[PATCH] ACPI / PM: Fix error message in __acpi_bus_set_power()

[PATCH] ACPI / PM: Fix error message in __acpi_bus_set_power()

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rjw@sisk.pl>

After recent changes of the ACPI device low-power states definitions
an error message in __acpi_bus_set_power() needs to be updated so
that it prints the correct name of the state that has been requested
(currently it will print "D3" for D3hot and "D4" for D3cold).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
 drivers/acpi/bus.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Index: linux/drivers/acpi/bus.c
===================================================================
--- linux.orig/drivers/acpi/bus.c
+++ linux/drivers/acpi/bus.c
@@ -240,7 +240,9 @@ static int __acpi_bus_set_power(struct a
 	}
 
 	if (!device->power.states[state].flags.valid) {
-		printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
+		printk(KERN_WARNING PREFIX "Device does not support D%d%s\n",
+			state == ACPI_STATE_D3_COLD ? 3 : state,
+			state == ACPI_STATE_D3_HOT ? "hot" : "");
 		return -ENODEV;
 	}
 	if (device->parent && (state < device->parent->power.state)) {

Re: [PATCH] ACPI / PM: Fix error message in __acpi_bus_set_power()

[Rafael J. Wysocki]

On Monday, May 14, 2012, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rjw@sisk.pl>
> 
> After recent changes of the ACPI device low-power states definitions
> an error message in __acpi_bus_set_power() needs to be updated so
> that it prints the correct name of the state that has been requested
> (currently it will print "D3" for D3hot and "D4" for D3cold).

Please disregard this patch, I'll send a better one in a little while.

Thanks,
Rafael


> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> ---
>  drivers/acpi/bus.c |    4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> Index: linux/drivers/acpi/bus.c
> ===================================================================
> --- linux.orig/drivers/acpi/bus.c
> +++ linux/drivers/acpi/bus.c
> @@ -240,7 +240,9 @@ static int __acpi_bus_set_power(struct a
>  	}
>  
>  	if (!device->power.states[state].flags.valid) {
> -		printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
> +		printk(KERN_WARNING PREFIX "Device does not support D%d%s\n",
> +			state == ACPI_STATE_D3_COLD ? 3 : state,
> +			state == ACPI_STATE_D3_HOT ? "hot" : "");
>  		return -ENODEV;
>  	}
>  	if (device->parent && (state < device->parent->power.state)) {
> --
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> 

[PATCH 0/2] ACPI / PM: Fixes related to new definitions of device power states

[Rafael J. Wysocki]

Hi,

The following two patches fix a couple of remaining issues that appeared
when the definitions of ACPI device power states were changed.

[1/2] - Fix messages printing power states in drivers/acpi/bus.c.
[2/2] - Fix the reading of device power states.

Thanks,
Rafael

[PATCH 1/2] ACPI / PM: Fix error messages in drivers/acpi/bus.c

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rjw@sisk.pl>

After recent changes of the ACPI device low-power states definitions
kernel messages in drivers/acpi/bus.c need to be updated so that they
include the correct names of the states in question (currently that
is "D3" for D3hot and "D4" for D3cold, which is incorrect).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
 drivers/acpi/bus.c |   37 ++++++++++++++++++++++++++++---------
 1 file changed, 28 insertions(+), 9 deletions(-)

Index: linux/drivers/acpi/bus.c
===================================================================
--- linux.orig/drivers/acpi/bus.c
+++ linux/drivers/acpi/bus.c
@@ -182,6 +182,24 @@ EXPORT_SYMBOL(acpi_bus_get_private_data)
                                  Power Management
    -------------------------------------------------------------------------- */
 
+static char *state_string(int state)
+{
+	switch (state) {
+	case ACPI_STATE_D0:
+		return "D0";
+	case ACPI_STATE_D1:
+		return "D1";
+	case ACPI_STATE_D2:
+		return "D2";
+	case ACPI_STATE_D3_HOT:
+		return "D3hot";
+	case ACPI_STATE_D3_COLD:
+		return "D3";
+	default:
+		return "(unknown)";
+	}
+}
+
 static int __acpi_bus_get_power(struct acpi_device *device, int *state)
 {
 	int result = 0;
@@ -215,8 +233,8 @@ static int __acpi_bus_get_power(struct a
 			device->parent->power.state : ACPI_STATE_D0;
 	}
 
-	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
-			  device->pnp.bus_id, *state));
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
+			  device->pnp.bus_id, state_string(*state)));
 
 	return 0;
 }
@@ -234,13 +252,14 @@ static int __acpi_bus_set_power(struct a
 	/* Make sure this is a valid target state */
 
 	if (state == device->power.state) {
-		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
-				  state));
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at %s\n",
+				  state_string(state)));
 		return 0;
 	}
 
 	if (!device->power.states[state].flags.valid) {
-		printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
+		printk(KERN_WARNING PREFIX "Device does not support %s\n",
+		       state_string(state));
 		return -ENODEV;
 	}
 	if (device->parent && (state < device->parent->power.state)) {
@@ -294,13 +313,13 @@ static int __acpi_bus_set_power(struct a
       end:
 	if (result)
 		printk(KERN_WARNING PREFIX
-			      "Device [%s] failed to transition to D%d\n",
-			      device->pnp.bus_id, state);
+			      "Device [%s] failed to transition to %s\n",
+			      device->pnp.bus_id, state_string(state));
 	else {
 		device->power.state = state;
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-				  "Device [%s] transitioned to D%d\n",
-				  device->pnp.bus_id, state));
+				  "Device [%s] transitioned to %s\n",
+				  device->pnp.bus_id, state_string(state)));
 	}
 
 	return result;

[PATCH 2/2] ACPI / PM: Make __acpi_bus_get_power() cover D3cold correctly

[Rafael J. Wysocki]

From: Rafael J. Wysocki <rjw@sisk.pl>

After recent changes of the ACPI device power states definitions, if
power resources are not used for the device's power management, the
state returned by __acpi_bus_get_power() cannot exceed D3hot, because
the return values of _PSC are 0 through 3.  However, if the _PR3
method is not present for the device and _PS3 returns 3, we have to
assume that the device is in D3cold, so the value returned by
__acpi_bus_get_power() in that case should be 4.

Similarly, acpi_power_get_inferred_state() should take the power
resources for the D3hot state into account in general, so that it
can return 3 if those resources are "on" or 4 (D3cold) otherwise.

Fix the the above two issues and make sure that if both _PSC and
_PR3 are present for the device, the power resources listed by _PR3
will be used to determine if the number 3 returned by _PSC is meant
to represent D3cold or D3hot.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
 drivers/acpi/bus.c   |   51 +++++++++++++++++++++++++++++----------------------
 drivers/acpi/power.c |    2 +-
 2 files changed, 30 insertions(+), 23 deletions(-)

Index: linux/drivers/acpi/bus.c
===================================================================
--- linux.orig/drivers/acpi/bus.c
+++ linux/drivers/acpi/bus.c
@@ -202,37 +202,44 @@ static char *state_string(int state)
 
 static int __acpi_bus_get_power(struct acpi_device *device, int *state)
 {
-	int result = 0;
-	acpi_status status = 0;
-	unsigned long long psc = 0;
+	int result = ACPI_STATE_UNKNOWN;
 
 	if (!device || !state)
 		return -EINVAL;
 
-	*state = ACPI_STATE_UNKNOWN;
-
-	if (device->flags.power_manageable) {
-		/*
-		 * Get the device's power state either directly (via _PSC) or
-		 * indirectly (via power resources).
-		 */
-		if (device->power.flags.power_resources) {
-			result = acpi_power_get_inferred_state(device, state);
-			if (result)
-				return result;
-		} else if (device->power.flags.explicit_get) {
-			status = acpi_evaluate_integer(device->handle, "_PSC",
-						       NULL, &psc);
-			if (ACPI_FAILURE(status))
-				return -ENODEV;
-			*state = (int)psc;
-		}
-	} else {
+	if (!device->flags.power_manageable) {
 		/* TBD: Non-recursive algorithm for walking up hierarchy. */
 		*state = device->parent ?
 			device->parent->power.state : ACPI_STATE_D0;
+		goto out;
+	}
+
+	/*
+	 * Get the device's power state either directly (via _PSC) or
+	 * indirectly (via power resources).
+	 */
+	if (device->power.flags.explicit_get) {
+		unsigned long long psc;
+		acpi_status status = acpi_evaluate_integer(device->handle,
+							   "_PSC", NULL, &psc);
+		if (ACPI_FAILURE(status))
+			return -ENODEV;
+
+		result = psc;
+	}
+	/* The test below covers ACPI_STATE_UNKNOWN too. */
+	if (result <= ACPI_STATE_D2) {
+	  ; /* Do nothing. */
+	} else if (device->power.flags.power_resources) {
+		int error = acpi_power_get_inferred_state(device, &result);
+		if (error)
+			return error;
+	} else if (result == ACPI_STATE_D3_HOT) {
+		result = ACPI_STATE_D3;
 	}
+	*state = result;
 
+ out:
 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
 			  device->pnp.bus_id, state_string(*state)));
 
Index: linux/drivers/acpi/power.c
===================================================================
--- linux.orig/drivers/acpi/power.c
+++ linux/drivers/acpi/power.c
@@ -631,7 +631,7 @@ int acpi_power_get_inferred_state(struct
 	 * We know a device's inferred power state when all the resources
 	 * required for a given D-state are 'on'.
 	 */
-	for (i = ACPI_STATE_D0; i < ACPI_STATE_D3_HOT; i++) {
+	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
 		list = &device->power.states[i].resources;
 		if (list->count < 1)
 			continue;

Re: [PATCH 1/2] ACPI / PM: Fix error messages in drivers/acpi/bus.c

[Andreas Mohr]

Hi,

> --- linux.orig/drivers/acpi/bus.c
> +++ linux/drivers/acpi/bus.c
> @@ -182,6 +182,24 @@ EXPORT_SYMBOL(acpi_bus_get_private_data)
>                                   Power Management
>     -------------------------------------------------------------------------- */
>  
> +static char *state_string(int state)
> +{
> +	switch (state) {
> +	case ACPI_STATE_D0:
> +		return "D0";
> +	case ACPI_STATE_D1:
> +		return "D1";

"const char", please?

In general: nice work, thanks!

Andreas Mohr

Re: [PATCH 1/2] ACPI / PM: Fix error messages in drivers/acpi/bus.c

[Rafael J. Wysocki]

On Sunday, May 20, 2012, Andreas Mohr wrote:
> Hi,
> 
> > --- linux.orig/drivers/acpi/bus.c
> > +++ linux/drivers/acpi/bus.c
> > @@ -182,6 +182,24 @@ EXPORT_SYMBOL(acpi_bus_get_private_data)
> >                                   Power Management
> >     -------------------------------------------------------------------------- */
> >  
> > +static char *state_string(int state)
> > +{
> > +	switch (state) {
> > +	case ACPI_STATE_D0:
> > +		return "D0";
> > +	case ACPI_STATE_D1:
> > +		return "D1";
> 
> "const char", please?

Sure, appended.

I don't think it makes much difference, though.  In case it does, please feel
free to post a patch changing pm_verb() along this line.

> In general: nice work, thanks!

Well, thanks! :-)

---
From: Rafael J. Wysocki <rjw@sisk.pl>
Subject: ACPI / PM: Fix error messages in drivers/acpi/bus.c

After recent changes of the ACPI device low-power states definitions
kernel messages in drivers/acpi/bus.c need to be updated so that they
include the correct names of the states in question (currently is
"D3" for D3hot and "D4" for D3cold, which is incorrect).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
 drivers/acpi/bus.c |   37 ++++++++++++++++++++++++++++---------
 1 file changed, 28 insertions(+), 9 deletions(-)

Index: linux/drivers/acpi/bus.c
===================================================================
--- linux.orig/drivers/acpi/bus.c
+++ linux/drivers/acpi/bus.c
@@ -182,6 +182,24 @@ EXPORT_SYMBOL(acpi_bus_get_private_data)
                                  Power Management
    -------------------------------------------------------------------------- */
 
+static const char *state_string(int state)
+{
+	switch (state) {
+	case ACPI_STATE_D0:
+		return "D0";
+	case ACPI_STATE_D1:
+		return "D1";
+	case ACPI_STATE_D2:
+		return "D2";
+	case ACPI_STATE_D3_HOT:
+		return "D3hot";
+	case ACPI_STATE_D3_COLD:
+		return "D3";
+	default:
+		return "(unknown)";
+	}
+}
+
 static int __acpi_bus_get_power(struct acpi_device *device, int *state)
 {
 	int result = 0;
@@ -215,8 +233,8 @@ static int __acpi_bus_get_power(struct a
 			device->parent->power.state : ACPI_STATE_D0;
 	}
 
-	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is D%d\n",
-			  device->pnp.bus_id, *state));
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
+			  device->pnp.bus_id, state_string(*state)));
 
 	return 0;
 }
@@ -234,13 +252,14 @@ static int __acpi_bus_set_power(struct a
 	/* Make sure this is a valid target state */
 
 	if (state == device->power.state) {
-		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at D%d\n",
-				  state));
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at %s\n",
+				  state_string(state)));
 		return 0;
 	}
 
 	if (!device->power.states[state].flags.valid) {
-		printk(KERN_WARNING PREFIX "Device does not support D%d\n", state);
+		printk(KERN_WARNING PREFIX "Device does not support %s\n",
+		       state_string(state));
 		return -ENODEV;
 	}
 	if (device->parent && (state < device->parent->power.state)) {
@@ -294,13 +313,13 @@ static int __acpi_bus_set_power(struct a
       end:
 	if (result)
 		printk(KERN_WARNING PREFIX
-			      "Device [%s] failed to transition to D%d\n",
-			      device->pnp.bus_id, state);
+			      "Device [%s] failed to transition to %s\n",
+			      device->pnp.bus_id, state_string(state));
 	else {
 		device->power.state = state;
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-				  "Device [%s] transitioned to D%d\n",
-				  device->pnp.bus_id, state));
+				  "Device [%s] transitioned to %s\n",
+				  device->pnp.bus_id, state_string(state)));
 	}
 
 	return result;