[PATCH 4.14 154/190] vga_switcheroo: Deduplicate power state tracking

Greg Kroah-Hartman
2020-06-19T16:33:50Z

From: Lukas Wunner <lukas@wunner.de>

[ Upstream commit 8948ca1a12c9a039361bbc3e4627064153971d57 ]

If DRM drivers use runtime PM, they currently notify vga_switcheroo
whenever they ->runtime_suspend or ->runtime_resume to update
vga_switcheroo's internal power state tracking.

That's essentially a duplication of a functionality performed by the
PM core as it already tracks the GPU's power state and vga_switcheroo
can always query it.

Introduce a new internal helper vga_switcheroo_pwr_state() which does
just that if runtime PM is used, or falls back to vga_switcheroo's
internal power state tracking if manual power control is used.
Drop a redundant power state check in set_audio_state() while at it.

This removes one of the two purposes of the notification mechanism
implemented by vga_switcheroo_set_dynamic_switch(). The other one is
power management of the audio device and we'll remove that next.

Cc: Dave Airlie <airlied@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Peter Wu <peter@lekensteyn.nl>
Tested-by: Kai Heng Feng <kai.heng.feng@canonical.com> # AMD PowerXpress
Tested-by: Mike Lothian <mike@fireburn.co.uk> # AMD PowerXpress
Tested-by: Denis Lisov <dennis.lissov@gmail.com> # Nvidia Optimus
Tested-by: Peter Wu <peter@lekensteyn.nl> # Nvidia Optimus
Tested-by: Lukas Wunner <lukas@wunner.de> # MacBook Pro
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://patchwork.freedesktop.org/patch/msgid/0aa49d735b988aa04524a8dc339582ace33f0f94.1520068884.git.lukas@wunner.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/vga/vga_switcheroo.c | 35 +++++++++++++++++++++-----------
1 file changed, 23 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
index 3cd153c6d271..5da45325621c 100644
--- a/drivers/gpu/vga/vga_switcheroo.c
+++ b/drivers/gpu/vga/vga_switcheroo.c
@@ -92,7 +92,8 @@
* struct vga_switcheroo_client - registered client
* @pdev: client pci device
* @fb_info: framebuffer to which console is remapped on switching
- * @pwr_state: current power state
+ * @pwr_state: current power state if manual power control is used.
+ * For driver power control, call vga_switcheroo_pwr_state().
* @ops: client callbacks
* @id: client identifier. Determining the id requires the handler,
* so gpus are initially assigned VGA_SWITCHEROO_UNKNOWN_ID
@@ -406,6 +407,19 @@ bool vga_switcheroo_client_probe_defer(struct pci_dev *pdev)
}
EXPORT_SYMBOL(vga_switcheroo_client_probe_defer);

+static enum vga_switcheroo_state
+vga_switcheroo_pwr_state(struct vga_switcheroo_client *client)
+{
+ if (client->driver_power_control)
+ if (pm_runtime_enabled(&client->pdev->dev) &&
+ pm_runtime_active(&client->pdev->dev))
+ return VGA_SWITCHEROO_ON;
+ else
+ return VGA_SWITCHEROO_OFF;
+ else
+ return client->pwr_state;
+}
+
/**
* vga_switcheroo_get_client_state() - obtain power state of a given client
* @pdev: client pci device
@@ -425,7 +439,7 @@ enum vga_switcheroo_state vga_switcheroo_get_client_state(struct pci_dev *pdev)
if (!client)
ret = VGA_SWITCHEROO_NOT_FOUND;
else
- ret = client->pwr_state;
+ ret = vga_switcheroo_pwr_state(client);
mutex_unlock(&vgasr_mutex);
return ret;
}
@@ -598,7 +612,7 @@ static int vga_switcheroo_show(struct seq_file *m, void *v)
client_is_vga(client) ? "" : "-Audio",
client->active ? '+' : ' ',
client->driver_power_control ? "Dyn" : "",
- client->pwr_state ? "Pwr" : "Off",
+ vga_switcheroo_pwr_state(client) ? "Pwr" : "Off",
pci_name(client->pdev));
i++;
}
@@ -641,7 +655,7 @@ static void set_audio_state(enum vga_switcheroo_client_id id,
struct vga_switcheroo_client *client;

client = find_client_from_id(&vgasr_priv.clients, id | ID_BIT_AUDIO);
- if (client && client->pwr_state != state) {
+ if (client) {
client->ops->set_gpu_state(client->pdev, state);
client->pwr_state = state;
}
@@ -656,7 +670,7 @@ static int vga_switchto_stage1(struct vga_switcheroo_client *new_client)
if (!active)
return 0;

- if (new_client->pwr_state == VGA_SWITCHEROO_OFF)
+ if (vga_switcheroo_pwr_state(new_client) == VGA_SWITCHEROO_OFF)
vga_switchon(new_client);

vga_set_default_device(new_client->pdev);
@@ -695,7 +709,7 @@ static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
if (new_client->ops->reprobe)
new_client->ops->reprobe(new_client->pdev);

- if (active->pwr_state == VGA_SWITCHEROO_ON)
+ if (vga_switcheroo_pwr_state(active) == VGA_SWITCHEROO_ON)
vga_switchoff(active);

set_audio_state(new_client->id, VGA_SWITCHEROO_ON);
@@ -940,8 +954,7 @@ EXPORT_SYMBOL(vga_switcheroo_process_delayed_switch);
* command line disables it.
*
* When the driver decides to power up or down, it notifies vga_switcheroo
- * thereof so that it can (a) power the audio device on the GPU up or down,
- * and (b) update its internal power state representation for the device.
+ * thereof so that it can power the audio device on the GPU up or down.
* This is achieved by vga_switcheroo_set_dynamic_switch().
*
* After the GPU has been suspended, the handler needs to be called to cut
@@ -985,9 +998,8 @@ static void vga_switcheroo_power_switch(struct pci_dev *pdev,
*
* Helper for GPUs whose power state is controlled by the driver's runtime pm.
* When the driver decides to power up or down, it notifies vga_switcheroo
- * thereof using this helper so that it can (a) power the audio device on
- * the GPU up or down, and (b) update its internal power state representation
- * for the device.
+ * thereof using this helper so that it can power the audio device on the GPU
+ * up or down.
*/
void vga_switcheroo_set_dynamic_switch(struct pci_dev *pdev,
enum vga_switcheroo_state dynamic)
@@ -1001,7 +1013,6 @@ void vga_switcheroo_set_dynamic_switch(struct pci_dev *pdev,
return;
}

- client->pwr_state = dynamic;
set_audio_state(client->id, dynamic);
mutex_unlock(&vgasr_mutex);
}
--
2.25.1