diff mbox series

[5/8] platform/x86: x86-android-tablets: Create a platform_device from module_init()

Message ID 20230909141816.58358-6-hdegoede@redhat.com
State Accepted
Commit 8b57d33a6fdbb53d03da762b31e65a1027f74caf
Headers show
Series x86-android-tablets: Stop using gpiolib private APIs | expand

Commit Message

Hans de Goede Sept. 9, 2023, 2:18 p.m. UTC 
Create a platform_device from module_init() and change
x86_android_tablet_init() / cleanup() into platform_device
probe() and remove() functions.

This is a preparation patch for refactoring x86_android_tablet_get_gpiod()
to no longer use gpiolib private functions like gpiochip_find().

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 .../platform/x86/x86-android-tablets/core.c   | 57 ++++++++++++++-----
 1 file changed, 44 insertions(+), 13 deletions(-)

Comments

Andy Shevchenko Sept. 10, 2023, 8:07 a.m. UTC | #1 
On Sat, Sep 9, 2023 at 5:18 PM Hans de Goede <hdegoede@redhat.com> wrote:
>
> Create a platform_device from module_init() and change
> x86_android_tablet_init() / cleanup() into platform_device
> probe() and remove() functions.
>
> This is a preparation patch for refactoring x86_android_tablet_get_gpiod()
> to no longer use gpiolib private functions like gpiochip_find().

...

> +static int __init x86_android_tablet_init(void)
> +{

> +       if (!dmi_first_match(x86_android_tablet_ids)) {

Why do we need this? Module alias is based on DMI matching, is it
against manual loading?

> +               pr_err("error loaded on unknown tablet model\n");
> +               return -ENODEV;
> +       }
> +
> +       x86_android_tablet_device = platform_create_bundle(&x86_android_tablet_driver,
> +                                                  x86_android_tablet_probe,
> +                                                  NULL, 0, NULL, 0);

So, in case of manual loading, would it be harmful for non-listed platforms?

> +       return PTR_ERR_OR_ZERO(x86_android_tablet_device);
> +}
> +
> +static void __exit x86_android_tablet_exit(void)
> +{
> +       platform_device_unregister(x86_android_tablet_device);
> +       platform_driver_unregister(&x86_android_tablet_driver);
> +}

> +

Instead of adding this blank line you can move
module_init()/module_exit() closer to the respective callbacks.

>  module_init(x86_android_tablet_init);
> -module_exit(x86_android_tablet_cleanup);
> +module_exit(x86_android_tablet_exit);
Hans de Goede Sept. 10, 2023, 11:19 a.m. UTC | #2 
Hi,

On 9/10/23 10:07, Andy Shevchenko wrote:
> On Sat, Sep 9, 2023 at 5:18 PM Hans de Goede <hdegoede@redhat.com> wrote:
>>
>> Create a platform_device from module_init() and change
>> x86_android_tablet_init() / cleanup() into platform_device
>> probe() and remove() functions.
>>
>> This is a preparation patch for refactoring x86_android_tablet_get_gpiod()
>> to no longer use gpiolib private functions like gpiochip_find().
> 
> ...
> 
>> +static int __init x86_android_tablet_init(void)
>> +{
> 
>> +       if (!dmi_first_match(x86_android_tablet_ids)) {
> 
> Why do we need this? Module alias is based on DMI matching, is it
> against manual loading?

Yes I added this to protect against manual loading.

> 
>> +               pr_err("error loaded on unknown tablet model\n");
>> +               return -ENODEV;
>> +       }
>> +
>> +       x86_android_tablet_device = platform_create_bundle(&x86_android_tablet_driver,
>> +                                                  x86_android_tablet_probe,
>> +                                                  NULL, 0, NULL, 0);
> 
> So, in case of manual loading, would it be harmful for non-listed platforms?

No this will not be harmful, x86_android_tablet_probe() also
checks the DMI table and it will return -ENODEV when there is
no match.

So we just end up with an unused x86_android_tablets platform-device
and otherwise no harm is done.

I guess my main reason here is to not change manual loading
behavior, before the entire insmod would fail since
module_init() would return -ENODEV, this preserves this
behavior.

But you are right that this check can be dropped without
any bad side-effects.

I'll drop the check before merging this.

> 
>> +       return PTR_ERR_OR_ZERO(x86_android_tablet_device);
>> +}
>> +
>> +static void __exit x86_android_tablet_exit(void)
>> +{
>> +       platform_device_unregister(x86_android_tablet_device);
>> +       platform_driver_unregister(&x86_android_tablet_driver);
>> +}
> 
>> +
> 
> Instead of adding this blank line you can move
> module_init()/module_exit() closer to the respective callbacks.

Ack, I'll fix this before merging this.

Regards,

Hans



> 
>>  module_init(x86_android_tablet_init);
>> -module_exit(x86_android_tablet_cleanup);
>> +module_exit(x86_android_tablet_exit);
>
diff mbox series

Patch

diff --git a/drivers/platform/x86/x86-android-tablets/core.c b/drivers/platform/x86/x86-android-tablets/core.c
index ab8cf22ac5da..3d3101b2848f 100644
--- a/drivers/platform/x86/x86-android-tablets/core.c
+++ b/drivers/platform/x86/x86-android-tablets/core.c
@@ -25,6 +25,8 @@ 
 #include "../../../gpio/gpiolib.h"
 #include "../../../gpio/gpiolib-acpi.h"
 
+static struct platform_device *x86_android_tablet_device;
+
 static int gpiochip_find_match_label(struct gpio_chip *gc, void *data)
 {
 	return gc->label && !strcmp(gc->label, data);
@@ -224,7 +226,7 @@  static __init int x86_instantiate_serdev(const struct x86_serdev_info *info, int
 	return ret;
 }
 
-static void x86_android_tablet_cleanup(void)
+static void x86_android_tablet_remove(struct platform_device *pdev)
 {
 	int i;
 
@@ -255,7 +257,7 @@  static void x86_android_tablet_cleanup(void)
 	software_node_unregister(bat_swnode);
 }
 
-static __init int x86_android_tablet_init(void)
+static __init int x86_android_tablet_probe(struct platform_device *pdev)
 {
 	const struct x86_dev_info *dev_info;
 	const struct dmi_system_id *id;
@@ -266,6 +268,8 @@  static __init int x86_android_tablet_init(void)
 		return -ENODEV;
 
 	dev_info = id->driver_data;
+	/* Allow x86_android_tablet_device use before probe() exits */
+	x86_android_tablet_device = pdev;
 
 	/*
 	 * Since this runs from module_init() it cannot use -EPROBE_DEFER,
@@ -288,7 +292,7 @@  static __init int x86_android_tablet_init(void)
 	if (dev_info->init) {
 		ret = dev_info->init();
 		if (ret < 0) {
-			x86_android_tablet_cleanup();
+			x86_android_tablet_remove(pdev);
 			return ret;
 		}
 		exit_handler = dev_info->exit;
@@ -296,7 +300,7 @@  static __init int x86_android_tablet_init(void)
 
 	i2c_clients = kcalloc(dev_info->i2c_client_count, sizeof(*i2c_clients), GFP_KERNEL);
 	if (!i2c_clients) {
-		x86_android_tablet_cleanup();
+		x86_android_tablet_remove(pdev);
 		return -ENOMEM;
 	}
 
@@ -304,7 +308,7 @@  static __init int x86_android_tablet_init(void)
 	for (i = 0; i < i2c_client_count; i++) {
 		ret = x86_instantiate_i2c_client(dev_info, i);
 		if (ret < 0) {
-			x86_android_tablet_cleanup();
+			x86_android_tablet_remove(pdev);
 			return ret;
 		}
 	}
@@ -312,7 +316,7 @@  static __init int x86_android_tablet_init(void)
 	/* + 1 to make space for (optional) gpio_keys_button pdev */
 	pdevs = kcalloc(dev_info->pdev_count + 1, sizeof(*pdevs), GFP_KERNEL);
 	if (!pdevs) {
-		x86_android_tablet_cleanup();
+		x86_android_tablet_remove(pdev);
 		return -ENOMEM;
 	}
 
@@ -320,14 +324,14 @@  static __init int x86_android_tablet_init(void)
 	for (i = 0; i < pdev_count; i++) {
 		pdevs[i] = platform_device_register_full(&dev_info->pdev_info[i]);
 		if (IS_ERR(pdevs[i])) {
-			x86_android_tablet_cleanup();
+			x86_android_tablet_remove(pdev);
 			return PTR_ERR(pdevs[i]);
 		}
 	}
 
 	serdevs = kcalloc(dev_info->serdev_count, sizeof(*serdevs), GFP_KERNEL);
 	if (!serdevs) {
-		x86_android_tablet_cleanup();
+		x86_android_tablet_remove(pdev);
 		return -ENOMEM;
 	}
 
@@ -335,7 +339,7 @@  static __init int x86_android_tablet_init(void)
 	for (i = 0; i < serdev_count; i++) {
 		ret = x86_instantiate_serdev(&dev_info->serdev_info[i], i);
 		if (ret < 0) {
-			x86_android_tablet_cleanup();
+			x86_android_tablet_remove(pdev);
 			return ret;
 		}
 	}
@@ -346,7 +350,7 @@  static __init int x86_android_tablet_init(void)
 
 		buttons = kcalloc(dev_info->gpio_button_count, sizeof(*buttons), GFP_KERNEL);
 		if (!buttons) {
-			x86_android_tablet_cleanup();
+			x86_android_tablet_remove(pdev);
 			return -ENOMEM;
 		}
 
@@ -354,7 +358,7 @@  static __init int x86_android_tablet_init(void)
 			ret = x86_android_tablet_get_gpiod(dev_info->gpio_button[i].chip,
 							   dev_info->gpio_button[i].pin, &gpiod);
 			if (ret < 0) {
-				x86_android_tablet_cleanup();
+				x86_android_tablet_remove(pdev);
 				return ret;
 			}
 
@@ -369,7 +373,7 @@  static __init int x86_android_tablet_init(void)
 								  PLATFORM_DEVID_AUTO,
 								  &pdata, sizeof(pdata));
 		if (IS_ERR(pdevs[pdev_count])) {
-			x86_android_tablet_cleanup();
+			x86_android_tablet_remove(pdev);
 			return PTR_ERR(pdevs[pdev_count]);
 		}
 		pdev_count++;
@@ -378,8 +382,35 @@  static __init int x86_android_tablet_init(void)
 	return 0;
 }
 
+static struct platform_driver x86_android_tablet_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+	},
+	.remove_new = x86_android_tablet_remove,
+};
+
+static int __init x86_android_tablet_init(void)
+{
+	if (!dmi_first_match(x86_android_tablet_ids)) {
+		pr_err("error loaded on unknown tablet model\n");
+		return -ENODEV;
+	}
+
+	x86_android_tablet_device = platform_create_bundle(&x86_android_tablet_driver,
+						   x86_android_tablet_probe,
+						   NULL, 0, NULL, 0);
+
+	return PTR_ERR_OR_ZERO(x86_android_tablet_device);
+}
+
+static void __exit x86_android_tablet_exit(void)
+{
+	platform_device_unregister(x86_android_tablet_device);
+	platform_driver_unregister(&x86_android_tablet_driver);
+}
+
 module_init(x86_android_tablet_init);
-module_exit(x86_android_tablet_cleanup);
+module_exit(x86_android_tablet_exit);
 
 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
 MODULE_DESCRIPTION("X86 Android tablets DSDT fixups driver");