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
121 {
122 tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 0);
123 return 0;
124 }
125
tegra_gpio_direction_output(struct gpio_chip * chip,unsigned offset,int value)126 static int tegra_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
127 int value)
128 {
129 tegra_gpio_set(chip, offset, value);
130 tegra_gpio_mask_write(GPIO_MSK_OE(offset), offset, 1);
131 return 0;
132 }
133
134
135
136 static struct gpio_chip tegra_gpio_chip = {
137 .label = "tegra-gpio",
138 .direction_input = tegra_gpio_direction_input,
139 .get = tegra_gpio_get,
140 .direction_output = tegra_gpio_direction_output,
141 .set = tegra_gpio_set,
142 .base = 0,
143 .ngpio = TEGRA_NR_GPIOS,
144 };
145
tegra_gpio_irq_ack(struct irq_data * d)146 static void tegra_gpio_irq_ack(struct irq_data *d)
147 {
148 int gpio = d->irq - INT_GPIO_BASE;
149
150 __raw_writel(1 << GPIO_BIT(gpio), GPIO_INT_CLR(gpio));
151 }
152
tegra_gpio_irq_mask(struct irq_data * d)153 static void tegra_gpio_irq_mask(struct irq_data *d)
154 {
155 int gpio = d->irq - INT_GPIO_BASE;
156
157 tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 0);
158 }
159
tegra_gpio_irq_unmask(struct irq_data * d)160 static void tegra_gpio_irq_unmask(struct irq_data *d)
161 {
162 int gpio = d->irq - INT_GPIO_BASE;
163
164 tegra_gpio_mask_write(GPIO_MSK_INT_ENB(gpio), gpio, 1);
165 }
166
tegra_gpio_irq_set_type(struct irq_data * d,unsigned int type)167 static int tegra_gpio_irq_set_type(struct irq_data *d, unsigned int type)
168 {
169 int gpio = d->irq - INT_GPIO_BASE;
170 struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d);
171 int port = GPIO_PORT(gpio);
172 int lvl_type;
173 int val;
174 unsigned long flags;
175
176 switch (type & IRQ_TYPE_SENSE_MASK) {
177 case IRQ_TYPE_EDGE_RISING:
178 lvl_type = GPIO_INT_LVL_EDGE_RISING;
179 break;
180
181 case IRQ_TYPE_EDGE_FALLING:
182 lvl_type = GPIO_INT_LVL_EDGE_FALLING;
183 break;
184
185 case IRQ_TYPE_EDGE_BOTH:
186 lvl_type = GPIO_INT_LVL_EDGE_BOTH;
187 break;
188
189 case IRQ_TYPE_LEVEL_HIGH:
190 lvl_type = GPIO_INT_LVL_LEVEL_HIGH;
191 break;
192
193 case IRQ_TYPE_LEVEL_LOW:
194 lvl_type = GPIO_INT_LVL_LEVEL_LOW;
195 break;
196
197 default:
198 return -EINVAL;
199 }
200
201 spin_lock_irqsave(&bank->lvl_lock[port], flags);
202
203 val = __raw_readl(GPIO_INT_LVL(gpio));
204 val &= ~(GPIO_INT_LVL_MASK << GPIO_BIT(gpio));
205 val |= lvl_type << GPIO_BIT(gpio);
206 __raw_writel(val, GPIO_INT_LVL(gpio));
207
208 spin_unlock_irqrestore(&bank->lvl_lock[port], flags);
209
210 if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
211 __irq_set_handler_locked(d->irq, handle_level_irq);
212 else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
213 __irq_set_handler_locked(d->irq, handle_edge_irq);
214
215 return 0;
216 }
217
tegra_gpio_irq_handler(unsigned int irq,struct irq_desc * desc)218 static void tegra_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
219 {
220 struct tegra_gpio_bank *bank;
221 int port;
222 int pin;
223 int unmasked = 0;
224
225 desc->irq_data.chip->irq_ack(&desc->irq_data);
226
227 bank = irq_get_handler_data(irq);
228
229 for (port = 0; port < 4; port++) {
230 int gpio = tegra_gpio_compose(bank->bank, port, 0);
231 unsigned long sta = __raw_readl(GPIO_INT_STA(gpio)) &
232 __raw_readl(GPIO_INT_ENB(gpio));
233 u32 lvl = __raw_readl(GPIO_INT_LVL(gpio));
234
235 for_each_set_bit(pin, &sta, 8) {
236 __raw_writel(1 << pin, GPIO_INT_CLR(gpio));
237
238 /* if gpio is edge triggered, clear condition
239 * before executing the hander so that we don't
240 * miss edges
241 */
242 if (lvl & (0x100 << pin)) {
243 unmasked = 1;
244 desc->irq_data.chip->irq_unmask(&desc->irq_data);
245 }
246
247 generic_handle_irq(gpio_to_irq(gpio + pin));
248 }
249 }
250
251 if (!unmasked)
252 desc->irq_data.chip->irq_unmask(&desc->irq_data);
253
254 }
255
256 #ifdef CONFIG_PM
tegra_gpio_resume(void)257 void tegra_gpio_resume(void)
258 {
259 unsigned long flags;
260 int b;
261 int p;
262
263 local_irq_save(flags);
264
265 for (b = 0; b < ARRAY_SIZE(tegra_gpio_banks); b++) {
266 struct tegra_gpio_bank *bank = &tegra_gpio_banks[b];
267
268 for (p = 0; p < ARRAY_SIZE(bank->oe); p++) {
269 unsigned int gpio = (b<<5) | (p<<3);
270 __raw_writel(bank->cnf[p], GPIO_CNF(gpio));
271 __raw_writel(bank->out[p], GPIO_OUT(gpio));
272 __raw_writel(bank->oe[p], GPIO_OE(gpio));
273 __raw_writel(bank->int_lvl[p], GPIO_INT_LVL(gpio));
274 __raw_writel(bank->int_enb[p], GPIO_INT_ENB(gpio));
275 }
276 }
277
278 local_irq_restore(flags);
279 }
280
tegra_gpio_suspend(void)281 void tegra_gpio_suspend(void)
282 {
283 unsigned long flags;
284 int b;
285 int p;
286
287 local_irq_save(flags);
288 for (b = 0; b < ARRAY_SIZE(tegra_gpio_banks); b++) {
289 struct tegra_gpio_bank *bank = &tegra_gpio_banks[b];
290
291 for (p = 0; p < ARRAY_SIZE(bank->oe); p++) {
292 unsigned int gpio = (b<<5) | (p<<3);
293 bank->cnf[p] = __raw_readl(GPIO_CNF(gpio));
294 bank->out[p] = __raw_readl(GPIO_OUT(gpio));
295 bank->oe[p] = __raw_readl(GPIO_OE(gpio));
296 bank->int_enb[p] = __raw_readl(GPIO_INT_ENB(gpio));
297 bank->int_lvl[p] = __raw_readl(GPIO_INT_LVL(gpio));
298 }
299 }
300 local_irq_restore(flags);
301 }
302
tegra_gpio_wake_enable(struct irq_data * d,unsigned int enable)303 static int tegra_gpio_wake_enable(struct irq_data *d, unsigned int enable)
304 {
305 struct tegra_gpio_bank *bank = irq_data_get_irq_chip_data(d);
306 return irq_set_irq_wake(bank->irq, enable);
307 }
308 #endif
309
310 static struct irq_chip tegra_gpio_irq_chip = {
311 .name = "GPIO",
312 .irq_ack = tegra_gpio_irq_ack,
313 .irq_mask = tegra_gpio_irq_mask,
314 .irq_unmask = tegra_gpio_irq_unmask,
315 .irq_set_type = tegra_gpio_irq_set_type,
316 #ifdef CONFIG_PM
317 .irq_set_wake = tegra_gpio_wake_enable,
318 #endif
319 };
320
321
322 /* This lock class tells lockdep that GPIO irqs are in a different
323 * category than their parents, so it won't report false recursion.
324 */
325 static struct lock_class_key gpio_lock_class;
326
tegra_gpio_init(void)327 static int __init tegra_gpio_init(void)
328 {
329 struct tegra_gpio_bank *bank;
330 int i;
331 int j;
332
333 for (i = 0; i < 7; i++) {
334 for (j = 0; j < 4; j++) {
335 int gpio = tegra_gpio_compose(i, j, 0);
336 __raw_writel(0x00, GPIO_INT_ENB(gpio));
337 }
338 }
339
340 gpiochip_add(&tegra_gpio_chip);
341
342 for (i = INT_GPIO_BASE; i < (INT_GPIO_BASE + TEGRA_NR_GPIOS); i++) {
343 bank = &tegra_gpio_banks[GPIO_BANK(irq_to_gpio(i))];
344
345 irq_set_lockdep_class(i, &gpio_lock_class);
346 irq_set_chip_data(i, bank);
347 irq_set_chip_and_handler(i, &tegra_gpio_irq_chip,
348 handle_simple_irq);
349 set_irq_flags(i, IRQF_VALID);
350 }
351
352 for (i = 0; i < ARRAY_SIZE(tegra_gpio_banks); i++) {
353 bank = &tegra_gpio_banks[i];
354
355 irq_set_chained_handler(bank->irq, tegra_gpio_irq_handler);
356 irq_set_handler_data(bank->irq, bank);
357
358 for (j = 0; j < 4; j++)
359 spin_lock_init(&bank->lvl_lock[j]);
360 }
361
362 return 0;
363 }
364
365 postcore_initcall(tegra_gpio_init);
366
tegra_gpio_config(struct tegra_gpio_table * table,int num)367 void __init tegra_gpio_config(struct tegra_gpio_table *table, int num)
368 {
369 int i;
370
371 for (i = 0; i < num; i++) {
372 int gpio = table[i].gpio;
373
374 if (table[i].enable)
375 tegra_gpio_enable(gpio);
376 else
377 tegra_gpio_disable(gpio);
378 }
379 }
380
381 #ifdef CONFIG_DEBUG_FS
382
383 #include <linux/debugfs.h>
384 #include <linux/seq_file.h>
385
dbg_gpio_show(struct seq_file * s,void * unused)386 static int dbg_gpio_show(struct seq_file *s, void *unused)
387 {
388 int i;
389 int j;
390
391 for (i = 0; i < 7; i++) {
392 for (j = 0; j < 4; j++) {
393 int gpio = tegra_gpio_compose(i, j, 0);
394 seq_printf(s,
395 "%d:%d %02x %02x %02x %02x %02x %02x %06x\n",
396 i, j,
397 __raw_readl(GPIO_CNF(gpio)),
398 __raw_readl(GPIO_OE(gpio)),
399 __raw_readl(GPIO_OUT(gpio)),
400 __raw_readl(GPIO_IN(gpio)),
401 __raw_readl(GPIO_INT_STA(gpio)),
402 __raw_readl(GPIO_INT_ENB(gpio)),
403 __raw_readl(GPIO_INT_LVL(gpio)));
404 }
405 }
406 return 0;
407 }
408
dbg_gpio_open(struct inode * inode,struct file * file)409 static int dbg_gpio_open(struct inode *inode, struct file *file)
410 {
411 return single_open(file, dbg_gpio_show, &inode->i_private);
412 }
413
414 static const struct file_operations debug_fops = {
415 .open = dbg_gpio_open,
416 .read = seq_read,
417 .llseek = seq_lseek,
418 .release = single_release,
419 };
420
tegra_gpio_debuginit(void)421 static int __init tegra_gpio_debuginit(void)
422 {
423 (void) debugfs_create_file("tegra_gpio", S_IRUGO,
424 NULL, NULL, &debug_fops);
425 return 0;
426 }
427 late_initcall(tegra_gpio_debuginit);
428 #endif
429