From e81cd07dcf50ef4811f6667dba89c5614278cbdd Mon Sep 17 00:00:00 2001 From: Kamal Dasu Date: Fri, 8 Oct 2021 16:36:03 -0400 Subject: [PATCH] spi: bcm-qspi: add support for 3-wire mode for half duplex transfer This change configures the MSPI controller to use 3-wire interface when a slave device devictree nodes indicates this via the optional property. Signed-off-by: Kamal Dasu Acked-by: Florian Fainelli Link: https://lore.kernel.org/r/20211008203603.40915-4-kdasu.kdev@gmail.com Signed-off-by: Mark Brown --- drivers/spi/spi-bcm-qspi.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c index c7c467f..6cb2019 100644 --- a/drivers/spi/spi-bcm-qspi.c +++ b/drivers/spi/spi-bcm-qspi.c @@ -103,6 +103,7 @@ #define MSPI_MASTER_BIT BIT(7) #define MSPI_NUM_CDRAM 16 +#define MSPI_CDRAM_OUTP BIT(8) #define MSPI_CDRAM_CONT_BIT BIT(7) #define MSPI_CDRAM_BITSE_BIT BIT(6) #define MSPI_CDRAM_DT_BIT BIT(5) @@ -122,6 +123,8 @@ #define MSPI_SPCR3_DAM_8BYTE 0 #define MSPI_SPCR3_DAM_16BYTE (BIT(2) | BIT(4)) #define MSPI_SPCR3_DAM_32BYTE (BIT(3) | BIT(5)) +#define MSPI_SPCR3_HALFDUPLEX BIT(6) +#define MSPI_SPCR3_HDOUTTYPE BIT(7) #define MSPI_SPCR3_DATA_REG_SZ BIT(8) #define MSPI_SPCR3_CPHARX BIT(9) @@ -613,6 +616,9 @@ static void bcm_qspi_hw_set_parms(struct bcm_qspi *qspi, /* enable fastbr */ spcr |= MSPI_SPCR3_FASTBR; + if (xp->mode & SPI_3WIRE) + spcr |= MSPI_SPCR3_HALFDUPLEX | MSPI_SPCR3_HDOUTTYPE; + if (bcm_qspi_has_sysclk_108(qspi)) { /* SYSCLK_108 */ spcr |= MSPI_SPCR3_SYSCLKSEL_108; @@ -940,6 +946,10 @@ static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi) mspi_cdram |= ((tp.trans->bits_per_word <= 8) ? 0 : MSPI_CDRAM_BITSE_BIT); + /* set 3wrire halfduplex mode data from master to slave */ + if ((spi->mode & SPI_3WIRE) && tp.trans->tx_buf) + mspi_cdram |= MSPI_CDRAM_OUTP; + if (has_bspi(qspi)) mspi_cdram &= ~1; else @@ -1480,7 +1490,8 @@ int bcm_qspi_probe(struct platform_device *pdev, qspi->master = master; master->bus_num = -1; - master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_RX_DUAL | SPI_RX_QUAD; + master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_RX_DUAL | SPI_RX_QUAD | + SPI_3WIRE; master->setup = bcm_qspi_setup; master->transfer_one = bcm_qspi_transfer_one; master->mem_ops = &bcm_qspi_mem_ops; -- 2.7.4