Re: Serial Driver Name Question (kernels 2.4.x)

Ivan Passos
2002-01-08T18:44:55Z

Andrew Morton wrote:
>
> Richard, can we please get this wrapped up?
>
> My preferred approach is to change the driver naming scheme
> so that we don't have to put printf control-strings everywhere.
> We can remove a number of ifdefs that way.
>
> So for serial.c:
>
> --- linux-2.4.18-pre2/drivers/char/tty_io.c Mon Jan 7 16:48:02 2002
> +++ linux-akpm/drivers/char/tty_io.c Mon Jan 7 20:56:38 2002
> @@ -193,10 +193,13 @@ _tty_make_name(struct tty_struct *tty, c
>
> if (!tty) /* Hmm. NULL pointer. That's fun. */
> strcpy(buf, "NULL tty");
> - else
> - sprintf(buf, name,
> - idx + tty->driver.name_base);
> -
> + else {
> +#ifdef CONFIG_DEVFS_FS
> + sprintf(buf, "%s/%d", name, idx + tty->driver.name_base);
> +#else
> + sprintf(buf, "%s%d", name, idx + tty->driver.name_base);
> +#endif
> + }
> return buf;
> }
>
> --- linux-2.4.18-pre2/drivers/char/serial.c Mon Jan 7 16:48:02 2002
> +++ linux-akpm/drivers/char/serial.c Mon Jan 7 20:58:09 2002
> @@ -5387,7 +5387,7 @@ static int __init rs_init(void)
> serial_driver.driver_name = "serial";
> #endif
> #if (LINUX_VERSION_CODE > 0x2032D && defined(CONFIG_DEVFS_FS))
> - serial_driver.name = "tts/%d";
> + serial_driver.name = "tts";
> #else
> serial_driver.name = "ttyS";
> #endif

This doesn't cover all the drivers, because the definition for devfs
is that the standard serial "translates" 'ttyS' to 'tts/', and other
serial drivers "translate" 'ttyN' (where 'N' can be several
different letters -- e.g. 'C' for Cyclades, 'R' for Comtrol, 'X' for
Specialix, 'D' for Digi, etc.) to 'tts/N' (so that standard serial
and other serial devices can share the same devfs directory).

So, I believe the best way to solve this would be:

drivers/char/tty_io.c:
@@ -193,10 +193,13 @@ _tty_make_name(struct tty_struct *tty, c

if (!tty) /* Hmm. NULL pointer. That's fun. */
strcpy(buf, "NULL tty");
else
- sprintf(buf, name,
- idx + tty->driver.name_base);
+ sprintf(buf, "%s%d", name, idx + tty->driver.name_base);

return buf;
}

drivers/char/serial.c:
@@ -5387,7 +5387,7 @@ static int __init rs_init(void)
serial_driver.driver_name = "serial";
#endif
#if (LINUX_VERSION_CODE > 0x2032D && defined(CONFIG_DEVFS_FS))
- serial_driver.name = "tts/%d";
+ serial_driver.name = "tts/";
#else
serial_driver.name = "ttyS";
#endif

And then, for instance, for the Cyclades driver, we'd use:

#ifdef CONFIG_DEVFS_FS
cy_serial_driver.name = "tts/C";
#else
cy_serial_driver.name = "ttyC";
#endif

, and let's not forget the callout devices (which follow a similar
rule):

#ifdef CONFIG_DEVFS_FS
cy_callout_driver.name = "cua/C";
#else
cy_callout_driver.name = "cub";
#endif

This would apply for other drivers as well, just replacing the 'C'
by the proper letter.

So, what do you think?!?!?

Later,
--
Ivan Passos -o)
Integration Manager, Cyclades - http://www.cyclades.com /\\
Project Leader, NetLinOS - http://www.netlinos.org _\_V
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