From 1a348179dd38d9c68fe9650e9f9a020ab1f5c824 Mon Sep 17 00:00:00 2001
From: Alex Demenchuk <alexander.demenchuk@gmail.com>
Date: Thu, 11 Oct 2018 17:44:35 -0400
Subject: [PATCH] Fixed command and address in LSB mode
---
core/include/esp/spi.h | 24 ++++++++++++++++++++----
1 file changed, 20 insertions(+), 4 deletions(-)
diff --git a/core/include/esp/spi.h b/core/include/esp/spi.h
index 9ce68fb..8c7620d 100644
--- a/core/include/esp/spi.h
+++ b/core/include/esp/spi.h
@@ -293,9 +293,18 @@ static inline void spi_set_command(uint8_t bus, uint8_t bits, uint16_t data)
{
if (!bits) return;
- SPI(bus).USER0 |= SPI_USER0_COMMAND; //enable COMMAND function in SPI module
- uint16_t command = data << (16 - bits); //align command data to high bits
- command = ((command >> 8) & 0xff) | ((command << 8) & 0xff00); //swap byte order
+ SPI(bus).USER0 |= SPI_USER0_COMMAND; //enable COMMAND function in SPI module
+ uint16_t command;
+ // Commands are always sent using little endian byte order
+ if (!spi_get_msb(bus)) {
+ // "data" are natively little endian, with LSB bit order
+ // this makes all bits of the command ready to be sent as-is
+ command = data;
+ } else {
+ // MSB
+ command = data << (16 - bits); //align command data to high bits
+ command = ((command >> 8) & 0xff) | ((command << 8) & 0xff00); //swap byte order
+ }
SPI(bus).USER2 = SET_FIELD(SPI(bus).USER2, SPI_USER2_COMMAND_BITLEN, --bits);
SPI(bus).USER2 = SET_FIELD(SPI(bus).USER2, SPI_USER2_COMMAND_VALUE, command);
}
@@ -320,7 +329,14 @@ static inline void spi_set_address(uint8_t bus, uint8_t bits, uint32_t data)
if (!bits) return;
SPI(bus).USER0 |= SPI_USER0_ADDR; //enable ADDRess function in SPI module
- SPI(bus).ADDR = data << (32 - bits); //align address data to high bits
+ // addresses are always sent using big endian byte order
+ if (spi_get_msb(bus)) {
+ SPI(bus).ADDR = data << (32 - bits); //align address data to high bits
+ } else {
+ // swap bytes from native little to command's big endian order
+ // bits in each byte are already arranged properly for LSB
+ SPI(bus).ADDR = (data & 0xff) << 24 | (data & 0xff00) << 8 | ((data >> 8) & 0xff00) | ((data >> 24) & 0xff);
+ }
SPI(bus).USER1 = SET_FIELD(SPI(bus).USER1, SPI_USER1_ADDR_BITLEN, --bits);
}