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authorLinus Torvalds <torvalds@linux-foundation.org>2008-04-18 08:37:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-04-18 08:37:01 -0700
commit9732b6112343df2872518ec6701c8ef729310a05 (patch)
tree9e3dcc461845038da4730c2062eee546348ca445 /drivers/serial/8250.c
parent9e9abecfc0ff3a9ad2ead954b37bbfcb863c775e (diff)
parent1a9a3e76dde191f82f7a8a66059dcbb4a9f63ff3 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-kgdb
* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-kgdb: kgdb: always use icache flush for sw breakpoints kgdb: fix SMP NMI kgdb_handle_exception exit race kgdb: documentation fixes kgdb: allow static kgdbts boot configuration kgdb: add documentation kgdb: Kconfig fix kgdb: add kgdb internal test suite kgdb: fix several kgdb regressions kgdb: kgdboc pl011 I/O module kgdb: fix optional arch functions and probe_kernel_* kgdb: add x86 HW breakpoints kgdb: print breakpoint removed on exception kgdb: clocksource watchdog kgdb: fix NMI hangs kgdb: fix kgdboc dynamic module configuration kgdb: document parameters x86: kgdb support consoles: polling support, kgdboc kgdb: core uaccess: add probe_kernel_write()
Diffstat (limited to 'drivers/serial/8250.c')
-rw-r--r--drivers/serial/8250.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 77f7a7f0646..96a585e1cee 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -1740,6 +1740,60 @@ static inline void wait_for_xmitr(struct uart_8250_port *up, int bits)
}
}
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * Console polling routines for writing and reading from the uart while
+ * in an interrupt or debug context.
+ */
+
+static int serial8250_get_poll_char(struct uart_port *port)
+{
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+ unsigned char lsr = serial_inp(up, UART_LSR);
+
+ while (!(lsr & UART_LSR_DR))
+ lsr = serial_inp(up, UART_LSR);
+
+ return serial_inp(up, UART_RX);
+}
+
+
+static void serial8250_put_poll_char(struct uart_port *port,
+ unsigned char c)
+{
+ unsigned int ier;
+ struct uart_8250_port *up = (struct uart_8250_port *)port;
+
+ /*
+ * First save the IER then disable the interrupts
+ */
+ ier = serial_in(up, UART_IER);
+ if (up->capabilities & UART_CAP_UUE)
+ serial_out(up, UART_IER, UART_IER_UUE);
+ else
+ serial_out(up, UART_IER, 0);
+
+ wait_for_xmitr(up, BOTH_EMPTY);
+ /*
+ * Send the character out.
+ * If a LF, also do CR...
+ */
+ serial_out(up, UART_TX, c);
+ if (c == 10) {
+ wait_for_xmitr(up, BOTH_EMPTY);
+ serial_out(up, UART_TX, 13);
+ }
+
+ /*
+ * Finally, wait for transmitter to become empty
+ * and restore the IER
+ */
+ wait_for_xmitr(up, BOTH_EMPTY);
+ serial_out(up, UART_IER, ier);
+}
+
+#endif /* CONFIG_CONSOLE_POLL */
+
static int serial8250_startup(struct uart_port *port)
{
struct uart_8250_port *up = (struct uart_8250_port *)port;
@@ -2386,6 +2440,10 @@ static struct uart_ops serial8250_pops = {
.request_port = serial8250_request_port,
.config_port = serial8250_config_port,
.verify_port = serial8250_verify_port,
+#ifdef CONFIG_CONSOLE_POLL
+ .poll_get_char = serial8250_get_poll_char,
+ .poll_put_char = serial8250_put_poll_char,
+#endif
};
static struct uart_8250_port serial8250_ports[UART_NR];