usb: Add MediaTek USB3 DRD driver

This patch adds support for the MediaTek USB3 controller
integrated into MT8173. It currently supports High-Speed
Peripheral Only mode.

Super-Speed Peripheral, Dual-Role Device and Host Only (xHCI)
modes will be added in the next patchs.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 251 insertions, 0 deletions

diff --git a/drivers/usb/mtu3/mtu3_plat.c b/drivers/usb/mtu3/mtu3_plat.c
new file mode 100644
index 000000000000..52fc0edbe3ee
--- /dev/null
+++ b/drivers/usb/mtu3/mtu3_plat.c
@@ -0,0 +1,251 @@
+/*
+ * Copyright (C) 2016 MediaTek Inc.
+ *
+ * Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+
+#include "mtu3.h"
+
+/* u2-port0 should be powered on and enabled; */
+int ssusb_check_clocks(struct mtu3 *mtu, u32 ex_clks)
+{
+	void __iomem *ibase = mtu->ippc_base;
+	u32 value, check_val;
+	int ret;
+
+	check_val = ex_clks | SSUSB_SYS125_RST_B_STS | SSUSB_SYSPLL_STABLE |
+			SSUSB_REF_RST_B_STS;
+
+	ret = readl_poll_timeout(ibase + U3D_SSUSB_IP_PW_STS1, value,
+			(check_val == (value & check_val)), 100, 20000);
+	if (ret) {
+		dev_err(mtu->dev, "clks of sts1 are not stable!\n");
+		return ret;
+	}
+
+	ret = readl_poll_timeout(ibase + U3D_SSUSB_IP_PW_STS2, value,
+			(value & SSUSB_U2_MAC_SYS_RST_B_STS), 100, 10000);
+	if (ret) {
+		dev_err(mtu->dev, "mac2 clock is not stable\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int ssusb_rscs_init(struct mtu3 *mtu)
+{
+	int ret = 0;
+
+	ret = regulator_enable(mtu->vusb33);
+	if (ret) {
+		dev_err(mtu->dev, "failed to enable vusb33\n");
+		goto vusb33_err;
+	}
+
+	ret = clk_prepare_enable(mtu->sys_clk);
+	if (ret) {
+		dev_err(mtu->dev, "failed to enable sys_clk\n");
+		goto clk_err;
+	}
+
+	ret = phy_init(mtu->phy);
+	if (ret) {
+		dev_err(mtu->dev, "failed to init phy\n");
+		goto phy_init_err;
+	}
+
+	ret = phy_power_on(mtu->phy);
+	if (ret) {
+		dev_err(mtu->dev, "failed to power on phy\n");
+		goto phy_err;
+	}
+
+	return 0;
+
+phy_err:
+	phy_exit(mtu->phy);
+
+phy_init_err:
+	clk_disable_unprepare(mtu->sys_clk);
+
+clk_err:
+	regulator_disable(mtu->vusb33);
+
+vusb33_err:
+
+	return ret;
+}
+
+static void ssusb_rscs_exit(struct mtu3 *mtu)
+{
+	clk_disable_unprepare(mtu->sys_clk);
+	regulator_disable(mtu->vusb33);
+	phy_power_off(mtu->phy);
+	phy_exit(mtu->phy);
+}
+
+static void ssusb_ip_sw_reset(struct mtu3 *mtu)
+{
+	mtu3_setbits(mtu->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);
+	udelay(1);
+	mtu3_clrbits(mtu->ippc_base, U3D_SSUSB_IP_PW_CTRL0, SSUSB_IP_SW_RST);
+}
+
+static int get_ssusb_rscs(struct platform_device *pdev, struct mtu3 *mtu)
+{
+	struct device_node *node = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+
+	mtu->phy = devm_of_phy_get_by_index(dev, node, 0);
+	if (IS_ERR(mtu->phy)) {
+		dev_err(dev, "failed to get phy\n");
+		return PTR_ERR(mtu->phy);
+	}
+
+	mtu->irq = platform_get_irq(pdev, 0);
+	if (mtu->irq <= 0) {
+		dev_err(dev, "fail to get irq number\n");
+		return -ENODEV;
+	}
+	dev_info(dev, "irq %d\n", mtu->irq);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mac");
+	mtu->mac_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(mtu->mac_base)) {
+		dev_err(dev, "error mapping memory for dev mac\n");
+		return PTR_ERR(mtu->mac_base);
+	}
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ippc");
+	mtu->ippc_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(mtu->ippc_base)) {
+		dev_err(dev, "failed to map memory for ippc\n");
+		return PTR_ERR(mtu->ippc_base);
+	}
+
+	mtu->vusb33 = devm_regulator_get(&pdev->dev, "vusb33");
+	if (IS_ERR(mtu->vusb33)) {
+		dev_err(dev, "failed to get vusb33\n");
+		return PTR_ERR(mtu->vusb33);
+	}
+
+	mtu->sys_clk = devm_clk_get(dev, "sys_ck");
+	if (IS_ERR(mtu->sys_clk)) {
+		dev_err(dev, "failed to get sys clock\n");
+		return PTR_ERR(mtu->sys_clk);
+	}
+
+	return 0;
+}
+
+static int mtu3_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mtu3 *mtu;
+	int ret = -ENOMEM;
+
+	/* all elements are set to ZERO as default value */
+	mtu = devm_kzalloc(dev, sizeof(struct mtu3), GFP_KERNEL);
+	if (!mtu)
+		return -ENOMEM;
+
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+	if (ret) {
+		dev_err(dev, "No suitable DMA config available\n");
+		return -ENOTSUPP;
+	}
+
+	platform_set_drvdata(pdev, mtu);
+	mtu->dev = dev;
+	spin_lock_init(&mtu->lock);
+
+	ret = get_ssusb_rscs(pdev, mtu);
+	if (ret)
+		return ret;
+
+	/* enable power domain */
+	pm_runtime_enable(dev);
+	pm_runtime_get_sync(dev);
+	device_enable_async_suspend(dev);
+
+	ret = ssusb_rscs_init(mtu);
+	if (ret)
+		goto comm_init_err;
+
+	ssusb_ip_sw_reset(mtu);
+
+	ret = ssusb_gadget_init(mtu);
+	if (ret) {
+		dev_err(dev, "failed to initialize gadget\n");
+		goto comm_exit;
+	}
+
+	return 0;
+
+comm_exit:
+	ssusb_rscs_exit(mtu);
+
+comm_init_err:
+	pm_runtime_put_sync(dev);
+	pm_runtime_disable(dev);
+
+	return ret;
+}
+
+static int mtu3_remove(struct platform_device *pdev)
+{
+	struct mtu3 *mtu = platform_get_drvdata(pdev);
+
+	ssusb_gadget_exit(mtu);
+	ssusb_rscs_exit(mtu);
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+
+static const struct of_device_id mtu3_of_match[] = {
+	{.compatible = "mediatek,mt8173-mtu3",},
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, mtu3_of_match);
+
+#endif
+
+static struct platform_driver mtu3_driver = {
+	.probe = mtu3_probe,
+	.remove = mtu3_remove,
+	.driver = {
+		.name = MTU3_DRIVER_NAME,
+		.of_match_table = of_match_ptr(mtu3_of_match),
+	},
+};
+module_platform_driver(mtu3_driver);
+
+MODULE_AUTHOR("Chunfeng Yun <chunfeng.yun@mediatek.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MediaTek USB3 DRD Controller Driver");