[PATCH v2 3/9] tty: serial: fsl_lpuart: support suspend/resume

[Bhuvanchandra DV]

From: Stefan Agner <ste...@agner.ch>

Add suspend/resume support.

Signed-off-by: Stefan Agner <ste...@agner.ch>
Signed-off-by: Bhuvanchandra DV <bhuvanchandra...@toradex.com>
---
 drivers/tty/serial/fsl_lpuart.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index fabfa7e..75a2098 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -483,9 +483,8 @@ static void lpuart_dma_rx_complete(void *arg)
        spin_unlock_irqrestore(&sport->port.lock, flags);
 }
 
-static void lpuart_timer_func(unsigned long data)
+static void lpuart_dma_rx_terminate(struct lpuart_port *sport)
 {
-       struct lpuart_port *sport = (struct lpuart_port *)data;
        struct tty_port *port = &sport->port.state->port;
        struct dma_tx_state state;
        unsigned long flags;
@@ -510,6 +509,11 @@ static void lpuart_timer_func(unsigned long data)
        spin_unlock_irqrestore(&sport->port.lock, flags);
 }
 
+static void lpuart_timer_func(unsigned long data)
+{
+       lpuart_dma_rx_terminate((struct lpuart_port *)data);
+}
+
 static inline void lpuart_prepare_rx(struct lpuart_port *sport)
 {
        unsigned long flags;
@@ -1925,7 +1929,12 @@ static int lpuart_suspend(struct device *dev)
                writeb(temp, sport->port.membase + UARTCR2);
        }
 
+       if (sport->dma_rx_in_progress)
+               lpuart_dma_rx_terminate(sport);
+
        uart_suspend_port(&lpuart_reg, &sport->port);
+       if (sport->port.suspended && !sport->port.irq_wake)
+               clk_disable_unprepare(sport->clk);
 
        return 0;
 }
@@ -1935,6 +1944,9 @@ static int lpuart_resume(struct device *dev)
        struct lpuart_port *sport = dev_get_drvdata(dev);
        unsigned long temp;
 
+       if (sport->port.suspended && !sport->port.irq_wake)
+               clk_prepare_enable(sport->clk);
+
        if (sport->lpuart32) {
                lpuart32_setup_watermark(sport);
                temp = lpuart32_read(sport->port.membase + UARTCTRL);
-- 
2.9.0