[PATCH 2/5] serial: sprd: Use readable macros instead of magic number

From: Baolin Wang
Date: Fri Aug 10 2018 - 21:35:15 EST


Define readable macros instead of magic number to make code more readable.

Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
---
drivers/tty/serial/sprd_serial.c | 25 +++++++++++++++++--------
1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c
index 1b0e3fb..e18d8af 100644
--- a/drivers/tty/serial/sprd_serial.c
+++ b/drivers/tty/serial/sprd_serial.c
@@ -45,6 +45,8 @@

/* data number in TX and RX fifo */
#define SPRD_STS1 0x000C
+#define SPRD_RX_FIFO_CNT_MASK GENMASK(7, 0)
+#define SPRD_TX_FIFO_CNT_MASK GENMASK(15, 8)

/* interrupt enable register and its BITs */
#define SPRD_IEN 0x0010
@@ -82,11 +84,15 @@
/* fifo threshold register */
#define SPRD_CTL2 0x0020
#define THLD_TX_EMPTY 0x40
+#define THLD_TX_EMPTY_SHIFT 8
#define THLD_RX_FULL 0x40

/* config baud rate register */
#define SPRD_CLKD0 0x0024
+#define SPRD_CLKD0_MASK GENMASK(15, 0)
#define SPRD_CLKD1 0x0028
+#define SPRD_CLKD1_MASK GENMASK(20, 16)
+#define SPRD_CLKD1_SHIFT 16

/* interrupt mask status register */
#define SPRD_IMSR 0x002C
@@ -115,7 +121,7 @@ static inline void serial_out(struct uart_port *port, int offset, int value)

static unsigned int sprd_tx_empty(struct uart_port *port)
{
- if (serial_in(port, SPRD_STS1) & 0xff00)
+ if (serial_in(port, SPRD_STS1) & SPRD_TX_FIFO_CNT_MASK)
return 0;
else
return TIOCSER_TEMT;
@@ -213,7 +219,8 @@ static inline void sprd_rx(struct uart_port *port)
struct tty_port *tty = &port->state->port;
unsigned int ch, flag, lsr, max_count = SPRD_TIMEOUT;

- while ((serial_in(port, SPRD_STS1) & 0x00ff) && max_count--) {
+ while ((serial_in(port, SPRD_STS1) & SPRD_RX_FIFO_CNT_MASK) &&
+ max_count--) {
lsr = serial_in(port, SPRD_LSR);
ch = serial_in(port, SPRD_RXD);
flag = TTY_NORMAL;
@@ -303,16 +310,17 @@ static int sprd_startup(struct uart_port *port)
struct sprd_uart_port *sp;
unsigned long flags;

- serial_out(port, SPRD_CTL2, ((THLD_TX_EMPTY << 8) | THLD_RX_FULL));
+ serial_out(port, SPRD_CTL2,
+ THLD_TX_EMPTY << THLD_TX_EMPTY_SHIFT | THLD_RX_FULL);

/* clear rx fifo */
timeout = SPRD_TIMEOUT;
- while (timeout-- && serial_in(port, SPRD_STS1) & 0x00ff)
+ while (timeout-- && serial_in(port, SPRD_STS1) & SPRD_RX_FIFO_CNT_MASK)
serial_in(port, SPRD_RXD);

/* clear tx fifo */
timeout = SPRD_TIMEOUT;
- while (timeout-- && serial_in(port, SPRD_STS1) & 0xff00)
+ while (timeout-- && serial_in(port, SPRD_STS1) & SPRD_TX_FIFO_CNT_MASK)
cpu_relax();

/* clear interrupt */
@@ -433,10 +441,11 @@ static void sprd_set_termios(struct uart_port *port,
}

/* clock divider bit0~bit15 */
- serial_out(port, SPRD_CLKD0, quot & 0xffff);
+ serial_out(port, SPRD_CLKD0, quot & SPRD_CLKD0_MASK);

/* clock divider bit16~bit20 */
- serial_out(port, SPRD_CLKD1, (quot & 0x1f0000) >> 16);
+ serial_out(port, SPRD_CLKD1,
+ (quot & SPRD_CLKD1_MASK) >> SPRD_CLKD1_SHIFT);
serial_out(port, SPRD_LCR, lcr);
fc |= RX_TOUT_THLD_DEF | RX_HFC_THLD_DEF;
serial_out(port, SPRD_CTL1, fc);
@@ -510,7 +519,7 @@ static void wait_for_xmitr(struct uart_port *port)
if (--tmout == 0)
break;
udelay(1);
- } while (status & 0xff00);
+ } while (status & SPRD_TX_FIFO_CNT_MASK);
}

static void sprd_console_putchar(struct uart_port *port, int ch)
--
1.9.1