Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}
// </smpl>
Signed-off-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Acked-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

'dsim' is allocated and checked for NULL in the probe function.
Hence this check is redundant. This cleanup also fixes a potential NULL
pointer dereference error when dsim which is NULL references its member
in the error print message.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This code is never executed and hence removed.
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

The value of AUX channel differential amplitude current is changed
from 8 mA to 16 mA, in order to increase AUX channel voltage level.
In this case, AUX channel voltage level can be changed from 400 mV
to 800 mV, when resistance between AUX TX and RX is 100 ohm.

According to DP spec, although the normative voltage level is 390 mV,
the informative voltage level is 430 mV. So, 800 mV can be helpful
to improve voltage margin of AUX channel.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This patch adds bit-masking for LINK_TRAINING_CTL register, when
pre-emphasis level is set. The bit 3 and bit 2 of LINK_TRAINING_CTL
register are used for pre-emphasis level setting, so other bits
should be masked.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

To check channel equalization, the value of LANE_ALIGN_STATUS_UPDATED is
necessary in exynos_dp_channel_eq_ok(). Also, link_align includes this value.
However, link_status does not include this value, so it makes the problem
that channel equalization is failed during link training.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

SW reset sets DP TX to initial value, so configurations for analog parameter
and interrupt are not set properly. Therefore, exynos_dp_init_analog_param()
and exynos_dp_init_interrupt() should be moved to after sw reset is called,
in order to set these values properly.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This patch changes return type of exynos_dp_init_video to void,
because the return value is unnecessary.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Fix the return value of exynos_dp_get_pll_lock_status to
reflect what it actually returns.
Signed-off-by: NSean Paul <seanpaul@chromium.org>
Reviewed-by: NOlof Johansson <olofj@chromium.org>
Acked-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This patch adds the function name to aux transaction failure messages
so we can tell which transaction is failing. It also changes the level
of Aux Transaction fail messages from error to debug. We retry the
transactions a few times and will report errors if warranted outside of
this function.
Signed-off-by: NSean Paul <seanpaul@chromium.org>
Reviewed-by: NDoug Anderson <dianders@chromium.org>
Reviewed-by: NBernie Thompson <bhthompson@chromium.org>
Acked-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This patch checks time loop for RPLY_RECEIV which means that
AUX channel command reply is received.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Fixes the following sparse warnings:
drivers/video/exynos/exynos_mipi_dsi.c:208:22: warning:
symbol 'exynos_mipi_dsi_find_lcd_device' was not declared. Should it be static?
drivers/video/exynos/exynos_mipi_dsi.c:268:22: warning:
symbol 'exynos_mipi_dsi_bind_lcd_ddi' was not declared. Should it be static?
Signed-off-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

The devm_clk_get function allocates memory that is released when a driver
detaches. This patch uses this function for data that is allocated in the probe
function of a platform device and is only freed in the remove function.

Additionally, this patch removes a null check after platform_get_resource that
is redundant with the one done by devm_request_and_ioremap.
Signed-off-by: NDamien Cassou <damien.cassou@lifl.fr>
Acked-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This patch adds adjustement for voltage swing and pre-emphasis during
Link Training procedure. According to the DP specification, unless all
the LANEx_CR_DONE bits are set, the transmitter must read
the ADJUST_REQUEST_LANEx_x, increase the voltage swing according to
the request, and update the TRAINING_LANEx_SET bytes to match the new
voltage swing setting.

Refer to the DP specification v1.1a, Section 3.5.1.3 Link Training.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

When FB_BLANK_UNLANK event occured, exynos mipi dsi regulators have to turn on.
Signed-off-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This patch replaces udelay and mdelay with usleep_range to remove
the busy loop waiting.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

The only INTERLANE_ALIGN_DONE bit should be checked for channel equalization
during Link Training. Previously, the other bits such as LINK_STATUS_UPDATED
were checked, and channel equalization procedure was repeated unnecessarily.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Wrong DPCD addresses were used for clock recovery during Link Training.
The training pattern should be set by TRAINING_PATTERN_SET (0x102), while
voltage swing and pre-emphasis should be set by TRAINING_LANE0_SET (0x103).
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Correct spelling typo in debug messages and comments
within drivers/video.
Signed-off-by: NMasanari Iida <standby24x7@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Commit 9befe40f ("video: backlight:
support s6e8ax0 panel driver based on MIPI DSI") added s6e8ax0.h, but
no file includes it. That's probably a good thing, because it declares
an extern void function that is defined static int in s6e8ax0.c.
Besides, that function is also wrapped in the module_init() macro, which
should do everything needed to make that function available to the code
outside of s6e8ax0.c. This header can safely be removed.
Signed-off-by: NPaul Bolle <pebolle@tiscali.nl>
Acked-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Some functions are declared twice in header file; thus, these
declarations are unnecessary.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This patch fixes build warning due to uninitialized value dereference.

drivers/video/exynos/exynos_dp_core.c: In function 'exynos_dp_set_link_train':
drivers/video/exynos/exynos_dp_core.c:529:18: warning: 'reg' may be used uninitialized in this function [-Wuninitialized]
drivers/video/exynos/exynos_dp_core.c:395:6: note: 'reg' was declared here
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This patch reduces delay time when configuring video setting,
which is helpful to reduce wakeup time during resume.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

The sw reset should be called prioir to enabling sw defined function,
according to datasheet.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

The devm_ functions allocate memory that is released when a driver
detaches. This makes the code smaller and a bit simpler.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

This patch adds panel_reverse variable to support reversed s6e8ax0 panel
type.
Signed-off-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Rework the interrupt handler so the RX_DONE, FIFO_EMPTY interrupts are
properly detected. This prevents missing the interrupts when there are
other bits set in the INTSRC register than just RX_DONE and FIFO_EMPTY.
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Make sure all resources are initialized before interrupt handler is
registered. Pass full platform device name to request_irq() so it
can be distinguished which device has requested an interrupt in cases
there are multiple instances in the system.

Also enable voltage regulators regardless of they have been enabled
by bootloader or not, to make sure other drivers using same regulators
don't disable them unexpectedly.
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Use proper PM ops from struct dev_pm_ops rather than the deprecated ones.
Signed-off-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

MIPI DSI uses 1.1v regulator, so change its supply name.
Signed-off-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Remove unnecessary headers from the file.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

When exynos_mipi_update_cfg() is called, mipi dsi registers were become
sw reset. So, It needs to enable interrupt again.
Signed-off-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

The exynos_mipi_dsi_set_main_disp_[hv]porch() functions take front and
back porch arguments in that order. This maps to the fb_videomode
right/lower_margin and left/upper_margin respectively. Fix the caller
accordingly.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: NDonghwa Lee <dh09.lee@samsung.com>

This patch adds analog and pll control setting. This control setting
is used for DP TX PHY block to set the values as below. It is beneficial
to improve analog characteristics.
 - TX terminal registor is 50 Ohm.
 - Reference clock of PHY is 24 MHz.
 - Power source for TX digital logic is 1.0625 V.
 - Power source for internal clock driver is 1.0625 V.
 - PLL VCO range setting is 600 uA.
 - Power down ring osc is turned off.
 - AUX terminal resistor is 50 Ohm.
 - AUX channel current is 8 mA and multiplied by 2.
 - TX channel output amplitude is 400 mV.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

The char pointer for adjust_request variable is replaced with char array
to fix possible null pointer dereference when clock recovery is failed.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

DP PLL Lock status should be checked in order to  prevent unlocked PLL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Samsung EXYNOS SoC such Exynos5 has DP controller and embedded DP
panel can be used. This patch supports DP driver based on Samsung
EXYNOS SoC chip.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

An moled panel driver based MIPI DSI interface.  S6E8AX0 means it may
includes many other ldi controllers, for example, S6E8AA0, S6E8AB0, and so
on.

This patch can be modified depending on each panel properites.  For
example, second parameter of panel condition register can be changed
depending on ldi controller or amoled type.

[akpm@linux-foundation.org: fix Kconfig syntax error]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Cc: Jingoo Han <jg1.han@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>

Samsung S5PC210 and EXYNOS SoC platform has MIPI-DSI controller and
MIPI-DSI based LCD Panel could be used with it.  This patch supports
MIPI-DSI driver based Samsung SoC chip.

LCD panel driver based MIPI-DSI should be registered to MIPI-DSI driver at
machine code and LCD panel driver specific function registered to
mipi_dsim_ddi structure at lcd panel init function called system init.  In
the MIPI-DSI driver, find lcd panel driver by using registered lcd panel
name, and then initialize lcd panel driver.
Signed-off-by: NDonghwa Lee <dh09.lee@samsung.com>
Signed-off-by: NInki Dae <inki.dae@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Acked-by: NJingoo Han <jg1.han@samsung.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>