Another way - hook up JTAG. Use boundary scan to toggle the pins. That will tell you the pin number. Look up the pin number and figure out the GPIO.
On Fri, May 15, 2015 at 6:38 PM, [email protected] <[email protected]> wrote: > Turn on user space GPIO support and use sysfs to toggle the pins. Put > on a scope on the chip. Start guessing. There are only about 50 GPIOs > so this shouldn't take long. > > On Fri, May 15, 2015 at 6:27 PM, <[email protected]> wrote: >> Thanks but this is described on the mentioned by me wiki page: >> http://linux-sunxi.org/GSL1680 >> >> THE PROBLEM IS - I am unnable to find out which gpio pin is responsible for >> manage IOCNTL line of GSL1680 controller. Without enabling this pin to 1 >> controller of the MSSL1680 will not raise communication via I2C and firmware >> will be NOT loaded, so datashet is useless untill will be not found the way >> to do this (again from the same mentioned above wiki page): >> >> GPIO >> >> The chip has four main pins to communicate with a CPU: >> >> SDA and SCL: these two pins conform an I2C bus, allowing to exchange data >> between the chip and the main CPU. >> IOCNTL: this pin, when active (logic 1) enables the chip, making it to >> answer to I2C commands and read the touch screen. When inactive (logic 0), >> the chip is in Low Power state. >> INT: when there is data available (a press) or in other cases (not sure, not >> have enough documentation), this pin gets active to signal this to the CPU. >> >> Chip initialization >> >> The driver shows a quite obscure initialization procedure: >> >> Enable the chip (set IOCTNL to 1) >> >> >> >> Kind regards, Serge. >> >> >> >> >> >> On Friday, May 15, 2015 at 6:37:28 PM UTC, Jon Smirl wrote: >>> >>> Here's the datasheet >>> http://www.buydisplay.com/download/ic/GSL1680.pdf >>> >>> On Fri, May 15, 2015 at 2:32 PM, <[email protected]> wrote: >>> > In addition some details from Android >>> > Under Android : Linux 3.10.20-263387 i686 I have the following: >>> > cat /sys/class/i2c-adapter/i2c-4/ >>> > 4-0040/name >>> > MSSL1680:00. >>> > >>> > or the same under other path: >>> > >>> > cat /sys/bus/i2c/devices/i2c-4/4- >>> > 0040/name >>> > MSSL1680:00. >>> > >>> > Also in Windows drivers there is fw Silead. >>> > >>> > Only base on this I am sure that I have 1680 chip! Also it is resides on >>> > 0x40! on i2c channel. >>> > >>> > Lsmod under undroid shows gslx68x_ts driver that is relative to >>> > mentioned >>> > above i2c channel. >>> > >>> > >>> > Under any of the Linux kernel - I prefer x86_64 there is the same >>> > MSSL1680:00 but on the i2c-3 channel. >>> > >>> > I2cdetect detects nothing at the same moment. My guessing that probable >>> > mentioned here http://linux-sunxi.org/GSL1680 IOCNTL pin is not set to >>> > logical 1 and this is a main my problem - I do not know how to detect to >>> > which gpio pin on z3735f is connected IOCNTL thats mean that for your >>> > driver >>> > I could not provide -gpio parameter! >>> > To make MSSL1680 communicate via I2c channel I need 1st to set IOCNTL to >>> > 1, >>> > and do not know how to do this and I do not have >>> > /sys/devices/virtual/misc/sun4i-gpio/pin/pb3. >>> > At the same moment - It looks strange but under classical linux kernels >>> > I >>> > have only 3 items inside /sys/class/gpio numbers of them also differ >>> > from >>> > kernel to kernel. >>> > >>> > >>> > ubuntu 14.10 (3.16.0-29). shows ghpiochip 126, gpiochip154,gpiochip82 - >>> > have >>> > tried all of them - your driver wrotes (by memory) - that unable to >>> > open >>> > such device. >>> > under Arch 4.0.1 kernel - set of gpios are 338,382,410. actually the >>> > same >>> > story. >>> > >>> > Numbers are different but all binded to the same - INT33F:0x. >>> > >>> > At the same moment cat /sys/kernel/debug/gpio shows about 145 values >>> > in >>> > the table. >>> > >>> > Kind regards, >>> > Serge Kolotylo >>> > >>> > >>> > >>> > >>> > On Friday, May 15, 2015 at 2:04:48 PM UTC, [email protected] wrote: >>> >> >>> >> Dear All, please assist me in porting GSL1680 touchscreen driver to >>> >> Linux >>> >> x86/86_64 kernel. >>> >> As a testing device I have tablet =Chuwi vi8 super. Specs of it >>> >> http://techtablets.com/chuwi-vi8/ (baytrail based intel z3735f). >>> >> I have successfully run on it Linux x86 and x86_64 (Arch linux, Ubuntu, >>> >> Linux mint, sysrescue cd linux distros), the main last problem is - >>> >> there is >>> >> NO touch screen driver for Silead GSL1680 which is used in this tablet. >>> >> >>> >> I have successfully porting to x86_64 userspace driver >>> >> https://github.com/rastersoft/gsl1680. BUT the problem is according >>> >> http://linux-sunxi.org/GSL1680 to communicate with chip controller of >>> >> this >>> >> touchscreen you should 1st initialize it via setting IOCNTL line to 1, >>> >> this >>> >> line is mapped to GPIO pin. >>> >> The main problem - how to determine without any documentation, having >>> >> only >>> >> device with Android 4.4 and Windows 8.1 with working touch screen which >>> >> gpio >>> >> pin serve IOCNTL. >>> >> >>> >> Please help to find out gpio pin for IOCNTL touch screen on Chuwi vi8 >>> >> (baytrail) platform or with porting kernel level drive to Linux >>> >> vanilla >>> >> kernel for x86 plaforms. >>> >> PS: I tend to run user space mentioned above driver because porting >>> >> from >>> >> sunxi linux driver into vanilla for x86 platforms is not so easy way >>> >> due a >>> >> lot of differences of included platform headers files. >>> >> Regards, >>> >> Serge Kolotylo. >>> > >>> > -- >>> > You received this message because you are subscribed to the Google >>> > Groups >>> > "linux-sunxi" group. >>> > To unsubscribe from this group and stop receiving emails from it, send >>> > an >>> > email to [email protected]. >>> > For more options, visit https://groups.google.com/d/optout. >>> >>> >>> >>> -- >>> Jon Smirl >>> [email protected] >> >> -- >> You received this message because you are subscribed to the Google Groups >> "linux-sunxi" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/d/optout. > > > > -- > Jon Smirl > [email protected] -- Jon Smirl [email protected] -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. 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