[PATCH v2] serial: 8250-mtk: modify mtk uart power and clock management

From: Changqi Hu
Date: Thu Jul 18 2019 - 08:58:53 EST


modify mtk uart runtime interface, enable uart clock before register.

Signed-off-by: Changqi Hu <changqi.hu@xxxxxxxxxxxx>
---
drivers/tty/serial/8250/8250_mtk.c | 21 ++++++++-------------
1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
index b0113d1..a07c8ae 100644
--- a/drivers/tty/serial/8250/8250_mtk.c
+++ b/drivers/tty/serial/8250/8250_mtk.c
@@ -389,7 +389,7 @@ static int __maybe_unused mtk8250_runtime_suspend(struct device *dev)
struct mtk8250_data *data = dev_get_drvdata(dev);
struct uart_8250_port *up = serial8250_get_port(data->line);

- /*wait until UART in idle status*/
+ /* wait until UART in idle status */
while
(serial_in(up, MTK_UART_DEBUG0));

@@ -426,23 +426,15 @@ static int __maybe_unused mtk8250_runtime_resume(struct device *dev)
static void
mtk8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old)
{
- struct uart_8250_port *up = up_to_u8250p(port);
-
- if (!state) {
- if (!(up->capabilities & UART_CAP_RPM))
- mtk8250_runtime_resume(port->dev);
- else
+ if (!state)
+ if (!mtk8250_runtime_resume(port->dev))
pm_runtime_get_sync(port->dev);
- }

serial8250_do_pm(port, state, old);

- if (state) {
- if (!(up->capabilities & UART_CAP_RPM))
+ if (state)
+ if (!pm_runtime_put_sync_suspend(port->dev))
mtk8250_runtime_suspend(port->dev);
- else
- pm_runtime_put_sync_suspend(port->dev);
- }
}

#ifdef CONFIG_SERIAL_8250_DMA
@@ -554,6 +546,9 @@ static int mtk8250_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, data);

pm_runtime_enable(&pdev->dev);
+ err = mtk8250_runtime_resume(&pdev->dev);
+ if (err)
+ return err;

data->line = serial8250_register_8250_port(&uart);
if (data->line < 0)
--
1.8.1.1.dirty