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path: root/drivers/gpu/drm/tilcdc/tilcdc_crtc.c
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2016-09-07drm/tilcdc: Clean up LCDC functional clock rate setting codeJyri Sarha
Clean up LCDC functional clock rate setting code. The LCDC functional clock is set by two functions: mode_set_nofb() and cpufreq_transition(). When tilcdc_crtc_mode_set_nofb() is called in atomic commit phase the drm atomic helpers have taken all the necessary drm locks and turned off the crtc, while tilcdc_commit() is keeping LCDC powered on. For mode_set_nofb() just a simple clock setting function without any locking or power management code is enough. The new tilcdc_crtc_set_clk() is implemented for that purpose. cpufreq_transition() on the other hand is called from outside DRM and it needs to take the necessary locks and turn off the CRTC while keeping the LCDC powered. The reimplemented tilcdc_crtc_update_clk() is for that purpose and it uses the new tilcdc_crtc_set_clk() to actually set the clock. Signed-off-by: Jyri Sarha <jsarha@ti.com> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-09-01drm/tilcdc: Write DMA base and ceiling address with single instructionJyri Sarha
Write DMA base and ceiling address with a single instruction, if available. This should make it more unlikely that LCDC would fetch the DMA addresses in the middle of an update. Having bad combination of addresses in dma base and ceiling (e.g base > ceiling) can cause unpredictaple behavior in LCDC. Signed-off-by: Jyri Sarha <jsarha@ti.com> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-09-01drm/tilcdc: Enable EOF interrupts for v1 LCDCKarl Beldan
This got accidentally dropped in the fixed commit and is required for the driver to properly work on the rev1 IP, such as found on the LCDK. Fixes: 2b2080d7e9ae ("drm/tilcdc: Get rid of complex ping-pong mechanism") Signed-off-by: Karl Beldan <kbeldan@baylibre.com> Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-09-01drm/tilcdc: Adjust the FB_CEILING addressKarl Beldan
The LCDC seems to expect its framebuffer ceiling address pointer to be an inclusive bound. The IP rev2 seems to cope with that but rev1 (as found on the LCDK) don't. Also note that this is what the framebuffer code does in da8xx-fb.c. Since, as the TRM puts it, "The 2 LSBs are hardwired to 00b", the dma_addr_t can be decremented without cast. I tested it with a v2 (AM335x, rev 0x4F201000) and an LCDK (v1). Signed-off-by: Karl Beldan <kbeldan@baylibre.com> Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Change tilcdc_crtc_page_flip() to tilcdc_crtc_update_fb()Jyri Sarha
Change tilcdc_crtc_page_flip() to tilcdc_crtc_update_fb(). The function is not used as a page_flip() callback anymore so it is only confusing to call it that. The function should only be used by dummy primary plane commit() callback. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Remove unnecessary pm_runtime_get() and *_put() callsJyri Sarha
Remove unnecessary pm_runtime_get() and *_put() calls from commit phase callbacks. Those calls are not needed since we have the whole commit phase between pm_runtime_get_sync() and pm_runtime_put_sync(). Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Get rid of legacy dpms mechanismJyri Sarha
Get rid of legacy dpms mechanism. This simplifies the code quite a bit. The old start() and stop() functions become tilcdc_crtc_enable() and *_disable(). The functions are added with all the necessary mechanisms from the old dpms function and they are used directly as the crtc helper enable() and disable() callbacks. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Enable and disable interrupts in crtc start() and stop()Jyri Sarha
Enable and disable interrupts in crtc start() and stop(). None of the interrupts can fire if CRTC is disabled, so it is cleaner - when considering suspend/resume code etc. - to enable the interrupts when CRTC is turned on and to disable them when CRTC is turned off. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Remove tilcdc_verify_fb()Jyri Sarha
Remove tilcdc_verify_fb(). The tilcdc_verify_fb() function is not needed because the same checks are implemented in tilcdc_plane_atomic_check(). Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Remove obsolete crtc helper functionsJyri Sarha
Remove obsolete crtc helper functions. These are not needed when atomic modeset is used. Note that the drm_crtc_helper_funcs mode_fixup() is still needed. The crtc's check() callback can not do its job here. The plane's check() callback needs to set drm_crtc_state's ->mode_changed to true if the pixel format for the framebuffer changes. Because of this drm_mode_config_funcs atomic_check() callback needs to call drm_atomic_helper_check_modeset() once more after it has called drm_atomic_helper_check_planes(). If the fixing of the adjusted_mode would be done in drm_crtc_helper_funcs atomic_check() callback, it would get over written by the extra drm_atomic_helper_check_modeset() call. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Set DRIVER_ATOMIC and use atomic crtc helpersJyri Sarha
Set DRIVER_ATOMIC and use atomic helpers and rename commit and prepare crtc helpers to enable and disable. This makes the final jump to mode setting, but there is lot of obsolete code to clean up. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Add tilcdc_crtc_atomic_check()Jyri Sarha
Add tilcdc_crtc_atomic_check(). Checks the display mode validity and the presence of the mandatory primary plane. The drm_crtc_helper_funcs mode_fixup() callback is left untouched and the check function does no try to do its job on purpose, despite what the mode_fixup() callback's documentations suggests. The plane's check() callback needs to set drm_crtc_state's ->mode_changed to true if the pixel format for the framebuffer changes. Because of this drm_mode_config_funcs atomic_check() callback needs to call drm_atomic_helper_check_modeset() once more after it has called drm_atomic_helper_check_planes(). If the fixing of the adjusted_mode would be done in drm_crtc_helper_funcs atomic_check() callback, it would get over written by the extra drm_atomic_helper_check_modeset() call. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Add tilcdc_crtc_mode_set_nofb()Jyri Sarha
Add tilcdc_crtc_mode_set_nofb(). The mode_set_nofb() semantics do not fit well to LCDC, because of the mandatory framebuffer. However, when the primary plane is required in the check phase, it and the framebuffer can be found from the atomic state struct. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Initialize dummy primary plane from crtc initJyri Sarha
Initialize dummy primary plane from crtc init. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Make tilcdc_crtc_page_flip() work if crtc is not yet onJyri Sarha
Make tilcdc_crtc_page_flip() work if crtc is not yet on. The plane commit sometimes comes before crtc is turned on. The new framebuffer should be set to scanout also in that case, so that it is there when crtc is turned on at the end of the commit phase. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Make tilcdc_crtc_page_flip() publicJyri Sarha
Make tilcdc_crtc_page_flip() public for dummy plane implementation to use. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Call drm_crtc_vblank_on() and *_off() in start() and stop()Jyri Sarha
Add drm_crtc_vblank_on() and *_off() calls to start() and stop() functions, to make sure any vblank waits etc. gets properly cleaned up. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Increase time out for waiting frame done interruptJyri Sarha
Increase time out for waiting frame done interrupt. 50ms is long enough for the usual display modes (50 Hz or higher refresh rate), but it may be a bit tight for some unusual mode. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Move waiting of LCDC_FRAME_DONE IRQ into stop()Jyri Sarha
Move wait queue waiting of LCDC_FRAME_DONE IRQ from tilcdc_crtc_dpms() into stop() function. This is just a cleanup and enables independent use of stop() function. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Write to LCDC_END_OF_INT_IND_REG at the end of IRQ functionJyri Sarha
Reorder the IRQ function so that the write to LCDC_END_OF_INT_IND_REG is done last. The write to LCDC_END_OF_INT_IND_REG indicates to LCDC that the interrupt service routine has completed (see section 13.3.6.1.6 in AM335x TRM). This is needed if LCDC's ipgvmodirq module is configured for pulse interrupts. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Move LCDC_SYNC_LOST handling inside if (ver == 2) statementJyri Sarha
Move LCDC_SYNC_LOST handling inside if (ver == 2) statement. LCDC_SYNC_LOST interrupt status bit is only defined for version 2 silicon. Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-08-08drm/tilcdc: Restore old dpms state in pm_resume()Jyri Sarha
Restore old dpms state in pm_resume(). The dpms is turned off in pm_suspend() and it should be restored to its original state in pm_resume(). Without this patch the display is left blanked after a suspend/resume cycle. Fixes commit 614b3cfeb8d2 ("drm/tilcdc: disable the lcd controller/dma engine when suspend invoked") Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-07-12drm/tilcdc: use drm_crtc_handle_vblank()Gustavo Padovan
Remove legacy usage of drm_handle_vblank() Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1467677092-5089-6-git-send-email-gustavo@padovan.org
2016-05-02drm/tilcdc: use drm_crtc_send_vblank_event()Gustavo Padovan
Replace the legacy drm_send_vblank_event() with the new helper function. Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Reviewed-by: Jyri Sarha <jsarha@ti.com> Tested-by: Jyri Sarha <jsarha@ti.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1460656118-16766-11-git-send-email-gustavo@padovan.org
2016-02-25drm/tilcdc: Use devm_kzalloc() and devm_kcalloc() for private dataJyri Sarha
Use devm_kzalloc() and devm_kcalloc() for private data allocation at driver load time. Signed-off-by: Jyri Sarha <jsarha@ti.com> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-02-25drm/tilcdc: Initialize crtc->portJyri Sarha
Initialize port device node pointer in the tilcdc crtc. Fixes "Falling back to first CRTC" warning from tda998x driver. The tda998x encoder driver calls drm_of_find_possible_crtcs() to initialize possible_crtcs of struct drm_encoder. The crtc->port needs to be initialized for drm_of_find_possible_crtcs() to work. Signed-off-by: Jyri Sarha <jsarha@ti.com> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-02-25drm/tilcdc: Disable sync lost interrupt if it fires on every frameJyri Sarha
Disable the sync lost interrupt if it fires on every frame for 50 consecutive frames in a row. This is relatively sure sign of the sync lost interrupt being stuck and firing on every frame even if the display otherwise appears to work OK. Signed-off-by: Jyri Sarha <jsarha@ti.com> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-02-25drm/tilcdc: Add prints on sync lost and FIFO underrun interruptsJyri Sarha
Add ratelimited prints on sync lost and FIFO underrun interrupts. Signed-off-by: Jyri Sarha <jsarha@ti.com> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-02-25drm/tilcdc: Do not update the next frame buffer close to vertical blankTomi Valkeinen
Do not update the next frame buffer close to vertical blank. This is to avoid situation when the frame changes between writing of LCDC_DMA_FB_BASE_ADDR_0_REG and LCDC_DMA_FB_CEILING_ADDR_0_REG. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> [Added description to the patch] Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-02-25drm/tilcdc: Get rid of complex ping-pong mechanismTomi Valkeinen
Get rid of complex ping-pong mechanism and replace it with simpler single buffer flipping code. The LCDC HW appears to be designed mainly static framebuffers in mind. There are two modes of operation, either static single buffer, or ping pong double buffering with two static buffers switching back and forth. Luckily the framebuffer start address is fetched only in the beginning of the frame and changing the address after that only takes effect after the next vertical blank. The page flipping code can simply write the address of the new framebuffer and the page is flipped automatically after the next vertical blank. Using the ping pong double buffering makes the flipping code way more complex and it does not provide any benefit, so it is better to switch to single buffer operation. There is still one problem in updating the framebuffer dma address on the fly. There are two registers defining the framebuffer dma area and things may break if the dma address is fetched in while the registers are are being updated. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> [Added description to the patch] Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-02-25drm/tilcdc: cleanup irq handlingTomi Valkeinen
Cleanup irq handling. Clear the irq status unconditionally and restructure the status bit conditions. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> [Added description to the patch] Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-02-25drm/tilcdc: remove broken error handlingTomi Valkeinen
Remove broken error handling. The condition for handling the LCDC_SYNC_LOST and LCDC_FIFO_UNDERFLOW could never be satisfied as the LCDC_SYNC_LOST interrupt is not enabled. Also the requirement to have both LCDC_SYNC_LOST and LCDC_FIFO_UNDERFLOW fired at once before handling the error looks weird. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> [Added description to the patch] Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-02-25drm/tilcdc: split reset to a separate functionTomi Valkeinen
Split reset to a separate function and use usleep_range(250, 1000) instead of msleep(1) to to keep the reset bit on long enough. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> [Added description to the patch, changed mdelay(500) to usleep_range(250, 1000)] Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-02-25drm/tilcdc: cleanup runtime PM handlingTomi Valkeinen
Cleanup runtime PM handling. Before the patch the usage of pm_runtime calls was inconsistent and hard to follow. After the update the pm_runtime calls are removed from set_scanout() and called around major operations that access the HW. After the patch the DPMS code does not have pm_runtime_forbid/allow calls any more and pm_runtime_irq_safe() is not set anymore. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> [Added description to the patch] Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-02-25drm/tilcdc: disable the lcd controller/dma engine when suspend invokedDarren Etheridge
The LCD controller must be deactivated and all DMA transactions stopped when the suspend power state is entered otherwise the PRCM causes the L3 bus to get stuck in transition state. This commit forces the lcdc to be shut down and waits for all pending DMA transactions to complete as part of the suspend handler for this driver. Signed-off-by: Darren Etheridge <detheridge@ti.com> Tested-by: Dave Gerlach <d-gerlach@ti.com> Signed-off-by: Jyri Sarha <jsarha@ti.com> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-02-25drm/tilcdc: verify fb pitchTomi Valkeinen
LCDC hardware does not support fb pitch that is different (i.e. larger) than the screen size. The driver currently does no checks for this, and the results of too big pitch are are flickering and lower fps. This issue easily happens when using libdrm's modetest tool with non-32 bpp modes. As modetest always allocated 4 bytes per pixel, it implies a bigger pitch for 16 or 24 bpp modes. This patch adds a check to reject pitches the hardware cannot support. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> Signed-off-by: Darren Etheridge <detheridge@ti.com> Signed-off-by: Jyri Sarha <jsarha@ti.com>
2016-02-25drm/tilcdc: rewrite pixel clock calculationDarren Etheridge
Updating the tilcdc DRM driver code to calculate the LCD controller pixel clock more accurately. Based on a suggested implementation by Tomi Valkeinen. The current code does not work correctly and produces wrong results with many requested clock rates. It also oddly uses two different clocks, a display pll clock and a divider clock (child of display pll), instead of just using the clock coming to the lcdc. This patch removes the use of the display pll clock, and rewrites the code to calculate the clock rates. The idea is simply to request a clock rate of pixelclock*2, as the LCD controller has an internal divider which we set to 2. Signed-off-by: Darren Etheridge <detheridge@ti.com> [Rewrapped description] Signed-off-by: Jyri Sarha <jsarha@ti.com> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2016-02-08drm/tilcdc: Nuke preclose hookDaniel Vetter
Again since the drm core takes care of event unlinking/disarming this is now just needless code. v2: Fixup misplaced hunks. Cc: Rob Clark <robdclark@gmail.com> Acked-by: Daniel Stone <daniels@collabora.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v1) Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1453756616-28942-13-git-send-email-daniel.vetter@ffwll.ch
2015-05-27drm/tilcdc: Add support for external tda998x encoderJyri Sarha
Add support for an external compontised DRM encoder. The external encoder can be connected to tilcdc trough device tree graph binding. The binding document for tilcdc has been updated. The current implementation supports only tda998x encoder. To be able to filter out the unsupported video modes the tilcdc driver needs to hijack the external connectors helper functions. The tilcdc installes new helper functions that are otherwise identical to orignals, but the mode_valid() call-back check the mode first localy, before calling the original call-back. The tilcdc dirver restores the original helper functions before it is unbound from the external device. I got the idea and some lines of code from Jean-Francois Moine's "drm/tilcdc: Change the interface with the tda998x driver"-patch. Signed-off-by: Jyri Sarha <jsarha@ti.com> Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2015-05-27drm/tilcdc: Fix module unloadingJyri Sarha
Force crtc dpms off before destroying the crtc instead of just checking the dpms state. This fixes warning message and frozen picture after tilcdc module unloading. Signed-off-by: Jyri Sarha <jsarha@ti.com> Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
2014-11-15drm: flip-work: change drm_flip_work_init prototypeBoris BREZILLON
Now that we're using lists instead of kfifo to store drm flip-work tasks we do not need the size parameter passed to drm_flip_work_init function anymore. Moreover this function cannot fail anymore, we can thus remove the return code. Modify drm_flip_work_init users to take account of these changes. [airlied: fixed two unused variable warnings] Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com> Reviewed-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-11-05drm: Move drm_crtc_init from drm_crtc.h to drm_plane_helper.hDaniel Vetter
Just a bit of OCD cleanup on headers - this function isn't the core interface any more but just a helper for drivers who haven't yet transitioned to universal planes. Put the declaration at the right spot and sprinkle necessary #includes over all drivers. Maybe this helps to encourage driver maintainers to do the switch. v2: Fix #include ordering for tegra, reported by 0-day builder. v3: Include required headers, reported by Thierry. Cc: Matt Roper <matthew.d.roper@intel.com> Cc: Thierry Reding <treding@nvidia.com> Reviewed-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
2014-04-01drm: Replace crtc fb with primary plane fb (v3)Matt Roper
Now that CRTC's have a primary plane, there's no need to track the framebuffer in the CRTC. Replace all references to the CRTC fb with the primary plane's fb. This patch was generated by the Coccinelle semantic patching tool using the following rules: @@ struct drm_crtc C; @@ - (C).fb + C.primary->fb @@ struct drm_crtc *C; @@ - (C)->fb + C->primary->fb v3: Generate patch via coccinelle. Actual removal of crtc->fb has been moved to a subsequent patch. v2: Fixup several lingering crtc->fb instances that were missed in the first patch iteration. [Rob Clark] Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Reviewed-by: Rob Clark <robdclark@gmail.com>
2013-08-30drm: Pass page flip ioctl flags to driverKeith Packard
This lets drivers see the flags requested by the application [airlied: fixup for rcar/imx/msm] Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Dave Airlie <airlied@gmail.com>
2013-08-19drm/tilcdc: use flip-work helperRob Clark
Signed-off-by: Rob Clark <robdclark@gmail.com> Tested-by: Darren Etheridge <detheridge@ti.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-08-19drm/tilcdc fixup mode to workaround sync for tda998xDarren Etheridge
Add a fixup function that will flip the hsync priority and add a hskew value that is used to shift the tda998x to the right by a variable number of pixels depending on the mode. This works around an issue with the sync timings that tilcdc is outputing. Signed-off-by: Darren Etheridge <detheridge@ti.com> Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> Tested-by: Russell King <rmk_kernel@arm.linux.org.uk> Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-06-28drm/tilcdc: Clear bits of register we're going to set.Pantelis Antoniou
Bits weren't cleared so resolution changes didn't work. Signed-off-by: Pantelis Antoniou <panto@antoniou-consulting.com> Signed-off-by: Darren Etheridge <detheridge@ti.com> Acked-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-06-28drm/tilcdc: whitespace fixes and tidyupDarren Etheridge
keeping checkpatch happy. Signed-off-by: Darren Etheridge <detheridge@ti.com> Acked-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-06-28drm/tilcdc: adding more guards to prevent selection of invalid modesDarren Etheridge
The tilcdc has a number of limitations for the allowed sizes of the various adjustable timing parameter. Some modes are outside of these timings. This commit will prune modes that report timings that will overflow the allowed sizes in the tilcdc. Signed-off-by: Darren Etheridge <detheridge@ti.com> Acked-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-06-28drm/tilcdc: fixing off by one errors found on analyzerDarren Etheridge
When hooking up to an HDMI analyzer noticed some timings were off by one. Referring to the hardware technical reference manual for the lcd controller some of the timing registers use 0 to represent 1. This patch addresses that issue. Signed-off-by: Darren Etheridge <detheridge@ti.com> Acked-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>