From mboxrd@z Thu Jan 1 00:00:00 1970 From: badguy development Subject: LTC1760, ISR Questions Date: Thu, 3 Apr 2008 23:04:02 +0000 Message-ID: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============5370590827251087969==" Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: i2c-bounces-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org Errors-To: i2c-bounces-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org To: i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org List-Id: linux-i2c@vger.kernel.org --===============5370590827251087969== Content-Type: multipart/alternative; boundary="_f7da6e94-46d4-40e6-898b-e0ef8d724bf4_" --_f7da6e94-46d4-40e6-898b-e0ef8d724bf4_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello, I am developing a driver for the LTC1760 dual battery charger. I have an interrupt occur and I get notification of that. however I cannot seem to clear the interrupt from inside the ISR and thus I= am ruined. I have learned from the research and looking around I have done, that I can= not call just any code in an ISR. the code I want to call will read the AlertResponse register of my LTC1760 = chip and that will clear the interrupt. but I get angry kernel response when I do, below is a brief dump of what I = get: BUG: scheduling while atomic: swapper/0x00010002/0 bad: scheduling from the idle thread! Unable to handle kernel NULL pointer dereference at virtual address 0000000= 0 pgd =3D c0004000 [00000000] *pgd=3D00000000 Internal error: Oops: 17 [#1] Modules linked in: i2c_battery swcamera(PF) clcdc(PF) pvr(PF) gecko_devices CPU: 0 PC is at dequeue_task+0xc/0xa8 LR is at deactivate_task+0x38/0x44 pc : [] lr : [] Tainted: PF sp : c0331c6c ip : c0331c80 fp : c0331c7c r10: 00000000 r9 : 00989642 r8 : b0e7aa00 r7 : c0335f98 r6 : c0331cd8 r5 : 00000001 r4 : c0335f98 r3 : 00000080 r2 : 00000000 r1 : 00000000 r0 : c0335f98 Flags: Nzcv IRQs off FIQs on Mode SVC_32 Segment kernel Control: C5387F Table: 868E8000 DAC: 00000017 Process swapper (pid: 0, stack limit =3D 0xc0330250) All the example code I can find regarding ISR, have access to register offs= ets and can simply clear the interrupt that way. I am new to this and am having a hard time finding direction with regards t= o how to handle linux interrupts. I need to send a request command out i2c to this device to clear this inter= rupt. I am not 100% sure about this, but it is what the data sheet has led me to = believe. I would appreciate any help on this, and perhaps even a reference to what m= aterial I should look at to find this answer. Thanks ahead of time. Please CC me at badguydevelopment-PkbjNfxxIARBDgjK7y7TUQ@public.gmane.org=20 I am still trying to join the list. P.S. I accidently clicked send before filling out the Subject, so I scanned th= e maillist and did not find my message. I think perhaps it was rejected due to no subject, if it was not, and I sub= mitted two of them please accept my apologies. -Christian Hunt _________________________________________________________________ Try Chicktionary, a game that tests how many words you can form from the le= tters given. Find this and more puzzles at Live Search Games! http://g.msn.ca/ca55/207= --_f7da6e94-46d4-40e6-898b-e0ef8d724bf4_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello,

I am developing a driver for the LTC1760 dual battery charger= .

I have an interrupt occur and I get notification of that. however I cannot seem to clear the interrupt from inside the ISR and thus I= am ruined.

I have learned from the research and looking around I have done, that I can= not call just any code in an ISR.
the code I want to call will read the AlertResponse register of my LTC1760 = chip and that will clear the interrupt.

but I get angry kernel response when I do, below is a brief dump of what I = get:

BUG: scheduling while atomic: swapper/0x00010002/0
bad: sche= duling from the idle thread!
Unable to handle kernel NULL pointer derefe= rence at virtual address 00000000
pgd =3D c0004000
[00000000] *pgd=3D= 00000000
Internal error: Oops: 17 [#1]
Modules linked in: i2c_battery= swcamera(PF) clcdc(PF) pvr(PF) gecko_devices
CPU: 0
PC is at dequeue= _task+0xc/0xa8
LR is at deactivate_task+0x38/0x44
pc : [<c009b070&= gt;] lr : [<c009b218>] Tainted: P= F
sp : c0331c6c ip : c0331c80 fp : c0331c7c
r10: 00000000= r9 : 00989642 r8 : b0e7aa00
r7 : c0335f98 r6 : c0331c= d8 r5 : 00000001 r4 : c0335f98
r3 : 00000080 r2 : 0000= 0000 r1 : 00000000 r0 : c0335f98
Flags: Nzcv IRQs off&= nbsp; FIQs on Mode SVC_32 Segment kernel
Control: C5387F
= Table: 868E8000 DAC: 00000017
Process swapper (pid: 0, stack limit= =3D 0xc0330250)

All the example code I can find regarding ISR, have= access to register offsets and can simply clear the interrupt that way.I am new to this and am having a hard time finding direction with regards = to how to handle linux interrupts.

I need to send a request command = out i2c to this device to clear this interrupt.
I am not 100% sure about= this, but it is what the data sheet has led me to believe.

I would = appreciate any help on this, and perhaps even a reference to what material = I should look at to find this answer.

Thanks ahead of time.

P= lease CC me at badguydevelopment-PkbjNfxxIARBDgjK7y7TUQ@public.gmane.org
I am still trying to join = the list.

P.S.
I accidently clicked send before filling ou= t the Subject, so I scanned the maillist and did not find my message.
I = think perhaps it was rejected due to no subject, if it was not, and I submi= tted two of them please accept my apologies.

= ; -Christian Hunt

Sign in today. When you sign in to= Windows Live Messenger you could win $1000 a day until May 12th. Learn more at SignInAndWIN.ca= = --_f7da6e94-46d4-40e6-898b-e0ef8d724bf4_-- --===============5370590827251087969== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ i2c mailing list i2c-GZX6beZjE8VD60Wz+7aTrA@public.gmane.org http://lists.lm-sensors.org/mailman/listinfo/i2c --===============5370590827251087969==--