From d758c9c1b36b4d9a141c2146c70398d756167ed1 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Tue, 25 Mar 2014 11:48:47 -0700 Subject: [PATCH] serial: omap: Fix missing pm_runtime_resume handling by simplifying code 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: 2a0b965cfb6e (serial: omap: Add support for optional wake-up) Cc: stable@vger.kernel.org # v3.13+ Signed-off-by: Tony Lindgren Acked-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/omap-serial.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index ecfafbb30356..08b6b9419f0d 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -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; - } - } + serial_omap_enable_wakeup(up, true); 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); -- 2.20.1