Finding when a chip was supported in the kernel

[Rob Groner]

> -----Original Message-----
> From: Bjørn Mork [mailto:bjorn at mork.no]
> Sent: Monday, February 15, 2016 10:44 AM
> To: Carlo Caione <carlo at caione.org>
> Cc: Rob Groner <rgroner at RTD.com>; kernelnewbies at kernelnewbies.org
> Subject: Re: Finding when a chip was supported in the kernel
> 
> Carlo Caione <carlo at caione.org> writes:
> 
> > On Mon, Feb 15, 2016 at 3:44 PM, Rob Groner <rgroner at rtd.com> wrote:
> >>
<snip>
> 
> git blame on the other hand, gives you this immediately:
> 
> bjorn at nemi:/usr/local/src/git/linux$ git blame
> drivers/net/ethernet/intel/e1000e/82571.c
> e78b80b1079e1 drivers/net/ethernet/intel/e1000e/82571.c (David Ertman
> 2014-02-04 01:56:06 +0000    1) /* Intel PRO/1000 Linux driver
> [..]
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   21)
> e921eb1ac411a drivers/net/ethernet/intel/e1000e/82571.c (Bruce Allan
> 2012-11-28 09:28:37 +0000   22) /* 82571EB Gigabit Ethernet Controller
> 1605927fcee41 drivers/net/e1000e/82571.c                (Bruce Allan        2008-11-
> 21 16:51:06 -0800   23)  * 82571EB Gigabit Ethernet Controller (Copper)
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   24)  * 82571EB Gigabit Ethernet Controller (Fiber)
> ad68076e07fa0 drivers/net/e1000e/82571.c                (Bruce Allan        2008-03-
> 28 09:15:03 -0700   25)  * 82571EB Dual Port Gigabit Mezzanine Adapter
> ad68076e07fa0 drivers/net/e1000e/82571.c                (Bruce Allan        2008-03-
> 28 09:15:03 -0700   26)  * 82571EB Quad Port Gigabit Mezzanine Adapter
> ad68076e07fa0 drivers/net/e1000e/82571.c                (Bruce Allan        2008-03-
> 28 09:15:03 -0700   27)  * 82571PT Gigabit PT Quad Port Server ExpressMo
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   28)  * 82572EI Gigabit Ethernet Controller (Copper)
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   29)  * 82572EI Gigabit Ethernet Controller (Fiber)
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   30)  * 82572EI Gigabit Ethernet Controller
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   31)  * 82573V Gigabit Ethernet Controller (Copper)
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   32)  * 82573E Gigabit Ethernet Controller (Copper)
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   33)  * 82573L Gigabit Ethernet Controller
> 4662e82b2cb41 drivers/net/e1000e/82571.c                (Bruce Allan        2008-08-
> 26 18:37:06 -0700   34)  * 82574L Gigabit Network Connection
> 8c81c9c315b7e drivers/net/e1000e/82571.c                (Alexander Duyck    2009-
> 03-19 01:12:27 +0000   35)  * 82583V Gigabit Network Connection
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   36)  */
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   37)
> bc7f75fa97884 drivers/net/e1000e/82571.c                (Auke Kok           2007-09-17
> 12:30:59 -0700   38) #include "e1000.h"
> 
> 
> 
> And you can verify by looking at the commit:
> 
> 
> bjorn at nemi:/usr/local/src/git/linux$ git show 4662e82b2cb41 commit
> 4662e82b2cb41c60826e50474dd86dd5c6372b0c
> Author: Bruce Allan <bruce.w.allan at intel.com>
> Date:   Tue Aug 26 18:37:06 2008 -0700
> 
>     e1000e: add support for new 82574L part
> 
>     This new part has the same feature set as previous parts with the addition
>     of MSI-X support.
> 
>     Signed-off-by: Bruce Allan <bruce.w.allan at intel.com>
>     Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher at intel.com>
>     Signed-off-by: Jeff Garzik <jgarzik at redhat.com>
> 
> [etc]
> 
> 
> 
> I'll admit that this example was extremely easy.  Most of the time you'll have
> to figure out the relevant commits by looking at code lines related to that
> chip.  But it's still easier to look at git blame than the log if the support was
> added to an existing driver.
> 

Hmm...I don't think I share the idea that it was extremely easy.  :)  But it is something I can try at least, assuming I can get at least as far as figuring out which driver file a particular chip gets its support from.  With Intel chips, that IS pretty easy.

Using the blame I see that it gives a date and a commit reference.  How do I then correlate that to the kernel version where it first showed up?  I'm assuming there's a git command for showing that.

Rob