[PATCH] platform/x86: panasonic-laptop: simplify allocation of sinf

[Rosen Penev <rosenp@gmail.com>]

Change to a flexible array member to allocate once instead of twice.

Use __counted_by for extra runtime analysis. Move the counting
variable assignment to right after allocation as done by
kzalloc_flex for GCC 15 and above.

Remove + 1 to allocation. It's already done in the previous line.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 v3: Rephrased.
 v2: Rebased.
 drivers/platform/x86/panasonic-laptop.c | 19 +++++--------------
 1 file changed, 5 insertions(+), 14 deletions(-)

diff --git a/drivers/platform/x86/panasonic-laptop.c b/drivers/platform/x86/panasonic-laptop.c
index 1337f7c49805..2fe8ff0d32a8 100644
--- a/drivers/platform/x86/panasonic-laptop.c
+++ b/drivers/platform/x86/panasonic-laptop.c
@@ -246,11 +246,11 @@ struct pcc_acpi {
 	int			ac_brightness;
 	int			dc_brightness;
 	int			current_brightness;
-	u32			*sinf;
 	struct acpi_device	*device;
 	struct input_dev	*input_dev;
 	struct backlight_device	*backlight;
 	struct platform_device	*platform;
+	u32			sinf[] __counted_by(num_sifr);
 };

 /*
@@ -1003,21 +1003,15 @@ static int acpi_pcc_hotkey_probe(struct platform_device *pdev)
 	 */
 	num_sifr++;

-	pcc = kzalloc_obj(struct pcc_acpi);
+	pcc = kzalloc_flex(*pcc, sinf, num_sifr);
 	if (!pcc) {
 		pr_err("Couldn't allocate mem for pcc");
 		return -ENOMEM;
 	}

-	pcc->sinf = kcalloc(num_sifr + 1, sizeof(u32), GFP_KERNEL);
-	if (!pcc->sinf) {
-		result = -ENOMEM;
-		goto out_hotkey;
-	}
-
+	pcc->num_sifr = num_sifr;
 	pcc->device = device;
 	pcc->handle = device->handle;
-	pcc->num_sifr = num_sifr;
 	device->driver_data = pcc;
 	strscpy(acpi_device_name(device), ACPI_PCC_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_PCC_CLASS);
@@ -1025,7 +1019,7 @@ static int acpi_pcc_hotkey_probe(struct platform_device *pdev)
 	result = acpi_pcc_init_input(pcc);
 	if (result) {
 		pr_err("Error installing keyinput handler\n");
-		goto out_sinf;
+		goto out_hotkey;
 	}

 	if (!acpi_pcc_retrieve_biosdata(pcc)) {
@@ -1106,10 +1100,8 @@ static int acpi_pcc_hotkey_probe(struct platform_device *pdev)
 	backlight_device_unregister(pcc->backlight);
 out_input:
 	input_unregister_device(pcc->input_dev);
-out_sinf:
-	device->driver_data = NULL;
-	kfree(pcc->sinf);
 out_hotkey:
+	device->driver_data = NULL;
 	kfree(pcc);

 	return result;
@@ -1139,7 +1131,6 @@ static void acpi_pcc_hotkey_remove(struct platform_device *pdev)

 	device->driver_data = NULL;

-	kfree(pcc->sinf);
 	kfree(pcc);
 }

--
2.54.0