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* [PATCH 0/2] tty: serial: imx: improve the imx uart wakeup function
@ 2025-09-23  3:16 Sherry Sun
  2025-09-23  3:16 ` [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source Sherry Sun
  2025-09-23  3:16 ` [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting Sherry Sun
  0 siblings, 2 replies; 8+ messages in thread
From: Sherry Sun @ 2025-09-23  3:16 UTC (permalink / raw)
  To: gregkh, jirislaby, shawnguo, s.hauer, kernel, festevam,
	shenwei.wang
  Cc: linux-serial, linux-kernel, imx

Make some improvements for imx uart wakeup function. The first patch adds
device_may_wakeup() check before configuring the wake related registers.
The second patch adds the wakeup event reporting support for imx uart.

Sherry Sun (2):
  tty: serial: imx: Only configure the wake register when device is set
    as wakeup source
  tty: serial: imx: Add missing wakeup event reporting

 drivers/tty/serial/imx.c | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

-- 
2.34.1


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source
  2025-09-23  3:16 [PATCH 0/2] tty: serial: imx: improve the imx uart wakeup function Sherry Sun
@ 2025-09-23  3:16 ` Sherry Sun
  2025-09-23  8:32   ` Peng Fan
  2025-09-23 16:42   ` kernel test robot
  2025-09-23  3:16 ` [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting Sherry Sun
  1 sibling, 2 replies; 8+ messages in thread
From: Sherry Sun @ 2025-09-23  3:16 UTC (permalink / raw)
  To: gregkh, jirislaby, shawnguo, s.hauer, kernel, festevam,
	shenwei.wang
  Cc: linux-serial, linux-kernel, imx

Currently, imx uart defaults to enabling the wake related registers for
all uart devices. However, it is unnecessary for those devices not
configured as wakeup source, so add device_may_wakeup() check before
configuring the uart wake related registers.

Fixes: db1a9b55004c ("tty: serial: imx: Allow UART to be a source for wakeup")
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
---
 drivers/tty/serial/imx.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 500dfc009d03..4ddfc89816bf 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -2697,7 +2697,22 @@ static void imx_uart_save_context(struct imx_port *sport)
 /* called with irq off */
 static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)
 {
+	struct tty_port *port = &sport->port.state->port;
+	struct tty_struct *tty;
+	struct device *tty_dev;
 	u32 ucr3;
+	bool may_wake;
+
+	tty = tty_port_tty_get(port);
+	if (tty) {
+		tty_dev = tty->dev;
+		may_wake = tty_dev && device_may_wakeup(tty_dev);
+		tty_kref_put(tty);
+	}
+
+	/* only configure the wake register when device set as wakeup source */
+	if (!may_wake)
+		return;
 
 	uart_port_lock_irq(&sport->port);
 
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting
  2025-09-23  3:16 [PATCH 0/2] tty: serial: imx: improve the imx uart wakeup function Sherry Sun
  2025-09-23  3:16 ` [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source Sherry Sun
@ 2025-09-23  3:16 ` Sherry Sun
  2025-09-23 17:35   ` kernel test robot
  2025-09-23 18:27   ` kernel test robot
  1 sibling, 2 replies; 8+ messages in thread
From: Sherry Sun @ 2025-09-23  3:16 UTC (permalink / raw)
  To: gregkh, jirislaby, shawnguo, s.hauer, kernel, festevam,
	shenwei.wang
  Cc: linux-serial, linux-kernel, imx

Current imx uart wakeup event would not report itself through sysfs as
being the source of wakeup, add pm_wakeup_event() to support this.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
---
 drivers/tty/serial/imx.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 4ddfc89816bf..647123da04f5 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -2700,8 +2700,8 @@ static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)
 	struct tty_port *port = &sport->port.state->port;
 	struct tty_struct *tty;
 	struct device *tty_dev;
-	u32 ucr3;
-	bool may_wake;
+	u32 ucr3, usr1;
+	bool may_wake, wake_active;
 
 	tty = tty_port_tty_get(port);
 	if (tty) {
@@ -2716,12 +2716,14 @@ static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)
 
 	uart_port_lock_irq(&sport->port);
 
+	usr1 = imx_uart_readl(sport, USR1);
 	ucr3 = imx_uart_readl(sport, UCR3);
 	if (on) {
 		imx_uart_writel(sport, USR1_AWAKE, USR1);
 		ucr3 |= UCR3_AWAKEN;
 	} else {
 		ucr3 &= ~UCR3_AWAKEN;
+		wake_active = usr1 & USR1_AWAKE;
 	}
 	imx_uart_writel(sport, ucr3, UCR3);
 
@@ -2732,10 +2734,14 @@ static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)
 			ucr1 |= UCR1_RTSDEN;
 		} else {
 			ucr1 &= ~UCR1_RTSDEN;
+			wake_active |= usr1 & USR1_RTSD;
 		}
 		imx_uart_writel(sport, ucr1, UCR1);
 	}
 
+	if (wake_active && irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq)))
+		pm_wakeup_event(tty_port_tty_get(port)->dev, 0);
+
 	uart_port_unlock_irq(&sport->port);
 }
 
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* RE: [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source
  2025-09-23  8:32   ` Peng Fan
@ 2025-09-23  7:36     ` Sherry Sun
  0 siblings, 0 replies; 8+ messages in thread
From: Sherry Sun @ 2025-09-23  7:36 UTC (permalink / raw)
  To: Peng Fan (OSS)
  Cc: gregkh@linuxfoundation.org, jirislaby@kernel.org,
	shawnguo@kernel.org, s.hauer@pengutronix.de,
	kernel@pengutronix.de, festevam@gmail.com, Shenwei Wang,
	linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
	imx@lists.linux.dev



> -----Original Message-----
> From: Peng Fan (OSS) <peng.fan@oss.nxp.com>
> Sent: Tuesday, September 23, 2025 4:32 PM
> To: Sherry Sun <sherry.sun@nxp.com>
> Cc: gregkh@linuxfoundation.org; jirislaby@kernel.org; shawnguo@kernel.org;
> s.hauer@pengutronix.de; kernel@pengutronix.de; festevam@gmail.com;
> Shenwei Wang <shenwei.wang@nxp.com>; linux-serial@vger.kernel.org;
> linux-kernel@vger.kernel.org; imx@lists.linux.dev
> Subject: Re: [PATCH 1/2] tty: serial: imx: Only configure the wake register when
> device is set as wakeup source
> 
> On Tue, Sep 23, 2025 at 11:16:12AM +0800, Sherry Sun wrote:
> >Currently, imx uart defaults to enabling the wake related registers for
> >all uart devices. However, it is unnecessary for those devices not
> >configured as wakeup source, so add device_may_wakeup() check before
> >configuring the uart wake related registers.
> 
> I would rewrite as this:
> Currently, the i.MX UART driver enables wake-related registers for all UART
> devices by default. However, this is unnecessary for devices that are not
> configured as wakeup sources. To address this, add a device_may_wakeup()
> check before configuring the UART wake-related registers.

Thanks, that's much clearer.

> 
> >
> >Fixes: db1a9b55004c ("tty: serial: imx: Allow UART to be a source for
> >wakeup")
> >Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
> >---
> > drivers/tty/serial/imx.c | 15 +++++++++++++++
> > 1 file changed, 15 insertions(+)
> >
> >diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index
> >500dfc009d03..4ddfc89816bf 100644
> >--- a/drivers/tty/serial/imx.c
> >+++ b/drivers/tty/serial/imx.c
> >@@ -2697,7 +2697,22 @@ static void imx_uart_save_context(struct
> >imx_port *sport)
> > /* called with irq off */
> > static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)  {
> >+	struct tty_port *port = &sport->port.state->port;
> >+	struct tty_struct *tty;
> >+	struct device *tty_dev;
> > 	u32 ucr3;
> >+	bool may_wake;
> 
> 'bool may_wake = false;' otherwise there might be report on using an
> uninitalized value by coverity or other tools.

Ok, will fix this in V2.

Best Regards
Sherry

> 
> >+
> >+	tty = tty_port_tty_get(port);
> >+	if (tty) {
> >+		tty_dev = tty->dev;
> >+		may_wake = tty_dev && device_may_wakeup(tty_dev);
> >+		tty_kref_put(tty);
> >+	}
> >+
> >+	/* only configure the wake register when device set as wakeup source
> */
> >+	if (!may_wake)
> >+		return;
> 
> Regards,
> Peng

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source
  2025-09-23  3:16 ` [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source Sherry Sun
@ 2025-09-23  8:32   ` Peng Fan
  2025-09-23  7:36     ` Sherry Sun
  2025-09-23 16:42   ` kernel test robot
  1 sibling, 1 reply; 8+ messages in thread
From: Peng Fan @ 2025-09-23  8:32 UTC (permalink / raw)
  To: Sherry Sun
  Cc: gregkh, jirislaby, shawnguo, s.hauer, kernel, festevam,
	shenwei.wang, linux-serial, linux-kernel, imx

On Tue, Sep 23, 2025 at 11:16:12AM +0800, Sherry Sun wrote:
>Currently, imx uart defaults to enabling the wake related registers for
>all uart devices. However, it is unnecessary for those devices not
>configured as wakeup source, so add device_may_wakeup() check before
>configuring the uart wake related registers.

I would rewrite as this:
Currently, the i.MX UART driver enables wake-related registers for all UART
devices by default. However, this is unnecessary for devices that are not
configured as wakeup sources. To address this, add a device_may_wakeup()
check before configuring the UART wake-related registers.

>
>Fixes: db1a9b55004c ("tty: serial: imx: Allow UART to be a source for wakeup")
>Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
>---
> drivers/tty/serial/imx.c | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
>diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
>index 500dfc009d03..4ddfc89816bf 100644
>--- a/drivers/tty/serial/imx.c
>+++ b/drivers/tty/serial/imx.c
>@@ -2697,7 +2697,22 @@ static void imx_uart_save_context(struct imx_port *sport)
> /* called with irq off */
> static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)
> {
>+	struct tty_port *port = &sport->port.state->port;
>+	struct tty_struct *tty;
>+	struct device *tty_dev;
> 	u32 ucr3;
>+	bool may_wake;

'bool may_wake = false;' otherwise there might be report on using an
uninitalized value by coverity or other tools.

>+
>+	tty = tty_port_tty_get(port);
>+	if (tty) {
>+		tty_dev = tty->dev;
>+		may_wake = tty_dev && device_may_wakeup(tty_dev);
>+		tty_kref_put(tty);
>+	}
>+
>+	/* only configure the wake register when device set as wakeup source */
>+	if (!may_wake)
>+		return;

Regards,
Peng

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source
  2025-09-23  3:16 ` [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source Sherry Sun
  2025-09-23  8:32   ` Peng Fan
@ 2025-09-23 16:42   ` kernel test robot
  1 sibling, 0 replies; 8+ messages in thread
From: kernel test robot @ 2025-09-23 16:42 UTC (permalink / raw)
  To: Sherry Sun, gregkh, jirislaby, shawnguo, s.hauer, kernel,
	festevam, shenwei.wang
  Cc: llvm, oe-kbuild-all, linux-serial, linux-kernel, imx

Hi Sherry,

kernel test robot noticed the following build warnings:

[auto build test WARNING on shawnguo/for-next]
[also build test WARNING on tty/tty-testing tty/tty-next tty/tty-linus usb/usb-testing usb/usb-next usb/usb-linus linus/master v6.17-rc7 next-20250922]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Sherry-Sun/tty-serial-imx-Only-configure-the-wake-register-when-device-is-set-as-wakeup-source/20250923-111951
base:   https://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux.git for-next
patch link:    https://lore.kernel.org/r/20250923031613.2448073-2-sherry.sun%40nxp.com
patch subject: [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source
config: arm-randconfig-004-20250923 (https://download.01.org/0day-ci/archive/20250924/202509240009.Q4htWwxE-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project cafc064fc7a96b3979a023ddae1da2b499d6c954)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250924/202509240009.Q4htWwxE-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509240009.Q4htWwxE-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/tty/serial/imx.c:2707:6: warning: variable 'may_wake' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
    2707 |         if (tty) {
         |             ^~~
   drivers/tty/serial/imx.c:2714:7: note: uninitialized use occurs here
    2714 |         if (!may_wake)
         |              ^~~~~~~~
   drivers/tty/serial/imx.c:2707:2: note: remove the 'if' if its condition is always true
    2707 |         if (tty) {
         |         ^~~~~~~~
   drivers/tty/serial/imx.c:2704:15: note: initialize the variable 'may_wake' to silence this warning
    2704 |         bool may_wake;
         |                      ^
         |                       = 0
   1 warning generated.


vim +2707 drivers/tty/serial/imx.c

  2696	
  2697	/* called with irq off */
  2698	static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)
  2699	{
  2700		struct tty_port *port = &sport->port.state->port;
  2701		struct tty_struct *tty;
  2702		struct device *tty_dev;
  2703		u32 ucr3;
  2704		bool may_wake;
  2705	
  2706		tty = tty_port_tty_get(port);
> 2707		if (tty) {
  2708			tty_dev = tty->dev;
  2709			may_wake = tty_dev && device_may_wakeup(tty_dev);
  2710			tty_kref_put(tty);
  2711		}
  2712	
  2713		/* only configure the wake register when device set as wakeup source */
  2714		if (!may_wake)
  2715			return;
  2716	
  2717		uart_port_lock_irq(&sport->port);
  2718	
  2719		ucr3 = imx_uart_readl(sport, UCR3);
  2720		if (on) {
  2721			imx_uart_writel(sport, USR1_AWAKE, USR1);
  2722			ucr3 |= UCR3_AWAKEN;
  2723		} else {
  2724			ucr3 &= ~UCR3_AWAKEN;
  2725		}
  2726		imx_uart_writel(sport, ucr3, UCR3);
  2727	
  2728		if (sport->have_rtscts) {
  2729			u32 ucr1 = imx_uart_readl(sport, UCR1);
  2730			if (on) {
  2731				imx_uart_writel(sport, USR1_RTSD, USR1);
  2732				ucr1 |= UCR1_RTSDEN;
  2733			} else {
  2734				ucr1 &= ~UCR1_RTSDEN;
  2735			}
  2736			imx_uart_writel(sport, ucr1, UCR1);
  2737		}
  2738	
  2739		uart_port_unlock_irq(&sport->port);
  2740	}
  2741	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting
  2025-09-23  3:16 ` [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting Sherry Sun
@ 2025-09-23 17:35   ` kernel test robot
  2025-09-23 18:27   ` kernel test robot
  1 sibling, 0 replies; 8+ messages in thread
From: kernel test robot @ 2025-09-23 17:35 UTC (permalink / raw)
  To: Sherry Sun, gregkh, jirislaby, shawnguo, s.hauer, kernel,
	festevam, shenwei.wang
  Cc: llvm, oe-kbuild-all, linux-serial, linux-kernel, imx

Hi Sherry,

kernel test robot noticed the following build errors:

[auto build test ERROR on shawnguo/for-next]
[also build test ERROR on usb/usb-testing usb/usb-next usb/usb-linus linus/master v6.17-rc7 next-20250922]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Sherry-Sun/tty-serial-imx-Only-configure-the-wake-register-when-device-is-set-as-wakeup-source/20250923-111951
base:   https://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux.git for-next
patch link:    https://lore.kernel.org/r/20250923031613.2448073-3-sherry.sun%40nxp.com
patch subject: [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting
config: x86_64-buildonly-randconfig-004-20250923 (https://download.01.org/0day-ci/archive/20250924/202509240146.aj950Liu-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250924/202509240146.aj950Liu-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509240146.aj950Liu-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/tty/serial/imx.c:2742:21: error: call to undeclared function 'irqd_is_wakeup_set'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
    2742 |         if (wake_active && irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq)))
         |                            ^
>> drivers/tty/serial/imx.c:2742:40: error: call to undeclared function 'irq_get_irq_data'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
    2742 |         if (wake_active && irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq)))
         |                                               ^
   drivers/tty/serial/imx.c:2742:40: note: did you mean 'irq_set_irq_wake'?
   include/linux/interrupt.h:481:12: note: 'irq_set_irq_wake' declared here
     481 | extern int irq_set_irq_wake(unsigned int irq, unsigned int on);
         |            ^
   2 errors generated.


vim +/irqd_is_wakeup_set +2742 drivers/tty/serial/imx.c

  2696	
  2697	/* called with irq off */
  2698	static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)
  2699	{
  2700		struct tty_port *port = &sport->port.state->port;
  2701		struct tty_struct *tty;
  2702		struct device *tty_dev;
  2703		u32 ucr3, usr1;
  2704		bool may_wake, wake_active;
  2705	
  2706		tty = tty_port_tty_get(port);
  2707		if (tty) {
  2708			tty_dev = tty->dev;
  2709			may_wake = tty_dev && device_may_wakeup(tty_dev);
  2710			tty_kref_put(tty);
  2711		}
  2712	
  2713		/* only configure the wake register when device set as wakeup source */
  2714		if (!may_wake)
  2715			return;
  2716	
  2717		uart_port_lock_irq(&sport->port);
  2718	
  2719		usr1 = imx_uart_readl(sport, USR1);
  2720		ucr3 = imx_uart_readl(sport, UCR3);
  2721		if (on) {
  2722			imx_uart_writel(sport, USR1_AWAKE, USR1);
  2723			ucr3 |= UCR3_AWAKEN;
  2724		} else {
  2725			ucr3 &= ~UCR3_AWAKEN;
  2726			wake_active = usr1 & USR1_AWAKE;
  2727		}
  2728		imx_uart_writel(sport, ucr3, UCR3);
  2729	
  2730		if (sport->have_rtscts) {
  2731			u32 ucr1 = imx_uart_readl(sport, UCR1);
  2732			if (on) {
  2733				imx_uart_writel(sport, USR1_RTSD, USR1);
  2734				ucr1 |= UCR1_RTSDEN;
  2735			} else {
  2736				ucr1 &= ~UCR1_RTSDEN;
  2737				wake_active |= usr1 & USR1_RTSD;
  2738			}
  2739			imx_uart_writel(sport, ucr1, UCR1);
  2740		}
  2741	
> 2742		if (wake_active && irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq)))
  2743			pm_wakeup_event(tty_port_tty_get(port)->dev, 0);
  2744	
  2745		uart_port_unlock_irq(&sport->port);
  2746	}
  2747	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting
  2025-09-23  3:16 ` [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting Sherry Sun
  2025-09-23 17:35   ` kernel test robot
@ 2025-09-23 18:27   ` kernel test robot
  1 sibling, 0 replies; 8+ messages in thread
From: kernel test robot @ 2025-09-23 18:27 UTC (permalink / raw)
  To: Sherry Sun, gregkh, jirislaby, shawnguo, s.hauer, kernel,
	festevam, shenwei.wang
  Cc: llvm, oe-kbuild-all, linux-serial, linux-kernel, imx

Hi Sherry,

kernel test robot noticed the following build warnings:

[auto build test WARNING on shawnguo/for-next]
[also build test WARNING on tty/tty-testing tty/tty-next tty/tty-linus usb/usb-testing usb/usb-next usb/usb-linus linus/master v6.17-rc7 next-20250922]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Sherry-Sun/tty-serial-imx-Only-configure-the-wake-register-when-device-is-set-as-wakeup-source/20250923-111951
base:   https://git.kernel.org/pub/scm/linux/kernel/git/shawnguo/linux.git for-next
patch link:    https://lore.kernel.org/r/20250923031613.2448073-3-sherry.sun%40nxp.com
patch subject: [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting
config: arm-randconfig-004-20250923 (https://download.01.org/0day-ci/archive/20250924/202509240214.bHWiT4Db-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project cafc064fc7a96b3979a023ddae1da2b499d6c954)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250924/202509240214.bHWiT4Db-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509240214.bHWiT4Db-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/tty/serial/imx.c:2721:6: warning: variable 'wake_active' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
    2721 |         if (on) {
         |             ^~
   drivers/tty/serial/imx.c:2742:6: note: uninitialized use occurs here
    2742 |         if (wake_active && irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq)))
         |             ^~~~~~~~~~~
   drivers/tty/serial/imx.c:2721:2: note: remove the 'if' if its condition is always false
    2721 |         if (on) {
         |         ^~~~~~~~~
    2722 |                 imx_uart_writel(sport, USR1_AWAKE, USR1);
         |                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    2723 |                 ucr3 |= UCR3_AWAKEN;
         |                 ~~~~~~~~~~~~~~~~~~~~
    2724 |         } else {
         |         ~~~~~~
   drivers/tty/serial/imx.c:2704:28: note: initialize the variable 'wake_active' to silence this warning
    2704 |         bool may_wake, wake_active;
         |                                   ^
         |                                    = 0
   drivers/tty/serial/imx.c:2707:6: warning: variable 'may_wake' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
    2707 |         if (tty) {
         |             ^~~
   drivers/tty/serial/imx.c:2714:7: note: uninitialized use occurs here
    2714 |         if (!may_wake)
         |              ^~~~~~~~
   drivers/tty/serial/imx.c:2707:2: note: remove the 'if' if its condition is always true
    2707 |         if (tty) {
         |         ^~~~~~~~
   drivers/tty/serial/imx.c:2704:15: note: initialize the variable 'may_wake' to silence this warning
    2704 |         bool may_wake, wake_active;
         |                      ^
         |                       = 0
   2 warnings generated.


vim +2721 drivers/tty/serial/imx.c

c868cbb7e5c6d3 Eduardo Valentin 2015-08-11  2696  
3c199ed5bd6469 Esben Haabendal  2024-09-13  2697  /* called with irq off */
9d1a50a2cceb3a Uwe Kleine-König 2018-03-02  2698  static void imx_uart_enable_wakeup(struct imx_port *sport, bool on)
189550b8644ef5 Eduardo Valentin 2015-08-11  2699  {
519ca97b8a2e94 Sherry Sun       2025-09-23  2700  	struct tty_port *port = &sport->port.state->port;
519ca97b8a2e94 Sherry Sun       2025-09-23  2701  	struct tty_struct *tty;
519ca97b8a2e94 Sherry Sun       2025-09-23  2702  	struct device *tty_dev;
2e33c984e6b3d6 Sherry Sun       2025-09-23  2703  	u32 ucr3, usr1;
2e33c984e6b3d6 Sherry Sun       2025-09-23  2704  	bool may_wake, wake_active;
519ca97b8a2e94 Sherry Sun       2025-09-23  2705  
519ca97b8a2e94 Sherry Sun       2025-09-23  2706  	tty = tty_port_tty_get(port);
519ca97b8a2e94 Sherry Sun       2025-09-23  2707  	if (tty) {
519ca97b8a2e94 Sherry Sun       2025-09-23  2708  		tty_dev = tty->dev;
519ca97b8a2e94 Sherry Sun       2025-09-23  2709  		may_wake = tty_dev && device_may_wakeup(tty_dev);
519ca97b8a2e94 Sherry Sun       2025-09-23  2710  		tty_kref_put(tty);
519ca97b8a2e94 Sherry Sun       2025-09-23  2711  	}
519ca97b8a2e94 Sherry Sun       2025-09-23  2712  
519ca97b8a2e94 Sherry Sun       2025-09-23  2713  	/* only configure the wake register when device set as wakeup source */
519ca97b8a2e94 Sherry Sun       2025-09-23  2714  	if (!may_wake)
519ca97b8a2e94 Sherry Sun       2025-09-23  2715  		return;
189550b8644ef5 Eduardo Valentin 2015-08-11  2716  
fbd22c4fa737f9 Xiaolei Wang     2024-12-11  2717  	uart_port_lock_irq(&sport->port);
3c199ed5bd6469 Esben Haabendal  2024-09-13  2718  
2e33c984e6b3d6 Sherry Sun       2025-09-23  2719  	usr1 = imx_uart_readl(sport, USR1);
4444dcf1fe7ea5 Uwe Kleine-König 2018-03-02  2720  	ucr3 = imx_uart_readl(sport, UCR3);
09df0b3464e528 Martin Kaiser    2018-01-05 @2721  	if (on) {
27c844261b87f8 Uwe Kleine-König 2018-03-02  2722  		imx_uart_writel(sport, USR1_AWAKE, USR1);
4444dcf1fe7ea5 Uwe Kleine-König 2018-03-02  2723  		ucr3 |= UCR3_AWAKEN;
4444dcf1fe7ea5 Uwe Kleine-König 2018-03-02  2724  	} else {
4444dcf1fe7ea5 Uwe Kleine-König 2018-03-02  2725  		ucr3 &= ~UCR3_AWAKEN;
2e33c984e6b3d6 Sherry Sun       2025-09-23  2726  		wake_active = usr1 & USR1_AWAKE;
09df0b3464e528 Martin Kaiser    2018-01-05  2727  	}
4444dcf1fe7ea5 Uwe Kleine-König 2018-03-02  2728  	imx_uart_writel(sport, ucr3, UCR3);
bc85734b126f81 Eduardo Valentin 2015-08-11  2729  
38b1f0fb42f772 Fabio Estevam    2018-01-04  2730  	if (sport->have_rtscts) {
4444dcf1fe7ea5 Uwe Kleine-König 2018-03-02  2731  		u32 ucr1 = imx_uart_readl(sport, UCR1);
c67643b46c28fc Fugang Duan      2021-11-25  2732  		if (on) {
c67643b46c28fc Fugang Duan      2021-11-25  2733  			imx_uart_writel(sport, USR1_RTSD, USR1);
4444dcf1fe7ea5 Uwe Kleine-König 2018-03-02  2734  			ucr1 |= UCR1_RTSDEN;
c67643b46c28fc Fugang Duan      2021-11-25  2735  		} else {
4444dcf1fe7ea5 Uwe Kleine-König 2018-03-02  2736  			ucr1 &= ~UCR1_RTSDEN;
2e33c984e6b3d6 Sherry Sun       2025-09-23  2737  			wake_active |= usr1 & USR1_RTSD;
c67643b46c28fc Fugang Duan      2021-11-25  2738  		}
4444dcf1fe7ea5 Uwe Kleine-König 2018-03-02  2739  		imx_uart_writel(sport, ucr1, UCR1);
189550b8644ef5 Eduardo Valentin 2015-08-11  2740  	}
3c199ed5bd6469 Esben Haabendal  2024-09-13  2741  
2e33c984e6b3d6 Sherry Sun       2025-09-23  2742  	if (wake_active && irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq)))
2e33c984e6b3d6 Sherry Sun       2025-09-23  2743  		pm_wakeup_event(tty_port_tty_get(port)->dev, 0);
2e33c984e6b3d6 Sherry Sun       2025-09-23  2744  
fbd22c4fa737f9 Xiaolei Wang     2024-12-11  2745  	uart_port_unlock_irq(&sport->port);
38b1f0fb42f772 Fabio Estevam    2018-01-04  2746  }
189550b8644ef5 Eduardo Valentin 2015-08-11  2747  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

^ permalink raw reply	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2025-09-23 18:27 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-09-23  3:16 [PATCH 0/2] tty: serial: imx: improve the imx uart wakeup function Sherry Sun
2025-09-23  3:16 ` [PATCH 1/2] tty: serial: imx: Only configure the wake register when device is set as wakeup source Sherry Sun
2025-09-23  8:32   ` Peng Fan
2025-09-23  7:36     ` Sherry Sun
2025-09-23 16:42   ` kernel test robot
2025-09-23  3:16 ` [PATCH 2/2] tty: serial: imx: Add missing wakeup event reporting Sherry Sun
2025-09-23 17:35   ` kernel test robot
2025-09-23 18:27   ` kernel test robot

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