Merge tag 'usb-for-v3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next

Felipe writes:

usb: patches for v3.17 merge window

Surprisingly enough, while a big set of patches, the majority is
composed of cleanups (using devm_*, fixing sparse errors, moving
code around, adding const, etc).

The highlights are addition of new support for PLX USB338x devices,
and support for USB 2.0-only configurations of the DWC3 IP core.

Signed-of-by: Felipe Balbi <balbi@ti.com>

1 files changed, 97 insertions, 7 deletions

diff --git a/drivers/usb/musb/musb_dsps.c b/drivers/usb/musb/musb_dsps.c
index 09529f9..c791ba5 100644
--- a/drivers/usb/musb/musb_dsps.c
+++ b/drivers/usb/musb/musb_dsps.c
@@ -56,16 +56,24 @@ static const struct of_device_id musb_dsps_of_match[];
  * dependent on musb core layer symbols.
  */
 static inline u8 dsps_readb(const void __iomem *addr, unsigned offset)
-	{ return __raw_readb(addr + offset); }
+{
+	return __raw_readb(addr + offset);
+}
 
 static inline u32 dsps_readl(const void __iomem *addr, unsigned offset)
-	{ return __raw_readl(addr + offset); }
+{
+	return __raw_readl(addr + offset);
+}
 
 static inline void dsps_writeb(void __iomem *addr, unsigned offset, u8 data)
-	{ __raw_writeb(data, addr + offset); }
+{
+	__raw_writeb(data, addr + offset);
+}
 
 static inline void dsps_writel(void __iomem *addr, unsigned offset, u32 data)
-	{ __raw_writel(data, addr + offset); }
+{
+	__raw_writel(data, addr + offset);
+}
 
 /**
  * DSPS musb wrapper register offset.
@@ -136,6 +144,7 @@ struct dsps_glue {
 	const struct dsps_musb_wrapper *wrp; /* wrapper register offsets */
 	struct timer_list timer;	/* otg_workaround timer */
 	unsigned long last_timer;    /* last timer data for each instance */
+	bool sw_babble_enabled;
 
 	struct dsps_context context;
 	struct debugfs_regset32 regset;
@@ -469,6 +478,19 @@ static int dsps_musb_init(struct musb *musb)
 	val &= ~(1 << wrp->otg_disable);
 	dsps_writel(musb->ctrl_base, wrp->phy_utmi, val);
 
+	/*
+	 *  Check whether the dsps version has babble control enabled.
+	 * In latest silicon revision the babble control logic is enabled.
+	 * If MUSB_BABBLE_CTL returns 0x4 then we have the babble control
+	 * logic enabled.
+	 */
+	val = dsps_readb(musb->mregs, MUSB_BABBLE_CTL);
+	if (val == MUSB_BABBLE_RCV_DISABLE) {
+		glue->sw_babble_enabled = true;
+		val |= MUSB_BABBLE_SW_SESSION_CTRL;
+		dsps_writeb(musb->mregs, MUSB_BABBLE_CTL, val);
+	}
+
 	ret = dsps_musb_dbg_init(musb, glue);
 	if (ret)
 		return ret;
@@ -535,14 +557,82 @@ static int dsps_musb_set_mode(struct musb *musb, u8 mode)
 	return 0;
 }
 
-static void dsps_musb_reset(struct musb *musb)
+static bool  sw_babble_control(struct musb *musb)
+{
+	u8 babble_ctl;
+	bool session_restart =  false;
+
+	babble_ctl = dsps_readb(musb->mregs, MUSB_BABBLE_CTL);
+	dev_dbg(musb->controller, "babble: MUSB_BABBLE_CTL value %x\n",
+		babble_ctl);
+	/*
+	 * check line monitor flag to check whether babble is
+	 * due to noise
+	 */
+	dev_dbg(musb->controller, "STUCK_J is %s\n",
+		babble_ctl & MUSB_BABBLE_STUCK_J ? "set" : "reset");
+
+	if (babble_ctl & MUSB_BABBLE_STUCK_J) {
+		int timeout = 10;
+
+		/*
+		 * babble is due to noise, then set transmit idle (d7 bit)
+		 * to resume normal operation
+		 */
+		babble_ctl = dsps_readb(musb->mregs, MUSB_BABBLE_CTL);
+		babble_ctl |= MUSB_BABBLE_FORCE_TXIDLE;
+		dsps_writeb(musb->mregs, MUSB_BABBLE_CTL, babble_ctl);
+
+		/* wait till line monitor flag cleared */
+		dev_dbg(musb->controller, "Set TXIDLE, wait J to clear\n");
+		do {
+			babble_ctl = dsps_readb(musb->mregs, MUSB_BABBLE_CTL);
+			udelay(1);
+		} while ((babble_ctl & MUSB_BABBLE_STUCK_J) && timeout--);
+
+		/* check whether stuck_at_j bit cleared */
+		if (babble_ctl & MUSB_BABBLE_STUCK_J) {
+			/*
+			 * real babble condition has occurred
+			 * restart the controller to start the
+			 * session again
+			 */
+			dev_dbg(musb->controller, "J not cleared, misc (%x)\n",
+				babble_ctl);
+			session_restart = true;
+		}
+	} else {
+		session_restart = true;
+	}
+
+	return session_restart;
+}
+
+static int dsps_musb_reset(struct musb *musb)
 {
 	struct device *dev = musb->controller;
 	struct dsps_glue *glue = dev_get_drvdata(dev->parent);
 	const struct dsps_musb_wrapper *wrp = glue->wrp;
+	int session_restart = 0;
+
+	if (glue->sw_babble_enabled)
+		session_restart = sw_babble_control(musb);
+	/*
+	 * In case of new silicon version babble condition can be recovered
+	 * without resetting the MUSB. But for older silicon versions, MUSB
+	 * reset is needed
+	 */
+	if (session_restart || !glue->sw_babble_enabled) {
+		dev_info(musb->controller, "Restarting MUSB to recover from Babble\n");
+		dsps_writel(musb->ctrl_base, wrp->control, (1 << wrp->reset));
+		usleep_range(100, 200);
+		usb_phy_shutdown(musb->xceiv);
+		usleep_range(100, 200);
+		usb_phy_init(musb->xceiv);
+		session_restart = 1;
+	}
 
-	dsps_writel(musb->ctrl_base, wrp->control, (1 << wrp->reset));
-	udelay(100);
+	return !session_restart;
 }
 
 static struct musb_platform_ops dsps_ops = {