Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 9202ba23 authored by Bartosz Golaszewski's avatar Bartosz Golaszewski Committed by Linus Walleij
Browse files

gpio: mockup: implement event injecting over debugfs 



Create a debugfs directory for every mockup chip and a single file
for every line. Writing (0 or 1) to these files allows the user to
inject line events (falling or rising edge respectively).

Signed-off-by: default avatarBartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent e2ff7408

drivers/gpio/gpio-mockup.c

+115 −1
Original line number Diff line number Diff line
@@ -14,11 +14,16 @@ 
#include <linux/init.h>

#include <linux/module.h>

#include <linux/gpio/driver.h>

#include <linux/gpio/consumer.h>

#include <linux/platform_device.h>

#include <linux/slab.h>

#include <linux/interrupt.h>

#include <linux/irq.h>

#include <linux/irq_work.h>

#include <linux/debugfs.h>

#include <linux/uaccess.h>



#include "gpiolib.h"



#define GPIO_MOCKUP_NAME	"gpio-mockup"

#define	GPIO_MOCKUP_MAX_GC	10
@@ -47,6 +52,13 @@ struct gpio_mockup_chip { 
	struct gpio_chip gc;

	struct gpio_mockup_line_status *lines;

	struct gpio_mockup_irq_context irq_ctx;

	struct dentry *dbg_dir;

};



struct gpio_mockup_dbgfs_private {

	struct gpio_mockup_chip *chip;

	struct gpio_desc *desc;

	int offset;

};



static int gpio_mockup_ranges[GPIO_MOCKUP_MAX_GC << 1];
@@ -58,6 +70,7 @@ module_param_named(gpio_mockup_named_lines, 
		   gpio_mockup_named_lines, bool, 0400);



static const char gpio_mockup_name_start = 'A';

static struct dentry *gpio_mockup_dbg_dir;



static int gpio_mockup_get(struct gpio_chip *gc, unsigned int offset)

{
@@ -175,6 +188,94 @@ static int gpio_mockup_irqchip_setup(struct device *dev, 
	return 0;

}



static ssize_t gpio_mockup_event_write(struct file *file,

				       const char __user *usr_buf,

				       size_t size, loff_t *ppos)

{

	struct gpio_mockup_dbgfs_private *priv;

	struct gpio_mockup_chip *chip;

	struct seq_file *sfile;

	struct gpio_desc *desc;

	struct gpio_chip *gc;

	int status, val;

	char buf;



	sfile = file->private_data;

	priv = sfile->private;

	desc = priv->desc;

	chip = priv->chip;

	gc = &chip->gc;



	status = copy_from_user(&buf, usr_buf, 1);

	if (status)

		return status;



	if (buf == '0')

		val = 0;

	else if (buf == '1')

		val = 1;

	else

		return -EINVAL;



	gpiod_set_value_cansleep(desc, val);

	priv->chip->irq_ctx.irq = gc->irq_base + priv->offset;

	irq_work_queue(&priv->chip->irq_ctx.work);



	return size;

}



static int gpio_mockup_event_open(struct inode *inode, struct file *file)

{

	return single_open(file, NULL, inode->i_private);

}



static const struct file_operations gpio_mockup_event_ops = {

	.owner = THIS_MODULE,

	.open = gpio_mockup_event_open,

	.write = gpio_mockup_event_write,

	.llseek = no_llseek,

};



static void gpio_mockup_debugfs_setup(struct device *dev,

				      struct gpio_mockup_chip *chip)

{

	struct gpio_mockup_dbgfs_private *priv;

	struct dentry *evfile;

	struct gpio_chip *gc;

	char *name;

	int i;



	gc = &chip->gc;



	chip->dbg_dir = debugfs_create_dir(gc->label, gpio_mockup_dbg_dir);

	if (!chip->dbg_dir)

		goto err;



	for (i = 0; i < gc->ngpio; i++) {

		name = devm_kasprintf(dev, GFP_KERNEL, "%d", i);

		if (!name)

			goto err;



		priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);

		if (!priv)

			goto err;



		priv->chip = chip;

		priv->offset = i;

		priv->desc = &gc->gpiodev->descs[i];



		evfile = debugfs_create_file(name, 0200, chip->dbg_dir, priv,

					     &gpio_mockup_event_ops);

		if (!evfile)

			goto err;

	}



	return;



err:

	dev_err(dev, "error creating debugfs directory\n");

}



static int gpio_mockup_add(struct device *dev,

			   struct gpio_mockup_chip *chip,

			   const char *name, int base, int ngpio)
@@ -209,7 +310,14 @@ static int gpio_mockup_add(struct device *dev, 
	if (ret)

		return ret;



	return devm_gpiochip_add_data(dev, &chip->gc, chip);

	ret = devm_gpiochip_add_data(dev, &chip->gc, chip);

	if (ret)

		return ret;



	if (gpio_mockup_dbg_dir)

		gpio_mockup_debugfs_setup(dev, chip);



	return 0;

}



static int gpio_mockup_probe(struct platform_device *pdev)
@@ -291,6 +399,11 @@ static int __init mock_device_init(void) 
{

	int err;



	gpio_mockup_dbg_dir = debugfs_create_dir("gpio-mockup-event", NULL);

	if (!gpio_mockup_dbg_dir)

		pr_err("%s: error creating debugfs directory\n",

		       GPIO_MOCKUP_NAME);



	pdev = platform_device_alloc(GPIO_MOCKUP_NAME, -1);

	if (!pdev)

		return -ENOMEM;
@@ -312,6 +425,7 @@ static int __init mock_device_init(void) 


static void __exit mock_device_exit(void)

{

	debugfs_remove_recursive(gpio_mockup_dbg_dir);

	platform_driver_unregister(&gpio_mockup_driver);

	platform_device_unregister(pdev);

}