[PATCH AUTOSEL 5.2 010/171] usb: core: hub: Disable hub-initiated U1/U2

[PATCH AUTOSEL 5.2 010/171] usb: core: hub: Disable hub-initiated U1/U2

[Sasha Levin]

From: Thinh Nguyen <Thinh.Nguyen@synopsys.com>

[ Upstream commit 561759292774707b71ee61aecc07724905bb7ef1 ]

If the device rejects the control transfer to enable device-initiated
U1/U2 entry, then the device will not initiate U1/U2 transition. To
improve the performance, the downstream port should not initate
transition to U1/U2 to avoid the delay from the device link command
response (no packet can be transmitted while waiting for a response from
the device). If the device has some quirks and does not implement U1/U2,
it may reject all the link state change requests, and the downstream
port may resend and flood the bus with more requests. This will affect
the device performance even further. This patch disables the
hub-initated U1/U2 if the device-initiated U1/U2 entry fails.

Reference: USB 3.2 spec 7.2.4.2.3

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/core/hub.c | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 2f94568ba385..79a9f0302ff6 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -3999,6 +3999,9 @@ static int usb_set_lpm_timeout(struct usb_device *udev,
  * control transfers to set the hub timeout or enable device-initiated U1/U2
  * will be successful.
  *
+ * If the control transfer to enable device-initiated U1/U2 entry fails, then
+ * hub-initiated U1/U2 will be disabled.
+ *
  * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
  * driver know about it.  If that call fails, it should be harmless, and just
  * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
@@ -4053,23 +4056,24 @@ static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
 		 * host know that this link state won't be enabled.
 		 */
 		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
-	} else {
-		/* Only a configured device will accept the Set Feature
-		 * U1/U2_ENABLE
-		 */
-		if (udev->actconfig)
-			usb_set_device_initiated_lpm(udev, state, true);
+		return;
+	}
 
-		/* As soon as usb_set_lpm_timeout(timeout) returns 0, the
-		 * hub-initiated LPM is enabled. Thus, LPM is enabled no
-		 * matter the result of usb_set_device_initiated_lpm().
-		 * The only difference is whether device is able to initiate
-		 * LPM.
-		 */
+	/* Only a configured device will accept the Set Feature
+	 * U1/U2_ENABLE
+	 */
+	if (udev->actconfig &&
+	    usb_set_device_initiated_lpm(udev, state, true) == 0) {
 		if (state == USB3_LPM_U1)
 			udev->usb3_lpm_u1_enabled = 1;
 		else if (state == USB3_LPM_U2)
 			udev->usb3_lpm_u2_enabled = 1;
+	} else {
+		/* Don't request U1/U2 entry if the device
+		 * cannot transition to U1/U2.
+		 */
+		usb_set_lpm_timeout(udev, state, 0);
+		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
 	}
 }
 
-- 
2.20.1

[PATCH AUTOSEL 5.2 069/171] usb: gadget: Zero ffs_io_data

[Sasha Levin]

From: Andrzej Pietrasiewicz <andrzej.p@collabora.com>

[ Upstream commit 508595515f4bcfe36246e4a565cf280937aeaade ]

In some cases the "Allocate & copy" block in ffs_epfile_io() is not
executed. Consequently, in such a case ffs_alloc_buffer() is never called
and struct ffs_io_data is not initialized properly. This in turn leads to
problems when ffs_free_buffer() is called at the end of ffs_epfile_io().

This patch uses kzalloc() instead of kmalloc() in the aio case and memset()
in non-aio case to properly initialize struct ffs_io_data.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/gadget/function/f_fs.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index c7ed90084d1a..213ff03c8a9f 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1183,11 +1183,12 @@ static ssize_t ffs_epfile_write_iter(struct kiocb *kiocb, struct iov_iter *from)
 	ENTER();
 
 	if (!is_sync_kiocb(kiocb)) {
-		p = kmalloc(sizeof(io_data), GFP_KERNEL);
+		p = kzalloc(sizeof(io_data), GFP_KERNEL);
 		if (unlikely(!p))
 			return -ENOMEM;
 		p->aio = true;
 	} else {
+		memset(p, 0, sizeof(*p));
 		p->aio = false;
 	}
 
@@ -1219,11 +1220,12 @@ static ssize_t ffs_epfile_read_iter(struct kiocb *kiocb, struct iov_iter *to)
 	ENTER();
 
 	if (!is_sync_kiocb(kiocb)) {
-		p = kmalloc(sizeof(io_data), GFP_KERNEL);
+		p = kzalloc(sizeof(io_data), GFP_KERNEL);
 		if (unlikely(!p))
 			return -ENOMEM;
 		p->aio = true;
 	} else {
+		memset(p, 0, sizeof(*p));
 		p->aio = false;
 	}
 
-- 
2.20.1

[PATCH AUTOSEL 5.2 070/171] usb: dwc3: Fix core validation in probe, move after clocks are enabled

[Sasha Levin]

From: Enric Balletbo i Serra <enric.balletbo@collabora.com>

[ Upstream commit dc1b5d9aed1794b5a1c6b0da46e372cc09974cbc ]

The required clocks needs to be enabled before the first register
access. After commit fe8abf332b8f ("usb: dwc3: support clocks and resets
for DWC3 core"), this happens when the dwc3_core_is_valid function is
called, but the mentioned commit adds that call in the wrong place,
before the clocks are enabled. So, move that call after the
clk_bulk_enable() to ensure the clocks are enabled and the reset
deasserted.

I detected this while, as experiment, I tried to move the clocks and resets
from the glue layer to the DWC3 core on a Samsung Chromebook Plus.

That was not detected before because, in most cases, the glue layer
initializes SoC-specific things and then populates the child "snps,dwc3"
with those clocks already enabled.

Fixes: b873e2d0ea1ef ("usb: dwc3: Do core validation early on probe")
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/dwc3/core.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 4aff1d8dbc4f..6e9e172010fc 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1423,11 +1423,6 @@ static int dwc3_probe(struct platform_device *pdev)
 	dwc->regs	= regs;
 	dwc->regs_size	= resource_size(&dwc_res);
 
-	if (!dwc3_core_is_valid(dwc)) {
-		dev_err(dwc->dev, "this is not a DesignWare USB3 DRD Core\n");
-		return -ENODEV;
-	}
-
 	dwc3_get_properties(dwc);
 
 	dwc->reset = devm_reset_control_get_optional_shared(dev, NULL);
@@ -1460,6 +1455,12 @@ static int dwc3_probe(struct platform_device *pdev)
 	if (ret)
 		goto unprepare_clks;
 
+	if (!dwc3_core_is_valid(dwc)) {
+		dev_err(dwc->dev, "this is not a DesignWare USB3 DRD Core\n");
+		ret = -ENODEV;
+		goto disable_clks;
+	}
+
 	platform_set_drvdata(pdev, dwc);
 	dwc3_cache_hwparams(dwc);
 
@@ -1525,6 +1526,7 @@ static int dwc3_probe(struct platform_device *pdev)
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 
+disable_clks:
 	clk_bulk_disable(dwc->num_clks, dwc->clks);
 unprepare_clks:
 	clk_bulk_unprepare(dwc->num_clks, dwc->clks);
-- 
2.20.1

[PATCH AUTOSEL 5.2 072/171] usb: gadget: storage: Remove warning message

[Sasha Levin]

From: EJ Hsu <ejh@nvidia.com>

[ Upstream commit e70b3f5da00119e057b7faa557753fee7f786f17 ]

This change is to fix below warning message in following scenario:
usb_composite_setup_continue: Unexpected call

When system tried to enter suspend, the fsg_disable() will be called to
disable fsg driver and send a signal to fsg_main_thread. However, at
this point, the fsg_main_thread has already been frozen and can not
respond to this signal. So, this signal will be pended until
fsg_main_thread wakes up.

Once system resumes from suspend, fsg_main_thread will detect a signal
pended and do some corresponding action (in handle_exception()). Then,
host will send some setup requests (get descriptor, set configuration...)
to UDC driver trying to enumerate this device. During the handling of "set
configuration" request, it will try to sync up with fsg_main_thread by
sending a signal (which is the same as the signal sent by fsg_disable)
to it. In a similar manner, once the fsg_main_thread receives this
signal, it will call handle_exception() to handle the request.

However, if the fsg_main_thread wakes up from suspend a little late and
"set configuration" request from Host arrives a little earlier,
fsg_main_thread might come across the request from "set configuration"
when it handles the signal from fsg_disable(). In this case, it will
handle this request as well. So, when fsg_main_thread tries to handle
the signal sent from "set configuration" later, there will nothing left
to do and warning message "Unexpected call" is printed.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: EJ Hsu <ejh@nvidia.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/usb/gadget/function/f_mass_storage.c | 21 ++++++++++++++------
 drivers/usb/gadget/function/storage_common.h |  1 +
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
index 043f97ad8f22..982c3e89eb0d 100644
--- a/drivers/usb/gadget/function/f_mass_storage.c
+++ b/drivers/usb/gadget/function/f_mass_storage.c
@@ -2293,8 +2293,7 @@ static int fsg_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 static void fsg_disable(struct usb_function *f)
 {
 	struct fsg_dev *fsg = fsg_from_func(f);
-	fsg->common->new_fsg = NULL;
-	raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
+	raise_exception(fsg->common, FSG_STATE_DISCONNECT);
 }
 
 
@@ -2307,6 +2306,7 @@ static void handle_exception(struct fsg_common *common)
 	enum fsg_state		old_state;
 	struct fsg_lun		*curlun;
 	unsigned int		exception_req_tag;
+	struct fsg_dev		*fsg;
 
 	/*
 	 * Clear the existing signals.  Anything but SIGUSR1 is converted
@@ -2413,9 +2413,19 @@ static void handle_exception(struct fsg_common *common)
 		break;
 
 	case FSG_STATE_CONFIG_CHANGE:
-		do_set_interface(common, common->new_fsg);
-		if (common->new_fsg)
+		fsg = common->new_fsg;
+		/*
+		 * Add a check here to double confirm if a disconnect event
+		 * occurs and common->new_fsg has been cleared.
+		 */
+		if (fsg) {
+			do_set_interface(common, fsg);
 			usb_composite_setup_continue(common->cdev);
+		}
+		break;
+
+	case FSG_STATE_DISCONNECT:
+		do_set_interface(common, NULL);
 		break;
 
 	case FSG_STATE_EXIT:
@@ -2989,8 +2999,7 @@ static void fsg_unbind(struct usb_configuration *c, struct usb_function *f)
 
 	DBG(fsg, "unbind\n");
 	if (fsg->common->fsg == fsg) {
-		fsg->common->new_fsg = NULL;
-		raise_exception(fsg->common, FSG_STATE_CONFIG_CHANGE);
+		raise_exception(fsg->common, FSG_STATE_DISCONNECT);
 		/* FIXME: make interruptible or killable somehow? */
 		wait_event(common->fsg_wait, common->fsg != fsg);
 	}
diff --git a/drivers/usb/gadget/function/storage_common.h b/drivers/usb/gadget/function/storage_common.h
index e5e3a2553aaa..12687f7e3de9 100644
--- a/drivers/usb/gadget/function/storage_common.h
+++ b/drivers/usb/gadget/function/storage_common.h
@@ -161,6 +161,7 @@ enum fsg_state {
 	FSG_STATE_ABORT_BULK_OUT,
 	FSG_STATE_PROTOCOL_RESET,
 	FSG_STATE_CONFIG_CHANGE,
+	FSG_STATE_DISCONNECT,
 	FSG_STATE_EXIT,
 	FSG_STATE_TERMINATED
 };
-- 
2.20.1