d54a78f56444e79acb6b0f1d7ecbac30aef77385
[oweals/openwrt.git] /
1 From 124d768ec6f79f42bdcde24801e2315c4d2d7632 Mon Sep 17 00:00:00 2001
2 From: Jonathan Bell <jonathan@raspberrypi.org>
3 Date: Tue, 28 May 2019 13:56:06 +0100
4 Subject: [PATCH 623/703] drm: vc4: handle the case where there are no
5  available displays
6
7 It's reasonable for the firmware to return zero as the number of
8 attached displays. Handle this case as otherwise drm thinks that
9 the DSI panel is attached, which is nonsense.
10
11 Signed-off-by: Jonathan Bell <jonathan@raspberrypi.org>
12 ---
13  drivers/gpu/drm/vc4/vc4_firmware_kms.c | 32 +++++++++++++++-----------
14  1 file changed, 18 insertions(+), 14 deletions(-)
15
16 --- a/drivers/gpu/drm/vc4/vc4_firmware_kms.c
17 +++ b/drivers/gpu/drm/vc4/vc4_firmware_kms.c
18 @@ -1309,13 +1309,13 @@ static int vc4_fkms_bind(struct device *
19                                     RPI_FIRMWARE_FRAMEBUFFER_GET_NUM_DISPLAYS,
20                                     &num_displays, sizeof(u32));
21  
22 -       /* If we fail to get the number of displays, or it returns 0, then
23 +       /* If we fail to get the number of displays, then
24          * assume old firmware that doesn't have the mailbox call, so just
25          * set one display
26          */
27 -       if (ret || num_displays == 0) {
28 +       if (ret) {
29                 num_displays = 1;
30 -               DRM_WARN("Unable to determine number of displays's. Assuming 1\n");
31 +               DRM_WARN("Unable to determine number of displays - assuming 1\n");
32                 ret = 0;
33         }
34  
35 @@ -1344,17 +1344,21 @@ static int vc4_fkms_bind(struct device *
36                                   display_num);
37         }
38  
39 -       /* Map the SMI interrupt reg */
40 -       crtc_list[0]->regs = vc4_ioremap_regs(pdev, 0);
41 -       if (IS_ERR(crtc_list[0]->regs))
42 -               DRM_ERROR("Oh dear, failed to map registers\n");
43 -
44 -       writel(0, crtc_list[0]->regs + SMICS);
45 -       ret = devm_request_irq(dev, platform_get_irq(pdev, 0),
46 -                              vc4_crtc_irq_handler, 0, "vc4 firmware kms",
47 -                              crtc_list);
48 -       if (ret)
49 -               DRM_ERROR("Oh dear, failed to register IRQ\n");
50 +       if (num_displays > 0) {
51 +               /* Map the SMI interrupt reg */
52 +               crtc_list[0]->regs = vc4_ioremap_regs(pdev, 0);
53 +               if (IS_ERR(crtc_list[0]->regs))
54 +                       DRM_ERROR("Oh dear, failed to map registers\n");
55 +
56 +               writel(0, crtc_list[0]->regs + SMICS);
57 +               ret = devm_request_irq(dev, platform_get_irq(pdev, 0),
58 +                                      vc4_crtc_irq_handler, 0,
59 +                                      "vc4 firmware kms", crtc_list);
60 +               if (ret)
61 +                       DRM_ERROR("Oh dear, failed to register IRQ\n");
62 +       } else {
63 +               DRM_WARN("No displays found. Consider forcing hotplug if HDMI is attached\n");
64 +       }
65  
66         platform_set_drvdata(pdev, crtc_list);
67