linux-usb.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Thierry Reding <thierry.reding@gmail.com>
To: Mathias Nyman <mathias.nyman@intel.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jon Hunter <jonathanh@nvidia.com>, JC Kuo <jckuo@nvidia.com>,
	Nagarjuna Kristam <nkristam@nvidia.com>,
	Sowjanya Komatineni <skomatineni@nvidia.com>,
	linux-usb@vger.kernel.org, linux-tegra@vger.kernel.org
Subject: [PATCH 10/10] usb: host: xhci-tegra: Implement basic ELPG support
Date: Mon, 25 Nov 2019 13:32:10 +0100	[thread overview]
Message-ID: <20191125123210.1564323-11-thierry.reding@gmail.com> (raw)
In-Reply-To: <20191125123210.1564323-1-thierry.reding@gmail.com>

From: Thierry Reding <treding@nvidia.com>

This implements basic engine-level powergate support which allows the
XUSB controller to be put into a low power mode on system sleep and get
it out of that low power mode again on resume.

Based on work by JC Kuo <jckuo@nvidia.com>.

Signed-off-by: Thierry Reding <treding@nvidia.com>
---
 drivers/usb/host/xhci-tegra.c | 137 ++++++++++++++++++++++++++++++++--
 1 file changed, 129 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index cd3afec408ea..d0e30927a73f 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -1451,6 +1451,45 @@ static int tegra_xusb_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM_SLEEP
+static bool xhci_hub_ports_suspended(struct xhci_hub *hub)
+{
+	struct device *dev = hub->hcd->self.controller;
+	bool status = true;
+	unsigned int i;
+	u32 value;
+
+	for (i = 0; i < hub->num_ports; i++) {
+		value = readl(hub->ports[i]->addr);
+		if ((value & PORT_PE) == 0)
+			continue;
+
+		if ((value & PORT_PLS_MASK) != XDEV_U3) {
+			dev_info(dev, "%u-%u isn't suspended: %#010x\n",
+				 hub->hcd->self.busnum, i + 1, value);
+			status = false;
+		}
+	}
+
+	return status;
+}
+
+static int tegra_xusb_check_ports(struct tegra_xusb *tegra)
+{
+	struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd);
+	unsigned long flags;
+	int err = 0;
+
+	spin_lock_irqsave(&xhci->lock, flags);
+
+	if (!xhci_hub_ports_suspended(&xhci->usb2_rhub) ||
+	    !xhci_hub_ports_suspended(&xhci->usb3_rhub))
+		err = -EBUSY;
+
+	spin_unlock_irqrestore(&xhci->lock, flags);
+
+	return err;
+}
+
 static void tegra_xusb_save_context(struct tegra_xusb *tegra)
 {
 	const struct tegra_xusb_context_soc *soc = tegra->soc->context;
@@ -1485,31 +1524,113 @@ static void tegra_xusb_restore_context(struct tegra_xusb *tegra)
 	}
 }
 
-static int tegra_xusb_suspend(struct device *dev)
+static int tegra_xusb_enter_elpg(struct tegra_xusb *tegra, bool wakeup)
 {
-	struct tegra_xusb *tegra = dev_get_drvdata(dev);
 	struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd);
-	bool wakeup = device_may_wakeup(dev);
+	u32 value;
 	int err;
 
-	/* TODO: Powergate controller across suspend/resume. */
+	err = tegra_xusb_check_ports(tegra);
+	if (err < 0) {
+		dev_err(tegra->dev, "not all ports suspended: %d\n", err);
+		return err;
+	}
+
 	err = xhci_suspend(xhci, wakeup);
-	if (err < 0)
+	if (err < 0) {
+		dev_err(tegra->dev, "failed to suspend XHCI: %d\n", err);
 		return err;
+	}
 
 	tegra_xusb_save_context(tegra);
+	tegra_xusb_phy_disable(tegra);
+	tegra_xusb_clk_disable(tegra);
 
 	return 0;
 }
 
-static int tegra_xusb_resume(struct device *dev)
+static int tegra_xusb_exit_elpg(struct tegra_xusb *tegra, bool wakeup)
 {
-	struct tegra_xusb *tegra = dev_get_drvdata(dev);
 	struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd);
+	u32 value;
+	int err;
 
+	err = tegra_xusb_clk_enable(tegra);
+	if (err < 0) {
+		dev_err(tegra->dev, "failed to enable clocks: %d\n", err);
+		return err;
+	}
+
+	err = tegra_xusb_phy_enable(tegra);
+	if (err < 0) {
+		dev_err(tegra->dev, "failed to enable PHYs: %d\n", err);
+		goto disable_clk;
+	}
+
+	tegra_xusb_config(tegra);
 	tegra_xusb_restore_context(tegra);
 
-	return xhci_resume(xhci, false);
+	err = tegra_xusb_load_firmware(tegra);
+	if (err < 0) {
+		dev_err(tegra->dev, "failed to load firmware: %d\n", err);
+		goto disable_phy;
+	}
+
+	err = __tegra_xusb_enable_firmware_messages(tegra);
+	if (err < 0) {
+		dev_err(tegra->dev, "failed to enable messages: %d\n", err);
+		goto disable_phy;
+	}
+
+	err = xhci_resume(xhci, true);
+	if (err < 0) {
+		dev_err(tegra->dev, "failed to resume XHCI: %d\n", err);
+		goto disable_phy;
+	}
+
+	return 0;
+
+disable_phy:
+	tegra_xusb_phy_disable(tegra);
+disable_clk:
+	tegra_xusb_clk_disable(tegra);
+	return err;
+}
+
+static int tegra_xusb_suspend(struct device *dev)
+{
+	struct tegra_xusb *tegra = dev_get_drvdata(dev);
+	bool wakeup = device_may_wakeup(dev);
+	int err;
+
+	synchronize_irq(tegra->mbox_irq);
+
+	mutex_lock(&tegra->lock);
+
+	err = tegra_xusb_enter_elpg(tegra, wakeup);
+	if (err < 0)
+		goto unlock;
+
+unlock:
+	mutex_unlock(&tegra->lock);
+	return err;
+}
+
+static int tegra_xusb_resume(struct device *dev)
+{
+	struct tegra_xusb *tegra = dev_get_drvdata(dev);
+	bool wakeup = device_may_wakeup(dev);
+	int err;
+
+	mutex_lock(&tegra->lock);
+
+	err = tegra_xusb_exit_elpg(tegra, wakeup);
+	if (err < 0)
+		goto unlock;
+
+unlock:
+	mutex_unlock(&tegra->lock);
+	return err;
 }
 #endif
 
-- 
2.23.0


  parent reply	other threads:[~2019-11-25 12:32 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-25 12:32 [PATCH 00/10] usb: host: xhci-tegra: Implement basic ELPG support Thierry Reding
2019-11-25 12:32 ` [PATCH 01/10] usb: host: xhci-tegra: Fix "tega" -> "tegra" typo Thierry Reding
2019-11-26  2:50   ` JC Kuo
2019-11-25 12:32 ` [PATCH 02/10] usb: host: xhci-tegra: Separate firmware request and load Thierry Reding
2019-11-25 12:32 ` [PATCH 03/10] usb: host: xhci-tegra: Avoid a fixed duration sleep Thierry Reding
2019-11-25 13:33   ` Mikko Perttunen
2019-11-25 12:32 ` [PATCH 04/10] usb: host: xhci-tegra: Use CNR as firmware ready indicator Thierry Reding
2019-11-25 12:32 ` [PATCH 05/10] usb: host: xhci-tegra: Extract firmware enable helper Thierry Reding
2019-11-25 12:32 ` [PATCH 06/10] usb: host: xhci-tegra: Reuse stored register base address Thierry Reding
2019-11-25 12:32 ` [PATCH 07/10] usb: host: xhci-tegra: Enable runtime PM as late as possible Thierry Reding
2019-11-25 12:32 ` [PATCH 08/10] usb: host: xhci-tegra: Add support for XUSB context save/restore Thierry Reding
2019-11-25 12:32 ` [PATCH 09/10] usb: host: xhci-tegra: Add XUSB controller context Thierry Reding
2019-11-25 12:32 ` Thierry Reding [this message]
2019-11-26 15:43   ` [PATCH 10/10] usb: host: xhci-tegra: Implement basic ELPG support Mathias Nyman
2019-12-06 14:27     ` Thierry Reding

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=20191125123210.1564323-11-thierry.reding@gmail.com \
    --to=thierry.reding@gmail.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=jckuo@nvidia.com \
    --cc=jonathanh@nvidia.com \
    --cc=linux-tegra@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=mathias.nyman@intel.com \
    --cc=nkristam@nvidia.com \
    --cc=skomatineni@nvidia.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).