hwmon: (w83781d) Request I/O ports individually for probing
Different motherboards have different PNP declarations for
W83781D/W83782D chips. Some declare the whole range of I/O ports (8
ports), some declare only the useful ports (2 ports at offset 5) and
some declare fancy ranges, for example 4 ports at offset 4. To
properly handle all cases, request all ports individually for probing.
After we have determined that we really have a W83781D or W83782D
chip, the useful port range will be requested again, as a single
block.
I did not see a board which needs this yet, but I know of one for lm78
driver and I'd like to keep the logic of these two drivers in sync.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@kernel.org
diff --git a/drivers/hwmon/w83781d.c b/drivers/hwmon/w83781d.c
index 05f9225..32d4ade 100644
--- a/drivers/hwmon/w83781d.c
+++ b/drivers/hwmon/w83781d.c
@@ -1793,17 +1793,17 @@
w83781d_isa_found(unsigned short address)
{
int val, save, found = 0;
+ int port;
- /* We have to request the region in two parts because some
- boards declare base+4 to base+7 as a PNP device */
- if (!request_region(address, 4, "w83781d")) {
- pr_debug("w83781d: Failed to request low part of region\n");
- return 0;
- }
- if (!request_region(address + 4, 4, "w83781d")) {
- pr_debug("w83781d: Failed to request high part of region\n");
- release_region(address, 4);
- return 0;
+ /* Some boards declare base+0 to base+7 as a PNP device, some base+4
+ * to base+7 and some base+5 to base+6. So we better request each port
+ * individually for the probing phase. */
+ for (port = address; port < address + W83781D_EXTENT; port++) {
+ if (!request_region(port, 1, "w83781d")) {
+ pr_debug("w83781d: Failed to request port 0x%x\n",
+ port);
+ goto release;
+ }
}
#define REALLY_SLOW_IO
@@ -1877,8 +1877,8 @@
val == 0x30 ? "W83782D" : "W83781D", (int)address);
release:
- release_region(address + 4, 4);
- release_region(address, 4);
+ for (port--; port >= address; port--)
+ release_region(port, 1);
return found;
}