[PATCH v2] staging: gdm724x: fix returning -1 with return equivalent errors

[Rodrigo Gobbi <rodrigo.gobbi.7@xxxxxxxxx>]

As in the TODO file, use proper error codes from PM callbacks and init.

Signed-off-by: Rodrigo Gobbi <rodrigo.gobbi.7@xxxxxxxxx>
---
Changelog
    v2 minor changes at packet_type_to_tty_index() and gdm_usb_lte_init()
    v1 https://lore.kernel.org/linux-staging/20241004203458.6497-1-rodrigo.gobbi.7@xxxxxxxxx/T/#m258452a56ddade60b2209479f036213e72d43f02
---
 drivers/staging/gdm724x/TODO      |  1 -
 drivers/staging/gdm724x/gdm_mux.c |  6 +++---
 drivers/staging/gdm724x/gdm_usb.c | 10 ++++++----
 3 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/staging/gdm724x/TODO b/drivers/staging/gdm724x/TODO
index b2b571ecb063..56a415b9dcbe 100644
--- a/drivers/staging/gdm724x/TODO
+++ b/drivers/staging/gdm724x/TODO
@@ -2,7 +2,6 @@ TODO:
 - Clean up coding style to meet kernel standard. (80 line limit, netdev_err)
 - Remove test for host endian
 - Remove confusing macros (endian, hci_send, sdu_send, rcv_with_cb)
-- Fixes for every instances of function returning -1
 - Check for skb->len in gdm_lte_emulate_arp()
 - Use ALIGN() macro for dummy_cnt in up_to_host()
 - Error handling in init_usb()
diff --git a/drivers/staging/gdm724x/gdm_mux.c b/drivers/staging/gdm724x/gdm_mux.c
index 9b12619671a1..82302c6266eb 100644
--- a/drivers/staging/gdm724x/gdm_mux.c
+++ b/drivers/staging/gdm724x/gdm_mux.c
@@ -47,7 +47,7 @@ static int packet_type_to_tty_index(u16 packet_type)
 			return i;
 	}
 
-	return -1;
+	return -ENOENT;
 }
 
 static struct mux_tx *alloc_mux_tx(int len)
@@ -594,7 +594,7 @@ static int gdm_mux_suspend(struct usb_interface *intf, pm_message_t pm_msg)
 
 	if (mux_dev->usb_state != PM_NORMAL) {
 		dev_err(intf->usb_dev, "usb suspend - invalid state\n");
-		return -1;
+		return -EINVAL;
 	}
 
 	mux_dev->usb_state = PM_SUSPEND;
@@ -622,7 +622,7 @@ static int gdm_mux_resume(struct usb_interface *intf)
 
 	if (mux_dev->usb_state != PM_SUSPEND) {
 		dev_err(intf->usb_dev, "usb resume - invalid state\n");
-		return -1;
+		return -EINVAL;
 	}
 
 	mux_dev->usb_state = PM_NORMAL;
diff --git a/drivers/staging/gdm724x/gdm_usb.c b/drivers/staging/gdm724x/gdm_usb.c
index 54bdb64f52e8..f666fbeeb44c 100644
--- a/drivers/staging/gdm724x/gdm_usb.c
+++ b/drivers/staging/gdm724x/gdm_usb.c
@@ -916,7 +916,7 @@ static int gdm_usb_suspend(struct usb_interface *intf, pm_message_t pm_msg)
 	rx = &udev->rx;
 	if (udev->usb_state != PM_NORMAL) {
 		dev_err(intf->usb_dev, "usb suspend - invalid state\n");
-		return -1;
+		return -EINVAL;
 	}
 
 	udev->usb_state = PM_SUSPEND;
@@ -952,7 +952,7 @@ static int gdm_usb_resume(struct usb_interface *intf)
 
 	if (udev->usb_state != PM_SUSPEND) {
 		dev_err(intf->usb_dev, "usb resume - invalid state\n");
-		return -1;
+		return -EINVAL;
 	}
 	udev->usb_state = PM_NORMAL;
 
@@ -989,9 +989,11 @@ static struct usb_driver gdm_usb_lte_driver = {
 
 static int __init gdm_usb_lte_init(void)
 {
-	if (gdm_lte_event_init() < 0) {
+	int ret = gdm_lte_event_init();
+
+	if (ret < 0) {
 		pr_err("error creating event\n");
-		return -1;
+		return ret;
 	}
 
 	return usb_register(&gdm_usb_lte_driver);
-- 
2.34.1