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] -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. 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