+++ /dev/null
-From 8015cea648c452bbfe0fc820dcb1185beaeb8736 Mon Sep 17 00:00:00 2001
-From: Maxime Ripard <maxime.ripard@free-electrons.com>
-Date: Tue, 24 Sep 2013 11:07:43 +0300
-Subject: [PATCH] reset: Add Allwinner SoCs Reset Controller Driver
-
-The Allwinner A31 and most of the other Allwinner SoCs have an IP
-maintaining a few other IPs in the SoC in reset by default. Among these
-IPs are the A31's High Speed Timers, hence why we can't use the regular
-driver construct in every cases, and need to call the registering
-function directly during machine initialisation.
-
-Apart from this, the implementation is fairly straightforward, and could
-easily be moved to a generic MMIO-based reset controller driver if the
-need ever arise.
-
-Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
-Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
----
- drivers/reset/Makefile | 1 +
- drivers/reset/reset-sunxi.c | 175 ++++++++++++++++++++++++++++++++++++++++++++
- 2 files changed, 176 insertions(+)
- create mode 100644 drivers/reset/reset-sunxi.c
-
---- a/drivers/reset/Makefile
-+++ b/drivers/reset/Makefile
-@@ -1 +1,2 @@
- obj-$(CONFIG_RESET_CONTROLLER) += core.o
-+obj-$(CONFIG_ARCH_SUNXI) += reset-sunxi.o
---- /dev/null
-+++ b/drivers/reset/reset-sunxi.c
-@@ -0,0 +1,175 @@
-+/*
-+ * Allwinner SoCs Reset Controller driver
-+ *
-+ * Copyright 2013 Maxime Ripard
-+ *
-+ * Maxime Ripard <maxime.ripard@free-electrons.com>
-+ *
-+ * This program is free software; you can redistribute it and/or modify
-+ * it under the terms of the GNU General Public License as published by
-+ * the Free Software Foundation; either version 2 of the License, or
-+ * (at your option) any later version.
-+ */
-+
-+#include <linux/err.h>
-+#include <linux/io.h>
-+#include <linux/module.h>
-+#include <linux/of.h>
-+#include <linux/of_address.h>
-+#include <linux/platform_device.h>
-+#include <linux/reset-controller.h>
-+#include <linux/slab.h>
-+#include <linux/spinlock.h>
-+#include <linux/types.h>
-+
-+struct sunxi_reset_data {
-+ spinlock_t lock;
-+ void __iomem *membase;
-+ struct reset_controller_dev rcdev;
-+};
-+
-+static int sunxi_reset_assert(struct reset_controller_dev *rcdev,
-+ unsigned long id)
-+{
-+ struct sunxi_reset_data *data = container_of(rcdev,
-+ struct sunxi_reset_data,
-+ rcdev);
-+ int bank = id / BITS_PER_LONG;
-+ int offset = id % BITS_PER_LONG;
-+ unsigned long flags;
-+ u32 reg;
-+
-+ spin_lock_irqsave(&data->lock, flags);
-+
-+ reg = readl(data->membase + (bank * 4));
-+ writel(reg & ~BIT(offset), data->membase + (bank * 4));
-+
-+ spin_unlock_irqrestore(&data->lock, flags);
-+
-+ return 0;
-+}
-+
-+static int sunxi_reset_deassert(struct reset_controller_dev *rcdev,
-+ unsigned long id)
-+{
-+ struct sunxi_reset_data *data = container_of(rcdev,
-+ struct sunxi_reset_data,
-+ rcdev);
-+ int bank = id / BITS_PER_LONG;
-+ int offset = id % BITS_PER_LONG;
-+ unsigned long flags;
-+ u32 reg;
-+
-+ spin_lock_irqsave(&data->lock, flags);
-+
-+ reg = readl(data->membase + (bank * 4));
-+ writel(reg | BIT(offset), data->membase + (bank * 4));
-+
-+ spin_unlock_irqrestore(&data->lock, flags);
-+
-+ return 0;
-+}
-+
-+static struct reset_control_ops sunxi_reset_ops = {
-+ .assert = sunxi_reset_assert,
-+ .deassert = sunxi_reset_deassert,
-+};
-+
-+static int sunxi_reset_init(struct device_node *np)
-+{
-+ struct sunxi_reset_data *data;
-+ struct resource res;
-+ resource_size_t size;
-+ int ret;
-+
-+ data = kzalloc(sizeof(*data), GFP_KERNEL);
-+ if (!data)
-+ return -ENOMEM;
-+
-+ ret = of_address_to_resource(np, 0, &res);
-+ if (ret)
-+ goto err_alloc;
-+
-+ size = resource_size(&res);
-+ if (!request_mem_region(res.start, size, np->name)) {
-+ ret = -EBUSY;
-+ goto err_alloc;
-+ }
-+
-+ data->membase = ioremap(res.start, size);
-+ if (!data->membase) {
-+ ret = -ENOMEM;
-+ goto err_alloc;
-+ }
-+
-+ data->rcdev.owner = THIS_MODULE;
-+ data->rcdev.nr_resets = size * 32;
-+ data->rcdev.ops = &sunxi_reset_ops;
-+ data->rcdev.of_node = np;
-+ reset_controller_register(&data->rcdev);
-+
-+ return 0;
-+
-+err_alloc:
-+ kfree(data);
-+ return ret;
-+};
-+
-+/*
-+ * These are the reset controller we need to initialize early on in
-+ * our system, before we can even think of using a regular device
-+ * driver for it.
-+ */
-+static const struct of_device_id sunxi_early_reset_dt_ids[] __initdata = {
-+ { .compatible = "allwinner,sun6i-a31-ahb1-reset", },
-+ { /* sentinel */ },
-+};
-+
-+void __init sun6i_reset_init(void)
-+{
-+ struct device_node *np;
-+
-+ for_each_matching_node(np, sunxi_early_reset_dt_ids)
-+ sunxi_reset_init(np);
-+}
-+
-+/*
-+ * And these are the controllers we can register through the regular
-+ * device model.
-+ */
-+static const struct of_device_id sunxi_reset_dt_ids[] = {
-+ { .compatible = "allwinner,sun6i-a31-clock-reset", },
-+ { /* sentinel */ },
-+};
-+MODULE_DEVICE_TABLE(of, sunxi_reset_dt_ids);
-+
-+static int sunxi_reset_probe(struct platform_device *pdev)
-+{
-+ return sunxi_reset_init(pdev->dev.of_node);
-+}
-+
-+static int sunxi_reset_remove(struct platform_device *pdev)
-+{
-+ struct sunxi_reset_data *data = platform_get_drvdata(pdev);
-+
-+ reset_controller_unregister(&data->rcdev);
-+ iounmap(data->membase);
-+ kfree(data);
-+
-+ return 0;
-+}
-+
-+static struct platform_driver sunxi_reset_driver = {
-+ .probe = sunxi_reset_probe,
-+ .remove = sunxi_reset_remove,
-+ .driver = {
-+ .name = "sunxi-reset",
-+ .owner = THIS_MODULE,
-+ .of_match_table = sunxi_reset_dt_ids,
-+ },
-+};
-+module_platform_driver(sunxi_reset_driver);
-+
-+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com");
-+MODULE_DESCRIPTION("Allwinner SoCs Reset Controller Driver");
-+MODULE_LICENSE("GPL");
projects / openwrt / svn-archive / archive.git / blobdiff