Re: [PATCH 08/18] ASoC: SOF: Intel: hda-mlink: introduce helpers for 'extended links' PM

On Mon, 27 Mar 2023 13:29:21 +0200, Peter Ujfalusi wrote:

+/*

• • Hardware recommendations are to wait ~10us before checking any hardware transition
• • reported by bits changing status.
• • This value does not need to be super-precise, a slack of 5us is perfectly acceptable.
• • The worst-case is about 1ms before reporting an issue
• */

+#define HDAML_POLL_DELAY_MIN_US 10 +#define HDAML_POLL_DELAY_SLACK_US 5 +#define HDAML_POLL_DELAY_RETRY 100

+static int check_power_active(u32 __iomem *lctl, int sublink, bool enable) +{

• int mask = BIT(sublink) << AZX_ML_LCTL_CPA_SHIFT;
• int retry = HDAML_POLL_DELAY_RETRY;
• u32 val;
• usleep_range(HDAML_POLL_DELAY_MIN_US,

•      HDAML_POLL_DELAY_MIN_US + HDAML_POLL_DELAY_SLACK_US);
  

• do {

• val = readl(lctl);
  

• if (enable) {
  

• 	if (val & mask)
  

• 		return 0;
  

• } else {
  

• 	if (!(val & mask))
  

• 		return 0;
  

• }
  

• usleep_range(HDAML_POLL_DELAY_MIN_US,
  

• 	     HDAML_POLL_DELAY_MIN_US + HDAML_POLL_DELAY_SLACK_US);
  

• } while (--retry);
• return -EIO;

+}

Can read_poll_timeout() and co be alternative?

thanks,

Takashi