diff mbox

[PATCH/Resend,2/2] arm: mach-omap2: prevent UART console idle on suspend while using "no_console_suspend"

Message ID 515E7876.3080407@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

Poddar, Sourav April 5, 2013, 7:08 a.m. UTC
Hi Kevin,
On Wednesday 03 April 2013 11:18 PM, Kevin Hilman wrote:
> Sourav Poddar<sourav.poddar@ti.com>  writes:
>
>> Hi Kevin,
>> On Wednesday 20 March 2013 05:36 PM, Sourav Poddar wrote:
>>> Realised the list  to whom the patch was send got dropped. Ccing
>>> them all..
>>> On Wednesday 20 March 2013 05:18 PM, Sourav Poddar wrote:
>>>> Hi Kevin,
>>>> On Tuesday 19 March 2013 12:24 AM, Kevin Hilman wrote:
>>>>> Sourav Poddar<sourav.poddar@ti.com>   writes:
>>>>>
>>>>>> With dt boot, uart wakeup after suspend is non functional on
>>>>>> omap4/5 while using
>>>>>> "no_console_suspend" in the bootargs. With "no_console_suspend"
>>>>>> used, od->flags
>>>>>> should be ORed with "OMAP_DEVICE_NO_IDLE_ON_SUSPEND", thereby not
>>>>>> allowing the console
>>>>>> to idle in the suspend path. For non-dt case, this was taken care
>>>>>> by platform data.
>>>>>>
>>>>>> Tested on omap5430evm, omap4430sdp.
>>>>>>
>>>>>> Cc: Santosh Shilimkar<santosh.shilimkar@ti.com>
>>>>>> Cc: Felipe Balbi<balbi@ti.com>
>>>>>> Cc: Rajendra nayak<rnayak@ti.com>
>>>>>> Signed-off-by: Sourav Poddar<sourav.poddar@ti.com>
>>>>> This patch creates a dependency between omap_device (generic,
>>>>> device-independent code) and a specific driver (UART.)
>>>>>
>>>>> If you need to do something like this that's DT boot specific, then
>>>>> we probably need some late initcall in serial.c to handle this.
>>>>> It does
>>>>> not belong in omap_device.
>>>>>
>>>> The following function "omap_device_disable_idle_on_suspend(pdev)"
>>>> should only
>>>> be called once the omap device has been build, which in the case of
>>>> device tree is
>>>> done in omap_device.c file. Moreover, the above call should be
>>>> executed conditionally
>>>> and should depend on the following two parameter.
>>>>
>>>> [1]  a. Whether "no_console_suspend" is set and
>>>>       b.  the device build is a console uart.
>>>>
>>>> When I look closely into the serial.c file, I realised that
>>>> "core_initcall(omap_serial_early_init)" gets called irrespective
>>>> of dt/non dt boot and will take care of most of the stuff(checking
>>>> whether
>>>> "no_console_suspend" is used and which uart is used as a console
>>>> uart) which the
>>>> $subject patch is proposing.
>>>>
>>>> But the problem is that we need to exchange the parsed information
>>>> from serial.c to the omap_device file for the condtional execution of
>>>> "omap_device_disable_idle_on_suspend"
>>>>
>>>> In this case,
>>>> from "serial.c" we need
>>>>      1. no_console_suspend = true
>>>>      2. strcpy(console_name, oh_name), where oh_name corresponds to
>>>> the console uart.
>>>>
>>>> then in "omap_device.c" do
>>>>      if (no_console_suspend&&  !strcmp(oh->name, console_name))
>>>>                  omap_device_disable_idle_on_suspend(pdev);
>>>>
>>>> Please correct if I am understanding it incorrectly.
>>>>
>>>> If the above understanding looks good to you, is there a way we can
>>>> make this
>>>> exchange of information happen between serial.c and omap_device.c file?
>> Any input on this?
>> As I explained earlier, that there is a need to parse information in
>> serial.c and use that in
>> omap_device.c only after the device is build.
> As I explained earlier, any device specific hacks inside omap_device
> should be a red flag that something has gone wrong.
>
> How about fixing the UART driver/core to not runtime suspend if
> no_console_suspend is given?
>
> Then we can get rid of this no_idle_on_suspend hack all together since
> UART is the only remaining user.
>

Yes, that can be done.

I cooked up an experimental patch, based on your above suggestion. The 
patch is
inlined along with  the mail. I tested the patch and it resolves
the issue.

Depending on whether no_console_suspend is used or not, we can set a 
variable
which can be used as a condition in runtime api's in serial driver.

The information whether "no_console_suspend" is used or not is parsed in
serial.c file, and this need to be communicated to the driver layer.

In my experimental patch below, I have used an extern variable
"force_console_suspend_disable".

Do you see a better way of handling this without using extern?

---------
From: Sourav Poddar <sourav.poddar@ti.com>
Date: Wed, 13 Mar 2013 20:32:36 +0530
Subject: [PATCH] arm: mach-omap2: prevent UART console idle on suspend 
while using "no_console_suspend"

With dt boot, uart wakeup after suspend is non functional while using
"no_console_suspend" in the bootargs. With "no_console_suspend" used, 
od->flags
should be ORed with "OMAP_DEVICE_NO_IDLE_ON_SUSPEND", thereby not 
allowing the console
to idle in the suspend path.

Tested on omap5430evm, omap4430sdp.

Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
---
  arch/arm/mach-omap2/serial.c     |    6 ++++--
  drivers/tty/serial/omap-serial.c |    6 +++++-
  2 files changed, 9 insertions(+), 3 deletions(-)

      if (!pdata)
@@ -1614,6 +1615,9 @@ static int serial_omap_runtime_resume(struct 
device *dev)

      int loss_cnt = serial_omap_get_context_loss_count(up);

+    if (force_console_suspend_disable)
+        return -EINVAL;
+
      if (loss_cnt < 0) {
          dev_err(dev, "serial_omap_get_context_loss_count failed : %d\n",
              loss_cnt);

Comments

Santosh Shilimkar April 5, 2013, 7:15 a.m. UTC | #1
On Friday 05 April 2013 12:38 PM, Sourav Poddar wrote:
> Hi Kevin,
> On Wednesday 03 April 2013 11:18 PM, Kevin Hilman wrote:
>> Sourav Poddar<sourav.poddar@ti.com>  writes:
>>
>>> Hi Kevin,
>>> On Wednesday 20 March 2013 05:36 PM, Sourav Poddar wrote:
>>>> Realised the list  to whom the patch was send got dropped. Ccing
>>>> them all..
>>>> On Wednesday 20 March 2013 05:18 PM, Sourav Poddar wrote:
>>>>> Hi Kevin,
>>>>> On Tuesday 19 March 2013 12:24 AM, Kevin Hilman wrote:
>>>>>> Sourav Poddar<sourav.poddar@ti.com>   writes:
>>>>>>
>>>>>>> With dt boot, uart wakeup after suspend is non functional on
>>>>>>> omap4/5 while using
>>>>>>> "no_console_suspend" in the bootargs. With "no_console_suspend"
>>>>>>> used, od->flags
>>>>>>> should be ORed with "OMAP_DEVICE_NO_IDLE_ON_SUSPEND", thereby not
>>>>>>> allowing the console
>>>>>>> to idle in the suspend path. For non-dt case, this was taken care
>>>>>>> by platform data.
>>>>>>>
>>>>>>> Tested on omap5430evm, omap4430sdp.
>>>>>>>
>>>>>>> Cc: Santosh Shilimkar<santosh.shilimkar@ti.com>
>>>>>>> Cc: Felipe Balbi<balbi@ti.com>
>>>>>>> Cc: Rajendra nayak<rnayak@ti.com>
>>>>>>> Signed-off-by: Sourav Poddar<sourav.poddar@ti.com>
>>>>>> This patch creates a dependency between omap_device (generic,
>>>>>> device-independent code) and a specific driver (UART.)
>>>>>>
>>>>>> If you need to do something like this that's DT boot specific, then
>>>>>> we probably need some late initcall in serial.c to handle this.
>>>>>> It does
>>>>>> not belong in omap_device.
>>>>>>
>>>>> The following function "omap_device_disable_idle_on_suspend(pdev)"
>>>>> should only
>>>>> be called once the omap device has been build, which in the case of
>>>>> device tree is
>>>>> done in omap_device.c file. Moreover, the above call should be
>>>>> executed conditionally
>>>>> and should depend on the following two parameter.
>>>>>
>>>>> [1]  a. Whether "no_console_suspend" is set and
>>>>>       b.  the device build is a console uart.
>>>>>
>>>>> When I look closely into the serial.c file, I realised that
>>>>> "core_initcall(omap_serial_early_init)" gets called irrespective
>>>>> of dt/non dt boot and will take care of most of the stuff(checking
>>>>> whether
>>>>> "no_console_suspend" is used and which uart is used as a console
>>>>> uart) which the
>>>>> $subject patch is proposing.
>>>>>
>>>>> But the problem is that we need to exchange the parsed information
>>>>> from serial.c to the omap_device file for the condtional execution of
>>>>> "omap_device_disable_idle_on_suspend"
>>>>>
>>>>> In this case,
>>>>> from "serial.c" we need
>>>>>      1. no_console_suspend = true
>>>>>      2. strcpy(console_name, oh_name), where oh_name corresponds to
>>>>> the console uart.
>>>>>
>>>>> then in "omap_device.c" do
>>>>>      if (no_console_suspend&&  !strcmp(oh->name, console_name))
>>>>>                  omap_device_disable_idle_on_suspend(pdev);
>>>>>
>>>>> Please correct if I am understanding it incorrectly.
>>>>>
>>>>> If the above understanding looks good to you, is there a way we can
>>>>> make this
>>>>> exchange of information happen between serial.c and omap_device.c file?
>>> Any input on this?
>>> As I explained earlier, that there is a need to parse information in
>>> serial.c and use that in
>>> omap_device.c only after the device is build.
>> As I explained earlier, any device specific hacks inside omap_device
>> should be a red flag that something has gone wrong.
>>
>> How about fixing the UART driver/core to not runtime suspend if
>> no_console_suspend is given?
>>
>> Then we can get rid of this no_idle_on_suspend hack all together since
>> UART is the only remaining user.
>>
> 
> Yes, that can be done.
> 
> I cooked up an experimental patch, based on your above suggestion. The patch is
> inlined along with  the mail. I tested the patch and it resolves
> the issue.
> 
Would be good to start a new thread.

> Depending on whether no_console_suspend is used or not, we can set a variable
> which can be used as a condition in runtime api's in serial driver.
> 
> The information whether "no_console_suspend" is used or not is parsed in
> serial.c file, and this need to be communicated to the driver layer.
> 
WHY ?
Serial core already knows about 'no_console_suspend' and thats used
to manage console lock.

> In my experimental patch below, I have used an extern variable
> "force_console_suspend_disable".
> 
> Do you see a better way of handling this without using extern?
> 
> ---------
> From: Sourav Poddar <sourav.poddar@ti.com>
> Date: Wed, 13 Mar 2013 20:32:36 +0530
> Subject: [PATCH] arm: mach-omap2: prevent UART console idle on suspend while using "no_console_suspend"
> 
> With dt boot, uart wakeup after suspend is non functional while using
> "no_console_suspend" in the bootargs. With "no_console_suspend" used, od->flags
> should be ORed with "OMAP_DEVICE_NO_IDLE_ON_SUSPEND", thereby not allowing the console
> to idle in the suspend path.
> 
> Tested on omap5430evm, omap4430sdp.
> 
> Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
> ---
>  arch/arm/mach-omap2/serial.c     |    6 ++++--
>  drivers/tty/serial/omap-serial.c |    6 +++++-
>  2 files changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
> index f660156..427c407 100644
> --- a/arch/arm/mach-omap2/serial.c
> +++ b/arch/arm/mach-omap2/serial.c
> @@ -51,7 +51,7 @@
>  #define DEFAULT_AUTOSUSPEND_DELAY    -1
> 
>  #define MAX_UART_HWMOD_NAME_LEN        16
> -
> +int force_console_suspend_disable;
>  struct omap_uart_state {
>      int num;
> 
> @@ -207,8 +207,10 @@ static int __init omap_serial_early_init(void)
>                      uart_name, uart->num);
>              }
> 
> -            if (cmdline_find_option("no_console_suspend"))
> +            if (cmdline_find_option("no_console_suspend")) {
> +                force_console_suspend_disable = 1;
>                  no_console_suspend = true;
> +            }
> 
>              /*
>               * omap-uart can be used for earlyprintk logs
> diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
> index 08332f3..395ade8 100644
> --- a/drivers/tty/serial/omap-serial.c
> +++ b/drivers/tty/serial/omap-serial.c
> @@ -43,6 +43,7 @@
>  #include <linux/pinctrl/consumer.h>
>  #include <linux/platform_data/serial-omap.h>
> 
> +extern int force_console_suspend_disable;
This is no good. You need to use the information from
core serial layer

>  #define OMAP_MAX_HSUART_PORTS    6
> 
>  #define UART_BUILD_REVISION(x, y)    (((x) << 8) | (y))
> @@ -1582,7 +1583,7 @@ static int serial_omap_runtime_suspend(struct device *dev)
>      struct uart_omap_port *up = dev_get_drvdata(dev);
>      struct omap_uart_port_info *pdata = dev->platform_data;
> 
> -    if (!up)
> +    if (!up || force_console_suspend_disable)
>          return -EINVAL;
> 
>      if (!pdata)
> @@ -1614,6 +1615,9 @@ static int serial_omap_runtime_resume(struct device *dev)
> 
>      int loss_cnt = serial_omap_get_context_loss_count(up);
> 
> +    if (force_console_suspend_disable)
> +        return -EINVAL;
> +
>      if (loss_cnt < 0) {
>          dev_err(dev, "serial_omap_get_context_loss_count failed : %d\n",
>              loss_cnt);

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Poddar, Sourav April 5, 2013, 1:08 p.m. UTC | #2
Hi Santosh,
On Friday 05 April 2013 12:45 PM, Santosh Shilimkar wrote:
> On Friday 05 April 2013 12:38 PM, Sourav Poddar wrote:
>> Hi Kevin,
>> On Wednesday 03 April 2013 11:18 PM, Kevin Hilman wrote:
>>> Sourav Poddar<sourav.poddar@ti.com>   writes:
>>>
>>>> Hi Kevin,
>>>> On Wednesday 20 March 2013 05:36 PM, Sourav Poddar wrote:
>>>>> Realised the list  to whom the patch was send got dropped. Ccing
>>>>> them all..
>>>>> On Wednesday 20 March 2013 05:18 PM, Sourav Poddar wrote:
>>>>>> Hi Kevin,
>>>>>> On Tuesday 19 March 2013 12:24 AM, Kevin Hilman wrote:
>>>>>>> Sourav Poddar<sourav.poddar@ti.com>    writes:
>>>>>>>
>>>>>>>> With dt boot, uart wakeup after suspend is non functional on
>>>>>>>> omap4/5 while using
>>>>>>>> "no_console_suspend" in the bootargs. With "no_console_suspend"
>>>>>>>> used, od->flags
>>>>>>>> should be ORed with "OMAP_DEVICE_NO_IDLE_ON_SUSPEND", thereby not
>>>>>>>> allowing the console
>>>>>>>> to idle in the suspend path. For non-dt case, this was taken care
>>>>>>>> by platform data.
>>>>>>>>
>>>>>>>> Tested on omap5430evm, omap4430sdp.
>>>>>>>>
>>>>>>>> Cc: Santosh Shilimkar<santosh.shilimkar@ti.com>
>>>>>>>> Cc: Felipe Balbi<balbi@ti.com>
>>>>>>>> Cc: Rajendra nayak<rnayak@ti.com>
>>>>>>>> Signed-off-by: Sourav Poddar<sourav.poddar@ti.com>
>>>>>>> This patch creates a dependency between omap_device (generic,
>>>>>>> device-independent code) and a specific driver (UART.)
>>>>>>>
>>>>>>> If you need to do something like this that's DT boot specific, then
>>>>>>> we probably need some late initcall in serial.c to handle this.
>>>>>>> It does
>>>>>>> not belong in omap_device.
>>>>>>>
>>>>>> The following function "omap_device_disable_idle_on_suspend(pdev)"
>>>>>> should only
>>>>>> be called once the omap device has been build, which in the case of
>>>>>> device tree is
>>>>>> done in omap_device.c file. Moreover, the above call should be
>>>>>> executed conditionally
>>>>>> and should depend on the following two parameter.
>>>>>>
>>>>>> [1]  a. Whether "no_console_suspend" is set and
>>>>>>        b.  the device build is a console uart.
>>>>>>
>>>>>> When I look closely into the serial.c file, I realised that
>>>>>> "core_initcall(omap_serial_early_init)" gets called irrespective
>>>>>> of dt/non dt boot and will take care of most of the stuff(checking
>>>>>> whether
>>>>>> "no_console_suspend" is used and which uart is used as a console
>>>>>> uart) which the
>>>>>> $subject patch is proposing.
>>>>>>
>>>>>> But the problem is that we need to exchange the parsed information
>>>>>> from serial.c to the omap_device file for the condtional execution of
>>>>>> "omap_device_disable_idle_on_suspend"
>>>>>>
>>>>>> In this case,
>>>>>> from "serial.c" we need
>>>>>>       1. no_console_suspend = true
>>>>>>       2. strcpy(console_name, oh_name), where oh_name corresponds to
>>>>>> the console uart.
>>>>>>
>>>>>> then in "omap_device.c" do
>>>>>>       if (no_console_suspend&&   !strcmp(oh->name, console_name))
>>>>>>                   omap_device_disable_idle_on_suspend(pdev);
>>>>>>
>>>>>> Please correct if I am understanding it incorrectly.
>>>>>>
>>>>>> If the above understanding looks good to you, is there a way we can
>>>>>> make this
>>>>>> exchange of information happen between serial.c and omap_device.c file?
>>>> Any input on this?
>>>> As I explained earlier, that there is a need to parse information in
>>>> serial.c and use that in
>>>> omap_device.c only after the device is build.
>>> As I explained earlier, any device specific hacks inside omap_device
>>> should be a red flag that something has gone wrong.
>>>
>>> How about fixing the UART driver/core to not runtime suspend if
>>> no_console_suspend is given?
>>>
>>> Then we can get rid of this no_idle_on_suspend hack all together since
>>> UART is the only remaining user.
>>>
>> Yes, that can be done.
>>
>> I cooked up an experimental patch, based on your above suggestion. The patch is
>> inlined along with  the mail. I tested the patch and it resolves
>> the issue.
>>
> Would be good to start a new thread.
>
I will post a new version based on your comments below.
>> Depending on whether no_console_suspend is used or not, we can set a variable
>> which can be used as a condition in runtime api's in serial driver.
>>
>> The information whether "no_console_suspend" is used or not is parsed in
>> serial.c file, and this need to be communicated to the driver layer.
>>
> WHY ?
> Serial core already knows about 'no_console_suspend' and thats used
> to manage console lock.
>
True.
>> In my experimental patch below, I have used an extern variable
>> "force_console_suspend_disable".
>>
>> Do you see a better way of handling this without using extern?
>>
>> ---------
>> From: Sourav Poddar<sourav.poddar@ti.com>
>> Date: Wed, 13 Mar 2013 20:32:36 +0530
>> Subject: [PATCH] arm: mach-omap2: prevent UART console idle on suspend while using "no_console_suspend"
>>
>> With dt boot, uart wakeup after suspend is non functional while using
>> "no_console_suspend" in the bootargs. With "no_console_suspend" used, od->flags
>> should be ORed with "OMAP_DEVICE_NO_IDLE_ON_SUSPEND", thereby not allowing the console
>> to idle in the suspend path.
>>
>> Tested on omap5430evm, omap4430sdp.
>>
>> Signed-off-by: Sourav Poddar<sourav.poddar@ti.com>
>> ---
>>   arch/arm/mach-omap2/serial.c     |    6 ++++--
>>   drivers/tty/serial/omap-serial.c |    6 +++++-
>>   2 files changed, 9 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
>> index f660156..427c407 100644
>> --- a/arch/arm/mach-omap2/serial.c
>> +++ b/arch/arm/mach-omap2/serial.c
>> @@ -51,7 +51,7 @@
>>   #define DEFAULT_AUTOSUSPEND_DELAY    -1
>>
>>   #define MAX_UART_HWMOD_NAME_LEN        16
>> -
>> +int force_console_suspend_disable;
>>   struct omap_uart_state {
>>       int num;
>>
>> @@ -207,8 +207,10 @@ static int __init omap_serial_early_init(void)
>>                       uart_name, uart->num);
>>               }
>>
>> -            if (cmdline_find_option("no_console_suspend"))
>> +            if (cmdline_find_option("no_console_suspend")) {
>> +                force_console_suspend_disable = 1;
>>                   no_console_suspend = true;
>> +            }
>>
>>               /*
>>                * omap-uart can be used for earlyprintk logs
>> diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
>> index 08332f3..395ade8 100644
>> --- a/drivers/tty/serial/omap-serial.c
>> +++ b/drivers/tty/serial/omap-serial.c
>> @@ -43,6 +43,7 @@
>>   #include<linux/pinctrl/consumer.h>
>>   #include<linux/platform_data/serial-omap.h>
>>
>> +extern int force_console_suspend_disable;
> This is no good. You need to use the information from
> core serial layer
>
Ok. Will change.
>>   #define OMAP_MAX_HSUART_PORTS    6
>>
>>   #define UART_BUILD_REVISION(x, y)    (((x)<<  8) | (y))
>> @@ -1582,7 +1583,7 @@ static int serial_omap_runtime_suspend(struct device *dev)
>>       struct uart_omap_port *up = dev_get_drvdata(dev);
>>       struct omap_uart_port_info *pdata = dev->platform_data;
>>
>> -    if (!up)
>> +    if (!up || force_console_suspend_disable)
>>           return -EINVAL;
>>
>>       if (!pdata)
>> @@ -1614,6 +1615,9 @@ static int serial_omap_runtime_resume(struct device *dev)
>>
>>       int loss_cnt = serial_omap_get_context_loss_count(up);
>>
>> +    if (force_console_suspend_disable)
>> +        return -EINVAL;
>> +
>>       if (loss_cnt<  0) {
>>           dev_err(dev, "serial_omap_get_context_loss_count failed : %d\n",
>>               loss_cnt);

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diff mbox

Patch

diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index f660156..427c407 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -51,7 +51,7 @@ 
  #define DEFAULT_AUTOSUSPEND_DELAY    -1

  #define MAX_UART_HWMOD_NAME_LEN        16
-
+int force_console_suspend_disable;
  struct omap_uart_state {
      int num;

@@ -207,8 +207,10 @@  static int __init omap_serial_early_init(void)
                      uart_name, uart->num);
              }

-            if (cmdline_find_option("no_console_suspend"))
+            if (cmdline_find_option("no_console_suspend")) {
+                force_console_suspend_disable = 1;
                  no_console_suspend = true;
+            }

              /*
               * omap-uart can be used for earlyprintk logs
diff --git a/drivers/tty/serial/omap-serial.c 
b/drivers/tty/serial/omap-serial.c
index 08332f3..395ade8 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -43,6 +43,7 @@ 
  #include <linux/pinctrl/consumer.h>
  #include <linux/platform_data/serial-omap.h>

+extern int force_console_suspend_disable;
  #define OMAP_MAX_HSUART_PORTS    6

  #define UART_BUILD_REVISION(x, y)    (((x) << 8) | (y))
@@ -1582,7 +1583,7 @@  static int serial_omap_runtime_suspend(struct 
device *dev)
      struct uart_omap_port *up = dev_get_drvdata(dev);
      struct omap_uart_port_info *pdata = dev->platform_data;

-    if (!up)
+    if (!up || force_console_suspend_disable)
          return -EINVAL;