@@ -19,6 +19,10 @@
#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 +51,13 @@ 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 +69,7 @@ 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 +187,94 @@ 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 +309,14 @@ 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)
@@ -277,6 +384,11 @@ 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;
@@ -298,6 +410,7 @@ 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);
}
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: Bartosz Golaszewski <bgolaszewski@baylibre.com> --- drivers/gpio/gpio-mockup.c | 115 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 114 insertions(+), 1 deletion(-)