[PATCH net-next] docs: 3c509: remove note about card detection failing with overclock

[PATCH net-next] docs: 3c509: remove note about card detection failing with overclock

[Ethan Nelson-Moore]

The id_read_eeprom() function has been fixed to use a time-based
delay, so this issue can no longer occur.

Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>
---
 .../networking/device_drivers/ethernet/3com/3c509.rst       | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/Documentation/networking/device_drivers/ethernet/3com/3c509.rst b/Documentation/networking/device_drivers/ethernet/3com/3c509.rst
index 47f706bacdd9..99ec25225e56 100644
--- a/Documentation/networking/device_drivers/ethernet/3com/3c509.rst
+++ b/Documentation/networking/device_drivers/ethernet/3com/3c509.rst
@@ -177,12 +177,6 @@ While the updated driver works with most PnP BIOS programs, it does not work
 with all. This can be fixed by disabling PnP support using the 3Com-supplied
 setup program.
 
-3c509 card is not detected on overclocked machines
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-Increase the delay time in id_read_eeprom() from the current value, 500,
-to an absurdly high value, such as 5000.
-
 
 Decoding Status and Error Messages
 ----------------------------------
-- 
2.43.0

Re: [PATCH net-next] docs: 3c509: remove note about card detection failing with overclock

[Simon Horman]

On Tue, Jan 06, 2026 at 11:11:45PM -0800, Ethan Nelson-Moore wrote:
> The id_read_eeprom() function has been fixed to use a time-based
> delay, so this issue can no longer occur.

Hi Ethan,

I guess this was fixed quite some time ago, given that the driver
doesn't see much attention these days.

In any case, I think it would be worth providing a reference
to the commit where this was fixed.

> 
> Signed-off-by: Ethan Nelson-Moore <enelsonmoore@gmail.com>

...

Re: [PATCH net-next] docs: 3c509: remove note about card detection failing with overclock

[Ethan Nelson-Moore]

On Fri, Jan 9, 2026 at 10:01 AM Simon Horman <horms@kernel.org> wrote:
> In any case, I think it would be worth providing a reference
> to the commit where this was fixed.
I just checked with git blame and all of the mdelay/udelay references
in the driver predate Git history.

Re: [PATCH net-next] docs: 3c509: remove note about card detection failing with overclock

[Andrew Lunn]

On Sat, Jan 24, 2026 at 11:21:12PM -0800, Ethan Nelson-Moore wrote:
> On Fri, Jan 9, 2026 at 10:01 AM Simon Horman <horms@kernel.org> wrote:
> > In any case, I think it would be worth providing a reference
> > to the commit where this was fixed.
> I just checked with git blame and all of the mdelay/udelay references
> in the driver predate Git history.

For commits before the beginning of git, we just use the first commit
in git.

     Andrew

Re: [PATCH net-next] docs: 3c509: remove note about card detection failing with overclock

[Maciej W. Rozycki]

On Sun, 25 Jan 2026, Andrew Lunn wrote:

> > > In any case, I think it would be worth providing a reference
> > > to the commit where this was fixed.
> > I just checked with git blame and all of the mdelay/udelay references
> > in the driver predate Git history.
> 
> For commits before the beginning of git, we just use the first commit
> in git.

 As an active user of the driver I did some digging and tracked it down to 
Linux 2.1.100, where we have this (among others):

diff -u --recursive --new-file v2.1.99/linux/drivers/net/3c509.c linux/drivers/net/3c509.c
--- v2.1.99/linux/drivers/net/3c509.c	Mon Feb 23 18:12:05 1998
+++ linux/drivers/net/3c509.c	Thu May  7 14:40:41 1998
@@ -27,10 +27,22 @@
 	FIXES:
 		Alan Cox:       Removed the 'Unexpected interrupt' bug.
 		Michael Meskes:	Upgraded to Donald Becker's version 1.07.
-		Phil Blundell:  Media selection support.
+		Alan Cox:	Increased the eeprom delay. Regardless of 
+				what the docs say some people definitely
+				get problems with lower (but in card spec)
+				delays
+		v1.10 4/21/97 Fixed module code so that multiple cards may be detected,
+				other cleanups.  -djb
+		Andrea Arcangeli:	Upgraded to Donald Becker's version 1.12.
 */
[...] 
 /* Read a word from the EEPROM using the regular EEPROM access register.
    Assume that we are in register window zero.
  */
-__initfunc(static ushort read_eeprom(short ioaddr, int index))
+static ushort read_eeprom(short ioaddr, int index)
 {
 	outw(EEPROM_READ + index, ioaddr + 10);
 	/* Pause for at least 162 us. for the read to take place. */
-	udelay (300);
+	udelay (500);
 	return inw(ioaddr + 12);
 }
 
 /* Read a word from the EEPROM when in the ISA ID probe state. */
-__initfunc(static ushort id_read_eeprom(int index))
+static ushort id_read_eeprom(int index)
 {
 	int bit, word = 0;
 
@@ -340,8 +340,8 @@
 	outb(EEPROM_READ + index, id_port);
 
 	/* Pause for at least 162 us. for the read to take place. */
-	udelay (300);
-
+	udelay (500);
+	
 	for (bit = 15; bit >= 0; bit--)
 		word = (word << 1) + (inb(id_port) & 0x01);
 
-- so it's not about using a time-based vs some other kind of delay.  The 
comment to be removed was only added along with the whole document on the 
3c509 driver with Linux 2.5.13, much later (2002 vs 1998), and therefore 
still stands.

 NAK for the change then.  Where has the idea to drop this comment come 
from anyway?

  Maciej