Following the device's documentation guidance, reading a packet from the
device or writing a packet to it must be atomic. Previously, only
reading device's vacancy (before writing on it) or occupancy (before
reading from it) was locked. Hence, effectively reading the packet or
writing the packet wasn't locked at all. However, reading a packet (and
writing one, to a lesser extent) requires to read 3 different registers
in a specific order, without missing one or else we should reset the
device.
This patch fixes the device's locking mechanism on the FIFO character
device. As the device was using copy_from_user() and copy_to_user(), we
need to replace spinlocks with mutexes.
Signed-off-by: Quentin Deslandes <quentin.deslandes@itdev.co.uk>
Link: https://lore.kernel.org/r/20200121103958.12941-1-quentin.deslandes@itdev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently CONFIG_XIL_AXIS_FIFO=y implicitly depends on
CONFIG_HAS_IOMEM=y; consequently, on architectures without IOMEM we get
the following build error:
ld: drivers/staging/axis-fifo/axis-fifo.o: in function `axis_fifo_probe':
drivers/staging/axis-fifo/axis-fifo.c:809: undefined reference to `devm_ioremap_resource'
Fix the build error by adding the unspecified dependency.
Reported-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Link: https://lore.kernel.org/r/20191211192742.95699-7-brendanhiggins@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some properties were parsed from the device tree and then ignored by the
driver. Some would return an error if absent from the device tree, then
return an error if they were found because they are unsupported by the
driver.
Avoid parsing unused properties and clearly explain in the documentation
the ignored / unsupported properties.
Signed-off-by: Quentin Deslandes <quentin.deslandes@itdev.co.uk>
Link: https://lore.kernel.org/r/20191101214232.16960-2-quentin.deslandes@itdev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.
Also since commit f467c5640c ("kconfig: only write '# CONFIG_FOO
is not set' for visible symbols") the Kconfig behavior is the same
regardless of 'default n' being present or not:
...
One side effect of (and the main motivation for) this change is making
the following two definitions behave exactly the same:
config FOO
bool
config FOO
bool
default n
With this change, neither of these will generate a
'# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
That might make it clearer to people that a bare 'default n' is
redundant.
...
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are a few remaining drivers/staging/*/Makefile files that do not
have SPDX identifiers in them. Add the correct GPL-2.0 identifier to
them to make scanning tools happy.
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are a few remaining drivers/staging/*/Kconfig files that do not
have SPDX identifiers in them. Add the correct GPL-2.0 identifier to
them to make scanning tools happy.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When building without CONFIG_OF, the compiler loses track of the flow
control in axis_fifo_probe(), and thinks that many variables are used
without an initialization even though we actually leave the function
before the first use:
drivers/staging/axis-fifo/axis-fifo.c: In function 'axis_fifo_probe':
drivers/staging/axis-fifo/axis-fifo.c:900:5: error: 'rxd_tdata_width' may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (rxd_tdata_width != 32) {
^
drivers/staging/axis-fifo/axis-fifo.c:907:5: error: 'txd_tdata_width' may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (txd_tdata_width != 32) {
^
drivers/staging/axis-fifo/axis-fifo.c:914:5: error: 'has_tdest' may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (has_tdest) {
^
drivers/staging/axis-fifo/axis-fifo.c:919:5: error: 'has_tid' may be used uninitialized in this function [-Werror=maybe-uninitialized]
When CONFIG_OF is set, this does not happen, and since the driver cannot
work without it, just add that option as a Kconfig dependency.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The line is split up to stay in 80 characters-
Signed-off-by: Cristian Sicilia <sicilia.cristian@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
staging: axis-fifo: remove parentheses in axis-fifo.c
Remove parentheses from the end of line and conform to
the coding style guidelines. Reported by checkpatch.
Add an extra space to the function arguments to fix
indentation.
Signed-off-by: Ioannis Valasakis <code@wizofe.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/axis-fifo/axis-fifo.c:1081:3-8: No need to set .owner here. The core will do it.
Remove .owner field if calls are used which set it automatically
Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci
Fixes: 4a965c5f89 ("staging: add driver for Xilinx AXI-Stream FIFO v4.1 IP core")
CC: Jacob Feder <jacobsfeder@gmail.com>
Signed-off-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In case of error, the function device_create() returns ERR_PTR() and
never returns NULL. The NULL test in the return value check should be
replaced with IS_ERR().
Fixes: 4a965c5f89 ("staging: add driver for Xilinx AXI-Stream FIFO v4.1 IP core")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This IP core has read and write AXI-Stream FIFOs, the contents of which can
be accessed from the AXI4 memory-mapped interface. This is useful for
transferring data from a processor into the FPGA fabric. The driver creates
a character device that can be read/written to with standard
open/read/write/close.
See Xilinx PG080 document for IP details.
https://www.xilinx.com/support/documentation/ip_documentation/axi_fifo_mm_s/v4_1/pg080-axi-fifo-mm-s.pdf
The driver currently supports only store-forward mode with a 32-bit
AXI4 Lite interface. DOES NOT support:
- cut-through mode
- AXI4 (non-lite)
Signed-off-by: Jacob Feder <jacobsfeder@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
John B. Wyatt IV