Messages in this thread | | | Subject | Re: [PATCH 1/7] media: hantro: add support for reset lines | From | Andrzej Pietrasiewicz <> | Date | Tue, 30 Nov 2021 11:39:22 +0100 |
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Hi Ezequiel,
W dniu 23.11.2021 o 19:07, Ezequiel Garcia pisze: > Hi all, > > Reset logic tends to be highly integration-specific, so it could be more robust > to deal with this in the machine specific file. I have some vague recollection > of our experience here when we integrated vc8000 last year, but I cannot recall > the outcome. >
Do you mean vpu->variant->init()?
That is the very first thing we do after the devm_*() calls. So any subsequent initialization that fails would want vpu->variant->deinit(). Maybe at this moment handling the resets at the common level is simpler? Existing drivers will get NULL anyway from devm_reset_control_array_get().
Regards,
Andrzej
> I'm Ccing Bob who might remember better. > > Thanks, > Ezequiel > > > > El mar., nov. 23, 2021 1:46 PM, Jernej Škrabec <jernej.skrabec@gmail.com > <mailto:jernej.skrabec@gmail.com>> escribió: > > 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: > > > On Tue, Nov 23, 2021 at 12:09:03PM +0100, Andrzej Pietrasiewicz wrote: > > >>> diff --git a/drivers/staging/media/hantro/hantro_drv.c b/drivers/staging/ > media/hantro/hantro_drv.c > > >>> 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) > > >>> return PTR_ERR(vpu->clocks[0].clk); > > >>> } > > >>> + vpu->resets = devm_reset_control_array_get(&pdev->dev, false, > true); > > >>> + 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); > > >>> @@ -978,10 +982,16 @@ static int hantro_probe(struct platform_device > *pdev) > > >>> 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 > > > > > >>> + 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 > > > > > > > > >>> + } > > >>> + > > >>> 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 > > > > > > > >>> + 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... > > >> > > >>> } > > >>> ret = v4l2_device_register(&pdev->dev, &vpu->v4l2_dev); > > >>> @@ -1037,6 +1047,8 @@ static int hantro_probe(struct platform_device > *pdev) > > >>> 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... > > >> > > >>> 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 > > > > > > > > >
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