1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * GPIO Testing Device Driver
6  * Copyright (C) 2015-2016  Bamvor Jian Zhang <bamv2005@gmail.com>
13 #include <linux/gpio/driver.h>
30  * We're storing two values per chip: the GPIO base and the number
31  * of GPIO lines.
38  * struct gpio_pin_status - structure describing a GPIO status
39  * @dir:       Configures direction of gpio as "in" or "out"
40  * @value:     Configures status of the gpio as 0(low) or 1(high)
50 	struct gpio_mockup_line_status *lines;  member
85 	return chip->lines[offset].value;  in __gpio_mockup_get()
93 	mutex_lock(&chip->lock);  in gpio_mockup_get()
95 	mutex_unlock(&chip->lock);  in gpio_mockup_get()
106 	mutex_lock(&chip->lock);  in gpio_mockup_get_multiple()
107 	for_each_set_bit(bit, mask, gc->ngpio) {  in gpio_mockup_get_multiple()
111 	mutex_unlock(&chip->lock);  in gpio_mockup_get_multiple()
119 	chip->lines[offset].value = !!value;  in __gpio_mockup_set()
127 	mutex_lock(&chip->lock);  in gpio_mockup_set()
129 	mutex_unlock(&chip->lock);  in gpio_mockup_set()
138 	mutex_lock(&chip->lock);  in gpio_mockup_set_multiple()
139 	for_each_set_bit(bit, mask, gc->ngpio)  in gpio_mockup_set_multiple()
141 	mutex_unlock(&chip->lock);  in gpio_mockup_set_multiple()
147 	struct gpio_chip *gc = &chip->gc;  in gpio_mockup_apply_pull()
151 	mutex_lock(&chip->lock);  in gpio_mockup_apply_pull()
153 	if (test_bit(FLAG_REQUESTED, &desc->flags) &&  in gpio_mockup_apply_pull()
154 	    !test_bit(FLAG_IS_OUT, &desc->flags)) {  in gpio_mockup_apply_pull()
159 		irq = irq_find_mapping(chip->irq_sim_domain, offset);  in gpio_mockup_apply_pull()
162 			 * This is fine - it just means, nobody is listening  in gpio_mockup_apply_pull()
182 	if (!test_bit(FLAG_REQUESTED, &desc->flags) ||  in gpio_mockup_apply_pull()
183 	    !test_bit(FLAG_IS_OUT, &desc->flags))  in gpio_mockup_apply_pull()
187 	chip->lines[offset].pull = value;  in gpio_mockup_apply_pull()
188 	mutex_unlock(&chip->lock);  in gpio_mockup_apply_pull()
205 	return -ENOTSUPP;  in gpio_mockup_set_config()
213 	mutex_lock(&chip->lock);  in gpio_mockup_dirout()
214 	chip->lines[offset].dir = GPIO_LINE_DIRECTION_OUT;  in gpio_mockup_dirout()
216 	mutex_unlock(&chip->lock);  in gpio_mockup_dirout()
225 	mutex_lock(&chip->lock);  in gpio_mockup_dirin()
226 	chip->lines[offset].dir = GPIO_LINE_DIRECTION_IN;  in gpio_mockup_dirin()
227 	mutex_unlock(&chip->lock);  in gpio_mockup_dirin()
237 	mutex_lock(&chip->lock);  in gpio_mockup_get_direction()
238 	direction = chip->lines[offset].dir;  in gpio_mockup_get_direction()
239 	mutex_unlock(&chip->lock);  in gpio_mockup_get_direction()
248 	return irq_create_mapping(chip->irq_sim_domain, offset);  in gpio_mockup_to_irq()
255 	__gpio_mockup_set(chip, offset, chip->lines[offset].pull);  in gpio_mockup_free()
272 	sfile = file->private_data;  in gpio_mockup_debugfs_read()
273 	priv = sfile->private;  in gpio_mockup_debugfs_read()
274 	chip = priv->chip;  in gpio_mockup_debugfs_read()
275 	gc = &chip->gc;  in gpio_mockup_debugfs_read()
277 	val = gpio_mockup_get(gc, priv->offset);  in gpio_mockup_debugfs_read()
292 		return -EINVAL;  in gpio_mockup_debugfs_write()
298 		return -EINVAL;  in gpio_mockup_debugfs_write()
300 	sfile = file->private_data;  in gpio_mockup_debugfs_write()
301 	priv = sfile->private;  in gpio_mockup_debugfs_write()
302 	rv = gpio_mockup_apply_pull(priv->chip, priv->offset, val);  in gpio_mockup_debugfs_write()
311 	return single_open(file, NULL, inode->i_private);  in gpio_mockup_debugfs_open()
316  * name under /sys/kernel/debug/gpio-mockup/. Each line is represented by
320  * line's file changes the current *pull*. Default pull for mockup lines is
324  * - when a line pulled down is requested in output mode and driven high, its
326  * - when the line is requested in output mode and driven high, writing 0 to
329  * - line requested in input mode always reports the same value as its pull
331  * - when the line is requested in input mode and monitored for events, writing
353 	gc = &chip->gc;  in gpio_mockup_debugfs_setup()
354 	devname = dev_name(&gc->gpiodev->dev);  in gpio_mockup_debugfs_setup()
356 	chip->dbg_dir = debugfs_create_dir(devname, gpio_mockup_dbg_dir);  in gpio_mockup_debugfs_setup()
358 	for (i = 0; i < gc->ngpio; i++) {  in gpio_mockup_debugfs_setup()
367 		priv->chip = chip;  in gpio_mockup_debugfs_setup()
368 		priv->offset = i;  in gpio_mockup_debugfs_setup()
369 		priv->desc = gpiochip_get_desc(gc, i);  in gpio_mockup_debugfs_setup()
371 		debugfs_create_file(name, 0200, chip->dbg_dir, priv,  in gpio_mockup_debugfs_setup()
380 	debugfs_remove_recursive(chip->dbg_dir);  in gpio_mockup_debugfs_cleanup()
386 	struct gpio_chip *gc = &chip->gc;  in gpio_mockup_dispose_mappings()
389 	for (i = 0; i < gc->ngpio; i++) {  in gpio_mockup_dispose_mappings()
390 		irq = irq_find_mapping(chip->irq_sim_domain, i);  in gpio_mockup_dispose_mappings()
405 	dev = &pdev->dev;  in gpio_mockup_probe()
407 	rv = device_property_read_u32(dev, "gpio-base", &base);  in gpio_mockup_probe()
409 		base = -1;  in gpio_mockup_probe()
411 	rv = device_property_read_u16(dev, "nr-gpios", &ngpio);  in gpio_mockup_probe()
415 	rv = device_property_read_string(dev, "chip-label", &name);  in gpio_mockup_probe()
421 		return -ENOMEM;  in gpio_mockup_probe()
423 	mutex_init(&chip->lock);  in gpio_mockup_probe()
425 	gc = &chip->gc;  in gpio_mockup_probe()
426 	gc->base = base;  in gpio_mockup_probe()
427 	gc->ngpio = ngpio;  in gpio_mockup_probe()
428 	gc->label = name;  in gpio_mockup_probe()
429 	gc->owner = THIS_MODULE;  in gpio_mockup_probe()
430 	gc->parent = dev;  in gpio_mockup_probe()
431 	gc->get = gpio_mockup_get;  in gpio_mockup_probe()
432 	gc->set = gpio_mockup_set;  in gpio_mockup_probe()
433 	gc->get_multiple = gpio_mockup_get_multiple;  in gpio_mockup_probe()
434 	gc->set_multiple = gpio_mockup_set_multiple;  in gpio_mockup_probe()
435 	gc->direction_output = gpio_mockup_dirout;  in gpio_mockup_probe()
436 	gc->direction_input = gpio_mockup_dirin;  in gpio_mockup_probe()
437 	gc->get_direction = gpio_mockup_get_direction;  in gpio_mockup_probe()
438 	gc->set_config = gpio_mockup_set_config;  in gpio_mockup_probe()
439 	gc->to_irq = gpio_mockup_to_irq;  in gpio_mockup_probe()
440 	gc->free = gpio_mockup_free;  in gpio_mockup_probe()
442 	chip->lines = devm_kcalloc(dev, gc->ngpio,  in gpio_mockup_probe()
443 				   sizeof(*chip->lines), GFP_KERNEL);  in gpio_mockup_probe()
444 	if (!chip->lines)  in gpio_mockup_probe()
445 		return -ENOMEM;  in gpio_mockup_probe()
447 	for (i = 0; i < gc->ngpio; i++)  in gpio_mockup_probe()
448 		chip->lines[i].dir = GPIO_LINE_DIRECTION_IN;  in gpio_mockup_probe()
450 	chip->irq_sim_domain = devm_irq_domain_create_sim(dev, NULL,  in gpio_mockup_probe()
451 							  gc->ngpio);  in gpio_mockup_probe()
452 	if (IS_ERR(chip->irq_sim_domain))  in gpio_mockup_probe()
453 		return PTR_ERR(chip->irq_sim_domain);  in gpio_mockup_probe()
459 	rv = devm_gpiochip_add_data(dev, &chip->gc, chip);  in gpio_mockup_probe()
469 	{ .compatible = "gpio-mockup", },
476 		.name = "gpio-mockup",
495 		fwnode = dev_fwnode(&pdev->dev);  in gpio_mockup_unregister_pdevs()
515 	snprintf(chip_label, sizeof(chip_label), "gpio-mockup-%c", idx + 'A');  in gpio_mockup_register_chip()
516 	properties[prop++] = PROPERTY_ENTRY_STRING("chip-label", chip_label);  in gpio_mockup_register_chip()
520 		properties[prop++] = PROPERTY_ENTRY_U32("gpio-base", base);  in gpio_mockup_register_chip()
523 			 : gpio_mockup_range_ngpio(idx) - base;  in gpio_mockup_register_chip()
524 	properties[prop++] = PROPERTY_ENTRY_U16("nr-gpios", ngpio);  in gpio_mockup_register_chip()
529 			return -ENOMEM;  in gpio_mockup_register_chip()
532 					"gpio-line-names", line_names, ngpio);  in gpio_mockup_register_chip()
541 	pdevinfo.name = "gpio-mockup";  in gpio_mockup_register_chip()
564 		return -EINVAL;  in gpio_mockup_init()
570 	 * The second value in the <base GPIO - number of GPIOS> pair must  in gpio_mockup_init()
575 			return -EINVAL;  in gpio_mockup_init()
578 	gpio_mockup_dbg_dir = debugfs_create_dir("gpio-mockup", NULL);  in gpio_mockup_init()
613 MODULE_DESCRIPTION("GPIO Testing driver");