1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * TI DaVinci GPIO Support
5 * Copyright (c) 2006-2007 David Brownell
6 * Copyright (c) 2007, MontaVista Software, Inc. <source@mvista.com>
9 #include <linux/gpio/driver.h>
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/clk.h>
13 #include <linux/err.h>
15 #include <linux/irq.h>
16 #include <linux/irqdomain.h>
17 #include <linux/module.h>
18 #include <linux/pinctrl/consumer.h>
19 #include <linux/platform_device.h>
20 #include <linux/property.h>
21 #include <linux/irqchip/chained_irq.h>
22 #include <linux/spinlock.h>
23 #include <linux/pm_runtime.h>
25 #define MAX_REGS_BANKS 5
26 #define MAX_INT_PER_BANK 32
28 struct davinci_gpio_regs {
41 typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq);
43 #define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */
45 static void __iomem *gpio_base;
46 static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0};
48 struct davinci_gpio_irq_data {
50 struct davinci_gpio_controller *chip;
54 struct davinci_gpio_controller {
55 struct gpio_chip chip;
56 struct irq_domain *irq_domain;
57 /* Serialize access to GPIO registers */
59 void __iomem *regs[MAX_REGS_BANKS];
61 int irqs[MAX_INT_PER_BANK];
62 struct davinci_gpio_regs context[MAX_REGS_BANKS];
66 static inline u32 __gpio_mask(unsigned gpio)
68 return 1 << (gpio % 32);
71 static int davinci_gpio_irq_setup(struct platform_device *pdev);
73 /*--------------------------------------------------------------------------*/
75 /* board setup code *MUST* setup pinmux and enable the GPIO clock. */
76 static inline int __davinci_direction(struct gpio_chip *chip,
77 unsigned offset, bool out, int value)
79 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
80 struct davinci_gpio_regs __iomem *g;
83 int bank = offset / 32;
84 u32 mask = __gpio_mask(offset);
87 spin_lock_irqsave(&d->lock, flags);
88 temp = readl_relaxed(&g->dir);
91 writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
95 writel_relaxed(temp, &g->dir);
96 spin_unlock_irqrestore(&d->lock, flags);
101 static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
103 return __davinci_direction(chip, offset, false, 0);
107 davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
109 return __davinci_direction(chip, offset, true, value);
113 * Read the pin's value (works even if it's set up as output);
114 * returns zero/nonzero.
116 * Note that changes are synched to the GPIO clock, so reading values back
117 * right after you've set them may give old values.
119 static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
121 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
122 struct davinci_gpio_regs __iomem *g;
123 int bank = offset / 32;
127 return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data));
131 * Assuming the pin is muxed as a gpio output, set its output value.
134 davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
136 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
137 struct davinci_gpio_regs __iomem *g;
138 int bank = offset / 32;
142 writel_relaxed(__gpio_mask(offset),
143 value ? &g->set_data : &g->clr_data);
148 static int davinci_gpio_probe(struct platform_device *pdev)
150 int bank, i, ret = 0;
151 unsigned int ngpio, nbank, nirq, gpio_unbanked;
152 struct davinci_gpio_controller *chips;
153 struct device *dev = &pdev->dev;
156 * The gpio banks conceptually expose a segmented bitmap,
157 * and "ngpio" is one more than the largest zero-based
158 * bit index that's valid.
160 ret = device_property_read_u32(dev, "ti,ngpio", &ngpio);
162 return dev_err_probe(dev, ret, "Failed to get the number of GPIOs\n");
164 return dev_err_probe(dev, -EINVAL, "How many GPIOs?\n");
167 * If there are unbanked interrupts then the number of
168 * interrupts is equal to number of gpios else all are banked so
169 * number of interrupts is equal to number of banks(each with 16 gpios)
171 ret = device_property_read_u32(dev, "ti,davinci-gpio-unbanked",
174 return dev_err_probe(dev, ret, "Failed to get the unbanked GPIOs property\n");
177 nirq = gpio_unbanked;
179 nirq = DIV_ROUND_UP(ngpio, 16);
181 if (nirq > MAX_INT_PER_BANK) {
182 dev_err(dev, "Too many IRQs!\n");
186 chips = devm_kzalloc(dev, sizeof(*chips), GFP_KERNEL);
190 gpio_base = devm_platform_ioremap_resource(pdev, 0);
191 if (IS_ERR(gpio_base))
192 return PTR_ERR(gpio_base);
194 for (i = 0; i < nirq; i++) {
195 chips->irqs[i] = platform_get_irq(pdev, i);
196 if (chips->irqs[i] < 0)
197 return chips->irqs[i];
200 chips->chip.label = dev_name(dev);
202 chips->chip.direction_input = davinci_direction_in;
203 chips->chip.get = davinci_gpio_get;
204 chips->chip.direction_output = davinci_direction_out;
205 chips->chip.set_rv = davinci_gpio_set;
207 chips->chip.ngpio = ngpio;
208 chips->chip.base = -1;
210 #ifdef CONFIG_OF_GPIO
211 chips->chip.parent = dev;
212 chips->chip.request = gpiochip_generic_request;
213 chips->chip.free = gpiochip_generic_free;
215 spin_lock_init(&chips->lock);
217 chips->gpio_unbanked = gpio_unbanked;
219 nbank = DIV_ROUND_UP(ngpio, 32);
220 for (bank = 0; bank < nbank; bank++)
221 chips->regs[bank] = gpio_base + offset_array[bank];
223 ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
227 platform_set_drvdata(pdev, chips);
228 ret = davinci_gpio_irq_setup(pdev);
235 /*--------------------------------------------------------------------------*/
237 * We expect irqs will normally be set up as input pins, but they can also be
238 * used as output pins ... which is convenient for testing.
240 * NOTE: The first few GPIOs also have direct INTC hookups in addition
241 * to their GPIOBNK0 irq, with a bit less overhead.
243 * All those INTC hookups (direct, plus several IRQ banks) can also
244 * serve as EDMA event triggers.
247 static void gpio_irq_mask(struct irq_data *d)
249 struct davinci_gpio_controller *chips = irq_data_get_irq_chip_data(d);
250 irq_hw_number_t hwirq = irqd_to_hwirq(d);
251 struct davinci_gpio_regs __iomem *g = chips->regs[hwirq / 32];
252 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
254 writel_relaxed(mask, &g->clr_falling);
255 writel_relaxed(mask, &g->clr_rising);
257 gpiochip_disable_irq(&chips->chip, hwirq);
260 static void gpio_irq_unmask(struct irq_data *d)
262 struct davinci_gpio_controller *chips = irq_data_get_irq_chip_data(d);
263 irq_hw_number_t hwirq = irqd_to_hwirq(d);
264 struct davinci_gpio_regs __iomem *g = chips->regs[hwirq / 32];
265 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
266 unsigned status = irqd_get_trigger_type(d);
268 gpiochip_enable_irq(&chips->chip, hwirq);
270 status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
272 status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
274 if (status & IRQ_TYPE_EDGE_FALLING)
275 writel_relaxed(mask, &g->set_falling);
276 if (status & IRQ_TYPE_EDGE_RISING)
277 writel_relaxed(mask, &g->set_rising);
280 static int gpio_irq_type(struct irq_data *d, unsigned trigger)
282 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
288 static const struct irq_chip gpio_irqchip = {
290 .irq_unmask = gpio_irq_unmask,
291 .irq_mask = gpio_irq_mask,
292 .irq_set_type = gpio_irq_type,
293 .flags = IRQCHIP_IMMUTABLE | IRQCHIP_SET_TYPE_MASKED | IRQCHIP_SKIP_SET_WAKE,
294 GPIOCHIP_IRQ_RESOURCE_HELPERS,
297 static void gpio_irq_handler(struct irq_desc *desc)
299 struct davinci_gpio_regs __iomem *g;
302 struct davinci_gpio_controller *d;
303 struct davinci_gpio_irq_data *irqdata;
305 irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc);
306 bank_num = irqdata->bank_num;
310 /* we only care about one bank */
311 if ((bank_num % 2) == 1)
314 /* temporarily mask (level sensitive) parent IRQ */
315 chained_irq_enter(irq_desc_get_chip(desc), desc);
319 irq_hw_number_t hw_irq;
322 status = readl_relaxed(&g->intstat) & mask;
325 writel_relaxed(status, &g->intstat);
327 /* now demux them to the right lowlevel handler */
332 /* Max number of gpios per controller is 144 so
333 * hw_irq will be in [0..143]
335 hw_irq = (bank_num / 2) * 32 + bit;
337 generic_handle_domain_irq(d->irq_domain, hw_irq);
340 chained_irq_exit(irq_desc_get_chip(desc), desc);
341 /* now it may re-trigger */
344 static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
346 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
349 return irq_create_mapping(d->irq_domain, offset);
354 static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
356 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
359 * NOTE: we assume for now that only irqs in the first gpio_chip
360 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
362 if (offset < d->gpio_unbanked)
363 return d->irqs[offset];
368 static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
370 struct davinci_gpio_controller *d;
371 struct davinci_gpio_regs __iomem *g;
374 d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data);
375 g = (struct davinci_gpio_regs __iomem *)d->regs[0];
376 for (i = 0; i < MAX_INT_PER_BANK; i++)
377 if (data->irq == d->irqs[i])
380 if (i == MAX_INT_PER_BANK)
383 mask = __gpio_mask(i);
385 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
388 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
389 ? &g->set_falling : &g->clr_falling);
390 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
391 ? &g->set_rising : &g->clr_rising);
397 davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
400 struct davinci_gpio_controller *chips =
401 (struct davinci_gpio_controller *)d->host_data;
403 irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
405 irq_set_irq_type(irq, IRQ_TYPE_NONE);
406 irq_set_chip_data(irq, (__force void *)chips);
407 irq_set_handler_data(irq, (void *)(uintptr_t)__gpio_mask(hw));
412 static const struct irq_domain_ops davinci_gpio_irq_ops = {
413 .map = davinci_gpio_irq_map,
414 .xlate = irq_domain_xlate_onetwocell,
417 static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
419 static struct irq_chip_type gpio_unbanked;
421 gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq));
423 return &gpio_unbanked.chip;
426 static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
428 static struct irq_chip gpio_unbanked;
430 gpio_unbanked = *irq_get_chip(irq);
431 return &gpio_unbanked;
434 static const struct of_device_id davinci_gpio_ids[];
437 * NOTE: for suspend/resume, probably best to make a platform_device with
438 * suspend_late/resume_resume calls hooking into results of the set_wake()
439 * calls ... so if no gpios are wakeup events the clock can be disabled,
440 * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
441 * (dm6446) can be set appropriately for GPIOV33 pins.
444 static int davinci_gpio_irq_setup(struct platform_device *pdev)
451 struct device *dev = &pdev->dev;
452 struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
453 struct davinci_gpio_regs __iomem *g;
454 struct irq_domain *irq_domain = NULL;
455 struct irq_chip *irq_chip;
456 struct davinci_gpio_irq_data *irqdata;
457 gpio_get_irq_chip_cb_t gpio_get_irq_chip;
460 * Use davinci_gpio_get_irq_chip by default to handle non DT cases
462 gpio_get_irq_chip = davinci_gpio_get_irq_chip;
464 gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)device_get_match_data(dev);
466 ngpio = chips->chip.ngpio;
468 clk = devm_clk_get_enabled(dev, "gpio");
470 dev_err(dev, "Error %ld getting gpio clock\n", PTR_ERR(clk));
474 if (!chips->gpio_unbanked) {
475 irq = devm_irq_alloc_descs(dev, -1, 0, ngpio, 0);
477 dev_err(dev, "Couldn't allocate IRQ numbers\n");
481 irq_domain = irq_domain_create_legacy(of_fwnode_handle(dev->of_node), ngpio, irq, 0,
482 &davinci_gpio_irq_ops, chips);
484 dev_err(dev, "Couldn't register an IRQ domain\n");
490 * Arrange gpiod_to_irq() support, handling either direct IRQs or
491 * banked IRQs. Having GPIOs in the first GPIO bank use direct
492 * IRQs, while the others use banked IRQs, would need some setup
493 * tweaks to recognize hardware which can do that.
495 chips->chip.to_irq = gpio_to_irq_banked;
496 chips->irq_domain = irq_domain;
499 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
500 * controller only handling trigger modes. We currently assume no
501 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
503 if (chips->gpio_unbanked) {
504 /* pass "bank 0" GPIO IRQs to AINTC */
505 chips->chip.to_irq = gpio_to_irq_unbanked;
507 binten = GENMASK(chips->gpio_unbanked / 16, 0);
509 /* AINTC handles mask/unmask; GPIO handles triggering */
510 irq = chips->irqs[0];
511 irq_chip = gpio_get_irq_chip(irq);
512 irq_chip->name = "GPIO-AINTC";
513 irq_chip->irq_set_type = gpio_irq_type_unbanked;
515 /* default trigger: both edges */
517 writel_relaxed(~0, &g->set_falling);
518 writel_relaxed(~0, &g->set_rising);
520 /* set the direct IRQs up to use that irqchip */
521 for (gpio = 0; gpio < chips->gpio_unbanked; gpio++) {
522 irq_set_chip(chips->irqs[gpio], irq_chip);
523 irq_set_handler_data(chips->irqs[gpio], chips);
524 irq_set_status_flags(chips->irqs[gpio],
532 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
533 * then chain through our own handler.
535 for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 16) {
536 /* disabled by default, enabled only as needed
537 * There are register sets for 32 GPIOs. 2 banks of 16
538 * GPIOs are covered by each set of registers hence divide by 2
540 g = chips->regs[bank / 2];
541 writel_relaxed(~0, &g->clr_falling);
542 writel_relaxed(~0, &g->clr_rising);
545 * Each chip handles 32 gpios, and each irq bank consists of 16
546 * gpio irqs. Pass the irq bank's corresponding controller to
547 * the chained irq handler.
549 irqdata = devm_kzalloc(&pdev->dev,
551 davinci_gpio_irq_data),
557 irqdata->bank_num = bank;
558 irqdata->chip = chips;
560 irq_set_chained_handler_and_data(chips->irqs[bank],
561 gpio_irq_handler, irqdata);
568 * BINTEN -- per-bank interrupt enable. genirq would also let these
569 * bits be set/cleared dynamically.
571 writel_relaxed(binten, gpio_base + BINTEN);
576 static void davinci_gpio_save_context(struct davinci_gpio_controller *chips,
579 struct davinci_gpio_regs __iomem *g;
580 struct davinci_gpio_regs *context;
584 base = chips->regs[0] - offset_array[0];
585 chips->binten_context = readl_relaxed(base + BINTEN);
587 for (bank = 0; bank < nbank; bank++) {
588 g = chips->regs[bank];
589 context = &chips->context[bank];
590 context->dir = readl_relaxed(&g->dir);
591 context->set_data = readl_relaxed(&g->set_data);
592 context->set_rising = readl_relaxed(&g->set_rising);
593 context->set_falling = readl_relaxed(&g->set_falling);
596 /* Clear all interrupt status registers */
597 writel_relaxed(GENMASK(31, 0), &g->intstat);
600 static void davinci_gpio_restore_context(struct davinci_gpio_controller *chips,
603 struct davinci_gpio_regs __iomem *g;
604 struct davinci_gpio_regs *context;
608 base = chips->regs[0] - offset_array[0];
610 if (readl_relaxed(base + BINTEN) != chips->binten_context)
611 writel_relaxed(chips->binten_context, base + BINTEN);
613 for (bank = 0; bank < nbank; bank++) {
614 g = chips->regs[bank];
615 context = &chips->context[bank];
616 if (readl_relaxed(&g->dir) != context->dir)
617 writel_relaxed(context->dir, &g->dir);
618 if (readl_relaxed(&g->set_data) != context->set_data)
619 writel_relaxed(context->set_data, &g->set_data);
620 if (readl_relaxed(&g->set_rising) != context->set_rising)
621 writel_relaxed(context->set_rising, &g->set_rising);
622 if (readl_relaxed(&g->set_falling) != context->set_falling)
623 writel_relaxed(context->set_falling, &g->set_falling);
627 static int davinci_gpio_suspend(struct device *dev)
629 struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
630 u32 nbank = DIV_ROUND_UP(chips->chip.ngpio, 32);
632 davinci_gpio_save_context(chips, nbank);
637 static int davinci_gpio_resume(struct device *dev)
639 struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
640 u32 nbank = DIV_ROUND_UP(chips->chip.ngpio, 32);
642 davinci_gpio_restore_context(chips, nbank);
647 static DEFINE_SIMPLE_DEV_PM_OPS(davinci_gpio_dev_pm_ops, davinci_gpio_suspend,
648 davinci_gpio_resume);
650 static const struct of_device_id davinci_gpio_ids[] = {
651 { .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip},
652 { .compatible = "ti,am654-gpio", keystone_gpio_get_irq_chip},
653 { .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
656 MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
658 static struct platform_driver davinci_gpio_driver = {
659 .probe = davinci_gpio_probe,
661 .name = "davinci_gpio",
662 .pm = pm_sleep_ptr(&davinci_gpio_dev_pm_ops),
663 .of_match_table = davinci_gpio_ids,
668 * GPIO driver registration needs to be done before machine_init functions
669 * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
671 static int __init davinci_gpio_drv_reg(void)
673 return platform_driver_register(&davinci_gpio_driver);
675 postcore_initcall(davinci_gpio_drv_reg);
677 static void __exit davinci_gpio_exit(void)
679 platform_driver_unregister(&davinci_gpio_driver);
681 module_exit(davinci_gpio_exit);
683 MODULE_AUTHOR("Jan Kotas <jank@cadence.com>");
684 MODULE_DESCRIPTION("DAVINCI GPIO driver");
685 MODULE_LICENSE("GPL");
686 MODULE_ALIAS("platform:gpio-davinci");