Re: [PATCH v3 1/3] ALSA: hda/tegra: Fix Tegra194 HDA reset failure

From: Sameer Pujar
Date: Wed Dec 22 2021 - 23:34:49 EST




On 12/23/2021 12:10 AM, Dmitry Osipenko wrote:
22.12.2021 07:35, Sameer Pujar пишет:
HDA regression is recently reported on Tegra194 based platforms.
This happens because "hda2codec_2x" reset does not really exist
in Tegra194 and it causes probe failure. All the HDA based audio
tests fail at the moment. This underlying issue is exposed by
commit c045ceb5a145 ("reset: tegra-bpmp: Handle errors in BPMP
response") which now checks return code of BPMP command response.
Fix this issue by skipping unavailable reset on Tegra194.

Signed-off-by: Sameer Pujar <spujar@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Depends-on: 87f0e46e7559 ("ALSA: hda/tegra: Reset hardware")
Is "Depends-on" a valid tag? I can't find it in Documentation/.

I do find the usage of the tag in many commits though there is no reference of this in doc. I always thought it would act as a reference when commits get pulled to other branches. If this is not true and it does not mean anything, I will drop this.


---
sound/pci/hda/hda_tegra.c | 45 ++++++++++++++++++++++++++++++++++++---------
1 file changed, 36 insertions(+), 9 deletions(-)

diff --git a/sound/pci/hda/hda_tegra.c b/sound/pci/hda/hda_tegra.c
index ea700395..7c3df54 100644
--- a/sound/pci/hda/hda_tegra.c
+++ b/sound/pci/hda/hda_tegra.c
@@ -68,14 +68,20 @@
*/
#define TEGRA194_NUM_SDO_LINES 4

+struct hda_tegra_soc {
+ bool has_hda2codec_2x_reset;
+};
+
struct hda_tegra {
struct azx chip;
struct device *dev;
- struct reset_control *reset;
+ struct reset_control_bulk_data resets[3];
struct clk_bulk_data clocks[3];
+ unsigned int nresets;
unsigned int nclocks;
void __iomem *regs;
struct work_struct probe_work;
+ const struct hda_tegra_soc *data;
};

#ifdef CONFIG_PM
@@ -170,7 +176,7 @@ static int __maybe_unused hda_tegra_runtime_resume(struct device *dev)
int rc;

if (!chip->running) {
- rc = reset_control_assert(hda->reset);
+ rc = reset_control_bulk_assert(hda->nresets, hda->resets);
if (rc)
return rc;
}
@@ -187,7 +193,7 @@ static int __maybe_unused hda_tegra_runtime_resume(struct device *dev)
} else {
usleep_range(10, 100);

- rc = reset_control_deassert(hda->reset);
+ rc = reset_control_bulk_deassert(hda->nresets, hda->resets);
if (rc)
return rc;
}
@@ -427,9 +433,17 @@ static int hda_tegra_create(struct snd_card *card,
return 0;
}

+static const struct hda_tegra_soc tegra30_data = {
+ .has_hda2codec_2x_reset = true,
+};
+
+static const struct hda_tegra_soc tegra194_data = {
+ .has_hda2codec_2x_reset = false,
+};
+
static const struct of_device_id hda_tegra_match[] = {
- { .compatible = "nvidia,tegra30-hda" },
- { .compatible = "nvidia,tegra194-hda" },
+ { .compatible = "nvidia,tegra30-hda", .data = &tegra30_data },
+ { .compatible = "nvidia,tegra194-hda", .data = &tegra194_data },
{},
};
MODULE_DEVICE_TABLE(of, hda_tegra_match);
@@ -449,6 +463,10 @@ static int hda_tegra_probe(struct platform_device *pdev)
hda->dev = &pdev->dev;
chip = &hda->chip;

+ hda->data = of_device_get_match_data(&pdev->dev);
+ if (!hda->data)
+ return -EINVAL;
hda->data can't ever be NULL because all hda_tegra_match[] compatibles
above have .data assigned. Technically this check is redundant.

Will remove.


Thierry suggested previously to name it "hda->soc", like we usually do
it in other drivers.

Previously I renamed strcture, but didn't update the member name. Will update.

err = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
THIS_MODULE, 0, &card);
if (err < 0) {
@@ -456,11 +474,20 @@ static int hda_tegra_probe(struct platform_device *pdev)
return err;
}

- hda->reset = devm_reset_control_array_get_exclusive(&pdev->dev);
- if (IS_ERR(hda->reset)) {
- err = PTR_ERR(hda->reset);
+ hda->resets[hda->nresets++].id = "hda";
+ hda->resets[hda->nresets++].id = "hda2hdmi";
+ /*
+ * "hda2codec_2x" reset is not present on Tegra194. Though DT would
+ * be updated to reflect this, but to have backward compatibility
+ * below is necessary.
+ */
+ if (hda->data->has_hda2codec_2x_reset)
+ hda->resets[hda->nresets++].id = "hda2codec_2x";
+
+ err = devm_reset_control_bulk_get_exclusive(&pdev->dev, hda->nresets,
+ hda->resets);
+ if (err)
goto out_free;
- }

hda->clocks[hda->nclocks++].id = "hda";
hda->clocks[hda->nclocks++].id = "hda2hdmi";

Not sure whether the above nits worth making v4. I'll leave it up to you
and other reviewers to decide.

Overall this patch looks good to me, thank you.

Reviewed-by: Dmitry Osipenko <digetx@xxxxxxxxx>