arch/arm/mach-msm/peripheral-loader.c - fp2-dev/kernel/msm - Gitiles

 /* Copyright (c) 2010-2012, Code Aurora Forum. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
  * only version 2 as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  */

 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/device.h>
 #include <linux/firmware.h>
 #include <linux/io.h>
 #include <linux/debugfs.h>
 #include <linux/elf.h>
 #include <linux/mutex.h>
 #include <linux/memblock.h>
 #include <linux/slab.h>

 #include <asm/uaccess.h>
 #include <asm/setup.h>

 #include "peripheral-loader.h"

 struct pil_device {
 	struct pil_desc *desc;
 	int count;
 	struct mutex lock;
 	struct list_head list;
 };

 static DEFINE_MUTEX(pil_list_lock);
 static LIST_HEAD(pil_list);

 static struct pil_device *__find_peripheral(const char *str)
 {
 	struct pil_device *dev;

 	list_for_each_entry(dev, &pil_list, list)
 		if (!strcmp(dev->desc->name, str))
 			return dev;
 	return NULL;
 }

 static struct pil_device *find_peripheral(const char *str)
 {
 	struct pil_device *dev;

 	if (!str)
 		return NULL;

 	mutex_lock(&pil_list_lock);
 	dev = __find_peripheral(str);
 	mutex_unlock(&pil_list_lock);

 	return dev;
 }

 #define IOMAP_SIZE SZ_4M

 static int load_segment(const struct elf32_phdr *phdr, unsigned num,
 		struct pil_device *pil)
 {
 	int ret, count, paddr;
 	char fw_name[30];
 	const struct firmware *fw = NULL;
 	const u8 *data;

 	if (memblock_is_region_memory(phdr->p_paddr, phdr->p_memsz)) {
 		dev_err(pil->desc->dev, "Kernel memory would be overwritten");
 		return -EPERM;
 	}

 	if (phdr->p_filesz) {
 		snprintf(fw_name, ARRAY_SIZE(fw_name), "%s.b%02d",
 				pil->desc->name, num);
 		ret = request_firmware(&fw, fw_name, pil->desc->dev);
 		if (ret) {
 			dev_err(pil->desc->dev, "Failed to locate blob %s\n",
 					fw_name);
 			return ret;
 		}

 		if (fw->size != phdr->p_filesz) {
 			dev_err(pil->desc->dev,
 				"Blob size %u doesn't match %u\n", fw->size,
 				phdr->p_filesz);
 			ret = -EPERM;
 			goto release_fw;
 		}
 	}

 	/* Load the segment into memory */
 	count = phdr->p_filesz;
 	paddr = phdr->p_paddr;
 	data = fw ? fw->data : NULL;
 	while (count > 0) {
 		int size;
 		u8 __iomem *buf;

 		size = min_t(size_t, IOMAP_SIZE, count);
 		buf = ioremap(paddr, size);
 		if (!buf) {
 			dev_err(pil->desc->dev, "Failed to map memory\n");
 			ret = -ENOMEM;
 			goto release_fw;
 		}
 		memcpy(buf, data, size);
 		iounmap(buf);

 		count -= size;
 		paddr += size;
 		data += size;
 	}

 	/* Zero out trailing memory */
 	count = phdr->p_memsz - phdr->p_filesz;
 	while (count > 0) {
 		int size;
 		u8 __iomem *buf;

 		size = min_t(size_t, IOMAP_SIZE, count);
 		buf = ioremap(paddr, size);
 		if (!buf) {
 			dev_err(pil->desc->dev, "Failed to map memory\n");
 			ret = -ENOMEM;
 			goto release_fw;
 		}
 		memset(buf, 0, size);
 		iounmap(buf);

 		count -= size;
 		paddr += size;
 	}

 	ret = pil->desc->ops->verify_blob(pil->desc, phdr->p_paddr,
 					  phdr->p_memsz);
 	if (ret)
 		dev_err(pil->desc->dev, "Blob %u failed verification\n", num);

 release_fw:
 	release_firmware(fw);
 	return ret;
 }

 #define segment_is_hash(flag) (((flag) & (0x7 << 24)) == (0x2 << 24))

 static int segment_is_loadable(const struct elf32_phdr *p)
 {
 	return (p->p_type & PT_LOAD) && !segment_is_hash(p->p_flags);
 }

 static int load_image(struct pil_device *pil)
 {
 	int i, ret;
 	char fw_name[30];
 	struct elf32_hdr *ehdr;
 	const struct elf32_phdr *phdr;
 	const struct firmware *fw;

 	snprintf(fw_name, sizeof(fw_name), "%s.mdt", pil->desc->name);
 	ret = request_firmware(&fw, fw_name, pil->desc->dev);
 	if (ret) {
 		dev_err(pil->desc->dev, "Failed to locate %s\n", fw_name);
 		goto out;
 	}

 	if (fw->size < sizeof(*ehdr)) {
 		dev_err(pil->desc->dev, "Not big enough to be an elf header\n");
 		ret = -EIO;
 		goto release_fw;
 	}

 	ehdr = (struct elf32_hdr *)fw->data;
 	if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {
 		dev_err(pil->desc->dev, "Not an elf header\n");
 		ret = -EIO;
 		goto release_fw;
 	}

 	if (ehdr->e_phnum == 0) {
 		dev_err(pil->desc->dev, "No loadable segments\n");
 		ret = -EIO;
 		goto release_fw;
 	}
 	if (sizeof(struct elf32_phdr) * ehdr->e_phnum +
 	    sizeof(struct elf32_hdr) > fw->size) {
 		dev_err(pil->desc->dev, "Program headers not within mdt\n");
 		ret = -EIO;
 		goto release_fw;
 	}

 	ret = pil->desc->ops->init_image(pil->desc, fw->data, fw->size);
 	if (ret) {
 		dev_err(pil->desc->dev, "Invalid firmware metadata\n");
 		goto release_fw;
 	}

 	phdr = (const struct elf32_phdr *)(fw->data + sizeof(struct elf32_hdr));
 	for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
 		if (!segment_is_loadable(phdr))
 			continue;

 		ret = load_segment(phdr, i, pil);
 		if (ret) {
 			dev_err(pil->desc->dev, "Failed to load segment %d\n",
 					i);
 			goto release_fw;
 		}
 	}

 	ret = pil->desc->ops->auth_and_reset(pil->desc);
 	if (ret) {
 		dev_err(pil->desc->dev, "Failed to bring out of reset\n");
 		goto release_fw;
 	}
 	dev_info(pil->desc->dev, "brought out of reset\n");

 release_fw:
 	release_firmware(fw);
 out:
 	return ret;
 }

 /**
  * pil_get() - Load a peripheral into memory and take it out of reset
  * @name: pointer to a string containing the name of the peripheral to load
  *
  * This function returns a pointer if it succeeds. If an error occurs an
  * ERR_PTR is returned.
  *
  * If PIL is not enabled in the kernel, the value %NULL will be returned.
  */
 void *pil_get(const char *name)
 {
 	int ret;
 	struct pil_device *pil;
 	struct pil_device *pil_d;
 	void *retval;

 	pil = retval = find_peripheral(name);
 	if (!pil)
 		return ERR_PTR(-ENODEV);

 	pil_d = find_peripheral(pil->desc->depends_on);
 	if (pil_d) {
 		void *p = pil_get(pil_d->desc->name);
 		if (IS_ERR(p))
 			return p;
 	}

 	mutex_lock(&pil->lock);
 	if (pil->count) {
 		pil->count++;
 		goto unlock;
 	}

 	ret = load_image(pil);
 	if (ret) {
 		retval = ERR_PTR(ret);
 		goto unlock;
 	}

 	pil->count++;
 unlock:
 	mutex_unlock(&pil->lock);
 	return retval;
 }
 EXPORT_SYMBOL(pil_get);

 /**
  * pil_put() - Inform PIL the peripheral no longer needs to be active
  * @peripheral_handle: pointer from a previous call to pil_get()
  *
  * This doesn't imply that a peripheral is shutdown or in reset since another
  * driver could be using the peripheral.
  */
 void pil_put(void *peripheral_handle)
 {
 	struct pil_device *pil_d;
 	struct pil_device *pil = peripheral_handle;
 	if (!pil || IS_ERR(pil))
 		return;

 	mutex_lock(&pil->lock);
 	WARN(!pil->count, "%s: Reference count mismatch\n", __func__);
 	if (pil->count)
 		pil->count--;
 	if (pil->count == 0)
 		pil->desc->ops->shutdown(pil->desc);
 	mutex_unlock(&pil->lock);

 	pil_d = find_peripheral(pil->desc->depends_on);
 	if (pil_d)
 		pil_put(pil_d);
 }
 EXPORT_SYMBOL(pil_put);

 void pil_force_shutdown(const char *name)
 {
 	struct pil_device *pil;

 	pil = find_peripheral(name);
 	if (!pil)
 		return;

 	mutex_lock(&pil->lock);
 	if (!WARN(!pil->count, "%s: Reference count mismatch\n", __func__))
 		pil->desc->ops->shutdown(pil->desc);
 	mutex_unlock(&pil->lock);
 }
 EXPORT_SYMBOL(pil_force_shutdown);

 int pil_force_boot(const char *name)
 {
 	int ret = -EINVAL;
 	struct pil_device *pil;

 	pil = find_peripheral(name);
 	if (!pil)
 		return -EINVAL;

 	mutex_lock(&pil->lock);
 	if (!WARN(!pil->count, "%s: Reference count mismatch\n", __func__))
 		ret = load_image(pil);
 	mutex_unlock(&pil->lock);

 	return ret;
 }
 EXPORT_SYMBOL(pil_force_boot);

 #ifdef CONFIG_DEBUG_FS
 int msm_pil_debugfs_open(struct inode *inode, struct file *filp)
 {
 	filp->private_data = inode->i_private;
 	return 0;
 }

 static ssize_t msm_pil_debugfs_read(struct file *filp, char __user *ubuf,
 		size_t cnt, loff_t *ppos)
 {
 	int r;
 	char buf[40];
 	struct pil_device *pil = filp->private_data;

 	mutex_lock(&pil->lock);
 	r = snprintf(buf, sizeof(buf), "%d\n", pil->count);
 	mutex_unlock(&pil->lock);
 	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
 }

 static ssize_t msm_pil_debugfs_write(struct file *filp,
 		const char __user *ubuf, size_t cnt, loff_t *ppos)
 {
 	struct pil_device *pil = filp->private_data;
 	char buf[4];

 	if (cnt > sizeof(buf))
 		return -EINVAL;

 	if (copy_from_user(&buf, ubuf, cnt))
 		return -EFAULT;

 	if (!strncmp(buf, "get", 3)) {
 		if (IS_ERR(pil_get(pil->desc->name)))
 			return -EIO;
 	} else if (!strncmp(buf, "put", 3))
 		pil_put(pil);
 	else
 		return -EINVAL;

 	return cnt;
 }

 static const struct file_operations msm_pil_debugfs_fops = {
 	.open	= msm_pil_debugfs_open,
 	.read	= msm_pil_debugfs_read,
 	.write	= msm_pil_debugfs_write,
 };

 static struct dentry *pil_base_dir;

 static int msm_pil_debugfs_init(void)
 {
 	pil_base_dir = debugfs_create_dir("pil", NULL);
 	if (!pil_base_dir) {
 		pil_base_dir = NULL;
 		return -ENOMEM;
 	}

 	return 0;
 }
 arch_initcall(msm_pil_debugfs_init);

 static int msm_pil_debugfs_add(struct pil_device *pil)
 {
 	if (!pil_base_dir)
 		return -ENOMEM;

 	if (!debugfs_create_file(pil->desc->name, S_IRUGO | S_IWUSR,
 				pil_base_dir, pil, &msm_pil_debugfs_fops))
 		return -ENOMEM;
 	return 0;
 }
 #else
 static int msm_pil_debugfs_add(struct pil_device *pil) { return 0; }
 #endif

 static int msm_pil_shutdown_at_boot(void)
 {
 	struct pil_device *pil;

 	mutex_lock(&pil_list_lock);
 	list_for_each_entry(pil, &pil_list, list)
 		pil->desc->ops->shutdown(pil->desc);
 	mutex_unlock(&pil_list_lock);

 	return 0;
 }
 late_initcall(msm_pil_shutdown_at_boot);

 int msm_pil_register(struct pil_desc *desc)
 {
 	struct pil_device *pil = kzalloc(sizeof(*pil), GFP_KERNEL);
 	if (!pil)
 		return -ENOMEM;

 	mutex_init(&pil->lock);
 	INIT_LIST_HEAD(&pil->list);
 	pil->desc = desc;

 	mutex_lock(&pil_list_lock);
 	list_add(&pil->list, &pil_list);
 	mutex_unlock(&pil_list_lock);

 	return msm_pil_debugfs_add(pil);
 }
 EXPORT_SYMBOL(msm_pil_register);

 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("Load peripheral images and bring peripherals out of reset");
	/* Copyright (c) 2010-2012, Code Aurora Forum. All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 and
	* only version 2 as published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*/

	#include <linux/module.h>
	#include <linux/string.h>
	#include <linux/device.h>
	#include <linux/firmware.h>
	#include <linux/io.h>
	#include <linux/debugfs.h>
	#include <linux/elf.h>
	#include <linux/mutex.h>
	#include <linux/memblock.h>
	#include <linux/slab.h>

	#include <asm/uaccess.h>
	#include <asm/setup.h>

	#include "peripheral-loader.h"

	struct pil_device {
	struct pil_desc *desc;
	int count;
	struct mutex lock;
	struct list_head list;
	};

	static DEFINE_MUTEX(pil_list_lock);
	static LIST_HEAD(pil_list);

	static struct pil_device __find_peripheral(const char str)
	{
	struct pil_device *dev;

	list_for_each_entry(dev, &pil_list, list)
	if (!strcmp(dev->desc->name, str))
	return dev;
	return NULL;
	}

	static struct pil_device find_peripheral(const char str)
	{
	struct pil_device *dev;

	if (!str)
	return NULL;

	mutex_lock(&pil_list_lock);
	dev = __find_peripheral(str);
	mutex_unlock(&pil_list_lock);

	return dev;
	}

	#define IOMAP_SIZE SZ_4M

	static int load_segment(const struct elf32_phdr *phdr, unsigned num,
	struct pil_device *pil)
	{
	int ret, count, paddr;
	char fw_name[30];
	const struct firmware *fw = NULL;
	const u8 *data;

	if (memblock_is_region_memory(phdr->p_paddr, phdr->p_memsz)) {
	dev_err(pil->desc->dev, "Kernel memory would be overwritten");
	return -EPERM;
	}

	if (phdr->p_filesz) {
	snprintf(fw_name, ARRAY_SIZE(fw_name), "%s.b%02d",
	pil->desc->name, num);
	ret = request_firmware(&fw, fw_name, pil->desc->dev);
	if (ret) {
	dev_err(pil->desc->dev, "Failed to locate blob %s\n",
	fw_name);
	return ret;
	}

	if (fw->size != phdr->p_filesz) {
	dev_err(pil->desc->dev,
	"Blob size %u doesn't match %u\n", fw->size,
	phdr->p_filesz);
	ret = -EPERM;
	goto release_fw;
	}
	}

	/* Load the segment into memory */
	count = phdr->p_filesz;
	paddr = phdr->p_paddr;
	data = fw ? fw->data : NULL;
	while (count > 0) {
	int size;
	u8 __iomem *buf;

	size = min_t(size_t, IOMAP_SIZE, count);
	buf = ioremap(paddr, size);
	if (!buf) {
	dev_err(pil->desc->dev, "Failed to map memory\n");
	ret = -ENOMEM;
	goto release_fw;
	}
	memcpy(buf, data, size);
	iounmap(buf);

	count -= size;
	paddr += size;
	data += size;
	}

	/* Zero out trailing memory */
	count = phdr->p_memsz - phdr->p_filesz;
	while (count > 0) {
	int size;
	u8 __iomem *buf;

	size = min_t(size_t, IOMAP_SIZE, count);
	buf = ioremap(paddr, size);
	if (!buf) {
	dev_err(pil->desc->dev, "Failed to map memory\n");
	ret = -ENOMEM;
	goto release_fw;
	}
	memset(buf, 0, size);
	iounmap(buf);

	count -= size;
	paddr += size;
	}

	ret = pil->desc->ops->verify_blob(pil->desc, phdr->p_paddr,
	phdr->p_memsz);
	if (ret)
	dev_err(pil->desc->dev, "Blob %u failed verification\n", num);

	release_fw:
	release_firmware(fw);
	return ret;
	}

	#define segment_is_hash(flag) (((flag) & (0x7 << 24)) == (0x2 << 24))

	static int segment_is_loadable(const struct elf32_phdr *p)
	{
	return (p->p_type & PT_LOAD) && !segment_is_hash(p->p_flags);
	}

	static int load_image(struct pil_device *pil)
	{
	int i, ret;
	char fw_name[30];
	struct elf32_hdr *ehdr;
	const struct elf32_phdr *phdr;
	const struct firmware *fw;

	snprintf(fw_name, sizeof(fw_name), "%s.mdt", pil->desc->name);
	ret = request_firmware(&fw, fw_name, pil->desc->dev);
	if (ret) {
	dev_err(pil->desc->dev, "Failed to locate %s\n", fw_name);
	goto out;
	}

	if (fw->size < sizeof(*ehdr)) {
	dev_err(pil->desc->dev, "Not big enough to be an elf header\n");
	ret = -EIO;
	goto release_fw;
	}

	ehdr = (struct elf32_hdr *)fw->data;
	if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG)) {
	dev_err(pil->desc->dev, "Not an elf header\n");
	ret = -EIO;
	goto release_fw;
	}

	if (ehdr->e_phnum == 0) {
	dev_err(pil->desc->dev, "No loadable segments\n");
	ret = -EIO;
	goto release_fw;
	}
	if (sizeof(struct elf32_phdr) * ehdr->e_phnum +
	sizeof(struct elf32_hdr) > fw->size) {
	dev_err(pil->desc->dev, "Program headers not within mdt\n");
	ret = -EIO;
	goto release_fw;
	}

	ret = pil->desc->ops->init_image(pil->desc, fw->data, fw->size);
	if (ret) {
	dev_err(pil->desc->dev, "Invalid firmware metadata\n");
	goto release_fw;
	}

	phdr = (const struct elf32_phdr *)(fw->data + sizeof(struct elf32_hdr));
	for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
	if (!segment_is_loadable(phdr))
	continue;

	ret = load_segment(phdr, i, pil);
	if (ret) {
	dev_err(pil->desc->dev, "Failed to load segment %d\n",
	i);
	goto release_fw;
	}
	}

	ret = pil->desc->ops->auth_and_reset(pil->desc);
	if (ret) {
	dev_err(pil->desc->dev, "Failed to bring out of reset\n");
	goto release_fw;
	}
	dev_info(pil->desc->dev, "brought out of reset\n");

	release_fw:
	release_firmware(fw);
	out:
	return ret;
	}

	/**
	* pil_get() - Load a peripheral into memory and take it out of reset
	* @name: pointer to a string containing the name of the peripheral to load
	*
	* This function returns a pointer if it succeeds. If an error occurs an
	* ERR_PTR is returned.
	*
	* If PIL is not enabled in the kernel, the value %NULL will be returned.
	*/
	void pil_get(const char name)
	{
	int ret;
	struct pil_device *pil;
	struct pil_device *pil_d;
	void *retval;

	pil = retval = find_peripheral(name);
	if (!pil)
	return ERR_PTR(-ENODEV);

	pil_d = find_peripheral(pil->desc->depends_on);
	if (pil_d) {
	void *p = pil_get(pil_d->desc->name);
	if (IS_ERR(p))
	return p;
	}

	mutex_lock(&pil->lock);
	if (pil->count) {
	pil->count++;
	goto unlock;
	}

	ret = load_image(pil);
	if (ret) {
	retval = ERR_PTR(ret);
	goto unlock;
	}

	pil->count++;
	unlock:
	mutex_unlock(&pil->lock);
	return retval;
	}
	EXPORT_SYMBOL(pil_get);

	/**
	* pil_put() - Inform PIL the peripheral no longer needs to be active
	* @peripheral_handle: pointer from a previous call to pil_get()
	*
	* This doesn't imply that a peripheral is shutdown or in reset since another
	* driver could be using the peripheral.
	*/
	void pil_put(void *peripheral_handle)
	{
	struct pil_device *pil_d;
	struct pil_device *pil = peripheral_handle;
	if (!pil \|\| IS_ERR(pil))
	return;

	mutex_lock(&pil->lock);
	WARN(!pil->count, "%s: Reference count mismatch\n", __func__);
	if (pil->count)
	pil->count--;
	if (pil->count == 0)
	pil->desc->ops->shutdown(pil->desc);
	mutex_unlock(&pil->lock);

	pil_d = find_peripheral(pil->desc->depends_on);
	if (pil_d)
	pil_put(pil_d);
	}
	EXPORT_SYMBOL(pil_put);

	void pil_force_shutdown(const char *name)
	{
	struct pil_device *pil;

	pil = find_peripheral(name);
	if (!pil)
	return;

	mutex_lock(&pil->lock);
	if (!WARN(!pil->count, "%s: Reference count mismatch\n", __func__))
	pil->desc->ops->shutdown(pil->desc);
	mutex_unlock(&pil->lock);
	}
	EXPORT_SYMBOL(pil_force_shutdown);

	int pil_force_boot(const char *name)
	{
	int ret = -EINVAL;
	struct pil_device *pil;

	pil = find_peripheral(name);
	if (!pil)
	return -EINVAL;

	mutex_lock(&pil->lock);
	if (!WARN(!pil->count, "%s: Reference count mismatch\n", __func__))
	ret = load_image(pil);
	mutex_unlock(&pil->lock);

	return ret;
	}
	EXPORT_SYMBOL(pil_force_boot);

	#ifdef CONFIG_DEBUG_FS
	int msm_pil_debugfs_open(struct inode inode, struct file filp)
	{
	filp->private_data = inode->i_private;
	return 0;
	}

	static ssize_t msm_pil_debugfs_read(struct file filp, char __user ubuf,
	size_t cnt, loff_t *ppos)
	{
	int r;
	char buf[40];
	struct pil_device *pil = filp->private_data;

	mutex_lock(&pil->lock);
	r = snprintf(buf, sizeof(buf), "%d\n", pil->count);
	mutex_unlock(&pil->lock);
	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
	}

	static ssize_t msm_pil_debugfs_write(struct file *filp,
	const char __user ubuf, size_t cnt, loff_t ppos)
	{
	struct pil_device *pil = filp->private_data;
	char buf[4];

	if (cnt > sizeof(buf))
	return -EINVAL;

	if (copy_from_user(&buf, ubuf, cnt))
	return -EFAULT;

	if (!strncmp(buf, "get", 3)) {
	if (IS_ERR(pil_get(pil->desc->name)))
	return -EIO;
	} else if (!strncmp(buf, "put", 3))
	pil_put(pil);
	else
	return -EINVAL;

	return cnt;
	}

	static const struct file_operations msm_pil_debugfs_fops = {
	.open = msm_pil_debugfs_open,
	.read = msm_pil_debugfs_read,
	.write = msm_pil_debugfs_write,
	};

	static struct dentry *pil_base_dir;

	static int msm_pil_debugfs_init(void)
	{
	pil_base_dir = debugfs_create_dir("pil", NULL);
	if (!pil_base_dir) {
	pil_base_dir = NULL;
	return -ENOMEM;
	}

	return 0;
	}
	arch_initcall(msm_pil_debugfs_init);

	static int msm_pil_debugfs_add(struct pil_device *pil)
	{
	if (!pil_base_dir)
	return -ENOMEM;

	if (!debugfs_create_file(pil->desc->name, S_IRUGO \| S_IWUSR,
	pil_base_dir, pil, &msm_pil_debugfs_fops))
	return -ENOMEM;
	return 0;
	}
	#else
	static int msm_pil_debugfs_add(struct pil_device *pil) { return 0; }
	#endif

	static int msm_pil_shutdown_at_boot(void)
	{
	struct pil_device *pil;

	mutex_lock(&pil_list_lock);
	list_for_each_entry(pil, &pil_list, list)
	pil->desc->ops->shutdown(pil->desc);
	mutex_unlock(&pil_list_lock);

	return 0;
	}
	late_initcall(msm_pil_shutdown_at_boot);

	int msm_pil_register(struct pil_desc *desc)
	{
	struct pil_device pil = kzalloc(sizeof(pil), GFP_KERNEL);
	if (!pil)
	return -ENOMEM;

	mutex_init(&pil->lock);
	INIT_LIST_HEAD(&pil->list);
	pil->desc = desc;

	mutex_lock(&pil_list_lock);
	list_add(&pil->list, &pil_list);
	mutex_unlock(&pil_list_lock);

	return msm_pil_debugfs_add(pil);
	}
	EXPORT_SYMBOL(msm_pil_register);

	MODULE_LICENSE("GPL v2");
	MODULE_DESCRIPTION("Load peripheral images and bring peripherals out of reset");