diff options
Diffstat (limited to 'drivers/base/platform.c')
| -rw-r--r-- | drivers/base/platform.c | 1495 |
1 files changed, 1495 insertions, 0 deletions
diff --git a/drivers/base/platform.c b/drivers/base/platform.c new file mode 100644 index 000000000..349c2754e --- /dev/null +++ b/drivers/base/platform.c @@ -0,0 +1,1495 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * platform.c - platform 'pseudo' bus for legacy devices + * + * Copyright (c) 2002-3 Patrick Mochel + * Copyright (c) 2002-3 Open Source Development Labs + * + * Please see Documentation/driver-model/platform.txt for more + * information. + */ + +#include <linux/string.h> +#include <linux/platform_device.h> +#include <linux/of_device.h> +#include <linux/of_irq.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 <linux/pm_runtime.h> +#include <linux/pm_domain.h> +#include <linux/idr.h> +#include <linux/acpi.h> +#include <linux/clk/clk-conf.h> +#include <linux/limits.h> +#include <linux/property.h> +#include <linux/kmemleak.h> +#include <linux/types.h> + +#include "base.h" +#include "power/power.h" + +/* For automatically allocated device IDs */ +static DEFINE_IDA(platform_devid_ida); + +struct device platform_bus = { + .init_name = "platform", +}; +EXPORT_SYMBOL_GPL(platform_bus); + +/** + * arch_setup_pdev_archdata - Allow manipulation of archdata before its used + * @pdev: platform device + * + * This is called before platform_device_add() such that any pdev_archdata may + * be setup before the platform_notifier is called. So if a user needs to + * manipulate any relevant information in the pdev_archdata they can do: + * + * platform_device_alloc() + * ... manipulate ... + * platform_device_add() + * + * And if they don't care they can just call platform_device_register() and + * everything will just work out. + */ +void __weak arch_setup_pdev_archdata(struct platform_device *pdev) +{ +} + +/** + * 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) +{ + u32 i; + + for (i = 0; i < dev->num_resources; i++) { + struct resource *r = &dev->resource[i]; + + if (type == resource_type(r) && 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) +{ +#ifdef CONFIG_SPARC + /* sparc does not have irqs represented as IORESOURCE_IRQ resources */ + if (!dev || num >= dev->archdata.num_irqs) + return -ENXIO; + return dev->archdata.irqs[num]; +#else + struct resource *r; + if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) { + int ret; + + ret = of_irq_get(dev->dev.of_node, num); + if (ret > 0 || ret == -EPROBE_DEFER) + return ret; + } + + r = platform_get_resource(dev, IORESOURCE_IRQ, num); + if (has_acpi_companion(&dev->dev)) { + if (r && r->flags & IORESOURCE_DISABLED) { + int ret; + + ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r); + if (ret) + return ret; + } + } + + /* + * The resources may pass trigger flags to the irqs that need + * to be set up. It so happens that the trigger flags for + * IORESOURCE_BITS correspond 1-to-1 to the IRQF_TRIGGER* + * settings. + */ + if (r && r->flags & IORESOURCE_BITS) { + struct irq_data *irqd; + + irqd = irq_get_irq_data(r->start); + if (!irqd) + return -ENXIO; + irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS); + } + + return r ? r->start : -ENXIO; +#endif +} +EXPORT_SYMBOL_GPL(platform_get_irq); + +/** + * platform_irq_count - Count the number of IRQs a platform device uses + * @dev: platform device + * + * Return: Number of IRQs a platform device uses or EPROBE_DEFER + */ +int platform_irq_count(struct platform_device *dev) +{ + int ret, nr = 0; + + while ((ret = platform_get_irq(dev, nr)) >= 0) + nr++; + + if (ret == -EPROBE_DEFER) + return ret; + + return nr; +} +EXPORT_SYMBOL_GPL(platform_irq_count); + +/** + * 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, + const char *name) +{ + u32 i; + + for (i = 0; i < dev->num_resources; i++) { + struct resource *r = &dev->resource[i]; + + if (unlikely(!r->name)) + continue; + + if (type == resource_type(r) && !strcmp(r->name, name)) + return r; + } + return NULL; +} +EXPORT_SYMBOL_GPL(platform_get_resource_byname); + +/** + * platform_get_irq_byname - get an IRQ for a device by name + * @dev: platform device + * @name: IRQ name + */ +int platform_get_irq_byname(struct platform_device *dev, const char *name) +{ + struct resource *r; + + if (IS_ENABLED(CONFIG_OF_IRQ) && dev->dev.of_node) { + int ret; + + ret = of_irq_get_byname(dev->dev.of_node, name); + if (ret > 0 || ret == -EPROBE_DEFER) + return ret; + } + + 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[]; +}; + +/** + * platform_device_put - destroy a platform device + * @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); + + of_device_node_put(&pa->pdev.dev); + kfree(pa->pdev.dev.platform_data); + kfree(pa->pdev.mfd_cell); + kfree(pa->pdev.resource); + kfree(pa->pdev.driver_override); + kfree(pa); +} + +/** + * platform_device_alloc - create a platform device + * @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. + */ +struct platform_device *platform_device_alloc(const char *name, int id) +{ + struct platform_object *pa; + + pa = kzalloc(sizeof(*pa) + strlen(name) + 1, 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; + arch_setup_pdev_archdata(&pa->pdev); + } + + return pa ? &pa->pdev : NULL; +} +EXPORT_SYMBOL_GPL(platform_device_alloc); + +/** + * platform_device_add_resources - add resources to a platform device + * @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, + const struct resource *res, unsigned int num) +{ + struct resource *r = NULL; + + if (res) { + r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL); + if (!r) + return -ENOMEM; + } + + kfree(pdev->resource); + pdev->resource = r; + pdev->num_resources = num; + return 0; +} +EXPORT_SYMBOL_GPL(platform_device_add_resources); + +/** + * platform_device_add_data - add platform-specific data to a platform device + * @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 = NULL; + + if (data) { + d = kmemdup(data, size, GFP_KERNEL); + if (!d) + return -ENOMEM; + } + + kfree(pdev->dev.platform_data); + pdev->dev.platform_data = d; + return 0; +} +EXPORT_SYMBOL_GPL(platform_device_add_data); + +/** + * platform_device_add_properties - add built-in properties to a platform device + * @pdev: platform device to add properties to + * @properties: null terminated array of properties to add + * + * The function will take deep copy of @properties and attach the copy to the + * platform device. The memory associated with properties will be freed when the + * platform device is released. + */ +int platform_device_add_properties(struct platform_device *pdev, + const struct property_entry *properties) +{ + return device_add_properties(&pdev->dev, properties); +} +EXPORT_SYMBOL_GPL(platform_device_add_properties); + +/** + * 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) +{ + u32 i; + int ret; + + if (!pdev) + return -EINVAL; + + if (!pdev->dev.parent) + pdev->dev.parent = &platform_bus; + + pdev->dev.bus = &platform_bus_type; + + switch (pdev->id) { + default: + dev_set_name(&pdev->dev, "%s.%d", pdev->name, pdev->id); + break; + case PLATFORM_DEVID_NONE: + dev_set_name(&pdev->dev, "%s", pdev->name); + break; + case PLATFORM_DEVID_AUTO: + /* + * Automatically allocated device ID. We mark it as such so + * that we remember it must be freed, and we append a suffix + * to avoid namespace collision with explicit IDs. + */ + ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL); + if (ret < 0) + goto err_out; + pdev->id = ret; + pdev->id_auto = true; + dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id); + break; + } + + for (i = 0; i < pdev->num_resources; i++) { + struct resource *p, *r = &pdev->resource[i]; + + if (r->name == NULL) + r->name = dev_name(&pdev->dev); + + p = r->parent; + if (!p) { + if (resource_type(r) == IORESOURCE_MEM) + p = &iomem_resource; + else if (resource_type(r) == IORESOURCE_IO) + p = &ioport_resource; + } + + if (p && insert_resource(p, r)) { + dev_err(&pdev->dev, "failed to claim resource %d: %pR\n", i, r); + ret = -EBUSY; + goto failed; + } + } + + pr_debug("Registering platform device '%s'. Parent at %s\n", + dev_name(&pdev->dev), dev_name(pdev->dev.parent)); + + ret = device_add(&pdev->dev); + if (ret == 0) + return ret; + + failed: + if (pdev->id_auto) { + ida_simple_remove(&platform_devid_ida, pdev->id); + pdev->id = PLATFORM_DEVID_AUTO; + } + + while (i--) { + struct resource *r = &pdev->resource[i]; + if (r->parent) + release_resource(r); + } + + err_out: + 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) +{ + u32 i; + + if (pdev) { + device_remove_properties(&pdev->dev); + device_del(&pdev->dev); + + if (pdev->id_auto) { + ida_simple_remove(&platform_devid_ida, pdev->id); + pdev->id = PLATFORM_DEVID_AUTO; + } + + for (i = 0; i < pdev->num_resources; i++) { + struct resource *r = &pdev->resource[i]; + if (r->parent) + 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); + arch_setup_pdev_archdata(pdev); + 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_full - add a platform-level device with + * resources and platform-specific data + * + * @pdevinfo: data used to create device + * + * Returns &struct platform_device pointer on success, or ERR_PTR() on error. + */ +struct platform_device *platform_device_register_full( + const struct platform_device_info *pdevinfo) +{ + int ret = -ENOMEM; + struct platform_device *pdev; + + pdev = platform_device_alloc(pdevinfo->name, pdevinfo->id); + if (!pdev) + goto err_alloc; + + pdev->dev.parent = pdevinfo->parent; + pdev->dev.fwnode = pdevinfo->fwnode; + + if (pdevinfo->dma_mask) { + /* + * This memory isn't freed when the device is put, + * I don't have a nice idea for that though. Conceptually + * dma_mask in struct device should not be a pointer. + * See http://thread.gmane.org/gmane.linux.kernel.pci/9081 + */ + pdev->dev.dma_mask = + kmalloc(sizeof(*pdev->dev.dma_mask), GFP_KERNEL); + if (!pdev->dev.dma_mask) + goto err; + + kmemleak_ignore(pdev->dev.dma_mask); + + *pdev->dev.dma_mask = pdevinfo->dma_mask; + pdev->dev.coherent_dma_mask = pdevinfo->dma_mask; + } + + ret = platform_device_add_resources(pdev, + pdevinfo->res, pdevinfo->num_res); + if (ret) + goto err; + + ret = platform_device_add_data(pdev, + pdevinfo->data, pdevinfo->size_data); + if (ret) + goto err; + + if (pdevinfo->properties) { + ret = platform_device_add_properties(pdev, + pdevinfo->properties); + if (ret) + goto err; + } + + ret = platform_device_add(pdev); + if (ret) { +err: + ACPI_COMPANION_SET(&pdev->dev, NULL); + kfree(pdev->dev.dma_mask); + +err_alloc: + platform_device_put(pdev); + return ERR_PTR(ret); + } + + return pdev; +} +EXPORT_SYMBOL_GPL(platform_device_register_full); + +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); + int ret; + + ret = of_clk_set_defaults(_dev->of_node, false); + if (ret < 0) + return ret; + + ret = dev_pm_domain_attach(_dev, true); + if (ret) + goto out; + + if (drv->probe) { + ret = drv->probe(dev); + if (ret) + dev_pm_domain_detach(_dev, true); + } + +out: + if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) { + dev_warn(_dev, "probe deferral not supported\n"); + ret = -ENXIO; + } + + return ret; +} + +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); + int ret = 0; + + if (drv->remove) + ret = drv->remove(dev); + dev_pm_domain_detach(_dev, true); + + return ret; +} + +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); + + if (drv->shutdown) + drv->shutdown(dev); +} + +/** + * __platform_driver_register - register a driver for platform-level devices + * @drv: platform driver structure + * @owner: owning module/driver + */ +int __platform_driver_register(struct platform_driver *drv, + struct module *owner) +{ + drv->driver.owner = owner; + drv->driver.bus = &platform_bus_type; + drv->driver.probe = platform_drv_probe; + drv->driver.remove = platform_drv_remove; + drv->driver.shutdown = platform_drv_shutdown; + + return driver_register(&drv->driver); +} +EXPORT_SYMBOL_GPL(__platform_driver_register); + +/** + * platform_driver_unregister - unregister a driver for platform-level devices + * @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 + * @module: module which will be the owner of the driver + * + * 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. + * + * Note that this is incompatible with deferred probing. + * + * 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 *), struct module *module) +{ + int retval, code; + + if (drv->driver.probe_type == PROBE_PREFER_ASYNCHRONOUS) { + pr_err("%s: drivers registered with %s can not be probed asynchronously\n", + drv->driver.name, __func__); + return -EINVAL; + } + + /* + * We have to run our probes synchronously because we check if + * we find any devices to bind to and exit with error if there + * are any. + */ + drv->driver.probe_type = PROBE_FORCE_SYNCHRONOUS; + + /* + * Prevent driver from requesting probe deferral to avoid further + * futile probe attempts. + */ + drv->prevent_deferred_probe = true; + + /* make sure driver won't have bind/unbind attributes */ + drv->driver.suppress_bind_attrs = true; + + /* temporary section violation during probe() */ + drv->probe = probe; + retval = code = __platform_driver_register(drv, module); + if (retval) + return retval; + + /* + * 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(&drv->driver.bus->p->klist_drivers.k_lock); + drv->probe = NULL; + if (code == 0 && list_empty(&drv->driver.p->klist_devices.k_list)) + retval = -ENODEV; + drv->driver.probe = platform_drv_probe_fail; + spin_unlock(&drv->driver.bus->p->klist_drivers.k_lock); + + if (code != retval) + platform_driver_unregister(drv); + return retval; +} +EXPORT_SYMBOL_GPL(__platform_driver_probe); + +/** + * __platform_create_bundle - register driver and create corresponding device + * @driver: platform driver structure + * @probe: the driver probe routine, probably from an __init section + * @res: set of resources that needs to be allocated for the device + * @n_res: number of resources + * @data: platform specific data for this platform device + * @size: size of platform specific data + * @module: module which will be the owner of the driver + * + * Use this in legacy-style modules that probe hardware directly and + * register a single platform device and corresponding platform driver. + * + * Returns &struct platform_device pointer on success, or ERR_PTR() on error. + */ +struct platform_device * __init_or_module __platform_create_bundle( + struct platform_driver *driver, + int (*probe)(struct platform_device *), + struct resource *res, unsigned int n_res, + const void *data, size_t size, struct module *module) +{ + struct platform_device *pdev; + int error; + + pdev = platform_device_alloc(driver->driver.name, -1); + if (!pdev) { + error = -ENOMEM; + goto err_out; + } + + error = platform_device_add_resources(pdev, res, n_res); + if (error) + goto err_pdev_put; + + error = platform_device_add_data(pdev, data, size); + if (error) + goto err_pdev_put; + + error = platform_device_add(pdev); + if (error) + goto err_pdev_put; + + error = __platform_driver_probe(driver, probe, module); + if (error) + goto err_pdev_del; + + return pdev; + +err_pdev_del: + platform_device_del(pdev); +err_pdev_put: + platform_device_put(pdev); +err_out: + return ERR_PTR(error); +} +EXPORT_SYMBOL_GPL(__platform_create_bundle); + +/** + * __platform_register_drivers - register an array of platform drivers + * @drivers: an array of drivers to register + * @count: the number of drivers to register + * @owner: module owning the drivers + * + * Registers platform drivers specified by an array. On failure to register a + * driver, all previously registered drivers will be unregistered. Callers of + * this API should use platform_unregister_drivers() to unregister drivers in + * the reverse order. + * + * Returns: 0 on success or a negative error code on failure. + */ +int __platform_register_drivers(struct platform_driver * const *drivers, + unsigned int count, struct module *owner) +{ + unsigned int i; + int err; + + for (i = 0; i < count; i++) { + pr_debug("registering platform driver %ps\n", drivers[i]); + + err = __platform_driver_register(drivers[i], owner); + if (err < 0) { + pr_err("failed to register platform driver %ps: %d\n", + drivers[i], err); + goto error; + } + } + + return 0; + +error: + while (i--) { + pr_debug("unregistering platform driver %ps\n", drivers[i]); + platform_driver_unregister(drivers[i]); + } + + return err; +} +EXPORT_SYMBOL_GPL(__platform_register_drivers); + +/** + * platform_unregister_drivers - unregister an array of platform drivers + * @drivers: an array of drivers to unregister + * @count: the number of drivers to unregister + * + * Unegisters platform drivers specified by an array. This is typically used + * to complement an earlier call to platform_register_drivers(). Drivers are + * unregistered in the reverse order in which they were registered. + */ +void platform_unregister_drivers(struct platform_driver * const *drivers, + unsigned int count) +{ + while (count--) { + pr_debug("unregistering platform driver %ps\n", drivers[count]); + platform_driver_unregister(drivers[count]); + } +} +EXPORT_SYMBOL_GPL(platform_unregister_drivers); + +/* 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; + + len = of_device_modalias(dev, buf, PAGE_SIZE); + if (len != -ENODEV) + return len; + + len = acpi_device_modalias(dev, buf, PAGE_SIZE -1); + if (len != -ENODEV) + return len; + + len = snprintf(buf, PAGE_SIZE, "platform:%s\n", pdev->name); + + return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len; +} +static DEVICE_ATTR_RO(modalias); + +static ssize_t driver_override_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct platform_device *pdev = to_platform_device(dev); + char *driver_override, *old, *cp; + + /* We need to keep extra room for a newline */ + if (count >= (PAGE_SIZE - 1)) + return -EINVAL; + + driver_override = kstrndup(buf, count, GFP_KERNEL); + if (!driver_override) + return -ENOMEM; + + cp = strchr(driver_override, '\n'); + if (cp) + *cp = '\0'; + + device_lock(dev); + old = pdev->driver_override; + if (strlen(driver_override)) { + pdev->driver_override = driver_override; + } else { + kfree(driver_override); + pdev->driver_override = NULL; + } + device_unlock(dev); + + kfree(old); + + return count; +} + +static ssize_t driver_override_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct platform_device *pdev = to_platform_device(dev); + ssize_t len; + + device_lock(dev); + len = sprintf(buf, "%s\n", pdev->driver_override); + device_unlock(dev); + return len; +} +static DEVICE_ATTR_RW(driver_override); + + +static struct attribute *platform_dev_attrs[] = { + &dev_attr_modalias.attr, + &dev_attr_driver_override.attr, + NULL, +}; +ATTRIBUTE_GROUPS(platform_dev); + +static int platform_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct platform_device *pdev = to_platform_device(dev); + int rc; + + /* Some devices have extra OF data and an OF-style MODALIAS */ + rc = of_device_uevent_modalias(dev, env); + if (rc != -ENODEV) + return rc; + + rc = acpi_device_uevent_modalias(dev, env); + if (rc != -ENODEV) + return rc; + + add_uevent_var(env, "MODALIAS=%s%s", PLATFORM_MODULE_PREFIX, + pdev->name); + return 0; +} + +static const struct platform_device_id *platform_match_id( + const struct platform_device_id *id, + struct platform_device *pdev) +{ + while (id->name[0]) { + if (strcmp(pdev->name, id->name) == 0) { + pdev->id_entry = id; + return id; + } + id++; + } + return NULL; +} + +/** + * 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 = to_platform_device(dev); + struct platform_driver *pdrv = to_platform_driver(drv); + + /* When driver_override is set, only bind to the matching driver */ + if (pdev->driver_override) + return !strcmp(pdev->driver_override, drv->name); + + /* Attempt an OF style match first */ + if (of_driver_match_device(dev, drv)) + return 1; + + /* Then try ACPI style match */ + if (acpi_driver_match_device(dev, drv)) + return 1; + + /* Then try to match against the id table */ + if (pdrv->id_table) + return platform_match_id(pdrv->id_table, pdev) != NULL; + + /* fall-back to driver name match */ + return (strcmp(pdev->name, drv->name) == 0); +} + +#ifdef CONFIG_PM_SLEEP + +static int platform_legacy_suspend(struct device *dev, pm_message_t mesg) +{ + struct platform_driver *pdrv = to_platform_driver(dev->driver); + struct platform_device *pdev = to_platform_device(dev); + int ret = 0; + + if (dev->driver && pdrv->suspend) + ret = pdrv->suspend(pdev, mesg); + + return ret; +} + +static int platform_legacy_resume(struct device *dev) +{ + struct platform_driver *pdrv = to_platform_driver(dev->driver); + struct platform_device *pdev = to_platform_device(dev); + int ret = 0; + + if (dev->driver && pdrv->resume) + ret = pdrv->resume(pdev); + + return ret; +} + +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_SUSPEND + +int platform_pm_suspend(struct device *dev) +{ + struct device_driver *drv = dev->driver; + int ret = 0; + + if (!drv) + return 0; + + if (drv->pm) { + if (drv->pm->suspend) + ret = drv->pm->suspend(dev); + } else { + ret = platform_legacy_suspend(dev, PMSG_SUSPEND); + } + + return ret; +} + +int platform_pm_resume(struct device *dev) +{ + struct device_driver *drv = dev->driver; + int ret = 0; + + if (!drv) + return 0; + + if (drv->pm) { + if (drv->pm->resume) + ret = drv->pm->resume(dev); + } else { + ret = platform_legacy_resume(dev); + } + + return ret; +} + +#endif /* CONFIG_SUSPEND */ + +#ifdef CONFIG_HIBERNATE_CALLBACKS + +int platform_pm_freeze(struct device *dev) +{ + struct device_driver *drv = dev->driver; + int ret = 0; + + if (!drv) + return 0; + + if (drv->pm) { + if (drv->pm->freeze) + ret = drv->pm->freeze(dev); + } else { + ret = platform_legacy_suspend(dev, PMSG_FREEZE); + } + + return ret; +} + +int platform_pm_thaw(struct device *dev) +{ + struct device_driver *drv = dev->driver; + int ret = 0; + + if (!drv) + return 0; + + if (drv->pm) { + if (drv->pm->thaw) + ret = drv->pm->thaw(dev); + } else { + ret = platform_legacy_resume(dev); + } + + return ret; +} + +int platform_pm_poweroff(struct device *dev) +{ + struct device_driver *drv = dev->driver; + int ret = 0; + + if (!drv) + return 0; + + if (drv->pm) { + if (drv->pm->poweroff) + ret = drv->pm->poweroff(dev); + } else { + ret = platform_legacy_suspend(dev, PMSG_HIBERNATE); + } + + return ret; +} + +int platform_pm_restore(struct device *dev) +{ + struct device_driver *drv = dev->driver; + int ret = 0; + + if (!drv) + return 0; + + if (drv->pm) { + if (drv->pm->restore) + ret = drv->pm->restore(dev); + } else { + ret = platform_legacy_resume(dev); + } + + return ret; +} + +#endif /* CONFIG_HIBERNATE_CALLBACKS */ + +int platform_dma_configure(struct device *dev) +{ + enum dev_dma_attr attr; + int ret = 0; + + if (dev->of_node) { + ret = of_dma_configure(dev, dev->of_node, true); + } else if (has_acpi_companion(dev)) { + attr = acpi_get_dma_attr(to_acpi_device_node(dev->fwnode)); + if (attr != DEV_DMA_NOT_SUPPORTED) + ret = acpi_dma_configure(dev, attr); + } + + return ret; +} + +static const struct dev_pm_ops platform_dev_pm_ops = { + .runtime_suspend = pm_generic_runtime_suspend, + .runtime_resume = pm_generic_runtime_resume, + USE_PLATFORM_PM_SLEEP_OPS +}; + +struct bus_type platform_bus_type = { + .name = "platform", + .dev_groups = platform_dev_groups, + .match = platform_match, + .uevent = platform_uevent, + .dma_configure = platform_dma_configure, + .pm = &platform_dev_pm_ops, +}; +EXPORT_SYMBOL_GPL(platform_bus_type); + +int __init platform_bus_init(void) +{ + int error; + + early_platform_cleanup(); + + error = device_register(&platform_bus); + if (error) { + put_device(&platform_bus); + return error; + } + error = bus_register(&platform_bus_type); + if (error) + device_unregister(&platform_bus); + of_platform_register_reconfig_notifier(); + 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; +} +EXPORT_SYMBOL_GPL(dma_get_required_mask); +#endif + +static __initdata LIST_HEAD(early_platform_driver_list); +static __initdata LIST_HEAD(early_platform_device_list); + +/** + * early_platform_driver_register - register early platform driver + * @epdrv: early_platform driver structure + * @buf: string passed from early_param() + * + * Helper function for early_platform_init() / early_platform_init_buffer() + */ +int __init early_platform_driver_register(struct early_platform_driver *epdrv, + char *buf) +{ + char *tmp; + int n; + + /* Simply add the driver to the end of the global list. + * Drivers will by default be put on the list in compiled-in order. + */ + if (!epdrv->list.next) { + INIT_LIST_HEAD(&epdrv->list); + list_add_tail(&epdrv->list, &early_platform_driver_list); + } + + /* If the user has specified device then make sure the driver + * gets prioritized. The driver of the last device specified on + * command line will be put first on the list. + */ + n = strlen(epdrv->pdrv->driver.name); + if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) { + list_move(&epdrv->list, &early_platform_driver_list); + + /* Allow passing parameters after device name */ + if (buf[n] == '\0' || buf[n] == ',') + epdrv->requested_id = -1; + else { + epdrv->requested_id = simple_strtoul(&buf[n + 1], + &tmp, 10); + + if (buf[n] != '.' || (tmp == &buf[n + 1])) { + epdrv->requested_id = EARLY_PLATFORM_ID_ERROR; + n = 0; + } else + n += strcspn(&buf[n + 1], ",") + 1; + } + + if (buf[n] == ',') + n++; + + if (epdrv->bufsize) { + memcpy(epdrv->buffer, &buf[n], + min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1)); + epdrv->buffer[epdrv->bufsize - 1] = '\0'; + } + } + + return 0; +} + +/** + * early_platform_add_devices - adds a number of early platform devices + * @devs: array of early platform devices to add + * @num: number of early platform devices in array + * + * Used by early architecture code to register early platform devices and + * their platform data. + */ +void __init early_platform_add_devices(struct platform_device **devs, int num) +{ + struct device *dev; + int i; + + /* simply add the devices to list */ + for (i = 0; i < num; i++) { + dev = &devs[i]->dev; + + if (!dev->devres_head.next) { + pm_runtime_early_init(dev); + INIT_LIST_HEAD(&dev->devres_head); + list_add_tail(&dev->devres_head, + &early_platform_device_list); + } + } +} + +/** + * early_platform_driver_register_all - register early platform drivers + * @class_str: string to identify early platform driver class + * + * Used by architecture code to register all early platform drivers + * for a certain class. If omitted then only early platform drivers + * with matching kernel command line class parameters will be registered. + */ +void __init early_platform_driver_register_all(char *class_str) +{ + /* The "class_str" parameter may or may not be present on the kernel + * command line. If it is present then there may be more than one + * matching parameter. + * + * Since we register our early platform drivers using early_param() + * we need to make sure that they also get registered in the case + * when the parameter is missing from the kernel command line. + * + * We use parse_early_options() to make sure the early_param() gets + * called at least once. The early_param() may be called more than + * once since the name of the preferred device may be specified on + * the kernel command line. early_platform_driver_register() handles + * this case for us. + */ + parse_early_options(class_str); +} + +/** + * early_platform_match - find early platform device matching driver + * @epdrv: early platform driver structure + * @id: id to match against + */ +static struct platform_device * __init +early_platform_match(struct early_platform_driver *epdrv, int id) +{ + struct platform_device *pd; + + list_for_each_entry(pd, &early_platform_device_list, dev.devres_head) + if (platform_match(&pd->dev, &epdrv->pdrv->driver)) + if (pd->id == id) + return pd; + + return NULL; +} + +/** + * early_platform_left - check if early platform driver has matching devices + * @epdrv: early platform driver structure + * @id: return true if id or above exists + */ +static int __init early_platform_left(struct early_platform_driver *epdrv, + int id) +{ + struct platform_device *pd; + + list_for_each_entry(pd, &early_platform_device_list, dev.devres_head) + if (platform_match(&pd->dev, &epdrv->pdrv->driver)) + if (pd->id >= id) + return 1; + + return 0; +} + +/** + * early_platform_driver_probe_id - probe drivers matching class_str and id + * @class_str: string to identify early platform driver class + * @id: id to match against + * @nr_probe: number of platform devices to successfully probe before exiting + */ +static int __init early_platform_driver_probe_id(char *class_str, + int id, + int nr_probe) +{ + struct early_platform_driver *epdrv; + struct platform_device *match; + int match_id; + int n = 0; + int left = 0; + + list_for_each_entry(epdrv, &early_platform_driver_list, list) { + /* only use drivers matching our class_str */ + if (strcmp(class_str, epdrv->class_str)) + continue; + + if (id == -2) { + match_id = epdrv->requested_id; + left = 1; + + } else { + match_id = id; + left += early_platform_left(epdrv, id); + + /* skip requested id */ + switch (epdrv->requested_id) { + case EARLY_PLATFORM_ID_ERROR: + case EARLY_PLATFORM_ID_UNSET: + break; + default: + if (epdrv->requested_id == id) + match_id = EARLY_PLATFORM_ID_UNSET; + } + } + + switch (match_id) { + case EARLY_PLATFORM_ID_ERROR: + pr_warn("%s: unable to parse %s parameter\n", + class_str, epdrv->pdrv->driver.name); + /* fall-through */ + case EARLY_PLATFORM_ID_UNSET: + match = NULL; + break; + default: + match = early_platform_match(epdrv, match_id); + } + + if (match) { + /* + * Set up a sensible init_name to enable + * dev_name() and others to be used before the + * rest of the driver core is initialized. + */ + if (!match->dev.init_name && slab_is_available()) { + if (match->id != -1) + match->dev.init_name = + kasprintf(GFP_KERNEL, "%s.%d", + match->name, + match->id); + else + match->dev.init_name = + kasprintf(GFP_KERNEL, "%s", + match->name); + + if (!match->dev.init_name) + return -ENOMEM; + } + + if (epdrv->pdrv->probe(match)) + pr_warn("%s: unable to probe %s early.\n", + class_str, match->name); + else + n++; + } + + if (n >= nr_probe) + break; + } + + if (left) + return n; + else + return -ENODEV; +} + +/** + * early_platform_driver_probe - probe a class of registered drivers + * @class_str: string to identify early platform driver class + * @nr_probe: number of platform devices to successfully probe before exiting + * @user_only: only probe user specified early platform devices + * + * Used by architecture code to probe registered early platform drivers + * within a certain class. For probe to happen a registered early platform + * device matching a registered early platform driver is needed. + */ +int __init early_platform_driver_probe(char *class_str, + int nr_probe, + int user_only) +{ + int k, n, i; + + n = 0; + for (i = -2; n < nr_probe; i++) { + k = early_platform_driver_probe_id(class_str, i, nr_probe - n); + + if (k < 0) + break; + + n += k; + + if (user_only) + break; + } + + return n; +} + +/** + * early_platform_cleanup - clean up early platform code + */ +void __init early_platform_cleanup(void) +{ + struct platform_device *pd, *pd2; + + /* clean up the devres list used to chain devices */ + list_for_each_entry_safe(pd, pd2, &early_platform_device_list, + dev.devres_head) { + list_del(&pd->dev.devres_head); + memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head)); + } +} + |