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8250: remove unnecessary variable tmout from wait_for_xmitr()

PATCH In review Andre Haupt 2 participants 2 messages Dec 13, 2007

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Kernel janitors TTY layer and serial drivers
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Andre Haupt

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#0 lore raw

PATCH 1/1 8250: remove unnecessary variable tmout from wait_for_xmitr()

This fixes a sparse warning about symbol tmout shadowing an earlier one.

Signed-off-by Andre Haupt <[email protected]>
---
 drivers/serial/8250.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)
drivers/serial/8250.c +0 -1
index f94109c..284757d 100644
@@ -1727,7 +1727,6 @@ static inline void wait_for_xmitr(struct uart_8250_port *up, int bits)
 
 	/* Wait up to 1s for flow control if necessary */
 	if (up->port.flags & UPF_CONS_FLOW) {
-		unsigned int tmout;
 		for (tmout = 1000000; tmout; tmout--) {
 			unsigned int msr = serial_in(up, UART_MSR);
 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
Signature · 1 line
1.4.4.4
#1 lore raw

Hi,

Quoted 6 lines · Andre Haupt

This fixes a sparse warning about symbol tmout shadowing an earlier one.

Signed-off-by Andre Haupt <[email protected]>
---
 drivers/serial/8250.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

The whole timeout loops look somewhat odd. How about the following, totally untested, solution?

This converts the function to use more common timeout-loop constructs, gets rid of the shadowed variable and localises another variable even more! Hooray!

Hannes

Signed-off-by Johannes Weiner <[email protected]>

---

 drivers/serial/8250.c |   18 +++++++++---------
 1 files changed, 9 insertions(+), 9 deletions(-)
drivers/serial/8250.c +9 -9
index f94109c..7215f6a 100644
@@ -1712,30 +1712,30 @@ static void serial8250_break_ctl(struct uart_port *port, int break_state)
  */
 static inline void wait_for_xmitr(struct uart_8250_port *up, int bits)
 {
-	unsigned int status, tmout = 10000;
+	unsigned int tmout;
 
 	/* Wait up to 10ms for the character(s) to be sent. */
+	tmout = jiffies + jiffies_to_msecs(10);
 	do {
-		status = serial_in(up, UART_LSR);
+		unsigned int status = serial_in(up, UART_LSR);
 
-		up->lsr_saved_flags |= status & LSR_SAVE_FLAGS;
-
-		if (--tmout = 0)
+		up->lsr_saved_flags |= (status & LSR_SAVE_FLAGS);
+		if ((status & bits) = bits)
 			break;
 		udelay(1);
-	} while ((status & bits) != bits);
+	} while (time_after_eq(tmout, jiffies));
 
 	/* Wait up to 1s for flow control if necessary */
 	if (up->port.flags & UPF_CONS_FLOW) {
-		unsigned int tmout;
-		for (tmout = 1000000; tmout; tmout--) {
+		tmout = jiffies + jiffies_to_msecs(1000);
+		do {
 			unsigned int msr = serial_in(up, UART_MSR);
 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
 			if (msr & UART_MSR_CTS)
 				break;
 			udelay(1);
 			touch_nmi_watchdog();
-		}
+		} while (time_after_eq(tmout, jiffies));
 	}
 }