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>

1 files changed, 28 insertions, 0 deletions

diff --git a/drivers/tty/serial/samsung.h b/drivers/tty/serial/samsung.h
index 8f96b715a7b0..2ae4fcee1814 100644
--- 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