[PATCH v3 3/3] PCI: apple: Fix #PERST polarity

From: Marc Zyngier
Date: Tue Nov 23 2021 - 13:06:50 EST


Now that #PERST is properly defined as active-low in the device tree,
fix the driver to correctly drive the line indemendently of the
implied polarity.

Fixes: 1e33888fbe44 ("PCI: apple: Add initial hardware bring-up")
Suggested-by: Pali Rohár <pali@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
drivers/pci/controller/pcie-apple.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c
index 957960a733c4..03bc56f39be5 100644
--- a/drivers/pci/controller/pcie-apple.c
+++ b/drivers/pci/controller/pcie-apple.c
@@ -540,7 +540,7 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie,
rmw_set(PORT_APPCLK_EN, port->base + PORT_APPCLK);

/* Engage #PERST before setting up the clock */
- gpiod_set_value(reset, 0);
+ gpiod_set_value(reset, 1);

ret = apple_pcie_setup_refclk(pcie, port);
if (ret < 0)
@@ -551,7 +551,7 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie,

/* Deassert #PERST */
rmw_set(PORT_PERST_OFF, port->base + PORT_PERST);
- gpiod_set_value(reset, 1);
+ gpiod_set_value(reset, 0);

/* Wait for 100ms after #PERST deassertion (PCIe r2.0, 6.6.1) */
msleep(100);
--
2.30.2