Now I'm developing project and I want to choose Raspberry like the control module. I want to control the frequency synthesizer by SPI, but also I need SPI for TFT Touch Display. So what can I do to combine this devices?
Recent Pis (the ones with the 40 pin expansion header) and the compute module have two accessible SPI peripherals.
The main SPI has two chip selects.
The auxiliary SPI has thee chip selects.
http://abyz.me.uk/rpi/pigpio/index.html#Type_3 shows the pin outs. Main SPI MOSI/MISO/SCLK/CE?, auxiliary SPI mosi/miso/sclk, ce?.
The recent kernel driver (spi_bcm2835) can handle both devices and can also use arbitrary GPIO for chip selects. For details see the SPI overlays mentioned in /boot/overlays/README.
Personally I would leave the TFT screen on the main SPI device and connect your synthesiser to the auxiliary SPI device.
There are select pins on the Raspberry Pi hardware, the MISO, MOSI and SCK pins can share across the slave device (in your case, it's frequency synthesizer and TFT Display), however, you will need to separate the CE(Chip Enable/Chip Select) pins. The RPi itself have TWO hardware select pins, you can look into that.