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2018-05-24serial: samsung: check DMA engine capabilities before using DMA modeMarek Szyprowski1-4/+29
DMA engine driver might not always provide all the features needed by serial driver to properly operate in DMA mode, so check that before selecting DMA mode. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14serial: samsung: fix maxburst parameter for DMA transactionsMarek Szyprowski1-5/+2
The best granularity of residue that DMA engine can report is in the BURST units, so the serial driver must use MAXBURST = 1 and DMA_SLAVE_BUSWIDTH_1_BYTE if it relies on exact number of bytes transferred by DMA engine. Fixes: 62c37eedb74c ("serial: samsung: add dma reqest/release functions") Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Krzysztof Kozlowski <krzk@kernel.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28serial: samsung: Fix out-of-bounds access through serial port indexGeert Uytterhoeven1-0/+4
The s3c24xx_serial_ports[] array is indexed using a value derived from the "serialN" alias in DT, or from an incrementing probe index, which may lead to an out-of-bounds access. Fix this by adding a range check. Note that the array size is defined by a Kconfig symbol (CONFIG_SERIAL_SAMSUNG_UARTS), so this can even be triggered using a legitimate DTB or legitimate board code. Fixes: 13a9f6c64fdc55eb ("serial: samsung: Consider DT alias when probing ports") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08tty: serial: Remove redundant license textGreg Kroah-Hartman1-4/+0
Now that the SPDX tag is in all tty files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Cc: Jiri Slaby <jslaby@suse.com> Cc: Eric Anholt <eric@anholt.net> Cc: Stefan Wahren <stefan.wahren@i2se.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ray Jui <rjui@broadcom.com> Cc: Scott Branden <sbranden@broadcom.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Joachim Eastwood <manabian@gmail.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: Pat Gefre <pfg@sgi.com> Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Sylvain Lemieux <slemieux.tyco@gmail.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Andy Gross <andy.gross@linaro.org> Cc: David Brown <david.brown@linaro.org> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Barry Song <baohua@kernel.org> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Peter Korsgaard <jacmet@sunsite.dk> Cc: Timur Tabi <timur@tabi.org> Cc: Tony Prisk <linux@prisktech.co.nz> Cc: Michal Simek <michal.simek@xilinx.com> Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08tty: add SPDX identifiers to all remaining files in drivers/tty/Greg Kroah-Hartman1-0/+1
It's good to have SPDX identifiers in all files to make it easier to audit the kernel tree for correct licenses. Update the drivers/tty files files with the correct SPDX license identifier based on the license text in the file itself. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This work is based on a script and data from Thomas Gleixner, Philippe Ombredanne, and Kate Stewart. Cc: Jiri Slaby <jslaby@suse.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: David Sterba <dsterba@suse.com> Cc: James Hogan <jhogan@kernel.org> Cc: Rob Herring <robh@kernel.org> Cc: Eric Anholt <eric@anholt.net> Cc: Stefan Wahren <stefan.wahren@i2se.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ray Jui <rjui@broadcom.com> Cc: Scott Branden <sbranden@broadcom.com> Cc: bcm-kernel-feedback-list@broadcom.com Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Helge Deller <deller@gmx.de> Cc: Joachim Eastwood <manabian@gmail.com> Cc: Matthias Brugger <matthias.bgg@gmail.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Tobias Klauser <tklauser@distanz.ch> Cc: Russell King <linux@armlinux.org.uk> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Richard Genoud <richard.genoud@gmail.com> Cc: Alexander Shiyan <shc_work@mail.ru> Cc: Baruch Siach <baruch@tkos.co.il> Cc: "Maciej W. Rozycki" <macro@linux-mips.org> Cc: "Uwe Kleine-König" <kernel@pengutronix.de> Cc: Pat Gefre <pfg@sgi.com> Cc: "Guilherme G. Piccoli" <gpiccoli@linux.vnet.ibm.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Vladimir Zapolskiy <vz@mleia.com> Cc: Sylvain Lemieux <slemieux.tyco@gmail.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Liviu Dudau <liviu.dudau@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Andy Gross <andy.gross@linaro.org> Cc: David Brown <david.brown@linaro.org> Cc: "Andreas Färber" <afaerber@suse.de> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Laxman Dewangan <ldewangan@nvidia.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Cc: Barry Song <baohua@kernel.org> Cc: Patrice Chotard <patrice.chotard@st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Peter Korsgaard <jacmet@sunsite.dk> Cc: Timur Tabi <timur@tabi.org> Cc: Tony Prisk <linux@prisktech.co.nz> Cc: Michal Simek <michal.simek@xilinx.com> Cc: "Sören Brinkmann" <soren.brinkmann@xilinx.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Jiri Slaby <jslaby@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08serial: samsung: Remove useless spinlockMarek Szyprowski1-4/+0
Spinlock taken only for dma_map_single() for TX buffer is completely useless and doesn't protect anything, so remove it to simplify the code. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08serial: samsung: Add missing checks for dma_map_single failureMarek Szyprowski1-7/+24
This patch adds missing checks for dma_map_single() failure and proper error reporting. Although this issue was harmless on ARM architecture, it is always good to use the DMA mapping API in a proper way. This patch fixes the following DMA API debug warning: WARNING: CPU: 1 PID: 3785 at lib/dma-debug.c:1171 check_unmap+0x8a0/0xf28 dma-pl330 121a0000.pdma: DMA-API: device driver failed to check map error[device address=0x000000006e0f9000] [size=4096 bytes] [mapped as single] Modules linked in: CPU: 1 PID: 3785 Comm: (agetty) Tainted: G W 4.11.0-rc1-00137-g07ca963-dirty #59 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [<c011aaa4>] (unwind_backtrace) from [<c01127c0>] (show_stack+0x20/0x24) [<c01127c0>] (show_stack) from [<c06ba5d8>] (dump_stack+0x84/0xa0) [<c06ba5d8>] (dump_stack) from [<c0139528>] (__warn+0x14c/0x180) [<c0139528>] (__warn) from [<c01395a4>] (warn_slowpath_fmt+0x48/0x50) [<c01395a4>] (warn_slowpath_fmt) from [<c072a114>] (check_unmap+0x8a0/0xf28) [<c072a114>] (check_unmap) from [<c072a834>] (debug_dma_unmap_page+0x98/0xc8) [<c072a834>] (debug_dma_unmap_page) from [<c0803874>] (s3c24xx_serial_shutdown+0x314/0x52c) [<c0803874>] (s3c24xx_serial_shutdown) from [<c07f5124>] (uart_port_shutdown+0x54/0x88) [<c07f5124>] (uart_port_shutdown) from [<c07f522c>] (uart_shutdown+0xd4/0x110) [<c07f522c>] (uart_shutdown) from [<c07f6a8c>] (uart_hangup+0x9c/0x208) [<c07f6a8c>] (uart_hangup) from [<c07c426c>] (__tty_hangup+0x49c/0x634) [<c07c426c>] (__tty_hangup) from [<c07c78ac>] (tty_ioctl+0xc88/0x16e4) [<c07c78ac>] (tty_ioctl) from [<c03b5f2c>] (do_vfs_ioctl+0xc4/0xd10) [<c03b5f2c>] (do_vfs_ioctl) from [<c03b6bf4>] (SyS_ioctl+0x7c/0x8c) [<c03b6bf4>] (SyS_ioctl) from [<c010b4a0>] (ret_fast_syscall+0x0/0x3c) Reported-by: Seung-Woo Kim <sw0312.kim@samsung.com> Fixes: 62c37eedb74c8 ("serial: samsung: add dma reqest/release functions") CC: stable@vger.kernel.org # v4.10+ Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Reviewed-by: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08serial: samsung: Use right device for DMA-mapping callsMarek Szyprowski1-5/+4
Driver should provide its own struct device for all DMA-mapping calls instead of extracting device pointer from DMA engine channel. Although this is harmless from the driver operation perspective on ARM architecture, it is always good to use the DMA mapping API in a proper way. This patch fixes following DMA API debug warning: WARNING: CPU: 0 PID: 0 at lib/dma-debug.c:1241 check_sync+0x520/0x9f4 samsung-uart 12c20000.serial: DMA-API: device driver tries to sync DMA memory it has not allocated [device address=0x000000006df0f580] [size=64 bytes] Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.11.0-rc1-00137-g07ca963 #51 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [<c011aaa4>] (unwind_backtrace) from [<c01127c0>] (show_stack+0x20/0x24) [<c01127c0>] (show_stack) from [<c06ba5d8>] (dump_stack+0x84/0xa0) [<c06ba5d8>] (dump_stack) from [<c0139528>] (__warn+0x14c/0x180) [<c0139528>] (__warn) from [<c01395a4>] (warn_slowpath_fmt+0x48/0x50) [<c01395a4>] (warn_slowpath_fmt) from [<c0729058>] (check_sync+0x520/0x9f4) [<c0729058>] (check_sync) from [<c072967c>] (debug_dma_sync_single_for_device+0x88/0xc8) [<c072967c>] (debug_dma_sync_single_for_device) from [<c0803c10>] (s3c24xx_serial_start_tx_dma+0x100/0x2f8) [<c0803c10>] (s3c24xx_serial_start_tx_dma) from [<c0804338>] (s3c24xx_serial_tx_chars+0x198/0x33c) Reported-by: Seung-Woo Kim <sw0312.kim@samsung.com> Fixes: 62c37eedb74c8 ("serial: samsung: add dma reqest/release functions") CC: stable@vger.kernel.org # v4.0+ Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Reviewed-by: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-07serial: samsung: Continue to work if DMA request failsKrzysztof Kozlowski1-2/+4
If DMA is not available (even when configured in DeviceTree), the driver will fail the startup procedure thus making serial console not available. For example this causes boot failure on QEMU ARMv7 (Exynos4210, SMDKC210): [    1.302575] OF: amba_device_add() failed (-19) for /amba/pdma@12680000 ... [   11.435732] samsung-uart 13800000.serial: DMA request failed [   72.963893] samsung-uart 13800000.serial: DMA request failed [   73.143361] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000000 DMA is not necessary for serial to work, so continue with UART startup after emitting a warning. Fixes: 62c37eedb74c ("serial: samsung: add dma reqest/release functions") Cc: <stable@vger.kernel.org> Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-03serial: samsung: enable clock before accessing interrupt mask resister남영민1-0/+3
Ensure that the uart clock is enabled prior to writing to the interrupt mask register in s3c24xx_serial_resume_noirq function. Without enabing the uart clock, the uart register cannot be accessed. Signed-off-by: Youngmin Nam <youngmin.nam@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-12serial: samsung: Simplify DMA engine initialization codeMarek Szyprowski1-11/+6
dma_request_slave_channel_compat() requires filter function and mask, which are not needed on device tree based platforms, so simplify the code by calling the more appropriate dma_request_chan() function. This additionally gives us proper error handling, because the new function returns error codes instead of NULL on failure. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31serial: samsung: Register cpufreq notifier only on S3C24xxKrzysztof Kozlowski1-1/+1
The Samsung serial driver registered for CPU frequency transitions to recalculate its clock when ARM clock frequency changes. This is needed only on S3C24xx platform so limit the ifdef to respective cpufreq driver. On S3C24xx the ratio ratio between frequencies of UART's parent clock (pclk) and ARM's parent clock (fclk) remains fixed. Therefore when ARM clock frequency goes down, the serial is also affected. Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25tty: serial: samsung: add byte-order aware bit functionsMatthew Leach1-9/+7
This driver makes use of the __set_bit() and __clear_bit() functions. When running under big-endian, these functions don't convert the bit indexes when working with peripheral registers, leading to the incorrect bits being set and cleared when running big-endian. Add two new driver functions for setting and clearing bits that are byte-order aware. Signed-off-by: Matthew Leach <matthew@mattleach.net> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25serial: samsung: Fix possible out of bounds access on non-DT platformKrzysztof Kozlowski1-2/+2
On non-DeviceTree platforms, the index of serial device is a static variable incremented on each probe. It is incremented even if deferred probe happens when getting the clock in s3c24xx_serial_init_port(). This index is used for referencing elements of statically allocated s3c24xx_serial_ports array. In case of re-probe, the index will point outside of this array leading to memory corruption. Increment the index only on successful probe. Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Fixes: b497549a035c ("[ARM] S3C24XX: Split serial driver into core and per-cpu drivers") Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25serial: samsung: Fix ERR pointer dereference on deferred probeKrzysztof Kozlowski1-5/+13
When the clk_get() of "uart" clock returns EPROBE_DEFER, the next re-probe finishes with success but uses invalid (ERR_PTR) values. This leads to dereferencing of ERR_PTR stored under ourport->clk: 12c30000.serial: Controller clock not found (...) 12c30000.serial: ttySAC3 at MMIO 0x12c30000 (irq = 61, base_baud = 0) is a S3C6400/10 Unable to handle kernel paging request at virtual address fffffdfb (clk_prepare) from [<c039f7d0>] (s3c24xx_serial_pm+0x20/0x128) (s3c24xx_serial_pm) from [<c0395414>] (uart_change_pm+0x38/0x40) (uart_change_pm) from [<c039689c>] (uart_add_one_port+0x31c/0x44c) (uart_add_one_port) from [<c03a035c>] (s3c24xx_serial_probe+0x2a8/0x418) (s3c24xx_serial_probe) from [<c03ee110>] (platform_drv_probe+0x50/0xb0) (platform_drv_probe) from [<c03ecb44>] (driver_probe_device+0x1f4/0x2b0) (driver_probe_device) from [<c03eb0c0>] (bus_for_each_drv+0x44/0x8c) (bus_for_each_drv) from [<c03ec8c8>] (__device_attach+0x9c/0x100) (__device_attach) from [<c03ebf54>] (bus_probe_device+0x84/0x8c) (bus_probe_device) from [<c03ec388>] (deferred_probe_work_func+0x60/0x8c) (deferred_probe_work_func) from [<c012fee4>] (process_one_work+0x120/0x328) (process_one_work) from [<c0130150>] (worker_thread+0x2c/0x4ac) (worker_thread) from [<c0135320>] (kthread+0xd8/0xf4) (kthread) from [<c0107978>] (ret_from_fork+0x14/0x3c) The first unsuccessful clk_get() causes s3c24xx_serial_init_port() to exit with failure but the s3c24xx_uart_port is left half-configured (e.g. port->mapbase is set, clk contains ERR_PTR). On next re-probe, the function s3c24xx_serial_init_port() will exit early with success because of configured port->mapbase and driver will use old values, including the ERR_PTR as clock. Fix this by cleaning the port->mapbase on error path so each re-probe will initialize all of the port settings. Fixes: 60e93575476f ("serial: samsung: enable clock before clearing pending interrupts during init") Cc: <stable@vger.kernel.org> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Tested-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30serial: samsung: Reorder the sequence of clock control when call ↵Chanwoo Choi1-2/+2
s3c24xx_serial_set_termios() This patch fixes the broken serial log when changing the clock source of uart device. Before disabling the original clock source, this patch enables the new clock source to protect the clock off state for a split second. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-07serial: samsung: optimize UART rx fifo access routineYoungmin Nam1-5/+13
This patch optimizes UART rx fifo access routine by reading UART SFR when necessary. At first, the "fifocnt" variable will be initialized as Rx FIFO count. So we don't need to access UFSTAT(FIFO status) register every time to check FIFO count because we know that count with "fifocnt". After all data were read out from Rx FIFO, the "fifocnt" will be set as 0. Lastly, UFSTAT will be accessed again to check whether the data remains by any chance. Signed-off-by: Youngmin Nam <ym0914@gmail.com> Reviewed-by: Jung-Ick Guack <ji.guack@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-06earlycon: Use common framework for earlycon declarationsPeter Hurley1-6/+0
Use a single common table of struct earlycon_id for both command line and devicetree. Re-define OF_EARLYCON_DECLARE() macro to instance a unique earlycon declaration (the declaration is only guaranteed to be unique within a compilation unit; separate compilation units must still use unique earlycon names). The semantics of OF_EARLYCON_DECLARE() is different; it declares an earlycon which can matched either on the command line or by devicetree. EARLYCON_DECLARE() is semantically unchanged; it declares an earlycon which is matched by command line only. Remove redundant instances of EARLYCON_DECLARE(). This enables all earlycons to properly initialize struct console with the appropriate name and index, which improves diagnostics and enables direct earlycon-to-console handoff. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04serial: samsung: Fix UART status handling in DMA modeRobert Baldyga1-27/+3
So far, when interrupt occured in DMA mode, it was handled by terminating DMA transfer and draining data remaining in RX FIFO. It worked well until interrupt was caused by timeout, but the same interrupt can be alse caused by special condition (eg. 'break'), which requires special handling. In such case handling mechanism was the same - DMA transaction was terminated and FIFO was drained, but any special conditions were ingnored. Because of this in DMA mode there was no ability to use, for example, Magic SysRq. This patch fixes this problem by using s3c24xx_serial_rx_drain_fifo() function instead of uart_rx_drain_fifo(), which does the same thing (drains RX FIFO) plus checks UART status to detect special conditions (such as 'break'). Thanks to this we have exactly the same UART status handling in both DMA and PIO mode. This change additionally simplifies RX handling code, as we no longer need uart_rx_drain_fifo() function, so we can remove it. Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04serial: samsung: introduce s3c24xx_serial_rx_drain_fifo() functionRobert Baldyga1-10/+13
This patch introduces s3c24xx_serial_rx_drain_fifo() which reads data from RX FIFO and writes it to tty buffer. It also checks for special conditions (such as 'break') and handles it. This function has been separated from s3c24xx_serial_rx_chars_pio() as it contains code which can be used also in DMA mode. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04serial: samsung: remove unneded 'ignore_char' labelRobert Baldyga1-5/+2
This label does nothing special and we don't need to have it anymore. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04serial: samsung: remove unused 'irq' parameterRobert Baldyga1-4/+4
This parameter is not used anywhere, so we can get rid of it. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-04serial: samsung: fix DMA for FIFO smaller than cache line sizeRobert Baldyga1-15/+21
So far DMA mode were activated when only number of bytes to send was equal or greater than min_dma_size. Due to requirement that DMA transaction buffer should be aligned to cache line size, the excessive bytes were written to FIFO before starting DMA transaction. The problem occurred when FIFO size were smaller than cache alignment, because writing all excessive bytes to FIFO would fail. It happened in DMA mode when PIO interrupts disabled, which caused driver hung. The solution is to test if buffer is alligned to cache line size before activating DMA mode, and if it's not, running PIO mode to align buffer and then starting DMA transaction. In PIO mode, when interrupts are enabled, lack of space in FIFO isn't the problem, so buffer aligning will always finish with success. Cc: <stable@vger.kernel.org> # v3.18+ Reported-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-08-04serial: samsung: fix DMA mode enter condition for small FIFO sizesMarek Szyprowski1-2/+11
Due to some of serial ports can have FIFO size smaller than cache line size, and because of need to align DMA buffer address to cache line size, it's necessary to calculate minimum number of bytes for which we want to start DMA transaction to be at least cache line size. The simplest way to meet this requirement is to get maximum of cache line size and FIFO size. Cc: <stable@vger.kernel.org> # v3.18+ Reported-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-07-23serial: samsung: Remove redundant DEBUG_LL checkJavier Martinez Canillas1-1/+0
Commit 84f57d9e3685 ("tty: serial/samsung: fix modular build") fixed build issues when the driver was built as a module. One of those was that printascii is only accessible when the driver is built-in. But there is no need to check for defined(CONFIG_DEBUG_LL) since the SERIAL_SAMSUNG_DEBUG Kconfig symbol already depends on DEBUG_LL. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Acked-by: Kukjin Kim <kgene@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10serial: samsung: Constify platform_device_idKrzysztof Kozlowski1-1/+1
The platform_device_id is not modified by the driver and core uses it as const. Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10serial: samsung: Staticize local symbolKrzysztof Kozlowski1-1/+1
Staticize symbols not exported and not used outside of file. Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-04-28serial: samsung: fix serial console breakRobert Baldyga1-2/+3
This patch fixes problems with serial console break. When function s3c64xx_serial_startup() was started while serial console has been working, it caused lose of characters written to TX FIFO. This effect was particularly observable with systemd, which closes serial port every time when it's not currently needed, hence function s3c64xx_serial_startup() is called quite often there. To fix this problem we avoid resetting TX FIFO if port is used as serial console. Example of broken console log: [ 1086.7 Expecting device dev-ttySAC1.device... [ 1086.[ OK ] Reached target Paths. [ 1086.756416] s[ OK ] Reached target Swap. [ 1086.776413] systemd[1]: Reached target Swap. [ 1086.776642] systemd[1]: Starting Root Slice. [ 5.53403[ OK ] Created slice Root Slice. [ 5.548433] systemd[1]: Create[ OK ] Created slice User and Session Slice. [ 5.568414] sys[ OK ] Listening on /dev/initctl Compatibility Named Pipe. [ 5.588388] s[ OK ] Listening on Delayed Shutdown Socket. [ 5.608376] sy[ OK ] Listening on Journal Socket (/dev/log). [ 5.628361] [ OK ] Listening on udev Kernel Socket. [ 5.648357] s[ OK ] Listening on udev Control Socket. [ 5.668353] s[ OK ] Listening on Journal Socket. [ 5.688366] systemd[1]: Listeni[ OK ] Created slice System Slice. [ 5.708393] Mounting Temporary Directory... [ 7139.067436] Starting prepare device daemon... [ 7139.091726] sy Starting Generate environment from /etc/profile.d... [ 5.792867] system Starting Create Static Device Nodes in /dev... [ 7848.718 Mounting Debug File System... [ 7848.7384 Mounting Configuration File System... [ 5.852 Starting Apply Kernel Variables... [ 5.8720 Starting Setup Virtual Console... [ 7848.798 Starting udev Coldplug all Devices... [ 7848.817 Starting Journal Service... [ OK ] Started Journal Service. [ 7848.854222] s[ OK ] Reached target Slices. Starting Remount Root and Kernel File Systems... [ OK ] Mounted Configuration File System. Reported-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26serial: samsung: Clear operation mode on UART shutdownJavier Martinez Canillas1-0/+1
Exynos serial ports operate either in a DMA-based or interrupt-based modes. In DMA-based mode, the UART generates a transfer data request and a Transmission (Tx) interrupt in interrupt-based mode. The Tx IRQ is only unmasked in interrupt-based mode and it was done in s3c24xx_serial_start_tx(). Commit ba019a3e2ad5 ("serial: samsung: remove redundant interrupt enabling") removed the IRQ enable on that function since it is enabled when the mode is set in enable_tx_pio(). The problem is that enable_tx_pio() is only called if the port mode has not been set before but the mode was not cleared on .shutdown(). So if the UART was shutdown and then started up again, the mode set will remain and the Tx IRQ won't be unmasked. This caused a hang on at least Exynos5250, Exynos5420 and Exynos5800 when the system is rebooted or powered off. Fixes: ba019a3e2ad5 ("serial: samsung: remove redundant interrupt enabling") Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: samsung: earlycon support depends on CONFIG_SERIAL_SAMSUNG_CONSOLEMarek Szyprowski1-0/+2
EarlyCon support depends on serial console infrastructure, so the code implementing it should depend on CONFIG_SERIAL_SAMSUNG_CONSOLE. This patch fixes the following build break: CC [M] drivers/tty/serial/samsung.o drivers/tty/serial/samsung.c:2468:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2468:1: error: expected declaration specifiers or ‘...’ before ‘s3c2410_setup_earlycon’ drivers/tty/serial/samsung.c:2487:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2487:1: error: expected declaration specifiers or ‘...’ before ‘s3c2412_setup_earlycon’ drivers/tty/serial/samsung.c:2488:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2488:1: error: expected declaration specifiers or ‘...’ before ‘s3c2440_setup_earlycon’ drivers/tty/serial/samsung.c:2489:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2489:1: error: expected declaration specifiers or ‘...’ before ‘s3c6400_setup_earlycon’ drivers/tty/serial/samsung.c:2506:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2506:1: error: expected declaration specifiers or ‘...’ before ‘s5pv210_setup_earlycon’ drivers/tty/serial/samsung.c:2507:1: error: expected declaration specifiers or ‘...’ before string constant drivers/tty/serial/samsung.c:2507:1: error: expected declaration specifiers or ‘...’ before ‘exynos4210_setup_earlycon’ drivers/tty/serial/samsung.c:2468:1: warning: ‘s3c2410_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2487:1: warning: ‘s3c2412_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2488:1: warning: ‘s3c2440_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2489:1: warning: ‘s3c6400_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2506:1: warning: ‘s5pv210_setup_earlycon’ defined but not used [-Wunused-function] drivers/tty/serial/samsung.c:2507:1: warning: ‘exynos4210_setup_earlycon’ defined but not used [-Wunused-function] make[3]: *** [drivers/tty/serial/samsung.o] Error 1 Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: samsung: remove redundant interrupt enablingRobert Baldyga1-8/+1
Function s3c24xx_serial_start_tx_pio() enables interrupts if needed, so we don't have to (or even we shouldn't) enable them before. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-02-02serial: samsung: Add support for early consoleTomasz Figa1-0/+103
This patch adds support for early console initialized from device tree and kernel command line to all variants of Samsung serial driver. Signed-off-by: Tomasz Figa <t.figa@samsung.com> [mszyprow: added support for command line based initialization, fixed comments, added documentation] Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com> Tested-by: Alim Akhtar <alim.akhtar@samsung.com> Tested-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-19Merge 3.19-rc5 into tty-nextGreg Kroah-Hartman1-20/+36
We want those tty fixes in that release in this branch as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: samsung: add DMA support for RXRobert Baldyga1-3/+230
Add RX DMA transfers support for samsung serial driver. It's enabled when DMA controller for RX channel is specified in device-tree. DMA transactions are started when number of bytes in RX FIFO reaches trigger level, otherwise PIO mode is used. DMA transfer size is always PAGE_SIZE which can cause large latency when smaller data amount is transferred, so we always terminate DMA transaction on RX timeout interrupt. Timeout interval is set to 64 frame times. Based on previous work of Sylwester Nawrocki and Lukasz Czerwinski. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: samsung: add DMA support for TXRobert Baldyga1-16/+222
Add TX DMA transfers support for samsung serial driver. It's enabled when "dmas" property is defined in serial device-tree node, otherwise TX transfers are prerformed using PIO. TX DMA is used for data segments larger than fifosize to reduce number of interrupts during data transmission. For buffers shorter than fifosize PIO mode is selected. Data blocks for DMA transfers are aligned to cache line size to avoid problems with coherency (some areas of TX circ buffer can be used by CPU during DMA transaction, so we have to ensure that our data is always consistent). Based on previous work of Sylwester Nawrocki and Lukasz Czerwinski. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: samsung: add dma reqest/release functionsRobert Baldyga1-0/+101
Add functions requesting and releasing RX and TX DMA channels. This function are called only when "dmas" property in serial device-tree node is defined. Based on previous work of Sylwester Nawrocki and Lukasz Czerwinski. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: samsung: alloc dma stucture in ourportRobert Baldyga1-0/+12
When we have "dmas" property in serial node in device-tree, we do memory alocation for dma structure which will be used in DMA handling code. Based on previous work of Sylwester Nawrocki and Lukasz Czerwinski. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-09serial: samsung: Add the support for Exynos5433 SoCChanwoo Choi1-20/+36
This patch adds new s3c24xx_serial_drv_data structure for Exynos5433 SoC because Exynos5433 has different fifo size from existing Exynos4 SoC. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-serial@vger.kernel.org Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Acked-by: Inki Dae <inki.dae@samsung.com> Acked-by: Geunsik Lim <geunsik.lim@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-12-14Merge tag 'driver-core-3.19-rc1' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core update from Greg KH: "Here's the set of driver core patches for 3.19-rc1. They are dominated by the removal of the .owner field in platform drivers. They touch a lot of files, but they are "simple" changes, just removing a line in a structure. Other than that, a few minor driver core and debugfs changes. There are some ath9k patches coming in through this tree that have been acked by the wireless maintainers as they relied on the debugfs changes. Everything has been in linux-next for a while" * tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits) Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries" fs: debugfs: add forward declaration for struct device type firmware class: Deletion of an unnecessary check before the function call "vunmap" firmware loader: fix hung task warning dump devcoredump: provide a one-way disable function device: Add dev_<level>_once variants ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries ath: use seq_file api for ath9k debugfs files debugfs: add helper function to create device related seq_file drivers/base: cacheinfo: remove noisy error boot message Revert "core: platform: add warning if driver has no owner" drivers: base: support cpu cache information interface to userspace via sysfs drivers: base: add cpu_device_create to support per-cpu devices topology: replace custom attribute macros with standard DEVICE_ATTR* cpumask: factor out show_cpumap into separate helper function driver core: Fix unbalanced device reference in drivers_probe driver core: fix race with userland in device_add() sysfs/kernfs: make read requests on pre-alloc files use the buffer. sysfs/kernfs: allow attributes to request write buffer be pre-allocated. fs: sysfs: return EGBIG on write if offset is larger than file size ...
2014-11-25serial: samsung: use port->fifosize instead of hardcoded valuesRobert Baldyga1-2/+2
Hardcoded FIFO size can cause hardware performance limitation. Using real size value provides better FIFO usage. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-25serial: samsung: prefer to use fifosize from driver dataRobert Baldyga1-5/+4
If we have fifosize set in driver data we prefer to use it instead of default fifosize value (which is always 16). If there is defined fifosize for particular serial we prefer to use it, otherwise we use value from info, which is common for all serials on given platform. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-25serial: samsung: fix style problemsRobert Baldyga1-18/+28
Split lines longer than 80 chars and remove unnecessary whitespaces. Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-25serial: samsung: wait for transfer completion before clock disableRobert Baldyga1-0/+4
This patch adds waiting until transmit buffer and shifter will be empty before clock disabling. Without this fix it's possible to have clock disabled while data was not transmited yet, which causes unproper state of TX line and problems in following data transfers. Cc: <stable@vger.kernel.org> # v2.6.26+ Signed-off-by: Robert Baldyga <r.baldyga@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05serial: samsung: Remove checks for CONFIG_SAMSUNG_CLOCKPaul Bolle1-27/+0
Commit 32726d2d5502 ("ARM: SAMSUNG: Remove legacy clock code") removed the Kconfig symbol SAMSUNG_CLOCK. Remove the last checks for its macro, and the dead code they hide, too. Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-10-20tty: serial: drop owner assignment from platform_driversWolfram Sang1-1/+0
A platform_driver does not need to set an owner, it will be populated by the driver core. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-08-08Merge tag 'soc-for-3.17' of ↵Linus Torvalds1-4/+0
git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc Pull ARM SoC platform changes from Olof Johansson: "This is the bulk of new SoC enablement and other platform changes for 3.17: - Samsung S5PV210 has been converted to DT and multiplatform - Clock drivers and bindings for some of the lower-end i.MX 1/2 platforms - Kirkwood, one of the popular Marvell platforms, is folded into the mvebu platform code, removing mach-kirkwood - Hwmod data for TI AM43xx and DRA7 platforms - More additions of Renesas shmobile platform support - Removal of plat-samsung contents that can be removed with S5PV210 being multiplatform/DT-enabled and the other two old platforms being removed New platforms (most with only basic support right now): - Hisilicon X5HD2 settop box chipset is introduced - Mediatek MT6589 (mobile chipset) is introduced - Broadcom BCM7xxx settop box chipset is introduced + as usual a lot other pieces all over the platform code" * tag 'soc-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (240 commits) ARM: hisi: remove smp from machine descriptor power: reset: move hisilicon reboot code ARM: dts: Add hix5hd2-dkb dts file. ARM: debug: Rename Hi3716 to HIX5HD2 ARM: hisi: enable hix5hd2 SoC ARM: hisi: add ARCH_HISI MAINTAINERS: add entry for Broadcom ARM STB architecture ARM: brcmstb: select GISB arbiter and interrupt drivers ARM: brcmstb: add infrastructure for ARM-based Broadcom STB SoCs ARM: configs: enable SMP in bcm_defconfig ARM: add SMP support for Broadcom mobile SoCs Documentation: arm: misc updates to Marvell EBU SoC status Documentation: arm: add URLs to public datasheets for the Marvell Armada XP SoC ARM: mvebu: fix build without platforms selected ARM: mvebu: add cpuidle support for Armada 38x ARM: mvebu: add cpuidle support for Armada 370 cpuidle: mvebu: add Armada 38x support cpuidle: mvebu: add Armada 370 support cpuidle: mvebu: rename the driver from armada-370-xp to mvebu-v7 ARM: mvebu: export the SCU address ...
2014-07-19serial: samsung: Remove support for legacy clock codeTomasz Figa1-4/+0
All Samsung platforms are now using the Common Clock Framework and the legacy clock code is being removed, so remove related dead code from samsung-serial driver as well. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2014-07-17serial: samsung: improve code clarity by defining a variableNaveen Krishna Chatradhi1-4/+5
The of_node is derived from pdev for every usage, define a device_node variable instead. Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com> Reviewed-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-17serial: samsung: correct the case and default order in switchNaveen Krishna Chatradhi1-1/+1
The cases should comes before default in a switch. Even if we want the case and default to share same code. Its good to define the case first followed by default. Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com> Reviewed-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-17serial: samsung: get fifosize via device treeNaveen Krishna Chatradhi1-3/+9
UART modules on some SoCs only differ in the fifosize of each UART channel. Its useless to duplicate the drv_data structure or create a compatible name for such a change. We can get fifosize via the device tree nodes (not mandating it). Also updates the documentation. Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@samsung.com> Reviewed-by: Tomasz Figa <t.figa@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>