Re: [PATCH] mmc: sdhci-msm: Add sysfs attribute for error state in SDHCI MSM driver

[Sachin Gupta <quic_sachgupt@xxxxxxxxxxx>]

On 10/24/2024 4:54 PM, Adrian Hunter wrote:
> On 22/10/24 17:16, Sachin Gupta wrote:
> > Introduce a new sysfs attribute err_state to the SDHCI MSM driver.
> > The attribute allows users to query the error state of the SDHCI host controller.
>
> We already have err_stats and err_state in debugfs.  That seems
> more appropriate.

Thanks Adrian for pointing this out. I will check and get back.

> > Signed-off-by: Sachin Gupta <quic_sachgupt@xxxxxxxxxxx>
> > Signed-off-by: Sarthak Garg <quic_sartgarg@xxxxxxxxxxx>
> > ---
> >   drivers/mmc/host/sdhci-msm.c | 40 ++++++++++++++++++++++++++++++++++++
> >   1 file changed, 40 insertions(+)
> >
> > diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> > index e113b99a3eab..a256e3569a92 100644
> > --- a/drivers/mmc/host/sdhci-msm.c
> > +++ b/drivers/mmc/host/sdhci-msm.c
> > @@ -290,6 +290,7 @@ struct sdhci_msm_host {
> >   	u32 dll_config;
> >   	u32 ddr_config;
> >   	bool vqmmc_enabled;
> > +	bool err_occurred;
> >   };
> >   
> >   static const struct sdhci_msm_offset *sdhci_priv_msm_offset(struct sdhci_host *host)
> > @@ -2255,6 +2256,8 @@ static void sdhci_msm_dump_vendor_regs(struct sdhci_host *host)
> >   	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
> >   	const struct sdhci_msm_offset *msm_offset = msm_host->offset;
> >   
> > +	msm_host->err_occurred = true;
> > +
> >   	SDHCI_MSM_DUMP("----------- VENDOR REGISTER DUMP -----------\n");
> >   
> >   	SDHCI_MSM_DUMP(
> > @@ -2398,6 +2401,41 @@ static int sdhci_msm_gcc_reset(struct device *dev, struct sdhci_host *host)
> >   	return ret;
> >   }
> >   
> > +static ssize_t err_state_show(struct device *dev,
> > +			struct device_attribute *attr, char *buf)
> > +{
> > +	struct sdhci_host *host = dev_get_drvdata(dev);
> > +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> > +	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
> > +
> > +	if (!host || !host->mmc)
> > +		return -EINVAL;
> > +
> > +	return scnprintf(buf, PAGE_SIZE, "%d\n", !!msm_host->err_occurred);
> > +}
> > +
> > +static DEVICE_ATTR_RO(err_state);
> > +
> > +static struct attribute *sdhci_msm_sysfs_attrs[] = {
> > +	&dev_attr_err_state.attr,
> > +	NULL
> > +};
> > +
> > +static const struct attribute_group sdhci_msm_sysfs_group = {
> > +	.name = "qcom",
> > +	.attrs = sdhci_msm_sysfs_attrs,
> > +};
> > +
> > +static void sdhci_msm_init_sysfs(struct device *dev)
> > +{
> > +	int ret;
> > +
> > +	ret = sysfs_create_group(&dev->kobj, &sdhci_msm_sysfs_group);
> > +	if (ret)
> > +		dev_err(dev, "%s: Failed to create qcom sysfs group (err = %d)\n",
> > +				__func__, ret);
> > +}
> > +
> >   static int sdhci_msm_probe(struct platform_device *pdev)
> >   {
> >   	struct sdhci_host *host;
> > @@ -2442,6 +2480,8 @@ static int sdhci_msm_probe(struct platform_device *pdev)
> >   	sdhci_get_of_property(pdev);
> >   	sdhci_msm_get_of_property(pdev, host);
> >   
> > +	sdhci_msm_init_sysfs(&pdev->dev);
> > +
> >   	msm_host->saved_tuning_phase = INVALID_TUNING_PHASE;
> >   
> >   	ret = sdhci_msm_gcc_reset(&pdev->dev, host);