usb: musb: Add PM runtime support for MUSB DSPS glue layer

We can now just use PM runtime autoidle support as musb core
keeps things enabled when the devctl session bit is set. And
there's no need for dsps_musb_try_idle() so let's just remove
it.

Note that as cppi41 dma is clocked by musb, this only makes
PM work for dsps glue layer if CONFIG_MUSB_PIO_ONLY=y and
cppi41.ko is unloaded. This will get fixed when cppi41.c has
PM runtime implemented.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/musb/musb_dsps.c

@@ -145,43 +145,6 @@ static const struct debugfs_reg32 dsps_musb_regs[] = {
 	{ "mode",		0xe8 },
 };
 
-static void dsps_musb_try_idle(struct musb *musb, unsigned long timeout)
-{
-	struct device *dev = musb->controller;
-	struct dsps_glue *glue = dev_get_drvdata(dev->parent);
-
-	if (timeout == 0)
-		timeout = jiffies + msecs_to_jiffies(3);
-
-	/* Never idle if active, or when VBUS timeout is not set as host */
-	if (musb->is_active || (musb->a_wait_bcon == 0 &&
-			musb->xceiv->otg->state == OTG_STATE_A_WAIT_BCON)) {
-		dev_dbg(musb->controller, "%s active, deleting timer\n",
-				usb_otg_state_string(musb->xceiv->otg->state));
-		del_timer(&glue->timer);
-		glue->last_timer = jiffies;
-		return;
-	}
-	if (musb->port_mode != MUSB_PORT_MODE_DUAL_ROLE)
-		return;
-
-	if (!musb->g.dev.driver)
-		return;
-
-	if (time_after(glue->last_timer, timeout) &&
-				timer_pending(&glue->timer)) {
-		dev_dbg(musb->controller,
-			"Longer idle timer already pending, ignoring...\n");
-		return;
-	}
-	glue->last_timer = timeout;
-
-	dev_dbg(musb->controller, "%s inactive, starting idle timer for %u ms\n",
-		usb_otg_state_string(musb->xceiv->otg->state),
-			jiffies_to_msecs(timeout - jiffies));
-	mod_timer(&glue->timer, timeout);
-}
-
 /**
  * dsps_musb_enable - enable interrupts
  */
@@ -206,7 +169,6 @@ static void dsps_musb_enable(struct musb *musb)
 			musb->port_mode == MUSB_PORT_MODE_DUAL_ROLE)
 		mod_timer(&glue->timer, jiffies +
 				msecs_to_jiffies(wrp->poll_timeout));
-	dsps_musb_try_idle(musb, 0);
 }
 
 /**
@@ -236,6 +198,11 @@ static void otg_timer(unsigned long _musb)
 	u8 devctl;
 	unsigned long flags;
 	int skip_session = 0;
+	int err;
+
+	err = pm_runtime_get_sync(dev);
+	if (err < 0)
+		dev_err(dev, "Poll could not pm_runtime_get: %i\n", err);
 
 	/*
 	 * We poll because DSPS IP's won't expose several OTG-critical
@@ -279,6 +246,9 @@ static void otg_timer(unsigned long _musb)
 		break;
 	}
 	spin_unlock_irqrestore(&musb->lock, flags);
+
+	pm_runtime_mark_last_busy(dev);
+	pm_runtime_put_autosuspend(dev);
 }
 
 static irqreturn_t dsps_interrupt(int irq, void *hci)
@@ -634,7 +604,6 @@ static struct musb_platform_ops dsps_ops = {
 	.enable		= dsps_musb_enable,
 	.disable	= dsps_musb_disable,
 
-	.try_idle	= dsps_musb_try_idle,
 	.set_mode	= dsps_musb_set_mode,
 	.recover	= dsps_musb_recover,
 };
@@ -798,6 +767,8 @@ static int dsps_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, glue);
 	pm_runtime_enable(&pdev->dev);
+	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_set_autosuspend_delay(&pdev->dev, 200);
 
 	ret = pm_runtime_get_sync(&pdev->dev);
 	if (ret < 0) {
@@ -809,11 +780,15 @@ static int dsps_probe(struct platform_device *pdev)
 	if (ret)
 		goto err3;
 
+	pm_runtime_mark_last_busy(&pdev->dev);
+	pm_runtime_put_autosuspend(&pdev->dev);
+
 	return 0;
 
 err3:
-	pm_runtime_put(&pdev->dev);
+	pm_runtime_put_sync(&pdev->dev);
 err2:
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	return ret;
 }
@@ -825,7 +800,8 @@ static int dsps_remove(struct platform_device *pdev)
 	platform_device_unregister(glue->musb);
 
 	/* disable usbss clocks */
-	pm_runtime_put(&pdev->dev);
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
+	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
 	return 0;