Re: [PATCH 2/2] scsi: ufs: Add HCI capabilities sysfs group

[Bart Van Assche <bvanassche@acm.org>]

On 7/31/24 5:20 AM, Avri Altman wrote:
> +static ssize_t capabilities_show(struct device *dev,
> +		struct device_attribute *attr, char *buf)
> +{
> +	struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "0x%x\n", hba->capabilities);
> +}

For every new sysfs entry that is added, documentation must be added
in Documentation/ABI/testing/sysfs-driver-ufs.

> +static ssize_t ext_capabilities_show(struct device *dev,
> +		struct device_attribute *attr, char *buf)
> +{
> +	int ret;
> +	u32 val;
> +	struct ufs_hba *hba = dev_get_drvdata(dev);
> +
> +	if (hba->ufs_version < ufshci_version(4, 0))
> +		return -EOPNOTSUPP;
> +
> +	ret = ufshcd_read_hci_reg(hba, &val, REG_EXT_CONTROLLER_CAPABILITIES);
> +	if (ret)
> +		return ret;
> +
> +	return sysfs_emit(buf, "0x%x\n", val);
> +}

Host controller register reads must be protected by ufshcd_rpm_get_sync(hba) /
ufshcd_rpm_put_sync(hba).

Thanks,

Bart.