[ARM] Move AMBA bus code to drivers/amba/

Make the AMBA bus code visible to other architectures.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

3 files changed, 362 insertions, 0 deletions

diff --git a/drivers/Makefile b/drivers/Makefile
index ea410b6..7fc3f0f 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_ACPI)		+= acpi/
 # PnP must come after ACPI since it will eventually need to check if acpi
 # was used and do nothing if so
 obj-$(CONFIG_PNP)		+= pnp/
+obj-$(CONFIG_ARM_AMBA)		+= amba/
 
 # char/ comes before serial/ etc so that the VT console is the boot-time
 # default.
diff --git a/drivers/amba/Makefile b/drivers/amba/Makefile
new file mode 100644
index 0000000..40fe740
--- /dev/null
+++ b/drivers/amba/Makefile
@@ -0,0 +1,2 @@
+obj-y		+= bus.o
+
diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c
new file mode 100644
index 0000000..1bbdd16
--- /dev/null
+++ b/drivers/amba/bus.c
@@ -0,0 +1,359 @@
+/*
+ *  linux/arch/arm/common/amba.c
+ *
+ *  Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/amba/bus.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/sizes.h>
+
+#define to_amba_device(d)	container_of(d, struct amba_device, dev)
+#define to_amba_driver(d)	container_of(d, struct amba_driver, drv)
+
+static struct amba_id *
+amba_lookup(struct amba_id *table, struct amba_device *dev)
+{
+	int ret = 0;
+
+	while (table->mask) {
+		ret = (dev->periphid & table->mask) == table->id;
+		if (ret)
+			break;
+		table++;
+	}
+
+	return ret ? table : NULL;
+}
+
+static int amba_match(struct device *dev, struct device_driver *drv)
+{
+	struct amba_device *pcdev = to_amba_device(dev);
+	struct amba_driver *pcdrv = to_amba_driver(drv);
+
+	return amba_lookup(pcdrv->id_table, pcdev) != NULL;
+}
+
+#ifdef CONFIG_HOTPLUG
+static int amba_uevent(struct device *dev, char **envp, int nr_env, char *buf, int bufsz)
+{
+	struct amba_device *pcdev = to_amba_device(dev);
+
+	if (nr_env < 2)
+		return -ENOMEM;
+
+	snprintf(buf, bufsz, "AMBA_ID=%08x", pcdev->periphid);
+	*envp++ = buf;
+	*envp++ = NULL;
+	return 0;
+}
+#else
+#define amba_uevent NULL
+#endif
+
+static int amba_suspend(struct device *dev, pm_message_t state)
+{
+	struct amba_driver *drv = to_amba_driver(dev->driver);
+	int ret = 0;
+
+	if (dev->driver && drv->suspend)
+		ret = drv->suspend(to_amba_device(dev), state);
+	return ret;
+}
+
+static int amba_resume(struct device *dev)
+{
+	struct amba_driver *drv = to_amba_driver(dev->driver);
+	int ret = 0;
+
+	if (dev->driver && drv->resume)
+		ret = drv->resume(to_amba_device(dev));
+	return ret;
+}
+
+/*
+ * Primecells are part of the Advanced Microcontroller Bus Architecture,
+ * so we call the bus "amba".
+ */
+static struct bus_type amba_bustype = {
+	.name		= "amba",
+	.match		= amba_match,
+	.uevent		= amba_uevent,
+	.suspend	= amba_suspend,
+	.resume		= amba_resume,
+};
+
+static int __init amba_init(void)
+{
+	return bus_register(&amba_bustype);
+}
+
+postcore_initcall(amba_init);
+
+/*
+ * These are the device model conversion veneers; they convert the
+ * device model structures to our more specific structures.
+ */
+static int amba_probe(struct device *dev)
+{
+	struct amba_device *pcdev = to_amba_device(dev);
+	struct amba_driver *pcdrv = to_amba_driver(dev->driver);
+	struct amba_id *id;
+
+	id = amba_lookup(pcdrv->id_table, pcdev);
+
+	return pcdrv->probe(pcdev, id);
+}
+
+static int amba_remove(struct device *dev)
+{
+	struct amba_driver *drv = to_amba_driver(dev->driver);
+	return drv->remove(to_amba_device(dev));
+}
+
+static void amba_shutdown(struct device *dev)
+{
+	struct amba_driver *drv = to_amba_driver(dev->driver);
+	drv->shutdown(to_amba_device(dev));
+}
+
+/**
+ *	amba_driver_register - register an AMBA device driver
+ *	@drv: amba device driver structure
+ *
+ *	Register an AMBA device driver with the Linux device model
+ *	core.  If devices pre-exist, the drivers probe function will
+ *	be called.
+ */
+int amba_driver_register(struct amba_driver *drv)
+{
+	drv->drv.bus = &amba_bustype;
+
+#define SETFN(fn)	if (drv->fn) drv->drv.fn = amba_##fn
+	SETFN(probe);
+	SETFN(remove);
+	SETFN(shutdown);
+
+	return driver_register(&drv->drv);
+}
+
+/**
+ *	amba_driver_unregister - remove an AMBA device driver
+ *	@drv: AMBA device driver structure to remove
+ *
+ *	Unregister an AMBA device driver from the Linux device
+ *	model.  The device model will call the drivers remove function
+ *	for each device the device driver is currently handling.
+ */
+void amba_driver_unregister(struct amba_driver *drv)
+{
+	driver_unregister(&drv->drv);
+}
+
+
+static void amba_device_release(struct device *dev)
+{
+	struct amba_device *d = to_amba_device(dev);
+
+	if (d->res.parent)
+		release_resource(&d->res);
+	kfree(d);
+}
+
+#define amba_attr(name,fmt,arg...)				\
+static ssize_t show_##name(struct device *_dev, struct device_attribute *attr, char *buf)	\
+{								\
+	struct amba_device *dev = to_amba_device(_dev);		\
+	return sprintf(buf, fmt, arg);				\
+}								\
+static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
+
+amba_attr(id, "%08x\n", dev->periphid);
+amba_attr(irq0, "%u\n", dev->irq[0]);
+amba_attr(irq1, "%u\n", dev->irq[1]);
+amba_attr(resource, "\t%08lx\t%08lx\t%08lx\n",
+	  dev->res.start, dev->res.end, dev->res.flags);
+
+/**
+ *	amba_device_register - register an AMBA device
+ *	@dev: AMBA device to register
+ *	@parent: parent memory resource
+ *
+ *	Setup the AMBA device, reading the cell ID if present.
+ *	Claim the resource, and register the AMBA device with
+ *	the Linux device manager.
+ */
+int amba_device_register(struct amba_device *dev, struct resource *parent)
+{
+	u32 pid, cid;
+	void __iomem *tmp;
+	int i, ret;
+
+	dev->dev.release = amba_device_release;
+	dev->dev.bus = &amba_bustype;
+	dev->dev.dma_mask = &dev->dma_mask;
+	dev->res.name = dev->dev.bus_id;
+
+	if (!dev->dev.coherent_dma_mask && dev->dma_mask)
+		dev_warn(&dev->dev, "coherent dma mask is unset\n");
+
+	ret = request_resource(parent, &dev->res);
+	if (ret == 0) {
+		tmp = ioremap(dev->res.start, SZ_4K);
+		if (!tmp) {
+			ret = -ENOMEM;
+			goto out;
+		}
+
+		for (pid = 0, i = 0; i < 4; i++)
+			pid |= (readl(tmp + 0xfe0 + 4 * i) & 255) << (i * 8);
+		for (cid = 0, i = 0; i < 4; i++)
+			cid |= (readl(tmp + 0xff0 + 4 * i) & 255) << (i * 8);
+
+		iounmap(tmp);
+
+		if (cid == 0xb105f00d)
+			dev->periphid = pid;
+
+		if (dev->periphid)
+			ret = device_register(&dev->dev);
+		else
+			ret = -ENODEV;
+
+		if (ret == 0) {
+			device_create_file(&dev->dev, &dev_attr_id);
+			if (dev->irq[0] != NO_IRQ)
+				device_create_file(&dev->dev, &dev_attr_irq0);
+			if (dev->irq[1] != NO_IRQ)
+				device_create_file(&dev->dev, &dev_attr_irq1);
+			device_create_file(&dev->dev, &dev_attr_resource);
+		} else {
+ out:
+			release_resource(&dev->res);
+		}
+	}
+	return ret;
+}
+
+/**
+ *	amba_device_unregister - unregister an AMBA device
+ *	@dev: AMBA device to remove
+ *
+ *	Remove the specified AMBA device from the Linux device
+ *	manager.  All files associated with this object will be
+ *	destroyed, and device drivers notified that the device has
+ *	been removed.  The AMBA device's resources including
+ *	the amba_device structure will be freed once all
+ *	references to it have been dropped.
+ */
+void amba_device_unregister(struct amba_device *dev)
+{
+	device_unregister(&dev->dev);
+}
+
+
+struct find_data {
+	struct amba_device *dev;
+	struct device *parent;
+	const char *busid;
+	unsigned int id;
+	unsigned int mask;
+};
+
+static int amba_find_match(struct device *dev, void *data)
+{
+	struct find_data *d = data;
+	struct amba_device *pcdev = to_amba_device(dev);
+	int r;
+
+	r = (pcdev->periphid & d->mask) == d->id;
+	if (d->parent)
+		r &= d->parent == dev->parent;
+	if (d->busid)
+		r &= strcmp(dev->bus_id, d->busid) == 0;
+
+	if (r) {
+		get_device(dev);
+		d->dev = pcdev;
+	}
+
+	return r;
+}
+
+/**
+ *	amba_find_device - locate an AMBA device given a bus id
+ *	@busid: bus id for device (or NULL)
+ *	@parent: parent device (or NULL)
+ *	@id: peripheral ID (or 0)
+ *	@mask: peripheral ID mask (or 0)
+ *
+ *	Return the AMBA device corresponding to the supplied parameters.
+ *	If no device matches, returns NULL.
+ *
+ *	NOTE: When a valid device is found, its refcount is
+ *	incremented, and must be decremented before the returned
+ *	reference.
+ */
+struct amba_device *
+amba_find_device(const char *busid, struct device *parent, unsigned int id,
+		 unsigned int mask)
+{
+	struct find_data data;
+
+	data.dev = NULL;
+	data.parent = parent;
+	data.busid = busid;
+	data.id = id;
+	data.mask = mask;
+
+	bus_for_each_dev(&amba_bustype, NULL, &data, amba_find_match);
+
+	return data.dev;
+}
+
+/**
+ *	amba_request_regions - request all mem regions associated with device
+ *	@dev: amba_device structure for device
+ *	@name: name, or NULL to use driver name
+ */
+int amba_request_regions(struct amba_device *dev, const char *name)
+{
+	int ret = 0;
+
+	if (!name)
+		name = dev->dev.driver->name;
+
+	if (!request_mem_region(dev->res.start, SZ_4K, name))
+		ret = -EBUSY;
+
+	return ret;
+}
+
+/**
+ *	amba_release_regions - release mem regions assoicated with device
+ *	@dev: amba_device structure for device
+ *
+ *	Release regions claimed by a successful call to amba_request_regions.
+ */
+void amba_release_regions(struct amba_device *dev)
+{
+	release_mem_region(dev->res.start, SZ_4K);
+}
+
+EXPORT_SYMBOL(amba_driver_register);
+EXPORT_SYMBOL(amba_driver_unregister);
+EXPORT_SYMBOL(amba_device_register);
+EXPORT_SYMBOL(amba_device_unregister);
+EXPORT_SYMBOL(amba_find_device);
+EXPORT_SYMBOL(amba_request_regions);
+EXPORT_SYMBOL(amba_release_regions);