tty: serial: samsung: add byte-order aware bit functions

This driver makes use of the __set_bit() and __clear_bit() functions.
When running under big-endian, these functions don't convert the bit
indexes when working with peripheral registers, leading to the
incorrect bits being set and cleared when running big-endian.

Add two new driver functions for setting and clearing bits that are
byte-order aware.

Signed-off-by: Matthew Leach <matthew@mattleach.net>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 4d2924f61e0ba8c3f3db7b486454656f1822de61..ae2095a66708e0b06bf05bfe38d4a0901b158d3d 100644 (file)
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -169,8 +169,7 @@ static void s3c24xx_serial_stop_tx(struct uart_port *port)
                return;
 
        if (s3c24xx_serial_has_interrupt_mask(port))
-               __set_bit(S3C64XX_UINTM_TXD,
-                       portaddrl(port, S3C64XX_UINTM));
+               s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
        else
                disable_irq_nosync(ourport->tx_irq);
 
@@ -235,8 +234,7 @@ static void enable_tx_dma(struct s3c24xx_uart_port *ourport)
 
        /* Mask Tx interrupt */
        if (s3c24xx_serial_has_interrupt_mask(port))
-               __set_bit(S3C64XX_UINTM_TXD,
-                         portaddrl(port, S3C64XX_UINTM));
+               s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
        else
                disable_irq_nosync(ourport->tx_irq);
 
@@ -269,8 +267,8 @@ static void enable_tx_pio(struct s3c24xx_uart_port *ourport)
 
        /* Unmask Tx interrupt */
        if (s3c24xx_serial_has_interrupt_mask(port))
-               __clear_bit(S3C64XX_UINTM_TXD,
-                           portaddrl(port, S3C64XX_UINTM));
+               s3c24xx_clear_bit(port, S3C64XX_UINTM_TXD,
+                                 S3C64XX_UINTM);
        else
                enable_irq(ourport->tx_irq);
 
@@ -397,8 +395,8 @@ static void s3c24xx_serial_stop_rx(struct uart_port *port)
        if (rx_enabled(port)) {
                dbg("s3c24xx_serial_stop_rx: port=%p\n", port);
                if (s3c24xx_serial_has_interrupt_mask(port))
-                       __set_bit(S3C64XX_UINTM_RXD,
-                               portaddrl(port, S3C64XX_UINTM));
+                       s3c24xx_set_bit(port, S3C64XX_UINTM_RXD,
+                                       S3C64XX_UINTM);
                else
                        disable_irq_nosync(ourport->rx_irq);
                rx_enabled(port) = 0;
@@ -1069,7 +1067,7 @@ static int s3c64xx_serial_startup(struct uart_port *port)
        spin_unlock_irqrestore(&port->lock, flags);
 
        /* Enable Rx Interrupt */
-       __clear_bit(S3C64XX_UINTM_RXD, portaddrl(port, S3C64XX_UINTM));
+       s3c24xx_clear_bit(port, S3C64XX_UINTM_RXD, S3C64XX_UINTM);
 
        dbg("s3c64xx_serial_startup ok\n");
        return ret;

diff --git a/drivers/tty/serial/samsung.h b/drivers/tty/serial/samsung.h
index 8f96b715a7b0ec733e026930133625468570554a..2ae4fcee181458ce008c499b266e1e7ecd3d614f 100644 (file)
--- a/drivers/tty/serial/samsung.h
+++ b/drivers/tty/serial/samsung.h
@@ -123,4 +123,32 @@ struct s3c24xx_uart_port {
 #define wr_regb(port, reg, val) writeb_relaxed(val, portaddr(port, reg))
 #define wr_regl(port, reg, val) writel_relaxed(val, portaddr(port, reg))
 
+/* Byte-order aware bit setting/clearing functions. */
+
+static inline void s3c24xx_set_bit(struct uart_port *port, int idx,
+                                  unsigned int reg)
+{
+       unsigned long flags;
+       u32 val;
+
+       local_irq_save(flags);
+       val = rd_regl(port, reg);
+       val |= (1 << idx);
+       wr_regl(port, reg, val);
+       local_irq_restore(flags);
+}
+
+static inline void s3c24xx_clear_bit(struct uart_port *port, int idx,
+                                    unsigned int reg)
+{
+       unsigned long flags;
+       u32 val;
+
+       local_irq_save(flags);
+       val = rd_regl(port, reg);
+       val &= ~(1 << idx);
+       wr_regl(port, reg, val);
+       local_irq_restore(flags);
+}
+
 #endif