[v2,02/22] vga_switcheroo: Add helper function to get the active client

Commit Message

Lukas Wunner Sept. 7, 2012, 3:22 p.m. UTC

From: Seth Forshee <[e-mail]>

Add vga_switcheroo_get_active_client() to allow drivers to get the
active video client. This will be used by drivers wishing to temporarily
mux only the DDC to the inactive client.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88861
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=61115
Tested-by: Paul Hordiienko <[e-mail]>
    [MBP  6,2 2010  intel ILK + nvidia GT216  pre-retina]
Tested-by: William Brown <[e-mail]>
    [MBP  8,2 2011  intel SNB + amd turks     pre-retina]
Tested-by: Lukas Wunner <[e-mail]>
    [MBP  9,1 2012  intel IVB + nvidia GK107  pre-retina]
Tested-by: Bruno Bierbaumer <[e-mail]>
    [MBP 11,3 2013  intel HSW + nvidia GK107  retina -- work in progress]

Signed-off-by: Seth Forshee <[e-mail]>
Signed-off-by: Dave Airlie <[e-mail]>
Signed-off-by: Lukas Wunner <[e-mail]>
---
 drivers/gpu/vga/vga_switcheroo.c | 14 ++++++++++++++
 include/linux/vga_switcheroo.h   |  2 ++
 2 files changed, 16 insertions(+)

Patch

diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
index 0d3ac20..620c4ac 100644
--- a/drivers/gpu/vga/vga_switcheroo.c
+++ b/drivers/gpu/vga/vga_switcheroo.c
@@ -209,6 +209,20 @@  find_active_client(struct list_head *head)
 	return NULL;
 }
 
+struct pci_dev *vga_switcheroo_get_active_client(void)
+{
+	struct vga_switcheroo_client *client;
+	struct pci_dev *pdev = NULL;
+
+	mutex_lock(&vgasr_mutex);
+	client = find_active_client(&vgasr_priv.clients);
+	if (client)
+		pdev = client->pdev;
+	mutex_unlock(&vgasr_mutex);
+	return pdev;
+}
+EXPORT_SYMBOL(vga_switcheroo_get_active_client);
+
 int vga_switcheroo_get_client_state(struct pci_dev *pdev)
 {
 	struct vga_switcheroo_client *client;
diff --git a/include/linux/vga_switcheroo.h b/include/linux/vga_switcheroo.h
index 2fef78b..c81a686 100644
--- a/include/linux/vga_switcheroo.h
+++ b/include/linux/vga_switcheroo.h
@@ -62,6 +62,7 @@  void vga_switcheroo_unregister_handler(void);
 
 int vga_switcheroo_process_delayed_switch(void);
 
+struct pci_dev *vga_switcheroo_get_active_client(void);
 int vga_switcheroo_get_client_state(struct pci_dev *dev);
 
 void vga_switcheroo_set_dynamic_switch(struct pci_dev *pdev, enum vga_switcheroo_state dynamic);
@@ -82,6 +83,7 @@  static inline int vga_switcheroo_register_audio_client(struct pci_dev *pdev,
 	int id, bool active) { return 0; }
 static inline void vga_switcheroo_unregister_handler(void) {}
 static inline int vga_switcheroo_process_delayed_switch(void) { return 0; }
+static inline struct pci_dev *vga_switcheroo_get_active_client(void) { return NULL; }
 static inline int vga_switcheroo_get_client_state(struct pci_dev *dev) { return VGA_SWITCHEROO_ON; }
 
 static inline void vga_switcheroo_set_dynamic_switch(struct pci_dev *pdev, enum vga_switcheroo_state dynamic) {}