[PATCH 2/2] regulator: uniphier: add regulator driver for UniPhier SoC

[Kunihiko Hayashi]

Initial commit to add support for regulators implemented in UniPhier SoCs.
This supports USB VBUS only.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
---
 drivers/regulator/Kconfig              |   8 ++
 drivers/regulator/Makefile             |   1 +
 drivers/regulator/uniphier-regulator.c | 251 +++++++++++++++++++++++++++++++++
 3 files changed, 260 insertions(+)
 create mode 100644 drivers/regulator/uniphier-regulator.c

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 097f617..7f7ad0d 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -932,6 +932,14 @@ config REGULATOR_TWL4030
 	  This driver supports the voltage regulators provided by
 	  this family of companion chips.
 
+config REGULATOR_UNIPHIER
+	tristate "UniPhier regulator driver"
+	depends on ARCH_UNIPHIER || COMPILE_TEST
+	depends on OF && MFD_SYSCON
+	default ARCH_UNIPHIER
+	help
+	  Support for regulators implemented on Socionext UniPhier SoCs.
+
 config REGULATOR_VCTRL
 	tristate "Voltage controlled regulators"
 	depends on OF
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index 590674f..c0dd281 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -116,6 +116,7 @@ obj-$(CONFIG_REGULATOR_TPS65912) += tps65912-regulator.o
 obj-$(CONFIG_REGULATOR_TPS80031) += tps80031-regulator.o
 obj-$(CONFIG_REGULATOR_TPS65132) += tps65132-regulator.o
 obj-$(CONFIG_REGULATOR_TWL4030) += twl-regulator.o twl6030-regulator.o
+obj-$(CONFIG_REGULATOR_UNIPHIER) += uniphier-regulator.o
 obj-$(CONFIG_REGULATOR_VCTRL) += vctrl-regulator.o
 obj-$(CONFIG_REGULATOR_VEXPRESS) += vexpress-regulator.o
 obj-$(CONFIG_REGULATOR_WM831X) += wm831x-dcdc.o
diff --git a/drivers/regulator/uniphier-regulator.c b/drivers/regulator/uniphier-regulator.c
new file mode 100644
index 0000000..b1f2649
--- /dev/null
+++ b/drivers/regulator/uniphier-regulator.c
@@ -0,0 +1,251 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Regulator controller driver for UniPhier SoC
+ * Copyright 2018 Socionext Inc.
+ * Author: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/of_regulator.h>
+#include <linux/reset.h>
+
+#define MAX_CLKS	2
+#define MAX_RSTS	2
+
+struct uniphier_regulator_soc_data {
+	const char *clock_names[MAX_CLKS];
+	const char *reset_names[MAX_RSTS];
+	const struct regulator_desc *desc;
+};
+
+struct uniphier_regulator_priv {
+	void __iomem *base;
+	int nclks;
+	struct clk *clk[MAX_CLKS];
+	int nrsts;
+	struct reset_control *rst[MAX_RSTS];
+	const struct uniphier_regulator_soc_data *data;
+};
+
+static int uniphier_regulator_enable(struct regulator_dev *rdev)
+{
+	struct uniphier_regulator_priv *priv = rdev_get_drvdata(rdev);
+	u32 val;
+
+	val = readl_relaxed(priv->base + rdev->desc->enable_reg);
+	val &= ~rdev->desc->enable_mask;
+	val |= rdev->desc->enable_val;
+	writel_relaxed(val, priv->base + rdev->desc->enable_reg);
+
+	return 0;
+}
+
+static int uniphier_regulator_disable(struct regulator_dev *rdev)
+{
+	struct uniphier_regulator_priv *priv = rdev_get_drvdata(rdev);
+	u32 val;
+
+	val = readl_relaxed(priv->base + rdev->desc->enable_reg);
+	val &= ~rdev->desc->enable_mask;
+	val |= rdev->desc->disable_val;
+	writel_relaxed(val, priv->base + rdev->desc->enable_reg);
+
+	return 0;
+}
+
+static int uniphier_regulator_is_enabled(struct regulator_dev *rdev)
+{
+	struct uniphier_regulator_priv *priv = rdev_get_drvdata(rdev);
+	u32 val;
+	int ret = -EINVAL;
+
+	val = readl(priv->base + rdev->desc->enable_reg);
+	val &= rdev->desc->enable_mask;
+
+	if (val == rdev->desc->enable_val)
+		ret = 1;
+	else if (val == rdev->desc->disable_val)
+		ret = 0;
+
+	return ret;
+}
+
+static struct regulator_ops uniphier_regulator_ops = {
+	.enable     = uniphier_regulator_enable,
+	.disable    = uniphier_regulator_disable,
+	.is_enabled = uniphier_regulator_is_enabled,
+};
+
+static int uniphier_regulator_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct uniphier_regulator_priv *priv;
+	struct regulator_config config = { };
+	struct regulator_dev *rdev;
+	struct resource *res;
+	const char *name;
+	int i, ret, nc, nr;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->data = of_device_get_match_data(dev);
+	if (WARN_ON(!priv->data))
+		return -EINVAL;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	for (i = 0; i < MAX_CLKS; i++) {
+		name = priv->data->clock_names[i];
+		if (!name)
+			break;
+		priv->clk[i] = devm_clk_get(dev, name);
+		if (IS_ERR(priv->clk[i]))
+			return PTR_ERR(priv->clk[i]);
+		priv->nclks++;
+	}
+
+	for (i = 0; i < MAX_RSTS; i++) {
+		name = priv->data->reset_names[i];
+		if (!name)
+			break;
+		priv->rst[i] = devm_reset_control_get_shared(dev, name);
+		if (IS_ERR(priv->rst[i]))
+			return PTR_ERR(priv->rst[i]);
+		priv->nrsts++;
+	}
+
+	for (nc = 0; nc < priv->nclks; nc++) {
+		ret = clk_prepare_enable(priv->clk[nc]);
+		if (ret)
+			goto out_clk_disable;
+	}
+
+	for (nr = 0; nr < priv->nrsts; nr++) {
+		ret = reset_control_deassert(priv->rst[nr]);
+		if (ret)
+			goto out_rst_assert;
+	}
+
+	/* Register UniPhier regulator */
+	config.dev = dev;
+	config.driver_data = priv;
+	config.of_node = dev->of_node;
+	config.init_data = of_get_regulator_init_data(dev, dev->of_node,
+						      priv->data->desc);
+	rdev = devm_regulator_register(dev, priv->data->desc, &config);
+	if (IS_ERR(rdev)) {
+		ret = PTR_ERR(rdev);
+		goto out_rst_assert;
+	}
+
+	platform_set_drvdata(pdev, priv);
+
+	return 0;
+
+out_rst_assert:
+	while (nr--)
+		reset_control_assert(priv->rst[nr]);
+out_clk_disable:
+	while (nc--)
+		clk_disable_unprepare(priv->clk[nc]);
+
+	return ret;
+}
+
+static int uniphier_regulator_remove(struct platform_device *pdev)
+{
+	struct uniphier_regulator_priv *priv = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < priv->nrsts; i++)
+		reset_control_assert(priv->rst[i]);
+	for (i = 0; i < priv->nclks; i++)
+		clk_disable_unprepare(priv->clk[i]);
+
+	return 0;
+}
+
+/* USB3 controller data */
+#define USB3VBUS_OFFSET		0x0
+#define USB3VBUS_REG		BIT(4)
+#define USB3VBUS_REG_EN		BIT(3)
+static const struct regulator_desc uniphier_usb3_regulator_desc = {
+	.name = "vbus",
+	.of_match = of_match_ptr("vbus"),
+	.ops = &uniphier_regulator_ops,
+	.type = REGULATOR_VOLTAGE,
+	.owner = THIS_MODULE,
+	.enable_reg  = USB3VBUS_OFFSET,
+	.enable_mask = USB3VBUS_REG_EN | USB3VBUS_REG,
+	.enable_val  = USB3VBUS_REG_EN | USB3VBUS_REG,
+	.disable_val = USB3VBUS_REG_EN,
+};
+
+static const struct uniphier_regulator_soc_data uniphier_pro4_usb3_data = {
+	.clock_names = { "gio", "link", },
+	.reset_names = { "gio", "link", },
+	.desc = &uniphier_usb3_regulator_desc,
+};
+
+static const struct uniphier_regulator_soc_data uniphier_pxs2_usb3_data = {
+	.clock_names = { "link", },
+	.reset_names = { "link", },
+	.desc = &uniphier_usb3_regulator_desc,
+};
+
+static const struct uniphier_regulator_soc_data uniphier_ld20_usb3_data = {
+	.clock_names = { "link", },
+	.reset_names = { "link", },
+	.desc = &uniphier_usb3_regulator_desc,
+};
+
+static const struct uniphier_regulator_soc_data uniphier_pxs3_usb3_data = {
+	.clock_names = { "link", },
+	.reset_names = { "link", },
+	.desc = &uniphier_usb3_regulator_desc,
+};
+
+static const struct of_device_id uniphier_regulator_match[] = {
+	/* USB VBUS */
+	{
+		.compatible = "socionext,uniphier-pro4-usb3-regulator",
+		.data = &uniphier_pro4_usb3_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs2-usb3-regulator",
+		.data = &uniphier_pxs2_usb3_data,
+	},
+	{
+		.compatible = "socionext,uniphier-ld20-usb3-regulator",
+		.data = &uniphier_ld20_usb3_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs3-usb3-regulator",
+		.data = &uniphier_pxs3_usb3_data,
+	},
+	{ /* Sentinel */ },
+};
+
+static struct platform_driver uniphier_regulator_driver = {
+	.probe = uniphier_regulator_probe,
+	.remove = uniphier_regulator_remove,
+	.driver = {
+		.name  = "uniphier-regulator",
+		.of_match_table = uniphier_regulator_match,
+	},
+};
+module_platform_driver(uniphier_regulator_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("UniPhier Regulator Controller Driver");
+MODULE_LICENSE("GPL");
-- 
2.7.4