power: supply: sbs-battery: only return health when battery present
diff mbox series

Message ID 20190816075842.27333-1-committed@heine.so
State Not Applicable, archived
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  • power: supply: sbs-battery: only return health when battery present
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Commit Message

Michael Nosthoff Aug. 16, 2019, 7:58 a.m. UTC
when the battery is set to sbs-mode and  no gpio detection is enabled
"health" is always returning a value even when the battery is not present.
All other fields return "not present".
This leads to a scenario where the driver is constantly switching between
"present" and "not present" state. This generates a lot of constant
traffic on the i2c.

This commit changes the response of "health" to an error when the battery
is not responding leading to a consistent "not present" state.

Fixes: 76b16f4cdfb8 ("power: supply: sbs-battery: don't assume
MANUFACTURER_DATA formats")

Signed-off-by: Michael Nosthoff <committed@heine.so>
Cc: Brian Norris <briannorris@chromium.org>
Cc: <stable@vger.kernel.org>
---
 drivers/power/supply/sbs-battery.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

Comments

Brian Norris Aug. 22, 2019, 1:46 a.m. UTC | #1
On Fri, Aug 16, 2019 at 09:58:42AM +0200, Michael Nosthoff wrote:
> when the battery is set to sbs-mode and  no gpio detection is enabled
> "health" is always returning a value even when the battery is not present.
> All other fields return "not present".
> This leads to a scenario where the driver is constantly switching between
> "present" and "not present" state. This generates a lot of constant
> traffic on the i2c.

That depends on how often you're checking the "health" attribute,
doesn't it? But anyway, the bug is real.

> This commit changes the response of "health" to an error when the battery
> is not responding leading to a consistent "not present" state.

Ack, and thanks for the fix.

> Fixes: 76b16f4cdfb8 ("power: supply: sbs-battery: don't assume
> MANUFACTURER_DATA formats")
> 
> Signed-off-by: Michael Nosthoff <committed@heine.so>
> Cc: Brian Norris <briannorris@chromium.org>
> Cc: <stable@vger.kernel.org>

Reviewed-by: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>

> ---
>  drivers/power/supply/sbs-battery.c | 25 ++++++++++++++++---------
>  1 file changed, 16 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c
> index 2e86cc1e0e35..f8d74e9f7931 100644
> --- a/drivers/power/supply/sbs-battery.c
> +++ b/drivers/power/supply/sbs-battery.c
> @@ -314,17 +314,22 @@ static int sbs_get_battery_presence_and_health(
>  {
>  	int ret;
>  
> -	if (psp == POWER_SUPPLY_PROP_PRESENT) {
> -		/* Dummy command; if it succeeds, battery is present. */
> -		ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
> -		if (ret < 0)
> -			val->intval = 0; /* battery disconnected */
> -		else
> -			val->intval = 1; /* battery present */
> -	} else { /* POWER_SUPPLY_PROP_HEALTH */
> +	/* Dummy command; if it succeeds, battery is present. */
> +	ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
> +
> +	if (ret < 0) { /* battery not present*/
> +		if (psp == POWER_SUPPLY_PROP_PRESENT) {
> +			val->intval = 0;
> +			return 0;

Technically, you don't need the 'return 0' (and if we care about
symmetry: the TI version doesn't), since the caller knows that "not
present" will yield errors. I'm not sure which version makes more sense.

> +		}
> +		return ret;
> +	}
> +
> +	if (psp == POWER_SUPPLY_PROP_PRESENT)
> +		val->intval = 1; /* battery present */
> +	else /* POWER_SUPPLY_PROP_HEALTH */
>  		/* SBS spec doesn't have a general health command. */
>  		val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
> -	}
>  
>  	return 0;
>  }
> @@ -626,6 +631,8 @@ static int sbs_get_property(struct power_supply *psy,
>  		else
>  			ret = sbs_get_battery_presence_and_health(client, psp,
>  								  val);
> +
> +		/* this can only be true if no gpio is used */
>  		if (psp == POWER_SUPPLY_PROP_PRESENT)
>  			return 0;
>  		break;
> -- 
> 2.20.1
>
Brian Norris Aug. 22, 2019, 1:48 a.m. UTC | #2
+ Sebastian

I'm not sure if he expects to be on the To/Cc, but that usually is the
way to get a maintainer to take your patch.

Brian

On Wed, Aug 21, 2019 at 06:46:55PM -0700, Brian Norris wrote:
> On Fri, Aug 16, 2019 at 09:58:42AM +0200, Michael Nosthoff wrote:
> > when the battery is set to sbs-mode and  no gpio detection is enabled
> > "health" is always returning a value even when the battery is not present.
> > All other fields return "not present".
> > This leads to a scenario where the driver is constantly switching between
> > "present" and "not present" state. This generates a lot of constant
> > traffic on the i2c.
> 
> That depends on how often you're checking the "health" attribute,
> doesn't it? But anyway, the bug is real.
> 
> > This commit changes the response of "health" to an error when the battery
> > is not responding leading to a consistent "not present" state.
> 
> Ack, and thanks for the fix.
> 
> > Fixes: 76b16f4cdfb8 ("power: supply: sbs-battery: don't assume
> > MANUFACTURER_DATA formats")
> > 
> > Signed-off-by: Michael Nosthoff <committed@heine.so>
> > Cc: Brian Norris <briannorris@chromium.org>
> > Cc: <stable@vger.kernel.org>
> 
> Reviewed-by: Brian Norris <briannorris@chromium.org>
> Tested-by: Brian Norris <briannorris@chromium.org>
> 
> > ---
> >  drivers/power/supply/sbs-battery.c | 25 ++++++++++++++++---------
> >  1 file changed, 16 insertions(+), 9 deletions(-)
> > 
> > diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c
> > index 2e86cc1e0e35..f8d74e9f7931 100644
> > --- a/drivers/power/supply/sbs-battery.c
> > +++ b/drivers/power/supply/sbs-battery.c
> > @@ -314,17 +314,22 @@ static int sbs_get_battery_presence_and_health(
> >  {
> >  	int ret;
> >  
> > -	if (psp == POWER_SUPPLY_PROP_PRESENT) {
> > -		/* Dummy command; if it succeeds, battery is present. */
> > -		ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
> > -		if (ret < 0)
> > -			val->intval = 0; /* battery disconnected */
> > -		else
> > -			val->intval = 1; /* battery present */
> > -	} else { /* POWER_SUPPLY_PROP_HEALTH */
> > +	/* Dummy command; if it succeeds, battery is present. */
> > +	ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
> > +
> > +	if (ret < 0) { /* battery not present*/
> > +		if (psp == POWER_SUPPLY_PROP_PRESENT) {
> > +			val->intval = 0;
> > +			return 0;
> 
> Technically, you don't need the 'return 0' (and if we care about
> symmetry: the TI version doesn't), since the caller knows that "not
> present" will yield errors. I'm not sure which version makes more sense.
> 
> > +		}
> > +		return ret;
> > +	}
> > +
> > +	if (psp == POWER_SUPPLY_PROP_PRESENT)
> > +		val->intval = 1; /* battery present */
> > +	else /* POWER_SUPPLY_PROP_HEALTH */
> >  		/* SBS spec doesn't have a general health command. */
> >  		val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
> > -	}
> >  
> >  	return 0;
> >  }
> > @@ -626,6 +631,8 @@ static int sbs_get_property(struct power_supply *psy,
> >  		else
> >  			ret = sbs_get_battery_presence_and_health(client, psp,
> >  								  val);
> > +
> > +		/* this can only be true if no gpio is used */
> >  		if (psp == POWER_SUPPLY_PROP_PRESENT)
> >  			return 0;
> >  		break;
> > -- 
> > 2.20.1
> >
Michael Nosthoff Aug. 22, 2019, 7:43 a.m. UTC | #3
Brian Norris wrote:
> On Fri, Aug 16, 2019 at 09:58:42AM +0200, Michael Nosthoff wrote:
>> when the battery is set to sbs-mode and  no gpio detection is enabled
>> "health" is always returning a value even when the battery is not present.
>> All other fields return "not present".
>> This leads to a scenario where the driver is constantly switching between
>> "present" and "not present" state. This generates a lot of constant
>> traffic on the i2c.
>
> That depends on how often you're checking the "health" attribute,
> doesn't it? But anyway, the bug is real.
At least on my Hardware I had constant traffic from the moment the 
device was probed.
I have no userland process accessing the device.
I'm guessing that it has something todo with the call to 
'power_supply_changed'.
This done at the end of 'sbs_get_property' if the presence state changed and
no gpio is used. I suspect it triggers a readout of all the properties 
and leads to this
endless loop?
>> This commit changes the response of "health" to an error when the battery
>> is not responding leading to a consistent "not present" state.
>
> Ack, and thanks for the fix.
>
>> Fixes: 76b16f4cdfb8 ("power: supply: sbs-battery: don't assume
>> MANUFACTURER_DATA formats")
>>
>> Signed-off-by: Michael Nosthoff<committed@heine.so>
>> Cc: Brian Norris<briannorris@chromium.org>
>> Cc:<stable@vger.kernel.org>
>
> Reviewed-by: Brian Norris<briannorris@chromium.org>
> Tested-by: Brian Norris<briannorris@chromium.org>
thanks for review!
>
>> ---
>>   drivers/power/supply/sbs-battery.c | 25 ++++++++++++++++---------
>>   1 file changed, 16 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c
>> index 2e86cc1e0e35..f8d74e9f7931 100644
>> --- a/drivers/power/supply/sbs-battery.c
>> +++ b/drivers/power/supply/sbs-battery.c
>> @@ -314,17 +314,22 @@ static int sbs_get_battery_presence_and_health(
>>   {
>>   	int ret;
>>
>> -	if (psp == POWER_SUPPLY_PROP_PRESENT) {
>> -		/* Dummy command; if it succeeds, battery is present. */
>> -		ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
>> -		if (ret<  0)
>> -			val->intval = 0; /* battery disconnected */
>> -		else
>> -			val->intval = 1; /* battery present */
>> -	} else { /* POWER_SUPPLY_PROP_HEALTH */
>> +	/* Dummy command; if it succeeds, battery is present. */
>> +	ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
>> +
>> +	if (ret<  0) { /* battery not present*/
>> +		if (psp == POWER_SUPPLY_PROP_PRESENT) {
>> +			val->intval = 0;
>> +			return 0;
>
> Technically, you don't need the 'return 0' (and if we care about
> symmetry: the TI version doesn't), since the caller knows that "not
> present" will yield errors. I'm not sure which version makes more sense.
>
>> +		}
>> +		return ret;
>> +	}
>> +
>> +	if (psp == POWER_SUPPLY_PROP_PRESENT)
>> +		val->intval = 1; /* battery present */
>> +	else /* POWER_SUPPLY_PROP_HEALTH */
>>   		/* SBS spec doesn't have a general health command. */
>>   		val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
>> -	}
>>
>>   	return 0;
>>   }
>> @@ -626,6 +631,8 @@ static int sbs_get_property(struct power_supply *psy,
>>   		else
>>   			ret = sbs_get_battery_presence_and_health(client, psp,
>>   								  val);
>> +
>> +		/* this can only be true if no gpio is used */
>>   		if (psp == POWER_SUPPLY_PROP_PRESENT)
>>   			return 0;
>>   		break;
>> -- 
>> 2.20.1
>>
Brian Norris Aug. 22, 2019, 8:32 p.m. UTC | #4
On Thu, Aug 22, 2019 at 12:43 AM Michael Nosthoff <committed@heine.so> wrote:
> This done at the end of 'sbs_get_property' if the presence state changed and
> no gpio is used. I suspect it triggers a readout of all the properties
> and leads to this
> endless loop?

Ah, it's not all properties IIUC, but it does lead to
power_supply_update_leds() -> power_supply_update_bat_leds() ->
power_supply_get_property(... POWER_SUPPLY_PROP_STATUS ...). That
would be enough to kick off the loop you're noticing.

Brian
Sebastian Reichel Sept. 2, 2019, 7:59 a.m. UTC | #5
Hi,

On Fri, Aug 16, 2019 at 09:58:42AM +0200, Michael Nosthoff wrote:
> when the battery is set to sbs-mode and  no gpio detection is enabled
> "health" is always returning a value even when the battery is not present.
> All other fields return "not present".
> This leads to a scenario where the driver is constantly switching between
> "present" and "not present" state. This generates a lot of constant
> traffic on the i2c.
> 
> This commit changes the response of "health" to an error when the battery
> is not responding leading to a consistent "not present" state.
> 
> Fixes: 76b16f4cdfb8 ("power: supply: sbs-battery: don't assume
> MANUFACTURER_DATA formats")
> 
> Signed-off-by: Michael Nosthoff <committed@heine.so>
> Cc: Brian Norris <briannorris@chromium.org>
> Cc: <stable@vger.kernel.org>
> ---

Thanks, queued.

-- Sebastian

>  drivers/power/supply/sbs-battery.c | 25 ++++++++++++++++---------
>  1 file changed, 16 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c
> index 2e86cc1e0e35..f8d74e9f7931 100644
> --- a/drivers/power/supply/sbs-battery.c
> +++ b/drivers/power/supply/sbs-battery.c
> @@ -314,17 +314,22 @@ static int sbs_get_battery_presence_and_health(
>  {
>  	int ret;
>  
> -	if (psp == POWER_SUPPLY_PROP_PRESENT) {
> -		/* Dummy command; if it succeeds, battery is present. */
> -		ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
> -		if (ret < 0)
> -			val->intval = 0; /* battery disconnected */
> -		else
> -			val->intval = 1; /* battery present */
> -	} else { /* POWER_SUPPLY_PROP_HEALTH */
> +	/* Dummy command; if it succeeds, battery is present. */
> +	ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
> +
> +	if (ret < 0) { /* battery not present*/
> +		if (psp == POWER_SUPPLY_PROP_PRESENT) {
> +			val->intval = 0;
> +			return 0;
> +		}
> +		return ret;
> +	}
> +
> +	if (psp == POWER_SUPPLY_PROP_PRESENT)
> +		val->intval = 1; /* battery present */
> +	else /* POWER_SUPPLY_PROP_HEALTH */
>  		/* SBS spec doesn't have a general health command. */
>  		val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
> -	}
>  
>  	return 0;
>  }
> @@ -626,6 +631,8 @@ static int sbs_get_property(struct power_supply *psy,
>  		else
>  			ret = sbs_get_battery_presence_and_health(client, psp,
>  								  val);
> +
> +		/* this can only be true if no gpio is used */
>  		if (psp == POWER_SUPPLY_PROP_PRESENT)
>  			return 0;
>  		break;
> -- 
> 2.20.1
>

Patch
diff mbox series

diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c
index 2e86cc1e0e35..f8d74e9f7931 100644
--- a/drivers/power/supply/sbs-battery.c
+++ b/drivers/power/supply/sbs-battery.c
@@ -314,17 +314,22 @@  static int sbs_get_battery_presence_and_health(
 {
 	int ret;
 
-	if (psp == POWER_SUPPLY_PROP_PRESENT) {
-		/* Dummy command; if it succeeds, battery is present. */
-		ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
-		if (ret < 0)
-			val->intval = 0; /* battery disconnected */
-		else
-			val->intval = 1; /* battery present */
-	} else { /* POWER_SUPPLY_PROP_HEALTH */
+	/* Dummy command; if it succeeds, battery is present. */
+	ret = sbs_read_word_data(client, sbs_data[REG_STATUS].addr);
+
+	if (ret < 0) { /* battery not present*/
+		if (psp == POWER_SUPPLY_PROP_PRESENT) {
+			val->intval = 0;
+			return 0;
+		}
+		return ret;
+	}
+
+	if (psp == POWER_SUPPLY_PROP_PRESENT)
+		val->intval = 1; /* battery present */
+	else /* POWER_SUPPLY_PROP_HEALTH */
 		/* SBS spec doesn't have a general health command. */
 		val->intval = POWER_SUPPLY_HEALTH_UNKNOWN;
-	}
 
 	return 0;
 }
@@ -626,6 +631,8 @@  static int sbs_get_property(struct power_supply *psy,
 		else
 			ret = sbs_get_battery_presence_and_health(client, psp,
 								  val);
+
+		/* this can only be true if no gpio is used */
 		if (psp == POWER_SUPPLY_PROP_PRESENT)
 			return 0;
 		break;