clk: mediatek: Add MT8195 ccusys clock support

Add MT8195 ccusys clock controller which provides clock gate
control in Camera Computing Unit.

Signed-off-by: Chun-Jie Chen <chun-jie.chen@mediatek.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20210914021633.26377-12-chun-jie.chen@mediatek.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/mediatek/Makefile

@@ -82,6 +82,6 @@ obj-$(CONFIG_COMMON_CLK_MT8192_VDECSYS) += clk-mt8192-vdec.o
 obj-$(CONFIG_COMMON_CLK_MT8192_VENCSYS) += clk-mt8192-venc.o
 obj-$(CONFIG_COMMON_CLK_MT8195) += clk-mt8195-apmixedsys.o clk-mt8195-topckgen.o \
 				   clk-mt8195-peri_ao.o clk-mt8195-infra_ao.o \
-				   clk-mt8195-cam.o
+				   clk-mt8195-cam.o clk-mt8195-ccu.o
 obj-$(CONFIG_COMMON_CLK_MT8516) += clk-mt8516.o
 obj-$(CONFIG_COMMON_CLK_MT8516_AUDSYS) += clk-mt8516-aud.o

drivers/clk/mediatek/clk-mt8195-ccu.c

@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Copyright (c) 2021 MediaTek Inc.
+// Author: Chun-Jie Chen <chun-jie.chen@mediatek.com>
+
+#include "clk-gate.h"
+#include "clk-mtk.h"
+
+#include <dt-bindings/clock/mt8195-clk.h>
+#include <linux/clk-provider.h>
+#include <linux/platform_device.h>
+
+static const struct mtk_gate_regs ccu_cg_regs = {
+	.set_ofs = 0x4,
+	.clr_ofs = 0x8,
+	.sta_ofs = 0x0,
+};
+
+#define GATE_CCU(_id, _name, _parent, _shift)			\
+	GATE_MTK(_id, _name, _parent, &ccu_cg_regs, _shift, &mtk_clk_gate_ops_setclr)
+
+static const struct mtk_gate ccu_clks[] = {
+	GATE_CCU(CLK_CCU_LARB18, "ccu_larb18", "top_ccu", 0),
+	GATE_CCU(CLK_CCU_AHB, "ccu_ahb", "top_ccu", 1),
+	GATE_CCU(CLK_CCU_CCU0, "ccu_ccu0", "top_ccu", 2),
+	GATE_CCU(CLK_CCU_CCU1, "ccu_ccu1", "top_ccu", 3),
+};
+
+static const struct mtk_clk_desc ccu_desc = {
+	.clks = ccu_clks,
+	.num_clks = ARRAY_SIZE(ccu_clks),
+};
+
+static const struct of_device_id of_match_clk_mt8195_ccu[] = {
+	{
+		.compatible = "mediatek,mt8195-ccusys",
+		.data = &ccu_desc,
+	}, {
+		/* sentinel */
+	}
+};
+
+static struct platform_driver clk_mt8195_ccu_drv = {
+	.probe = mtk_clk_simple_probe,
+	.driver = {
+		.name = "clk-mt8195-ccu",
+		.of_match_table = of_match_clk_mt8195_ccu,
+	},
+};
+builtin_platform_driver(clk_mt8195_ccu_drv);