6.1-stable review patch. If anyone has any objections, please let me know.
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From: Alexander Dahl ada@thorsis.com
commit 329ca3eed4a9a161515a8714be6ba182321385c7 upstream.
Previously the MR and SCR registers were just set with the supposedly required values, from cached register values (cached reg content initialized to zero).
All parts fixed here did not consider the current register (cache) content, which would make future support of cs_setup, cs_hold, and cs_inactive impossible.
Setting SCBR in atmel_qspi_setup() erases a possible DLYBS setting from atmel_qspi_set_cs_timing(). The DLYBS setting is applied by ORing over the current setting, without resetting the bits first. All writes to MR did not consider possible settings of DLYCS and DLYBCT.
Signed-off-by: Alexander Dahl ada@thorsis.com Fixes: f732646d0ccd ("spi: atmel-quadspi: Add support for configuring CS timing") Link: https://patch.msgid.link/20240918082744.379610-2-ada@thorsis.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/spi/atmel-quadspi.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)
--- a/drivers/spi/atmel-quadspi.c +++ b/drivers/spi/atmel-quadspi.c @@ -388,9 +388,9 @@ static int atmel_qspi_set_cfg(struct atm * If the QSPI controller is set in regular SPI mode, set it in * Serial Memory Mode (SMM). */ - if (aq->mr != QSPI_MR_SMM) { - atmel_qspi_write(QSPI_MR_SMM, aq, QSPI_MR); - aq->mr = QSPI_MR_SMM; + if (!(aq->mr & QSPI_MR_SMM)) { + aq->mr |= QSPI_MR_SMM; + atmel_qspi_write(aq->scr, aq, QSPI_MR); }
/* Clear pending interrupts */ @@ -545,7 +545,8 @@ static int atmel_qspi_setup(struct spi_d if (ret < 0) return ret;
- aq->scr = QSPI_SCR_SCBR(scbr); + aq->scr &= ~QSPI_SCR_SCBR_MASK; + aq->scr |= QSPI_SCR_SCBR(scbr); atmel_qspi_write(aq->scr, aq, QSPI_SCR);
pm_runtime_mark_last_busy(ctrl->dev.parent); @@ -578,6 +579,7 @@ static int atmel_qspi_set_cs_timing(stru if (ret < 0) return ret;
+ aq->scr &= ~QSPI_SCR_DLYBS_MASK; aq->scr |= QSPI_SCR_DLYBS(cs_setup); atmel_qspi_write(aq->scr, aq, QSPI_SCR);
@@ -593,8 +595,8 @@ static void atmel_qspi_init(struct atmel atmel_qspi_write(QSPI_CR_SWRST, aq, QSPI_CR);
/* Set the QSPI controller by default in Serial Memory Mode */ - atmel_qspi_write(QSPI_MR_SMM, aq, QSPI_MR); - aq->mr = QSPI_MR_SMM; + aq->mr |= QSPI_MR_SMM; + atmel_qspi_write(aq->mr, aq, QSPI_MR);
/* Enable the QSPI controller */ atmel_qspi_write(QSPI_CR_QSPIEN, aq, QSPI_CR);