1 files changed, 78 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/ccu_reset.c b/drivers/clk/sunxi-ng/ccu_reset.c
new file mode 100644
index 000000000..6577aa18c
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_reset.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Maxime Ripard
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/reset-controller.h>
+
+#include "ccu_reset.h"
+
+static int ccu_reset_assert(struct reset_controller_dev *rcdev,
+			    unsigned long id)
+{
+	struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
+	const struct ccu_reset_map *map = &ccu->reset_map[id];
+	unsigned long flags;
+	u32 reg;
+
+	spin_lock_irqsave(ccu->lock, flags);
+
+	reg = readl(ccu->base + map->reg);
+	writel(reg & ~map->bit, ccu->base + map->reg);
+
+	spin_unlock_irqrestore(ccu->lock, flags);
+
+	return 0;
+}
+
+static int ccu_reset_deassert(struct reset_controller_dev *rcdev,
+			      unsigned long id)
+{
+	struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
+	const struct ccu_reset_map *map = &ccu->reset_map[id];
+	unsigned long flags;
+	u32 reg;
+
+	spin_lock_irqsave(ccu->lock, flags);
+
+	reg = readl(ccu->base + map->reg);
+	writel(reg | map->bit, ccu->base + map->reg);
+
+	spin_unlock_irqrestore(ccu->lock, flags);
+
+	return 0;
+}
+
+static int ccu_reset_reset(struct reset_controller_dev *rcdev,
+			   unsigned long id)
+{
+	ccu_reset_assert(rcdev, id);
+	udelay(10);
+	ccu_reset_deassert(rcdev, id);
+
+	return 0;
+}
+
+static int ccu_reset_status(struct reset_controller_dev *rcdev,
+			    unsigned long id)
+{
+	struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
+	const struct ccu_reset_map *map = &ccu->reset_map[id];
+
+	/*
+	 * The reset control API expects 0 if reset is not asserted,
+	 * which is the opposite of what our hardware uses.
+	 */
+	return !(map->bit & readl(ccu->base + map->reg));
+}
+
+const struct reset_control_ops ccu_reset_ops = {
+	.assert		= ccu_reset_assert,
+	.deassert	= ccu_reset_deassert,
+	.reset		= ccu_reset_reset,
+	.status		= ccu_reset_status,
+};
+EXPORT_SYMBOL_NS_GPL(ccu_reset_ops, SUNXI_CCU);