From 1c384327383de13223186ec138c57cb49fa1efea Mon Sep 17 00:00:00 2001 From: Kamal Dasu Date: Thu, 26 Apr 2018 14:48:00 -0400 Subject: [PATCH] spi: bcm-qspi: Avoid setting MSPI_CDRAM_PCS for spi-nor master commit 5eb9a07a4ae1008b67d8bcd47bddb3dae97456b7 upstream. Added fix for probing of spi-nor device non-zero chip selects. Set MSPI_CDRAM_PCS (peripheral chip select) with spi master for MSPI controller and not for MSPI/BSPI spi-nor master controller. Ensure setting of cs bit in chip select register on chip select change. Fixes: fa236a7ef24048 ("spi: bcm-qspi: Add Broadcom MSPI driver") Signed-off-by: Kamal Dasu Signed-off-by: Mark Brown Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/spi/spi-bcm-qspi.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c index 7d629b4e1ecc..77966e291ae6 100644 --- a/drivers/spi/spi-bcm-qspi.c +++ b/drivers/spi/spi-bcm-qspi.c @@ -543,16 +543,19 @@ static void bcm_qspi_disable_bspi(struct bcm_qspi *qspi) static void bcm_qspi_chip_select(struct bcm_qspi *qspi, int cs) { - u32 data = 0; + u32 rd = 0; + u32 wr = 0; - if (qspi->curr_cs == cs) - return; if (qspi->base[CHIP_SELECT]) { - data = bcm_qspi_read(qspi, CHIP_SELECT, 0); - data = (data & ~0xff) | (1 << cs); - bcm_qspi_write(qspi, CHIP_SELECT, 0, data); + rd = bcm_qspi_read(qspi, CHIP_SELECT, 0); + wr = (rd & ~0xff) | (1 << cs); + if (rd == wr) + return; + bcm_qspi_write(qspi, CHIP_SELECT, 0, wr); usleep_range(10, 20); } + + dev_dbg(&qspi->pdev->dev, "using cs:%d\n", cs); qspi->curr_cs = cs; } @@ -770,8 +773,13 @@ static int write_to_hw(struct bcm_qspi *qspi, struct spi_device *spi) dev_dbg(&qspi->pdev->dev, "WR %04x\n", val); } mspi_cdram = MSPI_CDRAM_CONT_BIT; - mspi_cdram |= (~(1 << spi->chip_select) & - MSPI_CDRAM_PCS); + + if (has_bspi(qspi)) + mspi_cdram &= ~1; + else + mspi_cdram |= (~(1 << spi->chip_select) & + MSPI_CDRAM_PCS); + mspi_cdram |= ((tp.trans->bits_per_word <= 8) ? 0 : MSPI_CDRAM_BITSE_BIT); -- 2.20.1