1 // SPDX-License-Identifier: GPL-2.0+
3  * OF helpers for the GPIO API
5  * Copyright (c) 2007-2008  MontaVista Software, Inc.
15 #include <linux/gpio/consumer.h>
21 #include <linux/gpio/machine.h>
24 #include "gpiolib-of.h"
27  * of_gpio_spi_cs_get_count() - special GPIO counting for SPI
29  * @con_id: Function within the GPIO consumer
31  * Some elder GPIO controllers need special quirks. Currently we handle
32  * the Freescale and PPC GPIO controller with bindings that doesn't use the
33  * established "cs-gpios" for chip selects but instead rely on
35  * the counting of "cs-gpios" to count "gpios" transparent to the
40 	struct device_node *np = dev->of_node;  in of_gpio_spi_cs_get_count()
48 	    !of_device_is_compatible(np, "ibm,ppc4xx-spi"))  in of_gpio_spi_cs_get_count()
56  * FIXME: get rid of those external users by converting them to GPIO
71 			snprintf(propname, sizeof(propname), "%s-%s",  in of_gpio_get_count()
77 		ret = of_gpio_named_count(dev->of_node, propname);  in of_gpio_get_count()
81 	return ret ? ret : -ENOENT;  in of_gpio_get_count()
88 	return chip->gpiodev->dev.of_node == gpiospec->np &&  in of_gpiochip_match_node_and_xlate()
89 				chip->of_xlate &&  in of_gpiochip_match_node_and_xlate()
90 				chip->of_xlate(chip, gpiospec, NULL) >= 0;  in of_gpiochip_match_node_and_xlate()
105 	if (chip->of_gpio_n_cells != gpiospec->args_count)  in of_xlate_and_get_gpiod_flags()
106 		return ERR_PTR(-EINVAL);  in of_xlate_and_get_gpiod_flags()
108 	ret = chip->of_xlate(chip, gpiospec, flags);  in of_xlate_and_get_gpiod_flags()
116  * of_gpio_need_valid_mask() - figure out if the OF GPIO driver needs
125 	struct device_node *np = gc->of_node;  in of_gpio_need_valid_mask()
127 	size = of_property_count_u32_elems(np,  "gpio-reserved-ranges");  in of_gpio_need_valid_mask()
139 	 * Some GPIO fixed regulator quirks.  in of_gpio_flags_quirks()
143 	    (of_device_is_compatible(np, "regulator-fixed") ||  in of_gpio_flags_quirks()
144 	     of_device_is_compatible(np, "reg-fixed-voltage") ||  in of_gpio_flags_quirks()
145 	     (!(strcmp(propname, "enable-gpio") &&  in of_gpio_flags_quirks()
146 		strcmp(propname, "enable-gpios")) &&  in of_gpio_flags_quirks()
147 	      of_device_is_compatible(np, "regulator-gpio")))) {  in of_gpio_flags_quirks()
149 							 "enable-active-high");  in of_gpio_flags_quirks()
151 		 * The regulator GPIO handles are specified such that the  in of_gpio_flags_quirks()
152 		 * presence or absence of "enable-active-high" solely controls  in of_gpio_flags_quirks()
153 		 * the polarity of the GPIO line. Any phandle flags must  in of_gpio_flags_quirks()
157 			pr_warn("%s GPIO handle specifies active low - ignored\n",  in of_gpio_flags_quirks()
168 	    of_device_is_compatible(np, "reg-fixed-voltage") &&  in of_gpio_flags_quirks()
169 	    of_property_read_bool(np, "gpio-open-drain")) {  in of_gpio_flags_quirks()
171 		pr_info("%s uses legacy open drain flag - update the DTS if you can\n",  in of_gpio_flags_quirks()
177 	 * property named "cs-gpios" we need to inspect the child node  in of_gpio_flags_quirks()
180 	if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&  in of_gpio_flags_quirks()
181 	    of_property_read_bool(np, "cs-gpios")) {  in of_gpio_flags_quirks()
194 				 * by just omitting "spi-cs-high" in the  in of_gpio_flags_quirks()
199 				 * and has the "spi-cs-high" set, we get a  in of_gpio_flags_quirks()
200 				 * conflict and the "spi-cs-high" flag will  in of_gpio_flags_quirks()
203 				if (of_property_read_bool(child, "spi-cs-high")) {  in of_gpio_flags_quirks()
205 						pr_warn("%s GPIO handle specifies active low - ignored\n",  in of_gpio_flags_quirks()
221 	/* Legacy handling of stmmac's active-low PHY reset line */  in of_gpio_flags_quirks()
223 	    !strcmp(propname, "snps,reset-gpio") &&  in of_gpio_flags_quirks()
224 	    of_property_read_bool(np, "snps,reset-active-low"))  in of_gpio_flags_quirks()
229  * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
230  * @np:		device node to get GPIO from
231  * @propname:	property name containing gpio specifier(s)
232  * @index:	index of the GPIO
235  * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
237  * in flags for the GPIO.
247 	ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,  in of_get_named_gpiod_flags()
257 		desc = ERR_PTR(-EPROBE_DEFER);  in of_get_named_gpiod_flags()
268 	pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",  in of_get_named_gpiod_flags()
293  * gpiod_get_from_of_node() - obtain a GPIO from an OF node
295  * @propname:	name of the DT property representing the GPIO
296  * @index:	index of the GPIO to obtain for the consumer
297  * @dflags:	GPIO initialization flags
298  * @label:	label to attach to the requested GPIO
301  * On successful request the GPIO pin is configured in accordance with
333 	if (ret == -EBUSY && (dflags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))  in gpiod_get_from_of_node()
368  * The SPI GPIO bindings happened before we managed to establish that GPIO
369  * properties should be named "foo-gpios" so we have this special kludge for
376 	struct device_node *np = dev->of_node;  in of_find_spi_gpio()
384 		return ERR_PTR(-ENOENT);  in of_find_spi_gpio()
386 	/* Allow this specifically for "spi-gpio" devices */  in of_find_spi_gpio()
387 	if (!of_device_is_compatible(np, "spi-gpio") || !con_id)  in of_find_spi_gpio()
388 		return ERR_PTR(-ENOENT);  in of_find_spi_gpio()
390 	/* Will be "gpio-sck", "gpio-mosi" or "gpio-miso" */  in of_find_spi_gpio()
391 	snprintf(prop_name, sizeof(prop_name), "%s-%s", "gpio", con_id);  in of_find_spi_gpio()
399  * lines rather than "cs-gpios" like all other SPI hardware. Account for this
407 	struct device_node *np = dev->of_node;  in of_find_spi_cs_gpio()
410 		return ERR_PTR(-ENOENT);  in of_find_spi_cs_gpio()
415 	    !of_device_is_compatible(np, "ibm,ppc4xx-spi"))  in of_find_spi_cs_gpio()
416 		return ERR_PTR(-ENOENT);  in of_find_spi_cs_gpio()
417 	/* Allow only if asking for "cs-gpios" */  in of_find_spi_cs_gpio()
419 		return ERR_PTR(-ENOENT);  in of_find_spi_cs_gpio()
422 	 * While all other SPI controllers use "cs-gpios" the Freescale  in of_find_spi_cs_gpio()
423 	 * uses just "gpios" so translate to that when "cs-gpios" is  in of_find_spi_cs_gpio()
430  * Some regulator bindings happened before we managed to establish that GPIO
431  * properties should be named "foo-gpios" so we have this special kludge for
437 	/* These are the connection IDs we accept as legacy GPIO phandles */  in of_find_regulator_gpio()
443 	struct device_node *np = dev->of_node;  in of_find_regulator_gpio()
448 		return ERR_PTR(-ENOENT);  in of_find_regulator_gpio()
451 		return ERR_PTR(-ENOENT);  in of_find_regulator_gpio()
455 		return ERR_PTR(-ENOENT);  in of_find_regulator_gpio()
466 		return ERR_PTR(-ENOENT);  in of_find_arizona_gpio()
469 		return ERR_PTR(-ENOENT);  in of_find_arizona_gpio()
471 	return of_get_named_gpiod_flags(dev->of_node, con_id, 0, of_flags);  in of_find_arizona_gpio()
480 	 * an undocumented DT GPIO line named "fcs,int_n" without the compulsory "-gpios"  in of_find_usb_gpio()
484 		return ERR_PTR(-ENOENT);  in of_find_usb_gpio()
487 		return ERR_PTR(-ENOENT);  in of_find_usb_gpio()
489 	return of_get_named_gpiod_flags(dev->of_node, con_id, 0, of_flags);  in of_find_usb_gpio()
500 	/* Try GPIO property "foo-gpios" and "foo-gpio" */  in of_find_gpio()
503 			snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id,  in of_find_gpio()
509 		desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,  in of_find_gpio()
512 		if (!IS_ERR(desc) || PTR_ERR(desc) != -ENOENT)  in of_find_gpio()
516 	if (PTR_ERR(desc) == -ENOENT) {  in of_find_gpio()
521 	if (PTR_ERR(desc) == -ENOENT) {  in of_find_gpio()
528 	if (PTR_ERR(desc) == -ENOENT) {  in of_find_gpio()
533 	if (PTR_ERR(desc) == -ENOENT)  in of_find_gpio()
536 	if (PTR_ERR(desc) == -ENOENT)  in of_find_gpio()
564  * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API
565  * @np:		device node to get GPIO from
566  * @chip:	GPIO chip whose hog is parsed
567  * @idx:	Index of the GPIO to parse
568  * @name:	GPIO line name
569  * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from
571  * @dflags:	gpiod_flags - optional GPIO initialization flags
573  * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
590 	chip_np = chip->of_node;  in of_parse_own_gpio()
592 		return ERR_PTR(-EINVAL);  in of_parse_own_gpio()
598 	ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);  in of_parse_own_gpio()
627 	else if (of_property_read_bool(np, "output-low"))  in of_parse_own_gpio()
629 	else if (of_property_read_bool(np, "output-high"))  in of_parse_own_gpio()
632 		pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n",  in of_parse_own_gpio()
634 		return ERR_PTR(-EINVAL);  in of_parse_own_gpio()
637 	if (name && of_property_read_string(np, "line-name", name))  in of_parse_own_gpio()
638 		*name = np->name;  in of_parse_own_gpio()
644  * of_gpiochip_add_hog - Add all hogs in a hog device node
645  * @chip:	gpio chip to act on
646  * @hog:	device node describing the hogs
650 static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog)  in of_gpiochip_add_hog()  argument
660 		desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags);  in of_gpiochip_add_hog()
669 		desc->hog = hog;  in of_gpiochip_add_hog()
677  * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
678  * @chip:	gpio chip to act on
680  * This is only used by of_gpiochip_add to request/set GPIO initial
689 	for_each_available_child_of_node(chip->of_node, np) {  in of_gpiochip_scan_gpios()
690 		if (!of_property_read_bool(np, "gpio-hog"))  in of_gpiochip_scan_gpios()
707  * of_gpiochip_remove_hog - Remove all hogs in a hog device node
708  * @chip:	gpio chip to act on
709  * @hog:	device node describing the hogs
712 				   struct device_node *hog)  in of_gpiochip_remove_hog()  argument
714 	struct gpio_desc *descs = chip->gpiodev->descs;  in of_gpiochip_remove_hog()
717 	for (i = 0; i < chip->ngpio; i++) {  in of_gpiochip_remove_hog()
719 		    descs[i].hog == hog)  in of_gpiochip_remove_hog()
726 	return chip->gpiodev->dev.of_node == data;  in of_gpiochip_match_node()
742 	 * This only supports adding and removing complete gpio-hog nodes.  in of_gpio_notify()
743 	 * Modifying an existing gpio-hog node is not supported (except for  in of_gpio_notify()
749 		if (!of_property_read_bool(rd->dn, "gpio-hog"))  in of_gpio_notify()
752 		if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))  in of_gpio_notify()
755 		chip = of_find_gpiochip_by_node(rd->dn->parent);  in of_gpio_notify()
759 		ret = of_gpiochip_add_hog(chip, rd->dn);  in of_gpio_notify()
762 			       rd->dn);  in of_gpio_notify()
763 			of_node_clear_flag(rd->dn, OF_POPULATED);  in of_gpio_notify()
769 		if (!of_node_check_flag(rd->dn, OF_POPULATED))  in of_gpio_notify()
772 		chip = of_find_gpiochip_by_node(rd->dn->parent);  in of_gpio_notify()
776 		of_gpiochip_remove_hog(chip, rd->dn);  in of_gpio_notify()
777 		of_node_clear_flag(rd->dn, OF_POPULATED);  in of_gpio_notify()
790  * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags
792  * @gpiospec:	GPIO specifier as found in the device tree
796  * GPIO chips. This function performs only one sanity check: whether GPIO
805 	 * write your own xlate function (that will have to retrieve the GPIO  in of_gpio_simple_xlate()
806 	 * number and the flags from a single gpio cell -- this is possible,  in of_gpio_simple_xlate()
809 	if (gc->of_gpio_n_cells < 2) {  in of_gpio_simple_xlate()
811 		return -EINVAL;  in of_gpio_simple_xlate()
814 	if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))  in of_gpio_simple_xlate()
815 		return -EINVAL;  in of_gpio_simple_xlate()
817 	if (gpiospec->args[0] >= gc->ngpio)  in of_gpio_simple_xlate()
818 		return -EINVAL;  in of_gpio_simple_xlate()
821 		*flags = gpiospec->args[1];  in of_gpio_simple_xlate()
823 	return gpiospec->args[0];  in of_gpio_simple_xlate()
827  * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
828  * @np:		device node of the GPIO chip
835  *    - all the callbacks
836  *    - of_gpio_n_cells
837  *    - of_xlate callback (optional)
840  *    - save_regs callback (optional)
850 	int ret = -ENOMEM;  in of_mm_gpiochip_add_data()
851 	struct gpio_chip *gc = &mm_gc->gc;  in of_mm_gpiochip_add_data()
853 	gc->label = kasprintf(GFP_KERNEL, "%pOF", np);  in of_mm_gpiochip_add_data()
854 	if (!gc->label)  in of_mm_gpiochip_add_data()
857 	mm_gc->regs = of_iomap(np, 0);  in of_mm_gpiochip_add_data()
858 	if (!mm_gc->regs)  in of_mm_gpiochip_add_data()
861 	gc->base = -1;  in of_mm_gpiochip_add_data()
863 	if (mm_gc->save_regs)  in of_mm_gpiochip_add_data()
864 		mm_gc->save_regs(mm_gc);  in of_mm_gpiochip_add_data()
866 	mm_gc->gc.of_node = np;  in of_mm_gpiochip_add_data()
874 	iounmap(mm_gc->regs);  in of_mm_gpiochip_add_data()
876 	kfree(gc->label);  in of_mm_gpiochip_add_data()
878 	pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);  in of_mm_gpiochip_add_data()
884  * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)
889 	struct gpio_chip *gc = &mm_gc->gc;  in of_mm_gpiochip_remove()
895 	iounmap(mm_gc->regs);  in of_mm_gpiochip_remove()
896 	kfree(gc->label);  in of_mm_gpiochip_remove()
904 	struct device_node *np = chip->of_node;  in of_gpiochip_init_valid_mask()
906 	len = of_property_count_u32_elems(np,  "gpio-reserved-ranges");  in of_gpiochip_init_valid_mask()
911 		of_property_read_u32_index(np, "gpio-reserved-ranges",  in of_gpiochip_init_valid_mask()
913 		of_property_read_u32_index(np, "gpio-reserved-ranges",  in of_gpiochip_init_valid_mask()
915 		if (start >= chip->ngpio || start + count >= chip->ngpio)  in of_gpiochip_init_valid_mask()
918 		bitmap_clear(chip->valid_mask, start, count);  in of_gpiochip_init_valid_mask()
925 	struct device_node *np = chip->of_node;  in of_gpiochip_add_pin_range()
930 	static const char group_names_propname[] = "gpio-ranges-group-names";  in of_gpiochip_add_pin_range()
939 		ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,  in of_gpiochip_add_pin_range()
947 			return -EPROBE_DEFER;  in of_gpiochip_add_pin_range()
955 					pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",  in of_gpiochip_add_pin_range()
971 				pr_err("%pOF: Illegal gpio-range format.\n",  in of_gpiochip_add_pin_range()
977 				pr_err("%pOF: GPIO group range requested but no %s property.\n",  in of_gpiochip_add_pin_range()
989 				pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",  in of_gpiochip_add_pin_range()
1012 	if (!chip->of_node)  in of_gpiochip_add()
1015 	if (!chip->of_xlate) {  in of_gpiochip_add()
1016 		chip->of_gpio_n_cells = 2;  in of_gpiochip_add()
1017 		chip->of_xlate = of_gpio_simple_xlate;  in of_gpiochip_add()
1020 	if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)  in of_gpiochip_add()
1021 		return -EINVAL;  in of_gpiochip_add()
1029 	of_node_get(chip->of_node);  in of_gpiochip_add()
1033 		of_node_put(chip->of_node);  in of_gpiochip_add()
1040 	of_node_put(chip->of_node);  in of_gpiochip_remove()