serial: sc16is7xx: use guards for simple mutex locks

Guards can help to make the code more readable, so use them wherever they
do so.

In sc16is7xx_port_irq(), labels and 'rc' locals are eliminated completely.

Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://patch.msgid.link/20251027142957.1032073-6-hugo@hugovil.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 335695d0e7aa7919ed39988fd50f29c26de5fd06..1acf5be03d489ac5240a6079191c1e0ebb7a101a 100644 (file)
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -11,6 +11,7 @@
 #define DEFAULT_SYMBOL_NAMESPACE "SERIAL_NXP_SC16IS7XX"
 
 #include <linux/bits.h>
+#include <linux/cleanup.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/device.h>
@@ -778,18 +779,15 @@ static void sc16is7xx_update_mlines(struct sc16is7xx_one *one)
 
 static bool sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
 {
-       bool rc = true;
        unsigned int iir, rxlen;
        struct uart_port *port = &s->p[portno].port;
        struct sc16is7xx_one *one = to_sc16is7xx_one(port, port);
 
-       mutex_lock(&one->lock);
+       guard(mutex)(&one->lock);
 
        iir = sc16is7xx_port_read(port, SC16IS7XX_IIR_REG);
-       if (iir & SC16IS7XX_IIR_NO_INT_BIT) {
-               rc = false;
-               goto out_port_irq;
-       }
+       if (iir & SC16IS7XX_IIR_NO_INT_BIT)
+               return false;
 
        iir &= SC16IS7XX_IIR_ID_MASK;
 
@@ -829,10 +827,7 @@ static bool sc16is7xx_port_irq(struct sc16is7xx_port *s, int portno)
                break;
        }
 
-out_port_irq:
-       mutex_unlock(&one->lock);
-
-       return rc;
+       return true;
 }
 
 static irqreturn_t sc16is7xx_irq(int irq, void *dev_id)
@@ -873,9 +868,8 @@ static void sc16is7xx_tx_proc(struct kthread_work *ws)
            (port->rs485.delay_rts_before_send > 0))
                msleep(port->rs485.delay_rts_before_send);
 
-       mutex_lock(&one->lock);
+       guard(mutex)(&one->lock);
        sc16is7xx_handle_tx(port);
-       mutex_unlock(&one->lock);
 }
 
 static void sc16is7xx_reconf_rs485(struct uart_port *port)
@@ -942,9 +936,8 @@ static void sc16is7xx_ms_proc(struct kthread_work *ws)
        struct sc16is7xx_port *s = dev_get_drvdata(one->port.dev);
 
        if (one->port.state) {
-               mutex_lock(&one->lock);
-               sc16is7xx_update_mlines(one);
-               mutex_unlock(&one->lock);
+               scoped_guard(mutex, &one->lock)
+                       sc16is7xx_update_mlines(one);
 
                kthread_queue_delayed_work(&s->kworker, &one->ms_work, HZ);
        }