linux/drivers/gpu/drm/pl111/pl111_nomadik.c
Linus Walleij e08015e7d6 drm/pl111: Support Nomadik LCDC variant
The Nomadik has a variant of the PL110 known as "Color LCD
Controller" LCDC. This variant has the same bit ordering as
the DRM subsystem (in difference from the other variants)
and adds a few bits for the control of 5551, 565 etc in the
control register. Notably it also adds a packed RGB888
24BPP mode.

We add support by detecting this variant and also adding a
small plug-in that will mux the LCDC out if the ASIC happens
to be muxed to the other graphics controller (they are
mutually exclusive).

Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20180621184450.25377-1-linus.walleij@linaro.org
2018-07-01 21:36:47 +02:00

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C

// SPDX-License-Identifier: GPL-2.0+
#include <linux/device.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include "pl111_nomadik.h"
#define PMU_CTRL_OFFSET 0x0000
#define PMU_CTRL_LCDNDIF BIT(26)
void pl111_nomadik_init(struct device *dev)
{
struct regmap *pmu_regmap;
/*
* Just bail out of this is not found, we could be running
* multiplatform on something else than Nomadik.
*/
pmu_regmap =
syscon_regmap_lookup_by_compatible("stericsson,nomadik-pmu");
if (IS_ERR(pmu_regmap))
return;
/*
* This bit in the PMU controller multiplexes the two graphics
* blocks found in the Nomadik STn8815. The other one is called
* MDIF (Master Display Interface) and gets muxed out here.
*/
regmap_update_bits(pmu_regmap,
PMU_CTRL_OFFSET,
PMU_CTRL_LCDNDIF,
0);
dev_info(dev, "set Nomadik PMU mux to CLCD mode\n");
}
EXPORT_SYMBOL_GPL(pl111_nomadik_init);