linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Dmitry Osipenko <digetx@gmail.com>
To: Thierry Reding <thierry.reding@gmail.com>,
	Jonathan Hunter <jonathanh@nvidia.com>,
	Peter Chen <Peter.Chen@nxp.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Alan Stern <stern@rowland.harvard.edu>,
	Felipe Balbi <balbi@kernel.org>,
	Matt Merhar <mattmerhar@protonmail.com>,
	Nicolas Chauvet <kwizart@gmail.com>,
	Peter Geis <pgwipeout@gmail.com>, Ion Agorria <ion@agorria.com>
Cc: linux-tegra@vger.kernel.org, linux-usb@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH v3 1/9] usb: phy: tegra: Add delay after power up
Date: Fri, 18 Dec 2020 15:02:38 +0300	[thread overview]
Message-ID: <20201218120246.7759-2-digetx@gmail.com> (raw)
In-Reply-To: <20201218120246.7759-1-digetx@gmail.com>

The PHY hardware needs the delay of 2ms after power up, otherwise initial
interrupt may be lost if USB controller is accessed before PHY is settled
down. Previously this issue was masked by implicit delays, but now it pops
up after squashing the older ehci-tegra driver into the ChipIdea driver.

Tested-by: Matt Merhar <mattmerhar@protonmail.com>
Tested-by: Nicolas Chauvet <kwizart@gmail.com>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Ion Agorria <ion@agorria.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 drivers/usb/phy/phy-tegra-usb.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/phy/phy-tegra-usb.c b/drivers/usb/phy/phy-tegra-usb.c
index 03a333797382..1296524e1bee 100644
--- a/drivers/usb/phy/phy-tegra-usb.c
+++ b/drivers/usb/phy/phy-tegra-usb.c
@@ -784,6 +784,9 @@ static int tegra_usb_phy_power_on(struct tegra_usb_phy *phy)
 
 	phy->powered_on = true;
 
+	/* Let PHY settle down */
+	usleep_range(2000, 2500);
+
 	return 0;
 }
 
-- 
2.29.2


  reply	other threads:[~2020-12-18 12:12 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-18 12:02 [PATCH v3 0/9] Support Runtime PM and host mode by Tegra ChipIdea USB driver Dmitry Osipenko
2020-12-18 12:02 ` Dmitry Osipenko [this message]
2020-12-18 12:02 ` [PATCH v3 2/9] usb: phy: tegra: Support waking up from a low power mode Dmitry Osipenko
2020-12-18 12:02 ` [PATCH v3 3/9] usb: chipidea: tegra: Remove MODULE_ALIAS Dmitry Osipenko
2020-12-18 12:02 ` [PATCH v3 4/9] usb: chipidea: tegra: Rename UDC to USB Dmitry Osipenko
2020-12-18 12:02 ` [PATCH v3 5/9] usb: chipidea: tegra: Support host mode Dmitry Osipenko
2020-12-18 12:02 ` [PATCH v3 6/9] usb: chipidea: tegra: Support runtime PM Dmitry Osipenko
2020-12-18 12:02 ` [PATCH v3 7/9] usb: chipidea: tegra: Specify TX FIFO threshold in UDC SoC info Dmitry Osipenko
2020-12-18 12:02 ` [PATCH v3 8/9] usb: host: ehci-tegra: Remove the driver Dmitry Osipenko
2020-12-18 12:02 ` [PATCH v3 9/9] ARM: tegra_defconfig: Enable USB_CHIPIDEA_HOST and remove USB_EHCI_TEGRA Dmitry Osipenko
2020-12-29  5:16 ` [PATCH v3 0/9] Support Runtime PM and host mode by Tegra ChipIdea USB driver Peter Chen
2020-12-29 14:26   ` Dmitry Osipenko
2021-01-12  6:56     ` Dmitry Osipenko
2021-01-13  1:20       ` Peter Chen
2021-01-13  9:01         ` Dmitry Osipenko
2021-01-13 10:27           ` Greg Kroah-Hartman
2021-01-13 14:28             ` Dmitry Osipenko

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20201218120246.7759-2-digetx@gmail.com \
    --to=digetx@gmail.com \
    --cc=Peter.Chen@nxp.com \
    --cc=balbi@kernel.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=ion@agorria.com \
    --cc=jonathanh@nvidia.com \
    --cc=kwizart@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-tegra@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=mattmerhar@protonmail.com \
    --cc=pgwipeout@gmail.com \
    --cc=stern@rowland.harvard.edu \
    --cc=thierry.reding@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).