[PATCH v1 04/12] usb: dwc3: dwc3-hisi: Add code for dwc3 of Hisilicon Soc Platform

[Yu Chen <chenyu56@huawei.com>]

This driver handles the poweron and shutdown of dwc3 core
on Hisilicon Soc Platform.

Cc: Felipe Balbi <balbi@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Binghui Wang <wangbinghui@hisilicon.com>
Signed-off-by: Yu Chen <chenyu56@huawei.com>
---
 MAINTAINERS                  |   8 ++
 drivers/usb/dwc3/Kconfig     |   8 ++
 drivers/usb/dwc3/Makefile    |   1 +
 drivers/usb/dwc3/dwc3-hisi.c | 335 +++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 352 insertions(+)
 create mode 100644 drivers/usb/dwc3/dwc3-hisi.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 6c3fbbb361f8..1b6b3026804c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -15465,6 +15465,14 @@ L:	linux-usb@vger.kernel.org
 S:	Maintained
 F:	drivers/usb/roles/intel-xhci-usb-role-switch.c
 
+USB IP DRIVER FOR HISILICON KIRIN
+M:	Yu Chen <chenyu56@huawei.com>
+M:	Binghui Wang <wangbinghui@hisilicon.com>
+L:	linux-usb@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/usb/dwc3-hisi.txt
+F:	drivers/usb/dwc3/dwc3-hisi.c
+
 USB ISP116X DRIVER
 M:	Olav Kongas <ok@artecdesign.ee>
 L:	linux-usb@vger.kernel.org
diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
index 1a0404fda596..09d105a2b53a 100644
--- a/drivers/usb/dwc3/Kconfig
+++ b/drivers/usb/dwc3/Kconfig
@@ -123,4 +123,12 @@ config USB_DWC3_QCOM
 	  for peripheral mode support.
 	  Say 'Y' or 'M' if you have one such device.
 
+config USB_DWC3_HISI
+	tristate "HiSilicon Kirin Platforms"
+	depends on ((ARCH_HISI && ARM64) || COMPILE_TEST) && OF
+	default USB_DWC3
+	help
+	  Support USB2/3 functionality in HiSilicon Kirin platforms.
+	  Say 'Y' or 'M' if you have one such device.
+
 endif
diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
index 6e3ef6144e5d..15781455e3f0 100644
--- a/drivers/usb/dwc3/Makefile
+++ b/drivers/usb/dwc3/Makefile
@@ -50,3 +50,4 @@ obj-$(CONFIG_USB_DWC3_KEYSTONE)		+= dwc3-keystone.o
 obj-$(CONFIG_USB_DWC3_OF_SIMPLE)	+= dwc3-of-simple.o
 obj-$(CONFIG_USB_DWC3_ST)		+= dwc3-st.o
 obj-$(CONFIG_USB_DWC3_QCOM)		+= dwc3-qcom.o
+obj-$(CONFIG_USB_DWC3_HISI)		+= dwc3-hisi.o
diff --git a/drivers/usb/dwc3/dwc3-hisi.c b/drivers/usb/dwc3/dwc3-hisi.c
new file mode 100644
index 000000000000..6e9787d420a7
--- /dev/null
+++ b/drivers/usb/dwc3/dwc3-hisi.c
@@ -0,0 +1,335 @@
+// SPDX-License-Identifier: GPL-2.0+
+/**
+ * dwc3-hisi.c - Support for dwc3 platform devices on HiSilicon platforms
+ *
+ * Copyright (C) 2017-2018 Hilisicon Electronics Co., Ltd.
+ *		http://www.huawei.com
+ *
+ * Authors: Yu Chen <chenyu56@huawei.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  of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/extcon.h>
+#include <linux/regulator/consumer.h>
+#include <linux/pinctrl/consumer.h>
+
+struct dwc3_hisi {
+	struct device		*dev;
+	struct clk		**clks;
+	int			num_clocks;
+	struct reset_control	**rstcs;
+	int			num_rstcs;
+};
+
+struct dwc3_hisi *g_dwc3_hisi;
+
+static int dwc3_hisi_init_clks(struct dwc3_hisi *dwc3_hisi,
+		struct device_node *np)
+{
+	struct device *dev = dwc3_hisi->dev;
+	int i;
+
+	dwc3_hisi->num_clocks = of_clk_get_parent_count(np);
+	if (!dwc3_hisi->num_clocks)
+		return -ENOENT;
+
+	dwc3_hisi->clks = devm_kcalloc(dev, dwc3_hisi->num_clocks,
+			sizeof(struct clk *), GFP_KERNEL);
+	if (!dwc3_hisi->clks)
+		return -ENOMEM;
+
+	for (i = 0; i < dwc3_hisi->num_clocks; i++) {
+		struct clk	*clk;
+
+		clk = of_clk_get(np, i);
+		if (IS_ERR(clk)) {
+			while (--i >= 0)
+				clk_put(dwc3_hisi->clks[i]);
+
+			return PTR_ERR(clk);
+		}
+
+		dwc3_hisi->clks[i] = clk;
+	}
+
+	return 0;
+}
+
+static int dwc3_hisi_enable_clks(struct dwc3_hisi *dwc3_hisi)
+{
+	int i;
+	int ret;
+
+	for (i = 0; i < dwc3_hisi->num_clocks; i++) {
+		ret = clk_prepare_enable(dwc3_hisi->clks[i]);
+		if (ret < 0) {
+			while (--i >= 0)
+				clk_disable_unprepare(dwc3_hisi->clks[i]);
+
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static void dwc3_hisi_disable_clks(struct dwc3_hisi *dwc3_hisi)
+{
+	int i;
+
+	for (i = 0; i < dwc3_hisi->num_clocks; i++)
+		clk_disable_unprepare(dwc3_hisi->clks[i]);
+}
+
+static int dwc3_hisi_get_rstcs(struct dwc3_hisi *dwc3_hisi,
+		struct device_node *np)
+{
+	struct device *dev = dwc3_hisi->dev;
+	int i;
+
+	dwc3_hisi->num_rstcs = of_count_phandle_with_args(np,
+			"resets", "#reset-cells");
+	if (!dwc3_hisi->num_rstcs)
+		return -ENOENT;
+
+	dwc3_hisi->rstcs = devm_kcalloc(dev, dwc3_hisi->num_rstcs,
+			sizeof(struct reset_control *), GFP_KERNEL);
+	if (!dwc3_hisi->rstcs)
+		return -ENOMEM;
+
+	for (i = 0; i < dwc3_hisi->num_rstcs; i++) {
+		struct reset_control *rstc;
+
+		rstc = of_reset_control_get_shared_by_index(np, i);
+		if (IS_ERR(rstc)) {
+			while (--i >= 0)
+				reset_control_put(dwc3_hisi->rstcs[i]);
+			return PTR_ERR(rstc);
+		}
+
+		dwc3_hisi->rstcs[i] = rstc;
+	}
+
+	return 0;
+}
+
+static int dwc3_hisi_reset_control_assert(struct dwc3_hisi *dwc3_hisi)
+{
+	int i, ret;
+
+	for (i = dwc3_hisi->num_rstcs - 1; i >= 0 ; i--) {
+		ret = reset_control_assert(dwc3_hisi->rstcs[i]);
+		if (ret) {
+			while (--i >= 0)
+				reset_control_deassert(dwc3_hisi->rstcs[i]);
+			return ret;
+		}
+		udelay(10);
+	}
+
+	return 0;
+}
+
+static int dwc3_hisi_reset_control_deassert(struct dwc3_hisi *dwc3_hisi)
+{
+	int i, ret;
+
+	for (i = 0; i < dwc3_hisi->num_rstcs; i++) {
+		ret = reset_control_deassert(dwc3_hisi->rstcs[i]);
+		if (ret) {
+			while (--i >= 0)
+				reset_control_assert(dwc3_hisi->rstcs[i]);
+			return ret;
+		}
+		udelay(10);
+	}
+
+	return 0;
+}
+
+static int dwc3_hisi_probe(struct platform_device *pdev)
+{
+	struct dwc3_hisi	*dwc3_hisi;
+	struct device		*dev = &pdev->dev;
+	struct device_node	*np = dev->of_node;
+
+	int			ret;
+	int			i;
+
+	dwc3_hisi = devm_kzalloc(dev, sizeof(*dwc3_hisi), GFP_KERNEL);
+	if (!dwc3_hisi)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, dwc3_hisi);
+	dwc3_hisi->dev = dev;
+
+	ret = dwc3_hisi_init_clks(dwc3_hisi, np);
+	if (ret) {
+		dev_err(dev, "could not get clocks\n");
+		return ret;
+	}
+
+	ret = dwc3_hisi_enable_clks(dwc3_hisi);
+	if (ret) {
+		dev_err(dev, "could not enable clocks\n");
+		goto err_put_clks;
+	}
+
+	ret = dwc3_hisi_get_rstcs(dwc3_hisi, np);
+	if (ret) {
+		dev_err(dev, "could not get reset controllers\n");
+		goto err_disable_clks;
+	}
+	ret = dwc3_hisi_reset_control_deassert(dwc3_hisi);
+	if (ret) {
+		dev_err(dev, "reset control deassert failed\n");
+		goto err_put_rstcs;
+	}
+
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	pm_runtime_get_sync(dev);
+
+	ret = of_platform_populate(np, NULL, NULL, dev);
+	if (ret) {
+		dev_err(dev, "failed to add dwc3 core\n");
+		goto err_reset_assert;
+	}
+
+	dev_err(dev, "finish dwc3 hisi probe\n");
+
+	g_dwc3_hisi = dwc3_hisi;
+	return 0;
+
+err_reset_assert:
+	ret = dwc3_hisi_reset_control_assert(dwc3_hisi);
+	if (ret)
+		dev_err(dev, "reset control assert failed\n");
+err_put_rstcs:
+	for (i = 0; i < dwc3_hisi->num_rstcs; i++)
+		reset_control_put(dwc3_hisi->rstcs[i]);
+err_disable_clks:
+	dwc3_hisi_disable_clks(dwc3_hisi);
+err_put_clks:
+	for (i = 0; i < dwc3_hisi->num_clocks; i++)
+		clk_put(dwc3_hisi->clks[i]);
+
+	return ret;
+}
+
+static int dwc3_hisi_remove(struct platform_device *pdev)
+{
+	struct dwc3_hisi	*dwc3_hisi = platform_get_drvdata(pdev);
+	struct device		*dev = &pdev->dev;
+	int			i, ret;
+
+	of_platform_depopulate(dev);
+
+	ret = dwc3_hisi_reset_control_assert(dwc3_hisi);
+	if (ret) {
+		dev_err(dev, "reset control assert failed\n");
+		return ret;
+	}
+
+	for (i = 0; i < dwc3_hisi->num_clocks; i++) {
+		clk_disable_unprepare(dwc3_hisi->clks[i]);
+		clk_put(dwc3_hisi->clks[i]);
+	}
+
+	pm_runtime_put_sync(dev);
+	pm_runtime_disable(dev);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int dwc3_hisi_suspend(struct device *dev)
+{
+	struct dwc3_hisi *dwc3_hisi = dev_get_drvdata(dev);
+	int ret;
+
+	dev_info(dev, "%s\n", __func__);
+
+	ret = dwc3_hisi_reset_control_assert(dwc3_hisi);
+	if (ret) {
+		dev_err(dev, "reset control assert failed\n");
+		return ret;
+	}
+
+	dwc3_hisi_disable_clks(dwc3_hisi);
+
+	pinctrl_pm_select_default_state(dev);
+
+	return 0;
+}
+
+static int dwc3_hisi_resume(struct device *dev)
+{
+	struct dwc3_hisi *dwc3_hisi = dev_get_drvdata(dev);
+	int ret;
+
+	dev_info(dev, "%s\n", __func__);
+	pinctrl_pm_select_default_state(dev);
+
+	ret = dwc3_hisi_enable_clks(dwc3_hisi);
+	if (ret) {
+		dev_err(dev, "could not enable clocks\n");
+		return ret;
+	}
+
+	ret = dwc3_hisi_reset_control_deassert(dwc3_hisi);
+	if (ret) {
+		dev_err(dev, "reset control deassert failed\n");
+		return ret;
+	}
+
+	/* Wait for clock stable */
+	msleep(100);
+
+	return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static SIMPLE_DEV_PM_OPS(dwc3_hisi_dev_pm_ops,
+		dwc3_hisi_suspend, dwc3_hisi_resume);
+
+static const struct of_device_id dwc3_hisi_match[] = {
+	{ .compatible = "hisilicon,hi3660-dwc3" },
+	{ /* sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(of, dwc3_hisi_match);
+
+static struct platform_driver dwc3_hisi_driver = {
+	.probe = dwc3_hisi_probe,
+	.remove = dwc3_hisi_remove,
+	.driver = {
+		.name = "usb-hisi-dwc3",
+		.of_match_table = dwc3_hisi_match,
+		.pm = &dwc3_hisi_dev_pm_ops,
+	},
+};
+
+module_platform_driver(dwc3_hisi_driver);
+
+MODULE_AUTHOR("Yu Chen <chenyu56@huawei.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("DesignWare USB3 HiSilicon Glue Layer");
-- 
2.15.0-rc2