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Commit 287d19ce authored by Stephen Hemminger's avatar Stephen Hemminger Committed by Jesse Barnes
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PCI: revise VPD access interface 



Change PCI VPD API which was only used by sysfs to something usable
in drivers.
   * move iteration over multiple words to the low level
   * use conventional types for arguments
   * add exportable wrapper

Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
parent 1120f8b8

drivers/pci/access.c

+99 −57
Original line number Diff line number Diff line
@@ -66,6 +66,39 @@ EXPORT_SYMBOL(pci_bus_write_config_byte); 
EXPORT_SYMBOL(pci_bus_write_config_word);

EXPORT_SYMBOL(pci_bus_write_config_dword);





/**

 * pci_read_vpd - Read one entry from Vital Product Data

 * @dev:	pci device struct

 * @pos:	offset in vpd space

 * @count:	number of bytes to read

 * @buf:	pointer to where to store result

 *

 */

ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf)

{

	if (!dev->vpd || !dev->vpd->ops)

		return -ENODEV;

	return dev->vpd->ops->read(dev, pos, count, buf);

}

EXPORT_SYMBOL(pci_read_vpd);



/**

 * pci_write_vpd - Write entry to Vital Product Data

 * @dev:	pci device struct

 * @pos:	offset in vpd space

 * @count:	number of bytes to read

 * @val:	value to write

 *

 */

ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void *buf)

{

	if (!dev->vpd || !dev->vpd->ops)

		return -ENODEV;

	return dev->vpd->ops->write(dev, pos, count, buf);

}

EXPORT_SYMBOL(pci_write_vpd);



/*

 * The following routines are to prevent the user from accessing PCI config

 * space when it's unsafe to do so.  Some devices require this during BIST and
@@ -176,19 +209,17 @@ static int pci_vpd_pci22_wait(struct pci_dev *dev) 
	}

}



static int pci_vpd_pci22_read(struct pci_dev *dev, int pos, int size,

			      char *buf)

static ssize_t pci_vpd_pci22_read(struct pci_dev *dev, loff_t pos, size_t count,

				  void *arg)

{

	struct pci_vpd_pci22 *vpd =

		container_of(dev->vpd, struct pci_vpd_pci22, base);

	u32 val;

	int ret = 0;

	int begin, end, i;

	int ret;

	loff_t end = pos + count;

	u8 *buf = arg;



	if (pos < 0 || pos > vpd->base.len || size > vpd->base.len  - pos)

	if (pos < 0 || pos > vpd->base.len || end > vpd->base.len)

		return -EINVAL;

	if (size == 0)

		return 0;



	if (mutex_lock_killable(&vpd->lock))

		return -EINTR;
@@ -196,73 +227,84 @@ static int pci_vpd_pci22_read(struct pci_dev *dev, int pos, int size, 
	ret = pci_vpd_pci22_wait(dev);

	if (ret < 0)

		goto out;



	while (pos < end) {

		u32 val;

		unsigned int i, skip;



		ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,

						 pos & ~3);

		if (ret < 0)

		goto out;



			break;

		vpd->busy = true;

		vpd->flag = PCI_VPD_ADDR_F;

		ret = pci_vpd_pci22_wait(dev);

		if (ret < 0)

		goto out;

	ret = pci_user_read_config_dword(dev, vpd->cap + PCI_VPD_DATA,

					 &val);

out:

	mutex_unlock(&vpd->lock);

			break;



		ret = pci_user_read_config_dword(dev, vpd->cap + PCI_VPD_DATA, &val);

		if (ret < 0)

		return ret;

			break;



	/* Convert to bytes */

	begin = pos & 3;

	end = min(4, begin + size);

	for (i = 0; i < end; ++i) {

		if (i >= begin)

		skip = pos & 3;

		for (i = 0;  i < sizeof(u32); i++) {

			if (i >= skip) {

				*buf++ = val;

				if (++pos == end)

					break;

			}

			val >>= 8;

		}

	return end - begin;

	}

out:

	mutex_unlock(&vpd->lock);

	return ret ? ret : count;

}



static int pci_vpd_pci22_write(struct pci_dev *dev, int pos, int size,

			       const char *buf)

static ssize_t pci_vpd_pci22_write(struct pci_dev *dev, loff_t pos, size_t count,

				   const void *arg)

{

	struct pci_vpd_pci22 *vpd =

		container_of(dev->vpd, struct pci_vpd_pci22, base);

	u32 val;

	const u8 *buf = arg;

	loff_t end = pos + count;

	int ret = 0;



	if (pos < 0 || pos > vpd->base.len || pos & 3 ||

	    size > vpd->base.len - pos || size < 4)

	if (pos < 0 || (pos & 3) || (count & 3) || end > vpd->base.len)

		return -EINVAL;



	val = (u8) *buf++;

	val |= ((u8) *buf++) << 8;

	val |= ((u8) *buf++) << 16;

	val |= ((u32)(u8) *buf++) << 24;



	if (mutex_lock_killable(&vpd->lock))

		return -EINTR;



	ret = pci_vpd_pci22_wait(dev);

	if (ret < 0)

		goto out;

	ret = pci_user_write_config_dword(dev, vpd->cap + PCI_VPD_DATA,

					  val);



	while (pos < end) {

		u32 val;



		val = *buf++;

		val |= *buf++ << 8;

		val |= *buf++ << 16;

		val |= *buf++ << 24;



		ret = pci_user_write_config_dword(dev, vpd->cap + PCI_VPD_DATA, val);

		if (ret < 0)

		goto out;

			break;

		ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,

						 pos | PCI_VPD_ADDR_F);

		if (ret < 0)

		goto out;

			break;



		vpd->busy = true;

		vpd->flag = 0;

		ret = pci_vpd_pci22_wait(dev);



		pos += sizeof(u32);

	}

out:

	mutex_unlock(&vpd->lock);

	if (ret < 0)

		return ret;



	return 4;

	return ret ? ret : count;

}



static void pci_vpd_pci22_release(struct pci_dev *dev)
@@ -270,7 +312,7 @@ static void pci_vpd_pci22_release(struct pci_dev *dev) 
	kfree(container_of(dev->vpd, struct pci_vpd_pci22, base));

}



static struct pci_vpd_ops pci_vpd_pci22_ops = {

static const struct pci_vpd_ops pci_vpd_pci22_ops = {

	.read = pci_vpd_pci22_read,

	.write = pci_vpd_pci22_write,

	.release = pci_vpd_pci22_release,

drivers/pci/pci-sysfs.c

+8 −30
Original line number Diff line number Diff line
@@ -371,55 +371,33 @@ pci_write_config(struct kobject *kobj, struct bin_attribute *bin_attr, 
}



static ssize_t

pci_read_vpd(struct kobject *kobj, struct bin_attribute *bin_attr,

read_vpd_attr(struct kobject *kobj, struct bin_attribute *bin_attr,

	      char *buf, loff_t off, size_t count)

{

	struct pci_dev *dev =

		to_pci_dev(container_of(kobj, struct device, kobj));

	int end;

	int ret;



	if (off > bin_attr->size)

		count = 0;

	else if (count > bin_attr->size - off)

		count = bin_attr->size - off;

	end = off + count;



	while (off < end) {

		ret = dev->vpd->ops->read(dev, off, end - off, buf);

		if (ret < 0)

			return ret;

		buf += ret;

		off += ret;

	}



	return count;

	return pci_read_vpd(dev, off, count, buf);

}



static ssize_t

pci_write_vpd(struct kobject *kobj, struct bin_attribute *bin_attr,

write_vpd_attr(struct kobject *kobj, struct bin_attribute *bin_attr,

	       char *buf, loff_t off, size_t count)

{

	struct pci_dev *dev =

		to_pci_dev(container_of(kobj, struct device, kobj));

	int end;

	int ret;



	if (off > bin_attr->size)

		count = 0;

	else if (count > bin_attr->size - off)

		count = bin_attr->size - off;

	end = off + count;



	while (off < end) {

		ret = dev->vpd->ops->write(dev, off, end - off, buf);

		if (ret < 0)

			return ret;

		buf += ret;

		off += ret;

	}



	return count;

	return pci_write_vpd(dev, off, count, buf);

}



#ifdef HAVE_PCI_LEGACY
@@ -845,8 +823,8 @@ static int pci_create_capabilities_sysfs(struct pci_dev *dev) 
		attr->size = dev->vpd->len;

		attr->attr.name = "vpd";

		attr->attr.mode = S_IRUSR | S_IWUSR;

		attr->read = pci_read_vpd;

		attr->write = pci_write_vpd;

		attr->read = read_vpd_attr;

		attr->write = write_vpd_attr;

		retval = sysfs_create_bin_file(&dev->dev.kobj, attr);

		if (retval) {

			kfree(dev->vpd->attr);

drivers/pci/pci.h

+3 −3
Original line number Diff line number Diff line
@@ -56,14 +56,14 @@ extern int pci_user_write_config_word(struct pci_dev *dev, int where, u16 val); 
extern int pci_user_write_config_dword(struct pci_dev *dev, int where, u32 val);



struct pci_vpd_ops {

	int (*read)(struct pci_dev *dev, int pos, int size, char *buf);

	int (*write)(struct pci_dev *dev, int pos, int size, const char *buf);

	ssize_t (*read)(struct pci_dev *dev, loff_t pos, size_t count, void *buf);

	ssize_t (*write)(struct pci_dev *dev, loff_t pos, size_t count, const void *buf);

	void (*release)(struct pci_dev *dev);

};



struct pci_vpd {

	unsigned int len;

	struct pci_vpd_ops *ops;

	const struct pci_vpd_ops *ops;

	struct bin_attribute *attr; /* descriptor for sysfs VPD entry */

};

include/linux/pci.h

+4 −0
Original line number Diff line number Diff line
@@ -687,6 +687,10 @@ int pci_back_from_sleep(struct pci_dev *dev); 
/* Functions for PCI Hotplug drivers to use */

int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap);



/* Vital product data routines */

ssize_t pci_read_vpd(struct pci_dev *dev, loff_t pos, size_t count, void *buf);

ssize_t pci_write_vpd(struct pci_dev *dev, loff_t pos, size_t count, const void *buf);



/* Helper functions for low-level code (drivers/pci/setup-[bus,res].c) */

void pci_bus_assign_resources(struct pci_bus *bus);

void pci_bus_size_bridges(struct pci_bus *bus);