serial: stm32: fix wakeup source initialization

Fixes dedicated_irq_wakeup issue and deactivated uart as wakeup source by
default.

Fixes: 270e5a7 ("serial: stm32: add wakeup mechanism")
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/stm32-usart.c

@@ -557,7 +557,6 @@ static int stm32_startup(struct uart_port *port)
 {
 	struct stm32_port *stm32_port = to_stm32_port(port);
 	struct stm32_usart_offsets *ofs = &stm32_port->info->ofs;
-	struct stm32_usart_config *cfg = &stm32_port->info->cfg;
 	const char *name = to_platform_device(port->dev)->name;
 	u32 val;
 	int ret;
@@ -568,15 +567,6 @@ static int stm32_startup(struct uart_port *port)
 	if (ret)
 		return ret;
 
-	if (cfg->has_wakeup && stm32_port->wakeirq >= 0) {
-		ret = dev_pm_set_dedicated_wake_irq(port->dev,
-						    stm32_port->wakeirq);
-		if (ret) {
-			free_irq(port->irq, port);
-			return ret;
-		}
-	}
-
 	val = USART_CR1_RXNEIE | USART_CR1_TE | USART_CR1_RE;
 	if (stm32_port->fifoen)
 		val |= USART_CR1_FIFOEN;
@@ -607,7 +597,6 @@ static void stm32_shutdown(struct uart_port *port)
 
 	stm32_clr_bits(port, ofs->cr1, val);
 
-	dev_pm_clear_wake_irq(port->dev);
 	free_irq(port->irq, port);
 }
 
@@ -1079,11 +1068,18 @@ static int stm32_serial_probe(struct platform_device *pdev)
 		ret = device_init_wakeup(&pdev->dev, true);
 		if (ret)
 			goto err_uninit;
+
+		ret = dev_pm_set_dedicated_wake_irq(&pdev->dev,
+						    stm32port->wakeirq);
+		if (ret)
+			goto err_nowup;
+
+		device_set_wakeup_enable(&pdev->dev, false);
 	}
 
 	ret = uart_add_one_port(&stm32_usart_driver, &stm32port->port);
 	if (ret)
-		goto err_nowup;
+		goto err_wirq;
 
 	ret = stm32_of_dma_rx_probe(stm32port, pdev);
 	if (ret)
@@ -1097,6 +1093,10 @@ static int stm32_serial_probe(struct platform_device *pdev)
 
 	return 0;
 
+err_wirq:
+	if (stm32port->info->cfg.has_wakeup && stm32port->wakeirq >= 0)
+		dev_pm_clear_wake_irq(&pdev->dev);
+
 err_nowup:
 	if (stm32port->info->cfg.has_wakeup && stm32port->wakeirq >= 0)
 		device_init_wakeup(&pdev->dev, false);
@@ -1134,8 +1134,10 @@ static int stm32_serial_remove(struct platform_device *pdev)
 				  TX_BUF_L, stm32_port->tx_buf,
 				  stm32_port->tx_dma_buf);
 
-	if (cfg->has_wakeup && stm32_port->wakeirq >= 0)
+	if (cfg->has_wakeup && stm32_port->wakeirq >= 0) {
+		dev_pm_clear_wake_irq(&pdev->dev);
 		device_init_wakeup(&pdev->dev, false);
+	}
 
 	clk_disable_unprepare(stm32_port->clk);