On Friday 17 July 2015 18:38:59, Jianwei Wang wrote: > [...] > +static const struct regmap_config fsl_dcu_regmap_config = { > + .reg_bits = 32, > + .reg_stride = 4, > + .val_bits = 32, > +}; This defaults to REGCACHE_NONE which in the end sets regmap.cache_only = true. > [...] > +#ifdef CONFIG_PM_SLEEP > +static int fsl_dcu_drm_pm_suspend(struct device *dev) > +{ > + struct fsl_dcu_drm_device *fsl_dev = dev_get_drvdata(dev); > + > + if (!fsl_dev) > + return 0; > + > + drm_kms_helper_poll_disable(fsl_dev->drm); > + regcache_cache_only(fsl_dev->regmap, true); This should raise a warning (see http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/base/regmap/regcache.c#n472) as map->cache_bypass is set because of REGCACHE_NONE. I think you set the cache_type to REGCACHE_FLAT, but neither _LZO or _RBTREE (see https://lkml.org/lkml/2015/7/16/552 for that) Best regards, Alexander -- Dipl.-Inf. Alexander Stein SYS TEC electronic GmbH alexander.stein@xxxxxxxxxxxxxxxxxxxxx Legal and Commercial Address: Am Windrad 2 08468 Heinsdorfergrund Germany Office: +49 (0) 3765 38600-11xx Fax: +49 (0) 0) 3765 38600-41xx Managing Directors: Director Technology/CEO: Dipl.-Phys. Siegmar Schmidt; Director Commercial Affairs/COO: Dipl. Ing. (FH) Armin von Collrepp Commercial Registry: Amtsgericht Chemnitz, HRB 28082; USt.-Id Nr. DE150534010 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html