tty: serial: samsung_tty: remove spinlock flags in interrupt handlers
authorKrzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Mon, 15 Mar 2021 18:12:12 +0000 (19:12 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 23 Mar 2021 09:20:38 +0000 (10:20 +0100)
Since interrupt handler is called with disabled local interrupts, there
is no need to use the spinlock primitives disabling interrupts as well.

Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210315181212.113217-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/serial/samsung_tty.c

index 80df842..d9e4b67 100644 (file)
@@ -715,13 +715,12 @@ static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id)
        struct s3c24xx_uart_dma *dma = ourport->dma;
        struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
        struct tty_port *t = &port->state->port;
-       unsigned long flags;
        struct dma_tx_state state;
 
        utrstat = rd_regl(port, S3C2410_UTRSTAT);
        rd_regl(port, S3C2410_UFSTAT);
 
-       spin_lock_irqsave(&port->lock, flags);
+       spin_lock(&port->lock);
 
        if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) {
                s3c64xx_start_rx_dma(ourport);
@@ -750,7 +749,7 @@ static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id)
        wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT);
 
 finish:
-       spin_unlock_irqrestore(&port->lock, flags);
+       spin_unlock(&port->lock);
 
        return IRQ_HANDLED;
 }
@@ -846,11 +845,10 @@ static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id)
 {
        struct s3c24xx_uart_port *ourport = dev_id;
        struct uart_port *port = &ourport->port;
-       unsigned long flags;
 
-       spin_lock_irqsave(&port->lock, flags);
+       spin_lock(&port->lock);
        s3c24xx_serial_rx_drain_fifo(ourport);
-       spin_unlock_irqrestore(&port->lock, flags);
+       spin_unlock(&port->lock);
 
        return IRQ_HANDLED;
 }
@@ -934,13 +932,12 @@ static irqreturn_t s3c24xx_serial_tx_irq(int irq, void *id)
 {
        struct s3c24xx_uart_port *ourport = id;
        struct uart_port *port = &ourport->port;
-       unsigned long flags;
 
-       spin_lock_irqsave(&port->lock, flags);
+       spin_lock(&port->lock);
 
        s3c24xx_serial_tx_chars(ourport);
 
-       spin_unlock_irqrestore(&port->lock, flags);
+       spin_unlock(&port->lock);
        return IRQ_HANDLED;
 }