On some i.MX SoCs' low power mode, such as i.MX7D's LPSR(low power state retention), UART iomux settings will be lost, need to add pinctrl sleep/default mode switch during suspend/resume to make sure UART iomux settings are correct after resume. Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx> --- drivers/tty/serial/imx.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index c15332d..6ccb5c4 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -24,6 +24,7 @@ #include <linux/serial.h> #include <linux/clk.h> #include <linux/delay.h> +#include <linux/pinctrl/consumer.h> #include <linux/rational.h> #include <linux/slab.h> #include <linux/of.h> @@ -2449,6 +2450,8 @@ static int imx_uart_suspend_noirq(struct device *dev) clk_disable(sport->clk_ipg); + pinctrl_pm_select_sleep_state(dev); + return 0; } @@ -2457,6 +2460,8 @@ static int imx_uart_resume_noirq(struct device *dev) struct imx_port *sport = dev_get_drvdata(dev); int ret; + pinctrl_pm_select_default_state(dev); + ret = clk_enable(sport->clk_ipg); if (ret) return ret; -- 2.7.4
