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spi_master: fix the command and address field when LSB_FIRST enabled

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Resolves https://github.com/espressif/esp-idf/issues/2444.
This commit is contained in:
Michael (XIAO Xufeng) 2018-09-28 11:36:14 +08:00
parent 97219eeb31
commit b9f10a71ea
1 changed files with 21 additions and 1 deletions
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22
components/driver/spi_master.c
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@ -727,7 +727,11 @@ static void SPI_MASTER_ISR_ATTR spi_intr(void *arg)
host->hw->user.usr_addr=addrlen?1:0;
host->hw->user.usr_command=cmdlen?1:0;
// output command will be sent from bit 7 to 0 of command_value, and then bit 15 to 8 of the same register field.
if ((dev->cfg.flags & SPI_DEVICE_TXBIT_LSBFIRST)==0) {
/* Output command will be sent from bit 7 to 0 of command_value, and
* then bit 15 to 8 of the same register field. Shift and swap to send
* more straightly.
*/
uint16_t command = trans->cmd << (16-cmdlen); //shift to MSB
host->hw->user2.usr_command_value = (command>>8)|(command<<8); //swap the first and second byte
// shift the address to MSB of addr (and maybe slv_wr_status) register.
@ -738,6 +742,22 @@ static void SPI_MASTER_ISR_ATTR spi_intr(void *arg)
} else {
host->hw->addr = trans->addr << (32 - addrlen);
}
} else {
/* The output command start from bit0 to bit 15, kept as is.
* The output address start from the LSB of the highest byte, i.e.
* addr[24] -> addr[31]
* ...
* addr[0] -> addr[7]
* slv_wr_status[24] -> slv_wr_status[31]
* ...
* slv_wr_status[0] -> slv_wr_status[7]
* So swap the byte order to let the LSB sent first.
*/
host->hw->user2.usr_command_value = trans->cmd;
uint64_t addr = __builtin_bswap64(trans->addr);
host->hw->addr = addr>>32;
host->hw->slv_wr_status = addr;
}
host->hw->user.usr_mosi=( (!(dev->cfg.flags & SPI_DEVICE_HALFDUPLEX) && trans_buf->buffer_to_rcv) || trans_buf->buffer_to_send)?1:0;
host->hw->user.usr_miso=(trans_buf->buffer_to_rcv)?1:0;