spi: mchp-pci1xxxx: Fix improper implementation of disabling chip select lines

Hardware does not have support to disable individual chip select lines.
Disable all chip select lines by using SPI_FORCE_CE bit.

Fixes: 1cc0cbea7167 ("spi: microchip: pci1xxxx: Add driver for SPI controller of PCI1XXXX PCIe switch")
Signed-off-by: Tharun Kumar P <tharunkumar.pasumarthi@microchip.com>
Link: https://lore.kernel.org/r/20230404171613.1336093-4-tharunkumar.pasumarthi@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-pci1xxxx.c b/drivers/spi/spi-pci1xxxx.c
index 82d4bfe..4445d82 100644 (file)
--- a/drivers/spi/spi-pci1xxxx.c
+++ b/drivers/spi/spi-pci1xxxx.c
@@ -114,17 +114,14 @@ static void pci1xxxx_spi_set_cs(struct spi_device *spi, bool enable)
 
        /* Set the DEV_SEL bits of the SPI_MST_CTL_REG */
        regval = readl(par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst));
-       if (enable) {
+       if (!enable) {
+               regval |= SPI_FORCE_CE;
                regval &= ~SPI_MST_CTL_DEVSEL_MASK;
                regval |= (spi_get_chipselect(spi, 0) << 25);
-               writel(regval,
-                      par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst));
        } else {
-               regval &= ~(spi_get_chipselect(spi, 0) << 25);
-               writel(regval,
-                      par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst));
-
+               regval &= ~SPI_FORCE_CE;
        }
+       writel(regval, par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst));
 }
 
 static u8 pci1xxxx_get_clock_div(u32 hz)
@@ -199,7 +196,7 @@ static int pci1xxxx_spi_transfer_one(struct spi_controller *spi_ctlr,
                        else
                                regval &= ~SPI_MST_CTL_MODE_SEL;
 
-                       regval |= ((clkdiv << 5) | SPI_FORCE_CE);
+                       regval |= (clkdiv << 5);
                        regval &= ~SPI_MST_CTL_CMD_LEN_MASK;
                        regval |= (len << 8);
                        writel(regval, par->reg_base +
@@ -223,10 +220,6 @@ static int pci1xxxx_spi_transfer_one(struct spi_controller *spi_ctlr,
                        }
                }
        }
-
-       regval = readl(par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst));
-       regval &= ~SPI_FORCE_CE;
-       writel(regval, par->reg_base + SPI_MST_CTL_REG_OFFSET(p->hw_inst));
        p->spi_xfer_in_progress = false;
 
        return 0;