(core/mcp3008/pio): Attempt to set SPI clock speed

src/core/mcp3008/pio/mcp3008_pio.c

@@ -1,13 +1,19 @@
 #include "mcp3008_pio.h"
 
+// clk_sys enum
+#include "hardware/clocks.h"
+
 spi_dual_inst mcp3008_init_pio(PIO pio, uint baudrate, spi_pinout_t *pinout)
 {
  pio_spi_inst_t spi = {
  .pio = pio, // pio to use (pio0, pio1)
  .sm = pio_claim_unused_sm(pio, true) // claim first free state machine
  };
 
- float clkdiv = 31.25f; // 1 MHz @ 125 clk_sys
+ // Based on: https://medium.com/geekculture/raspberry-pico-programming-with-pio-state-machines-e4610e6b0f29
+ // *Should* make the spi clock speed correct.
+ float clock_divider = (float)clock_get_hz(clk_sys) / SPI_CLOCK_SPEED;
+ // float clkdiv = 31.25f; // 1 MHz @ 125 clk_sys
 
  uint cpha0_prog_offs = pio_add_program(spi.pio, &spi_cpha0_program);
 
@@ -16,7 +22,7 @@ spi_dual_inst mcp3008_init_pio(PIO pio, uint baudrate, spi_pinout_t *pinout)
  spi.sm, // state machine (num)
  cpha0_prog_offs, // program offsets
  8, // number of bits per SPI frame
- clkdiv,  // Clock divider
+ clock_divider, // Clock divider
  0, // cpha
  1, // cpol
  pinout->sck, // SCK pin,