[PATCH v10 1/5] drm/layerscape: Add Freescale DCU DRM driver

[alexander.stein@systec-electronic.com (Alexander Stein)]

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 at systec-electronic.com

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