On Thu, Sep 27, 2012 at 07:40:14PM -0500, Bruce Parker wrote: > ok...see below Adding mailing list back in. Please don't drop it, and please don't top-post. > # ls /sys/class/i2c-adapter/i2c-0 > 0-0020 0-0025 0-004c 0-0054 i2c-dev > 0-0021 0-0026 0-0050 0-0055 name > 0-0022 0-0027 0-0051 0-0056 new_device > 0-0023 0-0028 0-0052 delete_device subsystem > 0-0024 0-0037 0-0053 device uevent > # ls /sys/class/i2c-adapter/i2c-0/0-0028 > driver modalias name spi_master subsystem uevent > # ls /sys/class/i2c-adapter/i2c-0/0-0028/spi_master/ > spi0 > # ls /sys/class/i2c-adapter/i2c-0/0-0028/spi_master/spi0 > device spi0.0 subsystem uevent > # ls /sys/class/i2c-adapter/i2c-0/0-0028/spi_master/spi0/spi0.0 > modalias subsystem uevent > # > > I guess I don't understand when the /dev/mtd* device is supposed to be created? > Given the above, you must have either a device tree based configuration or a platform initialization file. In there you would specify the parameters of the SPI EEPROM. Assuming it is a Jedec compliant eeprom, that would in turn instantiate the mtd devices. If you use device tree, I think you would specify partition sizes in it as well. Guenter > -----Original Message----- > From: Guenter Roeck [mailto:linux@xxxxxxxxxxxx] > Sent: Thu 9/27/2012 7:10 PM > To: Bruce Parker > Subject: Re: How to use SC18IS602 driver ? > > On Thu, Sep 27, 2012 at 05:56:02PM -0500, Bruce Parker wrote: > > I'm logged in as root, but doesn't look like "sudo" or "i2cdetect" are > > on my filesystem. Guess I need to get it added to ramdisk? > > > Try "ls /sys/class/i2c-adapter/i2c-0" > > Guenter > > > Bruce... > > > > -----Original Message----- > > From: Guenter Roeck [mailto:linux@xxxxxxxxxxxx] > > Sent: Thursday, September 27, 2012 5:48 PM > > To: Bruce Parker > > Subject: Re: How to use SC18IS602 driver ? > > > > On Thu, Sep 27, 2012 at 04:50:53PM -0500, Bruce Parker wrote: > > > Message at bottom of email... > > > > > > > -----Original Message----- > > > > From: Guenter Roeck [mailto:linux@xxxxxxxxxxxx] > > > > Sent: Tuesday, August 28, 2012 6:38 PM > > > > To: Bruce Parker > > > > Subject: Re: How to use SC18IS602 driver ? > > > > > > > > On Tue, Aug 28, 2012 at 06:34:03PM -0500, Bruce Parker wrote: > > > > > [snip] > > > > > > > > > > > > With these entries, I can successfully boot Linux and see that > > an > > > > > entry > > > > > > has been created at: > > > > > > /sys/class/i2c-adapter/i2c-0/0-0028/spi_master/spi0/spi0.0 > > > > > > > > > > > Do you also see it at /sys/class/spi_master/spi0/spi0.0 ? > > > > > > > > > > Yes > > > > > > > > > > > In the past I have accessed eeproms by just having them in the > > > > device > > > > > > tree, then doing open(/sys/bus/i2c/devices/0-005x/eeprom) to get > > > > file > > > > > > descriptor. Then using file descriptor to do > > > read()/write()...pretty > > > > > > straight forward. Of course those eeproms were hanging directly > > on > > > > the > > > > > > I2C bus. > > > > > > > > > > Yes, this is how it works with I2C EEPROMs, or with AT25 > > conpatible > > > > SPI > > > > > EEPROMs. > > > > > m25p80 works differently; it creates an mfd device. > > > > > > > > > > Do you see any output with dmesg ? You should either see something > > > > like > > > > > m25p80 spi0.0: s25sl064a (xxx Kbytes) > > > > > or > > > > > m25p80 spi0.0: unrecognized JEDEC id ffffff > > > > > > > > > > In the latter case, try again with mode 3 instead of mode 0. > > > > > > > > > > No, but I don't have the hardware with the bridge and m25p80 on it > > > > yet. > > > > > Does that matter? > > > > > > > > Ok, then I guess you'll have to wait for the hardware. The /dev/mtd > > > > entries will > > > > only be created if the hardware is actually there. > > > > > > > > Guenter > > > Hi again Guenter, > > > I have my hardware now, but it does not appear to be discovered by the > > > kernel at boot time. Using an I2C bus monitor, I do not see any > > accesses > > > to the I2C bridge during boot. The device is definitely in the device > > > tree because the /sys/class/spi_master/spi0/spi0.0 file is being > > > created. Should I see the kernel probing for the Bridge during boot > > > time? Is there some specific kernel configuration I need to ask my > > > kernel guy to enable? > > > > > The driver is not an auto-detect driver, so you would not see any i2c > > activity > > unless you try to access a SPI device. > > > > What do you see if you run "sudo i2cdetect 0" ? > > > > Guenter > > > > > _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
