Commit b0bcdd3c authored by Jean Delvare's avatar Jean Delvare
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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

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: default avatarJean Delvare <>
parent 197027e6
...@@ -1793,17 +1793,17 @@ static int __init ...@@ -1793,17 +1793,17 @@ static int __init
w83781d_isa_found(unsigned short address) w83781d_isa_found(unsigned short address)
{ {
int val, save, found = 0; 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 */ /* Some boards declare base+0 to base+7 as a PNP device, some base+4
if (!request_region(address, 4, "w83781d")) { * to base+7 and some base+5 to base+6. So we better request each port
pr_debug("w83781d: Failed to request low part of region\n"); * individually for the probing phase. */
return 0; for (port = address; port < address + W83781D_EXTENT; port++) {
} if (!request_region(port, 1, "w83781d")) {
if (!request_region(address + 4, 4, "w83781d")) { pr_debug("w83781d: Failed to request port 0x%x\n",
pr_debug("w83781d: Failed to request high part of region\n"); port);
release_region(address, 4); goto release;
return 0; }
} }
...@@ -1877,8 +1877,8 @@ w83781d_isa_found(unsigned short address) ...@@ -1877,8 +1877,8 @@ w83781d_isa_found(unsigned short address)
val == 0x30 ? "W83782D" : "W83781D", (int)address); val == 0x30 ? "W83782D" : "W83781D", (int)address);
release: release:
release_region(address + 4, 4); for (port--; port >= address; port--)
release_region(address, 4); release_region(port, 1);
return found; return found;
} }
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