Re: [PATCH v2] drm: bridge: fsl-ldb: fixup mode on freq mismatch

From: kernel test robot
Date: Wed Dec 04 2024 - 07:50:12 EST


Hi Nikolaus,

kernel test robot noticed the following build warnings:

[auto build test WARNING on linus/master]
[also build test WARNING on drm-intel/for-linux-next drm-intel/for-linux-next-fixes drm-tip/drm-tip v6.13-rc1 next-20241203]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Nikolaus-Voss/drm-bridge-fsl-ldb-fixup-mode-on-freq-mismatch/20241204-115306
base: linus/master
patch link: https://lore.kernel.org/r/20241203191111.47B56F7%40mail.steuer-voss.de
patch subject: [PATCH v2] drm: bridge: fsl-ldb: fixup mode on freq mismatch
config: arm-randconfig-003-20241204 (https://download.01.org/0day-ci/archive/20241204/202412042024.4mJmO3sM-lkp@xxxxxxxxx/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241204/202412042024.4mJmO3sM-lkp@xxxxxxxxx/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202412042024.4mJmO3sM-lkp@xxxxxxxxx/

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/bridge/fsl-ldb.c:125:30: warning: omitting the parameter name in a function definition is a C2x extension [-Wc2x-extensions]
struct drm_bridge_state *,
^
drivers/gpu/drm/bridge/fsl-ldb.c:127:33: warning: omitting the parameter name in a function definition is a C2x extension [-Wc2x-extensions]
struct drm_connector_state *)
^
2 warnings generated.


vim +125 drivers/gpu/drm/bridge/fsl-ldb.c

123
124 static int fsl_ldb_atomic_check(struct drm_bridge *bridge,
> 125 struct drm_bridge_state *,
126 struct drm_crtc_state *crtc_state,
127 struct drm_connector_state *)
128 {
129 struct fsl_ldb *fsl_ldb = to_fsl_ldb(bridge);
130 const struct drm_display_mode *mode = &crtc_state->mode;
131 unsigned long requested_link_freq =
132 fsl_ldb_link_frequency(fsl_ldb, mode->clock);
133 unsigned long freq = clk_round_rate(fsl_ldb->clk, requested_link_freq);
134
135 if (freq != requested_link_freq) {
136 /*
137 * this will lead to flicker and incomplete lines on
138 * the attached display, adjust the CRTC clock
139 * accordingly.
140 */
141 struct drm_display_mode *adjusted_mode = &crtc_state->adjusted_mode;
142 int pclk = freq / fsl_ldb_link_frequency(fsl_ldb, 1);
143
144 if (adjusted_mode->clock != pclk) {
145 dev_warn(fsl_ldb->dev, "Adjusted pixel clk to match LDB clk (%d kHz -> %d kHz)!\n",
146 adjusted_mode->clock, pclk);
147
148 adjusted_mode->clock = pclk;
149 adjusted_mode->crtc_clock = pclk;
150 }
151 }
152
153 return 0;
154 }
155

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