aboutsummaryrefslogtreecommitdiff
path: root/Kconfig
diff options
context:
space:
mode:
authordillon min2020-05-25 11:45:47 +0800
committerMark Brown2020-05-25 15:56:16 +0100
commit61367d0b8f5edf5146059ba8b79ce4e4485340b2 (patch)
tree70298ea8535a70dbc71db49702725f0ad20dc525 /Kconfig
parent8fede89f853a7bfc671f9d8f069ccfe4190061f3 (diff)
spi: stm32: Add 'SPI_SIMPLEX_RX', 'SPI_3WIRE_RX' support for stm32f4
in l3gd20 driver startup, there is a setup failed error return from stm32 spi driver " [ 2.687630] st-gyro-spi spi0.0: supply vdd not found, using dummy regulator [ 2.696869] st-gyro-spi spi0.0: supply vddio not found, using dummy regulator [ 2.706707] spi_stm32 40015000.spi: SPI transfer setup failed [ 2.713741] st-gyro-spi spi0.0: SPI transfer failed: -22 [ 2.721096] spi_master spi0: failed to transfer one message from queue [ 2.729268] iio iio:device0: failed to read Who-Am-I register. [ 2.737504] st-gyro-spi: probe of spi0.0 failed with error -22 " after debug into spi-stm32 driver, st-gyro-spi split two steps to read l3gd20 id first: send command to l3gd20 with read id command in tx_buf, rx_buf is null. second: read id with tx_buf is null, rx_buf not null. so, for second step, stm32 driver recongise this process as 'SPI_SIMPLE_RX' from stm32_spi_communication_type(), but there is no related process for this type in stm32f4_spi_set_mode(), then we get error from stm32_spi_transfer_one_setup(). we can use two method to fix this bug. 1, use stm32 spi's "In unidirectional receive-only mode (BIDIMODE=0 and RXONLY=1)". but as our code running in sdram, the read latency is too large to get so many receive overrun error in interrupts handler. 2, use stm32 spi's "In full-duplex (BIDIMODE=0 and RXONLY=0)", as tx_buf is null, so add flag 'SPI_MASTER_MUST_TX' to spi master. Change since V4: 1 remove dummy data sent out by stm32 spi driver 2 add flag 'SPI_MASTER_MUST_TX' to spi master Signed-off-by: dillon min <dillon.minfei@gmail.com> Link: https://lore.kernel.org/r/1590378348-8115-8-git-send-email-dillon.minfei@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'Kconfig')
0 files changed, 0 insertions, 0 deletions