Re: [PATCH v6 17/17] mmc: sdhci-cadence: Support mmc hardware reset
From: Philipp Zabel <p.zabel@pengutronix.de>
Date: 2022-08-22 07:04:39
Also in:
linux-devicetree, linux-mmc, lkml
Hi Brad, On Sa, 2022-08-20 at 12:57 -0700, Brad Larson wrote: [...]
+static void sdhci_mmc_hw_reset(struct mmc_host *mmc)
+{
+ struct sdhci_host *host = mmc_priv(mmc);
+ struct sdhci_cdns_priv *priv = sdhci_cdns_priv(host);
+
+ dev_info(mmc_dev(host->mmc), "emmc hardware reset\n");
+
+ reset_control_assert(priv->rst_hw);
+ /* For eMMC, minimum is 1us but give it 9us for good measure */
+ udelay(9);At a glance, this seems excessive. Is there a reason 9 us is better than, say, 2 or 3? [...]
quoted hunk ↗ jump to hunk
@@ -520,6 +538,17 @@ static int sdhci_cdns_probe(struct platform_device *pdev)if (ret) goto free; + if (host->mmc->caps & MMC_CAP_HW_RESET) { + priv->rst_hw = devm_reset_control_get_optional_exclusive(dev, "hw");
This should be described in cdns,sdhci.yaml first. regards Philipp _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel