Convert workqueue usage to a real-time kworker. The problem
with workqueues is that we cannot set real-time priorities on
our work and asynchronous reconfiguration can be blocked by
less important tasks.
We need kthread for the interrupt anyway and because we will
now be using single kthread for all TX-related operations we
can get rid of the port mutex.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
LSR_TEMT_BIT (LSR bit 6) provides us exactly the information
we need to determine if transmission is finished - FIFO level
and shift register empty. We can save ourselves reading FIFO
level explicitly if we use this bit.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Without matching bus-specific strings driver will not be loaded
automatically.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Users of RS-485 can request via ioctl that RTS signals should
be activated selected number of milliseconds before the actual
data transmission or delay reception certain number of milli-
seconds after the transmission is finished. In sc16is7xx,
however, RTS signalling is handled by the hardware and driver
has no way of providing this feature.
We still try to provide .delay_rts_before_send by delaying
transmission but without actual effect on the RTS line.
Note: this change will make the driver return -EINVAL when the
feature is requested (.delay_rts_after_send is set).
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
spi interface for sc16is7xx is added along with Kconfig flag
to enable spi or i2c, thus in a instance we can have either
spi or i2c or both, in sync to the hw.
Signed-off-by: Rama Kiran Kumar Indrakanti <indrakanti_ram@hotmail.com>
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Hardware is capable of inverting RTS signal when working
in RS-485 mode. Expose this functionality to user space.
Relay on a matching combination of standard flags
(SER_RS485_RTS_ON_SEND and SER_RS485_RTS_AFTER_SEND) to
detect when user space is requesting inverted RTS mode.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Although clk_disable_unprepare() is called both on .remove()
and in .probe() error path, the clock is never actually enabled.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
EFCR register contains RS-485 configuration which should not
be changed by shutdown. Instead of doing a write only update
the appropriate bits.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If ports are not explicitly removed on the error path
the device will not get properly unregistered leaving
/dev/ttySC* nodes in the filesystem.
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In order to unify all the rs485 ioctl handling.
Use the implementation of TIOC[GS]RS485 ioctl handling on serial_core.
Reviewed-by: Alan Cox <alan@linux.intel.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit e676253b19 ("serial/8250: Add support for RS485 IOCTLs") added
references to TIOC[SG]RS48 on 8250_core.c. This change triggered the
need to define them in all the arches that uses tty/serial.
This made #ifdef TIOC[SG]RS48 obsolete.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We are trying to smoke out the use of the return value from
gpiochip_remove() from the kernel, this has been missed.
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The s->clk never gets setup in sc16is7xx_probe() and instead was using a
local clk variable, but then testing the uninitialized s->clk during
teardown
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This fixes the warnings:
drivers/tty/serial/sc16is7xx.c: In function 'sc16is7xx_handle_rx':
>> drivers/tty/serial/sc16is7xx.c:548:1: warning: 'sc16is7xx_handle_rx' uses dynamic stack allocation [enabled by default]
drivers/tty/serial/sc16is7xx.c: In function 'sc16is7xx_handle_tx':
>> drivers/tty/serial/sc16is7xx.c:589:1: warning: 'sc16is7xx_handle_tx' uses dynamic stack allocation [enabled by default]
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/tty/serial/sc16is7xx.c:1060:12: warning: 'sc16is7xx_probe' defined but not used [-Wunused-function]
static int sc16is7xx_probe(struct device *dev,
^
drivers/tty/serial/sc16is7xx.c:1176:12: warning: 'sc16is7xx_remove' defined but not used [-Wunused-function]
static int sc16is7xx_remove(struct device *dev)
^
drivers/tty/serial/sc16is7xx.c:1215:29: warning: 'regcfg' defined but not used [-Wunused-variable]
static struct regmap_config regcfg = {
^
Fixed these warnings by removing the `#ifdef CONFIG_REGMAP_I2C' around their
calls as this driver selects REGMAP_I2C in Kconfig. This part of driver just
didn't compile at all when REGMAP_I2C configured as module (CONFIG_REGMAP_I2C
is not defined, just CONFIG_REGMAP_I2C_MODULE).
Signed-off-by: Jan Moskyto Matejka <mq@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix by including linux/uaccess.h:
drivers/tty/serial/sc16is7xx.c: In function 'sc16is7xx_ioctl':
>> drivers/tty/serial/sc16is7xx.c:861:3: error: implicit declaration of function 'copy_from_user' [-Werror=implicit-function-declaration]
>> drivers/tty/serial/sc16is7xx.c:867:3: error: implicit declaration of function 'copy_to_user' [-Werror=implicit-function-declaration]
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The SC16IS7xx is a slave I2C-bus/SPI interface to a single-channel
high performance UART. The SC16IS7xx's internal register set is
backward-compatible with the widely used and widely popular 16C450.
The SC16IS7xx also provides additional advanced features such as
auto hardware and software flow control, automatic RS-485 support, and
software reset.
Signed-off-by: Jon Ringle <jringle@gridpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
