OMAPDSS: fix build when DEBUG_FS or DSS_DEBUG_SUPPORT disabled

If CONFIG_DEBUG_FS or CONFIG_OMAP2_DSS_DEBUG_SUPPORT is disabled, the
build fails:

drivers/video/omap2/dss/core.c:197:50: error: static declaration of
'dss_debugfs_create_file' follows non-static declaration
drivers/video/omap2/dss/dss.h:166:5: note: previous declaration of
'dss_debugfs_create_file' was here

This patch fixes the dummy dss_debugfs_create_file() so that the driver
builds.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
OMAPDSS: Taal: fix compilation warning

This patch fixes a warning:

drivers/video/omap2/displays/panel-taal.c: In function
‘taal_num_errors_show’:
drivers/video/omap2/displays/panel-taal.c:529: warning: ‘errors’ may be
used uninitialized in this function

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
OMAPDSS: fix bogus WARN_ON in dss_runtime_put()

pm_runtime_put_sync() in dss_runtime_put() returns -EBUSY when any child
of dss is still enabled. This happens, for example, when a display
output is enabled and one dumps the clocks via debugfs. This causes
dss_runtime_get & put to be called.

While I couldn't find anything about this in the documentation and it
wasn't immediately clear from runtime_pm code, it looks to me that
pm_runtime_put_sync() returns -EBUSY to inform that things went fine,
but the device could not be turned off as there are still child devices
that are enabled. This is not a problem.

This patch skips the WARN_ON if pm_runtime_put_sync() returns -EBUSY.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
OMAPDSS: DSI: Fix bug when calculating LP command interleaving parameters

In function dsi_compute_interleave_lp(), the escape clock/LP clock time period
is calculated incorrectly. The escape clock/LP clock is calculated as:

LP Clock(Hz) = DSI_FCLK(Hz) / lp_clk_div

Since we are calculating the time period of LP clock, the LP clock divider
should be multiplied with the time period of DSI_FCLK.

Calculating incorrect value of txclkesc results in incorrect calculation of LP
interleaving parameters, it also creates a possibility of a divide by zero
error.

Reported-by: Sureshkumar Manimuthu <mail2msuresh@ti.com>

Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
OMAPDSS: fix registration of DPI and SDI devices

The omapdss arch initialization code registers all the output devices as
omap_devices. However, DPI and SDI are not proper omap_devices, as they
do not have any corresponding HWMOD. This leads to crashes or problems
when the platform code tries to use omap_device functions for DPI and
SDI devices.

One such crash was reported by John Stultz <johnstul@us.ibm.com>:

[   18.756835] Unable to handle kernel NULL pointer dereference at
virtual addr8
[   18.765319] pgd = ea6b8000
[   18.768188] [00000018] *pgd=aa942831, *pte=00000000, *ppte=00000000
[   18.774749] Internal error: Oops: 17 [#1] SMP ARM
[   18.779663] Modules linked in:
[   18.782836] CPU: 0    Not tainted  (3.5.0-rc1-dirty #456)
[   18.788482] PC is at _od_resume_noirq+0x1c/0x78
[   18.793212] LR is at _od_resume_noirq+0x6c/0x78
[   18.797943] pc : [<c00307ec>]    lr : [<c003083c>]    psr: 20000113
[   18.797943] sp : ec3abe80  ip : ec3abdb8  fp : 00000006
[   18.809936] r10: ec1148b8  r9 : c08a48f0  r8 : c00307d0
[   18.815368] r7 : 00000000  r6 : 00000000  r5 : ec114800  r4 :
ec114808
[   18.822174] r3 : 00000000  r2 : 00000000  r1 : ec154fe8  r0 :
00000006
[   18.829010] Flags: nzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM
Segment user
[   18.836456] Control: 10c5387d  Table: aa6b804a  DAC: 00000015
[   18.842437] Process sh (pid: 1139, stack limit = 0xec3aa2f0)
[   18.848358] Stack: (0xec3abe80 to 0xec3ac000)

DPI and SDI can be plain platform_devices. This patch changes the
registration from omap_device_register() to platform_device_add().

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reported-by: John Stultz <johnstul@us.ibm.com>
Tested-by: Jean Pihet <jean.pihet@newoldbits.com>
Merge tag 'omapdss-for-3.5-rc2' of git://gitorious.org/linux-omap-dss2/linux

Pull omapdss build problem fix from Tomi Valkeinen:
 "Small fixes for omapdss driver.  Most importantly, fixes a build
  problem when debugfs or omapdss debug support is turned off, and fixes
  a suspend related crash."

This has apparently been annoying rmk for a while..

* tag 'omapdss-for-3.5-rc2' of git://gitorious.org/linux-omap-dss2/linux:
  OMAPDSS: fix registration of DPI and SDI devices
  OMAPDSS: DSI: Fix bug when calculating LP command interleaving parameters
  OMAPDSS: fix bogus WARN_ON in dss_runtime_put()
  OMAPDSS: Taal: fix compilation warning
  OMAPDSS: fix build when DEBUG_FS or DSS_DEBUG_SUPPORT disabled