[PATCH 5/6] serial: 8250_omap: Require a valid wakeirq for deeper idle states
From: Tony Lindgren <tony@atomide.com>
Date: 2021-09-21 10:34:13
Also in:
linux-omap, lkml
Subsystem:
8250/16?50 (and clone uarts) serial driver, the rest, tty layer and serial drivers · Maintainers:
Greg Kroah-Hartman, Linus Torvalds, Jiri Slaby
For deeper idle states the 8250 device gets powered off. The wakeup is handled with a separate wakeirq controller monitoring the RX pin. Let's check for a valid wakeirq before enabling deeper idle states. Signed-off-by: Tony Lindgren <tony@atomide.com> --- drivers/tty/serial/8250/8250_omap.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c@@ -133,6 +133,7 @@ struct omap8250_priv { spinlock_t rx_dma_lock; bool rx_dma_broken; bool throttled; + unsigned int allow_rpm:1; }; struct omap8250_dma_params {
@@ -676,6 +677,7 @@ static int omap_8250_startup(struct uart_port *port) ret = dev_pm_set_dedicated_wake_irq(port->dev, priv->wakeirq); if (ret) return ret; + priv->allow_rpm = 1; } pm_runtime_get_sync(port->dev);
@@ -722,6 +724,10 @@ static int omap_8250_startup(struct uart_port *port) if (up->dma && !(priv->habit & UART_HAS_EFR2)) up->dma->rx_dma(up); + /* Block runtime PM if no wakeirq, paired with shutdown */ + if (!priv->allow_rpm) + pm_runtime_get(port->dev); + pm_runtime_mark_last_busy(port->dev); pm_runtime_put_autosuspend(port->dev); return 0;
@@ -760,6 +766,10 @@ static void omap_8250_shutdown(struct uart_port *port) serial_out(up, UART_LCR, up->lcr & ~UART_LCR_SBC); serial_out(up, UART_FCR, UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT); + /* Clear possible PM runtime block to pair with startup */ + if (!priv->allow_rpm) + pm_runtime_put(port->dev); + pm_runtime_mark_last_busy(port->dev); pm_runtime_put_autosuspend(port->dev); free_irq(port->irq, port);
--
2.33.0