Re: [RFCv1 7/8] phy: amlogic: meson8b-usb2: Power off the PHY by putting it into reset mode.
From: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Date: 2021-06-17 22:37:17
Also in:
linux-amlogic, linux-phy, lkml
Hi Anand, On Thu, Jun 17, 2021 at 9:44 PM Anand Moon [off-list ref] wrote: [...]
quoted hunk ↗ jump to hunk
@@ -245,8 +250,6 @@ static int phy_meson8b_usb2_power_on(struct phy *phy) regmap_update_bits(priv->regmap, REG_CTRL, REG_CTRL_FSEL_MASK, 0x5 << REG_CTRL_FSEL_SHIFT); /* reset the PHY */ - regmap_update_bits(priv->regmap, REG_CTRL, REG_CTRL_POWER_ON_RESET, - REG_CTRL_POWER_ON_RESET);
The vendor driver uses the following sequence for the power on reset: - set the power on reset bit - wait 500us - clear the power on reset bit - wait 500us With your change we now: - wait 500us - clear the power on reset bit - wait 500us I don't know if this is sufficient to bring the PHY into a well-defined state. Maybe it works, maybe it doesn't reset at all in this case - I don't know how to verify this though. Best regards, Martin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel