clk: max77686: Combine Maxim max77686 and max77802 driver

The clock IP used on the Maxim PMICs max77686 and max77802 are
same. The configuration of clock register is also same except
the number of clocks.

Part of common code utilisation, there is 3 files for these chips
clock driver, one for common and two files for driver registration.

Combine both drivers into single file and move common code into
same common file reduces the 2 files and make max77686 and max77802
clock driver in single fine. This driver does not depends on the
parent driver structure. The regmap handle is acquired through
regmap APIs for the register access.

This combination of driver helps on adding clock driver for different
Maxim PMICs which has similar clock IP like MAX77620 and MAX20024.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
CC: Krzysztof Kozlowski <k.kozlowski@samsung.com>
CC: Javier Martinez Canillas <javier@dowhile0.org>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

1 files changed, 232 insertions, 12 deletions

diff --git a/drivers/clk/clk-max77686.c b/drivers/clk/clk-max77686.c
index 9b6f2772e948..9aba3a8245e1 100644
--- a/drivers/clk/clk-max77686.c
+++ b/drivers/clk/clk-max77686.c
@@ -1,5 +1,5 @@
 /*
- * clk-max77686.c - Clock driver for Maxim 77686
+ * clk-max77686.c - Clock driver for Maxim 77686/MAX77802
  *
  * Copyright (C) 2012 Samsung Electornics
  * Jonghwa Lee <jonghwa3.lee@samsung.com>
@@ -30,41 +30,261 @@
 #include <linux/clk-provider.h>
 #include <linux/mutex.h>
 #include <linux/clkdev.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
 
 #include <dt-bindings/clock/maxim,max77686.h>
-#include "clk-max-gen.h"
+#include <dt-bindings/clock/maxim,max77802.h>
 
-static struct clk_init_data max77686_clks_init[MAX77686_CLKS_NUM] = {
+#define MAX77802_CLOCK_LOW_JITTER_SHIFT 0x3
+
+enum max77686_chip_name {
+	CHIP_MAX77686,
+	CHIP_MAX77802,
+};
+
+struct max77686_hw_clk_info {
+	const char *name;
+	u32 clk_reg;
+	u32 clk_enable_mask;
+	u32 flags;
+};
+
+struct max77686_clk_init_data {
+	struct regmap *regmap;
+	struct clk_hw hw;
+	struct clk_init_data clk_idata;
+	const struct max77686_hw_clk_info *clk_info;
+};
+
+struct max77686_clk_driver_data {
+	enum max77686_chip_name chip;
+	struct clk **clks;
+	struct max77686_clk_init_data *max_clk_data;
+	struct clk_onecell_data of_data;
+};
+
+static const struct
+max77686_hw_clk_info max77686_hw_clks_info[MAX77686_CLKS_NUM] = {
 	[MAX77686_CLK_AP] = {
 		.name = "32khz_ap",
-		.ops = &max_gen_clk_ops,
+		.clk_reg = MAX77686_REG_32KHZ,
+		.clk_enable_mask = BIT(MAX77686_CLK_AP),
 	},
 	[MAX77686_CLK_CP] = {
 		.name = "32khz_cp",
-		.ops = &max_gen_clk_ops,
+		.clk_reg = MAX77686_REG_32KHZ,
+		.clk_enable_mask = BIT(MAX77686_CLK_CP),
 	},
 	[MAX77686_CLK_PMIC] = {
 		.name = "32khz_pmic",
-		.ops = &max_gen_clk_ops,
+		.clk_reg = MAX77686_REG_32KHZ,
+		.clk_enable_mask = BIT(MAX77686_CLK_PMIC),
+	},
+};
+
+static const struct
+max77686_hw_clk_info max77802_hw_clks_info[MAX77802_CLKS_NUM] = {
+	[MAX77802_CLK_32K_AP] = {
+		.name = "32khz_ap",
+		.clk_reg = MAX77802_REG_32KHZ,
+		.clk_enable_mask = BIT(MAX77802_CLK_32K_AP),
+	},
+	[MAX77802_CLK_32K_CP] = {
+		.name = "32khz_cp",
+		.clk_reg = MAX77802_REG_32KHZ,
+		.clk_enable_mask = BIT(MAX77802_CLK_32K_CP),
 	},
 };
 
+static struct max77686_clk_init_data *to_max77686_clk_init_data(
+				struct clk_hw *hw)
+{
+	return container_of(hw, struct max77686_clk_init_data, hw);
+}
+
+static int max77686_clk_prepare(struct clk_hw *hw)
+{
+	struct max77686_clk_init_data *max77686 = to_max77686_clk_init_data(hw);
+
+	return regmap_update_bits(max77686->regmap, max77686->clk_info->clk_reg,
+				  max77686->clk_info->clk_enable_mask,
+				  max77686->clk_info->clk_enable_mask);
+}
+
+static void max77686_clk_unprepare(struct clk_hw *hw)
+{
+	struct max77686_clk_init_data *max77686 = to_max77686_clk_init_data(hw);
+
+	regmap_update_bits(max77686->regmap, max77686->clk_info->clk_reg,
+			   max77686->clk_info->clk_enable_mask,
+			   ~max77686->clk_info->clk_enable_mask);
+}
+
+static int max77686_clk_is_prepared(struct clk_hw *hw)
+{
+	struct max77686_clk_init_data *max77686 = to_max77686_clk_init_data(hw);
+	int ret;
+	u32 val;
+
+	ret = regmap_read(max77686->regmap, max77686->clk_info->clk_reg, &val);
+
+	if (ret < 0)
+		return -EINVAL;
+
+	return val & max77686->clk_info->clk_enable_mask;
+}
+
+static unsigned long max77686_recalc_rate(struct clk_hw *hw,
+					  unsigned long parent_rate)
+{
+	return 32768;
+}
+
+static struct clk_ops max77686_clk_ops = {
+	.prepare	= max77686_clk_prepare,
+	.unprepare	= max77686_clk_unprepare,
+	.is_prepared	= max77686_clk_is_prepared,
+	.recalc_rate	= max77686_recalc_rate,
+};
+
 static int max77686_clk_probe(struct platform_device *pdev)
 {
-	struct max77686_dev *iodev = dev_get_drvdata(pdev->dev.parent);
+	struct device *dev = &pdev->dev;
+	struct device *parent = dev->parent;
+	const struct platform_device_id *id = platform_get_device_id(pdev);
+	struct max77686_clk_driver_data *drv_data;
+	const struct max77686_hw_clk_info *hw_clks;
+	struct regmap *regmap;
+	int i, ret, num_clks;
+
+	drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
+	if (!drv_data)
+		return -ENOMEM;
+
+	regmap = dev_get_regmap(parent, NULL);
+	if (!regmap) {
+		dev_err(dev, "Failed to get rtc regmap\n");
+		return -ENODEV;
+	}
+
+	drv_data->chip = id->driver_data;
+
+	switch (drv_data->chip) {
+	case CHIP_MAX77686:
+		num_clks = MAX77686_CLKS_NUM;
+		hw_clks = max77686_hw_clks_info;
+		break;
+
+	case CHIP_MAX77802:
+		num_clks = MAX77802_CLKS_NUM;
+		hw_clks = max77802_hw_clks_info;
+		break;
+
+	default:
+		dev_err(dev, "Unknown Chip ID\n");
+		return -EINVAL;
+	}
+
+	drv_data->max_clk_data = devm_kcalloc(dev, num_clks,
+					      sizeof(*drv_data->max_clk_data),
+					      GFP_KERNEL);
+	if (!drv_data->max_clk_data)
+		return -ENOMEM;
+
+	drv_data->clks = devm_kcalloc(dev, num_clks,
+				      sizeof(*drv_data->clks), GFP_KERNEL);
+	if (!drv_data->clks)
+		return -ENOMEM;
 
-	return max_gen_clk_probe(pdev, iodev->regmap, MAX77686_REG_32KHZ,
-				 max77686_clks_init, MAX77686_CLKS_NUM);
+	for (i = 0; i < num_clks; i++) {
+		struct max77686_clk_init_data *max_clk_data;
+		struct clk *clk;
+		const char *clk_name;
+
+		max_clk_data = &drv_data->max_clk_data[i];
+
+		max_clk_data->regmap = regmap;
+		max_clk_data->clk_info = &hw_clks[i];
+		max_clk_data->clk_idata.flags = hw_clks[i].flags;
+		max_clk_data->clk_idata.ops = &max77686_clk_ops;
+
+		if (parent->of_node &&
+		    !of_property_read_string_index(parent->of_node,
+						   "clock-output-names",
+						   i, &clk_name))
+			max_clk_data->clk_idata.name = clk_name;
+		else
+			max_clk_data->clk_idata.name = hw_clks[i].name;
+
+		max_clk_data->hw.init = &max_clk_data->clk_idata;
+
+		clk = devm_clk_register(dev, &max_clk_data->hw);
+		if (IS_ERR(clk)) {
+			ret = PTR_ERR(clk);
+			dev_err(dev, "Failed to clock register: %d\n", ret);
+			return ret;
+		}
+
+		ret = clk_register_clkdev(clk, max_clk_data->clk_idata.name,
+					  NULL);
+		if (ret < 0) {
+			dev_err(dev, "Failed to clkdev register: %d\n", ret);
+			return ret;
+		}
+		drv_data->clks[i] = clk;
+	}
+
+	platform_set_drvdata(pdev, drv_data);
+
+	if (parent->of_node) {
+		drv_data->of_data.clks = drv_data->clks;
+		drv_data->of_data.clk_num = num_clks;
+		ret = of_clk_add_provider(parent->of_node,
+					  of_clk_src_onecell_get,
+					  &drv_data->of_data);
+
+		if (ret < 0) {
+			dev_err(dev, "Failed to register OF clock provider: %d\n",
+				ret);
+			return ret;
+		}
+	}
+
+	/* MAX77802: Enable low-jitter mode on the 32khz clocks. */
+	if (drv_data->chip == CHIP_MAX77802) {
+		ret = regmap_update_bits(regmap, MAX77802_REG_32KHZ,
+					 1 << MAX77802_CLOCK_LOW_JITTER_SHIFT,
+					 1 << MAX77802_CLOCK_LOW_JITTER_SHIFT);
+		if (ret < 0) {
+			dev_err(dev, "Failed to config low-jitter: %d\n", ret);
+			goto remove_of_clk_provider;
+		}
+	}
+
+	return 0;
+
+remove_of_clk_provider:
+	if (parent->of_node)
+		of_clk_del_provider(parent->of_node);
+
+	return ret;
 }
 
 static int max77686_clk_remove(struct platform_device *pdev)
 {
-	return max_gen_clk_remove(pdev, MAX77686_CLKS_NUM);
+	struct device *parent = pdev->dev.parent;
+
+	if (parent->of_node)
+		of_clk_del_provider(parent->of_node);
+
+	return 0;
 }
 
 static const struct platform_device_id max77686_clk_id[] = {
-	{ "max77686-clk", 0},
-	{ },
+	{ "max77686-clk", .driver_data = CHIP_MAX77686, },
+	{ "max77802-clk", .driver_data = CHIP_MAX77802, },
+	{},
 };
 MODULE_DEVICE_TABLE(platform, max77686_clk_id);