- Add a uart_rxready() and corresponding device-specific implementations

  that can be used to check whether receive data is ready, i.e. whether
  the subsequent call of uart_poll() should return a char, and unlike
  uart_poll() doesn't actually receive data.
- Remove the device-specific implementations of uart_poll() and implement
  uart_poll() in terms of uart_getc() and the newly added uart_rxready()
  in order to minimize code duplication.
- In sunkbd(4) take advantage of uart_rxready() and use it to implement
  the polled mode part of sunkbd_check() so we don't need to buffer a
  potentially read char in the softc.
- Fix some mis-indentation in sunkbd_read_char().

Discussed with:	marcel

1 files changed, 4 insertions, 6 deletions

diff --git a/sys/dev/uart/uart_dev_z8530.c b/sys/dev/uart/uart_dev_z8530.c
index 04ebc69..8509718 100644
--- a/sys/dev/uart/uart_dev_z8530.c
+++ b/sys/dev/uart/uart_dev_z8530.c
@@ -192,7 +192,7 @@ static int z8530_probe(struct uart_bas *bas);
 static void z8530_init(struct uart_bas *bas, int, int, int, int);
 static void z8530_term(struct uart_bas *bas);
 static void z8530_putc(struct uart_bas *bas, int);
-static int z8530_poll(struct uart_bas *bas);
+static int z8530_rxready(struct uart_bas *bas);
 static int z8530_getc(struct uart_bas *bas, struct mtx *);
 
 struct uart_ops uart_z8530_ops = {
@@ -200,7 +200,7 @@ struct uart_ops uart_z8530_ops = {
 	.init = z8530_init,
 	.term = z8530_term,
 	.putc = z8530_putc,
-	.poll = z8530_poll,
+	.rxready = z8530_rxready,
 	.getc = z8530_getc,
 };
 
@@ -235,12 +235,10 @@ z8530_putc(struct uart_bas *bas, int c)
 }
 
 static int
-z8530_poll(struct uart_bas *bas)
+z8530_rxready(struct uart_bas *bas)
 {
 
-	if (!(uart_getreg(bas, REG_CTRL) & BES_RXA))
-		return (-1);
-	return (uart_getreg(bas, REG_DATA));
+	return ((uart_getreg(bas, REG_CTRL) & BES_RXA) != 0 ? 1 : 0);
 }
 
 static int