[PATCH 16/23] gpio: mockup: refactor the module init function

[Bartosz Golaszewski <brgl@xxxxxxxx>]

From: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>

This is in preparation for dynamically created chips.

Let's split out the code that can be reused when creating chips at
run-time. Let's also move the code preparing the device properties into
a separate routine. This has the advantage of simplifying the error
handling.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx>
---
 drivers/gpio/gpio-mockup.c | 165 ++++++++++++++++++++-----------------
 1 file changed, 90 insertions(+), 75 deletions(-)

diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
index 995e37fef9c5..eb94ddac5fee 100644
--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -524,16 +524,78 @@ static __init char **gpio_mockup_make_line_names(const char *label,
 	return names;
 }
 
-static int __init gpio_mockup_init(void)
+static int __init gpio_mockup_register_device(struct property_entry *properties)
 {
-	struct property_entry properties[GPIO_MOCKUP_MAX_PROP];
-	char chip_label[GPIO_MOCKUP_LABEL_SIZE];
 	struct gpio_mockup_device *mockup_dev;
-	int i, prop, num_chips, err = 0, base;
 	struct platform_device_info pdevinfo;
-	char **line_names;
+
+	memset(&pdevinfo, 0, sizeof(pdevinfo));
+
+	mockup_dev = kzalloc(sizeof(*mockup_dev), GFP_KERNEL);
+	if (!mockup_dev)
+		return -ENOMEM;
+
+	pdevinfo.name = "gpio-mockup";
+	pdevinfo.properties = properties;
+
+	pdevinfo.id = ida_alloc(&gpio_mockup_ida, GFP_KERNEL);
+	if (pdevinfo.id < 0) {
+		kfree(mockup_dev);
+		return pdevinfo.id;
+	}
+
+	mockup_dev->pdev = platform_device_register_full(&pdevinfo);
+	if (IS_ERR(mockup_dev->pdev)) {
+		ida_free(&gpio_mockup_ida, pdevinfo.id);
+		kfree(mockup_dev);
+		return PTR_ERR(mockup_dev->pdev);
+	}
+
+	list_add(&mockup_dev->list, &gpio_mockup_devices);
+
+	return 0;
+}
+
+static int __init gpio_mockup_register_one_chip_from_params(int idx)
+{
+	char chip_label[GPIO_MOCKUP_LABEL_SIZE], **line_names = NULL;
+	struct property_entry properties[GPIO_MOCKUP_MAX_PROP];
+	int prop = 0, base, ret;
 	u16 ngpio;
 
+	memset(properties, 0, sizeof(properties));
+
+	snprintf(chip_label, sizeof(chip_label), "gpio-mockup-%c", idx + 'A');
+	properties[prop++] = PROPERTY_ENTRY_STRING("chip-label",
+						   chip_label);
+
+	base = gpio_mockup_range_base(idx);
+	if (base >= 0)
+		properties[prop++] = PROPERTY_ENTRY_U32("gpio-base",
+							base);
+
+	ngpio = base < 0 ? gpio_mockup_range_ngpio(idx)
+			 : gpio_mockup_range_ngpio(idx) - base;
+	properties[prop++] = PROPERTY_ENTRY_U16("nr-gpios", ngpio);
+
+	if (gpio_mockup_named_lines) {
+		line_names = gpio_mockup_make_line_names(chip_label, ngpio);
+		if (!line_names)
+			return -ENOMEM;
+
+		properties[prop++] = PROPERTY_ENTRY_STRING_ARRAY_LEN(
+					"gpio-line-names", line_names, ngpio);
+	}
+
+	ret = gpio_mockup_register_device(properties);
+	kfree_strarray(line_names, ngpio);
+	return ret;
+}
+
+static int __init gpio_mockup_register_chips_from_params(void)
+{
+	int num_chips, i, ret;
+
 	if ((gpio_mockup_num_ranges < 2) ||
 	    (gpio_mockup_num_ranges % 2) ||
 	    (gpio_mockup_num_ranges > GPIO_MOCKUP_MAX_RANGES))
@@ -551,86 +613,39 @@ static int __init gpio_mockup_init(void)
 			return -EINVAL;
 	}
 
-	gpio_mockup_dbg_dir = debugfs_create_dir("gpio-mockup", NULL);
-
-	err = platform_driver_register(&gpio_mockup_driver);
-	if (err) {
-		pr_err("error registering platform driver\n");
-		debugfs_remove_recursive(gpio_mockup_dbg_dir);
-		return err;
-	}
-
 	for (i = 0; i < num_chips; i++) {
-		memset(properties, 0, sizeof(properties));
-		memset(&pdevinfo, 0, sizeof(pdevinfo));
-		prop = 0;
-		line_names = NULL;
-
-		snprintf(chip_label, sizeof(chip_label),
-			 "gpio-mockup-%c", i + 'A');
-		properties[prop++] = PROPERTY_ENTRY_STRING("chip-label",
-							   chip_label);
-
-		base = gpio_mockup_range_base(i);
-		if (base >= 0)
-			properties[prop++] = PROPERTY_ENTRY_U32("gpio-base",
-								base);
-
-		ngpio = base < 0 ? gpio_mockup_range_ngpio(i)
-				 : gpio_mockup_range_ngpio(i) - base;
-		properties[prop++] = PROPERTY_ENTRY_U16("nr-gpios", ngpio);
-
-		if (gpio_mockup_named_lines) {
-			line_names = gpio_mockup_make_line_names(chip_label,
-								 ngpio);
-			if (!line_names) {
-				err = -ENOMEM;
-				goto err_out;
-			}
-
-			properties[prop++] = PROPERTY_ENTRY_STRING_ARRAY_LEN(
-						"gpio-line-names",
-						line_names, ngpio);
+		ret = gpio_mockup_register_one_chip_from_params(i);
+		if (ret) {
+			gpio_mockup_unregister_devices();
+			return ret;
 		}
+	}
 
-		pdevinfo.name = "gpio-mockup";
-		pdevinfo.properties = properties;
+	return 0;
+}
 
-		pdevinfo.id = ida_alloc(&gpio_mockup_ida, GFP_KERNEL);
-		if (pdevinfo.id < 0) {
-			kfree_strarray(line_names, ngpio);
-			err = pdevinfo.id;
-			goto err_out;
-		}
+static int __init gpio_mockup_init(void)
+{
+	int ret;
 
-		mockup_dev = kzalloc(sizeof(*mockup_dev), GFP_KERNEL);
-		if (!mockup_dev) {
-			kfree_strarray(line_names, ngpio);
-			ida_free(&gpio_mockup_ida, pdevinfo.id);
-			err = -ENOMEM;
-			goto err_out;
-		}
+	gpio_mockup_dbg_dir = debugfs_create_dir("gpio-mockup", NULL);
 
-		mockup_dev->pdev = platform_device_register_full(&pdevinfo);
-		kfree_strarray(line_names, ngpio);
-		if (IS_ERR(mockup_dev->pdev)) {
-			pr_err("error registering device");
-			ida_free(&gpio_mockup_ida, pdevinfo.id);
-			kfree(mockup_dev);
-			err = PTR_ERR(mockup_dev->pdev);
-			goto err_out;
-		}
+	ret = platform_driver_register(&gpio_mockup_driver);
+	if (ret) {
+		pr_err("error registering platform driver\n");
+		debugfs_remove_recursive(gpio_mockup_dbg_dir);
+		return ret;
+	}
 
-		list_add(&mockup_dev->list, &gpio_mockup_devices);
+	ret = gpio_mockup_register_chips_from_params();
+	if (ret) {
+		pr_err("error registering device");
+		debugfs_remove_recursive(gpio_mockup_dbg_dir);
+		platform_driver_unregister(&gpio_mockup_driver);
+		return ret;
 	}
 
 	return 0;
-
-err_out:
-	platform_driver_unregister(&gpio_mockup_driver);
-	gpio_mockup_unregister_devices();
-	debugfs_remove_recursive(gpio_mockup_dbg_dir);
-	return err;
 }
 
 static void __exit gpio_mockup_exit(void)
-- 
2.26.1