This is a note to let you know that I've just added the patch titled
usb: roles: Add a description for the class to Kconfig
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-next branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will also be merged in the next major kernel release
during the merge window.
If you have any questions about this process, please let me know.
>From c3788cd9963eb2e77de3c24142fb7c67b61f1a26 Mon Sep 17 00:00:00 2001
From: Heikki Krogerus <heikki.krogerus(a)linux.intel.com>
Date: Wed, 12 Dec 2018 20:13:55 +0300
Subject: usb: roles: Add a description for the class to Kconfig
That makes the USB role switch support option visible and
selectable for the user. The class driver is also moved to
drivers/usb/roles/ directory.
This will fix an issue that we have with the Intel USB role
switch driver on systems that don't have USB Type-C connectors:
Intel USB role switch driver depends on the USB role switch
class as it should, but since there was no way for the user
to enable the USB role switch class, there was also no way
to select that driver. USB Type-C drivers select the USB
role switch class which makes the Intel USB role switch
driver available and therefore hides the problem.
So in practice Intel USB role switch driver was depending on
USB Type-C drivers.
Fixes: f6fb9ec02be1 ("usb: roles: Add Intel xHCI USB role switch driver")
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Heikki Krogerus <heikki.krogerus(a)linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/usb/Kconfig | 4 ----
drivers/usb/common/Makefile | 1 -
drivers/usb/roles/Kconfig | 13 +++++++++++++
drivers/usb/roles/Makefile | 4 +++-
drivers/usb/{common/roles.c => roles/class.c} | 0
5 files changed, 16 insertions(+), 6 deletions(-)
rename drivers/usb/{common/roles.c => roles/class.c} (100%)
diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
index 987fc5ba6321..70e6c956c23c 100644
--- a/drivers/usb/Kconfig
+++ b/drivers/usb/Kconfig
@@ -205,8 +205,4 @@ config USB_ULPI_BUS
To compile this driver as a module, choose M here: the module will
be called ulpi.
-config USB_ROLE_SWITCH
- tristate
- select USB_COMMON
-
endif # USB_SUPPORT
diff --git a/drivers/usb/common/Makefile b/drivers/usb/common/Makefile
index fb4d5ef4165c..0a7c45e85481 100644
--- a/drivers/usb/common/Makefile
+++ b/drivers/usb/common/Makefile
@@ -9,4 +9,3 @@ usb-common-$(CONFIG_USB_LED_TRIG) += led.o
obj-$(CONFIG_USB_OTG_FSM) += usb-otg-fsm.o
obj-$(CONFIG_USB_ULPI_BUS) += ulpi.o
-obj-$(CONFIG_USB_ROLE_SWITCH) += roles.o
diff --git a/drivers/usb/roles/Kconfig b/drivers/usb/roles/Kconfig
index f5a5e6f79f1b..e4194ac94510 100644
--- a/drivers/usb/roles/Kconfig
+++ b/drivers/usb/roles/Kconfig
@@ -1,3 +1,16 @@
+config USB_ROLE_SWITCH
+ tristate "USB Role Switch Support"
+ help
+ USB Role Switch is a device that can select the USB role - host or
+ device - for a USB port (connector). In most cases dual-role capable
+ USB controller will also represent the switch, but on some platforms
+ multiplexer/demultiplexer switch is used to route the data lines on
+ the USB connector between separate USB host and device controllers.
+
+ Say Y here if your USB connectors support both device and host roles.
+ To compile the driver as module, choose M here: the module will be
+ called roles.ko.
+
if USB_ROLE_SWITCH
config USB_ROLES_INTEL_XHCI
diff --git a/drivers/usb/roles/Makefile b/drivers/usb/roles/Makefile
index e44b179ba275..c02873206fc1 100644
--- a/drivers/usb/roles/Makefile
+++ b/drivers/usb/roles/Makefile
@@ -1 +1,3 @@
-obj-$(CONFIG_USB_ROLES_INTEL_XHCI) += intel-xhci-usb-role-switch.o
+obj-$(CONFIG_USB_ROLE_SWITCH) += roles.o
+roles-y := class.o
+obj-$(CONFIG_USB_ROLES_INTEL_XHCI) += intel-xhci-usb-role-switch.o
diff --git a/drivers/usb/common/roles.c b/drivers/usb/roles/class.c
similarity index 100%
rename from drivers/usb/common/roles.c
rename to drivers/usb/roles/class.c
--
2.20.1
On 12/14/18 7:55 AM, Ross Lagerwall wrote:
> If pcistub_init_device fails, the release function will be called with
> dev_data set to NULL. Check it before using it to avoid a NULL pointer
> dereference.
>
> Signed-off-by: Ross Lagerwall <ross.lagerwall(a)citrix.com>
I think this should go to stable trees too (copying them)
Applied to for-linus-4.21
-boris
> ---
> drivers/xen/xen-pciback/pci_stub.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
> index 59661db144e5..097410a7cdb7 100644
> --- a/drivers/xen/xen-pciback/pci_stub.c
> +++ b/drivers/xen/xen-pciback/pci_stub.c
> @@ -106,7 +106,8 @@ static void pcistub_device_release(struct kref *kref)
> * is called from "unbind" which takes a device_lock mutex.
> */
> __pci_reset_function_locked(dev);
> - if (pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state))
> + if (dev_data &&
> + pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state))
> dev_info(&dev->dev, "Could not reload PCI state\n");
> else
> pci_restore_state(dev);
This is a note to let you know that I've just added the patch titled
Revert "serial: 8250: Fix clearing FIFOs in RS485 mode again"
to my tty git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git
in the tty-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 3c9dc275dba1124c1e16e7037226038451286813 Mon Sep 17 00:00:00 2001
From: Paul Burton <paul.burton(a)mips.com>
Date: Sun, 16 Dec 2018 20:10:01 +0000
Subject: Revert "serial: 8250: Fix clearing FIFOs in RS485 mode again"
Commit f6aa5beb45be ("serial: 8250: Fix clearing FIFOs in RS485 mode
again") makes a change to FIFO clearing code which its commit message
suggests was intended to be specific to use with RS485 mode, however:
1) The change made does not just affect __do_stop_tx_rs485(), it also
affects other uses of serial8250_clear_fifos() including paths for
starting up, shutting down or auto-configuring a port regardless of
whether it's an RS485 port or not.
2) It makes the assumption that resetting the FIFOs is a no-op when
FIFOs are disabled, and as such it checks for this case & explicitly
avoids setting the FIFO reset bits when the FIFO enable bit is
clear. A reading of the PC16550D manual would suggest that this is
OK since the FIFO should automatically be reset if it is later
enabled, but we support many 16550-compatible devices and have never
required this auto-reset behaviour for at least the whole git era.
Starting to rely on it now seems risky, offers no benefit, and
indeed breaks at least the Ingenic JZ4780's UARTs which reads
garbage when the RX FIFO is enabled if we don't explicitly reset it.
3) By only resetting the FIFOs if they're enabled, the behaviour of
serial8250_do_startup() during boot now depends on what the value of
FCR is before the 8250 driver is probed. This in itself seems
questionable and leaves us with FCR=0 & no FIFO reset if the UART
was used by 8250_early, otherwise it depends upon what the
bootloader left behind.
4) Although the naming of serial8250_clear_fifos() may be unclear, it
is clear that callers of it expect that it will disable FIFOs. Both
serial8250_do_startup() & serial8250_do_shutdown() contain comments
to that effect, and other callers explicitly re-enable the FIFOs
after calling serial8250_clear_fifos(). The premise of that patch
that disabling the FIFOs is incorrect therefore seems wrong.
For these reasons, this reverts commit f6aa5beb45be ("serial: 8250: Fix
clearing FIFOs in RS485 mode again").
Signed-off-by: Paul Burton <paul.burton(a)mips.com>
Fixes: f6aa5beb45be ("serial: 8250: Fix clearing FIFOs in RS485 mode again").
Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
Cc: Daniel Jedrychowski <avistel(a)gmail.com>
Cc: Marek Vasut <marex(a)denx.de>
Cc: linux-mips(a)vger.kernel.org
Cc: linux-serial(a)vger.kernel.org
Cc: stable <stable(a)vger.kernel.org> # 4.10+
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/tty/serial/8250/8250_port.c | 29 +++++------------------------
1 file changed, 5 insertions(+), 24 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index f776b3eafb96..3f779d25ec0c 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -552,30 +552,11 @@ static unsigned int serial_icr_read(struct uart_8250_port *up, int offset)
*/
static void serial8250_clear_fifos(struct uart_8250_port *p)
{
- unsigned char fcr;
- unsigned char clr_mask = UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT;
-
if (p->capabilities & UART_CAP_FIFO) {
- /*
- * Make sure to avoid changing FCR[7:3] and ENABLE_FIFO bits.
- * In case ENABLE_FIFO is not set, there is nothing to flush
- * so just return. Furthermore, on certain implementations of
- * the 8250 core, the FCR[7:3] bits may only be changed under
- * specific conditions and changing them if those conditions
- * are not met can have nasty side effects. One such core is
- * the 8250-omap present in TI AM335x.
- */
- fcr = serial_in(p, UART_FCR);
-
- /* FIFO is not enabled, there's nothing to clear. */
- if (!(fcr & UART_FCR_ENABLE_FIFO))
- return;
-
- fcr |= clr_mask;
- serial_out(p, UART_FCR, fcr);
-
- fcr &= ~clr_mask;
- serial_out(p, UART_FCR, fcr);
+ serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO);
+ serial_out(p, UART_FCR, UART_FCR_ENABLE_FIFO |
+ UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
+ serial_out(p, UART_FCR, 0);
}
}
@@ -1467,7 +1448,7 @@ static void __do_stop_tx_rs485(struct uart_8250_port *p)
* Enable previously disabled RX interrupts.
*/
if (!(p->port.rs485.flags & SER_RS485_RX_DURING_TX)) {
- serial8250_clear_fifos(p);
+ serial8250_clear_and_reinit_fifos(p);
p->ier |= UART_IER_RLSI | UART_IER_RDI;
serial_port_out(&p->port, UART_IER, p->ier);
--
2.20.1