Merge tag 'reset-for-5.0-rc2' of git://git.pengutronix.de/git/pza/linux into fixes

Late reset controller changes for v5.0

This adds missing deassert functionality to the ARC HSDK reset driver,
fixes some indentation and grammar issues in the kernel docs, adds a
helper to count the number of resets on a device for the non-DT case
as well, adds an early reset driver for SoCFPGA and simple reset driver
support for Stratix10, and generalizes the uniphier USB3 glue layer
reset to also cover AHCI.

* tag 'reset-for-5.0-rc2' of git://git.pengutronix.de/git/pza/linux:
  reset: uniphier-glue: Add AHCI reset control support in glue layer
  dt-bindings: reset: uniphier: Add AHCI core reset description
  reset: uniphier-usb3: Rename to reset-uniphier-glue
  dt-bindings: reset: uniphier: Replace the expression of USB3 with generic peripherals
  ARM: socfpga: dts: document "altr,stratix10-rst-mgr" binding
  reset: socfpga: add an early reset driver for SoCFPGA
  reset: fix null pointer dereference on dev by dev_name
  reset: Add reset_control_get_count()
  reset: Improve reset controller kernel docs
  ARC: HSDK: improve reset driver

Signed-off-by: Olof Johansson <olof@lixom.net>

1 files changed, 183 insertions, 0 deletions

diff --git a/drivers/reset/reset-uniphier-glue.c b/drivers/reset/reset-uniphier-glue.c
new file mode 100644
index 000000000000..a45923f4df6d
--- /dev/null
+++ b/drivers/reset/reset-uniphier-glue.c
@@ -0,0 +1,183 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// reset-uniphier-glue.c - Glue layer reset driver for UniPhier
+// Copyright 2018 Socionext Inc.
+// Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
+
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+#include "reset-simple.h"
+
+#define MAX_CLKS	2
+#define MAX_RSTS	2
+
+struct uniphier_glue_reset_soc_data {
+	int nclks;
+	const char * const *clock_names;
+	int nrsts;
+	const char * const *reset_names;
+};
+
+struct uniphier_glue_reset_priv {
+	struct clk_bulk_data clk[MAX_CLKS];
+	struct reset_control *rst[MAX_RSTS];
+	struct reset_simple_data rdata;
+	const struct uniphier_glue_reset_soc_data *data;
+};
+
+static int uniphier_glue_reset_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct uniphier_glue_reset_priv *priv;
+	struct resource *res;
+	resource_size_t size;
+	const char *name;
+	int i, ret, nr;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->data = of_device_get_match_data(dev);
+	if (WARN_ON(!priv->data || priv->data->nclks > MAX_CLKS ||
+		    priv->data->nrsts > MAX_RSTS))
+		return -EINVAL;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	size = resource_size(res);
+	priv->rdata.membase = devm_ioremap_resource(dev, res);
+	if (IS_ERR(priv->rdata.membase))
+		return PTR_ERR(priv->rdata.membase);
+
+	for (i = 0; i < priv->data->nclks; i++)
+		priv->clk[i].id = priv->data->clock_names[i];
+	ret = devm_clk_bulk_get(dev, priv->data->nclks, priv->clk);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < priv->data->nrsts; i++) {
+		name = priv->data->reset_names[i];
+		priv->rst[i] = devm_reset_control_get_shared(dev, name);
+		if (IS_ERR(priv->rst[i]))
+			return PTR_ERR(priv->rst[i]);
+	}
+
+	ret = clk_bulk_prepare_enable(priv->data->nclks, priv->clk);
+	if (ret)
+		return ret;
+
+	for (nr = 0; nr < priv->data->nrsts; nr++) {
+		ret = reset_control_deassert(priv->rst[nr]);
+		if (ret)
+			goto out_rst_assert;
+	}
+
+	spin_lock_init(&priv->rdata.lock);
+	priv->rdata.rcdev.owner = THIS_MODULE;
+	priv->rdata.rcdev.nr_resets = size * BITS_PER_BYTE;
+	priv->rdata.rcdev.ops = &reset_simple_ops;
+	priv->rdata.rcdev.of_node = dev->of_node;
+	priv->rdata.active_low = true;
+
+	platform_set_drvdata(pdev, priv);
+
+	ret = devm_reset_controller_register(dev, &priv->rdata.rcdev);
+	if (ret)
+		goto out_rst_assert;
+
+	return 0;
+
+out_rst_assert:
+	while (nr--)
+		reset_control_assert(priv->rst[nr]);
+
+	clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
+
+	return ret;
+}
+
+static int uniphier_glue_reset_remove(struct platform_device *pdev)
+{
+	struct uniphier_glue_reset_priv *priv = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < priv->data->nrsts; i++)
+		reset_control_assert(priv->rst[i]);
+
+	clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
+
+	return 0;
+}
+
+static const char * const uniphier_pro4_clock_reset_names[] = {
+	"gio", "link",
+};
+
+static const struct uniphier_glue_reset_soc_data uniphier_pro4_data = {
+	.nclks = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
+	.clock_names = uniphier_pro4_clock_reset_names,
+	.nrsts = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
+	.reset_names = uniphier_pro4_clock_reset_names,
+};
+
+static const char * const uniphier_pxs2_clock_reset_names[] = {
+	"link",
+};
+
+static const struct uniphier_glue_reset_soc_data uniphier_pxs2_data = {
+	.nclks = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
+	.clock_names = uniphier_pxs2_clock_reset_names,
+	.nrsts = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
+	.reset_names = uniphier_pxs2_clock_reset_names,
+};
+
+static const struct of_device_id uniphier_glue_reset_match[] = {
+	{
+		.compatible = "socionext,uniphier-pro4-usb3-reset",
+		.data = &uniphier_pro4_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs2-usb3-reset",
+		.data = &uniphier_pxs2_data,
+	},
+	{
+		.compatible = "socionext,uniphier-ld20-usb3-reset",
+		.data = &uniphier_pxs2_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs3-usb3-reset",
+		.data = &uniphier_pxs2_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pro4-ahci-reset",
+		.data = &uniphier_pro4_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs2-ahci-reset",
+		.data = &uniphier_pxs2_data,
+	},
+	{
+		.compatible = "socionext,uniphier-pxs3-ahci-reset",
+		.data = &uniphier_pxs2_data,
+	},
+	{ /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_glue_reset_match);
+
+static struct platform_driver uniphier_glue_reset_driver = {
+	.probe = uniphier_glue_reset_probe,
+	.remove = uniphier_glue_reset_remove,
+	.driver = {
+		.name = "uniphier-glue-reset",
+		.of_match_table = uniphier_glue_reset_match,
+	},
+};
+module_platform_driver(uniphier_glue_reset_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
+MODULE_DESCRIPTION("UniPhier Glue layer reset driver");
+MODULE_LICENSE("GPL");