Compile from source USB-to-Serial drivers on CentOS7
I ran into an issue recently migrating to Cent0S 7 as my primary workstation. In Windows my Raspberry Pis happily conversed with my workstation of puTTY using a USB-to-Serial connector from AdaFruit. This was great, allowing me to program without hooking up a monitor of HDMI for console access. However, despite all the statements of the connector seamlessly working on Linux, it did not, issuing errors like 'serial connection unable to establish'.
Suspecting a driver issue, I began looking for the chipset. According the AdaFruit, the chipset had changed a number of times for this particular connector.
AdaFruit Product Details
This lead me to SiLabs where I found the latest driver of the current chipset
SiLabs Software Downloads
From this page I was able to download the proper software for my kernel (3.x.x) after creating an account (?...what sacrifices). Anyway, once I sold my soul, I managed to get the files downloaded to start the REAL fun.
Lets do this!
Now for the exciting part...ok...more exciting than pouring over forums and websites...
# unzip the DL
[Downloads]$ unzip Linux-3-x-x-VCP-Driver-Source.zip
Archive: Linux-3-x-x-VCP-Driver-Source.zip
creating: Linux_3.x.x_VCP_Driver_Source/
inflating: Linux_3.x.x_VCP_Driver_Source/cp210x.c
creating: __MACOSX/
creating: __MACOSX/Linux_3.x.x_VCP_Driver_Source/
inflating: __MACOSX/Linux_3.x.x_VCP_Driver_Source/._cp210x.c
inflating: Linux_3.x.x_VCP_Driver_Source/cp210x_gpio_example.c
inflating: __MACOSX/Linux_3.x.x_VCP_Driver_Source/._cp210x_gpio_example.c
inflating: Linux_3.x.x_VCP_Driver_Source/CP210x_VCP_Linux_3.13.x_Release_Notes.txt
inflating: __MACOSX/Linux_3.x.x_VCP_Driver_Source/._CP210x_VCP_Linux_3.13.x_Release_Notes.txt
inflating: Linux_3.x.x_VCP_Driver_Source/Makefile
inflating: __MACOSX/Linux_3.x.x_VCP_Driver_Source/._Makefile
inflating: __MACOSX/._Linux_3.x.x_VCP_Driver_Source
# cd to the source...ignore that MAC stuff...
[Downloads]$ ls
Linux_3.x.x_VCP_Driver_Source __MACOSX
[Downloads]$ cd Linux_3.x.x_VCP_Driver_Source
[Linux_3.x.x_VCP_Driver_Source]$ ls
cp210x.c cp210x_gpio_example.c CP210x_VCP_Linux_3.13.x_Release_Notes.txt Makefile
# make stuff happen...
[Linux_3.x.x_VCP_Driver_Source]$ make
make -C /lib/modules/3.10.0-514.26.2.el7.x86_64/build M=/home/xiphos/Downloads/Linux_3.x.x_VCP_Driver_Source modules
make[1]: Entering directory `/usr/src/kernels/3.10.0-514.26.2.el7.x86_64'
CC [M] /home/workstation/Downloads/Linux_3.x.x_VCP_Driver_Source/cp210x.o
Building modules, stage 2.
MODPOST 1 modules
CC /home/workstation/Downloads/Linux_3.x.x_VCP_Driver_Source/cp210x.mod.o
LD [M] /home/workstation/Downloads/Linux_3.x.x_VCP_Driver_Source/cp210x.ko
make[1]: Leaving directory `/usr/src/kernels/3.10.0-514.26.2.el7.x86_64'
[Linux_3.x.x_VCP_Driver_Source]$ ls
cp210x.c
cp210x.ko
cp210x.mod.o
CP210x_VCP_Linux_3.13.x_Release_Notes.txt
modules.order
cp210x_gpio_example.c
cp210x.mod.c
cp210x.o
Makefile
Module.symvers
# move compiled drivers where they need to go...
[Linux_3.x.x_VCP_Driver_Source]$ sudo cp cp210x.ko /lib/modules/3.10.0-514.26.2.el7.x86_64/kernel/drivers/usb/serial
######################################################################
# This next part hung me up because the Release notes clearly state # needing to insmod a usbserial.ko module (insert into kernel). This is # hard because that module doesn't exist in CentOS7...so I just skipped # it and insmod'ed the driver :)
####################################################################
[Linux_3.x.x_VCP_Driver_Source]$ insmod /lib/modules/3.10.0-514.26.2.el7.x86_64/kernel/drivers/usb/serial/cp210x.ko
[Linux_3.x.x_VCP_Driver_Source]$ sudo chmod 666 /dev/ttyUSB0
# if you have a ttyUSB1, chmod it as well
$ sudo chmod 777 /dev/ttyUSB1 ...and with that, I was able to establish a PuTTY serial session between my CentOS7 and Raspberry Pi. Now, so can you!