1 files changed, 730 insertions, 0 deletions

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
new file mode 100644
index 00000000..5401814c
--- /dev/null
+++ b/drivers/base/firmware_class.c
@@ -0,0 +1,730 @@
+/*
+ * 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/workqueue.h>
+#include <linux/highmem.h>
+#include <linux/firmware.h>
+#include <linux/slab.h>
+#include <linux/sched.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 */
+
+static inline long firmware_loading_timeout(void)
+{
+	return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
+}
+
+/* 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;
+
+	mutex_lock(&fw_lock);
+
+	if (!fw_priv->fw)
+		goto out;
+
+	switch (loading) {
+	case 1:
+		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);
+		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;
+	}
+out:
+	mutex_unlock(&fw_lock);
+	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;
+
+	fw_priv = kzalloc(sizeof(*fw_priv) + strlen(fw_name) + 1 , GFP_KERNEL);
+	if (!fw_priv) {
+		dev_err(device, "%s: kmalloc failed\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	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;
+
+	return fw_priv;
+}
+
+static struct firmware_priv *
+_request_firmware_prepare(const struct firmware **firmware_p, const char *name,
+			  struct device *device, bool uevent, bool nowait)
+{
+	struct firmware *firmware;
+	struct firmware_priv *fw_priv;
+
+	if (!firmware_p)
+		return ERR_PTR(-EINVAL);
+
+	*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
+	if (!firmware) {
+		dev_err(device, "%s: kmalloc(struct firmware) failed\n",
+			__func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	if (fw_get_builtin_firmware(firmware, name)) {
+		dev_dbg(device, "firmware: using built-in firmware %s\n", name);
+		return NULL;
+	}
+
+	fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
+	if (IS_ERR(fw_priv)) {
+		release_firmware(firmware);
+		*firmware_p = NULL;
+	}
+	return fw_priv;
+}
+
+static void _request_firmware_cleanup(const struct firmware **firmware_p)
+{
+	release_firmware(*firmware_p);
+	*firmware_p = NULL;
+}
+
+static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
+				  long timeout)
+{
+	int retval = 0;
+	struct device *f_dev = &fw_priv->dev;
+
+	dev_set_uevent_suppress(f_dev, true);
+
+	/* Need to pin this module until class device is destroyed */
+	__module_get(THIS_MODULE);
+
+	retval = device_add(f_dev);
+	if (retval) {
+		dev_err(f_dev, "%s: device_register failed\n", __func__);
+		goto err_put_dev;
+	}
+
+	retval = device_create_bin_file(f_dev, &firmware_attr_data);
+	if (retval) {
+		dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
+		goto err_del_dev;
+	}
+
+	retval = device_create_file(f_dev, &dev_attr_loading);
+	if (retval) {
+		dev_err(f_dev, "%s: device_create_file failed\n", __func__);
+		goto err_del_bin_attr;
+	}
+
+	if (uevent) {
+		dev_set_uevent_suppress(f_dev, false);
+		dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_id);
+		if (timeout != MAX_SCHEDULE_TIMEOUT)
+			mod_timer(&fw_priv->timeout,
+				  round_jiffies_up(jiffies + timeout));
+
+		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);
+
+	device_remove_file(f_dev, &dev_attr_loading);
+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);
+	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)
+{
+	struct firmware_priv *fw_priv;
+	int ret;
+
+	fw_priv = _request_firmware_prepare(firmware_p, name, device, true,
+					    false);
+	if (IS_ERR_OR_NULL(fw_priv))
+		return PTR_RET(fw_priv);
+
+	ret = usermodehelper_read_trylock();
+	if (WARN_ON(ret)) {
+		dev_err(device, "firmware: %s will not be loaded\n", name);
+	} else {
+		ret = _request_firmware_load(fw_priv, true,
+					firmware_loading_timeout());
+		usermodehelper_read_unlock();
+	}
+	if (ret)
+		_request_firmware_cleanup(firmware_p);
+
+	return ret;
+}
+
+/**
+ * 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);
+	bool uevent;
+};
+
+static void request_firmware_work_func(struct work_struct *work)
+{
+	struct firmware_work *fw_work;
+	const struct firmware *fw;
+	struct firmware_priv *fw_priv;
+	long timeout;
+	int ret;
+
+	fw_work = container_of(work, struct firmware_work, work);
+	fw_priv = _request_firmware_prepare(&fw, fw_work->name, fw_work->device,
+			fw_work->uevent, true);
+	if (IS_ERR_OR_NULL(fw_priv)) {
+		ret = PTR_RET(fw_priv);
+		goto out;
+	}
+
+	timeout = usermodehelper_read_lock_wait(firmware_loading_timeout());
+	if (timeout) {
+		ret = _request_firmware_load(fw_priv, fw_work->uevent, timeout);
+		usermodehelper_read_unlock();
+	} else {
+		dev_dbg(fw_work->device, "firmware: %s loading timed out\n",
+			fw_work->name);
+		ret = -EAGAIN;
+	}
+	if (ret)
+		_request_firmware_cleanup(&fw);
+
+ out:
+	fw_work->cont(fw, fw_work->context);
+
+	module_put(fw_work->module);
+	kfree(fw_work);
+}
+
+/**
+ * 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, bool uevent,
+	const char *name, struct device *device, gfp_t gfp, void *context,
+	void (*cont)(const struct firmware *fw, void *context))
+{
+	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;
+	}
+
+	INIT_WORK(&fw_work->work, request_firmware_work_func);
+	schedule_work(&fw_work->work);
+	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);