Hi all,

Dne torek, 23. november 2021 ob 17:36:57 CET je Andrzej Pietrasiewicz 
napisal(a):

Hi Dan, hi Jernej,

W dniu 23.11.2021 o 15:59, Dan Carpenter pisze:

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On Tue, Nov 23, 2021 at 12:09:03PM +0100, Andrzej Pietrasiewicz wrote:

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diff --git a/drivers/staging/media/hantro/hantro_drv.c b/drivers/staging/

media/hantro/hantro_drv.c

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index ab2467998d29..8c3de31f51b3 100644

--- a/drivers/staging/media/hantro/hantro_drv.c
+++ b/drivers/staging/media/hantro/hantro_drv.c

@@ -905,6 +905,10 @@ static int hantro_probe(struct platform_device 

*pdev)

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   			return PTR_ERR(vpu->clocks[0].clk);
   	}
+	vpu->resets = devm_reset_control_array_get(&pdev->dev, false, 

true);

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+	if (IS_ERR(vpu->resets))
+		return PTR_ERR(vpu->resets);
+
   	num_bases = vpu->variant->num_regs ?: 1;
   	vpu->reg_bases = devm_kcalloc(&pdev->dev, num_bases,
   				      sizeof(*vpu->reg_bases), 

GFP_KERNEL);

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@@ -978,10 +982,16 @@ static int hantro_probe(struct platform_device 

*pdev)

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   	pm_runtime_use_autosuspend(vpu->dev);
   	pm_runtime_enable(vpu->dev);

         ^^^^^^^^^^^^^^^^^^^^^^^^^^^
It looks like this is the pm stuff that we have to unwind on error

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+	ret = reset_control_deassert(vpu->resets);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to deassert resets\n");
+		return ret;

                 ^^^^^^^^^^
So this return should be a goto undo_pm_stuff

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+	}
+
   	ret = clk_bulk_prepare(vpu->variant->num_clocks, vpu->clocks);
   	if (ret) {
   		dev_err(&pdev->dev, "Failed to prepare clocks\n");
-		return ret;

And this return should also have been a goto so it's a bug in the
original code.

So we probably want a separate patch addressing that first, and then
the series proper on top of that.

I was just about to suggest that.

Other drivers usually enable PM last, so they don't have PM calls in unwind 
code. However, I think current approach is just as valid (with a fix).

Best regards,
Jernej

Regards,

Andrzej

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+		goto err_rst_assert;

Before your patch is applied if clk_bulk_prepare() fails, we
simply return on the spot. After the patch is applied not only
do you...

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   	}
   	ret = v4l2_device_register(&pdev->dev, &vpu->v4l2_dev);

@@ -1037,6 +1047,8 @@ static int hantro_probe(struct platform_device 

*pdev)

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   	v4l2_device_unregister(&vpu->v4l2_dev);
   err_clk_unprepare:
   	clk_bulk_unprepare(vpu->variant->num_clocks, vpu->clocks);
+err_rst_assert:
+	reset_control_assert(vpu->resets);

...revert the effect of reset_control_deassert(), you also...

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   	pm_runtime_dont_use_autosuspend(vpu->dev);
   	pm_runtime_disable(vpu->dev);

... do pm_*() stuff. Is there any reason why this is needed?

So, yes, it's needed, but you're correct to spot that it's not
consistent.

regards,
dan carpenter