| /* |
| * firmware_class.c - Multi purpose firmware loading support |
| * |
| * Copyright (c) 2003 Manuel Estrada Sainz |
| * |
| * Please see Documentation/firmware_class/ for more information. |
| * |
| */ |
| |
| #include <linux/capability.h> |
| #include <linux/device.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/timer.h> |
| #include <linux/vmalloc.h> |
| #include <linux/interrupt.h> |
| #include <linux/bitops.h> |
| #include <linux/mutex.h> |
| #include <linux/kthread.h> |
| #include <linux/highmem.h> |
| #include <linux/firmware.h> |
| #include <linux/slab.h> |
| |
| #define to_dev(obj) container_of(obj, struct device, kobj) |
| |
| MODULE_AUTHOR("Manuel Estrada Sainz"); |
| MODULE_DESCRIPTION("Multi purpose firmware loading support"); |
| MODULE_LICENSE("GPL"); |
| |
| /* Builtin firmware support */ |
| |
| #ifdef CONFIG_FW_LOADER |
| |
| extern struct builtin_fw __start_builtin_fw[]; |
| extern struct builtin_fw __end_builtin_fw[]; |
| |
| static bool fw_get_builtin_firmware(struct firmware *fw, const char *name) |
| { |
| struct builtin_fw *b_fw; |
| |
| for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) { |
| if (strcmp(name, b_fw->name) == 0) { |
| fw->size = b_fw->size; |
| fw->data = b_fw->data; |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| static bool fw_is_builtin_firmware(const struct firmware *fw) |
| { |
| struct builtin_fw *b_fw; |
| |
| for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) |
| if (fw->data == b_fw->data) |
| return true; |
| |
| return false; |
| } |
| |
| #else /* Module case - no builtin firmware support */ |
| |
| static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name) |
| { |
| return false; |
| } |
| |
| static inline bool fw_is_builtin_firmware(const struct firmware *fw) |
| { |
| return false; |
| } |
| #endif |
| |
| enum { |
| FW_STATUS_LOADING, |
| FW_STATUS_DONE, |
| FW_STATUS_ABORT, |
| }; |
| |
| static int loading_timeout = 60; /* In seconds */ |
| |
| /* fw_lock could be moved to 'struct firmware_priv' but since it is just |
| * guarding for corner cases a global lock should be OK */ |
| static DEFINE_MUTEX(fw_lock); |
| |
| struct firmware_priv { |
| struct completion completion; |
| struct firmware *fw; |
| unsigned long status; |
| struct page **pages; |
| int nr_pages; |
| int page_array_size; |
| struct timer_list timeout; |
| struct device dev; |
| bool nowait; |
| char fw_id[]; |
| }; |
| |
| static struct firmware_priv *to_firmware_priv(struct device *dev) |
| { |
| return container_of(dev, struct firmware_priv, dev); |
| } |
| |
| static void fw_load_abort(struct firmware_priv *fw_priv) |
| { |
| set_bit(FW_STATUS_ABORT, &fw_priv->status); |
| wmb(); |
| complete(&fw_priv->completion); |
| } |
| |
| static ssize_t firmware_timeout_show(struct class *class, |
| struct class_attribute *attr, |
| char *buf) |
| { |
| return sprintf(buf, "%d\n", loading_timeout); |
| } |
| |
| /** |
| * firmware_timeout_store - set number of seconds to wait for firmware |
| * @class: device class pointer |
| * @attr: device attribute pointer |
| * @buf: buffer to scan for timeout value |
| * @count: number of bytes in @buf |
| * |
| * Sets the number of seconds to wait for the firmware. Once |
| * this expires an error will be returned to the driver and no |
| * firmware will be provided. |
| * |
| * Note: zero means 'wait forever'. |
| **/ |
| static ssize_t firmware_timeout_store(struct class *class, |
| struct class_attribute *attr, |
| const char *buf, size_t count) |
| { |
| loading_timeout = simple_strtol(buf, NULL, 10); |
| if (loading_timeout < 0) |
| loading_timeout = 0; |
| |
| return count; |
| } |
| |
| static struct class_attribute firmware_class_attrs[] = { |
| __ATTR(timeout, S_IWUSR | S_IRUGO, |
| firmware_timeout_show, firmware_timeout_store), |
| __ATTR_NULL |
| }; |
| |
| static void fw_dev_release(struct device *dev) |
| { |
| struct firmware_priv *fw_priv = to_firmware_priv(dev); |
| int i; |
| |
| for (i = 0; i < fw_priv->nr_pages; i++) |
| __free_page(fw_priv->pages[i]); |
| kfree(fw_priv->pages); |
| kfree(fw_priv); |
| |
| module_put(THIS_MODULE); |
| } |
| |
| static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env) |
| { |
| struct firmware_priv *fw_priv = to_firmware_priv(dev); |
| |
| if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->fw_id)) |
| return -ENOMEM; |
| if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout)) |
| return -ENOMEM; |
| if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait)) |
| return -ENOMEM; |
| |
| return 0; |
| } |
| |
| static struct class firmware_class = { |
| .name = "firmware", |
| .class_attrs = firmware_class_attrs, |
| .dev_uevent = firmware_uevent, |
| .dev_release = fw_dev_release, |
| }; |
| |
| static ssize_t firmware_loading_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct firmware_priv *fw_priv = to_firmware_priv(dev); |
| int loading = test_bit(FW_STATUS_LOADING, &fw_priv->status); |
| |
| return sprintf(buf, "%d\n", loading); |
| } |
| |
| static void firmware_free_data(const struct firmware *fw) |
| { |
| int i; |
| vunmap(fw->data); |
| if (fw->pages) { |
| for (i = 0; i < PFN_UP(fw->size); i++) |
| __free_page(fw->pages[i]); |
| kfree(fw->pages); |
| } |
| } |
| |
| /* Some architectures don't have PAGE_KERNEL_RO */ |
| #ifndef PAGE_KERNEL_RO |
| #define PAGE_KERNEL_RO PAGE_KERNEL |
| #endif |
| /** |
| * firmware_loading_store - set value in the 'loading' control file |
| * @dev: device pointer |
| * @attr: device attribute pointer |
| * @buf: buffer to scan for loading control value |
| * @count: number of bytes in @buf |
| * |
| * The relevant values are: |
| * |
| * 1: Start a load, discarding any previous partial load. |
| * 0: Conclude the load and hand the data to the driver code. |
| * -1: Conclude the load with an error and discard any written data. |
| **/ |
| static ssize_t firmware_loading_store(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t count) |
| { |
| struct firmware_priv *fw_priv = to_firmware_priv(dev); |
| int loading = simple_strtol(buf, NULL, 10); |
| int i; |
| |
| switch (loading) { |
| case 1: |
| mutex_lock(&fw_lock); |
| if (!fw_priv->fw) { |
| mutex_unlock(&fw_lock); |
| break; |
| } |
| firmware_free_data(fw_priv->fw); |
| memset(fw_priv->fw, 0, sizeof(struct firmware)); |
| /* If the pages are not owned by 'struct firmware' */ |
| for (i = 0; i < fw_priv->nr_pages; i++) |
| __free_page(fw_priv->pages[i]); |
| kfree(fw_priv->pages); |
| fw_priv->pages = NULL; |
| fw_priv->page_array_size = 0; |
| fw_priv->nr_pages = 0; |
| set_bit(FW_STATUS_LOADING, &fw_priv->status); |
| mutex_unlock(&fw_lock); |
| break; |
| case 0: |
| if (test_bit(FW_STATUS_LOADING, &fw_priv->status)) { |
| vunmap(fw_priv->fw->data); |
| fw_priv->fw->data = vmap(fw_priv->pages, |
| fw_priv->nr_pages, |
| 0, PAGE_KERNEL_RO); |
| if (!fw_priv->fw->data) { |
| dev_err(dev, "%s: vmap() failed\n", __func__); |
| goto err; |
| } |
| /* Pages are now owned by 'struct firmware' */ |
| fw_priv->fw->pages = fw_priv->pages; |
| fw_priv->pages = NULL; |
| |
| fw_priv->page_array_size = 0; |
| fw_priv->nr_pages = 0; |
| complete(&fw_priv->completion); |
| clear_bit(FW_STATUS_LOADING, &fw_priv->status); |
| break; |
| } |
| /* fallthrough */ |
| default: |
| dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading); |
| /* fallthrough */ |
| case -1: |
| err: |
| fw_load_abort(fw_priv); |
| break; |
| } |
| |
| return count; |
| } |
| |
| static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store); |
| |
| static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj, |
| struct bin_attribute *bin_attr, |
| char *buffer, loff_t offset, size_t count) |
| { |
| struct device *dev = to_dev(kobj); |
| struct firmware_priv *fw_priv = to_firmware_priv(dev); |
| struct firmware *fw; |
| ssize_t ret_count; |
| |
| mutex_lock(&fw_lock); |
| fw = fw_priv->fw; |
| if (!fw || test_bit(FW_STATUS_DONE, &fw_priv->status)) { |
| ret_count = -ENODEV; |
| goto out; |
| } |
| if (offset > fw->size) { |
| ret_count = 0; |
| goto out; |
| } |
| if (count > fw->size - offset) |
| count = fw->size - offset; |
| |
| ret_count = count; |
| |
| while (count) { |
| void *page_data; |
| int page_nr = offset >> PAGE_SHIFT; |
| int page_ofs = offset & (PAGE_SIZE-1); |
| int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count); |
| |
| page_data = kmap(fw_priv->pages[page_nr]); |
| |
| memcpy(buffer, page_data + page_ofs, page_cnt); |
| |
| kunmap(fw_priv->pages[page_nr]); |
| buffer += page_cnt; |
| offset += page_cnt; |
| count -= page_cnt; |
| } |
| out: |
| mutex_unlock(&fw_lock); |
| return ret_count; |
| } |
| |
| static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size) |
| { |
| int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT; |
| |
| /* If the array of pages is too small, grow it... */ |
| if (fw_priv->page_array_size < pages_needed) { |
| int new_array_size = max(pages_needed, |
| fw_priv->page_array_size * 2); |
| struct page **new_pages; |
| |
| new_pages = kmalloc(new_array_size * sizeof(void *), |
| GFP_KERNEL); |
| if (!new_pages) { |
| fw_load_abort(fw_priv); |
| return -ENOMEM; |
| } |
| memcpy(new_pages, fw_priv->pages, |
| fw_priv->page_array_size * sizeof(void *)); |
| memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) * |
| (new_array_size - fw_priv->page_array_size)); |
| kfree(fw_priv->pages); |
| fw_priv->pages = new_pages; |
| fw_priv->page_array_size = new_array_size; |
| } |
| |
| while (fw_priv->nr_pages < pages_needed) { |
| fw_priv->pages[fw_priv->nr_pages] = |
| alloc_page(GFP_KERNEL | __GFP_HIGHMEM); |
| |
| if (!fw_priv->pages[fw_priv->nr_pages]) { |
| fw_load_abort(fw_priv); |
| return -ENOMEM; |
| } |
| fw_priv->nr_pages++; |
| } |
| return 0; |
| } |
| |
| /** |
| * firmware_data_write - write method for firmware |
| * @filp: open sysfs file |
| * @kobj: kobject for the device |
| * @bin_attr: bin_attr structure |
| * @buffer: buffer being written |
| * @offset: buffer offset for write in total data store area |
| * @count: buffer size |
| * |
| * Data written to the 'data' attribute will be later handed to |
| * the driver as a firmware image. |
| **/ |
| static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj, |
| struct bin_attribute *bin_attr, |
| char *buffer, loff_t offset, size_t count) |
| { |
| struct device *dev = to_dev(kobj); |
| struct firmware_priv *fw_priv = to_firmware_priv(dev); |
| struct firmware *fw; |
| ssize_t retval; |
| |
| if (!capable(CAP_SYS_RAWIO)) |
| return -EPERM; |
| |
| mutex_lock(&fw_lock); |
| fw = fw_priv->fw; |
| if (!fw || test_bit(FW_STATUS_DONE, &fw_priv->status)) { |
| retval = -ENODEV; |
| goto out; |
| } |
| retval = fw_realloc_buffer(fw_priv, offset + count); |
| if (retval) |
| goto out; |
| |
| retval = count; |
| |
| while (count) { |
| void *page_data; |
| int page_nr = offset >> PAGE_SHIFT; |
| int page_ofs = offset & (PAGE_SIZE - 1); |
| int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count); |
| |
| page_data = kmap(fw_priv->pages[page_nr]); |
| |
| memcpy(page_data + page_ofs, buffer, page_cnt); |
| |
| kunmap(fw_priv->pages[page_nr]); |
| buffer += page_cnt; |
| offset += page_cnt; |
| count -= page_cnt; |
| } |
| |
| fw->size = max_t(size_t, offset, fw->size); |
| out: |
| mutex_unlock(&fw_lock); |
| return retval; |
| } |
| |
| static struct bin_attribute firmware_attr_data = { |
| .attr = { .name = "data", .mode = 0644 }, |
| .size = 0, |
| .read = firmware_data_read, |
| .write = firmware_data_write, |
| }; |
| |
| static void firmware_class_timeout(u_long data) |
| { |
| struct firmware_priv *fw_priv = (struct firmware_priv *) data; |
| |
| fw_load_abort(fw_priv); |
| } |
| |
| static struct firmware_priv * |
| fw_create_instance(struct firmware *firmware, const char *fw_name, |
| struct device *device, bool uevent, bool nowait) |
| { |
| struct firmware_priv *fw_priv; |
| struct device *f_dev; |
| int error; |
| |
| fw_priv = kzalloc(sizeof(*fw_priv) + strlen(fw_name) + 1 , GFP_KERNEL); |
| if (!fw_priv) { |
| dev_err(device, "%s: kmalloc failed\n", __func__); |
| error = -ENOMEM; |
| goto err_out; |
| } |
| |
| fw_priv->fw = firmware; |
| fw_priv->nowait = nowait; |
| strcpy(fw_priv->fw_id, fw_name); |
| init_completion(&fw_priv->completion); |
| setup_timer(&fw_priv->timeout, |
| firmware_class_timeout, (u_long) fw_priv); |
| |
| f_dev = &fw_priv->dev; |
| |
| device_initialize(f_dev); |
| dev_set_name(f_dev, "%s", dev_name(device)); |
| f_dev->parent = device; |
| f_dev->class = &firmware_class; |
| |
| dev_set_uevent_suppress(f_dev, true); |
| |
| /* Need to pin this module until class device is destroyed */ |
| __module_get(THIS_MODULE); |
| |
| error = device_add(f_dev); |
| if (error) { |
| dev_err(device, "%s: device_register failed\n", __func__); |
| goto err_put_dev; |
| } |
| |
| error = device_create_bin_file(f_dev, &firmware_attr_data); |
| if (error) { |
| dev_err(device, "%s: sysfs_create_bin_file failed\n", __func__); |
| goto err_del_dev; |
| } |
| |
| error = device_create_file(f_dev, &dev_attr_loading); |
| if (error) { |
| dev_err(device, "%s: device_create_file failed\n", __func__); |
| goto err_del_bin_attr; |
| } |
| |
| if (uevent) |
| dev_set_uevent_suppress(f_dev, false); |
| |
| return fw_priv; |
| |
| err_del_bin_attr: |
| device_remove_bin_file(f_dev, &firmware_attr_data); |
| err_del_dev: |
| device_del(f_dev); |
| err_put_dev: |
| put_device(f_dev); |
| err_out: |
| return ERR_PTR(error); |
| } |
| |
| static void fw_destroy_instance(struct firmware_priv *fw_priv) |
| { |
| struct device *f_dev = &fw_priv->dev; |
| |
| device_remove_file(f_dev, &dev_attr_loading); |
| device_remove_bin_file(f_dev, &firmware_attr_data); |
| device_unregister(f_dev); |
| } |
| |
| static int _request_firmware(const struct firmware **firmware_p, |
| const char *name, struct device *device, |
| bool uevent, bool nowait) |
| { |
| struct firmware_priv *fw_priv; |
| struct firmware *firmware; |
| int retval = 0; |
| |
| if (!firmware_p) |
| return -EINVAL; |
| |
| *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL); |
| if (!firmware) { |
| dev_err(device, "%s: kmalloc(struct firmware) failed\n", |
| __func__); |
| retval = -ENOMEM; |
| goto out; |
| } |
| |
| if (fw_get_builtin_firmware(firmware, name)) { |
| dev_dbg(device, "firmware: using built-in firmware %s\n", name); |
| return 0; |
| } |
| |
| if (uevent) |
| dev_dbg(device, "firmware: requesting %s\n", name); |
| |
| fw_priv = fw_create_instance(firmware, name, device, uevent, nowait); |
| if (IS_ERR(fw_priv)) { |
| retval = PTR_ERR(fw_priv); |
| goto out; |
| } |
| |
| if (uevent) { |
| if (loading_timeout > 0) |
| mod_timer(&fw_priv->timeout, |
| round_jiffies_up(jiffies + |
| loading_timeout * HZ)); |
| |
| kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD); |
| } |
| |
| wait_for_completion(&fw_priv->completion); |
| |
| set_bit(FW_STATUS_DONE, &fw_priv->status); |
| del_timer_sync(&fw_priv->timeout); |
| |
| mutex_lock(&fw_lock); |
| if (!fw_priv->fw->size || test_bit(FW_STATUS_ABORT, &fw_priv->status)) |
| retval = -ENOENT; |
| fw_priv->fw = NULL; |
| mutex_unlock(&fw_lock); |
| |
| fw_destroy_instance(fw_priv); |
| |
| out: |
| if (retval) { |
| release_firmware(firmware); |
| firmware_p = NULL; |
| } |
| |
| return retval; |
| } |
| |
| /** |
| * request_firmware: - send firmware request and wait for it |
| * @firmware_p: pointer to firmware image |
| * @name: name of firmware file |
| * @device: device for which firmware is being loaded |
| * |
| * @firmware_p will be used to return a firmware image by the name |
| * of @name for device @device. |
| * |
| * Should be called from user context where sleeping is allowed. |
| * |
| * @name will be used as $FIRMWARE in the uevent environment and |
| * should be distinctive enough not to be confused with any other |
| * firmware image for this or any other device. |
| **/ |
| int |
| request_firmware(const struct firmware **firmware_p, const char *name, |
| struct device *device) |
| { |
| int uevent = 1; |
| return _request_firmware(firmware_p, name, device, uevent, false); |
| } |
| |
| /** |
| * release_firmware: - release the resource associated with a firmware image |
| * @fw: firmware resource to release |
| **/ |
| void release_firmware(const struct firmware *fw) |
| { |
| if (fw) { |
| if (!fw_is_builtin_firmware(fw)) |
| firmware_free_data(fw); |
| kfree(fw); |
| } |
| } |
| |
| /* Async support */ |
| struct firmware_work { |
| struct work_struct work; |
| struct module *module; |
| const char *name; |
| struct device *device; |
| void *context; |
| void (*cont)(const struct firmware *fw, void *context); |
| int uevent; |
| }; |
| |
| static int request_firmware_work_func(void *arg) |
| { |
| struct firmware_work *fw_work = arg; |
| const struct firmware *fw; |
| int ret; |
| |
| if (!arg) { |
| WARN_ON(1); |
| return 0; |
| } |
| |
| ret = _request_firmware(&fw, fw_work->name, fw_work->device, |
| fw_work->uevent, true); |
| fw_work->cont(fw, fw_work->context); |
| |
| module_put(fw_work->module); |
| kfree(fw_work); |
| |
| return ret; |
| } |
| |
| /** |
| * request_firmware_nowait - asynchronous version of request_firmware |
| * @module: module requesting the firmware |
| * @uevent: sends uevent to copy the firmware image if this flag |
| * is non-zero else the firmware copy must be done manually. |
| * @name: name of firmware file |
| * @device: device for which firmware is being loaded |
| * @gfp: allocation flags |
| * @context: will be passed over to @cont, and |
| * @fw may be %NULL if firmware request fails. |
| * @cont: function will be called asynchronously when the firmware |
| * request is over. |
| * |
| * Asynchronous variant of request_firmware() for user contexts where |
| * it is not possible to sleep for long time. It can't be called |
| * in atomic contexts. |
| **/ |
| int |
| request_firmware_nowait( |
| struct module *module, int uevent, |
| const char *name, struct device *device, gfp_t gfp, void *context, |
| void (*cont)(const struct firmware *fw, void *context)) |
| { |
| struct task_struct *task; |
| struct firmware_work *fw_work; |
| |
| fw_work = kzalloc(sizeof (struct firmware_work), gfp); |
| if (!fw_work) |
| return -ENOMEM; |
| |
| fw_work->module = module; |
| fw_work->name = name; |
| fw_work->device = device; |
| fw_work->context = context; |
| fw_work->cont = cont; |
| fw_work->uevent = uevent; |
| |
| if (!try_module_get(module)) { |
| kfree(fw_work); |
| return -EFAULT; |
| } |
| |
| task = kthread_run(request_firmware_work_func, fw_work, |
| "firmware/%s", name); |
| if (IS_ERR(task)) { |
| fw_work->cont(NULL, fw_work->context); |
| module_put(fw_work->module); |
| kfree(fw_work); |
| return PTR_ERR(task); |
| } |
| |
| return 0; |
| } |
| |
| static int __init firmware_class_init(void) |
| { |
| return class_register(&firmware_class); |
| } |
| |
| static void __exit firmware_class_exit(void) |
| { |
| class_unregister(&firmware_class); |
| } |
| |
| fs_initcall(firmware_class_init); |
| module_exit(firmware_class_exit); |
| |
| EXPORT_SYMBOL(release_firmware); |
| EXPORT_SYMBOL(request_firmware); |
| EXPORT_SYMBOL(request_firmware_nowait); |