/* * platform.c - platform 'pseudo' bus for legacy devices * * Copyright (c) 2002-3 Patrick Mochel * Copyright (c) 2002-3 Open Source Development Labs * * This file is released under the GPLv2 * * Please see Documentation/driver-model/platform.txt for more * information. */ #include <linux/platform_device.h> #include <linux/module.h> #include <linux/init.h> #include <linux/dma-mapping.h> #include <linux/bootmem.h> #include <linux/err.h> #include <linux/slab.h> #include "base.h" #define to_platform_driver(drv) (container_of((drv), struct platform_driver, driver)) struct device platform_bus = { .bus_id = "platform", }; EXPORT_SYMBOL_GPL(platform_bus); /** * platform_get_resource - get a resource for a device * @dev: platform device * @type: resource type * @num: resource index */ struct resource * platform_get_resource(struct platform_device *dev, unsigned int type, unsigned int num) { int i; for (i = 0; i < dev->num_resources; i++) { struct resource *r = &dev->resource[i]; if ((r->flags & (IORESOURCE_IO|IORESOURCE_MEM| IORESOURCE_IRQ|IORESOURCE_DMA)) == type) if (num-- == 0) return r; } return NULL; } EXPORT_SYMBOL_GPL(platform_get_resource); /** * platform_get_irq - get an IRQ for a device * @dev: platform device * @num: IRQ number index */ int platform_get_irq(struct platform_device *dev, unsigned int num) { struct resource *r = platform_get_resource(dev, IORESOURCE_IRQ, num); return r ? r->start : -ENXIO; } EXPORT_SYMBOL_GPL(platform_get_irq); /** * platform_get_resource_byname - get a resource for a device by name * @dev: platform device * @type: resource type * @name: resource name */ struct resource * platform_get_resource_byname(struct platform_device *dev, unsigned int type, char *name) { int i; for (i = 0; i < dev->num_resources; i++) { struct resource *r = &dev->resource[i]; if ((r->flags & (IORESOURCE_IO|IORESOURCE_MEM| IORESOURCE_IRQ|IORESOURCE_DMA)) == type) if (!strcmp(r->name, name)) return r; } return NULL; } EXPORT_SYMBOL_GPL(platform_get_resource_byname); /** * platform_get_irq - get an IRQ for a device * @dev: platform device * @name: IRQ name */ int platform_get_irq_byname(struct platform_device *dev, char *name) { struct resource *r = platform_get_resource_byname(dev, IORESOURCE_IRQ, name); return r ? r->start : -ENXIO; } EXPORT_SYMBOL_GPL(platform_get_irq_byname); /** * platform_add_devices - add a numbers of platform devices * @devs: array of platform devices to add * @num: number of platform devices in array */ int platform_add_devices(struct platform_device **devs, int num) { int i, ret = 0; for (i = 0; i < num; i++) { ret = platform_device_register(devs[i]); if (ret) { while (--i >= 0) platform_device_unregister(devs[i]); break; } } return ret; } EXPORT_SYMBOL_GPL(platform_add_devices); struct platform_object { struct platform_device pdev; char name[1]; }; /** * platform_device_put * @pdev: platform device to free * * Free all memory associated with a platform device. This function * must _only_ be externally called in error cases. All other usage * is a bug. */ void platform_device_put(struct platform_device *pdev) { if (pdev) put_device(&pdev->dev); } EXPORT_SYMBOL_GPL(platform_device_put); static void platform_device_release(struct device *dev) { struct platform_object *pa = container_of(dev, struct platform_object, pdev.dev); kfree(pa->pdev.dev.platform_data); kfree(pa->pdev.resource); kfree(pa); } /** * platform_device_alloc * @name: base name of the device we're adding * @id: instance id * * Create a platform device object which can have other objects attached * to it, and which will have attached objects freed when it is released. * * This device will be marked as not supporting hotpluggable drivers; no * device add/remove uevents will be generated. In the unusual case that * the device isn't being dynamically allocated as a legacy "probe the * hardware" driver, infrastructure code should reverse this marking. */ struct platform_device *platform_device_alloc(const char *name, unsigned int id) { struct platform_object *pa; pa = kzalloc(sizeof(struct platform_object) + strlen(name), GFP_KERNEL); if (pa) { strcpy(pa->name, name); pa->pdev.name = pa->name; pa->pdev.id = id; device_initialize(&pa->pdev.dev); pa->pdev.dev.release = platform_device_release; /* prevent hotplug "modprobe $(MODALIAS)" from causing trouble in * legacy probe-the-hardware drivers, which don't properly split * out device enumeration logic from drivers. */ pa->pdev.dev.uevent_suppress = 1; } return pa ? &pa->pdev : NULL; } EXPORT_SYMBOL_GPL(platform_device_alloc); /** * platform_device_add_resources * @pdev: platform device allocated by platform_device_alloc to add resources to * @res: set of resources that needs to be allocated for the device * @num: number of resources * * Add a copy of the resources to the platform device. The memory * associated with the resources will be freed when the platform * device is released. */ int platform_device_add_resources(struct platform_device *pdev, struct resource *res, unsigned int num) { struct resource *r; r = kmalloc(sizeof(struct resource) * num, GFP_KERNEL); if (r) { memcpy(r, res, sizeof(struct resource) * num); pdev->resource = r; pdev->num_resources = num; } return r ? 0 : -ENOMEM; } EXPORT_SYMBOL_GPL(platform_device_add_resources); /** * platform_device_add_data * @pdev: platform device allocated by platform_device_alloc to add resources to * @data: platform specific data for this platform device * @size: size of platform specific data * * Add a copy of platform specific data to the platform device's platform_data * pointer. The memory associated with the platform data will be freed * when the platform device is released. */ int platform_device_add_data(struct platform_device *pdev, const void *data, size_t size) { void *d; d = kmalloc(size, GFP_KERNEL); if (d) { memcpy(d, data, size); pdev->dev.platform_data = d; } return d ? 0 : -ENOMEM; } EXPORT_SYMBOL_GPL(platform_device_add_data); /** * platform_device_add - add a platform device to device hierarchy * @pdev: platform device we're adding * * This is part 2 of platform_device_register(), though may be called * separately _iff_ pdev was allocated by platform_device_alloc(). */ int platform_device_add(struct platform_device *pdev) { int i, ret = 0; if (!pdev) return -EINVAL; if (!pdev->dev.parent) pdev->dev.parent = &platform_bus; pdev->dev.bus = &platform_bus_type; if (pdev->id != -1) snprintf(pdev->dev.bus_id, BUS_ID_SIZE, "%s.%u", pdev->name, pdev->id); else strlcpy(pdev->dev.bus_id, pdev->name, BUS_ID_SIZE); for (i = 0; i < pdev->num_resources; i++) { struct resource *p, *r = &pdev->resource[i]; if (r->name == NULL) r->name = pdev->dev.bus_id; p = r->parent; if (!p) { if (r->flags & IORESOURCE_MEM) p = &iomem_resource; else if (r->flags & IORESOURCE_IO) p = &ioport_resource; } if (p && insert_resource(p, r)) { printk(KERN_ERR "%s: failed to claim resource %d\n", pdev->dev.bus_id, i); ret = -EBUSY; goto failed; } } pr_debug("Registering platform device '%s'. Parent at %s\n", pdev->dev.bus_id, pdev->dev.parent->bus_id); ret = device_add(&pdev->dev); if (ret == 0) return ret; failed: while (--i >= 0) if (pdev->resource[i].flags & (IORESOURCE_MEM|IORESOURCE_IO)) release_resource(&pdev->resource[i]); return ret; } EXPORT_SYMBOL_GPL(platform_device_add); /** * platform_device_del - remove a platform-level device * @pdev: platform device we're removing * * Note that this function will also release all memory- and port-based * resources owned by the device (@dev->resource). This function * must _only_ be externally called in error cases. All other usage * is a bug. */ void platform_device_del(struct platform_device *pdev) { int i; if (pdev) { device_del(&pdev->dev); for (i = 0; i < pdev->num_resources; i++) { struct resource *r = &pdev->resource[i]; if (r->flags & (IORESOURCE_MEM|IORESOURCE_IO)) release_resource(r); } } } EXPORT_SYMBOL_GPL(platform_device_del); /** * platform_device_register - add a platform-level device * @pdev: platform device we're adding * */ int platform_device_register(struct platform_device * pdev) { device_initialize(&pdev->dev); return platform_device_add(pdev); } EXPORT_SYMBOL_GPL(platform_device_register); /** * platform_device_unregister - unregister a platform-level device * @pdev: platform device we're unregistering * * Unregistration is done in 2 steps. First we release all resources * and remove it from the subsystem, then we drop reference count by * calling platform_device_put(). */ void platform_device_unregister(struct platform_device * pdev) { platform_device_del(pdev); platform_device_put(pdev); } EXPORT_SYMBOL_GPL(platform_device_unregister); /** * platform_device_register_simple * @name: base name of the device we're adding * @id: instance id * @res: set of resources that needs to be allocated for the device * @num: number of resources * * This function creates a simple platform device that requires minimal * resource and memory management. Canned release function freeing * memory allocated for the device allows drivers using such devices * to be unloaded without waiting for the last reference to the device * to be dropped. * * This interface is primarily intended for use with legacy drivers * which probe hardware directly. Because such drivers create sysfs * device nodes themselves, rather than letting system infrastructure * handle such device enumeration tasks, they don't fully conform to * the Linux driver model. In particular, when such drivers are built * as modules, they can't be "hotplugged". */ struct platform_device *platform_device_register_simple(char *name, unsigned int id, struct resource *res, unsigned int num) { struct platform_device *pdev; int retval; pdev = platform_device_alloc(name, id); if (!pdev) { retval = -ENOMEM; goto error; } if (num) { retval = platform_device_add_resources(pdev, res, num); if (retval) goto error; } retval = platform_device_add(pdev); if (retval) goto error; return pdev; error: platform_device_put(pdev); return ERR_PTR(retval); } EXPORT_SYMBOL_GPL(platform_device_register_simple); static int platform_drv_probe(struct device *_dev) { struct platform_driver *drv = to_platform_driver(_dev->driver); struct platform_device *dev = to_platform_device(_dev); return drv->probe(dev); } static int platform_drv_probe_fail(struct device *_dev) { return -ENXIO; } static int platform_drv_remove(struct device *_dev) { struct platform_driver *drv = to_platform_driver(_dev->driver); struct platform_device *dev = to_platform_device(_dev); return drv->remove(dev); } static void platform_drv_shutdown(struct device *_dev) { struct platform_driver *drv = to_platform_driver(_dev->driver); struct platform_device *dev = to_platform_device(_dev); drv->shutdown(dev); } static int platform_drv_suspend(struct device *_dev, pm_message_t state) { struct platform_driver *drv = to_platform_driver(_dev->driver); struct platform_device *dev = to_platform_device(_dev); return drv->suspend(dev, state); } static int platform_drv_resume(struct device *_dev) { struct platform_driver *drv = to_platform_driver(_dev->driver); struct platform_device *dev = to_platform_device(_dev); return drv->resume(dev); } /** * platform_driver_register * @drv: platform driver structure */ int platform_driver_register(struct platform_driver *drv) { drv->driver.bus = &platform_bus_type; if (drv->probe) drv->driver.probe = platform_drv_probe; if (drv->remove) drv->driver.remove = platform_drv_remove; if (drv->shutdown) drv->driver.shutdown = platform_drv_shutdown; if (drv->suspend) drv->driver.suspend = platform_drv_suspend; if (drv->resume) drv->driver.resume = platform_drv_resume; return driver_register(&drv->driver); } EXPORT_SYMBOL_GPL(platform_driver_register); /** * platform_driver_unregister * @drv: platform driver structure */ void platform_driver_unregister(struct platform_driver *drv) { driver_unregister(&drv->driver); } EXPORT_SYMBOL_GPL(platform_driver_unregister); /** * platform_driver_probe - register driver for non-hotpluggable device * @drv: platform driver structure * @probe: the driver probe routine, probably from an __init section * * Use this instead of platform_driver_register() when you know the device * is not hotpluggable and has already been registered, and you want to * remove its run-once probe() infrastructure from memory after the driver * has bound to the device. * * One typical use for this would be with drivers for controllers integrated * into system-on-chip processors, where the controller devices have been * configured as part of board setup. * * Returns zero if the driver registered and bound to a device, else returns * a negative error code and with the driver not registered. */ int __init_or_module platform_driver_probe(struct platform_driver *drv, int (*probe)(struct platform_device *)) { int retval, code; /* temporary section violation during probe() */ drv->probe = probe; retval = code = platform_driver_register(drv); /* Fixup that section violation, being paranoid about code scanning * the list of drivers in order to probe new devices. Check to see * if the probe was successful, and make sure any forced probes of * new devices fail. */ spin_lock(&platform_bus_type.klist_drivers.k_lock); drv->probe = NULL; if (code == 0 && list_empty(&drv->driver.klist_devices.k_list)) retval = -ENODEV; drv->driver.probe = platform_drv_probe_fail; spin_unlock(&platform_bus_type.klist_drivers.k_lock); if (code != retval) platform_driver_unregister(drv); return retval; } EXPORT_SYMBOL_GPL(platform_driver_probe); /* modalias support enables more hands-off userspace setup: * (a) environment variable lets new-style hotplug events work once system is * fully running: "modprobe $MODALIAS" * (b) sysfs attribute lets new-style coldplug recover from hotplug events * mishandled before system is fully running: "modprobe $(cat modalias)" */ static ssize_t modalias_show(struct device *dev, struct device_attribute *a, char *buf) { struct platform_device *pdev = to_platform_device(dev); int len = snprintf(buf, PAGE_SIZE, "%s\n", pdev->name); return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; } static struct device_attribute platform_dev_attrs[] = { __ATTR_RO(modalias), __ATTR_NULL, }; static int platform_uevent(struct device *dev, char **envp, int num_envp, char *buffer, int buffer_size) { struct platform_device *pdev = to_platform_device(dev); envp[0] = buffer; snprintf(buffer, buffer_size, "MODALIAS=%s", pdev->name); return 0; } /** * platform_match - bind platform device to platform driver. * @dev: device. * @drv: driver. * * Platform device IDs are assumed to be encoded like this: * "<name><instance>", where <name> is a short description of the * type of device, like "pci" or "floppy", and <instance> is the * enumerated instance of the device, like '0' or '42'. * Driver IDs are simply "<name>". * So, extract the <name> from the platform_device structure, * and compare it against the name of the driver. Return whether * they match or not. */ static int platform_match(struct device * dev, struct device_driver * drv) { struct platform_device *pdev = container_of(dev, struct platform_device, dev); return (strncmp(pdev->name, drv->name, BUS_ID_SIZE) == 0); } static int platform_suspend(struct device *dev, pm_message_t mesg) { int ret = 0; if (dev->driver && dev->driver->suspend) ret = dev->driver->suspend(dev, mesg); return ret; } static int platform_suspend_late(struct device *dev, pm_message_t mesg) { struct platform_driver *drv = to_platform_driver(dev->driver); struct platform_device *pdev = container_of(dev, struct platform_device, dev); int ret = 0; if (dev->driver && drv->suspend_late) ret = drv->suspend_late(pdev, mesg); return ret; } static int platform_resume_early(struct device *dev) { struct platform_driver *drv = to_platform_driver(dev->driver); struct platform_device *pdev = container_of(dev, struct platform_device, dev); int ret = 0; if (dev->driver && drv->resume_early) ret = drv->resume_early(pdev); return ret; } static int platform_resume(struct device * dev) { int ret = 0; if (dev->driver && dev->driver->resume) ret = dev->driver->resume(dev); return ret; } struct bus_type platform_bus_type = { .name = "platform", .dev_attrs = platform_dev_attrs, .match = platform_match, .uevent = platform_uevent, .suspend = platform_suspend, .suspend_late = platform_suspend_late, .resume_early = platform_resume_early, .resume = platform_resume, }; EXPORT_SYMBOL_GPL(platform_bus_type); int __init platform_bus_init(void) { int error; error = device_register(&platform_bus); if (error) return error; error = bus_register(&platform_bus_type); if (error) device_unregister(&platform_bus); return error; } #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK u64 dma_get_required_mask(struct device *dev) { u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT); u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT)); u64 mask; if (!high_totalram) { /* convert to mask just covering totalram */ low_totalram = (1 << (fls(low_totalram) - 1)); low_totalram += low_totalram - 1; mask = low_totalram; } else { high_totalram = (1 << (fls(high_totalram) - 1)); high_totalram += high_totalram - 1; mask = (((u64)high_totalram) << 32) + 0xffffffff; } return mask & *dev->dma_mask; } EXPORT_SYMBOL_GPL(dma_get_required_mask); #endif