From b48b9488e3180b173f37782a348b76ea6bff2c48 Mon Sep 17 00:00:00 2001 From: Lars-Peter Clausen Date: Thu, 10 Jul 2014 11:26:29 +0200 Subject: [PATCH] spi: cadence: Configure SPI clock in the prepare_message() callback Currently the cadence SPI driver does the SPI clock configuration (setup CPOL and CPHA) in the prepare_transfer_hardware() callback. The prepare_transfer_hardware() callback is only called though when the controller transitions from a idle state to a non-idle state. Such a transitions happens when the message queue goes from empty to non-empty. If multiple messages from different SPI slaves with different clock settings are in the message queue the clock settings will not be properly updated when switching from one slave device to another. Instead do the updating of the clock configuration in the prepare_message() callback which will be called for each individual message. Signed-off-by: Lars-Peter Clausen Signed-off-by: Mark Brown --- drivers/spi/spi-cadence.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c index f55702937052..3312eccb18c1 100644 --- a/drivers/spi/spi-cadence.c +++ b/drivers/spi/spi-cadence.c @@ -382,6 +382,12 @@ static irqreturn_t cdns_spi_irq(int irq, void *dev_id) return status; } +static int cdns_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + cdns_spi_config_clock_mode(msg->spi); + return 0; +} /** * cdns_transfer_one - Initiates the SPI transfer @@ -428,8 +434,6 @@ static int cdns_prepare_transfer_hardware(struct spi_master *master) { struct cdns_spi *xspi = spi_master_get_devdata(master); - cdns_spi_config_clock_mode(master->cur_msg->spi); - cdns_spi_write(xspi, CDNS_SPI_ER_OFFSET, CDNS_SPI_ER_ENABLE_MASK); @@ -544,6 +548,7 @@ static int cdns_spi_probe(struct platform_device *pdev) xspi->is_decoded_cs = 0; master->prepare_transfer_hardware = cdns_prepare_transfer_hardware; + master->prepare_message = cdns_prepare_message; master->transfer_one = cdns_transfer_one; master->unprepare_transfer_hardware = cdns_unprepare_transfer_hardware; master->set_cs = cdns_spi_chipselect; -- 2.39.5