Commit 3a27f40b authored by Bartosz Golaszewski's avatar Bartosz Golaszewski
Browse files

gpio: aggregator: stop using dev-sync-probe 



dev-err-probe is an overengineered solution to a simple problem. Use a
combination of wait_for_probe() and device_is_bound() to synchronously
wait for the platform device to probe.

Reviewed-by: default avatarLinus Walleij <linusw@kernel.org>
Link: https://patch.msgid.link/20260327-gpio-kill-dev-sync-probe-v1-2-efac254f1a1d@oss.qualcomm.com


Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
parent 7fb32879

drivers/gpio/Kconfig

+0 −1
Original line number Diff line number Diff line
@@ -2010,7 +2010,6 @@ menu "Virtual GPIO drivers" 
config GPIO_AGGREGATOR

	tristate "GPIO Aggregator"

	select CONFIGFS_FS

	select DEV_SYNC_PROBE

	help

	  Say yes here to enable the GPIO Aggregator, which provides a way to

	  aggregate existing GPIO lines into a new virtual GPIO chip.

drivers/gpio/gpio-aggregator.c

+21 −17
Original line number Diff line number Diff line
@@ -32,8 +32,6 @@ 
#include <linux/gpio/forwarder.h>

#include <linux/gpio/machine.h>



#include "dev-sync-probe.h"



#define AGGREGATOR_MAX_GPIOS 512

#define AGGREGATOR_LEGACY_PREFIX "_sysfs"
@@ -42,7 +40,7 @@ 
 */



struct gpio_aggregator {

	struct dev_sync_probe_data probe_data;

	struct platform_device *pdev;

	struct config_group group;

	struct gpiod_lookup_table *lookups;

	struct mutex lock;
@@ -135,7 +133,7 @@ static bool gpio_aggregator_is_active(struct gpio_aggregator *aggr) 
{

	lockdep_assert_held(&aggr->lock);



	return aggr->probe_data.pdev && platform_get_drvdata(aggr->probe_data.pdev);

	return aggr->pdev && platform_get_drvdata(aggr->pdev);

}



/* Only aggregators created via legacy sysfs can be "activating". */
@@ -143,7 +141,7 @@ static bool gpio_aggregator_is_activating(struct gpio_aggregator *aggr) 
{

	lockdep_assert_held(&aggr->lock);



	return aggr->probe_data.pdev && !platform_get_drvdata(aggr->probe_data.pdev);

	return aggr->pdev && !platform_get_drvdata(aggr->pdev);

}



static size_t gpio_aggregator_count_lines(struct gpio_aggregator *aggr)
@@ -909,6 +907,7 @@ static int gpio_aggregator_activate(struct gpio_aggregator *aggr) 
{

	struct platform_device_info pdevinfo;

	struct gpio_aggregator_line *line;

	struct platform_device *pdev;

	struct fwnode_handle *swnode;

	unsigned int n = 0;

	int ret = 0;
@@ -962,12 +961,23 @@ static int gpio_aggregator_activate(struct gpio_aggregator *aggr) 


	gpiod_add_lookup_table(aggr->lookups);



	ret = dev_sync_probe_register(&aggr->probe_data, &pdevinfo);

	if (ret)

	pdev = platform_device_register_full(&pdevinfo);

	if (IS_ERR(pdev)) {

		ret = PTR_ERR(pdev);

		goto err_remove_lookup_table;

	}



	wait_for_device_probe();

	if (!device_is_bound(&pdev->dev)) {

		ret = -ENXIO;

		goto err_unregister_pdev;

	}



	aggr->pdev = pdev;

	return 0;



err_unregister_pdev:

	platform_device_unregister(pdev);

err_remove_lookup_table:

	kfree(aggr->lookups->dev_id);

	gpiod_remove_lookup_table(aggr->lookups);
@@ -981,7 +991,8 @@ static int gpio_aggregator_activate(struct gpio_aggregator *aggr) 


static void gpio_aggregator_deactivate(struct gpio_aggregator *aggr)

{

	dev_sync_probe_unregister(&aggr->probe_data);

	platform_device_unregister(aggr->pdev);

	aggr->pdev = NULL;

	gpiod_remove_lookup_table(aggr->lookups);

	kfree(aggr->lookups->dev_id);

	kfree(aggr->lookups);
@@ -1145,7 +1156,7 @@ gpio_aggregator_device_dev_name_show(struct config_item *item, char *page) 


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



	pdev = aggr->probe_data.pdev;

	pdev = aggr->pdev;

	if (pdev)

		return sysfs_emit(page, "%s\n", dev_name(&pdev->dev));
@@ -1322,7 +1333,6 @@ gpio_aggregator_make_group(struct config_group *group, const char *name) 
		return ERR_PTR(ret);



	config_group_init_type_name(&aggr->group, name, &gpio_aggregator_device_type);

	dev_sync_probe_init(&aggr->probe_data);



	return &aggr->group;

}
@@ -1471,12 +1481,6 @@ static ssize_t gpio_aggregator_new_device_store(struct device_driver *driver, 
	scnprintf(name, sizeof(name), "%s.%d", AGGREGATOR_LEGACY_PREFIX, aggr->id);

	config_group_init_type_name(&aggr->group, name, &gpio_aggregator_device_type);



	/*

	 * Since the device created by sysfs might be toggled via configfs

	 * 'live' attribute later, this initialization is needed.

	 */

	dev_sync_probe_init(&aggr->probe_data);



	/* Expose to configfs */

	res = configfs_register_group(&gpio_aggregator_subsys.su_group,

				      &aggr->group);
@@ -1495,7 +1499,7 @@ static ssize_t gpio_aggregator_new_device_store(struct device_driver *driver, 
		goto remove_table;

	}



	aggr->probe_data.pdev = pdev;

	aggr->pdev = pdev;

	module_put(THIS_MODULE);

	return count;