malidp_runtime_pm_resume() calls clk_prepare_enable() three times
without checking the return value. If any clock fails to enable, the
driver silently proceeds with unclocked hardware, leading to undefined
behavior.

Use clk_bulk_prepare_enable() which atomically enables all clocks and
automatically rolls back successfully enabled clocks on failure. This
is consistent with how the suspend path already uses
clk_bulk_disable_unprepare() in malidp_runtime_pm_suspend().

This issue was found by code review without access to Mali DP hardware.

Signed-off-by: Gustavo Kenji Mendonça Kaneko <[email protected]>
---
 drivers/gpu/drm/arm/malidp_drv.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/arm/malidp_drv.c b/drivers/gpu/drm/arm/malidp_drv.c
index b765f6c9eea4..1e4336c3a2fa 100644
--- a/drivers/gpu/drm/arm/malidp_drv.c
+++ b/drivers/gpu/drm/arm/malidp_drv.c
@@ -689,10 +689,17 @@ static int malidp_runtime_pm_resume(struct device *dev)
        struct drm_device *drm = dev_get_drvdata(dev);
        struct malidp_drm *malidp = drm_to_malidp(drm);
        struct malidp_hw_device *hwdev = malidp->dev;
+       struct clk_bulk_data clks[] = {
+               { .clk = hwdev->pclk },
+               { .clk = hwdev->aclk },
+               { .clk = hwdev->mclk },
+       };
+       int err;
+
+       err = clk_bulk_prepare_enable(ARRAY_SIZE(clks), clks);
+       if (err)
+               return err;
 
-       clk_prepare_enable(hwdev->pclk);
-       clk_prepare_enable(hwdev->aclk);
-       clk_prepare_enable(hwdev->mclk);
        hwdev->pm_suspended = false;
        malidp_de_irq_hw_init(hwdev);
        malidp_se_irq_hw_init(hwdev);
-- 
2.54.0


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