From mboxrd@z Thu Jan 1 00:00:00 1970 From: simon-wM4F9T/ekXmXDw4h08c5KA@public.gmane.org Subject: Poulsbo I2C - /dev/i2c not seen when loading i2c-dev Date: Thu, 31 Mar 2011 18:07:26 -0400 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org Hi all, I'm hoping that someone here can help. I am trying to get userland acce= ss to the I2C bus(es) on an embedded system, however recent kernels (ie. 2.6.38) are not 'loading' any buses when I 'modprobe i2c-dev'. Going back to =932.6.32=94 I am able to see 1 bus, and 'i2cdetect 0' sh= ows a single device sitting at address 0x69 (which I believe to EEPROM on the wifi card... not confirmed). The board is built around the Poulsbo and therefore using the 'i2c-isch= ' driver. Reviewing the schematic I see that there are several buses, each going = to individual components: IT8516 U5/110+111 -> LTC1760 U6/18+22 [battery charger =96 0x1A/0x12] I= T8516 U5/115+116 -> W83L771 U60/8+7 [thermal sensor =96 0x18??] IT8516 U5/117+118 -> LSM303DLH U64/19+20 [accel/compass =96 0x19] POULSBO U2/G37+H38 -> PCI Express Socket I am a little dismayed by the comment in 'i2c-isch.c' which suggest it = can handle only one i2c bus at any time. -- /* Supports: Intel SCH chipsets (AF82US15W, AF82US15L, AF82UL11L) Note: we assume there can only be one device, with one SMBus interfa= ce. */ -- This seems to correlate to these comments: http://www.linuxforums.org/forum/programming-scripting/175147-smbus-int= el-sch-us15w.html Can anyone confirm whether this is actually the case, and whether it is possible to configure it to use a different controller address. One wou= ld expect this to be a module option I guess, however it doesn't seem to t= ake any. Many thanks in advance, Simon.