amdgpu/pm: remove code duplication in show_power_cap calls

 v3: updated patch to apply to latest code
 v2: reorder to check pointers before calling pm_runtime_* functions

 created generic function and call with enum from
 * amdgpu_hwmon_show_power_cap_max
 * amdgpu_hwmon_show_power_cap
 * amdgpu_hwmon_show_power_cap_default

=== Test ===
AMDGPU_PCI_ADDR=`lspci -nn | grep "VGA\|Display" | cut -d " " -f 1`
AMDGPU_HWMON=`ls -la /sys/class/hwmon | grep $AMDGPU_PCI_ADDR | cut -d " " -f 10`
HWMON_DIR=/sys/class/hwmon/${AMDGPU_HWMON}

cp pp_show_power_cap.txt{,.old}
lspci -nn | grep "VGA\|Display" > pp_show_power_cap.test.log
FILES="
power1_cap
power1_cap_max
power1_cap_default "

for f in $FILES
do
  echo  $f = `cat $HWMON_DIR/$f` >> pp_show_power_cap.test.log
done
Signed-off-by: Darren Powell <darren.powell@amd.com>
Reviewed-by: Kevin Wang <kevin1.wang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/pm/amdgpu_pm.c

@@ -2902,14 +2902,15 @@ static ssize_t amdgpu_hwmon_show_power_cap_min(struct device *dev,
 	return sprintf(buf, "%i\n", 0);
 }
 
-static ssize_t amdgpu_hwmon_show_power_cap_max(struct device *dev,
-					 struct device_attribute *attr,
-					 char *buf)
+
+static ssize_t amdgpu_hwmon_show_power_cap_generic(struct device *dev,
+					struct device_attribute *attr,
+					char *buf,
+					enum pp_power_limit_level pp_limit_level)
 {
 	struct amdgpu_device *adev = dev_get_drvdata(dev);
 	const struct amd_pm_funcs *pp_funcs = adev->powerplay.pp_funcs;
 	enum pp_power_type power_type = to_sensor_dev_attr(attr)->index;
-	enum pp_power_limit_level pp_limit_level = PP_PWR_LIMIT_MAX;
 	uint32_t limit;
 	ssize_t size;
 	int r;
@@ -2919,17 +2920,17 @@ static ssize_t amdgpu_hwmon_show_power_cap_max(struct device *dev,
 	if (adev->in_suspend && !adev->in_runpm)
 		return -EPERM;
 
+	if ( !(pp_funcs && pp_funcs->get_power_limit))
+		return -ENODATA;
+
 	r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
 	if (r < 0) {
 		pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
 		return r;
 	}
 
-	if (pp_funcs && pp_funcs->get_power_limit)
-		r = pp_funcs->get_power_limit(adev->powerplay.pp_handle, &limit,
-					      pp_limit_level, power_type);
-	else
-		r = -ENODATA;
+	r = pp_funcs->get_power_limit(adev->powerplay.pp_handle, &limit,
+				      pp_limit_level, power_type);
 
 	if (!r)
 		size = sysfs_emit(buf, "%u\n", limit * 1000000);
@@ -2942,85 +2943,31 @@ static ssize_t amdgpu_hwmon_show_power_cap_max(struct device *dev,
 	return size;
 }
 
-static ssize_t amdgpu_hwmon_show_power_cap(struct device *dev,
+
+static ssize_t amdgpu_hwmon_show_power_cap_max(struct device *dev,
 					 struct device_attribute *attr,
 					 char *buf)
 {
-	struct amdgpu_device *adev = dev_get_drvdata(dev);
-	const struct amd_pm_funcs *pp_funcs = adev->powerplay.pp_funcs;
-	enum pp_power_type power_type = to_sensor_dev_attr(attr)->index;
-	enum pp_power_limit_level pp_limit_level = PP_PWR_LIMIT_CURRENT;
-	uint32_t limit;
-	ssize_t size;
-	int r;
-
-	if (amdgpu_in_reset(adev))
-		return -EPERM;
-	if (adev->in_suspend && !adev->in_runpm)
-		return -EPERM;
-
-	r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
-	if (r < 0) {
-		pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
-		return r;
-	}
-
-	if (pp_funcs && pp_funcs->get_power_limit)
-		r = pp_funcs->get_power_limit(adev->powerplay.pp_handle, &limit,
-					      pp_limit_level, power_type);
-	else
-		r = -ENODATA;
+	return amdgpu_hwmon_show_power_cap_generic(dev, attr, buf, PP_PWR_LIMIT_MAX);
 
-	if (!r)
-		size = sysfs_emit(buf, "%u\n", limit * 1000000);
-	else
-		size = sysfs_emit(buf, "\n");
+}
 
-	pm_runtime_mark_last_busy(adev_to_drm(adev)->dev);
-	pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
+static ssize_t amdgpu_hwmon_show_power_cap(struct device *dev,
+					 struct device_attribute *attr,
+					 char *buf)
+{
+	return amdgpu_hwmon_show_power_cap_generic(dev, attr, buf, PP_PWR_LIMIT_CURRENT);
 
-	return size;
 }
 
 static ssize_t amdgpu_hwmon_show_power_cap_default(struct device *dev,
 					 struct device_attribute *attr,
 					 char *buf)
 {
-	struct amdgpu_device *adev = dev_get_drvdata(dev);
-	const struct amd_pm_funcs *pp_funcs = adev->powerplay.pp_funcs;
-	enum pp_power_type power_type = to_sensor_dev_attr(attr)->index;
-	enum pp_power_limit_level pp_limit_level = PP_PWR_LIMIT_DEFAULT;
-	uint32_t limit;
-	ssize_t size;
-	int r;
+	return amdgpu_hwmon_show_power_cap_generic(dev, attr, buf, PP_PWR_LIMIT_DEFAULT);
 
-	if (amdgpu_in_reset(adev))
-		return -EPERM;
-	if (adev->in_suspend && !adev->in_runpm)
-		return -EPERM;
-
-	r = pm_runtime_get_sync(adev_to_drm(adev)->dev);
-	if (r < 0) {
-		pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
-		return r;
-	}
-
-	if (pp_funcs && pp_funcs->get_power_limit)
-		r = pp_funcs->get_power_limit(adev->powerplay.pp_handle, &limit,
-					      pp_limit_level, power_type);
-	else
-		r = -ENODATA;
-
-	if (!r)
-		size = sysfs_emit(buf, "%u\n", limit * 1000000);
-	else
-		size = sysfs_emit(buf, "\n");
-
-	pm_runtime_mark_last_busy(adev_to_drm(adev)->dev);
-	pm_runtime_put_autosuspend(adev_to_drm(adev)->dev);
-
-	return size;
 }
+
 static ssize_t amdgpu_hwmon_show_power_label(struct device *dev,
 					 struct device_attribute *attr,
 					 char *buf)