aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/common/amba.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/common/amba.c')
-rw-r--r--arch/arm/common/amba.c357
1 files changed, 357 insertions, 0 deletions
diff --git a/arch/arm/common/amba.c b/arch/arm/common/amba.c
new file mode 100644
index 000000000000..a0507f8c33fe
--- /dev/null
+++ b/arch/arm/common/amba.c
@@ -0,0 +1,357 @@
+/*
+ * 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 <asm/io.h>
+#include <asm/irq.h>
+#include <asm/hardware/amba.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_hotplug(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_hotplug 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,
+ .hotplug = amba_hotplug,
+ .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, 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);