------   my mail ------

I would to ask you some info about arcshannon.c.
In the Linux kernel tree there's a file (shannon.h, located
in /include/asm-arm/arch-sa1100) which is written by you.
I see the code has been taken from comp.os.inferno; reading that thread,
that code seem to come from arcshannon.c. Unfortunatly i've not found
any reference about that, apart from the tuxscreen website
(http://tuxscreen.net/download/howdidthisgethere/README.txt) where the
writer stated to don't known who owned this code and rise some doubts
about the distribution due its licence.

So, i'm writing You in hope to get more info to clarify the matter.
Thanks


regards, Marco



------------ the answer ---------------------

that's very odd. i wonder why they credited me. i also don't understand the
reference to the usenet group comp.os.inferno (i didn't think this sort
of code was published there, but perhaps someone did).

i wouldn't have written #defines with SHANNON_GPIO in front of them.
in Inferno they'd all have been enums with a different format.
and indeed, in os/sa1100/archshannon.c i find
        /*
         *      GPIO asignments.  Not all used in this file, but gathered here for
         *      documental purposes.
         */
        gpio_ee_cs =            0,              /* out */
        gpio_wheaties = 1,              /* out */
        /* lcd lower = GPIO 2-9 */
        gpio_spi_dout = 10,             /* out, spi data */
        gpio_spi_din =          11,             /* in, spi data */
        gpio_spi_sclk = 12,             /* out, spi clock */
        gpio_spi_unkn = 13,             /* unknown, may be spi framing */
        gpio_spi_rtsn = 14,             /* ??, spi ?? */
        gpio_spi_cts =          15,             /* ??, spi ?? */
        gpio_irq_codec =        16,             /* in, irq from ucb1200 */
        gpio_dsp_reset =        17,             /* out */
        gpio_codec_reset =      18,             /* out */
        gpio_u3_rts =           19,             /* ?? */
        gpio_u3_cts =           20,             /* ?? */
        gpio_sense12v = 21,             /* in, 12v flash unprotect detected */
        gpio_disp_en =  22,             /* out */
        gpio_23 =                       23,             /* XXX GPIO 23 unaccounted for */
        GPIOeject_0=            24,             /* in */
        GPIOeject_1=            25,             /* in */
        GPIOrdy_0=              26,             /* in */
        GPIOrdy_1=              27,             /* in */
and perhaps there are other declarations elsewhere.
perhaps i posted a summary of the GPIO assignments in comp.os.inferno? i don't remember doing so.

most of the Shannon code was written not by me but by various people in Lucent's old Inferno Business Unit
from 1997 to 1999. Shannon was the internal code name for the SA1100-based phone.
i did do the revised Shannon driver for the TAD telephony chip,
and some non-trivial work on the kernel and applications,
as part of a larger group at Vita Nuova, who also contributed.
subsequently we (Vita Nuova) acquired distribution and re-licensing rights to
Inferno, and the trademarks, and I'm a director, so I can state the following.

the correct copyright notice for the original shannon software is:

        Inferno® Copyright © 1996-1999 Lucent Technologies Inc.  All rights reserved.
        Inferno revisions Copyright © 1999 Vita Nuova Limited.  All rights reserved.
        Inferno revisions and new material Copyright © 2000-2002 Vita Nuova Holdings Limited. All rights reserved.

        Lucida® fonts Copyright © 1985 Bigelow & Holmes Inc.

        Inferno, Styx, Dis and Limbo are registered trademarks of Vita Nuova Holdings Limited in the USA and other countries.

having said all that, since all that the Linux shannon.h has used from
the code is the GPIO pin assignment, with (expanded) comments, it's
probably best instead to write:

        GPIO pin assignment taken from Inferno Third Edition's os/sa1100/archshannon.c
        [and any other relevant files]

that's just to provide the provenance (ie, where the pin assignment came from).
in this case there isn't really any copyright material used directly as such,
since the pin assignment is hardly copyright,
and i think it's fair use to use the snippets of explanatory text from
the original comments, especially since the shannon.h file has more explanation.
the original archshannon.c text is indeed copyright Lucent and others,
but people will find that if they follow up the reference.

Regards
Charles Forsyth
Vita Nuova