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1/*
2 * TI DaVinci GPIO Support
3 *
4 * Copyright (c) 2006-2007 David Brownell
5 * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13#include <linux/errno.h>
14#include <linux/kernel.h>
15#include <linux/clk.h>
16#include <linux/err.h>
17#include <linux/io.h>
18
19#include <mach/gpio.h>
20
21#include <asm/mach/irq.h>
22
23struct davinci_gpio_regs {
24 u32 dir;
25 u32 out_data;
26 u32 set_data;
27 u32 clr_data;
28 u32 in_data;
29 u32 set_rising;
30 u32 clr_rising;
31 u32 set_falling;
32 u32 clr_falling;
33 u32 intstat;
34};
35
36#define chip2controller(chip) \
37 container_of(chip, struct davinci_gpio_controller, chip)
38
39static struct davinci_gpio_controller chips[DIV_ROUND_UP(DAVINCI_N_GPIO, 32)];
40static void __iomem *gpio_base;
41
42static struct davinci_gpio_regs __iomem __init *gpio2regs(unsigned gpio)
43{
44 void __iomem *ptr;
45
46 if (gpio < 32 * 1)
47 ptr = gpio_base + 0x10;
48 else if (gpio < 32 * 2)
49 ptr = gpio_base + 0x38;
50 else if (gpio < 32 * 3)
51 ptr = gpio_base + 0x60;
52 else if (gpio < 32 * 4)
53 ptr = gpio_base + 0x88;
54 else if (gpio < 32 * 5)
55 ptr = gpio_base + 0xb0;
56 else
57 ptr = NULL;
58 return ptr;
59}
60
61static inline struct davinci_gpio_regs __iomem *irq2regs(int irq)
62{
63 struct davinci_gpio_regs __iomem *g;
64
65 g = (__force struct davinci_gpio_regs __iomem *)irq_get_chip_data(irq);
66
67 return g;
68}
69
70static int __init davinci_gpio_irq_setup(void);
71
72/*--------------------------------------------------------------------------*/
73
74/* board setup code *MUST* setup pinmux and enable the GPIO clock. */
75static inline int __davinci_direction(struct gpio_chip *chip,
76 unsigned offset, bool out, int value)
77{
78 struct davinci_gpio_controller *d = chip2controller(chip);
79 struct davinci_gpio_regs __iomem *g = d->regs;
80 unsigned long flags;
81 u32 temp;
82 u32 mask = 1 << offset;
83
84 spin_lock_irqsave(&d->lock, flags);
85 temp = __raw_readl(&g->dir);
86 if (out) {
87 temp &= ~mask;
88 __raw_writel(mask, value ? &g->set_data : &g->clr_data);
89 } else {
90 temp |= mask;
91 }
92 __raw_writel(temp, &g->dir);
93 spin_unlock_irqrestore(&d->lock, flags);
94
95 return 0;
96}
97
98static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
99{
100 return __davinci_direction(chip, offset, false, 0);
101}
102
103static int
104davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
105{
106 return __davinci_direction(chip, offset, true, value);
107}
108
109/*
110 * Read the pin's value (works even if it's set up as output);
111 * returns zero/nonzero.
112 *
113 * Note that changes are synched to the GPIO clock, so reading values back
114 * right after you've set them may give old values.
115 */
116static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
117{
118 struct davinci_gpio_controller *d = chip2controller(chip);
119 struct davinci_gpio_regs __iomem *g = d->regs;
120
121 return (1 << offset) & __raw_readl(&g->in_data);
122}
123
124/*
125 * Assuming the pin is muxed as a gpio output, set its output value.
126 */
127static void
128davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
129{
130 struct davinci_gpio_controller *d = chip2controller(chip);
131 struct davinci_gpio_regs __iomem *g = d->regs;
132
133 __raw_writel((1 << offset), value ? &g->set_data : &g->clr_data);
134}
135
136static int __init davinci_gpio_setup(void)
137{
138 int i, base;
139 unsigned ngpio;
140 struct davinci_soc_info *soc_info = &davinci_soc_info;
141 struct davinci_gpio_regs *regs;
142
143 if (soc_info->gpio_type != GPIO_TYPE_DAVINCI)
144 return 0;
145
146 /*
147 * The gpio banks conceptually expose a segmented bitmap,
148 * and "ngpio" is one more than the largest zero-based
149 * bit index that's valid.
150 */
151 ngpio = soc_info->gpio_num;
152 if (ngpio == 0) {
153 pr_err("GPIO setup: how many GPIOs?\n");
154 return -EINVAL;
155 }
156
157 if (WARN_ON(DAVINCI_N_GPIO < ngpio))
158 ngpio = DAVINCI_N_GPIO;
159
160 gpio_base = ioremap(soc_info->gpio_base, SZ_4K);
161 if (WARN_ON(!gpio_base))
162 return -ENOMEM;
163
164 for (i = 0, base = 0; base < ngpio; i++, base += 32) {
165 chips[i].chip.label = "DaVinci";
166
167 chips[i].chip.direction_input = davinci_direction_in;
168 chips[i].chip.get = davinci_gpio_get;
169 chips[i].chip.direction_output = davinci_direction_out;
170 chips[i].chip.set = davinci_gpio_set;
171
172 chips[i].chip.base = base;
173 chips[i].chip.ngpio = ngpio - base;
174 if (chips[i].chip.ngpio > 32)
175 chips[i].chip.ngpio = 32;
176
177 spin_lock_init(&chips[i].lock);
178
179 regs = gpio2regs(base);
180 chips[i].regs = regs;
181 chips[i].set_data = ®s->set_data;
182 chips[i].clr_data = ®s->clr_data;
183 chips[i].in_data = ®s->in_data;
184
185 gpiochip_add(&chips[i].chip);
186 }
187
188 soc_info->gpio_ctlrs = chips;
189 soc_info->gpio_ctlrs_num = DIV_ROUND_UP(ngpio, 32);
190
191 davinci_gpio_irq_setup();
192 return 0;
193}
194pure_initcall(davinci_gpio_setup);
195
196/*--------------------------------------------------------------------------*/
197/*
198 * We expect irqs will normally be set up as input pins, but they can also be
199 * used as output pins ... which is convenient for testing.
200 *
201 * NOTE: The first few GPIOs also have direct INTC hookups in addition
202 * to their GPIOBNK0 irq, with a bit less overhead.
203 *
204 * All those INTC hookups (direct, plus several IRQ banks) can also
205 * serve as EDMA event triggers.
206 */
207
208static void gpio_irq_disable(struct irq_data *d)
209{
210 struct davinci_gpio_regs __iomem *g = irq2regs(d->irq);
211 u32 mask = (u32) irq_data_get_irq_handler_data(d);
212
213 __raw_writel(mask, &g->clr_falling);
214 __raw_writel(mask, &g->clr_rising);
215}
216
217static void gpio_irq_enable(struct irq_data *d)
218{
219 struct davinci_gpio_regs __iomem *g = irq2regs(d->irq);
220 u32 mask = (u32) irq_data_get_irq_handler_data(d);
221 unsigned status = irqd_get_trigger_type(d);
222
223 status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
224 if (!status)
225 status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
226
227 if (status & IRQ_TYPE_EDGE_FALLING)
228 __raw_writel(mask, &g->set_falling);
229 if (status & IRQ_TYPE_EDGE_RISING)
230 __raw_writel(mask, &g->set_rising);
231}
232
233static int gpio_irq_type(struct irq_data *d, unsigned trigger)
234{
235 struct davinci_gpio_regs __iomem *g = irq2regs(d->irq);
236 u32 mask = (u32) irq_data_get_irq_handler_data(d);
237
238 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
239 return -EINVAL;
240
241 return 0;
242}
243
244static struct irq_chip gpio_irqchip = {
245 .name = "GPIO",
246 .irq_enable = gpio_irq_enable,
247 .irq_disable = gpio_irq_disable,
248 .irq_set_type = gpio_irq_type,
249 .flags = IRQCHIP_SET_TYPE_MASKED,
250};
251
252static void
253gpio_irq_handler(unsigned irq, struct irq_desc *desc)
254{
255 struct davinci_gpio_regs __iomem *g;
256 u32 mask = 0xffff;
257 struct davinci_gpio_controller *d;
258
259 d = (struct davinci_gpio_controller *)irq_desc_get_handler_data(desc);
260 g = (struct davinci_gpio_regs __iomem *)d->regs;
261
262 /* we only care about one bank */
263 if (irq & 1)
264 mask <<= 16;
265
266 /* temporarily mask (level sensitive) parent IRQ */
267 desc->irq_data.chip->irq_mask(&desc->irq_data);
268 desc->irq_data.chip->irq_ack(&desc->irq_data);
269 while (1) {
270 u32 status;
271 int n;
272 int res;
273
274 /* ack any irqs */
275 status = __raw_readl(&g->intstat) & mask;
276 if (!status)
277 break;
278 __raw_writel(status, &g->intstat);
279
280 /* now demux them to the right lowlevel handler */
281 n = d->irq_base;
282 if (irq & 1) {
283 n += 16;
284 status >>= 16;
285 }
286
287 while (status) {
288 res = ffs(status);
289 n += res;
290 generic_handle_irq(n - 1);
291 status >>= res;
292 }
293 }
294 desc->irq_data.chip->irq_unmask(&desc->irq_data);
295 /* now it may re-trigger */
296}
297
298static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
299{
300 struct davinci_gpio_controller *d = chip2controller(chip);
301
302 if (d->irq_base >= 0)
303 return d->irq_base + offset;
304 else
305 return -ENODEV;
306}
307
308static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
309{
310 struct davinci_soc_info *soc_info = &davinci_soc_info;
311
312 /* NOTE: we assume for now that only irqs in the first gpio_chip
313 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
314 */
315 if (offset < soc_info->gpio_unbanked)
316 return soc_info->gpio_irq + offset;
317 else
318 return -ENODEV;
319}
320
321static int gpio_irq_type_unbanked(struct irq_data *d, unsigned trigger)
322{
323 struct davinci_gpio_regs __iomem *g = irq2regs(d->irq);
324 u32 mask = (u32) irq_data_get_irq_handler_data(d);
325
326 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
327 return -EINVAL;
328
329 __raw_writel(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
330 ? &g->set_falling : &g->clr_falling);
331 __raw_writel(mask, (trigger & IRQ_TYPE_EDGE_RISING)
332 ? &g->set_rising : &g->clr_rising);
333
334 return 0;
335}
336
337/*
338 * NOTE: for suspend/resume, probably best to make a platform_device with
339 * suspend_late/resume_resume calls hooking into results of the set_wake()
340 * calls ... so if no gpios are wakeup events the clock can be disabled,
341 * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
342 * (dm6446) can be set appropriately for GPIOV33 pins.
343 */
344
345static int __init davinci_gpio_irq_setup(void)
346{
347 unsigned gpio, irq, bank;
348 struct clk *clk;
349 u32 binten = 0;
350 unsigned ngpio, bank_irq;
351 struct davinci_soc_info *soc_info = &davinci_soc_info;
352 struct davinci_gpio_regs __iomem *g;
353
354 ngpio = soc_info->gpio_num;
355
356 bank_irq = soc_info->gpio_irq;
357 if (bank_irq == 0) {
358 printk(KERN_ERR "Don't know first GPIO bank IRQ.\n");
359 return -EINVAL;
360 }
361
362 clk = clk_get(NULL, "gpio");
363 if (IS_ERR(clk)) {
364 printk(KERN_ERR "Error %ld getting gpio clock?\n",
365 PTR_ERR(clk));
366 return PTR_ERR(clk);
367 }
368 clk_enable(clk);
369
370 /* Arrange gpio_to_irq() support, handling either direct IRQs or
371 * banked IRQs. Having GPIOs in the first GPIO bank use direct
372 * IRQs, while the others use banked IRQs, would need some setup
373 * tweaks to recognize hardware which can do that.
374 */
375 for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 32) {
376 chips[bank].chip.to_irq = gpio_to_irq_banked;
377 chips[bank].irq_base = soc_info->gpio_unbanked
378 ? -EINVAL
379 : (soc_info->intc_irq_num + gpio);
380 }
381
382 /*
383 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
384 * controller only handling trigger modes. We currently assume no
385 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
386 */
387 if (soc_info->gpio_unbanked) {
388 static struct irq_chip gpio_irqchip_unbanked;
389
390 /* pass "bank 0" GPIO IRQs to AINTC */
391 chips[0].chip.to_irq = gpio_to_irq_unbanked;
392 binten = BIT(0);
393
394 /* AINTC handles mask/unmask; GPIO handles triggering */
395 irq = bank_irq;
396 gpio_irqchip_unbanked = *irq_get_chip(irq);
397 gpio_irqchip_unbanked.name = "GPIO-AINTC";
398 gpio_irqchip_unbanked.irq_set_type = gpio_irq_type_unbanked;
399
400 /* default trigger: both edges */
401 g = gpio2regs(0);
402 __raw_writel(~0, &g->set_falling);
403 __raw_writel(~0, &g->set_rising);
404
405 /* set the direct IRQs up to use that irqchip */
406 for (gpio = 0; gpio < soc_info->gpio_unbanked; gpio++, irq++) {
407 irq_set_chip(irq, &gpio_irqchip_unbanked);
408 irq_set_handler_data(irq, (void *)__gpio_mask(gpio));
409 irq_set_chip_data(irq, (__force void *)g);
410 irq_set_status_flags(irq, IRQ_TYPE_EDGE_BOTH);
411 }
412
413 goto done;
414 }
415
416 /*
417 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
418 * then chain through our own handler.
419 */
420 for (gpio = 0, irq = gpio_to_irq(0), bank = 0;
421 gpio < ngpio;
422 bank++, bank_irq++) {
423 unsigned i;
424
425 /* disabled by default, enabled only as needed */
426 g = gpio2regs(gpio);
427 __raw_writel(~0, &g->clr_falling);
428 __raw_writel(~0, &g->clr_rising);
429
430 /* set up all irqs in this bank */
431 irq_set_chained_handler(bank_irq, gpio_irq_handler);
432
433 /*
434 * Each chip handles 32 gpios, and each irq bank consists of 16
435 * gpio irqs. Pass the irq bank's corresponding controller to
436 * the chained irq handler.
437 */
438 irq_set_handler_data(bank_irq, &chips[gpio / 32]);
439
440 for (i = 0; i < 16 && gpio < ngpio; i++, irq++, gpio++) {
441 irq_set_chip(irq, &gpio_irqchip);
442 irq_set_chip_data(irq, (__force void *)g);
443 irq_set_handler_data(irq, (void *)__gpio_mask(gpio));
444 irq_set_handler(irq, handle_simple_irq);
445 set_irq_flags(irq, IRQF_VALID);
446 }
447
448 binten |= BIT(bank);
449 }
450
451done:
452 /* BINTEN -- per-bank interrupt enable. genirq would also let these
453 * bits be set/cleared dynamically.
454 */
455 __raw_writel(binten, gpio_base + 0x08);
456
457 printk(KERN_INFO "DaVinci: %d gpio irqs\n", irq - gpio_to_irq(0));
458
459 return 0;
460}