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path: root/drivers/gpu/drm/radeon/radeon_display.c
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2011-11-01drm/radeon/kms: remove useless radeon_ddc_dump()Alex Deucher
The function didn't work with DP, eDP, or DP bridge connectors and thus confused users as it lead them to believe nothing was connected or the EDID was invalid when in fact is was, just on the aux bus rather an i2c. It should also speed up module loading as it avoids a bunch of extra DDC probing. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-11-01drm/radeon/kms: rework DP bridge checksAlex Deucher
Return the encoder id rather than a boolean. This is needed for differentiate between multiple DP bridge chips. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-09-14drm/radeon: Unreference GEM object outside of spinlock in page flip error path.Michel Dänzer
Should fix https://bugzilla.redhat.com/show_bug.cgi?id=726277 . Signed-off-by: Michel Dänzer <michel.daenzer@amd.com> cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-09-06drm/radeon/kms: fix DP detect and EDID fetch for DP bridgesAlex Deucher
Sink type is always DP for DP bridges and EDID fetch on DP bridges is always i2c over aux rather than plain i2c. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-08-04drm/radeon: Extended DDC Probing for Connectors with Improperly Wired DDC ↵Thomas Reim
Lines (here: Asus M2A-VM HDMI) Some integrated ATI Radeon chipset implementations with add-on HDMI card (e. g. Asus M2A-VM HDMI) indicate the availability of a DDC even when the add-on card is not plugged in or HDMI is disabled in BIOS setup. In this case, drm_get_edid() and drm_edid_block_valid() periodically dump data and kernel errors into system log files and onto terminals. For these connectors DDC probing is extended by a check for a correct EDID header. Only in case a valid EDID header is also found, the (HDMI or DVI) connector will be used by the Radeon driver. This prevents the kernel driver from useless flooding of logs and terminal sessions with EDID dumps and error messages. This patch adds a flag 'requires_extended_probe' to the radeon_connector structure. In function radeon_connector_needs_extended_probe() this flag can be set on a chipset family/vendor/connector type specific basis. In addition, function radeon_ddc_probe() has been adapted to perform extended DDC probing if required by the connector's flag. Requires function drm_edid_header_is_valid() in DRM module provided by [PATCH] drm: Separate EDID Header Check from EDID Block Check. Tested for kernel 2.6.35, 2.6.38 and 3.0 on Asus M2A-VM HDMI board BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=668196 BugLink: http://bugs.launchpad.net/bugs/7228066 Cc: <stable@kernel.org> Signed-off-by: Thomas Reim <reimth@gmail.com> Reviewed-by: Alex Deucher <alexdeucher@gmail.com> Acked-by: Stephen Michaels <Stephen.Micheals@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-07-14drm/radeon: Don't clobber error return value in page flipping cleanup paths.Michel Dänzer
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-07-14drm/radeon: Don't generate new fence for page flip.Michel Dänzer
Use the fence of the new frontbuffer, if any. Generating a new fence could cause us to wait for completely unrelated rendering to finish before performing the flip. Signed-off-by: Michel Dänzer <michel.daenzer@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-06-02drm/radeon: fix oops in ttm reserve when pageflipping (v2)Dave Airlie
We need to take a reference to this object, pinning doesn't take a reference so if userspace deletes the object it can disappear even if pinned. v2: fix error paths to unreference properly also. should fix: https://bugzilla.kernel.org/show_bug.cgi?id=32402 and https://bugzilla.redhat.com/show_bug.cgi?id=680651 Acked-By: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-05-24drm/radeon/kms/atom: move dig phy init out of modesettingAlex Deucher
It only needs to be called once at startup, not for every modeset. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-04-28drm: Verify debug message argumentsJoe Perches
Add __attribute__((format (printf, 4, 5))) to drm_ut_debug_printk and fix fallout. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-14Merge remote branch 'intel/drm-intel-next' of ../drm-next into drm-core-nextDave Airlie
* 'intel/drm-intel-next' of ../drm-next: (755 commits) drm/i915: Only wait on a pending flip if we intend to write to the buffer drm/i915/dp: Sanity check eDP existence drm/i915: Rebind the buffer if its alignment constraints changes with tiling drm/i915: Disable GPU semaphores by default drm/i915: Do not overflow the MMADDR write FIFO Revert "drm/i915: fix corruptions on i8xx due to relaxed fencing" drm/i915: Don't save/restore hardware status page address register drm/i915: don't store the reg value for HWS_PGA drm/i915: fix memory corruption with GM965 and >4GB RAM Linux 2.6.38-rc7 Revert "TPM: Long default timeout fix" drm/i915: Re-enable GPU semaphores for SandyBridge mobile drm/i915: Replace vblank PM QoS with "Interrupt-Based AGPBUSY#" Revert "drm/i915: Use PM QoS to prevent C-State starvation of gen3 GPU" drm/i915: Allow relocation deltas outside of target bo drm/i915: Silence an innocuous compiler warning for an unused variable fs/block_dev.c: fix new kernel-doc warning ACPI: Fix build for CONFIG_NET unset mm: <asm-generic/pgtable.h> must include <linux/mm_types.h> x86: Use u32 instead of long to set reset vector back to 0 ... Conflicts: drivers/gpu/drm/i915/i915_gem.c
2011-02-23drm/radeon: introduce gem_to_radeon_bo helperDaniel Vetter
... and switch it to container_of upcasting. v2: converted new pageflip code-paths. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-02-23Revert "drm/radeon/kms: switch back to min->max pll post divider iteration"Alex Deucher
This reverts commit a6f9761743bf35b052180f4a8bdae4d2cc0465f6. Remove this commit as it is no longer necessary. The relevant bugs were fixed properly in: drm/radeon/kms: hopefully fix pll issues for real (v3) 5b40ddf888398ce4cccbf3b9d0a18d90149ed7ff drm/radeon/kms: add missing frac fb div flag for dce4+ 9f4283f49f0a96a64c5a45fe56f0f8c942885eef This commit also broke certain ~5 Mhz modes on old arcade monitors, so reverting this commit fixes: https://bugzilla.kernel.org/show_bug.cgi?id=29502 Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-02-15drm/radeon/kms: add bounds checking to avivo pll algoAlex Deucher
Prevent divider overflow. Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=28932 Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-02-02drm/radeon/kms: Enable new pll calculation for avivo+ asicsAlex Deucher
New algo is used for r5xx+ and legacy is used for r1xx-r4xx, rv515. I've tested on all relevant GPUs and monitors that I have access to and have found no problems. Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=26562 https://bugzilla.kernel.org/show_bug.cgi?id=26552 May fix: https://bugs.freedesktop.org/show_bug.cgi?id=32556 Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-02-02drm/radeon/kms: add new pll algo for avivo asicsAlex Deucher
Based on the vbios code. This should hopefully fix the pll problems on a number of avivo asics once it's enabled. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-02-02drm/radeon/kms: add pll debugging outputAlex Deucher
Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-02-02drm/radeon/kms: switch back to min->max pll post divider iterationAlex Deucher
Seems more reliable. Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=26552 Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-01-07drm/radeon/kms: add support for DCE5 display LUTsAlex Deucher
The hardware supports advanced user defined color management but at the moment, there is no infrastructure in place to take advantage of it so for now we just support the legacy LUTs. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-01-07drm/radeon/kms: DCE5 supports 16k display surfacesAlex Deucher
Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-12-21drm/radeon/kms: parse the extended LCD info blockAlex Deucher
This block may contain various additional LCD info such as physical size and a stored EDID. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-12-03Merge branch 'drm-radeon-fusion' of ../drm-radeon-next into drm-core-nextDave Airlie
* 'drm-radeon-fusion' of ../drm-radeon-next: drm/radeon/kms: add Ontario APU ucode loading support drm/radeon/kms: add Ontario Fusion APU pci ids drm/radeon/kms: enable MSIs on fusion APUs drm/radeon/kms: add power table parsing support for Ontario fusion APUs drm/radeon/kms: refactor atombios power state fetching drm/radeon/kms: add bo blit support for Ontario fusion APUs drm/radeon/kms: add thermal sensor support for fusion APUs drm/radeon/kms: fill in GPU init for AMD Ontario Fusion APUs drm/radeon/kms: add radeon_asic struct for AMD Ontario fusion APUs drm/radeon/kms: evergreen.c updates for fusion drm/radeon/kms: MC setup changes for fusion APUs drm/radeon/kms: move r7xx/evergreen to its own vram_gtt setup function drm/radeon/kms: add support for ss overrides on Fusion APUs drm/radeon/kms: Add support for external encoders on fusion APUs drm/radeon/kms: atom changes for DCE4.1 devices drm/radeon/kms: add new family id for AMD Ontario APUs drm/radeon/kms: upstream power table updates drm/radeon/kms: upstream atombios.h updates drm/radeon/kms: upstream ObjectID.h updates drm/radeon/kms: setup mc chremap properly on r7xx/evergreen
2010-11-23drm/radeon/kms: Add support for external encoders on fusion APUsAlex Deucher
Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-11-22drm/kms/radeon: Use high precision timestamps for pageflip completion events.Mario Kleiner
Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de> Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-11-22drm/radeon/kms: add pageflip ioctl support (v3)Alex Deucher
This adds support for dri2 pageflipping. v2: precision updates from Mario Kleiner. v3: Multihead fixes from Mario Kleiner; missing crtc offset add note about update pending bit on pre-avivo chips Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-11-22drm/kms/radeon: Add support for precise vblank timestamping.Mario Kleiner
This patch adds new functions for use by the drm core: .get_vblank_timestamp() provides a precise timestamp for the end of the most recent (or current) vblank interval of a given crtc, as needed for the DRI2 implementation of the OML_sync_control extension. It is a thin wrapper around the drm function drm_calc_vbltimestamp_from_scanoutpos() which does almost all the work and is shared across drivers. .get_scanout_position() provides the current horizontal and vertical video scanout position and "in vblank" status of a given crtc, as needed by the drm for use by drm_calc_vbltimestamp_from_scanoutpos(). The function is also used by the dynamic gpu reclocking code to determine when it is safe to reclock inside vblank. For that purpose radeon_pm_in_vbl() is modified to accomodate a small change in the function prototype of the radeon_get_crtc_scanoutpos() which is hooked up to .get_scanout_position(). This code has been tested on AVIVO hardware, a RV530 (ATI Mobility Radeon X1600) in a Intel Core-2 Duo MacBookPro and some R600 variant (FireGL V7600) in a single cpu AMD Athlon 64 PC. Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de> Reviewed-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-11-09drm/radeon/kms: add support for clock/data path routersAlex Deucher
This is a follow on to: 26b5bc986423cf3887e09188cb662ed651c5374d (drm/radeon/kms: add support for router objects) That patch added support for systems that use a mux to control the ddc line routing between the connectors. This patch adds support for systems that use a mux to control the encoder clock and data path routing to the connectors. Should fix: https://bugs.freedesktop.org/show_bug.cgi?id=31339 Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-19Revert "radeon, kdb, kms: Save and restore the LUT on atomic KMS enter/exit"Jason Wessel
This reverts commit ff773714dd30b802c336064109c535d8b2774e2f. A generic solution is needed to save and retore the LUT information. CC: Jesse Barnes <jbarnes@virtuousgeek.org> CC: dri-devel@lists.freedesktop.org Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-19Revert "drm/radeon/kms: remove some pll algo flags"Dave Airlie
This reverts commit f28488c282d8916b9b6190cc41714815bbaf97d5. On my rv610 test machine the monitor failed to light up after this. Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-06Merge branch 'drm-radeon-next' of ../drm-radeon-next into drm-core-nextDave Airlie
* 'drm-radeon-next' of ../drm-radeon-next: drm/radeon/kms: add drm blit support for evergreen drm/radeon: Modify radeon_pm_in_vbl to use radeon_get_crtc_scanoutpos() drm/radeon: Add function for display scanout position query. drm/radeon/kms: rework spread spectrum handling drm/radeon/kms: remove new pll algo drm/radeon/kms: remove some pll algo flags drm/radeon/kms: prefer high post dividers in legacy pll algo drm/radeon/kms: properly handle 40 bit MC addresses in the cursor code drm/radeon: add properties to configure the width of the underscan borders drm/radeon/kms/r6xx+: use new style fencing (v3) drm/radeon/kms: enable writeback (v2) drm/radeon/kms: clean up r6xx/r7xx blit init (v2)
2010-10-06radeon, kdb, kms: Save and restore the LUT on atomic KMS enter/exitJason Wessel
When changing VTs non-atomically the kernel works in conjunction with the Xserver in user space and receives the LUT information from the Xserver via a system call. When changing modes atomically for kdb, this information must be saved and restored without disturbing user space as if nothing ever happened. Signed-off-by: Jason Wessel <jason.wessel@windriver.com> CC: Jesse Barnes <jbarnes@virtuousgeek.org> CC: David Airlie <airlied@linux.ie> CC: dri-devel@lists.freedesktop.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-06drm/radeon: Add function for display scanout position query.Mario Kleiner
radeon_get_crtc_scanoutpos() returns the current horizontal and vertical scanout position of a crtc. It also reports if the display scanout is currently inside the vblank area. hpos reports current horizontal pixel scanout position. vpos reports the current scanned out line as a value >= 0 in active scanout. If the scanout is inside vblank area, it reports a negative value, the number of scanlines until end of vblank aka start of active scanout, e.g., -3 == "At most 3 scanlines until end of vblank". This code is derived from radeon_pm_in_vbl(), tested on R500 and R600. Signed-off-by: Mario Kleiner <mario.kleiner@tuebingen.mpg.de> Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-06drm/radeon/kms: remove new pll algoAlex Deucher
The recent changes to the old algo (prefer high post div) coupled with the range and precision limitations of using fixed point with the new algo make the new algo less useful. So drop the new algo. This should work as well or better than the old new/old combinations and simplifies the code a lot. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=30218 among others. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-06drm/radeon/kms: remove some pll algo flagsAlex Deucher
These shouldn't be needed with the post div changes in the last patch. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-06drm/radeon/kms: prefer high post dividers in legacy pll algoAlex Deucher
the hw prefers higher post dividers Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-06drm/radeon: add properties to configure the width of the underscan bordersMarius Gröger
This allows for a more exact fitting on the physical display. The new properties default to zero which corresponds to the previous underscan border width[height] formula: (display_width[display_width] >> 5) + 16. Example to set a horizontal border width of 30 and a vertikal border height of 22: xrandr --output HDMI-0 --set underscan on --set "underscan hborder" 30 --set "underscan vborder" 22 Signed-off-by: Marius Gröger <marius.groeger@googlemail.com> Reviewed-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-10-01drm/gem: handlecount isn't really a kref so don't make it one.Dave Airlie
There were lots of places being inconsistent since handle count looked like a kref but it really wasn't. Fix this my just making handle count an atomic on the object, and have it increase the normal object kref. Now i915/radeon/nouveau drivers can drop the normal reference on userspace object creation, and have the handle hold it. This patch fixes a memory leak or corruption on unload, because the driver had no way of knowing if a handle had been actually added for this object, and the fbcon object needed to know this to clean itself up properly. Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-27drm/radeon/kms: fix up encoder info messages for DFP6Alex Deucher
encoder info was not printed properly on boards using the DFP6 id. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-13drm/radeon/kms: don't enable underscan with interlaced modesAlex Deucher
They aren't compatible. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-09-13drm/radeon/kms: fix regression in RMX code (v2)Alex Deucher
caused by d65d65b175a29bd7ea2bb69c046419329c4a5db7 need to update the radeon crtc priv native mode before using it. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=30049 v2: integrate v/h copy paste typo Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-08-23drm/radeon/kms: try to detect tv vs monitor for underscanAlex Deucher
When enabling underscan for hdmi monitors, attempt to detect whether we are driving a TV or a monitor. The should hopefully prevent underscan from being enabled on monitors attached via hdmi that do not overscan the image. Only enable underscan if the mode is a common hdtv mode (480p, 720p, etc.). Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-08-10drm: expand gamma_setJames Simmons
Expand the crtc_gamma_set function to accept a starting offset. The reason for this is to eventually use this function for setcolreg from drm_fb_helper.c. The fbdev colormap function can start at any offset in the color map. Signed-by: James Simmons <jsimmons@infradead.org> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-08-10drm: Propagate error code from fb_create()Chris Wilson
Change the interface to expect a PTR_ERR specifing the real error code as opposed to assuming a NULL return => -EINVAL. Just once the user may not be at fault! Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-08-10drm/radeon/kms: add support for router objectsAlex Deucher
router objects are found on systems that use a mux to control ddc line to connector routing or to control the actual clock and data routing from the chip to the connectors. This patch implements ddc line routing. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-08-10drm/radeon/kms: unify i2c handlingAlex Deucher
Previously we added i2c buses as needed when enumerating connectors power management, etc. This only exposed the actual buses used and could have lead to the same buse getting created more than once if one buses was used for more than one purpose. This patch sets up all i2c buses on the card in one place and users of the buses just point back to the one instance. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-08-04drm/radeon/kms: enable underscan option for digital connectorsAlex Deucher
This connector attribute allows you to enable or disable underscan on a digital output to compensate for panels that automatically overscan (e.g., many HDMI TVs). Valid values for the attribute are: off - forces underscan off on - forces underscan on auto - enables underscan if an HDMI TV is connected, off otherwise default value is auto. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-08-04drm/radeon/kms: fix calculation of h/v scaling factorsAlex Deucher
Prior to this patch the code was dividing the src_v by the dst_h and vice versa, rather than src_v/dst_v and src_h/dst_h. This could lead to problems in the calculation of the display watermarks. Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-08-02drm/radeon/kms: move a bunch of modesetting debug to correct debug usage.Dave Airlie
This migrates a bunch of DRM_DEBUG->DRM_DEBUG_KMS so we can get more modesetting related info without all the other ioctl handling easily. Also the PM code moves to DRM_DEBUG_DRIVER mostly. Signed-off-by: Dave Airlie <airlied@redhat.com>
2010-08-02drm: radeon: fix sign bugDan Carpenter
The "error" variable is unsigned so it's never less than zero. I changed it to check if (freq < current_freq) directly. "best_error" is also unsigned so "best_error - 100" could be a large number instead of a negative. Since "error" is unsigned it is never less than a negative and so the cases where "best_error" is less than or equal to 100 are false. Signed-off-by: Dan Carpenter <error27@gmail.com> Reviewed-by: Alex Deucher <alexdeucher@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com>