Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 210 insertions, 0 deletions

diff --git a/drivers/reset/reset-lantiq.c b/drivers/reset/reset-lantiq.c
new file mode 100644
index 000000000..b936cfe85
--- /dev/null
+++ b/drivers/reset/reset-lantiq.c
@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ *  Copyright (C) 2010 John Crispin <blogic@phrozen.org>
+ *  Copyright (C) 2013-2015 Lantiq Beteiligungs-GmbH & Co.KG
+ *  Copyright (C) 2016 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
+ *  Copyright (C) 2017 Hauke Mehrtens <hauke@hauke-m.de>
+ */
+
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+
+#define LANTIQ_RCU_RESET_TIMEOUT	10000
+
+struct lantiq_rcu_reset_priv {
+	struct reset_controller_dev rcdev;
+	struct device *dev;
+	struct regmap *regmap;
+	u32 reset_offset;
+	u32 status_offset;
+};
+
+static struct lantiq_rcu_reset_priv *to_lantiq_rcu_reset_priv(
+	struct reset_controller_dev *rcdev)
+{
+	return container_of(rcdev, struct lantiq_rcu_reset_priv, rcdev);
+}
+
+static int lantiq_rcu_reset_status(struct reset_controller_dev *rcdev,
+				   unsigned long id)
+{
+	struct lantiq_rcu_reset_priv *priv = to_lantiq_rcu_reset_priv(rcdev);
+	unsigned int status = (id >> 8) & 0x1f;
+	u32 val;
+	int ret;
+
+	ret = regmap_read(priv->regmap, priv->status_offset, &val);
+	if (ret)
+		return ret;
+
+	return !!(val & BIT(status));
+}
+
+static int lantiq_rcu_reset_status_timeout(struct reset_controller_dev *rcdev,
+					   unsigned long id, bool assert)
+{
+	int ret;
+	int retry = LANTIQ_RCU_RESET_TIMEOUT;
+
+	do {
+		ret = lantiq_rcu_reset_status(rcdev, id);
+		if (ret < 0)
+			return ret;
+		if (ret == assert)
+			return 0;
+		usleep_range(20, 40);
+	} while (--retry);
+
+	return -ETIMEDOUT;
+}
+
+static int lantiq_rcu_reset_update(struct reset_controller_dev *rcdev,
+				   unsigned long id, bool assert)
+{
+	struct lantiq_rcu_reset_priv *priv = to_lantiq_rcu_reset_priv(rcdev);
+	unsigned int set = id & 0x1f;
+	u32 val = assert ? BIT(set) : 0;
+	int ret;
+
+	ret = regmap_update_bits(priv->regmap, priv->reset_offset, BIT(set),
+				 val);
+	if (ret) {
+		dev_err(priv->dev, "Failed to set reset bit %u\n", set);
+		return ret;
+	}
+
+
+	ret = lantiq_rcu_reset_status_timeout(rcdev, id, assert);
+	if (ret)
+		dev_err(priv->dev, "Failed to %s bit %u\n",
+			assert ? "assert" : "deassert", set);
+
+	return ret;
+}
+
+static int lantiq_rcu_reset_assert(struct reset_controller_dev *rcdev,
+			     unsigned long id)
+{
+	return lantiq_rcu_reset_update(rcdev, id, true);
+}
+
+static int lantiq_rcu_reset_deassert(struct reset_controller_dev *rcdev,
+			       unsigned long id)
+{
+	return lantiq_rcu_reset_update(rcdev, id, false);
+}
+
+static int lantiq_rcu_reset_reset(struct reset_controller_dev *rcdev,
+			    unsigned long id)
+{
+	int ret;
+
+	ret = lantiq_rcu_reset_assert(rcdev, id);
+	if (ret)
+		return ret;
+
+	return lantiq_rcu_reset_deassert(rcdev, id);
+}
+
+static const struct reset_control_ops lantiq_rcu_reset_ops = {
+	.assert = lantiq_rcu_reset_assert,
+	.deassert = lantiq_rcu_reset_deassert,
+	.status = lantiq_rcu_reset_status,
+	.reset	= lantiq_rcu_reset_reset,
+};
+
+static int lantiq_rcu_reset_of_parse(struct platform_device *pdev,
+			       struct lantiq_rcu_reset_priv *priv)
+{
+	struct device *dev = &pdev->dev;
+	const __be32 *offset;
+
+	priv->regmap = syscon_node_to_regmap(dev->of_node->parent);
+	if (IS_ERR(priv->regmap)) {
+		dev_err(&pdev->dev, "Failed to lookup RCU regmap\n");
+		return PTR_ERR(priv->regmap);
+	}
+
+	offset = of_get_address(dev->of_node, 0, NULL, NULL);
+	if (!offset) {
+		dev_err(&pdev->dev, "Failed to get RCU reset offset\n");
+		return -ENOENT;
+	}
+	priv->reset_offset = __be32_to_cpu(*offset);
+
+	offset = of_get_address(dev->of_node, 1, NULL, NULL);
+	if (!offset) {
+		dev_err(&pdev->dev, "Failed to get RCU status offset\n");
+		return -ENOENT;
+	}
+	priv->status_offset = __be32_to_cpu(*offset);
+
+	return 0;
+}
+
+static int lantiq_rcu_reset_xlate(struct reset_controller_dev *rcdev,
+				  const struct of_phandle_args *reset_spec)
+{
+	unsigned int status, set;
+
+	set = reset_spec->args[0];
+	status = reset_spec->args[1];
+
+	if (set >= rcdev->nr_resets || status >= rcdev->nr_resets)
+		return -EINVAL;
+
+	return (status << 8) | set;
+}
+
+static int lantiq_rcu_reset_probe(struct platform_device *pdev)
+{
+	struct lantiq_rcu_reset_priv *priv;
+	int err;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = &pdev->dev;
+	platform_set_drvdata(pdev, priv);
+
+	err = lantiq_rcu_reset_of_parse(pdev, priv);
+	if (err)
+		return err;
+
+	priv->rcdev.ops = &lantiq_rcu_reset_ops;
+	priv->rcdev.owner = THIS_MODULE;
+	priv->rcdev.of_node = pdev->dev.of_node;
+	priv->rcdev.nr_resets = 32;
+	priv->rcdev.of_xlate = lantiq_rcu_reset_xlate;
+	priv->rcdev.of_reset_n_cells = 2;
+
+	return devm_reset_controller_register(&pdev->dev, &priv->rcdev);
+}
+
+static const struct of_device_id lantiq_rcu_reset_dt_ids[] = {
+	{ .compatible = "lantiq,danube-reset", },
+	{ .compatible = "lantiq,xrx200-reset", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, lantiq_rcu_reset_dt_ids);
+
+static struct platform_driver lantiq_rcu_reset_driver = {
+	.probe	= lantiq_rcu_reset_probe,
+	.driver = {
+		.name		= "lantiq-reset",
+		.of_match_table	= lantiq_rcu_reset_dt_ids,
+	},
+};
+module_platform_driver(lantiq_rcu_reset_driver);
+
+MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
+MODULE_DESCRIPTION("Lantiq XWAY RCU Reset Controller Driver");
+MODULE_LICENSE("GPL");