From 69271da461ec4baf226e17d9da8f5a9837695b66 Mon Sep 17 00:00:00 2001
From: Joerg Wunsch <joerg@FreeBSD.org>
Date: Sun, 16 May 2004 21:19:59 +0000
Subject: [PATCH] Another candidate that didn't use copyin/copyout for
 user<->kernel transfers.

MFC after:	1 month
---
 sys/dev/iicbus/iic.c | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/sys/dev/iicbus/iic.c b/sys/dev/iicbus/iic.c
index 7f4221a60dd5..37c2b6186d0c 100644
--- a/sys/dev/iicbus/iic.c
+++ b/sys/dev/iicbus/iic.c
@@ -29,6 +29,7 @@
 #include <sys/param.h>
 #include <sys/kernel.h>
 #include <sys/systm.h>
+#include <sys/malloc.h>
 #include <sys/module.h>
 #include <sys/bus.h>
 #include <sys/conf.h>
@@ -246,6 +247,7 @@ iicioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
 	device_t parent = device_get_parent(iicdev);
 	struct iiccmd *s = (struct iiccmd *)data;
 	int error, count;
+	char *buf = NULL;
 
 	if (!sc)
 		return (EINVAL);
@@ -278,19 +280,37 @@ iicioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct thread *td)
 		break;
 
 	case I2CWRITE:
-		error = iicbus_write(parent, s->buf, s->count, &count, 10);
+		if (s->count <= 0) {
+			error = EINVAL;
+			break;
+		}
+		buf = malloc((unsigned long)s->count, M_TEMP, M_WAITOK);
+		error = copyin(s->buf, buf, s->count);
+		if (error)
+			break;
+		error = iicbus_write(parent, buf, s->count, &count, 10);
 		break;
 
 	case I2CREAD:
-		error = iicbus_read(parent, s->buf, s->count, &count, s->last, 10);
+		if (s->count <= 0) {
+			error = EINVAL;
+			break;
+		}
+		buf = malloc((unsigned long)s->count, M_TEMP, M_WAITOK);
+		error = iicbus_read(parent, buf, s->count, &count, s->last, 10);
+		if (error)
+			break;
+		error = copyout(buf, s->buf, s->count);
 		break;
 
 	default:
-		error = ENODEV;
+		error = ENOTTY;
 	}
 
 	iicbus_release_bus(device_get_parent(iicdev), iicdev);
 
+	if (buf != NULL)
+		free(buf, M_TEMP);
 	return (error);
 }