Fix coments and add macro for SPI

diff --git a/include/drivers/ssp.h b/include/drivers/ssp.h
index 3f765ef..bbbfe7d 100644 (file)
--- a/include/drivers/ssp.h
+++ b/include/drivers/ssp.h
@@ -57,7 +57,7 @@ void spi_release_mutex(uint8_t ssp_num);
 /***************************************************************************** */
 /* This function is used to transfer a word (4 to 16 bits) to AND from a device
  * As the SPI bus is full duplex, data can flow in both directions, but the clock is
- *   always provided by the master. The SPI clock cannont be activated without sending
+ *   always provided by the master. The SPI clock cannot be activated without sending
  *   data, which means we must send data to the device when we want to read data from
  *   the device.
  * Note : the SSP device number is not checked, thus a value above the number of SSP
@@ -82,6 +82,8 @@ uint16_t spi_transfer_single_frame(uint8_t ssp_num, uint16_t data);
  *             pointed by "data_out" for each frame. If NULL, then the content of data_in
  *             will be used.
  *  data_in : buffer for read data. If NULL, read data will be discarded.
+ *  width : used to differentiate between size up to 8 bits and above 8 bits.
+ *          Use LPC_SSP_WORD_LEN(x) macro.
  * Returns the number of data words transfered or negative value on error.
  * As the SPI bus is full duplex, data can flow in both directions, but the clock is
  *   always provided by the master. The SPI clock cannont be activated without sending
@@ -93,6 +95,8 @@ uint16_t spi_transfer_single_frame(uint8_t ssp_num, uint16_t data);
 int spi_transfer_multiple_frames(uint8_t ssp_num, void* data_out, void* data_in, int size, int width);
 
 
+#define LPC_SSP_WORD_LEN(x)  (x)
+#define LPC_SSP_MHz(x) ((x) * 1000 * 1000)
 
 /***************************************************************************** */
 void ssp_clk_update(void);
@@ -104,8 +108,8 @@ void ssp_clk_update(void);
  * Parameters :
  *  frame_type is SPI, TI or MICROWIRE (use apropriate defines for this one).
  *     LPC_SSP_FRAME_SPI - LPC_SSP_FRAME_TI - LPC_SSP_FRAME_MICROWIRE).
- *  data_width is a number between 4 and 16.
- *  rate : The bit rate, in Hz.
+ *  data_width is a number between 4 and 16. Use LPC_SSP_WORD_LEN(x) macro for this one.
+ *  rate : The bit rate, in Hz. Use LPC_SSP_MHz(x) macro to get Hz from MHz value.
  * The SPI Chip Select is not handled by the SPI driver in master SPI mode as it's
  *   handling highly depends on the device on the other end of the wires. Use a GPIO
  *   to activate the device's chip select (usually active low)