RE: [PATCH v4 2/7] scsi: ufs-qcom: Add reset control support for host controller

From: Avri Altman
Date: Thu Nov 14 2019 - 04:03:17 EST


Hi,

>
>
> Add reset control for host controller so that host controller can be reset as
> required in its power up sequence.
>
> Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
> + ret = reset_control_assert(host->core_reset);
> + if (ret) {
> + dev_err(hba->dev, "%s: core_reset assert failed, err = %d\n",
> + __func__, ret);
> + goto out;
> + }
> +
> + /*
> + * The hardware requirement for delay between assert/deassert
> + * is at least 3-4 sleep clock (32.7KHz) cycles, which comes to
> + * ~125us (4/32768). To be on the safe side add 200us delay.
> + */
> + usleep_range(200, 210);
Aren't you sleeping anyway in your reset_control_ops?

> +
> + ret = reset_control_deassert(host->core_reset);
> + if (ret)
> + dev_err(hba->dev, "%s: core_reset deassert failed, err = %d\n",
> + __func__, ret);
> +
> + usleep_range(1000, 1100);
ditto