[PATCH 1/2] staging: rtl8723bs: use guard(mutex) to simplify locking

[Samrudh Nelli]

Replace classic mutex_lock() / mutex_unlock() pairs with the
guard(mutex) macro in functions where the lock is held for the
remainder of the execution scope.

This simplifies the code, eliminates the need for goto-based
error handling (e.g., in cpwm_int_hdl()), and ensures that
locks are always released gracefully when the function returns,
preventing future deadlocks if new exit paths are added.

Functions where the lock is intentionally dropped before the
function exits have been left untouched.

Signed-off-by: Samrudh Nelli <samrudhnelli@xxxxxxxxx>
---
 drivers/staging/rtl8723bs/core/rtw_pwrctrl.c | 33 ++++++--------------
 1 file changed, 10 insertions(+), 23 deletions(-)

diff --git a/drivers/staging/rtl8723bs/core/rtw_pwrctrl.c b/drivers/staging/rtl8723bs/core/rtw_pwrctrl.c
index 448611ad8237..18163a3dbade 100644
--- a/drivers/staging/rtl8723bs/core/rtw_pwrctrl.c
+++ b/drivers/staging/rtl8723bs/core/rtw_pwrctrl.c
@@ -7,6 +7,7 @@
 #include <drv_types.h>
 #include <hal_data.h>
 #include <linux/jiffies.h>
+#include <linux/cleanup.h>
 
 void _ips_enter(struct adapter *padapter)
 {
@@ -37,9 +38,8 @@ void ips_enter(struct adapter *padapter)
 
 	hal_btcoex_IpsNotify(padapter, pwrpriv->ips_mode_req);
 
-	mutex_lock(&pwrpriv->lock);
+	guard(mutex)(&pwrpriv->lock);
 	_ips_enter(padapter);
-	mutex_unlock(&pwrpriv->lock);
 }
 
 int _ips_leave(struct adapter *padapter)
@@ -337,7 +337,7 @@ void rtw_set_ps_mode(struct adapter *padapter, u8 ps_mode,
 		if (ps_mode == PS_MODE_ACTIVE)
 			return;
 
-	mutex_lock(&pwrpriv->lock);
+	guard(mutex)(&pwrpriv->lock);
 
 	/* if (pwrpriv->pwr_mode == PS_MODE_ACTIVE) */
 	if (ps_mode == PS_MODE_ACTIVE) {
@@ -383,8 +383,6 @@ void rtw_set_ps_mode(struct adapter *padapter, u8 ps_mode,
 			rtw_set_rpwm(padapter, pslv);
 		}
 	}
-
-	mutex_unlock(&pwrpriv->lock);
 }
 
 /*
@@ -578,10 +576,10 @@ void cpwm_int_hdl(struct adapter *padapter, struct reportpwrstate_parm *preportp
 
 	pwrpriv = adapter_to_pwrctl(padapter);
 
-	mutex_lock(&pwrpriv->lock);
+	guard(mutex)(&pwrpriv->lock);
 
 	if (pwrpriv->rpwm < PS_STATE_S2)
-		goto exit;
+		return;
 
 	pwrpriv->cpwm = PS_STATE(preportpwrstate->state);
 	pwrpriv->cpwm_tog = preportpwrstate->state & PS_TOGGLE;
@@ -593,9 +591,6 @@ void cpwm_int_hdl(struct adapter *padapter, struct reportpwrstate_parm *preportp
 		if (pwrpriv->alives & XMIT_ALIVE)
 			complete(&padapter->xmitpriv.xmit_comp);
 	}
-
-exit:
-	mutex_unlock(&pwrpriv->lock);
 }
 
 static void cpwm_event_callback(struct work_struct *work)
@@ -744,7 +739,7 @@ void rtw_unregister_task_alive(struct adapter *padapter, u32 task)
 			pslv = PS_STATE_S2;
 	}
 
-	mutex_lock(&pwrctrl->lock);
+	guard(mutex)(&pwrctrl->lock);
 
 	unregister_task_alive(pwrctrl, task);
 
@@ -754,8 +749,6 @@ void rtw_unregister_task_alive(struct adapter *padapter, u32 task)
 				rtw_set_rpwm(padapter, pslv);
 		}
 	}
-
-	mutex_unlock(&pwrctrl->lock);
 }
 
 /*
@@ -871,7 +864,7 @@ void rtw_unregister_tx_alive(struct adapter *padapter)
 			pslv = PS_STATE_S2;
 	}
 
-	mutex_lock(&pwrctrl->lock);
+	guard(mutex)(&pwrctrl->lock);
 
 	unregister_task_alive(pwrctrl, XMIT_ALIVE);
 
@@ -880,8 +873,6 @@ void rtw_unregister_tx_alive(struct adapter *padapter)
 			if ((pslv >= PS_STATE_S2) || (pwrctrl->alives == 0))
 				rtw_set_rpwm(padapter, pslv);
 	}
-
-	mutex_unlock(&pwrctrl->lock);
 }
 
 /*
@@ -907,7 +898,7 @@ void rtw_unregister_cmd_alive(struct adapter *padapter)
 			pslv = PS_STATE_S2;
 	}
 
-	mutex_lock(&pwrctrl->lock);
+	guard(mutex)(&pwrctrl->lock);
 
 	unregister_task_alive(pwrctrl, CMD_ALIVE);
 
@@ -917,8 +908,6 @@ void rtw_unregister_cmd_alive(struct adapter *padapter)
 				rtw_set_rpwm(padapter, pslv);
 		}
 	}
-
-	mutex_unlock(&pwrctrl->lock);
 }
 
 void rtw_init_pwrctrl_priv(struct adapter *padapter)
@@ -1108,9 +1097,8 @@ void rtw_ps_deny(struct adapter *padapter, enum ps_deny_reason reason)
 
 	pwrpriv = adapter_to_pwrctl(padapter);
 
-	mutex_lock(&pwrpriv->lock);
+	guard(mutex)(&pwrpriv->lock);
 	pwrpriv->ps_deny |= BIT(reason);
-	mutex_unlock(&pwrpriv->lock);
 }
 
 /*
@@ -1123,9 +1111,8 @@ void rtw_ps_deny_cancel(struct adapter *padapter, enum ps_deny_reason reason)
 
 	pwrpriv = adapter_to_pwrctl(padapter);
 
-	mutex_lock(&pwrpriv->lock);
+	guard(mutex)(&pwrpriv->lock);
 	pwrpriv->ps_deny &= ~BIT(reason);
-	mutex_unlock(&pwrpriv->lock);
 }
 
 /*
-- 
2.55.0