Are you using a level converter? The UART pins are 1.8V compatible and from the camera specifications I can see that it uses a higher voltage typically around 5V.
I can understand level converters for the mini-breakout board. But level converters for the Edison Arduino breakout board for the RX/TX pins?
The SeeedStudio camera does not work for me either on the Arduino board + Grove base shield board.
When running just the camera initialization code, dmesg spews several these warnings:
[ 1097.644374] HSU serial 0000:00:04.2: Got LSR irq(0xf9) while using DMA
[ 1097.651270] HSU serial 0000:00:04.2: Got LSR irq(0xf8) while using DMA
I think I know what I'm doing wrong. The Grove serial cam requires RS-232 and is not straight up UART TTL. The documentation on the Seeed Studio website is a bit confusing. If the camera needs RS-232, the UPM library will not work without a RS-232 transceiver.