powerpc/scom: Improve debugfs interface

[firefly-linux-kernel-4.4.55.git] / arch / powerpc / sysdev / scom.c

diff --git a/arch/powerpc/sysdev/scom.c b/arch/powerpc/sysdev/scom.c
index 3963d995648a551e0dbe355833ff3b204d6980e7..6f5a8d177c427f038aa65d0a7af9ce5657459625 100644 (file)
--- a/arch/powerpc/sysdev/scom.c
+++ b/arch/powerpc/sysdev/scom.c
@@ -25,6 +25,7 @@
 #include <asm/debug.h>
 #include <asm/prom.h>
 #include <asm/scom.h>
+#include <asm/uaccess.h>
 
 const struct scom_controller *scom_controller;
 EXPORT_SYMBOL_GPL(scom_controller);
@@ -98,61 +99,89 @@ EXPORT_SYMBOL_GPL(scom_map_device);
 #ifdef CONFIG_SCOM_DEBUGFS
 struct scom_debug_entry {
        struct device_node *dn;
-       unsigned long addr;
-       scom_map_t map;
-       spinlock_t lock;
-       char name[8];
-       struct debugfs_blob_wrapper blob;
+       struct debugfs_blob_wrapper path;
+       char name[16];
 };
 
-static int scom_addr_set(void *data, u64 val)
-{
-       struct scom_debug_entry *ent = data;
-
-       ent->addr = 0;
-       scom_unmap(ent->map);
-
-       ent->map = scom_map(ent->dn, val, 1);
-       if (scom_map_ok(ent->map))
-               ent->addr = val;
-       else
-               return -EFAULT;
-
-       return 0;
-}
-
-static int scom_addr_get(void *data, u64 *val)
+static ssize_t scom_debug_read(struct file *filp, char __user *ubuf,
+                              size_t count, loff_t *ppos)
 {
-       struct scom_debug_entry *ent = data;
-       *val = ent->addr;
-       return 0;
+       struct scom_debug_entry *ent = filp->private_data;
+       u64 __user *ubuf64 = (u64 __user *)ubuf;
+       loff_t off = *ppos;
+       ssize_t done = 0; 
+       u64 reg, reg_cnt, val;
+       scom_map_t map;
+       int rc;
+
+       if (off < 0 || (off & 7) || (count & 7))
+               return -EINVAL;
+       reg = off >> 3;
+       reg_cnt = count >> 3;
+
+       map = scom_map(ent->dn, reg, reg_cnt);
+       if (!scom_map_ok(map))
+               return -ENXIO;
+
+       for (reg = 0; reg < reg_cnt; reg++) {
+               rc = scom_read(map, reg, &val);
+               if (!rc)
+                       rc = put_user(val, ubuf64);
+               if (rc) {
+                       if (!done)
+                               done = rc;
+                       break;
+               }
+               ubuf64++;
+               *ppos += 8;
+               done += 8;
+       }
+       scom_unmap(map);
+       return done;
 }
-DEFINE_SIMPLE_ATTRIBUTE(scom_addr_fops, scom_addr_get, scom_addr_set,
-                       "0x%llx\n");
 
-static int scom_val_set(void *data, u64 val)
+static ssize_t scom_debug_write(struct file* filp, const char __user *ubuf,
+                               size_t count, loff_t *ppos)
 {
-       struct scom_debug_entry *ent = data;
-
-       if (!scom_map_ok(ent->map))
-               return -EFAULT;
-
-       scom_write(ent->map, 0, val);
-
-       return 0;
+       struct scom_debug_entry *ent = filp->private_data;
+       u64 __user *ubuf64 = (u64 __user *)ubuf;
+       loff_t off = *ppos;
+       ssize_t done = 0; 
+       u64 reg, reg_cnt, val;
+       scom_map_t map;
+       int rc;
+
+       if (off < 0 || (off & 7) || (count & 7))
+               return -EINVAL;
+       reg = off >> 3;
+       reg_cnt = count >> 3;
+
+       map = scom_map(ent->dn, reg, reg_cnt);
+       if (!scom_map_ok(map))
+               return -ENXIO;
+
+       for (reg = 0; reg < reg_cnt; reg++) {
+               rc = get_user(val, ubuf64);
+               if (!rc)
+                       rc = scom_write(map, reg,  val);
+               if (rc) {
+                       if (!done)
+                               done = rc;
+                       break;
+               }
+               ubuf64++;
+               done += 8;
+       }
+       scom_unmap(map);
+       return done;
 }
 
-static int scom_val_get(void *data, u64 *val)
-{
-       struct scom_debug_entry *ent = data;
-
-       if (!scom_map_ok(ent->map))
-               return -EFAULT;
-
-       return scom_read(ent->map, 0, val);
-}
-DEFINE_SIMPLE_ATTRIBUTE(scom_val_fops, scom_val_get, scom_val_set,
-                       "0x%llx\n");
+static const struct file_operations scom_debug_fops = {
+       .read =         scom_debug_read,
+       .write =        scom_debug_write,
+       .open =         simple_open,
+       .llseek =       default_llseek,
+};
 
 static int scom_debug_init_one(struct dentry *root, struct device_node *dn,
                               int i)
@@ -165,11 +194,9 @@ static int scom_debug_init_one(struct dentry *root, struct device_node *dn,
                return -ENOMEM;
 
        ent->dn = of_node_get(dn);
-       ent->map = SCOM_MAP_INVALID;
-       spin_lock_init(&ent->lock);
-       snprintf(ent->name, 8, "scom%d", i);
-       ent->blob.data = (void*) dn->full_name;
-       ent->blob.size = strlen(dn->full_name);
+       snprintf(ent->name, 16, "%08x", i);
+       ent->path.data = (void*) dn->full_name;
+       ent->path.size = strlen(dn->full_name);
 
        dir = debugfs_create_dir(ent->name, root);
        if (!dir) {
@@ -178,9 +205,8 @@ static int scom_debug_init_one(struct dentry *root, struct device_node *dn,
                return -1;
        }
 
-       debugfs_create_file("addr", 0600, dir, ent, &scom_addr_fops);
-       debugfs_create_file("value", 0600, dir, ent, &scom_val_fops);
-       debugfs_create_blob("devspec", 0400, dir, &ent->blob);
+       debugfs_create_blob("devspec", 0400, dir, &ent->path);
+       debugfs_create_file("access", 0600, dir, ent, &scom_debug_fops);
 
        return 0;
 }