diff options
Diffstat (limited to 'drivers/gpu/vga')
| -rw-r--r-- | drivers/gpu/vga/vga_switcheroo.c | 62 |
1 files changed, 46 insertions, 16 deletions
diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c index cbd7c986d..5f962bfcb 100644 --- a/drivers/gpu/vga/vga_switcheroo.c +++ b/drivers/gpu/vga/vga_switcheroo.c @@ -30,6 +30,7 @@ #define pr_fmt(fmt) "vga_switcheroo: " fmt +#include <linux/apple-gmux.h> #include <linux/console.h> #include <linux/debugfs.h> #include <linux/fb.h> @@ -51,9 +52,9 @@ * * * muxed: Dual GPUs with a multiplexer chip to switch outputs between GPUs. * * muxless: Dual GPUs but only one of them is connected to outputs. - * The other one is merely used to offload rendering, its results - * are copied over PCIe into the framebuffer. On Linux this is - * supported with DRI PRIME. + * The other one is merely used to offload rendering, its results + * are copied over PCIe into the framebuffer. On Linux this is + * supported with DRI PRIME. * * Hybrid graphics started to appear in the late Naughties and were initially * all muxed. Newer laptops moved to a muxless architecture for cost reasons. @@ -308,7 +309,8 @@ static int register_client(struct pci_dev *pdev, * * Register vga client (GPU). Enable vga_switcheroo if another GPU and a * handler have already registered. The power state of the client is assumed - * to be ON. + * to be ON. Beforehand, vga_switcheroo_client_probe_defer() shall be called + * to ensure that all prerequisites are met. * * Return: 0 on success, -ENOMEM on memory allocation error. */ @@ -329,7 +331,8 @@ EXPORT_SYMBOL(vga_switcheroo_register_client); * @id: client identifier * * Register audio client (audio device on a GPU). The power state of the - * client is assumed to be ON. + * client is assumed to be ON. Beforehand, vga_switcheroo_client_probe_defer() + * shall be called to ensure that all prerequisites are met. * * Return: 0 on success, -ENOMEM on memory allocation error. */ @@ -376,6 +379,33 @@ find_active_client(struct list_head *head) } /** + * vga_switcheroo_client_probe_defer() - whether to defer probing a given client + * @pdev: client pci device + * + * Determine whether any prerequisites are not fulfilled to probe a given + * client. Drivers shall invoke this early on in their ->probe callback + * and return %-EPROBE_DEFER if it evaluates to %true. Thou shalt not + * register the client ere thou hast called this. + * + * Return: %true if probing should be deferred, otherwise %false. + */ +bool vga_switcheroo_client_probe_defer(struct pci_dev *pdev) +{ + if ((pdev->class >> 16) == PCI_BASE_CLASS_DISPLAY) { + /* + * apple-gmux is needed on pre-retina MacBook Pro + * to probe the panel if pdev is the inactive GPU. + */ + if (apple_gmux_present() && pdev != vga_default_device() && + !vgasr_priv.handler_flags) + return true; + } + + return false; +} +EXPORT_SYMBOL(vga_switcheroo_client_probe_defer); + +/** * vga_switcheroo_get_client_state() - obtain power state of a given client * @pdev: client pci device * @@ -530,21 +560,21 @@ EXPORT_SYMBOL(vga_switcheroo_unlock_ddc); * * OFF: Power off the device not in use. * * ON: Power on the device not in use. * * IGD: Switch to the integrated graphics device. - * Power on the integrated GPU if necessary, power off the discrete GPU. - * Prerequisite is that no user space processes (e.g. Xorg, alsactl) - * have opened device files of the GPUs or the audio client. If the - * switch fails, the user may invoke lsof(8) or fuser(1) on /dev/dri/ - * and /dev/snd/controlC1 to identify processes blocking the switch. + * Power on the integrated GPU if necessary, power off the discrete GPU. + * Prerequisite is that no user space processes (e.g. Xorg, alsactl) + * have opened device files of the GPUs or the audio client. If the + * switch fails, the user may invoke lsof(8) or fuser(1) on /dev/dri/ + * and /dev/snd/controlC1 to identify processes blocking the switch. * * DIS: Switch to the discrete graphics device. * * DIGD: Delayed switch to the integrated graphics device. - * This will perform the switch once the last user space process has - * closed the device files of the GPUs and the audio client. + * This will perform the switch once the last user space process has + * closed the device files of the GPUs and the audio client. * * DDIS: Delayed switch to the discrete graphics device. * * MIGD: Mux-only switch to the integrated graphics device. - * Does not remap console or change the power state of either gpu. - * If the integrated GPU is currently off, the screen will turn black. - * If it is on, the screen will show whatever happens to be in VRAM. - * Either way, the user has to blindly enter the command to switch back. + * Does not remap console or change the power state of either gpu. + * If the integrated GPU is currently off, the screen will turn black. + * If it is on, the screen will show whatever happens to be in VRAM. + * Either way, the user has to blindly enter the command to switch back. * * MDIS: Mux-only switch to the discrete graphics device. * * For GPUs whose power state is controlled by the driver's runtime pm, |