Commit 5cfbd0eb authored by Bartosz Golaszewski's avatar Bartosz Golaszewski
Browse files

gpio: sim: use fwnode-based GPIO hogs 



Convert gpio-sim to using software nodes for setting up simulated hogs
instead of legacy machine hogs.

Reviewed-by: default avatarLinus Walleij <linusw@kernel.org>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20260309-gpio-hog-fwnode-v2-3-4e61f3dbf06a@oss.qualcomm.com


Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
parent d1d564ec

drivers/gpio/gpio-sim.c

+56 −106
Original line number Diff line number Diff line
@@ -40,6 +40,7 @@ 


#define GPIO_SIM_NGPIO_MAX	1024

#define GPIO_SIM_PROP_MAX	5 /* Max 4 properties + sentinel. */

#define GPIO_SIM_HOG_PROP_MAX	5

#define GPIO_SIM_NUM_ATTRS	3 /* value, pull and sentinel */



static DEFINE_IDA(gpio_sim_ida);
@@ -561,8 +562,6 @@ struct gpio_sim_device { 
	 */

	struct mutex lock;



	struct gpiod_hog *hogs;



	struct list_head bank_list;

};
@@ -774,102 +773,6 @@ static void gpio_sim_set_reserved_ranges(struct gpio_sim_bank *bank, 
	}

}



static void gpio_sim_remove_hogs(struct gpio_sim_device *dev)

{

	struct gpiod_hog *hog;



	if (!dev->hogs)

		return;



	gpiod_remove_hogs(dev->hogs);



	for (hog = dev->hogs; hog->chip_label; hog++) {

		kfree(hog->chip_label);

		kfree(hog->line_name);

	}



	kfree(dev->hogs);

	dev->hogs = NULL;

}



static int gpio_sim_add_hogs(struct gpio_sim_device *dev)

{

	unsigned int num_hogs = 0, idx = 0;

	struct gpio_sim_bank *bank;

	struct gpio_sim_line *line;

	struct gpiod_hog *hog;



	list_for_each_entry(bank, &dev->bank_list, siblings) {

		list_for_each_entry(line, &bank->line_list, siblings) {

			if (line->offset >= bank->num_lines)

				continue;



			if (line->hog)

				num_hogs++;

		}

	}



	if (!num_hogs)

		return 0;



	/* Allocate one more for the sentinel. */

	dev->hogs = kzalloc_objs(*dev->hogs, num_hogs + 1);

	if (!dev->hogs)

		return -ENOMEM;



	list_for_each_entry(bank, &dev->bank_list, siblings) {

		list_for_each_entry(line, &bank->line_list, siblings) {

			if (line->offset >= bank->num_lines)

				continue;



			if (!line->hog)

				continue;



			hog = &dev->hogs[idx++];



			/*

			 * We need to make this string manually because at this

			 * point the device doesn't exist yet and so dev_name()

			 * is not available.

			 */

			if (gpio_sim_bank_has_label(bank))

				hog->chip_label = kstrdup(bank->label,

							  GFP_KERNEL);

			else

				hog->chip_label = kasprintf(GFP_KERNEL,

							"gpio-sim.%u:%pfwP",

							dev->id,

							bank->swnode);

			if (!hog->chip_label) {

				gpio_sim_remove_hogs(dev);

				return -ENOMEM;

			}



			/*

			 * We need to duplicate this because the hog config

			 * item can be removed at any time (and we can't block

			 * it) and gpiolib doesn't make a deep copy of the hog

			 * data.

			 */

			if (line->hog->name) {

				hog->line_name = kstrdup(line->hog->name,

							 GFP_KERNEL);

				if (!hog->line_name) {

					gpio_sim_remove_hogs(dev);

					return -ENOMEM;

				}

			}



			hog->chip_hwnum = line->offset;

			hog->dflags = line->hog->dir;

		}

	}



	gpiod_add_hogs(dev->hogs);



	return 0;

}



static struct fwnode_handle *

gpio_sim_make_bank_swnode(struct gpio_sim_bank *bank,

			  struct fwnode_handle *parent)
@@ -917,12 +820,61 @@ gpio_sim_make_bank_swnode(struct gpio_sim_bank *bank, 
	return fwnode_create_software_node(properties, parent);

}



static int gpio_sim_bank_add_hogs(struct gpio_sim_bank *bank)

{

	struct property_entry properties[GPIO_SIM_HOG_PROP_MAX];

	struct fwnode_handle *swnode;

	struct gpio_sim_line *line;

	struct gpio_sim_hog *hog;

	unsigned int idx;

	u32 gpios[2];



	list_for_each_entry(line, &bank->line_list, siblings) {

		if (!line->hog)

			continue;



		hog = line->hog;



		gpios[0] = line->offset;

		gpios[1] = 0;



		memset(properties, 0, sizeof(properties));



		idx = 0;

		properties[idx++] = PROPERTY_ENTRY_BOOL("gpio-hog");

		properties[idx++] = PROPERTY_ENTRY_U32_ARRAY("gpios", gpios);

		properties[idx++] = PROPERTY_ENTRY_STRING("line-name", hog->name);



		switch (hog->dir) {

		case GPIOD_IN:

			properties[idx++] = PROPERTY_ENTRY_BOOL("input");

			break;

		case GPIOD_OUT_HIGH:

			properties[idx++] = PROPERTY_ENTRY_BOOL("output-high");

			break;

		case GPIOD_OUT_LOW:

			properties[idx++] = PROPERTY_ENTRY_BOOL("output-low");

			break;

		default:

			/* Would have been validated at configfs store. */

			WARN(1, "Unexpected hog direction value: %d", hog->dir);

			return -EINVAL;

		}



		swnode = fwnode_create_software_node(properties, bank->swnode);

		if (IS_ERR(swnode))

			return PTR_ERR(swnode);

	}



	return 0;

}



static void gpio_sim_remove_swnode_recursive(struct fwnode_handle *swnode)

{

	struct fwnode_handle *child;



	fwnode_for_each_child_node(swnode, child)

		fwnode_remove_software_node(child);

		gpio_sim_remove_swnode_recursive(child);



	fwnode_remove_software_node(swnode);

}
@@ -977,13 +929,13 @@ static int gpio_sim_device_activate(struct gpio_sim_device *dev) 
			gpio_sim_remove_swnode_recursive(swnode);

			return ret;

		}

	}



	ret = gpio_sim_add_hogs(dev);

		ret = gpio_sim_bank_add_hogs(bank);

		if (ret) {

			gpio_sim_remove_swnode_recursive(swnode);

			return ret;

		}

	}



	pdevinfo.name = "gpio-sim";

	pdevinfo.fwnode = swnode;
@@ -991,7 +943,6 @@ static int gpio_sim_device_activate(struct gpio_sim_device *dev) 


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

	if (ret) {

		gpio_sim_remove_hogs(dev);

		gpio_sim_remove_swnode_recursive(swnode);

		return ret;

	}
@@ -1007,7 +958,6 @@ static void gpio_sim_device_deactivate(struct gpio_sim_device *dev) 


	swnode = dev_fwnode(&dev->probe_data.pdev->dev);

	dev_sync_probe_unregister(&dev->probe_data);

	gpio_sim_remove_hogs(dev);

	gpio_sim_remove_swnode_recursive(swnode);

}