There are platforms where the DSI output can be connected to another
encoder bridge chip (DSI to HDMI, DSI to LVDS etc).

Add support for external bridge support to the dsi driver. We assume that
the external bridge chip would be of the type drm_bridge. The dsi driver's
internal drm_bridge (msm_dsi->bridge) is linked to the external bridge's
drm_bridge struct.

In the case we're connected to an external bridge, we don't need to create
and manage a connector within our driver, it's the bridge driver's
responsibility to create one.

v2:
- Move the external bridge attaching stuff to dsi manager to make things
  cleaner.
- Force the bridge to connect to a video mode encoder for now (the dsi
  mode flags may have not been populated by modeset_init)
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

We currently support only panels connected to dsi output. We're going to
also support external bridge chips now.

Change 'panel_node' to 'device_node' in the struct msm_dsi_host and
'panel_flags' to 'device_flags' in msm_dsi. This makes things sound a
bit more generic.
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

Platforms containing only DSI video mode devices don't need a TE gpio.
Make TE gpio optional.
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

The dsi host looks for the connected panel node by parsing for a child
named 'panel'. This hierarchy isn't very flexible. The connected
panel is forced to be a child to the dsi host, and hence, a mipi dsi
device. This isn't suitable for dsi devices that don't use mipi dsi
as their control bus.

Follow the of_graph approach of creating ports and endpoints to
represent the connections between the dsi host and the panel connected
to it. In our case, the dsi host will only have one output port, linked
to the panel's input port.

Update DT binding documentation with device graph usage info.

v3:
- Fix return value checks of of_graph_* calls.
- Don't make port a mandatory DT property
- Fix defer check when no panel node specified
- Rename parse_dt func to align with other dsi_host funcs
Reviewed-by: NHai Li <hali@codeaurora.org>
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

Decrement device node refcount if of_get_child_by_name is successfully
called.
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

DSI PHY errors are falsely reported whenever a dsi error occurs. This is
because DSI_DLN0_PHY_ERR isn't only used as a status register, but also
used to mask PHY errors. Currently, we end up reading the mask bits too
and therefore always report errors.

Ignore the register mask bits and check for only the status/clear bits.
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

DSI controller on msm8x94 is version 1.3, which requires different
power supplies and works with 20nm DSI PHY. This change is to add
the basic support for this version.
Signed-off-by: NHai Li <hali@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

Some targets use pinctrl framework to configure some
pins. This change allows DSI driver to set default and
sleep pinctrl status.
Signed-off-by: NHai Li <hali@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

I'm not sure where, exactly, but somewhere in here we must be relying on
an implicit include.

drivers/gpu/drm/msm/dsi/dsi_host.c: In function ‘dsi_host_init_panel_gpios’:
drivers/gpu/drm/msm/dsi/dsi_host.c:1356:2: error: implicit declaration of function ‘devm_gpiod_get’ [-Werror=implicit-function-declaration]
  msm_host->disp_en_gpio = devm_gpiod_get(panel_device,
  ^
drivers/gpu/drm/msm/dsi/dsi_host.c:1356:25: warning: assignment makes pointer from integer without a cast [enabled by default]
  msm_host->disp_en_gpio = devm_gpiod_get(panel_device,
                         ^
drivers/gpu/drm/msm/dsi/dsi_host.c:1364:3: error: implicit declaration of function ‘gpiod_direction_output’ [-Werror=implicit-function-declaration]
   ret = gpiod_direction_output(msm_host->disp_en_gpio, 0);
   ^
drivers/gpu/drm/msm/dsi/dsi_host.c:1371:20: warning: assignment makes pointer from integer without a cast [enabled by default]
  msm_host->te_gpio = devm_gpiod_get(panel_device, "disp-te");
                    ^
drivers/gpu/drm/msm/dsi/dsi_host.c:1378:3: error: implicit declaration of function ‘gpiod_direction_input’ [-Werror=implicit-function-declaration]
   ret = gpiod_direction_input(msm_host->te_gpio);
   ^
drivers/gpu/drm/msm/dsi/dsi_host.c: In function ‘msm_dsi_host_power_on’:
drivers/gpu/drm/msm/dsi/dsi_host.c:1918:3: error: implicit declaration of function ‘gpiod_set_value’ [-Werror=implicit-function-declaration]
   gpiod_set_value(msm_host->disp_en_gpio, 1);
   ^
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Hai Li <hali@codeaurora.org>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: NRob Clark <robdclark@gmail.com>

Since 39b2bbe3 (gpio: add flags argument to gpiod_get*() functions)
which appeared in v3.17-rc1, the gpiod_get* functions take an additional
parameter that allows to specify direction and initial value for output.

Also there is a variant to find optional gpios that returns NULL if
there is no gpio instead of -ENOENT.

Make use of both features to simplify the driver.

This makes error checking more strict because errors like -ENOSYS ("no
gpio support compiled in") or -EPROBE_DEFER ("gpio not ready yet") are
handled correctly now.

Furthermore this is one caller less that stops us making the flags
argument to gpiod_get*() mandatory.
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NRob Clark <robdclark@gmail.com>

There are different types of PHY from one chipset to another, while
the DSI host controller is relatively consistent across platforms.
Also, the PLL inside PHY is providing the source of DSI byte and
pixel clocks, which are used by DSI host controller. Separated devices
for clock provider and clock consumer make DSI driver better fit into
common clock framework.
Signed-off-by: NHai Li <hali@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

This change activates PLL driver for DSI to work with
common clock framework.
Signed-off-by: NHai Li <hali@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

DSI byte clock and pixel clocks are sourced from DSI PLL.
This change adds the DSI PLL source clock driver under
common clock framework.

This change handles DSI 28nm PLL only.
Signed-off-by: NHai Li <hali@codeaurora.org>
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Signed-off-by: NStephane Viau <sviau@codeaurora.org>
Signed-off-by: NWentao Xu <wentaox@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

regulator_get() never returns NULL. There's no need for IS_ERR_OR_NULL()
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NRob Clark <robdclark@gmail.com>

Some DSI peripherals rely on the HS clock on DSI clock lane as their clock
source. If the clock lane transitions between HS and LP states, it
can disrupt the functioning of such peripherals.

The mipi dsi mode flag MIPI_DSI_CLOCK_NON_CONTINUOUS already exists for
such peripheral drivers. Use it to configure the bit CLKLN_HS_FORCE_REQUEST
in DSI_LANE_CTRL.
Signed-off-by: NArchit Taneja <architt@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>

During cmd rx, only new versions of H/W provide register to read back
the real number of byte returned by panel. For the old versions, reading
this register will not get the right number. In fact, we only need to
assume the returned data is the same size as we expected, because later
we will check the data type to detect error.
Signed-off-by: NHai Li <hali@codeaurora.org>

When things go badly we can get a lot of these error irqs.  Let's not
DoS the user.
Signed-off-by: NRob Clark <robdclark@gmail.com>

Signed-off-by: NHai Li <hali@codeaurora.org>

Avoid such errors at compilation time:
	format '%d' expects argument of type 'int', but argument 3 has type 'size_t'
Signed-off-by: NStephane Viau <sviau@codeaurora.org>

This change adds the DSI connector support in msm drm driver.

v1: Initial change
v2:
- Address comments from Archit + minor clean-ups
- Rebase to not depend on msm_drm_sub_dev change [Rob's comment]
v3: Fix issues when initialization is failed
Signed-off-by: NHai Li <hali@codeaurora.org>
Signed-off-by: NRob Clark <robdclark@gmail.com>