[PATCH] hwmon: Drop legacy ISA address support from it87

Drop legacy ISA address support from the it87 driver. All supported
chips are Super-I/O chips, so the device ISA address can be safely read
from Super-I/O space rather than blindly assumed.

Two nearby inaccurate documentation statements have been fixed as well:
* The IT8705F doesn't have an SMBus interface.
* The SiS950 doesn't have a distinct prefix.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 15 insertions, 44 deletions

diff --git a/Documentation/hwmon/it87 b/Documentation/hwmon/it87
index 0d0195040d88..7f42e441c645 100644
--- a/Documentation/hwmon/it87
+++ b/Documentation/hwmon/it87
@@ -4,18 +4,18 @@ Kernel driver it87
 Supported chips:
   * IT8705F
     Prefix: 'it87'
-    Addresses scanned: from Super I/O config space, or default ISA 0x290 (8 I/O ports)
+    Addresses scanned: from Super I/O config space (8 I/O ports)
     Datasheet: Publicly available at the ITE website
                http://www.ite.com.tw/
   * IT8712F
     Prefix: 'it8712'
     Addresses scanned: I2C 0x28 - 0x2f
-                       from Super I/O config space, or default ISA 0x290 (8 I/O ports)
+                       from Super I/O config space (8 I/O ports)
     Datasheet: Publicly available at the ITE website
                http://www.ite.com.tw/
   * SiS950   [clone of IT8705F]
-    Prefix: 'sis950'
-    Addresses scanned: from Super I/O config space, or default ISA 0x290 (8 I/O ports)
+    Prefix: 'it87'
+    Addresses scanned: from Super I/O config space (8 I/O ports)
     Datasheet: No longer be available
 
 Author: Christophe Gauthron <chrisg@0-in.com>
diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c
index 53cc2b6d6385..55e1c835a046 100644
--- a/drivers/hwmon/it87.c
+++ b/drivers/hwmon/it87.c
@@ -2,7 +2,7 @@
     it87.c - Part of lm_sensors, Linux kernel modules for hardware
              monitoring.
 
-    Supports: IT8705F  Super I/O chip w/LPC interface & SMBus
+    Supports: IT8705F  Super I/O chip w/LPC interface
               IT8712F  Super I/O chip w/LPC interface & SMBus
               Sis950   A clone of the IT8705F
 
@@ -47,7 +47,7 @@
 /* Addresses to scan */
 static unsigned short normal_i2c[] = { 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
                                         0x2e, 0x2f, I2C_CLIENT_END };
-static unsigned short isa_address = 0x290;
+static unsigned short isa_address;
 
 /* Insmod parameters */
 I2C_CLIENT_INSMOD_2(it87, it8712);
@@ -706,7 +706,7 @@ static int it87_isa_attach_adapter(struct i2c_adapter *adapter)
 }
 
 /* SuperIO detection - will change isa_address if a chip is found */
-static int __init it87_find(int *address)
+static int __init it87_find(unsigned short *address)
 {
         int err = -ENODEV;
 
@@ -757,34 +757,7 @@ int it87_detect(struct i2c_adapter *adapter, int address, int kind)
                 if (!request_region(address, IT87_EXTENT, it87_isa_driver.name))
                         goto ERROR0;
 
-        /* Probe whether there is anything available on this address. Already
-           done for SMBus and Super-I/O clients */
-        if (kind < 0) {
-                if (is_isa && !chip_type) {
-#define REALLY_SLOW_IO
-                        /* We need the timeouts for at least some IT87-like chips. But only
-                           if we read 'undefined' registers. */
-                        i = inb_p(address + 1);
-                        if (inb_p(address + 2) != i
-                         || inb_p(address + 3) != i
-                         || inb_p(address + 7) != i) {
-                                err = -ENODEV;
-                                goto ERROR1;
-                        }
-#undef REALLY_SLOW_IO
-
-                        /* Let's just hope nothing breaks here */
-                        i = inb_p(address + 5) & 0x7f;
-                        outb_p(~i & 0x7f, address + 5);
-                        if ((inb_p(address + 5) & 0x7f) != (~i & 0x7f)) {
-                                outb_p(i, address + 5);
-                                err = -ENODEV;
-                                goto ERROR1;
-                        }
-                }
-        }
-
-        /* OK. For now, we presume we have a valid client. We now create the
+        /* For now, we presume we have a valid client. We create the
            client structure, even though we cannot fill it completely yet.
            But it allows us to access it87_{read,write}_value. */
 
@@ -1182,20 +1155,18 @@ static struct it87_data *it87_update_device(struct device *dev)
 
 static int __init sm_it87_init(void)
 {
-        int addr, res;
-
-        if (!it87_find(&addr)) {
-                isa_address = addr;
-        }
+        int res;
 
         res = i2c_add_driver(&it87_driver);
         if (res)
                 return res;
 
-        res = i2c_isa_add_driver(&it87_isa_driver);
-        if (res) {
-                i2c_del_driver(&it87_driver);
-                return res;
+        if (!it87_find(&isa_address)) {
+                res = i2c_isa_add_driver(&it87_isa_driver);
+                if (res) {
+                        i2c_del_driver(&it87_driver);
+                        return res;
+                }
         }
 
         return 0;