Move DWC2 driver out of staging

The DWC2 driver should now be in good enough shape to move out of
staging. I have stress tested it overnight on RPI running mass
storage and Ethernet transfers in parallel, and for several days
on our proprietary PCI-based platform.

Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 492 insertions, 0 deletions

diff --git a/drivers/usb/dwc2/core_intr.c b/drivers/usb/dwc2/core_intr.c
new file mode 100644
index 000000000000..8205799e6db3
--- /dev/null
+++ b/drivers/usb/dwc2/core_intr.c
@@ -0,0 +1,492 @@
+/*
+ * core_intr.c - DesignWare HS OTG Controller common interrupt handling
+ *
+ * Copyright (C) 2004-2013 Synopsys, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The names of the above-listed copyright holders may not be used
+ *    to endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") as published by the Free Software
+ * Foundation; either version 2 of the License, or (at your option) any
+ * later version.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * This file contains the common interrupt handlers
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+
+#include <linux/usb/hcd.h>
+#include <linux/usb/ch11.h>
+
+#include "core.h"
+#include "hcd.h"
+
+static const char *dwc2_op_state_str(struct dwc2_hsotg *hsotg)
+{
+	switch (hsotg->op_state) {
+	case OTG_STATE_A_HOST:
+		return "a_host";
+	case OTG_STATE_A_SUSPEND:
+		return "a_suspend";
+	case OTG_STATE_A_PERIPHERAL:
+		return "a_peripheral";
+	case OTG_STATE_B_PERIPHERAL:
+		return "b_peripheral";
+	case OTG_STATE_B_HOST:
+		return "b_host";
+	default:
+		return "unknown";
+	}
+}
+
+/**
+ * dwc2_handle_mode_mismatch_intr() - Logs a mode mismatch warning message
+ *
+ * @hsotg: Programming view of DWC_otg controller
+ */
+static void dwc2_handle_mode_mismatch_intr(struct dwc2_hsotg *hsotg)
+{
+	dev_warn(hsotg->dev, "Mode Mismatch Interrupt: currently in %s mode\n",
+		 dwc2_is_host_mode(hsotg) ? "Host" : "Device");
+
+	/* Clear interrupt */
+	writel(GINTSTS_MODEMIS, hsotg->regs + GINTSTS);
+}
+
+/**
+ * dwc2_handle_otg_intr() - Handles the OTG Interrupts. It reads the OTG
+ * Interrupt Register (GOTGINT) to determine what interrupt has occurred.
+ *
+ * @hsotg: Programming view of DWC_otg controller
+ */
+static void dwc2_handle_otg_intr(struct dwc2_hsotg *hsotg)
+{
+	u32 gotgint;
+	u32 gotgctl;
+	u32 gintmsk;
+
+	gotgint = readl(hsotg->regs + GOTGINT);
+	gotgctl = readl(hsotg->regs + GOTGCTL);
+	dev_dbg(hsotg->dev, "++OTG Interrupt gotgint=%0x [%s]\n", gotgint,
+		dwc2_op_state_str(hsotg));
+
+	if (gotgint & GOTGINT_SES_END_DET) {
+		dev_dbg(hsotg->dev,
+			" ++OTG Interrupt: Session End Detected++ (%s)\n",
+			dwc2_op_state_str(hsotg));
+		gotgctl = readl(hsotg->regs + GOTGCTL);
+
+		if (hsotg->op_state == OTG_STATE_B_HOST) {
+			hsotg->op_state = OTG_STATE_B_PERIPHERAL;
+		} else {
+			/*
+			 * If not B_HOST and Device HNP still set, HNP did
+			 * not succeed!
+			 */
+			if (gotgctl & GOTGCTL_DEVHNPEN) {
+				dev_dbg(hsotg->dev, "Session End Detected\n");
+				dev_err(hsotg->dev,
+					"Device Not Connected/Responding!\n");
+			}
+
+			/*
+			 * If Session End Detected the B-Cable has been
+			 * disconnected
+			 */
+			/* Reset to a clean state */
+			hsotg->lx_state = DWC2_L0;
+		}
+
+		gotgctl = readl(hsotg->regs + GOTGCTL);
+		gotgctl &= ~GOTGCTL_DEVHNPEN;
+		writel(gotgctl, hsotg->regs + GOTGCTL);
+	}
+
+	if (gotgint & GOTGINT_SES_REQ_SUC_STS_CHNG) {
+		dev_dbg(hsotg->dev,
+			" ++OTG Interrupt: Session Request Success Status Change++\n");
+		gotgctl = readl(hsotg->regs + GOTGCTL);
+		if (gotgctl & GOTGCTL_SESREQSCS) {
+			if (hsotg->core_params->phy_type ==
+					DWC2_PHY_TYPE_PARAM_FS
+			    && hsotg->core_params->i2c_enable > 0) {
+				hsotg->srp_success = 1;
+			} else {
+				/* Clear Session Request */
+				gotgctl = readl(hsotg->regs + GOTGCTL);
+				gotgctl &= ~GOTGCTL_SESREQ;
+				writel(gotgctl, hsotg->regs + GOTGCTL);
+			}
+		}
+	}
+
+	if (gotgint & GOTGINT_HST_NEG_SUC_STS_CHNG) {
+		/*
+		 * Print statements during the HNP interrupt handling
+		 * can cause it to fail
+		 */
+		gotgctl = readl(hsotg->regs + GOTGCTL);
+		/*
+		 * WA for 3.00a- HW is not setting cur_mode, even sometimes
+		 * this does not help
+		 */
+		if (hsotg->hw_params.snpsid >= DWC2_CORE_REV_3_00a)
+			udelay(100);
+		if (gotgctl & GOTGCTL_HSTNEGSCS) {
+			if (dwc2_is_host_mode(hsotg)) {
+				hsotg->op_state = OTG_STATE_B_HOST;
+				/*
+				 * Need to disable SOF interrupt immediately.
+				 * When switching from device to host, the PCD
+				 * interrupt handler won't handle the interrupt
+				 * if host mode is already set. The HCD
+				 * interrupt handler won't get called if the
+				 * HCD state is HALT. This means that the
+				 * interrupt does not get handled and Linux
+				 * complains loudly.
+				 */
+				gintmsk = readl(hsotg->regs + GINTMSK);
+				gintmsk &= ~GINTSTS_SOF;
+				writel(gintmsk, hsotg->regs + GINTMSK);
+
+				/*
+				 * Call callback function with spin lock
+				 * released
+				 */
+				spin_unlock(&hsotg->lock);
+
+				/* Initialize the Core for Host mode */
+				dwc2_hcd_start(hsotg);
+				spin_lock(&hsotg->lock);
+				hsotg->op_state = OTG_STATE_B_HOST;
+			}
+		} else {
+			gotgctl = readl(hsotg->regs + GOTGCTL);
+			gotgctl &= ~(GOTGCTL_HNPREQ | GOTGCTL_DEVHNPEN);
+			writel(gotgctl, hsotg->regs + GOTGCTL);
+			dev_dbg(hsotg->dev, "HNP Failed\n");
+			dev_err(hsotg->dev,
+				"Device Not Connected/Responding\n");
+		}
+	}
+
+	if (gotgint & GOTGINT_HST_NEG_DET) {
+		/*
+		 * The disconnect interrupt is set at the same time as
+		 * Host Negotiation Detected. During the mode switch all
+		 * interrupts are cleared so the disconnect interrupt
+		 * handler will not get executed.
+		 */
+		dev_dbg(hsotg->dev,
+			" ++OTG Interrupt: Host Negotiation Detected++ (%s)\n",
+			(dwc2_is_host_mode(hsotg) ? "Host" : "Device"));
+		if (dwc2_is_device_mode(hsotg)) {
+			dev_dbg(hsotg->dev, "a_suspend->a_peripheral (%d)\n",
+				hsotg->op_state);
+			spin_unlock(&hsotg->lock);
+			dwc2_hcd_disconnect(hsotg);
+			spin_lock(&hsotg->lock);
+			hsotg->op_state = OTG_STATE_A_PERIPHERAL;
+		} else {
+			/* Need to disable SOF interrupt immediately */
+			gintmsk = readl(hsotg->regs + GINTMSK);
+			gintmsk &= ~GINTSTS_SOF;
+			writel(gintmsk, hsotg->regs + GINTMSK);
+			spin_unlock(&hsotg->lock);
+			dwc2_hcd_start(hsotg);
+			spin_lock(&hsotg->lock);
+			hsotg->op_state = OTG_STATE_A_HOST;
+		}
+	}
+
+	if (gotgint & GOTGINT_A_DEV_TOUT_CHG)
+		dev_dbg(hsotg->dev,
+			" ++OTG Interrupt: A-Device Timeout Change++\n");
+	if (gotgint & GOTGINT_DBNCE_DONE)
+		dev_dbg(hsotg->dev, " ++OTG Interrupt: Debounce Done++\n");
+
+	/* Clear GOTGINT */
+	writel(gotgint, hsotg->regs + GOTGINT);
+}
+
+/**
+ * dwc2_handle_conn_id_status_change_intr() - Handles the Connector ID Status
+ * Change Interrupt
+ *
+ * @hsotg: Programming view of DWC_otg controller
+ *
+ * Reads the OTG Interrupt Register (GOTCTL) to determine whether this is a
+ * Device to Host Mode transition or a Host to Device Mode transition. This only
+ * occurs when the cable is connected/removed from the PHY connector.
+ */
+static void dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg *hsotg)
+{
+	u32 gintmsk = readl(hsotg->regs + GINTMSK);
+
+	/* Need to disable SOF interrupt immediately */
+	gintmsk &= ~GINTSTS_SOF;
+	writel(gintmsk, hsotg->regs + GINTMSK);
+
+	dev_dbg(hsotg->dev, " ++Connector ID Status Change Interrupt++  (%s)\n",
+		dwc2_is_host_mode(hsotg) ? "Host" : "Device");
+
+	/*
+	 * Need to schedule a work, as there are possible DELAY function calls.
+	 * Release lock before scheduling workq as it holds spinlock during
+	 * scheduling.
+	 */
+	spin_unlock(&hsotg->lock);
+	queue_work(hsotg->wq_otg, &hsotg->wf_otg);
+	spin_lock(&hsotg->lock);
+
+	/* Clear interrupt */
+	writel(GINTSTS_CONIDSTSCHNG, hsotg->regs + GINTSTS);
+}
+
+/**
+ * dwc2_handle_session_req_intr() - This interrupt indicates that a device is
+ * initiating the Session Request Protocol to request the host to turn on bus
+ * power so a new session can begin
+ *
+ * @hsotg: Programming view of DWC_otg controller
+ *
+ * This handler responds by turning on bus power. If the DWC_otg controller is
+ * in low power mode, this handler brings the controller out of low power mode
+ * before turning on bus power.
+ */
+static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg)
+{
+	dev_dbg(hsotg->dev, "++Session Request Interrupt++\n");
+
+	/* Clear interrupt */
+	writel(GINTSTS_SESSREQINT, hsotg->regs + GINTSTS);
+}
+
+/*
+ * This interrupt indicates that the DWC_otg controller has detected a
+ * resume or remote wakeup sequence. If the DWC_otg controller is in
+ * low power mode, the handler must brings the controller out of low
+ * power mode. The controller automatically begins resume signaling.
+ * The handler schedules a time to stop resume signaling.
+ */
+static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg)
+{
+	dev_dbg(hsotg->dev, "++Resume or Remote Wakeup Detected Interrupt++\n");
+	dev_dbg(hsotg->dev, "%s lxstate = %d\n", __func__, hsotg->lx_state);
+
+	if (dwc2_is_device_mode(hsotg)) {
+		dev_dbg(hsotg->dev, "DSTS=0x%0x\n", readl(hsotg->regs + DSTS));
+		if (hsotg->lx_state == DWC2_L2) {
+			u32 dctl = readl(hsotg->regs + DCTL);
+
+			/* Clear Remote Wakeup Signaling */
+			dctl &= ~DCTL_RMTWKUPSIG;
+			writel(dctl, hsotg->regs + DCTL);
+		}
+		/* Change to L0 state */
+		hsotg->lx_state = DWC2_L0;
+	} else {
+		if (hsotg->lx_state != DWC2_L1) {
+			u32 pcgcctl = readl(hsotg->regs + PCGCTL);
+
+			/* Restart the Phy Clock */
+			pcgcctl &= ~PCGCTL_STOPPCLK;
+			writel(pcgcctl, hsotg->regs + PCGCTL);
+			mod_timer(&hsotg->wkp_timer,
+				  jiffies + msecs_to_jiffies(71));
+		} else {
+			/* Change to L0 state */
+			hsotg->lx_state = DWC2_L0;
+		}
+	}
+
+	/* Clear interrupt */
+	writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS);
+}
+
+/*
+ * This interrupt indicates that a device has been disconnected from the
+ * root port
+ */
+static void dwc2_handle_disconnect_intr(struct dwc2_hsotg *hsotg)
+{
+	dev_dbg(hsotg->dev, "++Disconnect Detected Interrupt++ (%s) %s\n",
+		dwc2_is_host_mode(hsotg) ? "Host" : "Device",
+		dwc2_op_state_str(hsotg));
+
+	/* Change to L3 (OFF) state */
+	hsotg->lx_state = DWC2_L3;
+
+	writel(GINTSTS_DISCONNINT, hsotg->regs + GINTSTS);
+}
+
+/*
+ * This interrupt indicates that SUSPEND state has been detected on the USB.
+ *
+ * For HNP the USB Suspend interrupt signals the change from "a_peripheral"
+ * to "a_host".
+ *
+ * When power management is enabled the core will be put in low power mode.
+ */
+static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg)
+{
+	u32 dsts;
+
+	dev_dbg(hsotg->dev, "USB SUSPEND\n");
+
+	if (dwc2_is_device_mode(hsotg)) {
+		/*
+		 * Check the Device status register to determine if the Suspend
+		 * state is active
+		 */
+		dsts = readl(hsotg->regs + DSTS);
+		dev_dbg(hsotg->dev, "DSTS=0x%0x\n", dsts);
+		dev_dbg(hsotg->dev,
+			"DSTS.Suspend Status=%d HWCFG4.Power Optimize=%d\n",
+			!!(dsts & DSTS_SUSPSTS),
+			hsotg->hw_params.power_optimized);
+	} else {
+		if (hsotg->op_state == OTG_STATE_A_PERIPHERAL) {
+			dev_dbg(hsotg->dev, "a_peripheral->a_host\n");
+
+			/* Clear the a_peripheral flag, back to a_host */
+			spin_unlock(&hsotg->lock);
+			dwc2_hcd_start(hsotg);
+			spin_lock(&hsotg->lock);
+			hsotg->op_state = OTG_STATE_A_HOST;
+		}
+	}
+
+	/* Change to L2 (suspend) state */
+	hsotg->lx_state = DWC2_L2;
+
+	/* Clear interrupt */
+	writel(GINTSTS_USBSUSP, hsotg->regs + GINTSTS);
+}
+
+#define GINTMSK_COMMON	(GINTSTS_WKUPINT | GINTSTS_SESSREQINT |		\
+			 GINTSTS_CONIDSTSCHNG | GINTSTS_OTGINT |	\
+			 GINTSTS_MODEMIS | GINTSTS_DISCONNINT |		\
+			 GINTSTS_USBSUSP | GINTSTS_PRTINT)
+
+/*
+ * This function returns the Core Interrupt register
+ */
+static u32 dwc2_read_common_intr(struct dwc2_hsotg *hsotg)
+{
+	u32 gintsts;
+	u32 gintmsk;
+	u32 gahbcfg;
+	u32 gintmsk_common = GINTMSK_COMMON;
+
+	gintsts = readl(hsotg->regs + GINTSTS);
+	gintmsk = readl(hsotg->regs + GINTMSK);
+	gahbcfg = readl(hsotg->regs + GAHBCFG);
+
+	/* If any common interrupts set */
+	if (gintsts & gintmsk_common)
+		dev_dbg(hsotg->dev, "gintsts=%08x  gintmsk=%08x\n",
+			gintsts, gintmsk);
+
+	if (gahbcfg & GAHBCFG_GLBL_INTR_EN)
+		return gintsts & gintmsk & gintmsk_common;
+	else
+		return 0;
+}
+
+/*
+ * Common interrupt handler
+ *
+ * The common interrupts are those that occur in both Host and Device mode.
+ * This handler handles the following interrupts:
+ * - Mode Mismatch Interrupt
+ * - OTG Interrupt
+ * - Connector ID Status Change Interrupt
+ * - Disconnect Interrupt
+ * - Session Request Interrupt
+ * - Resume / Remote Wakeup Detected Interrupt
+ * - Suspend Interrupt
+ */
+irqreturn_t dwc2_handle_common_intr(int irq, void *dev)
+{
+	struct dwc2_hsotg *hsotg = dev;
+	u32 gintsts;
+	irqreturn_t retval = IRQ_NONE;
+
+	if (!dwc2_is_controller_alive(hsotg)) {
+		dev_warn(hsotg->dev, "Controller is dead\n");
+		goto out;
+	}
+
+	spin_lock(&hsotg->lock);
+
+	gintsts = dwc2_read_common_intr(hsotg);
+	if (gintsts & ~GINTSTS_PRTINT)
+		retval = IRQ_HANDLED;
+
+	if (gintsts & GINTSTS_MODEMIS)
+		dwc2_handle_mode_mismatch_intr(hsotg);
+	if (gintsts & GINTSTS_OTGINT)
+		dwc2_handle_otg_intr(hsotg);
+	if (gintsts & GINTSTS_CONIDSTSCHNG)
+		dwc2_handle_conn_id_status_change_intr(hsotg);
+	if (gintsts & GINTSTS_DISCONNINT)
+		dwc2_handle_disconnect_intr(hsotg);
+	if (gintsts & GINTSTS_SESSREQINT)
+		dwc2_handle_session_req_intr(hsotg);
+	if (gintsts & GINTSTS_WKUPINT)
+		dwc2_handle_wakeup_detected_intr(hsotg);
+	if (gintsts & GINTSTS_USBSUSP)
+		dwc2_handle_usb_suspend_intr(hsotg);
+
+	if (gintsts & GINTSTS_PRTINT) {
+		/*
+		 * The port interrupt occurs while in device mode with HPRT0
+		 * Port Enable/Disable
+		 */
+		if (dwc2_is_device_mode(hsotg)) {
+			dev_dbg(hsotg->dev,
+				" --Port interrupt received in Device mode--\n");
+			gintsts = GINTSTS_PRTINT;
+			writel(gintsts, hsotg->regs + GINTSTS);
+			retval = 1;
+		}
+	}
+
+	spin_unlock(&hsotg->lock);
+out:
+	return retval;
+}
+EXPORT_SYMBOL_GPL(dwc2_handle_common_intr);