[PATCH v5 13/15] OMAP2+: UART: Take console_lock in suspend path if not taken
Govindraj.R
govindraj.raja at ti.com
Wed Sep 21 08:13:50 EDT 2011
In suspend path the console_lock is taken by uart_port_suspend
however when no_console_suspend is used console_lock is not taken.
During system wide suspend omap_pwr_domain hooks cut all
clocks that are left enabled. So its unsafe to proceed printing after
clocks are cut by pwr_domain hooks. Also pm_runtime will be disabled after
dpm_suspend devices happens. So buffer all prints in suspend path by taking
console_lock and print them back safely after power domain hooks re-enable
clocks back.
Use CONFIG_SERIAL_OMAP_CONSOLE macro check to take console_lock since
console ops are available only if omap console is defined.
omap-serial can be built as module without console support.
Signed-off-by: Govindraj.R <govindraj.raja at ti.com>
---
arch/arm/plat-omap/include/plat/omap-serial.h | 1 +
drivers/tty/serial/omap-serial.c | 20 ++++++++++++++++++--
2 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h
index 28abc6b..de8de87 100644
--- a/arch/arm/plat-omap/include/plat/omap-serial.h
+++ b/arch/arm/plat-omap/include/plat/omap-serial.h
@@ -126,6 +126,7 @@ struct uart_omap_port {
u32 context_loss_cnt;
u8 wakeups_enabled;
u32 errata;
+ u8 console_locked;
};
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 64e4ab5..92a1f10 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -1133,8 +1133,15 @@ static int serial_omap_suspend(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
- if (up)
+ if (up) {
uart_suspend_port(&serial_omap_reg, &up->port);
+#ifdef CONFIG_SERIAL_OMAP_CONSOLE
+ if (up->port.line == up->port.cons->index &&
+ !is_console_locked())
+ up->console_locked = console_trylock();
+#endif
+ }
+
return 0;
}
@@ -1142,8 +1149,17 @@ static int serial_omap_resume(struct device *dev)
{
struct uart_omap_port *up = dev_get_drvdata(dev);
- if (up)
+ if (up) {
uart_resume_port(&serial_omap_reg, &up->port);
+#ifdef CONFIG_SERIAL_OMAP_CONSOLE
+ if (up->port.line == up->port.cons->index &&
+ up->console_locked) {
+ console_unlock();
+ up->console_locked = 0;
+ }
+#endif
+ }
+
return 0;
}
--
1.7.4.1
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