SPI read failing on STM32F4 device

I'm using the STM32F4 trying to read over SPI. Debug environments is Visual Studio with the VisualGDB plugin. The spi config is as follows. 8-bit frames, MSB first, using GPIOA/B for the SPI signals

void spiInit() {

RCC->AHB1ENR |= 3;          //enable gpioA/B clock
RCC->APB2ENR |= 0x1000;     //enable SPI1 clock (bit 12)

// configure A5 for SCLK
GPIOA->MODER &= ~0x00000C00;    //clear pin mode for pin 5
GPIOA->MODER |=  0x00000800;    //alternate function mode for pin 5
GPIOA->AFR[0] &= ~0x00F00000;   //clear alternate mode
GPIOA->AFR[0] |=  0x00500000;   //setup pins 5 for AF5

// configure B4 for MISO
GPIOB->MODER &= ~0x00000300;    //clear pin mode for pin 4
GPIOB->MODER |=  0x00000200;    //alternate function mode for pin 5
GPIOB->AFR[0] &= ~0x000F0000;   //clear alternate mode
GPIOB->AFR[0] |=  0x00050000;   //setup pins 4 for AF5

// configure B5 for MOSI
GPIOB->MODER &= ~0x00000C00;    //clear pin mode for pin 5
GPIOB->MODER |=  0x00000800;    //alternate function mode for pin 5
GPIOB->AFR[0] &= ~0x00F00000;   //clear alternate mode
GPIOB->AFR[0] |=  0x00500000;   //setup pins 5 for AF5

// configure A15 for output SS
GPIOA->MODER &= ~0xC0000000;    //clear PA15 function bits
GPIOA->MODER |=  0x40000000;    //set PA15 (SS) as output

SPI1->CR1 = 0x31E; //8-bit frames
SPI1->CR2 = 0; //mostly read/status/interrupt config
SPI1->CR1 |= 0x40; //enable SPI1
GPIOA->BSRR = 0x00008000;   //deassert SS
}

Writes are fine, data is loaded correctly to slave and it responds as expected, reads from the slave however are not working. I can see that MISO looks good on the bus when i look at the waveforms, but it's not picked up by the Master.

After a few attempts at watching the SPI status-register flags, (getting the results described above) I'm using a utility function that i saw on another SO question (here). The data always reads 0 and i am confused, the code waits for the receive buffer to fill, but there seems to nothing there when it is read.

uint8_t SPI_ReadWrite8(SPI_TypeDef *spi, uint8_t data)
{
    while(!(spi -> SR & SPI_SR_TXE));     //Wait for tx buffer to empty
    *(volatile uint8_t *)&spi->DR = data; //Send data 
    while (!(spi -> SR & SPI_SR_RXNE));   //Wait for rx buffer to fill
    return *(volatile uint8_t *)&spi->DR;
}

Any ideas what i'm missing?