serial: omap: Fix missing pm_runtime_resume handling by simplifying code (d758c9c1) · Commits · 戴 / test

The lack of pm_runtime_resume handling for the device state leads into device wake-up interrupts not working after a while for runtime PM. Also, serial-omap is confused about the use of device_may_wakeup. The checks for device_may_wakeup should only be done for suspend and resume, not for pm_runtime_suspend and pm_runtime_resume. The wake-up events for PM runtime should always be enabled. The lack of pm_runtime_resume handling leads into device wake-up interrupts not working after a while for runtime PM. Rather than try to patch over the issue of adding complex tests to the pm_runtime_resume, let's fix the issues properly: 1. Make serial_omap_enable_wakeup deal with all internal PM state handling so we don't need to test for up->wakeups_enabled elsewhere. Later on once omap3 boots in device tree only mode we can also remove the up->wakeups_enabled flag and rely on the wake-up interrupt enable/disable state alone. 2. Do the device_may_wakeup checks in suspend and resume only, for runtime PM the wake-up events need to be always enabled. 3. Finally just call serial_omap_enable_wakeup and make sure we call it also in pm_runtime_resume. 4. Note that we also have to use disable_irq_nosync as serial_omap_irq calls pm_runtime_get_sync. Fixes: (serial: omap: Add support for optional wake-up) Cc: stable@vger.kernel.org # v3.13+ Signed-off-by:

Tony Lindgren <tony@atomide.com> Acked-by:

Felipe Balbi <balbi@ti.com> Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/omap-serial.c

+17 −12

Original line number	Diff line number	Diff line
		@@ -225,14 +225,19 @@ static inline void serial_omap_enable_wakeirq(struct uart_omap_port *up,
		if (enable)
		enable_irq(up->wakeirq);
		else
		disable_irq(up->wakeirq);
		disable_irq_nosync(up->wakeirq);
		}

		static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
		{
		struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);

		if (enable == up->wakeups_enabled)
		return;

		serial_omap_enable_wakeirq(up, enable);
		up->wakeups_enabled = enable;

		if (!pdata \|\| !pdata->enable_wakeup)
		return;

		@@ -1495,6 +1500,11 @@ static int serial_omap_suspend(struct device *dev)
		uart_suspend_port(&serial_omap_reg, &up->port);
		flush_work(&up->qos_work);

		if (device_may_wakeup(dev))
		serial_omap_enable_wakeup(up, true);
		else
		serial_omap_enable_wakeup(up, false);

		return 0;
		}

		@@ -1502,6 +1512,9 @@ static int serial_omap_resume(struct device *dev)
		{
		struct uart_omap_port *up = dev_get_drvdata(dev);

		if (device_may_wakeup(dev))
		serial_omap_enable_wakeup(up, false);

		uart_resume_port(&serial_omap_reg, &up->port);

		return 0;
		@@ -1878,17 +1891,7 @@ static int serial_omap_runtime_suspend(struct device *dev)

		up->context_loss_cnt = serial_omap_get_context_loss_count(up);

		if (device_may_wakeup(dev)) {
		if (!up->wakeups_enabled) {
		serial_omap_enable_wakeup(up, true);
		up->wakeups_enabled = true;
		}
		} else {
		if (up->wakeups_enabled) {
		serial_omap_enable_wakeup(up, false);
		up->wakeups_enabled = false;
		}
		}

		up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
		schedule_work(&up->qos_work);
		@@ -1902,6 +1905,8 @@ static int serial_omap_runtime_resume(struct device *dev)

		int loss_cnt = serial_omap_get_context_loss_count(up);

		serial_omap_enable_wakeup(up, false);

		if (loss_cnt < 0) {
		dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
		loss_cnt);

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