[U-Boot] [RFC 20/35] reset: sunxi: Add initial RESET driver for A10/A20

[Jagan Teki]

Add initial reset driver for Allwinner A10/A20.

Implement reset deassert and assert functions for
USB OHCI, EHCI, OTG and PHY bus reset and clock registers.

Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
---
 drivers/reset/sunxi/Kconfig     |  7 +++
 drivers/reset/sunxi/Makefile    |  1 +
 drivers/reset/sunxi/reset_a10.c | 95 +++++++++++++++++++++++++++++++++
 3 files changed, 103 insertions(+)
 create mode 100644 drivers/reset/sunxi/reset_a10.c

diff --git a/drivers/reset/sunxi/Kconfig b/drivers/reset/sunxi/Kconfig
index 5c3b79eb76..523201a4e9 100644
--- a/drivers/reset/sunxi/Kconfig
+++ b/drivers/reset/sunxi/Kconfig
@@ -9,6 +9,13 @@ config RESET_SUNXI
 
 if RESET_SUNXI
 
+config RESET_SUN4I_A10
+	bool "Reset driver for Allwinner A10/A20"
+	default MACH_SUN4I || MACH_SUN7I
+	help
+	  This enables common reset driver support for platforms based
+	  on Allwinner A10/A20 SoC.
+
 config RESET_SUN8I_H3
 	bool "Reset driver for Allwinner H3/H5"
 	default MACH_SUNXI_H3_H5
diff --git a/drivers/reset/sunxi/Makefile b/drivers/reset/sunxi/Makefile
index 6e4273b344..6dc0520b6a 100644
--- a/drivers/reset/sunxi/Makefile
+++ b/drivers/reset/sunxi/Makefile
@@ -4,5 +4,6 @@
 # SPDX-License-Identifier:      GPL-2.0+
 #
 
+obj-$(CONFIG_RESET_SUN4I_A10) += reset_a10.o
 obj-$(CONFIG_RESET_SUN8I_H3) += reset_h3.o
 obj-$(CONFIG_RESET_SUN50I_A64) += reset_a64.o
diff --git a/drivers/reset/sunxi/reset_a10.c b/drivers/reset/sunxi/reset_a10.c
new file mode 100644
index 0000000000..d964ea42e8
--- /dev/null
+++ b/drivers/reset/sunxi/reset_a10.c
@@ -0,0 +1,95 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (C) 2018 Amarula Solutions B.V.
+ * Author: Jagan Teki <jagan at amarulasolutions.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <reset-uclass.h>
+#include <asm/io.h>
+#include <dm/lists.h>
+#include <dt-bindings/reset/sun4i-a10-ccu.h>
+
+struct a10_reset_priv {
+	void *base;
+};
+
+static int a10_reset_request(struct reset_ctl *reset_ctl)
+{
+	debug("%s(#%ld)\n", __func__, reset_ctl->id);
+
+	/* check dt-bindings/reset/sun4i-a10-ccu.h for max id */
+	if (reset_ctl->id > 22)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int a10_reset_free(struct reset_ctl *reset_ctl)
+{
+	debug("%s(#%ld)\n", __func__, reset_ctl->id);
+
+	return 0;
+}
+
+static int a10_reset_assert(struct reset_ctl *reset_ctl)
+{
+	struct a10_reset_priv *priv = dev_get_priv(reset_ctl->dev);
+
+	debug("%s(#%ld)\n", __func__, reset_ctl->id);
+
+	switch (reset_ctl->id) {
+	case RST_USB_PHY0:
+	case RST_USB_PHY1:
+	case RST_USB_PHY2:
+		clrbits_le32(priv->base + 0x0cc, BIT(reset_ctl->id));
+		return 0;
+	default:
+		debug("%s (RST#%ld) unhandled\n", __func__, reset_ctl->id);
+		return -ENODEV;
+	}
+}
+
+static int a10_reset_deassert(struct reset_ctl *reset_ctl)
+{
+	struct a10_reset_priv *priv = dev_get_priv(reset_ctl->dev);
+
+	debug("%s(#%ld)\n", __func__, reset_ctl->id);
+
+	switch (reset_ctl->id) {
+	case RST_USB_PHY0:
+	case RST_USB_PHY1:
+	case RST_USB_PHY2:
+		setbits_le32(priv->base + 0x0cc, BIT(reset_ctl->id));
+		return 0;
+	default:
+		debug("%s (RST#%ld) unhandled\n", __func__, reset_ctl->id);
+		return -ENODEV;
+	}
+}
+
+struct reset_ops a10_reset_ops = {
+	.request = a10_reset_request,
+	.free = a10_reset_free,
+	.rst_assert = a10_reset_assert,
+	.rst_deassert = a10_reset_deassert,
+};
+
+static int a10_reset_probe(struct udevice *dev)
+{
+	struct a10_reset_priv *priv = dev_get_priv(dev);
+
+	priv->base = dev_read_addr_ptr(dev);
+
+	return 0;
+}
+
+U_BOOT_DRIVER(reset_sun4i_a10) = {
+	.name		= "sun4i_a10_reset",
+	.id		= UCLASS_RESET,
+	.ops		= &a10_reset_ops,
+	.probe		= a10_reset_probe,
+	.priv_auto_alloc_size = sizeof(struct a10_reset_priv),
+};
-- 
2.17.1