lkml.org 
[lkml]   [2019]   [Jun]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 06/10] serial: stm32: add support for no_console_suspend
Date
In order to display console messages in low power mode, console pins
must be kept active after suspend call.

Signed-off-by: Bich Hemon <bich.hemon@st.com>
Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c
index 0d43711..00e4d7a 100644
--- a/drivers/tty/serial/stm32-usart.c
+++ b/drivers/tty/serial/stm32-usart.c
@@ -24,6 +24,8 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/pinctrl/devinfo.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/pm_wakeirq.h>
@@ -846,6 +848,7 @@ static int stm32_init_port(struct stm32_port *stm32port,
{
struct uart_port *port = &stm32port->port;
struct resource *res;
+ struct pinctrl *uart_pinctrl;
int ret;

port->iotype = UPIO_MEM;
@@ -879,6 +882,24 @@ static int stm32_init_port(struct stm32_port *stm32port,

stm32port->fifoen = stm32port->info->cfg.has_fifo;

+ uart_pinctrl = devm_pinctrl_get(&pdev->dev);
+ if (IS_ERR(uart_pinctrl)) {
+ ret = PTR_ERR(uart_pinctrl);
+ if (ret != -ENODEV) {
+ dev_err(&pdev->dev, "Can't get pinctrl, error %d\n",
+ ret);
+ return ret;
+ }
+ stm32port->console_pins = ERR_PTR(-ENODEV);
+ } else {
+ stm32port->console_pins = pinctrl_lookup_state
+ (uart_pinctrl, "no_console_suspend");
+ }
+
+ if (IS_ERR(stm32port->console_pins) && PTR_ERR(stm32port->console_pins)
+ != -ENODEV)
+ return PTR_ERR(stm32port->console_pins);
+
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
port->membase = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(port->membase))
@@ -1303,6 +1324,7 @@ static void __maybe_unused stm32_serial_enable_wakeup(struct uart_port *port,
static int __maybe_unused stm32_serial_suspend(struct device *dev)
{
struct uart_port *port = dev_get_drvdata(dev);
+ struct stm32_port *stm32_port = to_stm32_port(port);

uart_suspend_port(&stm32_usart_driver, port);

@@ -1311,7 +1333,19 @@ static int __maybe_unused stm32_serial_suspend(struct device *dev)
else
stm32_serial_enable_wakeup(port, false);

- pinctrl_pm_select_sleep_state(dev);
+ if (uart_console(port) && !console_suspend_enabled) {
+ if (IS_ERR(stm32_port->console_pins)) {
+ dev_err(dev, "no_console_suspend pinctrl not found\n");
+ return PTR_ERR(stm32_port->console_pins);
+ }
+
+ pinctrl_select_state(dev->pins->p, stm32_port->console_pins);
+ } else {
+ if (device_may_wakeup(dev))
+ pinctrl_pm_select_idle_state(dev);
+ else
+ pinctrl_pm_select_sleep_state(dev);
+ }

return 0;
}
diff --git a/drivers/tty/serial/stm32-usart.h b/drivers/tty/serial/stm32-usart.h
index 30d2433..050fe04 100644
--- a/drivers/tty/serial/stm32-usart.h
+++ b/drivers/tty/serial/stm32-usart.h
@@ -255,6 +255,7 @@ struct stm32_port {
bool fifoen;
int wakeirq;
int rdr_mask; /* receive data register mask */
+ struct pinctrl_state *console_pins;
};

static struct stm32_port stm32_ports[STM32_MAX_PORTS];
--
1.9.1
\
 
 \ /
  Last update: 2019-06-11 14:27    [W:0.074 / U:1.700 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site