Fix CDC ACM error recovery in Raspberry Pi kernels as well (#940)

buildroot-external/board/raspberrypi/patches/linux/0001-brcmfmac-add-FT-based-AKMs-in-brcmf_set_key_mgmt-for.patch

@@ -1,9 +1,9 @@
 From d6fc5f89ac905cb3efc9c61ce79dbfad5d91883b Mon Sep 17 00:00:00 2001
-Message-Id: <d6fc5f89ac905cb3efc9c61ce79dbfad5d91883b.1597690408.git.stefan@agner.ch>
+Message-Id: <d6fc5f89ac905cb3efc9c61ce79dbfad5d91883b.1604607313.git.stefan@agner.ch>
 From: Chung-Hsien Hsu <stanley.hsu@cypress.com>
 Date: Wed, 15 Aug 2018 05:32:39 -0500
-Subject: [PATCH] brcmfmac: add FT-based AKMs in brcmf_set_key_mgmt() for FT
- support
+Subject: [PATCH 1/3] brcmfmac: add FT-based AKMs in brcmf_set_key_mgmt() for
+ FT support
 
 Add WLAN_AKM_SUITE_FT_8021X and WLAN_AKM_SUITE_FT_PSK in
 brcmf_set_key_mgmt() for FT support.
@@ -46,5 +46,5 @@ index 75b2a0438cfa..dddebaa60352 100644
 
  #define DOT11_DEFAULT_RTS_LEN		2347
 -- 
-2.28.0
+2.29.1
 

buildroot-external/board/raspberrypi/patches/linux/0002-CDC-ACM-heed-quirk-also-in-error-handling.patch

@@ -0,0 +1,39 @@
+From 1eaf50e14dfdda654e6acb2a1ee4c18cff346064 Mon Sep 17 00:00:00 2001
+Message-Id: <1eaf50e14dfdda654e6acb2a1ee4c18cff346064.1604607313.git.stefan@agner.ch>
+In-Reply-To: <d6fc5f89ac905cb3efc9c61ce79dbfad5d91883b.1604607313.git.stefan@agner.ch>
+References: <d6fc5f89ac905cb3efc9c61ce79dbfad5d91883b.1604607313.git.stefan@agner.ch>
+From: Oliver Neukum <oneukum@suse.com>
+Date: Tue, 26 May 2020 14:44:20 +0200
+Subject: [PATCH 2/3] CDC-ACM: heed quirk also in error handling
+
+commit 97fe809934dd2b0b37dfef3a2fc70417f485d7af upstream.
+
+If buffers are iterated over in the error case, the lower limits
+for quirky devices must be heeded.
+
+Signed-off-by: Oliver Neukum <oneukum@suse.com>
+Reported-by: Jean Rene Dawin <jdawin@math.uni-bielefeld.de>
+Fixes: a4e7279cd1d19 ("cdc-acm: introduce a cool down")
+Cc: stable <stable@vger.kernel.org>
+Link: https://lore.kernel.org/r/20200526124420.22160-1-oneukum@suse.com
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/usb/class/cdc-acm.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
+index 10ba1b4f0dbf..e8b9b27937ed 100644
+--- a/drivers/usb/class/cdc-acm.c
++++ b/drivers/usb/class/cdc-acm.c
+@@ -590,7 +590,7 @@ static void acm_softint(struct work_struct *work)
+ 	}
+
+ 	if (test_and_clear_bit(ACM_ERROR_DELAY, &acm->flags)) {
+-		for (i = 0; i < ACM_NR; i++)
++		for (i = 0; i < acm->rx_buflimit; i++)
+ 			if (test_and_clear_bit(i, &acm->urbs_in_error_delay))
+ 					acm_submit_read_urb(acm, i, GFP_NOIO);
+ 	}
+-- 
+2.29.1
+

buildroot-external/board/raspberrypi/patches/linux/0003-usb-cdc-acm-fix-cooldown-mechanism.patch

@@ -0,0 +1,130 @@
+From 930c59eeae2bdd02fa1327a69e4df70105f672e4 Mon Sep 17 00:00:00 2001
+Message-Id: <930c59eeae2bdd02fa1327a69e4df70105f672e4.1604607313.git.stefan@agner.ch>
+In-Reply-To: <d6fc5f89ac905cb3efc9c61ce79dbfad5d91883b.1604607313.git.stefan@agner.ch>
+References: <d6fc5f89ac905cb3efc9c61ce79dbfad5d91883b.1604607313.git.stefan@agner.ch>
+From: Jerome Brunet <jbrunet@baylibre.com>
+Date: Mon, 19 Oct 2020 19:07:02 +0200
+Subject: [PATCH 3/3] usb: cdc-acm: fix cooldown mechanism
+
+Commit a4e7279cd1d1 ("cdc-acm: introduce a cool down") is causing
+regression if there is some USB error, such as -EPROTO.
+
+This has been reported on some samples of the Odroid-N2 using the Combee II
+Zibgee USB dongle.
+
+> struct acm *acm = container_of(work, struct acm, work)
+
+is incorrect in case of a delayed work and causes warnings, usually from
+the workqueue:
+
+> WARNING: CPU: 0 PID: 0 at kernel/workqueue.c:1474 __queue_work+0x480/0x528.
+
+When this happens, USB eventually stops working completely after a while.
+Also the ACM_ERROR_DELAY bit is never set, so the cooldown mechanism
+previously introduced cannot be triggered and acm_submit_read_urb() is
+never called.
+
+This changes makes the cdc-acm driver use a single delayed work, fixing the
+pointer arithmetic in acm_softint() and set the ACM_ERROR_DELAY when the
+cooldown mechanism appear to be needed.
+
+Fixes: a4e7279cd1d1 ("cdc-acm: introduce a cool down")
+Cc: Oliver Neukum <oneukum@suse.com>
+Reported-by: Pascal Vizeli <pascal.vizeli@nabucasa.com>
+Acked-by: Oliver Neukum <oneukum@suse.com>
+Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
+Link: https://lore.kernel.org/r/20201019170702.150534-1-jbrunet@baylibre.com
+Cc: stable <stable@vger.kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/usb/class/cdc-acm.c | 12 +++++-------
+ drivers/usb/class/cdc-acm.h |  3 +--
+ 2 files changed, 6 insertions(+), 9 deletions(-)
+
+diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
+index e8b9b27937ed..4b543aa0030d 100644
+--- a/drivers/usb/class/cdc-acm.c
++++ b/drivers/usb/class/cdc-acm.c
+@@ -510,6 +510,7 @@ static void acm_read_bulk_callback(struct urb *urb)
+ 			"%s - cooling babbling device\n", __func__);
+ 		usb_mark_last_busy(acm->dev);
+ 		set_bit(rb->index, &acm->urbs_in_error_delay);
++		set_bit(ACM_ERROR_DELAY, &acm->flags);
+ 		cooldown = true;
+ 		break;
+ 	default:
+@@ -535,7 +536,7 @@ static void acm_read_bulk_callback(struct urb *urb)
+
+ 	if (stopped || stalled || cooldown) {
+ 		if (stalled)
+-			schedule_work(&acm->work);
++			schedule_delayed_work(&acm->dwork, 0);
+ 		else if (cooldown)
+ 			schedule_delayed_work(&acm->dwork, HZ / 2);
+ 		return;
+@@ -570,13 +571,13 @@ static void acm_write_bulk(struct urb *urb)
+ 	acm_write_done(acm, wb);
+ 	spin_unlock_irqrestore(&acm->write_lock, flags);
+ 	set_bit(EVENT_TTY_WAKEUP, &acm->flags);
+-	schedule_work(&acm->work);
++	schedule_delayed_work(&acm->dwork, 0);
+ }
+
+ static void acm_softint(struct work_struct *work)
+ {
+ 	int i;
+-	struct acm *acm = container_of(work, struct acm, work);
++	struct acm *acm = container_of(work, struct acm, dwork.work);
+
+ 	if (test_bit(EVENT_RX_STALL, &acm->flags)) {
+ 		smp_mb(); /* against acm_suspend() */
+@@ -592,7 +593,7 @@ static void acm_softint(struct work_struct *work)
+ 	if (test_and_clear_bit(ACM_ERROR_DELAY, &acm->flags)) {
+ 		for (i = 0; i < acm->rx_buflimit; i++)
+ 			if (test_and_clear_bit(i, &acm->urbs_in_error_delay))
+-					acm_submit_read_urb(acm, i, GFP_NOIO);
++				acm_submit_read_urb(acm, i, GFP_KERNEL);
+ 	}
+
+ 	if (test_and_clear_bit(EVENT_TTY_WAKEUP, &acm->flags))
+@@ -1386,7 +1387,6 @@ static int acm_probe(struct usb_interface *intf,
+ 	acm->ctrlsize = ctrlsize;
+ 	acm->readsize = readsize;
+ 	acm->rx_buflimit = num_rx_buf;
+-	INIT_WORK(&acm->work, acm_softint);
+ 	INIT_DELAYED_WORK(&acm->dwork, acm_softint);
+ 	init_waitqueue_head(&acm->wioctl);
+ 	spin_lock_init(&acm->write_lock);
+@@ -1596,7 +1596,6 @@ static void acm_disconnect(struct usb_interface *intf)
+ 	}
+
+ 	acm_kill_urbs(acm);
+-	cancel_work_sync(&acm->work);
+ 	cancel_delayed_work_sync(&acm->dwork);
+
+ 	tty_unregister_device(acm_tty_driver, acm->minor);
+@@ -1639,7 +1638,6 @@ static int acm_suspend(struct usb_interface *intf, pm_message_t message)
+ 		return 0;
+
+ 	acm_kill_urbs(acm);
+-	cancel_work_sync(&acm->work);
+ 	cancel_delayed_work_sync(&acm->dwork);
+ 	acm->urbs_in_error_delay = 0;
+
+diff --git a/drivers/usb/class/cdc-acm.h b/drivers/usb/class/cdc-acm.h
+index 30380d28a504..d8f8651425c4 100644
+--- a/drivers/usb/class/cdc-acm.h
++++ b/drivers/usb/class/cdc-acm.h
+@@ -111,8 +111,7 @@ struct acm {
+ #		define ACM_ERROR_DELAY	3
+ 	unsigned long urbs_in_error_delay;		/* these need to be restarted after a delay */
+ 	struct usb_cdc_line_coding line;		/* bits, stop, parity */
+-	struct work_struct work;			/* work queue entry for various purposes*/
+-	struct delayed_work dwork;			/* for cool downs needed in error recovery */
++	struct delayed_work dwork;		        /* work queue entry for various purposes */
+ 	unsigned int ctrlin;				/* input control lines (DCD, DSR, RI, break, overruns) */
+ 	unsigned int ctrlout;				/* output control lines (DTR, RTS) */
+ 	struct async_icount iocount;			/* counters for control line changes */
+-- 
+2.29.1
+