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* [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements
@ 2015-01-21 19:31 Sylvain Rochet
  2015-01-21 19:31 ` [PATCHv5 1/4] USB: gadget: atmel_usba_udc: Fixed vbus_prev initial state Sylvain Rochet
                   ` (4 more replies)
  0 siblings, 5 replies; 7+ messages in thread
From: Sylvain Rochet @ 2015-01-21 19:31 UTC (permalink / raw)
  To: linux-arm-kernel

Start clocks on rising edge of the Vbus signal, stop clocks on falling 
edge of the Vbus signal.

Add suspend/resume with wakeup support.

Changes since v4:
  * Now using IRQ_NOAUTOEN flag to remove the unused check for 
    udc->driver is not NULL in the Vbus IRQ.
  * Reworked the start/stop of clocks on Vbus edges to prepare for 
    suspend/resume support, factorised start and stop procedures
  * New patch, suspend/resume for USBA with wakeup support

Changes since v3:
  * Added stable tag for the first patch
  * As suggested, removed the unused check for udc->driver is not NULL in
    Vbus IRQ by requesting IRQ after udc->driver is set and by releasing
    IRQ before udc->driver is cleared
  * Rebased the core patch of this series against the just explained changes

Changes since v2:
  * Use spin_lock_irqsave/unlock_irqrestore instead of spin_lock/unlock in
    threaded interrupt because we are not in irq context anymore
  * Removed useless and probably harmful IRQF_NO_SUSPEND from
    devm_request_threaded_irq() flags

Changes since v1:
  * Using a threaded irq and mutex instead of spinclock as suggested
  * Moved a silently fixed bug in a separate patch (1/2)

Sylvain Rochet (4):
  USB: gadget: atmel_usba_udc: Fixed vbus_prev initial state
  USB: gadget: atmel_usba_udc: Request an auto disabled Vbus signal IRQ
    instead of an auto enabled IRQ request followed by IRQ disable
  USB: gadget: atmel_usba_udc: Start clocks on rising edge of the Vbus
    signal, stop clocks on falling edge of the Vbus signal
  USB: gadget: atmel_usba_udc: Add suspend/resume with wakeup support

 drivers/usb/gadget/udc/atmel_usba_udc.c | 214 ++++++++++++++++++++++++--------
 drivers/usb/gadget/udc/atmel_usba_udc.h |   4 +
 2 files changed, 165 insertions(+), 53 deletions(-)

-- 
2.1.4

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCHv5 1/4] USB: gadget: atmel_usba_udc: Fixed vbus_prev initial state
  2015-01-21 19:31 [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements Sylvain Rochet
@ 2015-01-21 19:31 ` Sylvain Rochet
  2015-01-21 19:31 ` [PATCHv5 2/4] USB: gadget: atmel_usba_udc: Request an auto disabled Vbus signal IRQ instead of an auto enabled IRQ request followed by IRQ disable Sylvain Rochet
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 7+ messages in thread
From: Sylvain Rochet @ 2015-01-21 19:31 UTC (permalink / raw)
  To: linux-arm-kernel

If vbus gpio is high at init, we should set vbus_prev to true
accordingly to the current vbus state. Without that, we skip the first
vbus interrupt because the saved vbus state is not consistent.

Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Fixes: 914a3f3b3754 ("USB: add atmel_usba_udc driver")
Cc: <stable@vger.kernel.org> #2.6.24+
---
 drivers/usb/gadget/udc/atmel_usba_udc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c b/drivers/usb/gadget/udc/atmel_usba_udc.c
index ce88237..e207d75 100644
--- a/drivers/usb/gadget/udc/atmel_usba_udc.c
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
@@ -1791,6 +1791,8 @@ static int atmel_usba_start(struct usb_gadget *gadget,
 		toggle_bias(1);
 		usba_writel(udc, CTRL, USBA_ENABLE_MASK);
 		usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
+
+		udc->vbus_prev = 1;
 	}
 	spin_unlock_irqrestore(&udc->lock, flags);
 
-- 
2.1.4

^ permalink raw reply related	[flat|nested] 7+ messages in thread

* [PATCHv5 2/4] USB: gadget: atmel_usba_udc: Request an auto disabled Vbus signal IRQ instead of an auto enabled IRQ request followed by IRQ disable
  2015-01-21 19:31 [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements Sylvain Rochet
  2015-01-21 19:31 ` [PATCHv5 1/4] USB: gadget: atmel_usba_udc: Fixed vbus_prev initial state Sylvain Rochet
@ 2015-01-21 19:31 ` Sylvain Rochet
  2015-01-21 19:31 ` [PATCHv5 3/4] USB: gadget: atmel_usba_udc: Start clocks on rising edge of the Vbus signal, stop clocks on falling edge of the Vbus signal Sylvain Rochet
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 7+ messages in thread
From: Sylvain Rochet @ 2015-01-21 19:31 UTC (permalink / raw)
  To: linux-arm-kernel

Vbus IRQ handler needs a started UDC driver to work because it uses
udc->driver, which is set by the UDC start handler. The previous way
chosen was to return from interrupt if udc->driver is NULL using a
spinlock around the check.

We now request an auto disabled (IRQ_NOAUTOEN) Vbus signal IRQ instead
of an auto enabled IRQ followed by disable_irq(). This way we remove the
very small timeslot of enabled IRQ which existed previously between
request() and disable(). We don't need anymore to check if udc->driver
is NULL in IRQ handler.

Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
Suggested-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
 drivers/usb/gadget/udc/atmel_usba_udc.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c b/drivers/usb/gadget/udc/atmel_usba_udc.c
index e207d75..d369ae0 100644
--- a/drivers/usb/gadget/udc/atmel_usba_udc.c
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
@@ -1729,10 +1729,6 @@ static irqreturn_t usba_vbus_irq(int irq, void *devid)
 
 	spin_lock(&udc->lock);
 
-	/* May happen if Vbus pin toggles during probe() */
-	if (!udc->driver)
-		goto out;
-
 	vbus = vbus_is_present(udc);
 	if (vbus != udc->vbus_prev) {
 		if (vbus) {
@@ -1753,7 +1749,6 @@ static irqreturn_t usba_vbus_irq(int irq, void *devid)
 		udc->vbus_prev = vbus;
 	}
 
-out:
 	spin_unlock(&udc->lock);
 
 	return IRQ_HANDLED;
@@ -2049,6 +2044,7 @@ static int usba_udc_probe(struct platform_device *pdev)
 
 	if (gpio_is_valid(udc->vbus_pin)) {
 		if (!devm_gpio_request(&pdev->dev, udc->vbus_pin, "atmel_usba_udc")) {
+			irq_set_status_flags(gpio_to_irq(udc->vbus_pin), IRQ_NOAUTOEN);
 			ret = devm_request_irq(&pdev->dev,
 					gpio_to_irq(udc->vbus_pin),
 					usba_vbus_irq, 0,
@@ -2058,8 +2054,6 @@ static int usba_udc_probe(struct platform_device *pdev)
 				dev_warn(&udc->pdev->dev,
 					 "failed to request vbus irq; "
 					 "assuming always on\n");
-			} else {
-				disable_irq(gpio_to_irq(udc->vbus_pin));
 			}
 		} else {
 			/* gpio_request fail so use -EINVAL for gpio_is_valid */
-- 
2.1.4

^ permalink raw reply related	[flat|nested] 7+ messages in thread

* [PATCHv5 3/4] USB: gadget: atmel_usba_udc: Start clocks on rising edge of the Vbus signal, stop clocks on falling edge of the Vbus signal
  2015-01-21 19:31 [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements Sylvain Rochet
  2015-01-21 19:31 ` [PATCHv5 1/4] USB: gadget: atmel_usba_udc: Fixed vbus_prev initial state Sylvain Rochet
  2015-01-21 19:31 ` [PATCHv5 2/4] USB: gadget: atmel_usba_udc: Request an auto disabled Vbus signal IRQ instead of an auto enabled IRQ request followed by IRQ disable Sylvain Rochet
@ 2015-01-21 19:31 ` Sylvain Rochet
  2015-01-21 19:31 ` [PATCHv5 4/4] USB: gadget: atmel_usba_udc: Add suspend/resume with wakeup support Sylvain Rochet
  2015-01-21 20:46 ` [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements Boris Brezillon
  4 siblings, 0 replies; 7+ messages in thread
From: Sylvain Rochet @ 2015-01-21 19:31 UTC (permalink / raw)
  To: linux-arm-kernel

If USB PLL is not necessary for other USB drivers (e.g. OHCI and EHCI)
we will reduce power consumption by switching off the USB PLL if no USB
Host is currently connected to this USB Device.

We are using Vbus GPIO signal to detect Host presence. If Vbus signal is
not available then the device stays continuously clocked.

Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 drivers/usb/gadget/udc/atmel_usba_udc.c | 149 +++++++++++++++++++++-----------
 drivers/usb/gadget/udc/atmel_usba_udc.h |   4 +
 2 files changed, 104 insertions(+), 49 deletions(-)

diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c b/drivers/usb/gadget/udc/atmel_usba_udc.c
index d369ae0..963e398 100644
--- a/drivers/usb/gadget/udc/atmel_usba_udc.c
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
@@ -1719,38 +1719,98 @@ static irqreturn_t usba_udc_irq(int irq, void *devid)
 	return IRQ_HANDLED;
 }
 
-static irqreturn_t usba_vbus_irq(int irq, void *devid)
+static int start_clock(struct usba_udc *udc)
+{
+	int ret;
+
+	if (udc->clocked)
+		return 0;
+
+	ret = clk_prepare_enable(udc->pclk);
+	if (ret)
+		return ret;
+	ret = clk_prepare_enable(udc->hclk);
+	if (ret) {
+		clk_disable_unprepare(udc->pclk);
+		return ret;
+	}
+
+	udc->clocked = true;
+	return 0;
+}
+
+static void stop_clock(struct usba_udc *udc)
+{
+	if (!udc->clocked)
+		return;
+
+	clk_disable_unprepare(udc->hclk);
+	clk_disable_unprepare(udc->pclk);
+
+	udc->clocked = false;
+}
+
+static int usba_start(struct usba_udc *udc)
+{
+	unsigned long flags;
+	int ret;
+
+	ret = start_clock(udc);
+	if (ret)
+		return ret;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	toggle_bias(1);
+	usba_writel(udc, CTRL, USBA_ENABLE_MASK);
+	usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return 0;
+}
+
+static void usba_stop(struct usba_udc *udc)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&udc->lock, flags);
+	udc->gadget.speed = USB_SPEED_UNKNOWN;
+	reset_all_endpoints(udc);
+
+	/* This will also disable the DP pullup */
+	toggle_bias(0);
+	usba_writel(udc, CTRL, USBA_DISABLE_MASK);
+	spin_unlock_irqrestore(&udc->lock, flags);
+
+	stop_clock(udc);
+}
+
+static irqreturn_t usba_vbus_irq_thread(int irq, void *devid)
 {
 	struct usba_udc *udc = devid;
 	int vbus;
+	int ret;
 
 	/* debounce */
 	udelay(10);
 
-	spin_lock(&udc->lock);
+	mutex_lock(&udc->vbus_mutex);
 
 	vbus = vbus_is_present(udc);
 	if (vbus != udc->vbus_prev) {
+		udc->vbus_prev = vbus;
 		if (vbus) {
-			toggle_bias(1);
-			usba_writel(udc, CTRL, USBA_ENABLE_MASK);
-			usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
+			ret = usba_start(udc);
+			if (ret)
+				goto out;
 		} else {
-			udc->gadget.speed = USB_SPEED_UNKNOWN;
-			reset_all_endpoints(udc);
-			toggle_bias(0);
-			usba_writel(udc, CTRL, USBA_DISABLE_MASK);
-			if (udc->driver->disconnect) {
-				spin_unlock(&udc->lock);
+			usba_stop(udc);
+
+			if (udc->driver->disconnect)
 				udc->driver->disconnect(&udc->gadget);
-				spin_lock(&udc->lock);
-			}
 		}
-		udc->vbus_prev = vbus;
 	}
 
-	spin_unlock(&udc->lock);
-
+out:
+	mutex_unlock(&udc->vbus_mutex);
 	return IRQ_HANDLED;
 }
 
@@ -1762,57 +1822,47 @@ static int atmel_usba_start(struct usb_gadget *gadget,
 	unsigned long flags;
 
 	spin_lock_irqsave(&udc->lock, flags);
-
 	udc->devstatus = 1 << USB_DEVICE_SELF_POWERED;
 	udc->driver = driver;
 	spin_unlock_irqrestore(&udc->lock, flags);
 
-	ret = clk_prepare_enable(udc->pclk);
-	if (ret)
-		return ret;
-	ret = clk_prepare_enable(udc->hclk);
-	if (ret) {
-		clk_disable_unprepare(udc->pclk);
-		return ret;
-	}
+	mutex_lock(&udc->vbus_mutex);
 
-	udc->vbus_prev = 0;
 	if (gpio_is_valid(udc->vbus_pin))
 		enable_irq(gpio_to_irq(udc->vbus_pin));
 
 	/* If Vbus is present, enable the controller and wait for reset */
-	spin_lock_irqsave(&udc->lock, flags);
-	if (vbus_is_present(udc) && udc->vbus_prev == 0) {
-		toggle_bias(1);
-		usba_writel(udc, CTRL, USBA_ENABLE_MASK);
-		usba_writel(udc, INT_ENB, USBA_END_OF_RESET);
-
-		udc->vbus_prev = 1;
+	udc->vbus_prev = vbus_is_present(udc);
+	if (udc->vbus_prev) {
+		ret = usba_start(udc);
+		if (ret)
+			goto err;
 	}
-	spin_unlock_irqrestore(&udc->lock, flags);
 
+	mutex_unlock(&udc->vbus_mutex);
 	return 0;
+
+err:
+	if (gpio_is_valid(udc->vbus_pin))
+		disable_irq(gpio_to_irq(udc->vbus_pin));
+
+	mutex_unlock(&udc->vbus_mutex);
+
+	spin_lock_irqsave(&udc->lock, flags);
+	udc->devstatus &= ~(1 << USB_DEVICE_SELF_POWERED);
+	udc->driver = NULL;
+	spin_unlock_irqrestore(&udc->lock, flags);
+	return ret;
 }
 
 static int atmel_usba_stop(struct usb_gadget *gadget)
 {
 	struct usba_udc *udc = container_of(gadget, struct usba_udc, gadget);
-	unsigned long flags;
 
 	if (gpio_is_valid(udc->vbus_pin))
 		disable_irq(gpio_to_irq(udc->vbus_pin));
 
-	spin_lock_irqsave(&udc->lock, flags);
-	udc->gadget.speed = USB_SPEED_UNKNOWN;
-	reset_all_endpoints(udc);
-	spin_unlock_irqrestore(&udc->lock, flags);
-
-	/* This will also disable the DP pullup */
-	toggle_bias(0);
-	usba_writel(udc, CTRL, USBA_DISABLE_MASK);
-
-	clk_disable_unprepare(udc->hclk);
-	clk_disable_unprepare(udc->pclk);
+	usba_stop(udc);
 
 	udc->driver = NULL;
 
@@ -1992,6 +2042,7 @@ static int usba_udc_probe(struct platform_device *pdev)
 		return PTR_ERR(hclk);
 
 	spin_lock_init(&udc->lock);
+	mutex_init(&udc->vbus_mutex);
 	udc->pdev = pdev;
 	udc->pclk = pclk;
 	udc->hclk = hclk;
@@ -2045,9 +2096,9 @@ static int usba_udc_probe(struct platform_device *pdev)
 	if (gpio_is_valid(udc->vbus_pin)) {
 		if (!devm_gpio_request(&pdev->dev, udc->vbus_pin, "atmel_usba_udc")) {
 			irq_set_status_flags(gpio_to_irq(udc->vbus_pin), IRQ_NOAUTOEN);
-			ret = devm_request_irq(&pdev->dev,
-					gpio_to_irq(udc->vbus_pin),
-					usba_vbus_irq, 0,
+			ret = devm_request_threaded_irq(&pdev->dev,
+					gpio_to_irq(udc->vbus_pin), NULL,
+					usba_vbus_irq_thread, IRQF_ONESHOT,
 					"atmel_usba_udc", udc);
 			if (ret) {
 				udc->vbus_pin = -ENODEV;
diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.h b/drivers/usb/gadget/udc/atmel_usba_udc.h
index a70706e..3ceed76 100644
--- a/drivers/usb/gadget/udc/atmel_usba_udc.h
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.h
@@ -308,6 +308,9 @@ struct usba_udc {
 	/* Protect hw registers from concurrent modifications */
 	spinlock_t lock;
 
+	/* Mutex to prevent concurrent start or stop */
+	struct mutex vbus_mutex;
+
 	void __iomem *regs;
 	void __iomem *fifo;
 
@@ -321,6 +324,7 @@ struct usba_udc {
 	struct clk *pclk;
 	struct clk *hclk;
 	struct usba_ep *usba_ep;
+	bool clocked;
 
 	u16 devstatus;
 
-- 
2.1.4

^ permalink raw reply related	[flat|nested] 7+ messages in thread

* [PATCHv5 4/4] USB: gadget: atmel_usba_udc: Add suspend/resume with wakeup support
  2015-01-21 19:31 [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements Sylvain Rochet
                   ` (2 preceding siblings ...)
  2015-01-21 19:31 ` [PATCHv5 3/4] USB: gadget: atmel_usba_udc: Start clocks on rising edge of the Vbus signal, stop clocks on falling edge of the Vbus signal Sylvain Rochet
@ 2015-01-21 19:31 ` Sylvain Rochet
  2015-01-21 19:58   ` Boris Brezillon
  2015-01-21 20:46 ` [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements Boris Brezillon
  4 siblings, 1 reply; 7+ messages in thread
From: Sylvain Rochet @ 2015-01-21 19:31 UTC (permalink / raw)
  To: linux-arm-kernel

This patch add suspend/resume with wakeup support for Atmel USBA.

On suspend: We stay continuously clocked if Vbus signal is not
available. If Vbus signal is available we set the Vbus signal as a wake
up source then we stop the USBA itself and all clocks used by USBA.

On resume: We recover clocks and USBA we stopped them. If a device is
connected, i.e. connected while we were suspended without wakeup
enabled, we enable the controller.

Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
---
 drivers/usb/gadget/udc/atmel_usba_udc.c | 61 +++++++++++++++++++++++++++++++++
 1 file changed, 61 insertions(+)

diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c b/drivers/usb/gadget/udc/atmel_usba_udc.c
index 963e398..326725e 100644
--- a/drivers/usb/gadget/udc/atmel_usba_udc.c
+++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
@@ -2115,6 +2115,7 @@ static int usba_udc_probe(struct platform_device *pdev)
 	ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
 	if (ret)
 		return ret;
+	device_init_wakeup(&pdev->dev, 1);
 
 	usba_init_debugfs(udc);
 	for (i = 1; i < udc->num_ep; i++)
@@ -2130,6 +2131,7 @@ static int __exit usba_udc_remove(struct platform_device *pdev)
 
 	udc = platform_get_drvdata(pdev);
 
+	device_init_wakeup(&pdev->dev, 0);
 	usb_del_gadget_udc(&udc->gadget);
 
 	for (i = 1; i < udc->num_ep; i++)
@@ -2139,6 +2141,62 @@ static int __exit usba_udc_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int usba_udc_suspend(struct device *dev)
+{
+	struct usba_udc *udc = dev_get_drvdata(dev);
+
+	/* Not started */
+	if (!udc->driver)
+		return 0;
+
+	if (!device_may_wakeup(dev)) {
+		usba_stop(udc);
+		return 0;
+	}
+
+	/*
+	 * Device may wake up. We stay clocked if we failed
+	 * to request vbus irq, assuming always on.
+	 */
+	if (gpio_is_valid(udc->vbus_pin)) {
+		usba_stop(udc);
+		/* Only wake up on device connection */
+		irq_set_irq_type(gpio_to_irq(udc->vbus_pin),
+			udc->vbus_pin_inverted ?
+			IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING);
+		enable_irq_wake(gpio_to_irq(udc->vbus_pin));
+	}
+
+	return 0;
+}
+
+static int usba_udc_resume(struct device *dev)
+{
+	struct usba_udc *udc = dev_get_drvdata(dev);
+
+	/* Not started */
+	if (!udc->driver)
+		return 0;
+
+	if (device_may_wakeup(dev) && gpio_is_valid(udc->vbus_pin)) {
+		disable_irq_wake(gpio_to_irq(udc->vbus_pin));
+		irq_set_irq_type(gpio_to_irq(udc->vbus_pin), IRQ_TYPE_EDGE_BOTH);
+	}
+
+	/* If Vbus is present, enable the controller and wait for reset */
+	mutex_lock(&udc->vbus_mutex);
+	udc->vbus_prev = vbus_is_present(udc);
+
+	if (udc->vbus_prev)
+		usba_start(udc);
+
+	mutex_unlock(&udc->vbus_mutex);
+
+	return 0;
+}
+#endif
+
 #if defined(CONFIG_OF)
 static const struct of_device_id atmel_udc_dt_ids[] = {
 	{ .compatible = "atmel,at91sam9rl-udc" },
@@ -2148,10 +2206,13 @@ static const struct of_device_id atmel_udc_dt_ids[] = {
 MODULE_DEVICE_TABLE(of, atmel_udc_dt_ids);
 #endif
 
+static SIMPLE_DEV_PM_OPS(usba_udc_pm_ops, usba_udc_suspend, usba_udc_resume);
+
 static struct platform_driver udc_driver = {
 	.remove		= __exit_p(usba_udc_remove),
 	.driver		= {
 		.name		= "atmel_usba_udc",
+		.pm		= &usba_udc_pm_ops,
 		.of_match_table	= of_match_ptr(atmel_udc_dt_ids),
 	},
 };
-- 
2.1.4

^ permalink raw reply related	[flat|nested] 7+ messages in thread

* [PATCHv5 4/4] USB: gadget: atmel_usba_udc: Add suspend/resume with wakeup support
  2015-01-21 19:31 ` [PATCHv5 4/4] USB: gadget: atmel_usba_udc: Add suspend/resume with wakeup support Sylvain Rochet
@ 2015-01-21 19:58   ` Boris Brezillon
  0 siblings, 0 replies; 7+ messages in thread
From: Boris Brezillon @ 2015-01-21 19:58 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Sylvain,

On Wed, 21 Jan 2015 20:31:14 +0100
Sylvain Rochet <sylvain.rochet@finsecur.com> wrote:

> This patch add suspend/resume with wakeup support for Atmel USBA.
> 
> On suspend: We stay continuously clocked if Vbus signal is not
> available. If Vbus signal is available we set the Vbus signal as a wake
> up source then we stop the USBA itself and all clocks used by USBA.
> 
> On resume: We recover clocks and USBA we stopped them. If a device is
> connected, i.e. connected while we were suspended without wakeup
> enabled, we enable the controller.
> 
> Signed-off-by: Sylvain Rochet <sylvain.rochet@finsecur.com>
> ---
>  drivers/usb/gadget/udc/atmel_usba_udc.c | 61 +++++++++++++++++++++++++++++++++
>  1 file changed, 61 insertions(+)
> 
> diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c b/drivers/usb/gadget/udc/atmel_usba_udc.c
> index 963e398..326725e 100644
> --- a/drivers/usb/gadget/udc/atmel_usba_udc.c
> +++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
> @@ -2115,6 +2115,7 @@ static int usba_udc_probe(struct platform_device *pdev)
>  	ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
>  	if (ret)
>  		return ret;
> +	device_init_wakeup(&pdev->dev, 1);
>  
>  	usba_init_debugfs(udc);
>  	for (i = 1; i < udc->num_ep; i++)
> @@ -2130,6 +2131,7 @@ static int __exit usba_udc_remove(struct platform_device *pdev)
>  
>  	udc = platform_get_drvdata(pdev);
>  
> +	device_init_wakeup(&pdev->dev, 0);
>  	usb_del_gadget_udc(&udc->gadget);
>  
>  	for (i = 1; i < udc->num_ep; i++)
> @@ -2139,6 +2141,62 @@ static int __exit usba_udc_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +#ifdef CONFIG_PM
> +static int usba_udc_suspend(struct device *dev)
> +{
> +	struct usba_udc *udc = dev_get_drvdata(dev);
> +
> +	/* Not started */
> +	if (!udc->driver)
> +		return 0;
> +
> +	if (!device_may_wakeup(dev)) {
> +		usba_stop(udc);
> +		return 0;
> +	}
> +
> +	/*
> +	 * Device may wake up. We stay clocked if we failed
> +	 * to request vbus irq, assuming always on.
> +	 */
> +	if (gpio_is_valid(udc->vbus_pin)) {
> +		usba_stop(udc);
> +		/* Only wake up on device connection */
> +		irq_set_irq_type(gpio_to_irq(udc->vbus_pin),
> +			udc->vbus_pin_inverted ?
> +			IRQ_TYPE_EDGE_FALLING : IRQ_TYPE_EDGE_RISING);

If I'm correct, you're testing on a at91sam9x5 platform. Be careful,
this driver is used by older SoCs (at91sam9rl and avr32 SoCs) which do
not support configuring the interrupt on a specific edge (they trigger
on both edges).

This leaves two solutions here:
1) keep the IRQ_TYPE_EDGE_BOTH setting.
2) add new compatible strings to this driver and make this specific
edge change dependent on the SoC capability.

Best Regards,

Boris

-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements
  2015-01-21 19:31 [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements Sylvain Rochet
                   ` (3 preceding siblings ...)
  2015-01-21 19:31 ` [PATCHv5 4/4] USB: gadget: atmel_usba_udc: Add suspend/resume with wakeup support Sylvain Rochet
@ 2015-01-21 20:46 ` Boris Brezillon
  4 siblings, 0 replies; 7+ messages in thread
From: Boris Brezillon @ 2015-01-21 20:46 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Sylvain,

On Wed, 21 Jan 2015 20:31:10 +0100
Sylvain Rochet <sylvain.rochet@finsecur.com> wrote:

> Start clocks on rising edge of the Vbus signal, stop clocks on falling 
> edge of the Vbus signal.
> 
> Add suspend/resume with wakeup support.

Apart from the minor comment I made on patch 4, you can add my:

Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>

to the whole series.

Thanks for your patience.

Best Regards,

Boris

> 
> Changes since v4:
>   * Now using IRQ_NOAUTOEN flag to remove the unused check for 
>     udc->driver is not NULL in the Vbus IRQ.
>   * Reworked the start/stop of clocks on Vbus edges to prepare for 
>     suspend/resume support, factorised start and stop procedures
>   * New patch, suspend/resume for USBA with wakeup support
> 
> Changes since v3:
>   * Added stable tag for the first patch
>   * As suggested, removed the unused check for udc->driver is not NULL in
>     Vbus IRQ by requesting IRQ after udc->driver is set and by releasing
>     IRQ before udc->driver is cleared
>   * Rebased the core patch of this series against the just explained changes
> 
> Changes since v2:
>   * Use spin_lock_irqsave/unlock_irqrestore instead of spin_lock/unlock in
>     threaded interrupt because we are not in irq context anymore
>   * Removed useless and probably harmful IRQF_NO_SUSPEND from
>     devm_request_threaded_irq() flags
> 
> Changes since v1:
>   * Using a threaded irq and mutex instead of spinclock as suggested
>   * Moved a silently fixed bug in a separate patch (1/2)
> 
> Sylvain Rochet (4):
>   USB: gadget: atmel_usba_udc: Fixed vbus_prev initial state
>   USB: gadget: atmel_usba_udc: Request an auto disabled Vbus signal IRQ
>     instead of an auto enabled IRQ request followed by IRQ disable
>   USB: gadget: atmel_usba_udc: Start clocks on rising edge of the Vbus
>     signal, stop clocks on falling edge of the Vbus signal
>   USB: gadget: atmel_usba_udc: Add suspend/resume with wakeup support
> 
>  drivers/usb/gadget/udc/atmel_usba_udc.c | 214 ++++++++++++++++++++++++--------
>  drivers/usb/gadget/udc/atmel_usba_udc.h |   4 +
>  2 files changed, 165 insertions(+), 53 deletions(-)
> 



-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2015-01-21 20:46 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-01-21 19:31 [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements Sylvain Rochet
2015-01-21 19:31 ` [PATCHv5 1/4] USB: gadget: atmel_usba_udc: Fixed vbus_prev initial state Sylvain Rochet
2015-01-21 19:31 ` [PATCHv5 2/4] USB: gadget: atmel_usba_udc: Request an auto disabled Vbus signal IRQ instead of an auto enabled IRQ request followed by IRQ disable Sylvain Rochet
2015-01-21 19:31 ` [PATCHv5 3/4] USB: gadget: atmel_usba_udc: Start clocks on rising edge of the Vbus signal, stop clocks on falling edge of the Vbus signal Sylvain Rochet
2015-01-21 19:31 ` [PATCHv5 4/4] USB: gadget: atmel_usba_udc: Add suspend/resume with wakeup support Sylvain Rochet
2015-01-21 19:58   ` Boris Brezillon
2015-01-21 20:46 ` [PATCHv5 0/4] USB: gadget: atmel_usba_udc: Driver improvements Boris Brezillon

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