tty: xuartps: Refactor read-modify-writes

A lot of read-modify-write sequences used a one-line statement which
nests a readl() within a writel(). Convert this into code sequences that
make the three steps more obvious.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 814391038abb4b05fe35eb3ac8710fd96b9757ca..b182ab8cfd0774a9e4ebad418a34eece3c8d3203 100644 (file)
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -437,9 +437,9 @@ static int xuartps_clk_notifier_cb(struct notifier_block *nb,
                spin_lock_irqsave(&xuartps->port->lock, flags);
 
                /* Disable the TX and RX to set baud rate */
-               xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) |
-                               (XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS),
-                               XUARTPS_CR_OFFSET);
+               ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
+               ctrl_reg |= XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS;
+               xuartps_writel(ctrl_reg, XUARTPS_CR_OFFSET);
 
                spin_unlock_irqrestore(&xuartps->port->lock, flags);
 
@@ -464,9 +464,9 @@ static int xuartps_clk_notifier_cb(struct notifier_block *nb,
                        spin_lock_irqsave(&xuartps->port->lock, flags);
 
                /* Set TX/RX Reset */
-               xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) |
-                               (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST),
-                               XUARTPS_CR_OFFSET);
+               ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
+               ctrl_reg |= XUARTPS_CR_TXRST | XUARTPS_CR_RXRST;
+               xuartps_writel(ctrl_reg, XUARTPS_CR_OFFSET);
 
                while (xuartps_readl(XUARTPS_CR_OFFSET) &
                                (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST))
@@ -479,10 +479,9 @@ static int xuartps_clk_notifier_cb(struct notifier_block *nb,
                 */
                xuartps_writel(rx_timeout, XUARTPS_RXTOUT_OFFSET);
                ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
-               xuartps_writel(
-                       (ctrl_reg & ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS)) |
-                       (XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN),
-                       XUARTPS_CR_OFFSET);
+               ctrl_reg &= ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS);
+               ctrl_reg |= XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN;
+               xuartps_writel(ctrl_reg, XUARTPS_CR_OFFSET);
 
                spin_unlock_irqrestore(&xuartps->port->lock, flags);
 
@@ -631,9 +630,9 @@ static void xuartps_set_termios(struct uart_port *port,
        }
 
        /* Disable the TX and RX to set baud rate */
-       xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) |
-                       (XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS),
-                       XUARTPS_CR_OFFSET);
+       ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
+       ctrl_reg |= XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS;
+       xuartps_writel(ctrl_reg, XUARTPS_CR_OFFSET);
 
        /*
         * Min baud rate = 6bps and Max Baud Rate is 10Mbps for 100Mhz clk
@@ -651,20 +650,18 @@ static void xuartps_set_termios(struct uart_port *port,
        uart_update_timeout(port, termios->c_cflag, baud);
 
        /* Set TX/RX Reset */
-       xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) |
-                       (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST),
-                       XUARTPS_CR_OFFSET);
-
        ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
+       ctrl_reg |= XUARTPS_CR_TXRST | XUARTPS_CR_RXRST;
+       xuartps_writel(ctrl_reg, XUARTPS_CR_OFFSET);
 
        /*
         * Clear the RX disable and TX disable bits and then set the TX enable
         * bit and RX enable bit to enable the transmitter and receiver.
         */
-       xuartps_writel(
-               (ctrl_reg & ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS))
-                       | (XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN),
-                       XUARTPS_CR_OFFSET);
+       ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
+       ctrl_reg &= ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS);
+       ctrl_reg |= XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN;
+       xuartps_writel(ctrl_reg, XUARTPS_CR_OFFSET);
 
        xuartps_writel(rx_timeout, XUARTPS_RXTOUT_OFFSET);
 
@@ -1248,9 +1245,9 @@ static int xuartps_resume(struct device *device)
                spin_lock_irqsave(&port->lock, flags);
 
                /* Set TX/RX Reset */
-               xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) |
-                               (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST),
-                               XUARTPS_CR_OFFSET);
+               ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
+               ctrl_reg |= XUARTPS_CR_TXRST | XUARTPS_CR_RXRST;
+               xuartps_writel(ctrl_reg, XUARTPS_CR_OFFSET);
                while (xuartps_readl(XUARTPS_CR_OFFSET) &
                                (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST))
                        cpu_relax();
@@ -1259,10 +1256,9 @@ static int xuartps_resume(struct device *device)
                xuartps_writel(rx_timeout, XUARTPS_RXTOUT_OFFSET);
                /* Enable Tx/Rx */
                ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET);
-               xuartps_writel(
-                       (ctrl_reg & ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS)) |
-                       (XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN),
-                       XUARTPS_CR_OFFSET);
+               ctrl_reg &= ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS);
+               ctrl_reg |= XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN;
+               xuartps_writel(ctrl_reg, XUARTPS_CR_OFFSET);
 
                spin_unlock_irqrestore(&port->lock, flags);
        } else {