hwmon: (lm78) Request I/O ports individually for probing

Different motherboards have different PNP declarations for LM78/LM79 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 an LM78 or LM79 chip, the useful port range will be requested again, as a single block. This fixes the driver on the Olivetti M3000 DT 540, at least. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: stable@kernel.org

hwmon: (lm78) Request I/O ports individually for probing
Different motherboards have different PNP declarations for LM78/LM79 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 an LM78 or LM79 chip, the useful port range will be requested again, as a single block. This fixes the driver on the Olivetti M3000 DT 540, at least. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: stable@kernel.org
Jean Delvare
1 parent 85f8d3e5fa
Showing 1 changed file with 12 additions and 13 deletions Side-by-side Diff
drivers/hwmon/lm78.c
@@ -851,18 +851,17 @@
 static int __init lm78_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, "lm78")) {
-		pr_debug("lm78: Failed to request low part of region\n");
-		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 + LM78_EXTENT; port++) {
+		if (!request_region(port, 1, "lm78")) {
+			pr_debug("lm78: Failed to request port 0x%x\n", port);
+			goto release;
+		}
 	}
-	if (!request_region(address + 4, 4, "lm78")) {
-		pr_debug("lm78: Failed to request high part of region\n");
-		release_region(address, 4);
-		return 0;
-	}
  
 #define REALLY_SLOW_IO
 	/* We need the timeouts for at least some LM78-like
@@ -925,8 +924,8 @@
 			val & 0x80 ? "LM79" : "LM78", (int)address);
  
  release:
-	release_region(address + 4, 4);
-	release_region(address, 4);
+	for (port--; port >= address; port--)
+		release_region(port, 1);
 	return found;
 }
...	...	@@ -851,18 +851,17 @@
851	851	static int __init lm78_isa_found(unsigned short address)
852	852	{
853	853	int val, save, found = 0;
	854	+ int port;
854	855
855		- /* We have to request the region in two parts because some
856		- boards declare base+4 to base+7 as a PNP device */
857		- if (!request_region(address, 4, "lm78")) {
858		- pr_debug("lm78: Failed to request low part of region\n");
859		- return 0;
	856	+ /* Some boards declare base+0 to base+7 as a PNP device, some base+4
	857	+ * to base+7 and some base+5 to base+6. So we better request each port
	858	+ * individually for the probing phase. */
	859	+ for (port = address; port < address + LM78_EXTENT; port++) {
	860	+ if (!request_region(port, 1, "lm78")) {
	861	+ pr_debug("lm78: Failed to request port 0x%x\n", port);
	862	+ goto release;
	863	+ }
860	864	}
861		- if (!request_region(address + 4, 4, "lm78")) {
862		- pr_debug("lm78: Failed to request high part of region\n");
863		- release_region(address, 4);
864		- return 0;
865		- }
866	865
867	866	#define REALLY_SLOW_IO
868	867	/* We need the timeouts for at least some LM78-like
...	...	@@ -925,8 +924,8 @@
925	924	val & 0x80 ? "LM79" : "LM78", (int)address);
926	925
927	926	release:
928		- release_region(address + 4, 4);
929		- release_region(address, 4);
	927	+ for (port--; port >= address; port--)
	928	+ release_region(port, 1);
930	929	return found;
931	930	}
932	931