From mboxrd@z Thu Jan 1 00:00:00 1970 From: cmcvista@gmail.com (Chriz Chow) Date: Mon, 19 Nov 2018 21:48:13 +0800 Subject: Why eeprom driver is read-only ? In-Reply-To: References: Message-ID: To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org Hello, It seems that some drivers in drivers/misc/eeprom does support write access. For example at24.c seems to have a function at24_write(). https://github.com/torvalds/linux/blob/master/drivers/misc/eeprom/at24.c However some drivers doesn?t have write support, I believe it is because of simplicity - some eeprom are used for read only, such as ddr4 spd eeprom. Point me out if I am wrong. Chriz Enviado desde mi iPhone > El 19 nov 2018, a las 9:12 p. m., Ruben Safir escribi?: > >> On 11/19/18 7:08 AM, Ranran wrote: >> Hello, >> >> What is the reason that kernel driver of eeprom is configured only as >> read-only ? >> >> Is it because the BIOS is stored there ? >> >> Is there a way to make it writable ? >> >> Thank you, >> Ran >> >> _______________________________________________ >> Kernelnewbies mailing list >> Kernelnewbies at kernelnewbies.org >> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >> > > > because the ROM is read only? > > > -- > So many immigrant groups have swept through our town > that Brooklyn, like Atlantis, reaches mythological > proportions in the mind of the world - RI Safir 1998 > http://www.mrbrklyn.com > DRM is THEFT - We are the STAKEHOLDERS - RI Safir 2002 > > http://www.nylxs.com - Leadership Development in Free Software > http://www.brooklyn-living.com > > Being so tracked is for FARM ANIMALS and and extermination camps, > but incompatible with living as a free human being. -RI Safir 2013 > > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies at kernelnewbies.org > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies -------------- next part -------------- An HTML attachment was scrubbed... URL: From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-x42d.google.com ([2607:f8b0:4864:20::42d]) by shelob.surriel.com with esmtps (TLSv1.2:ECDHE-RSA-AES128-GCM-SHA256:128) (Exim 4.91) (envelope-from ) id 1gOjvT-000343-OX for kernelnewbies@kernelnewbies.org; Mon, 19 Nov 2018 08:49:19 -0500 Received: by mail-pf1-x42d.google.com with SMTP id b85so8062002pfc.3 for ; Mon, 19 Nov 2018 05:49:19 -0800 (PST) Mime-Version: 1.0 (1.0) Subject: Re: Why eeprom driver is read-only ? From: Chriz Chow In-Reply-To: Date: Mon, 19 Nov 2018 21:48:13 +0800 Message-Id: References: To: Ruben Safir Cc: kernelnewbies@kernelnewbies.org List-Id: Learn about the Linux kernel List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============4633359956438966937==" Errors-To: kernelnewbies-bounces@kernelnewbies.org Message-ID: <20181119134813.nuDYODLdyBf446BHshWZFtNw-athyNXIUySgYua4UOE@z> --===============4633359956438966937== Content-Type: multipart/alternative; boundary=Apple-Mail-7BEEBCC5-DA4D-431C-A759-A70D6E732FB4 Content-Transfer-Encoding: 7bit --Apple-Mail-7BEEBCC5-DA4D-431C-A759-A70D6E732FB4 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Hello, It seems that some drivers in drivers/misc/eeprom does support write access.= For example at24.c seems to have a function at24_write(). https://github.com/torvalds/linux/blob/master/drivers/misc/eeprom/at24.c However some drivers doesn=E2=80=99t have write support, I believe it is bec= ause of simplicity - some eeprom are used for read only, such as ddr4 spd ee= prom. Point me out if I am wrong.=20 Chriz Enviado desde mi iPhone > El 19 nov 2018, a las 9:12 p. m., Ruben Safir escribi= =C3=B3: >=20 >> On 11/19/18 7:08 AM, Ranran wrote: >> Hello, >>=20 >> What is the reason that kernel driver of eeprom is configured only as >> read-only ? >>=20 >> Is it because the BIOS is stored there ? >>=20 >> Is there a way to make it writable ? >>=20 >> Thank you, >> Ran >>=20 >> _______________________________________________ >> Kernelnewbies mailing list >> Kernelnewbies@kernelnewbies.org >> https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies >>=20 >=20 >=20 > because the ROM is read only? >=20 >=20 > --=20 > So many immigrant groups have swept through our town > that Brooklyn, like Atlantis, reaches mythological > proportions in the mind of the world - RI Safir 1998 > http://www.mrbrklyn.com > DRM is THEFT - We are the STAKEHOLDERS - RI Safir 2002 >=20 > http://www.nylxs.com - Leadership Development in Free Software > http://www.brooklyn-living.com >=20 > Being so tracked is for FARM ANIMALS and and extermination camps, > but incompatible with living as a free human being. -RI Safir 2013 >=20 > _______________________________________________ > Kernelnewbies mailing list > Kernelnewbies@kernelnewbies.org > https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies --Apple-Mail-7BEEBCC5-DA4D-431C-A759-A70D6E732FB4 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable Hello,

It seems that som= e drivers in drivers/misc/eeprom does support write access. For example at24= .c seems to have a function at24_write().

h= ttps://github.com/torvalds/linux/blob/master/drivers/misc/eeprom/at24.c<= /div>

However some drivers doesn=E2=80=99t have write sup= port, I believe it is because of simplicity - some eeprom are used for read o= nly, such as ddr4 spd eeprom.

Point me out if I= am wrong. 

Chriz

Enviado desde mi iPhone
<= br>El 19 nov 2018, a las 9:12 p. m., Ruben Safir <ruben@mrbrklyn.com> escribi=C3=B3:

On 11/19/18 7:08 AM, Ranran wrote= :
Hello,

What is the reason that kernel driver of eeprom is configured only= as
read-only ?

Is it because the BIOS is stored there ?

Is there a way to make it writable ?

Thank you,
Ran
<= /span>
_____________________= __________________________
= Kernelnewbies mailing list
Kernelnewbies= @kernelnewbies.org
https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies



because the ROM is read only?
<= span>

--
So many immigrant= groups have swept through our town
that Brooklyn, like Atla= ntis, reaches mythological
proportions in the mind of the wo= rld - RI Safir 1998
http= ://www.mrbrklyn.com
DRM is THEFT - We are the STAKEHOLDE= RS - RI Safir 2002

http://www.nylxs.com - Leadership Development in Free Software<= /span>
http://www.brookl= yn-living.com

Being so tracked is for FA= RM ANIMALS and and extermination camps,
but incompatible wit= h living as a free human being. -RI Safir 2013

_______________________________________________
Kernelne= wbies mailing list
Kernelnewbies@kernelnewbies.org
https://lists.k= ernelnewbies.org/mailman/listinfo/kernelnewbies
= --Apple-Mail-7BEEBCC5-DA4D-431C-A759-A70D6E732FB4-- --===============4633359956438966937== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Kernelnewbies mailing list Kernelnewbies@kernelnewbies.org https://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies --===============4633359956438966937==--