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Change SPI_USE_RXDATA->SPI_TRANS_USE_RXDATA and SPI_USE_TXDATA->SPI_TRANS_USE_TXDATA on documentation

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Closes https://github.com/espressif/esp-idf/pull/2802
This commit is contained in:
Oleg Antonyan
2018-12-07 09:34:15 +02:00
committed by Mahavir Jain
parent 058c6afd3c
commit 4430456b64
2 changed files with 6 additions and 6 deletions
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4
components/driver/include/driver/spi_master.h
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@@ -133,11 +133,11 @@ struct spi_transaction_t {
void *user; ///< User-defined variable. Can be used to store eg transaction ID. void *user; ///< User-defined variable. Can be used to store eg transaction ID.
union { union {
const void *tx_buffer; ///< Pointer to transmit buffer, or NULL for no MOSI phase const void *tx_buffer; ///< Pointer to transmit buffer, or NULL for no MOSI phase
uint8_t tx_data[4]; ///< If SPI_USE_TXDATA is set, data set here is sent directly from this variable. uint8_t tx_data[4]; ///< If SPI_TRANS_USE_TXDATA is set, data set here is sent directly from this variable.
}; };
union { union {
void *rx_buffer; ///< Pointer to receive buffer, or NULL for no MISO phase. Written by 4 bytes-unit if DMA is used. void *rx_buffer; ///< Pointer to receive buffer, or NULL for no MISO phase. Written by 4 bytes-unit if DMA is used.
uint8_t rx_data[4]; ///< If SPI_USE_RXDATA is set, data is received directly to this variable uint8_t rx_data[4]; ///< If SPI_TRANS_USE_RXDATA is set, data is received directly to this variable
}; };
} ; //the rx data should start from a 32-bit aligned address to get around dma issue. } ; //the rx data should start from a 32-bit aligned address to get around dma issue.

8
docs/en/api-reference/peripherals/spi_master.rst
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@@ -78,8 +78,8 @@ and/or address. This is reflected in the device configuration: when the ``comman
fields are set to zero, no command or address phase is done. fields are set to zero, no command or address phase is done.
Something similar is true for the read and write phase: not every transaction needs both data to be written Something similar is true for the read and write phase: not every transaction needs both data to be written
as well as data to be read. When ``rx_buffer`` is NULL (and SPI_USE_RXDATA) is not set) the read phase as well as data to be read. When ``rx_buffer`` is NULL (and SPI_TRANS_USE_RXDATA) is not set) the read phase
is skipped. When ``tx_buffer`` is NULL (and SPI_USE_TXDATA) is not set) the write phase is skipped. is skipped. When ``tx_buffer`` is NULL (and SPI_TRANS_USE_TXDATA) is not set) the write phase is skipped.
The driver offers two different kinds of transactions: the interrupt The driver offers two different kinds of transactions: the interrupt
transactions and the polling transactions. Each device can choose one kind of transactions and the polling transactions. Each device can choose one kind of
@@ -205,8 +205,8 @@ Tips
1. Transactions with small amount of data: 1. Transactions with small amount of data:
Sometimes, the amount of data is very small making it less than optimal allocating a separate buffer Sometimes, the amount of data is very small making it less than optimal allocating a separate buffer
for it. If the data to be transferred is 32 bits or less, it can be stored in the transaction struct for it. If the data to be transferred is 32 bits or less, it can be stored in the transaction struct
itself. For transmitted data, use the ``tx_data`` member for this and set the ``SPI_USE_TXDATA`` flag itself. For transmitted data, use the ``tx_data`` member for this and set the ``SPI_TRANS_USE_TXDATA`` flag
on the transmission. For received data, use ``rx_data`` and set ``SPI_USE_RXDATA``. In both cases, do on the transmission. For received data, use ``rx_data`` and set ``SPI_TRANS_USE_RXDATA``. In both cases, do
not touch the ``tx_buffer`` or ``rx_buffer`` members, because they use the same memory locations not touch the ``tx_buffer`` or ``rx_buffer`` members, because they use the same memory locations
as ``tx_data`` and ``rx_data``. as ``tx_data`` and ``rx_data``.