clk: samsung: Add a separate driver for Exynos4412 ISP clocks

Some registers for the Exynos 4412 ISP (Camera subsystem) clocks are
located in the ISP power domain. Because those registers are also
located in a different memory region than the main clock controller,
support for them can be provided by a separate clock controller.
This in turn allows to almost seamlessly make it aware of the power
domain using recently introduced runtime PM support for clocks.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

drivers/clk/samsung/Makefile

@@ -5,6 +5,7 @@
 obj-$(CONFIG_COMMON_CLK)	+= clk.o clk-pll.o clk-cpu.o
 obj-$(CONFIG_SOC_EXYNOS3250)	+= clk-exynos3250.o
 obj-$(CONFIG_ARCH_EXYNOS4)	+= clk-exynos4.o
+obj-$(CONFIG_ARCH_EXYNOS4)	+= clk-exynos4412-isp.o
 obj-$(CONFIG_SOC_EXYNOS5250)	+= clk-exynos5250.o
 obj-$(CONFIG_SOC_EXYNOS5260)	+= clk-exynos5260.o
 obj-$(CONFIG_SOC_EXYNOS5410)	+= clk-exynos5410.o

drivers/clk/samsung/clk-exynos4412-isp.c

+/*
+ * Copyright (c) 2017 Samsung Electronics Co., Ltd.
+ * Author: Marek Szyprowski <m.szyprowski@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Common Clock Framework support for Exynos4412 ISP module.
+*/
+
+#include <dt-bindings/clock/exynos4.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include "clk.h"
+
+/* Exynos4x12 specific registers, which belong to ISP power domain */
+#define E4X12_DIV_ISP0		0x0300
+#define E4X12_DIV_ISP1		0x0304
+#define E4X12_GATE_ISP0		0x0800
+#define E4X12_GATE_ISP1		0x0804
+
+/*
+ * Support for CMU save/restore across system suspends
+ */
+static struct samsung_clk_reg_dump *exynos4x12_save_isp;
+
+static const unsigned long exynos4x12_clk_isp_save[] __initconst = {
+	E4X12_DIV_ISP0,
+	E4X12_DIV_ISP1,
+	E4X12_GATE_ISP0,
+	E4X12_GATE_ISP1,
+};
+
+PNAME(mout_user_aclk400_mcuisp_p4x12) = { "fin_pll", "div_aclk400_mcuisp", };
+
+static struct samsung_div_clock exynos4x12_isp_div_clks[] = {
+	DIV(CLK_ISP_DIV_ISP0, "div_isp0", "aclk200", E4X12_DIV_ISP0, 0, 3),
+	DIV(CLK_ISP_DIV_ISP1, "div_isp1", "aclk200", E4X12_DIV_ISP0, 4, 3),
+	DIV(CLK_ISP_DIV_MCUISP0, "div_mcuisp0", "aclk400_mcuisp",
+	    E4X12_DIV_ISP1, 4, 3),
+	DIV(CLK_ISP_DIV_MCUISP1, "div_mcuisp1", "div_mcuisp0",
+	    E4X12_DIV_ISP1, 8, 3),
+	DIV(0, "div_mpwm", "div_isp1", E4X12_DIV_ISP1, 0, 3),
+};
+
+static struct samsung_gate_clock exynos4x12_isp_gate_clks[] = {
+	GATE(CLK_ISP_FIMC_ISP, "isp", "aclk200", E4X12_GATE_ISP0, 0, 0, 0),
+	GATE(CLK_ISP_FIMC_DRC, "drc", "aclk200", E4X12_GATE_ISP0, 1, 0, 0),
+	GATE(CLK_ISP_FIMC_FD, "fd", "aclk200", E4X12_GATE_ISP0, 2, 0, 0),
+	GATE(CLK_ISP_FIMC_LITE0, "lite0", "aclk200", E4X12_GATE_ISP0, 3, 0, 0),
+	GATE(CLK_ISP_FIMC_LITE1, "lite1", "aclk200", E4X12_GATE_ISP0, 4, 0, 0),
+	GATE(CLK_ISP_MCUISP, "mcuisp", "aclk200", E4X12_GATE_ISP0, 5, 0, 0),
+	GATE(CLK_ISP_GICISP, "gicisp", "aclk200", E4X12_GATE_ISP0, 7, 0, 0),
+	GATE(CLK_ISP_SMMU_ISP, "smmu_isp", "aclk200", E4X12_GATE_ISP0, 8, 0, 0),
+	GATE(CLK_ISP_SMMU_DRC, "smmu_drc", "aclk200", E4X12_GATE_ISP0, 9, 0, 0),
+	GATE(CLK_ISP_SMMU_FD, "smmu_fd", "aclk200", E4X12_GATE_ISP0, 10, 0, 0),
+	GATE(CLK_ISP_SMMU_LITE0, "smmu_lite0", "aclk200", E4X12_GATE_ISP0, 11,
+	     0, 0),
+	GATE(CLK_ISP_SMMU_LITE1, "smmu_lite1", "aclk200", E4X12_GATE_ISP0, 12,
+	     0, 0),
+	GATE(CLK_ISP_PPMUISPMX, "ppmuispmx", "aclk200", E4X12_GATE_ISP0, 20,
+	     0, 0),
+	GATE(CLK_ISP_PPMUISPX, "ppmuispx", "aclk200", E4X12_GATE_ISP0, 21,
+	     0, 0),
+	GATE(CLK_ISP_MCUCTL_ISP, "mcuctl_isp", "aclk200", E4X12_GATE_ISP0, 23,
+	     0, 0),
+	GATE(CLK_ISP_MPWM_ISP, "mpwm_isp", "aclk200", E4X12_GATE_ISP0, 24,
+	     0, 0),
+	GATE(CLK_ISP_I2C0_ISP, "i2c0_isp", "aclk200", E4X12_GATE_ISP0, 25,
+	     0, 0),
+	GATE(CLK_ISP_I2C1_ISP, "i2c1_isp", "aclk200", E4X12_GATE_ISP0, 26,
+	     0, 0),
+	GATE(CLK_ISP_MTCADC_ISP, "mtcadc_isp", "aclk200", E4X12_GATE_ISP0, 27,
+	     0, 0),
+	GATE(CLK_ISP_PWM_ISP, "pwm_isp", "aclk200", E4X12_GATE_ISP0, 28, 0, 0),
+	GATE(CLK_ISP_WDT_ISP, "wdt_isp", "aclk200", E4X12_GATE_ISP0, 30, 0, 0),
+	GATE(CLK_ISP_UART_ISP, "uart_isp", "aclk200", E4X12_GATE_ISP0, 31,
+	     0, 0),
+	GATE(CLK_ISP_ASYNCAXIM, "asyncaxim", "aclk200", E4X12_GATE_ISP1, 0,
+	     0, 0),
+	GATE(CLK_ISP_SMMU_ISPCX, "smmu_ispcx", "aclk200", E4X12_GATE_ISP1, 4,
+	     0, 0),
+	GATE(CLK_ISP_SPI0_ISP, "spi0_isp", "aclk200", E4X12_GATE_ISP1, 12,
+	     0, 0),
+	GATE(CLK_ISP_SPI1_ISP, "spi1_isp", "aclk200", E4X12_GATE_ISP1, 13,
+	     0, 0),
+};
+
+static int __maybe_unused exynos4x12_isp_clk_suspend(struct device *dev)
+{
+	struct samsung_clk_provider *ctx = dev_get_drvdata(dev);
+
+	samsung_clk_save(ctx->reg_base, exynos4x12_save_isp,
+			 ARRAY_SIZE(exynos4x12_clk_isp_save));
+	return 0;
+}
+
+static int __maybe_unused exynos4x12_isp_clk_resume(struct device *dev)
+{
+	struct samsung_clk_provider *ctx = dev_get_drvdata(dev);
+
+	samsung_clk_restore(ctx->reg_base, exynos4x12_save_isp,
+			    ARRAY_SIZE(exynos4x12_clk_isp_save));
+	return 0;
+}
+
+static int __init exynos4x12_isp_clk_probe(struct platform_device *pdev)
+{
+	struct samsung_clk_provider *ctx;
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	struct resource *res;
+	void __iomem *reg_base;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	reg_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(reg_base)) {
+		dev_err(dev, "failed to map registers\n");
+		return PTR_ERR(reg_base);
+	}
+
+	exynos4x12_save_isp = samsung_clk_alloc_reg_dump(exynos4x12_clk_isp_save,
+					ARRAY_SIZE(exynos4x12_clk_isp_save));
+	if (!exynos4x12_save_isp)
+		return -ENOMEM;
+
+	ctx = samsung_clk_init(np, reg_base, CLK_NR_ISP_CLKS);
+	ctx->dev = dev;
+
+	platform_set_drvdata(pdev, ctx);
+
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	pm_runtime_get_sync(dev);
+
+	samsung_clk_register_div(ctx, exynos4x12_isp_div_clks,
+				 ARRAY_SIZE(exynos4x12_isp_div_clks));
+	samsung_clk_register_gate(ctx, exynos4x12_isp_gate_clks,
+				  ARRAY_SIZE(exynos4x12_isp_gate_clks));
+
+	samsung_clk_of_add_provider(np, ctx);
+	pm_runtime_put(dev);
+
+	return 0;
+}
+
+static const struct of_device_id exynos4x12_isp_clk_of_match[] = {
+	{ .compatible = "samsung,exynos4412-isp-clock", },
+	{ },
+};
+
+static const struct dev_pm_ops exynos4x12_isp_pm_ops = {
+	SET_RUNTIME_PM_OPS(exynos4x12_isp_clk_suspend,
+			   exynos4x12_isp_clk_resume, NULL)
+	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				     pm_runtime_force_resume)
+};
+
+static struct platform_driver exynos4x12_isp_clk_driver __refdata = {
+	.driver	= {
+		.name = "exynos4x12-isp-clk",
+		.of_match_table = exynos4x12_isp_clk_of_match,
+		.suppress_bind_attrs = true,
+		.pm = &exynos4x12_isp_pm_ops,
+	},
+	.probe = exynos4x12_isp_clk_probe,
+};
+
+static int __init exynos4x12_isp_clk_init(void)
+{
+	return platform_driver_register(&exynos4x12_isp_clk_driver);
+}
+core_initcall(exynos4x12_isp_clk_init);