[PATCH u-boot 1/3] usb: host: Add simple of glue driver for DWC3 USB Controllers integration

[narmstrong@baylibre.com (Neil Armstrong)]

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
---
 drivers/usb/host/Kconfig          |   7 ++
 drivers/usb/host/Makefile         |   1 +
 drivers/usb/host/dwc3-of-simple.c | 187 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 195 insertions(+)
 create mode 100644 drivers/usb/host/dwc3-of-simple.c

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index a7249b7..6caa615 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -21,6 +21,13 @@ config USB_XHCI_DWC3
 	  Say Y or if your system has a Dual Role SuperSpeed
 	  USB controller based on the DesignWare USB3 IP Core.
 
+config USB_XHCI_DWC3_OF_SIMPLE
+	bool "DesignWare USB3 DRD Generic OF Simple Glue Layer"
+	select MISC
+	help
+	  Support USB2/3 functionality in simple SoC integrations with
+	  USB controller based on the DesignWare USB3 IP Core.
+
 config USB_XHCI_MVEBU
 	bool "MVEBU USB 3.0 support"
 	default y
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index 9819489..abe4f90 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -49,6 +49,7 @@ obj-$(CONFIG_USB_EHCI_ZYNQ) += ehci-zynq.o
 # xhci
 obj-$(CONFIG_USB_XHCI_HCD) += xhci.o xhci-mem.o xhci-ring.o
 obj-$(CONFIG_USB_XHCI_DWC3) += xhci-dwc3.o
+obj-$(CONFIG_USB_XHCI_DWC3_OF_SIMPLE) += dwc3-of-simple.o
 obj-$(CONFIG_USB_XHCI_ROCKCHIP) += xhci-rockchip.o
 obj-$(CONFIG_USB_XHCI_ZYNQMP) += xhci-zynqmp.o
 obj-$(CONFIG_USB_XHCI_KEYSTONE) += xhci-keystone.o
diff --git a/drivers/usb/host/dwc3-of-simple.c b/drivers/usb/host/dwc3-of-simple.c
new file mode 100644
index 0000000..826a996
--- /dev/null
+++ b/drivers/usb/host/dwc3-of-simple.c
@@ -0,0 +1,187 @@
+/*
+ * dwc3-of-simple.c - OF glue layer for simple integrations
+ *
+ * Copyright (c) 2015 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * Author: Felipe Balbi <balbi@ti.com>
+ *
+ * Copyright (C) 2018 BayLibre, SAS
+ * Author: Neil Armstrong <narmstron@baylibre.com>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <fdtdec.h>
+#include <reset.h>
+#include <clk.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct dwc3_of_simple {
+#if CONFIG_IS_ENABLED(CLK)
+	struct clk		*clks;
+	int			num_clocks;
+#endif
+#if CONFIG_IS_ENABLED(DM_RESET)
+	struct reset_ctl	*resets;
+	int			num_resets;
+#endif
+};
+
+#if CONFIG_IS_ENABLED(DM_RESET)
+static int dwc3_of_simple_reset_init(struct udevice *dev,
+				     struct dwc3_of_simple *simple,
+				     int count)
+{
+	int i, ret, err;
+
+	if (!count)
+		return 0;
+
+	simple->resets = devm_kcalloc(dev, count, sizeof(struct reset_ctl),
+				      GFP_KERNEL);
+	if (!simple->resets)
+		return -ENOMEM;
+
+	for (i = 0; i < count; i++) {
+		ret = reset_get_by_index(dev, i, &simple->resets[i]);
+		if (ret < 0)
+			break;
+
+		ret = reset_request(&simple->resets[i]);
+		if (ret) {
+			pr_err("failed to request reset line %d\n", i);
+			reset_free(&simple->resets[i]);
+			goto reset_err;
+		}
+
+		
+		++simple->num_resets;
+	}
+
+	for (i = 0; i < simple->num_resets; i++) {
+		ret = reset_deassert(&simple->resets[i]);
+		if (ret && ret != -ENOSYS && ret != -ENOTSUPP) {
+			pr_err("failed to deassert reset line %d\n", i);
+			goto reset_err;
+		}
+	}
+
+	return 0;
+
+reset_err:
+	err = reset_release_all(simple->resets, simple->num_resets);
+	if (err)
+		pr_err("failed to disable all clocks\n");
+	
+	return ret;
+}
+#endif
+
+#if CONFIG_IS_ENABLED(CLK)
+static int dwc3_of_simple_clk_init(struct udevice *dev,
+				   struct dwc3_of_simple *simple,
+				   int count)
+{
+	int i, ret, err;
+
+	if (!count)
+		return 0;
+
+	simple->clks = devm_kcalloc(dev, count, sizeof(struct clk),
+				    GFP_KERNEL);
+	if (!simple->clks)
+		return -ENOMEM;
+
+	for (i = 0; i < count; i++) {
+		ret = clk_get_by_index(dev, i, &simple->clks[i]);
+		if (ret < 0)
+			break;
+
+		ret = clk_enable(&simple->clks[i]);
+		if (ret && ret != -ENOSYS && ret != -ENOTSUPP) {
+			pr_err("failed to enable clock %d\n", i);
+			clk_free(&simple->clks[i]);
+			goto clk_err;
+		}
+
+		++simple->num_clocks;
+	}
+
+	return 0;
+
+clk_err:
+	err = clk_release_all(simple->clks, simple->num_clocks);
+	if (err)
+		pr_err("failed to disable all clocks\n");
+	
+	return ret;
+}
+#endif
+
+static int dwc3_of_simple_probe(struct udevice *dev)
+{
+#if CONFIG_IS_ENABLED(DM_RESET) || CONFIG_IS_ENABLED(CLK)
+	struct dwc3_of_simple *simple = dev_get_platdata(dev);
+	int ret;
+#endif
+
+#if CONFIG_IS_ENABLED(CLK)
+	ret = dwc3_of_simple_clk_init(dev, simple,
+		dev_count_phandle_with_args(dev, "clocks", "#clock-cells"));
+	if (ret)
+		return ret;
+#endif
+
+#if CONFIG_IS_ENABLED(DM_RESET)
+	ret = dwc3_of_simple_reset_init(dev, simple,
+		dev_count_phandle_with_args(dev, "resets", "#reset-cells"));
+	if (ret)
+		return ret;
+#endif
+
+	return 0;
+}
+
+static int dwc3_of_simple_remove(struct udevice *dev)
+{
+#if CONFIG_IS_ENABLED(DM_RESET) || CONFIG_IS_ENABLED(CLK)
+	struct dwc3_of_simple *simple = dev_get_platdata(dev);
+	int i;
+#endif
+
+#if CONFIG_IS_ENABLED(DM_RESET)
+	for (i = 0; i < simple->num_resets; i++)
+		reset_assert(&simple->resets[i]);
+
+	if (simple->num_resets)
+		reset_release_all(simple->resets, simple->num_resets);
+#endif
+
+#if CONFIG_IS_ENABLED(CLK)
+	for (i = 0; i < simple->num_clocks; i++)
+		clk_disable(&simple->clks[i]);
+
+	if (simple->num_clocks)
+		clk_release_all(simple->clks, simple->num_clocks);
+#endif
+
+	return dm_scan_fdt_dev(dev);
+}
+
+static const struct udevice_id dwc3_of_simple_ids[] = {
+	{ .compatible = "amlogic,meson-gxl-dwc3" },
+	{ }
+};
+
+U_BOOT_DRIVER(dwc3_of_simple) = {
+	.name = "dwc3-of-simple",
+	.id = UCLASS_SIMPLE_BUS,
+	.of_match = dwc3_of_simple_ids,
+	.probe = dwc3_of_simple_probe,
+	.remove = dwc3_of_simple_remove,
+	.platdata_auto_alloc_size = sizeof(struct dwc3_of_simple),
+	.flags = DM_FLAG_ALLOC_PRIV_DMA,
+};
-- 
2.7.4