1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * TI DaVinci GPIO Support
5 * Copyright (c) 2006-2007 David Brownell
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>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/platform_device.h>
21 #include <linux/platform_data/gpio-davinci.h>
22 #include <linux/property.h>
23 #include <linux/irqchip/chained_irq.h>
24 #include <linux/spinlock.h>
25 #include <linux/pm_runtime.h>
27 #define MAX_REGS_BANKS 5
28 #define MAX_INT_PER_BANK 32
30 struct davinci_gpio_regs {
43 typedef struct irq_chip *(*gpio_get_irq_chip_cb_t)(unsigned int irq);
45 #define BINTEN 0x8 /* GPIO Interrupt Per-Bank Enable Register */
47 static void __iomem *gpio_base;
48 static unsigned int offset_array[5] = {0x10, 0x38, 0x60, 0x88, 0xb0};
50 struct davinci_gpio_irq_data {
52 struct davinci_gpio_controller *chip;
56 struct davinci_gpio_controller {
57 struct gpio_chip chip;
58 struct irq_domain *irq_domain;
59 /* Serialize access to GPIO registers */
61 void __iomem *regs[MAX_REGS_BANKS];
63 int irqs[MAX_INT_PER_BANK];
64 struct davinci_gpio_regs context[MAX_REGS_BANKS];
68 static inline u32 __gpio_mask(unsigned gpio)
70 return 1 << (gpio % 32);
73 static inline struct davinci_gpio_regs __iomem *irq2regs(struct irq_data *d)
75 struct davinci_gpio_regs __iomem *g;
77 g = (__force struct davinci_gpio_regs __iomem *)irq_data_get_irq_chip_data(d);
82 static int davinci_gpio_irq_setup(struct platform_device *pdev);
84 /*--------------------------------------------------------------------------*/
86 /* board setup code *MUST* setup pinmux and enable the GPIO clock. */
87 static inline int __davinci_direction(struct gpio_chip *chip,
88 unsigned offset, bool out, int value)
90 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
91 struct davinci_gpio_regs __iomem *g;
94 int bank = offset / 32;
95 u32 mask = __gpio_mask(offset);
98 spin_lock_irqsave(&d->lock, flags);
99 temp = readl_relaxed(&g->dir);
102 writel_relaxed(mask, value ? &g->set_data : &g->clr_data);
106 writel_relaxed(temp, &g->dir);
107 spin_unlock_irqrestore(&d->lock, flags);
112 static int davinci_direction_in(struct gpio_chip *chip, unsigned offset)
114 return __davinci_direction(chip, offset, false, 0);
118 davinci_direction_out(struct gpio_chip *chip, unsigned offset, int value)
120 return __davinci_direction(chip, offset, true, value);
124 * Read the pin's value (works even if it's set up as output);
125 * returns zero/nonzero.
127 * Note that changes are synched to the GPIO clock, so reading values back
128 * right after you've set them may give old values.
130 static int davinci_gpio_get(struct gpio_chip *chip, unsigned offset)
132 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
133 struct davinci_gpio_regs __iomem *g;
134 int bank = offset / 32;
138 return !!(__gpio_mask(offset) & readl_relaxed(&g->in_data));
142 * Assuming the pin is muxed as a gpio output, set its output value.
145 davinci_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
147 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
148 struct davinci_gpio_regs __iomem *g;
149 int bank = offset / 32;
153 writel_relaxed(__gpio_mask(offset),
154 value ? &g->set_data : &g->clr_data);
157 static struct davinci_gpio_platform_data *
158 davinci_gpio_get_pdata(struct platform_device *pdev)
160 struct device_node *dn = pdev->dev.of_node;
161 struct davinci_gpio_platform_data *pdata;
165 if (!IS_ENABLED(CONFIG_OF) || !pdev->dev.of_node)
166 return dev_get_platdata(&pdev->dev);
168 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
172 ret = of_property_read_u32(dn, "ti,ngpio", &val);
178 ret = of_property_read_u32(dn, "ti,davinci-gpio-unbanked", &val);
182 pdata->gpio_unbanked = val;
187 dev_err(&pdev->dev, "Populating pdata from DT failed: err %d\n", ret);
191 static int davinci_gpio_probe(struct platform_device *pdev)
193 int bank, i, ret = 0;
194 unsigned int ngpio, nbank, nirq;
195 struct davinci_gpio_controller *chips;
196 struct davinci_gpio_platform_data *pdata;
197 struct device *dev = &pdev->dev;
199 pdata = davinci_gpio_get_pdata(pdev);
201 dev_err(dev, "No platform data found\n");
205 dev->platform_data = pdata;
208 * The gpio banks conceptually expose a segmented bitmap,
209 * and "ngpio" is one more than the largest zero-based
210 * bit index that's valid.
212 ngpio = pdata->ngpio;
214 dev_err(dev, "How many GPIOs?\n");
219 * If there are unbanked interrupts then the number of
220 * interrupts is equal to number of gpios else all are banked so
221 * number of interrupts is equal to number of banks(each with 16 gpios)
223 if (pdata->gpio_unbanked)
224 nirq = pdata->gpio_unbanked;
226 nirq = DIV_ROUND_UP(ngpio, 16);
228 chips = devm_kzalloc(dev, sizeof(*chips), GFP_KERNEL);
232 gpio_base = devm_platform_ioremap_resource(pdev, 0);
233 if (IS_ERR(gpio_base))
234 return PTR_ERR(gpio_base);
236 for (i = 0; i < nirq; i++) {
237 chips->irqs[i] = platform_get_irq(pdev, i);
238 if (chips->irqs[i] < 0)
239 return chips->irqs[i];
242 chips->chip.label = dev_name(dev);
244 chips->chip.direction_input = davinci_direction_in;
245 chips->chip.get = davinci_gpio_get;
246 chips->chip.direction_output = davinci_direction_out;
247 chips->chip.set = davinci_gpio_set;
249 chips->chip.ngpio = ngpio;
250 chips->chip.base = pdata->no_auto_base ? pdata->base : -1;
252 #ifdef CONFIG_OF_GPIO
253 chips->chip.parent = dev;
254 chips->chip.request = gpiochip_generic_request;
255 chips->chip.free = gpiochip_generic_free;
257 spin_lock_init(&chips->lock);
259 nbank = DIV_ROUND_UP(ngpio, 32);
260 for (bank = 0; bank < nbank; bank++)
261 chips->regs[bank] = gpio_base + offset_array[bank];
263 ret = devm_gpiochip_add_data(dev, &chips->chip, chips);
267 platform_set_drvdata(pdev, chips);
268 ret = davinci_gpio_irq_setup(pdev);
275 /*--------------------------------------------------------------------------*/
277 * We expect irqs will normally be set up as input pins, but they can also be
278 * used as output pins ... which is convenient for testing.
280 * NOTE: The first few GPIOs also have direct INTC hookups in addition
281 * to their GPIOBNK0 irq, with a bit less overhead.
283 * All those INTC hookups (direct, plus several IRQ banks) can also
284 * serve as EDMA event triggers.
287 static void gpio_irq_disable(struct irq_data *d)
289 struct davinci_gpio_regs __iomem *g = irq2regs(d);
290 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
292 writel_relaxed(mask, &g->clr_falling);
293 writel_relaxed(mask, &g->clr_rising);
296 static void gpio_irq_enable(struct irq_data *d)
298 struct davinci_gpio_regs __iomem *g = irq2regs(d);
299 uintptr_t mask = (uintptr_t)irq_data_get_irq_handler_data(d);
300 unsigned status = irqd_get_trigger_type(d);
302 status &= IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
304 status = IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING;
306 if (status & IRQ_TYPE_EDGE_FALLING)
307 writel_relaxed(mask, &g->set_falling);
308 if (status & IRQ_TYPE_EDGE_RISING)
309 writel_relaxed(mask, &g->set_rising);
312 static int gpio_irq_type(struct irq_data *d, unsigned trigger)
314 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
320 static struct irq_chip gpio_irqchip = {
322 .irq_enable = gpio_irq_enable,
323 .irq_disable = gpio_irq_disable,
324 .irq_set_type = gpio_irq_type,
325 .flags = IRQCHIP_SET_TYPE_MASKED | IRQCHIP_SKIP_SET_WAKE,
328 static void gpio_irq_handler(struct irq_desc *desc)
330 struct davinci_gpio_regs __iomem *g;
333 struct davinci_gpio_controller *d;
334 struct davinci_gpio_irq_data *irqdata;
336 irqdata = (struct davinci_gpio_irq_data *)irq_desc_get_handler_data(desc);
337 bank_num = irqdata->bank_num;
341 /* we only care about one bank */
342 if ((bank_num % 2) == 1)
345 /* temporarily mask (level sensitive) parent IRQ */
346 chained_irq_enter(irq_desc_get_chip(desc), desc);
350 irq_hw_number_t hw_irq;
353 status = readl_relaxed(&g->intstat) & mask;
356 writel_relaxed(status, &g->intstat);
358 /* now demux them to the right lowlevel handler */
363 /* Max number of gpios per controller is 144 so
364 * hw_irq will be in [0..143]
366 hw_irq = (bank_num / 2) * 32 + bit;
368 generic_handle_domain_irq(d->irq_domain, hw_irq);
371 chained_irq_exit(irq_desc_get_chip(desc), desc);
372 /* now it may re-trigger */
375 static int gpio_to_irq_banked(struct gpio_chip *chip, unsigned offset)
377 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
380 return irq_create_mapping(d->irq_domain, offset);
385 static int gpio_to_irq_unbanked(struct gpio_chip *chip, unsigned offset)
387 struct davinci_gpio_controller *d = gpiochip_get_data(chip);
390 * NOTE: we assume for now that only irqs in the first gpio_chip
391 * can provide direct-mapped IRQs to AINTC (up to 32 GPIOs).
393 if (offset < d->gpio_unbanked)
394 return d->irqs[offset];
399 static int gpio_irq_type_unbanked(struct irq_data *data, unsigned trigger)
401 struct davinci_gpio_controller *d;
402 struct davinci_gpio_regs __iomem *g;
405 d = (struct davinci_gpio_controller *)irq_data_get_irq_handler_data(data);
406 g = (struct davinci_gpio_regs __iomem *)d->regs[0];
407 for (i = 0; i < MAX_INT_PER_BANK; i++)
408 if (data->irq == d->irqs[i])
411 if (i == MAX_INT_PER_BANK)
414 mask = __gpio_mask(i);
416 if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
419 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
420 ? &g->set_falling : &g->clr_falling);
421 writel_relaxed(mask, (trigger & IRQ_TYPE_EDGE_RISING)
422 ? &g->set_rising : &g->clr_rising);
428 davinci_gpio_irq_map(struct irq_domain *d, unsigned int irq,
431 struct davinci_gpio_controller *chips =
432 (struct davinci_gpio_controller *)d->host_data;
433 struct davinci_gpio_regs __iomem *g = chips->regs[hw / 32];
435 irq_set_chip_and_handler_name(irq, &gpio_irqchip, handle_simple_irq,
437 irq_set_irq_type(irq, IRQ_TYPE_NONE);
438 irq_set_chip_data(irq, (__force void *)g);
439 irq_set_handler_data(irq, (void *)(uintptr_t)__gpio_mask(hw));
444 static const struct irq_domain_ops davinci_gpio_irq_ops = {
445 .map = davinci_gpio_irq_map,
446 .xlate = irq_domain_xlate_onetwocell,
449 static struct irq_chip *davinci_gpio_get_irq_chip(unsigned int irq)
451 static struct irq_chip_type gpio_unbanked;
453 gpio_unbanked = *irq_data_get_chip_type(irq_get_irq_data(irq));
455 return &gpio_unbanked.chip;
458 static struct irq_chip *keystone_gpio_get_irq_chip(unsigned int irq)
460 static struct irq_chip gpio_unbanked;
462 gpio_unbanked = *irq_get_chip(irq);
463 return &gpio_unbanked;
466 static const struct of_device_id davinci_gpio_ids[];
469 * NOTE: for suspend/resume, probably best to make a platform_device with
470 * suspend_late/resume_resume calls hooking into results of the set_wake()
471 * calls ... so if no gpios are wakeup events the clock can be disabled,
472 * with outputs left at previously set levels, and so that VDD3P3V.IOPWDN0
473 * (dm6446) can be set appropriately for GPIOV33 pins.
476 static int davinci_gpio_irq_setup(struct platform_device *pdev)
484 struct device *dev = &pdev->dev;
485 struct davinci_gpio_controller *chips = platform_get_drvdata(pdev);
486 struct davinci_gpio_platform_data *pdata = dev->platform_data;
487 struct davinci_gpio_regs __iomem *g;
488 struct irq_domain *irq_domain = NULL;
489 struct irq_chip *irq_chip;
490 struct davinci_gpio_irq_data *irqdata;
491 gpio_get_irq_chip_cb_t gpio_get_irq_chip;
494 * Use davinci_gpio_get_irq_chip by default to handle non DT cases
496 gpio_get_irq_chip = davinci_gpio_get_irq_chip;
498 gpio_get_irq_chip = (gpio_get_irq_chip_cb_t)device_get_match_data(dev);
500 ngpio = pdata->ngpio;
502 clk = devm_clk_get(dev, "gpio");
504 dev_err(dev, "Error %ld getting gpio clock\n", PTR_ERR(clk));
508 ret = clk_prepare_enable(clk);
512 if (!pdata->gpio_unbanked) {
513 irq = devm_irq_alloc_descs(dev, -1, 0, ngpio, 0);
515 dev_err(dev, "Couldn't allocate IRQ numbers\n");
516 clk_disable_unprepare(clk);
520 irq_domain = irq_domain_add_legacy(dev->of_node, ngpio, irq, 0,
521 &davinci_gpio_irq_ops,
524 dev_err(dev, "Couldn't register an IRQ domain\n");
525 clk_disable_unprepare(clk);
531 * Arrange gpiod_to_irq() support, handling either direct IRQs or
532 * banked IRQs. Having GPIOs in the first GPIO bank use direct
533 * IRQs, while the others use banked IRQs, would need some setup
534 * tweaks to recognize hardware which can do that.
536 chips->chip.to_irq = gpio_to_irq_banked;
537 chips->irq_domain = irq_domain;
540 * AINTC can handle direct/unbanked IRQs for GPIOs, with the GPIO
541 * controller only handling trigger modes. We currently assume no
542 * IRQ mux conflicts; gpio_irq_type_unbanked() is only for GPIOs.
544 if (pdata->gpio_unbanked) {
545 /* pass "bank 0" GPIO IRQs to AINTC */
546 chips->chip.to_irq = gpio_to_irq_unbanked;
547 chips->gpio_unbanked = pdata->gpio_unbanked;
548 binten = GENMASK(pdata->gpio_unbanked / 16, 0);
550 /* AINTC handles mask/unmask; GPIO handles triggering */
551 irq = chips->irqs[0];
552 irq_chip = gpio_get_irq_chip(irq);
553 irq_chip->name = "GPIO-AINTC";
554 irq_chip->irq_set_type = gpio_irq_type_unbanked;
556 /* default trigger: both edges */
558 writel_relaxed(~0, &g->set_falling);
559 writel_relaxed(~0, &g->set_rising);
561 /* set the direct IRQs up to use that irqchip */
562 for (gpio = 0; gpio < pdata->gpio_unbanked; gpio++) {
563 irq_set_chip(chips->irqs[gpio], irq_chip);
564 irq_set_handler_data(chips->irqs[gpio], chips);
565 irq_set_status_flags(chips->irqs[gpio],
573 * Or, AINTC can handle IRQs for banks of 16 GPIO IRQs, which we
574 * then chain through our own handler.
576 for (gpio = 0, bank = 0; gpio < ngpio; bank++, gpio += 16) {
577 /* disabled by default, enabled only as needed
578 * There are register sets for 32 GPIOs. 2 banks of 16
579 * GPIOs are covered by each set of registers hence divide by 2
581 g = chips->regs[bank / 2];
582 writel_relaxed(~0, &g->clr_falling);
583 writel_relaxed(~0, &g->clr_rising);
586 * Each chip handles 32 gpios, and each irq bank consists of 16
587 * gpio irqs. Pass the irq bank's corresponding controller to
588 * the chained irq handler.
590 irqdata = devm_kzalloc(&pdev->dev,
592 davinci_gpio_irq_data),
595 clk_disable_unprepare(clk);
600 irqdata->bank_num = bank;
601 irqdata->chip = chips;
603 irq_set_chained_handler_and_data(chips->irqs[bank],
604 gpio_irq_handler, irqdata);
611 * BINTEN -- per-bank interrupt enable. genirq would also let these
612 * bits be set/cleared dynamically.
614 writel_relaxed(binten, gpio_base + BINTEN);
619 static void davinci_gpio_save_context(struct davinci_gpio_controller *chips,
622 struct davinci_gpio_regs __iomem *g;
623 struct davinci_gpio_regs *context;
627 base = chips->regs[0] - offset_array[0];
628 chips->binten_context = readl_relaxed(base + BINTEN);
630 for (bank = 0; bank < nbank; bank++) {
631 g = chips->regs[bank];
632 context = &chips->context[bank];
633 context->dir = readl_relaxed(&g->dir);
634 context->set_data = readl_relaxed(&g->set_data);
635 context->set_rising = readl_relaxed(&g->set_rising);
636 context->set_falling = readl_relaxed(&g->set_falling);
639 /* Clear all interrupt status registers */
640 writel_relaxed(GENMASK(31, 0), &g->intstat);
643 static void davinci_gpio_restore_context(struct davinci_gpio_controller *chips,
646 struct davinci_gpio_regs __iomem *g;
647 struct davinci_gpio_regs *context;
651 base = chips->regs[0] - offset_array[0];
653 if (readl_relaxed(base + BINTEN) != chips->binten_context)
654 writel_relaxed(chips->binten_context, base + BINTEN);
656 for (bank = 0; bank < nbank; bank++) {
657 g = chips->regs[bank];
658 context = &chips->context[bank];
659 if (readl_relaxed(&g->dir) != context->dir)
660 writel_relaxed(context->dir, &g->dir);
661 if (readl_relaxed(&g->set_data) != context->set_data)
662 writel_relaxed(context->set_data, &g->set_data);
663 if (readl_relaxed(&g->set_rising) != context->set_rising)
664 writel_relaxed(context->set_rising, &g->set_rising);
665 if (readl_relaxed(&g->set_falling) != context->set_falling)
666 writel_relaxed(context->set_falling, &g->set_falling);
670 static int davinci_gpio_suspend(struct device *dev)
672 struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
673 struct davinci_gpio_platform_data *pdata = dev_get_platdata(dev);
674 u32 nbank = DIV_ROUND_UP(pdata->ngpio, 32);
676 davinci_gpio_save_context(chips, nbank);
681 static int davinci_gpio_resume(struct device *dev)
683 struct davinci_gpio_controller *chips = dev_get_drvdata(dev);
684 struct davinci_gpio_platform_data *pdata = dev_get_platdata(dev);
685 u32 nbank = DIV_ROUND_UP(pdata->ngpio, 32);
687 davinci_gpio_restore_context(chips, nbank);
692 static DEFINE_SIMPLE_DEV_PM_OPS(davinci_gpio_dev_pm_ops, davinci_gpio_suspend,
693 davinci_gpio_resume);
695 static const struct of_device_id davinci_gpio_ids[] = {
696 { .compatible = "ti,keystone-gpio", keystone_gpio_get_irq_chip},
697 { .compatible = "ti,am654-gpio", keystone_gpio_get_irq_chip},
698 { .compatible = "ti,dm6441-gpio", davinci_gpio_get_irq_chip},
701 MODULE_DEVICE_TABLE(of, davinci_gpio_ids);
703 static struct platform_driver davinci_gpio_driver = {
704 .probe = davinci_gpio_probe,
706 .name = "davinci_gpio",
707 .pm = pm_sleep_ptr(&davinci_gpio_dev_pm_ops),
708 .of_match_table = of_match_ptr(davinci_gpio_ids),
713 * GPIO driver registration needs to be done before machine_init functions
714 * access GPIO. Hence davinci_gpio_drv_reg() is a postcore_initcall.
716 static int __init davinci_gpio_drv_reg(void)
718 return platform_driver_register(&davinci_gpio_driver);
720 postcore_initcall(davinci_gpio_drv_reg);
722 static void __exit davinci_gpio_exit(void)
724 platform_driver_unregister(&davinci_gpio_driver);
726 module_exit(davinci_gpio_exit);
729 MODULE_DESCRIPTION("DAVINCI GPIO driver");
730 MODULE_LICENSE("GPL");
731 MODULE_ALIAS("platform:gpio-davinci");