/* * 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/io.h> #include <linux/amba/bus.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, struct kobj_uevent_env *env) { struct amba_device *pcdev = to_amba_device(dev); int retval = 0; retval = add_uevent_var(env, "AMBA_ID=%08x", pcdev->periphid); return retval; } #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; } #define amba_attr_func(name,fmt,arg...) \ static ssize_t name##_show(struct device *_dev, \ struct device_attribute *attr, char *buf) \ { \ struct amba_device *dev = to_amba_device(_dev); \ return sprintf(buf, fmt, arg); \ } #define amba_attr(name,fmt,arg...) \ amba_attr_func(name,fmt,arg) \ static DEVICE_ATTR(name, S_IRUGO, name##_show, NULL) amba_attr_func(id, "%08x\n", dev->periphid); amba_attr(irq0, "%u\n", dev->irq[0]); amba_attr(irq1, "%u\n", dev->irq[1]); amba_attr_func(resource, "\t%016llx\t%016llx\t%016lx\n", (unsigned long long)dev->res.start, (unsigned long long)dev->res.end, dev->res.flags); static struct device_attribute amba_dev_attrs[] = { __ATTR_RO(id), __ATTR_RO(resource), __ATTR_NULL, }; /* * Primecells are part of the Advanced Microcontroller Bus Architecture, * so we call the bus "amba". */ static struct bus_type amba_bustype = { .name = "amba", .dev_attrs = amba_dev_attrs, .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); static int amba_get_enable_pclk(struct amba_device *pcdev) { struct clk *pclk = clk_get(&pcdev->dev, "apb_pclk"); int ret; pcdev->pclk = pclk; if (IS_ERR(pclk)) return PTR_ERR(pclk); ret = clk_enable(pclk); if (ret) clk_put(pclk); return ret; } static void amba_put_disable_pclk(struct amba_device *pcdev) { struct clk *pclk = pcdev->pclk; clk_disable(pclk); clk_put(pclk); } /* * 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 = amba_lookup(pcdrv->id_table, pcdev); int ret; do { ret = amba_get_enable_pclk(pcdev); if (ret) break; ret = pcdrv->probe(pcdev, id); if (ret == 0) break; amba_put_disable_pclk(pcdev); } while (0); return ret; } static int amba_remove(struct device *dev) { struct amba_device *pcdev = to_amba_device(dev); struct amba_driver *drv = to_amba_driver(dev->driver); int ret = drv->remove(pcdev); amba_put_disable_pclk(pcdev); return ret; } 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); } /** * 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 size; void __iomem *tmp; int i, ret; device_initialize(&dev->dev); /* * Copy from device_add */ if (dev->dev.init_name) { dev_set_name(&dev->dev, "%s", dev->dev.init_name); dev->dev.init_name = NULL; } dev->dev.release = amba_device_release; dev->dev.bus = &amba_bustype; dev->dev.dma_mask = &dev->dma_mask; dev->res.name = dev_name(&dev->dev); 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) goto err_out; /* * Dynamically calculate the size of the resource * and use this for iomap */ size = resource_size(&dev->res); tmp = ioremap(dev->res.start, size); if (!tmp) { ret = -ENOMEM; goto err_release; } ret = amba_get_enable_pclk(dev); if (ret == 0) { u32 pid, cid; /* * Read pid and cid based on size of resource * they are located at end of region */ for (pid = 0, i = 0; i < 4; i++) pid |= (readl(tmp + size - 0x20 + 4 * i) & 255) << (i * 8); for (cid = 0, i = 0; i < 4; i++) cid |= (readl(tmp + size - 0x10 + 4 * i) & 255) << (i * 8); amba_put_disable_pclk(dev); if (cid == AMBA_CID) dev->periphid = pid; if (!dev->periphid) ret = -ENODEV; } iounmap(tmp); if (ret) goto err_release; ret = device_add(&dev->dev); if (ret) goto err_release; if (dev->irq[0] != NO_IRQ) ret = device_create_file(&dev->dev, &dev_attr_irq0); if (ret == 0 && dev->irq[1] != NO_IRQ) ret = device_create_file(&dev->dev, &dev_attr_irq1); if (ret == 0) return ret; device_unregister(&dev->dev); err_release: release_resource(&dev->res); err_out: 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_name(dev), 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; u32 size; if (!name) name = dev->dev.driver->name; size = resource_size(&dev->res); if (!request_mem_region(dev->res.start, size, 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) { u32 size; size = resource_size(&dev->res); release_mem_region(dev->res.start, size); } 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);