Re: [PATCH 2/4] drm/panfrost: Drop redundant optional clock checks in runtime PM

From: Steven Price

Date: Fri Mar 20 2026 - 08:16:57 EST


On 04/03/2026 13:48, Biju wrote:
> From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
>
> The clk_enable() and clk_disable() APIs already handle NULL clock pointers
> gracefully — clk_enable() returns 0 and clk_disable() returns immediately
> when passed a NULL or optional clock. The explicit if (pfdev->bus_clock)
> guards around these calls in the runtime suspend/resume paths are
> therefore unnecessary. Remove them to simplify the code.
>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>

Reviewed-by: Steven Price <steven.price@xxxxxxx>

> ---
> drivers/gpu/drm/panfrost/panfrost_device.c | 12 ++++--------
> 1 file changed, 4 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/panfrost/panfrost_device.c b/drivers/gpu/drm/panfrost/panfrost_device.c
> index dedc13e56631..01e702a0b2f0 100644
> --- a/drivers/gpu/drm/panfrost/panfrost_device.c
> +++ b/drivers/gpu/drm/panfrost/panfrost_device.c
> @@ -429,11 +429,9 @@ static int panfrost_device_runtime_resume(struct device *dev)
> if (ret)
> goto err_clk;
>
> - if (pfdev->bus_clock) {
> - ret = clk_enable(pfdev->bus_clock);
> - if (ret)
> - goto err_bus_clk;
> - }
> + ret = clk_enable(pfdev->bus_clock);
> + if (ret)
> + goto err_bus_clk;
> }
>
> panfrost_device_reset(pfdev, true);
> @@ -464,9 +462,7 @@ static int panfrost_device_runtime_suspend(struct device *dev)
> panfrost_gpu_power_off(pfdev);
>
> if (pfdev->comp->pm_features & BIT(GPU_PM_RT)) {
> - if (pfdev->bus_clock)
> - clk_disable(pfdev->bus_clock);
> -
> + clk_disable(pfdev->bus_clock);
> clk_disable(pfdev->clock);
> reset_control_assert(pfdev->rstc);
> }