usb: host: Add simple of glue driver for DWC3 USB Controllers integration
This is a port of the dwc3-of-simple driver from Linux to enable/deassert
clock and resets of a simple DWC3 Controller HW glue.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/drivers/usb/host/dwc3-of-simple.c b/drivers/usb/host/dwc3-of-simple.c
new file mode 100644
index 0000000..54a5f60
--- /dev/null
+++ b/drivers/usb/host/dwc3-of-simple.c
@@ -0,0 +1,109 @@
+/*
+ * 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 {
+ struct clk_bulk clks;
+ struct reset_ctl_bulk resets;
+};
+
+static int dwc3_of_simple_reset_init(struct udevice *dev,
+ struct dwc3_of_simple *simple)
+{
+ int ret;
+
+ ret = reset_get_bulk(dev, &simple->resets);
+ if (ret == -ENOTSUPP)
+ return 0;
+ else if (ret)
+ return ret;
+
+ ret = reset_deassert_bulk(&simple->resets);
+ if (ret) {
+ reset_release_bulk(&simple->resets);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int dwc3_of_simple_clk_init(struct udevice *dev,
+ struct dwc3_of_simple *simple)
+{
+ int ret;
+
+ ret = clk_get_bulk(dev, &simple->clks);
+ if (ret == -ENOTSUPP)
+ return 0;
+ if (ret)
+ return ret;
+
+#if CONFIG_IS_ENABLED(CLK)
+ ret = clk_enable_bulk(&simple->clks);
+ if (ret) {
+ clk_release_bulk(&simple->clks);
+ return ret;
+ }
+#endif
+
+ return 0;
+}
+
+static int dwc3_of_simple_probe(struct udevice *dev)
+{
+ struct dwc3_of_simple *simple = dev_get_platdata(dev);
+ int ret;
+
+ ret = dwc3_of_simple_clk_init(dev, simple);
+ if (ret)
+ return ret;
+
+ ret = dwc3_of_simple_reset_init(dev, simple);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int dwc3_of_simple_remove(struct udevice *dev)
+{
+ struct dwc3_of_simple *simple = dev_get_platdata(dev);
+
+ reset_release_bulk(&simple->resets);
+
+ clk_release_bulk(&simple->clks);
+
+ 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,
+};