[PATCH v3 3/3] gpio: virtuser: convert to use dev-sync-probe utilities

From: Koichiro Den
Date: Fri Feb 21 2025 - 08:38:21 EST


Update gpio-virtuser to use the new dev-sync-probe helper functions for
synchronized platform device creation, reducing code duplication.

No functional change.

Signed-off-by: Koichiro Den <koichiro.den@xxxxxxxxxxxxx>
---
drivers/gpio/Kconfig | 1 +
drivers/gpio/gpio-virtuser.c | 73 +++++-------------------------------
2 files changed, 11 insertions(+), 63 deletions(-)

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 297ad8f78f38..59c48c632197 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1938,6 +1938,7 @@ config GPIO_VIRTUSER
select DEBUG_FS
select CONFIGFS_FS
select IRQ_WORK
+ select DEV_SYNC_PROBE
help
Say Y here to enable the configurable, configfs-based virtual GPIO
consumer testing driver.
diff --git a/drivers/gpio/gpio-virtuser.c b/drivers/gpio/gpio-virtuser.c
index e89f299f2140..13407fd4f0eb 100644
--- a/drivers/gpio/gpio-virtuser.c
+++ b/drivers/gpio/gpio-virtuser.c
@@ -11,7 +11,6 @@
#include <linux/atomic.h>
#include <linux/bitmap.h>
#include <linux/cleanup.h>
-#include <linux/completion.h>
#include <linux/configfs.h>
#include <linux/debugfs.h>
#include <linux/device.h>
@@ -37,6 +36,8 @@
#include <linux/string_helpers.h>
#include <linux/types.h>

+#include "dev-sync-probe.h"
+
#define GPIO_VIRTUSER_NAME_BUF_LEN 32

static DEFINE_IDA(gpio_virtuser_ida);
@@ -973,49 +974,17 @@ static struct platform_driver gpio_virtuser_driver = {
};

struct gpio_virtuser_device {
+ struct dev_sync_probe_data probe_data;
struct config_group group;

- struct platform_device *pdev;
int id;
struct mutex lock;

- struct notifier_block bus_notifier;
- struct completion probe_completion;
- bool driver_bound;
-
struct gpiod_lookup_table *lookup_table;

struct list_head lookup_list;
};

-static int gpio_virtuser_bus_notifier_call(struct notifier_block *nb,
- unsigned long action, void *data)
-{
- struct gpio_virtuser_device *vdev;
- struct device *dev = data;
- char devname[32];
-
- vdev = container_of(nb, struct gpio_virtuser_device, bus_notifier);
- snprintf(devname, sizeof(devname), "gpio-virtuser.%d", vdev->id);
-
- if (!device_match_name(dev, devname))
- return NOTIFY_DONE;
-
- switch (action) {
- case BUS_NOTIFY_BOUND_DRIVER:
- vdev->driver_bound = true;
- break;
- case BUS_NOTIFY_DRIVER_NOT_BOUND:
- vdev->driver_bound = false;
- break;
- default:
- return NOTIFY_DONE;
- }
-
- complete(&vdev->probe_completion);
- return NOTIFY_OK;
-}
-
static struct gpio_virtuser_device *
to_gpio_virtuser_device(struct config_item *item)
{
@@ -1029,7 +998,7 @@ gpio_virtuser_device_is_live(struct gpio_virtuser_device *dev)
{
lockdep_assert_held(&dev->lock);

- return !!dev->pdev;
+ return !!dev->probe_data.pdev;
}

struct gpio_virtuser_lookup {
@@ -1369,7 +1338,7 @@ gpio_virtuser_device_config_dev_name_show(struct config_item *item,

guard(mutex)(&dev->lock);

- pdev = dev->pdev;
+ pdev = dev->probe_data.pdev;
if (pdev)
return sprintf(page, "%s\n", dev_name(&pdev->dev));

@@ -1478,7 +1447,6 @@ gpio_virtuser_device_activate(struct gpio_virtuser_device *dev)
{
struct platform_device_info pdevinfo;
struct fwnode_handle *swnode;
- struct platform_device *pdev;
int ret;

lockdep_assert_held(&dev->lock);
@@ -1499,31 +1467,12 @@ gpio_virtuser_device_activate(struct gpio_virtuser_device *dev)
if (ret)
goto err_remove_swnode;

- reinit_completion(&dev->probe_completion);
- dev->driver_bound = false;
- bus_register_notifier(&platform_bus_type, &dev->bus_notifier);
-
- pdev = platform_device_register_full(&pdevinfo);
- if (IS_ERR(pdev)) {
- ret = PTR_ERR(pdev);
- bus_unregister_notifier(&platform_bus_type, &dev->bus_notifier);
+ ret = dev_sync_probe_register(&dev->probe_data, &pdevinfo);
+ if (ret)
goto err_remove_lookup_table;
- }
-
- wait_for_completion(&dev->probe_completion);
- bus_unregister_notifier(&platform_bus_type, &dev->bus_notifier);
-
- if (!dev->driver_bound) {
- ret = -ENXIO;
- goto err_unregister_pdev;
- }
-
- dev->pdev = pdev;

return 0;

-err_unregister_pdev:
- platform_device_unregister(pdev);
err_remove_lookup_table:
gpio_virtuser_remove_lookup_table(dev);
err_remove_swnode:
@@ -1539,11 +1488,10 @@ gpio_virtuser_device_deactivate(struct gpio_virtuser_device *dev)

lockdep_assert_held(&dev->lock);

- swnode = dev_fwnode(&dev->pdev->dev);
- platform_device_unregister(dev->pdev);
+ swnode = dev_fwnode(&dev->probe_data.pdev->dev);
+ dev_sync_probe_unregister(&dev->probe_data);
gpio_virtuser_remove_lookup_table(dev);
fwnode_remove_software_node(swnode);
- dev->pdev = NULL;
}

static void
@@ -1772,8 +1720,7 @@ gpio_virtuser_config_make_device_group(struct config_group *group,
&gpio_virtuser_device_config_group_type);
mutex_init(&dev->lock);
INIT_LIST_HEAD(&dev->lookup_list);
- dev->bus_notifier.notifier_call = gpio_virtuser_bus_notifier_call;
- init_completion(&dev->probe_completion);
+ dev_sync_probe_init(&dev->probe_data);

return &no_free_ptr(dev)->group;
}
--
2.45.2