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: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 98ddba9..86ec4ad 100644 (file)
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -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;
-       ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
-                                        pos & ~3);
-       if (ret < 0)
-               goto out;
 
-       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);
+       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)
+                       break;
+               vpd->busy = true;
+               vpd->flag = PCI_VPD_ADDR_F;
+               ret = pci_vpd_pci22_wait(dev);
+               if (ret < 0)
+                       break;
+
+               ret = pci_user_read_config_dword(dev, vpd->cap + PCI_VPD_DATA, &val);
+               if (ret < 0)
+                       break;
+
+               skip = pos & 3;
+               for (i = 0;  i < sizeof(u32); i++) {
+                       if (i >= skip) {
+                               *buf++ = val;
+                               if (++pos == end)
+                                       break;
+                       }
+                       val >>= 8;
+               }
+       }
 out:
        mutex_unlock(&vpd->lock);
-       if (ret < 0)
-               return ret;
-
-       /* Convert to bytes */
-       begin = pos & 3;
-       end = min(4, begin + size);
-       for (i = 0; i < end; ++i) {
-               if (i >= begin)
-                       *buf++ = val;
-               val >>= 8;
-       }
-       return end - begin;
+       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);
-       if (ret < 0)
-               goto out;
-       ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
-                                        pos | PCI_VPD_ADDR_F);
-       if (ret < 0)
-               goto out;
-       vpd->busy = true;
-       vpd->flag = 0;
-       ret = pci_vpd_pci22_wait(dev);
+
+       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)
+                       break;
+               ret = pci_user_write_config_word(dev, vpd->cap + PCI_VPD_ADDR,
+                                                pos | PCI_VPD_ADDR_F);
+               if (ret < 0)
+                       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,

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index ea54ced..c23619f 100644 (file)
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -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,
-            char *buf, loff_t off, size_t count)
+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,
-             char *buf, loff_t off, size_t count)
+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);

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 65deed8..211fd41 100644 (file)
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -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 */
 };
 

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 170f9ae..76079e1 100644 (file)
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -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);