Commit Graph

61 Commits

Author SHA1 Message Date
Lee Jones 216daa1209 tty: serial: serial-tegra: Provide some missing struct member descriptions
Fixes the following W=1 kernel build warning(s):

 drivers/tty/serial/serial-tegra.c:94: warning: Function parameter or member 'fifo_mode_enable_status' not described in 'tegra_uart_chip_data'
 drivers/tty/serial/serial-tegra.c:94: warning: Function parameter or member 'uart_max_port' not described in 'tegra_uart_chip_data'
 drivers/tty/serial/serial-tegra.c:94: warning: Function parameter or member 'max_dma_burst_bytes' not described in 'tegra_uart_chip_data'
 drivers/tty/serial/serial-tegra.c:94: warning: Function parameter or member 'error_tolerance_low_range' not described in 'tegra_uart_chip_data'
 drivers/tty/serial/serial-tegra.c:94: warning: Function parameter or member 'error_tolerance_high_range' not described in 'tegra_uart_chip_data'

Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-tegra@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20201104193549.4026187-31-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-06 10:54:05 +01:00
Lee Jones 0fd872d716 tty: serial: serial-tegra: Struct headers should start with 'struct <name>'
Fixes the following W=1 kernel build warning(s):

 drivers/tty/serial/serial-tegra.c:85: warning: cannot understand function prototype: 'struct tegra_uart_chip_data '

Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-tegra@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20201104193549.4026187-25-lee.jones@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-06 10:54:05 +01:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Greg Kroah-Hartman dbaab9469b Linux 5.8-rc7
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Merge 5.8-rc7 into tty-next

we need the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-27 12:40:56 +02:00
Johan Hovold 707631ce63 serial: tegra: drop bogus NULL tty-port checks
The struct tty_port is part of the uart state and will never be NULL in
the receive helpers. Drop the bogus NULL checks and rename the
pointer-variables "port" to differentiate them from struct tty_struct
pointers (which can be NULL).

Fixes: 962963e4ee ("serial: tegra: Switch to using struct tty_port")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200710135947.2737-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-21 20:59:38 +02:00
Johan Hovold b374c562ee serial: tegra: fix CREAD handling for PIO
Commit 33ae787b74 ("serial: tegra: add support to ignore read") added
support for dropping input in case CREAD isn't set, but for PIO the
ignore_status_mask wasn't checked until after the character had been
put in the receive buffer.

Note that the NULL tty-port test is bogus and will be removed by a
follow-on patch.

Fixes: 33ae787b74 ("serial: tegra: add support to ignore read")
Cc: stable <stable@vger.kernel.org>     # 5.4
Cc: Shardar Shariff Md <smohammed@nvidia.com>
Cc: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200710135947.2737-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-21 20:58:25 +02:00
Randolph Maaßen f1681a9a2a serial: serial-tegra: reduce irq-latency after rx errors
Since dev_err() calls can lead to synchronous writes to another serial
console these calls can provide significant latency during irq-handling
in tegra_uart_isr(). With this latency another interrupt is likely to
apper during handling of the first interrupt, which might lock up the
kernel completely.

These errors are reported to the error counters so converting the
dev_err() to dev_dbg() is appropriate.

Signed-off-by: Randolph Maaßen <gaireg@gaireg.de>
Link: https://lore.kernel.org/r/20200605145714.9964-1-gaireg@gaireg.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-27 16:12:45 +02:00
Dmitry Osipenko 1f69a1273b tty: serial: tegra: Handle RX transfer in PIO mode if DMA wasn't started
It is possible to get an instant RX timeout or end-of-transfer interrupt
before RX DMA was started, if transaction is less than 16 bytes. Transfer
should be handled in PIO mode in this case because DMA can't handle it.
This patch brings back the original behaviour of the driver that was
changed by accident by a previous commit, it fixes occasional Bluetooth HW
initialization failures which I started to notice recently.

Fixes: d5e3fadb70 ("tty: serial: tegra: Activate RX DMA transfer by request")
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20200209164415.9632-1-digetx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-10 12:32:13 -08:00
Dmitry Osipenko 5c116fdf56 tty: serial: tegra: Optimize DMA buffer synchronization
Synchronize only the dirty part of DMA buffer in order to avoid
unnecessary overhead of syncing of the clean part, which is the case
of every serial DMA transfer in practice.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20200112180919.5194-3-digetx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14 14:07:50 +01:00
Dmitry Osipenko d5e3fadb70 tty: serial: tegra: Activate RX DMA transfer by request
This allows DMA engine to go into runtime-suspended mode whenever there is
no data to receive, instead of keeping DMA active all the time while TTY
is opened (i.e. permanently active in practice, like in the case of UART
Bluetooth).

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Link: https://lore.kernel.org/r/20200112180919.5194-2-digetx@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14 14:07:50 +01:00
Peter Ujfalusi 84a25d956c tty: serial: tegra: Use dma_request_chan() directly for channel request
dma_request_slave_channel_reason() is:
#define dma_request_slave_channel_reason(dev, name) \
	dma_request_chan(dev, name)

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20191113094618.1725-4-peter.ujfalusi@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-13 21:54:16 +08:00
Krishna Yarlagadda 1dce2df3ee serial: tegra: Add PIO mode support
Add PIO mode support in receive and transmit path with RX interrupt
trigger of 16 bytes for Tegra194 and older chips.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-13-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:05 +02:00
Krishna Yarlagadda d781ec21ba serial: tegra: report clk rate errors
Standard UART controllers support +/-4% baud rate error tolerance.
Tegra186 only supports 0% to +4% error tolerance whereas other Tegra
chips support standard +/-4% rate. Add chip data for knowing error
tolerance level for each soc. Creating new compatible for Tegra194
chip as it supports baud rate error tolerance of -2 to +2%, different
from older chips.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-12-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:05 +02:00
Krishna Yarlagadda f04a3cc8d4 serial: tegra: add support to adjust baud rate
Add support to adjust baud rates to fall under supported tolerance
range through DT.

Tegra186 chip has a hardware issue resulting in frame errors when
tolerance level for baud rate is negative. Provided entries to adjust
baud rate to be within acceptable range and work with devices that
can send negative baud rate. Also report error when baud rate set is
out of tolerance range of controller updated in device tree.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-11-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:05 +02:00
Krishna Yarlagadda 7799a3aa81 serial: tegra: add support to use 8 bytes trigger
Add support to use 8 bytes trigger for Tegra186 SOC.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-9-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:05 +02:00
Krishna Yarlagadda 53d0a062cb serial: tegra: set maximum num of uart ports to 8
Set maximum number of UART ports to 8 as older chips have 5 ports and
Tergra186 and later chips will have 8 ports. Add this info to chip
data. Read device tree compatible of this driver and register uart
driver with max ports of matching chip data.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-8-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:04 +02:00
Krishna Yarlagadda 222dcdff34 serial: tegra: check for FIFO mode enabled status
Chips prior to Tegra186 needed delay of 3 UART clock cycles to avoid
data loss. This issue is fixed in Tegra186 and a new flag is added to
check if FIFO mode is enabled. chip data updated to check if this flag
is available for a chip. Tegra186 has new compatible to enable this
flag.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-7-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:04 +02:00
Krishna Yarlagadda cb79f504bb serial: tegra: report error to upper tty layer
Report overrun/parity/frame/break errors to top tty layer. Add support
to ignore break character if IGNBRK is set.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-5-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:04 +02:00
Shardar Shariff Md b9c2470fb1 serial: tegra: flush the RX fifo on frame error
FIFO reset/flush code implemented now does not follow programming
guidelines. RTS line has to be turned off while flushing FIFOs to
avoid new transfers. Also check LSR bits UART_LSR_TEMT and UART_LSR_DR
to confirm FIFOs are flushed.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-4-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:03 +02:00
Ahung Cheng 494f79bd23 serial: tegra: avoid reg access when clk disabled
This avoids two race conditions from the UART shutdown sequence both
leading to 'Machine check error in AXI2APB' and kernel oops.

One was that the clock was disabled before the DMA was terminated making
it possible for the DMA callbacks to be called after the clock was
disabled. These callbacks could write to the UART registers causing
timeout.

The second was that the clock was disabled before the UART was
completely flagged as closed. This is done after the shutdown is called
and a new write could be started after the clock was disabled.
tegra_uart_start_pio_tx could be called causing timeout.

Given that the baud rate is reset at the end of shutdown sequence, this
fix is to examine the baud rate to avoid register access from both race
conditions.

Besides, terminate the DMA before disabling the clock.

Signed-off-by: Ahung Cheng <ahcheng@nvidia.com>
Signed-off-by: Shardar Mohammed <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-3-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:03 +02:00
Shardar Shariff Md 33ae787b74 serial: tegra: add support to ignore read
Add support to ignore read characters if CREAD flag is not set.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Link: https://lore.kernel.org/r/1567572187-29820-2-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-05 10:00:03 +02:00
Ahung Cheng 18a4c404d2 serial: tegra: protect IER against LCR.DLAB
The IER and DLH registers occupy the same address space, selected by
the LCR.DLAB bit. Hence, add port lock to protect IER when LCR.DLAB bit
is set.

Signed-off-by: Ahung Cheng <ahcheng@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/1565609303-27000-5-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-04 12:43:54 +02:00
Andreas Abel 6300b140c2 serial: tegra: add internal loopback functionality
Add the internal loopback functionality that can be enabled with
TIOCM_LOOP.

Signed-off-by: Andreas Abel <aabel@nvidia.com>
Signed-off-by: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/1565609303-27000-2-git-send-email-kyarlagadda@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-04 12:43:54 +02:00
Stephen Boyd 1df2178681 tty: Remove dev_err() usage after platform_get_irq()
We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.

// <smpl>
@@
expression ret;
struct platform_device *E;
@@

ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);

if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>

While we're here, remove braces on if statements that only have one
statement (manually).

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20190730181557.90391-45-swboyd@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-04 12:43:49 +02:00
Marcel Ziswiler 3957386aeb serial: tegra: fix some spelling mistakes
Fix a few spelling mistakes I stumbled upon while debugging a customers
UART issues.

Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-09 08:58:18 -08:00
Greg Kroah-Hartman 4793f2ebff tty: serial: Remove redundant license text
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>
2017-11-08 13:08:12 +01:00
Greg Kroah-Hartman e3b3d0f549 tty: add SPDX identifiers to all remaining files in drivers/tty/
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>
2017-11-08 13:08:12 +01:00
Philipp Zabel f67276a0ee serial: tegra: explicitly request exclusive reset control
Commit a53e35db70 ("reset: Ensure drivers are explicit when requesting
reset lines") started to transition the reset control request API calls
to explicitly state whether the driver needs exclusive or shared reset
control behavior. Convert all drivers requesting exclusive resets to the
explicit API call so the temporary transition helpers can be removed.

No functional changes.

Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-tegra@vger.kernel.org
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-30 07:35:28 -07:00
Bhumika Goyal 2331e06865 tty: serial: constify uart_ops structures
Declare uart_ops structures as const as they are only stored in the ops
field of an uart_port structure. This field is of type const, so
uart_ops structures having this property can be made const too.

File size details before and after patching.
First line of every .o file shows the file size before patching
and second line shows the size after patching.

   text	   data	    bss	    dec	    hex	filename

   2977	    456	     64	   3497	    da9	drivers/tty/serial/amba-pl010.o
   3169	    272	     64	   3505	    db1	drivers/tty/serial/amba-pl010.o

   3109	    456	      0	   3565	    ded	drivers/tty/serial/efm32-uart.o
   3301	    272	      0	   3573	    df5	drivers/tty/serial/efm32-uart.o

  10668	    753	      1	  11422	   2c9e	drivers/tty/serial/icom.o
  10860	    561	      1	  11422	   2c9e	drivers/tty/serial/icom.o

  23904	    408	      8	  24320	   5f00	drivers/tty/serial/ioc3_serial.o
  24088	    224	      8	  24320	   5f00	drivers/tty/serial/ioc3_serial.o

  10516	    560	      4	  11080	   2b48	drivers/tty/serial/ioc4_serial.o
  10709	    368	      4	  11081	   2b49	drivers/tty/serial/ioc4_serial.o

   7853	    648	   1216	   9717	   25f5	drivers/tty/serial/mpsc.o
   8037	    456	   1216	   9709	   25ed	drivers/tty/serial/mpsc.o

  10248	    456	      0	  10704	   29d0	drivers/tty/serial/omap-serial.o
  10440	    272	      0	  10712	   29d8	drivers/tty/serial/omap-serial.o

   8122	    532	   1984	  10638	   298e	drivers/tty/serial/pmac_zilog.o
   8306	    340	   1984	  10630	   2986	drivers/tty/serial/pmac_zilog.o

   3808	    456	      0	   4264	   10a8	drivers/tty/serial/pxa.o
   4000	    264	      0	   4264	   10a8	drivers/tty/serial/pxa.o

  21781	   3864	      0	  25645	   642d	drivers/tty/serial/serial-tegra.o
  22037	   3608	      0	  25645	   642d	drivers/tty/serial/serial-tegra.o

   2481	    456	     96	   3033	    bd9	drivers/tty/serial/sprd_serial.o
   2673	    272	     96	   3041	    be1	drivers/tty/serial/sprd_serial.o

   5534	    300	    512	   6346	   18ca	drivers/tty/serial/vr41xx_siu.o
   5630	    204	    512	   6346	   18ca	drivers/tty/serial/vr41xx_siu.o

   6730	   1576	    128	   8434	   20f2	drivers/tty/serial/vt8500_serial.o
   6986	   1320	    128	   8434	   20f2	drivers/tty/serial/vt8500_serial.o

Cross compiled for mips architecture.

   3005	    488	      0	   3493	    da5	drivers/tty/serial/pnx8xxx_uart.o
   3189	    304	      0	   3493	    da5	drivers/tty/serial/pnx8xxx_uart.o

   4272	    196	   1056	   5524	   1594	drivers/tty/serial/dz.o
   4368	    100	   1056	   5524	   1594	drivers/tty/serial/dz.o

   6551	    144	     16	   6711	   1a37	drivers/tty/serial/ip22zilog.o
   6647	     48	     16	   6711	   1a37	drivers/tty/serial/ip22zilog.o

   9612	    428	   1520	  11560	   2d28	drivers/tty/serial/serial_txx9.o
   9708	    332	   1520	  11560	   2d28	drivers/tty/serial/serial_txx9.o

   4156	    296	     16	   4468	   1174	drivers/tty/serial/ar933x_uart.o
   4252	    200	     16	   4468	   1174	drivers/tty/serial/ar933x_uart.o

Cross compiled for arm archiecture.

  11716	   1780	     44	  13540	   34e4	drivers/tty/serial/sirfsoc_uart.o
  11808	   1688	     44	  13540	   34e4	drivers/tty/serial/sirfsoc_uart.o

  13352	    596	     56	  14004	   36b4	drivers/tty/serial/amba-pl011.o
  13444	    504	     56	  14004	   36b4	drivers/tty/serial/amba-pl011.o

Cross compiled for sparc architecture.

   4664	    528	     32	   5224	   1468	drivers/tty/serial/sunhv.o
   4848	    344	     32	   5224	   1468	drivers/tty/serial/sunhv.o

   8080	    332	     28	   8440	   20f8	drivers/tty/serial/sunzilog.o
   8184	    228	     28	   8440	   20f8	drivers/tty/serial/sunzilog.o

Cross compiled for ia64 architecture.

  10226	    549	    472	  11247	   2bef	drivers/tty/serial/sn_console.o
  10414	    365	    472	  11251	   2bf3	drivers/tty/serial/sn_console.o

The files drivers/tty/serial/zs.o, drivers/tty/serial/lpc32xx_hs.o and
drivers/tty/serial/lantiq.o did not compile.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-27 09:23:36 +01:00
Jiri Slaby 394a9e2ca2 TTY: serial, handle platform_get_irq retval properly
platform_get_irq can fail, so we should handle negative value when
returned.

[v2]

platform_get_irq can actually return zero on some platforms. So do not
remove checks for irq == 0 there.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: "Uwe Kleine-König" <kernel@pengutronix.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-tegra@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-25 09:01:52 -07:00
Thierry Reding 06c5e362ce serial: tegra: Remove unused variable
The local mcr variable is never used in the tegra_uart_set_mctrl()
function, so it should be removed.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-30 09:26:55 -07:00
Jon Hunter 32ede4a517 serial: tegra: Add helper function for handling RX buffer
In the tegra UART driver there are three places where the RX DMA buffer
is handled and pushed up to the tty layer. In all three instances the
same functions are called and so instead of duplicating the code in three
places, move this code to a new helper function and use this new function.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:07:57 -07:00
Jon Hunter b0e066ccb5 serial: tegra: Remove redundant code and check in tegra_uart_stop_rx()
The serial-tegra driver always uses DMA and hence the driver always
allocates DMA channels. Therefore, the test to see if the RX DMA channel
is initialised in tegra_uart_stop_rx() is unnecessary and so remove
the test and the code that corresponds to the case where the RX DMA
channel is not initialised. Please note that the call to
tegra_uart_stop_rx() should always be before the call to
tegra_uart_shutdown() which will uninitialise the RX DMA channel.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:07:57 -07:00
Jon Hunter 2230a9475f serial: tegra: Remove unnecessary return statements
Some functions in the serial-tegra driver have unnecessary return
statements at the end of a void function and so remove them.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:07:57 -07:00
Jon Hunter 2a24bb28a3 serial: tegra: Handle another RX race condition
Commit 853a699739 ("serial: tegra: handle race condition on uart rx
side") attempted to fix a race condition between the RX end of
transmission interrupt and RX DMA completion callback. Despite this
fix there is still another case where these two paths can race and
result in duplicated data. The race condition is as follows:

1. DMA completion interrupt occurs and schedules tasklet to call DMA
   callback.
2. DMA callback for the UART driver starts to execute. This will copy
   the data from the DMA buffer and restart the DMA. This is done under
   uart port spinlock.
3. During the callback, UART interrupt is raised for end of receive. The
   UART ISR runs and waits to acquire port spinlock held by the DMA
   callback.
4. DMA callback gives up spinlock after copying the data, but before
   restarting DMA.
5. UART ISR acquires the spin lock and reads the same DMA buffer because
   DMA has not been restarted yet.

The release of the spinlock during the DMA callback was introduced by
commit 9b88748b36 ("tty: serial: tegra: drop uart_port->lock before
calling tty_flip_buffer_push()") to fix a spinlock lock-up issue when
calling tty_flip_buffer_push(). However, since then commit a9c3f68f3c
("tty: Fix low_latency BUG") migrated tty_flip_buffer_push() to always
use a workqueue, allowing tty_flip_buffer_push() to be called from
within atomic sections. Therefore, we can remove the unlocking of the
spinlock from the DMA callback and UART ISR and this will ensure that
the race condition no longer occurs.

Reported-by: Christopher Freeman <cfreeman@nvidia.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-17 21:07:57 -07:00
Jon Hunter 8f8e48f4d6 serial: tegra: Fix memory leak on DMA setup failure
If the call to dmaengine_slave_config() fails, then the DMA buffer will
not be freed/unmapped. Fix this by moving the code that stores the
address of the buffer in the tegra_uart_port structure to before the
call to dmaengine_slave_config().

Reported-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-24 12:53:44 -07:00
Jon Hunter ad909b3f8b serial: tegra: Correct error handling on DMA setup
Function tegra_uart_dma_channel_allocate() does not check that
dma_map_single() mapped the DMA buffer correctly. Add a check for this
and appropriate error handling.

Furthermore, if dmaengine_slave_config() (called by
tegra_uart_dma_channel_allocate()) fails, then memory allocated/mapped
is not freed/unmapped. Therefore, call tegra_uart_dma_channel_free()
instead of just dma_release_channel() if  dmaengine_slave_config() fails.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10 19:12:19 +02:00
Jon Hunter d92aca3a76 serial: tegra: Correct shutdown of UARTs
There are two issues in the shutdown path of the UARTs which are:
1. The function tegra_uart_shutdown() calls tegra_uart_flush_buffer()
   to stop DMA TX transfers. However, tegra_uart_flush_buffer() is
   called after the DMA channels have already been freed and so actually
   does nothing.
2. The function that frees the DMA channels
   (tegra_uart_dma_channel_free()), unmaps the dma buffer before
   freeing the DMA channel and does not ensure the DMA has been
   stopped.

Resolve this by fixing the code in tegra_uart_dma_channel_free() to
ensure the DMA is stopped, free the DMA channel and then unmap the DMA
buffer. Finally, remove the unnecessary call to tegra_uart_flush_buffer().

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10 19:12:19 +02:00
Jon Hunter 49433c802c serial: tegra: Fix cookie used by TX channel
The DMA cookie for the RX channel is being used by the TX channel.
Therefore, fix driver to use the correct DMA cookie for the TX channel.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10 19:12:19 +02:00
Jon Hunter 0b0c1bdf7a serial: tegra: Use unsigned types for RX and TX byte counts
The function tty_insert_flip_string() takes an argument "size" which is
of type size_t. This is an unsigned type. Update the count,
rx_bytes_requested and tx_bytes_requested in the tegra serial driver to
be unsigned integers so that an unsigned type is passed to
tty_insert_flip_string().

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10 19:12:19 +02:00
Shardar Shariff Md 853a699739 serial: tegra: handle race condition on uart rx side
The tegra serial driver has two paths through which receive data is
copied up to the tty layer. These are:
1. DMA completion callback
2. UART RX interrupt

A UART RX interrupt occurs for either RX_TIMEOUT (data has been sitting
in the Rx FIFO for more than 4 character times without being read
because there is not enough data to reach the trigger level), End of
Receive Data event (receiver detects that data stops coming in for more
than 4 character times) or a receive error.

In the RX interrupt path, the following happens ...
- All RX DMA transfers are stopped
- Any data in the DMA buffer and RX FIFO are copied up to the tty layer.
- DMA is restarted/primed for the RX path

In the DMA completion callback, the DMA buffer is copied up to the tty
layer but there is no check to see if the RX interrupt could have
occurred between the DMA interrupt firing the the DMA callback running.
Hence, if a RX interrupt was to occur shortly after the DMA completion
interrupt, it is possible that the RX interrupt path has already copied
the DMA buffer before the DMA callback has been called. Therefore, when
the DMA callback is called, if the DMA is already in-progress, then this
indicates that the UART RX interrupt has already occurred and there is
nothing to do in the DMA callback. This race condition can cause
duplicated data to be received.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
[jonathanh@nvidia.com: Moved async_tx_ack() call to after check to see
 if DMA has completed because if the DMA is in progress we do not need
 to ACK yet. Changed the print from dev_info to dev_debug. Updated
 changelog to add more commentary on the race condition based upon
 feedback from author.]
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10 19:12:19 +02:00
Shardar Shariff Md db8e78474e serial: tegra: check the count and read if any from dma
It is only necessary to read data from the dma buffer when the count
value is non-zero and hence, tegra_uart_copy_rx_to_tty() so only be
called when this is the case.

Although, this was being tested for in two places, there is a third
place where this was not tested. However, instead of adding another
if-statement prior to calling tegra_uart_copy_rx_to_tty(), move the test
inside the function.

Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com>
[jonathanh@nvidia.com: Re-worked patch to move the check for the count
 value inside the function tegra_uart_copy_rx_to_tty(). Updated
 changelog with more commentary.]
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10 19:12:18 +02:00
Jon Hunter 11e71007a5 serial: tegra: Add delay after enabling FIFO mode
For all tegra devices (up to t210), there is a hardware issue that
requires software to wait for 3 UART clock periods after enabling
the TX fifo, otherwise data could be lost.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10 19:12:18 +02:00
Jon Hunter 245c0278ab serial: tegra: Correct delay after TX flush
For all tegra devices (up to t210), there is a hardware issue that
requires software to wait for 32 UART clock periods for the flush
to propagate otherwise TX data could be post. Add a helper function
to wait for N UART clock periods and update delay following FIFO
flush to be 32 UART clock cycles.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-10 19:12:18 +02:00
Fabian Frederick ed0bb2323c tty: constify of_device_id array
of_device_id is always used as const.
(See driver.of_match_table and open firmware functions)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Acked-by: Timur Tabi <timur@tabi.org>
Acked-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26 22:49:10 +01:00
Johan Hovold f0c1e46045 serial: tegra: clean up tty-flag assignments
The tty break and error flags are not bit masks so do not to use bitwise
OR when assigning them.

Note that there is no functional change due to the if-else construct and
flag having been initialised to zero (TTY_NORMAL).

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-25 17:06:39 -08:00
Peter Hurley 479e9b94fd serial: Refactor uart_flush_buffer() from uart_close()
In the context of the final tty & port close, flushing the tx
ring buffer after the hardware has already been shutdown and
the ring buffer freed is neither required nor desirable.

uart_flush_buffer() performs 3 operations:
1. Resets tx ring buffer indices, but the tx ring buffer has
   already been freed and the indices are reset if the port is
   re-opened.
2. Calls uart driver's flush_buffer() method
   5 in-tree uart drivers define flush_buffer() methods:
     amba-pl011, atmel-serial, imx, serial-tegra, timbuart
   These have been refactored into the shutdown() method, if
   required.
3. Kicks the ldisc for more writing, but this is undesirable.
   The file handle is being released; any waiting writer will
   will be kicked out by tty_release() with a warning. Further,
   the N_TTY ldisc may generate SIGIO for a file handle which
   is no longer valid.

Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-05 18:53:54 -08:00
Pradeep Goudagunta b31245b942 serial: tegra: ack the rx dma desc after transfer terminated
The Rx dma descriptor allocated without the DMA_ACK flags so that
once after tarnsfer done or terminated, client can ack the descriptor
to free it for later use.

If the Rx DMA is terminated for some reason then rx-dma descriptor
is not getting acked which causes the memory leak and list of usage
desc to grow continuously.

Hence, acknowledge the rx-dma descriptor once transfer is terminated
to avoid memory leak and desc list to grow.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-10 15:53:20 -07:00
Pradeep Goudagunta 5e3dbfca3b serial: tegra: update tx_circular buffer only when TX_DMA is in progress
When channel is require to stop transmit then update the Tx circular
buffer only when DMA based transfer is in progress. If there is no
DMA based transfer then no need to update the Tx buffer.

Signed-off-by: Pradeep Goudagunta <pgoudagunta@nvidia.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-10 15:53:20 -07:00
Stephen Warren c2b329f561 serial: tegra: convert to standard DMA DT bindings
By using dma_request_slave_channel_or_err(), the DMA slave ID can be
looked up from standard DT properties, and squirrelled away during
channel allocation. Hence, there's no need to use a custom DT property
to store the slave ID.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
2013-12-11 16:44:35 -07:00