Does DMA serve both SRC channels

I am working on the APU driver code for DA14681/SDK1.0.8 since SDK1.0.8 doesn't have the related code ready yet.
My target is to route both PMC/I2S channels:PCM1_IN1[31-8], PCM1_IN2[31-8] to both SRC channels SRC_IN1,
SRC_IN2, and then through SRC hardware output to both SRC output channels:SRC_OUT1_REG[]/SRC_OUT2_REG[],
and then route both SRC output channels:SRC_OUT1_REG[]/SRC_OUT2_REG[] to DMA channels.
我通过DA14681数据表Rev.2.1（2016年7月15日）阅读，并在这里有疑问：
1）DMA是否支持SRC频道？

从460的第95页，
"20.1.1 I/O channels
SRC块将两个24位通道转换为
a stereo pair or as two mono channels. The PCM linear
data pairs are received on SRC_IN and the output is
2x24位在src_out左对齐“，
which says SRC support two channels; and from "Figure 56: Sample rate Converter block diagram", we have both channel registers:
PCM_IN1[], PCM_IN2[]/ SRC_IN1_REG[], SRC_IN2_REG[] /SRC_OUT1_REG,SRC_OUT2_REG

from Page 74 of 460, "Table 29: DMA served peripherals", it says the served peripheral includes PCM RX/TX, SRC RX/TX, but it
doesn't explicitly say Both PCM,SRC channels.

and from Page 426 of 460, "Table 756: DMA_REQ_MUX_REG (0x50003580)", it seems that only one DMA channel for SRC_TX,
so I wonder how to feed both SRC channels into one DMA channel, or it only support one SRC channel map to one DMA channel at one time.

从代码“hw_dma.h”
typedef enum {
HW_DMA_TRIG_SPI_RXTX = 0x0,
hw_dma_trig_spi2_rxtx = 0x1，
HW_DMA_TRIG_UART_RXTX = 0x2,
HW_DMA_TRIG_UART2_RXTX = 0x3,
HW_DMA_TRIG_I2C_RXTX = 0x4,
HW_DMA_TRIG_I2C2_RXTX = 0x5,
hw_dma_trig_usb_rxtx = 0x6，
HW_DMA_TRIG_I2S_LEFTRIGHT = 0x8,
HW_DMA_TRIG_PDM_LEFTRIGHT = 0 x9,
HW_DMA_TRIG_FTDF_RXTX = 0xA,
hw_dma_trig_ecc_rxtx = 0xb，
hw_dma_trig_adc = 0xc，
hw_dma_trig_none = 0xf.
hw_dma_trig;

I2S_LEFTRIGHT, PDM_LEFTRIGHT indicates both channels, but don't know how to feed both channels into one DMA channel, and does the PDM represent
SRC as well? or only means PDM?

2) A related question, since PCM and SRC has two channels as describled above,
从460的第431页，“表767：APU_MUX_REG（0x5000401C）”，
Bit Mode Symbol Description Reset
6 R / W PDM1_MUX_IN PDM1输入MUX
0 = src1_mux_in.
1 = PDM输入

5:3 R/W PCM1_MUX_IN PCM1 input mux
0 = off
1 = SRC1 output
2 = PCM输出寄存器

2:0 R/W SRC1_MUX_IN SRC1 input mux
0 = off
1 = PCM output
2 = SRC1 input registers
This table is confusing to me,
1）位2：0，设置为1以将PCM输出路由到SRC输入？
but from page 95 of 460, "Figure 56:Sample rate Converter block diagram", it says routing PCM_IN1/PCM_IN2 to SRC_IN,

2）位5：3，设置为1到SRC1输出的路由，设置为2到PCM输出寄存器的路由，
again, from page 95 of 460, "Figure 56:Sample rate Converter block diagram", it says routing SRC_OUT1 to SRC_OUT1_REG or to PCM_OUT

if my description is confusing as well, in other way, I want to implement the scenario of PCM_IN to USB:
来自“表44：典型的SRC用例”FR Page 96
describled. And
如何配置APU_MUX_REG将通道PCM_IN1_DATA - > SRC_OUT1_REG，PCM_IN2_DATA - > SRC_OUT2_REG分开？