From 3d71746c420c1c1c27cf5c4e48f8fa0a6cfdc185 Mon Sep 17 00:00:00 2001 From: Baruch Siach Date: Wed, 3 Oct 2018 15:49:43 +0300 Subject: PCI: armada8k: Add support for gpio controlled reset signal Add support for the gpio reset signal binding as described in the designware-pcie.txt DT binding document. Both the documented 'reset-gpio' property name and the more standard 'reset-gpios' name are supported. Signed-off-by: Baruch Siach Signed-off-by: Lorenzo Pieralisi Acked-by: Thomas Petazzoni --- drivers/pci/controller/dwc/pcie-armada8k.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'drivers/pci') diff --git a/drivers/pci/controller/dwc/pcie-armada8k.c b/drivers/pci/controller/dwc/pcie-armada8k.c index 0c389a30ef5d..b171b6bc15c8 100644 --- a/drivers/pci/controller/dwc/pcie-armada8k.c +++ b/drivers/pci/controller/dwc/pcie-armada8k.c @@ -22,6 +22,7 @@ #include #include #include +#include #include "pcie-designware.h" @@ -29,6 +30,7 @@ struct armada8k_pcie { struct dw_pcie *pci; struct clk *clk; struct clk *clk_reg; + struct gpio_desc *reset_gpio; }; #define PCIE_VENDOR_REGS_OFFSET 0x8000 @@ -137,6 +139,12 @@ static int armada8k_pcie_host_init(struct pcie_port *pp) struct dw_pcie *pci = to_dw_pcie_from_pp(pp); struct armada8k_pcie *pcie = to_armada8k_pcie(pci); + if (pcie->reset_gpio) { + /* assert and then deassert the reset signal */ + gpiod_set_value_cansleep(pcie->reset_gpio, 1); + msleep(100); + gpiod_set_value_cansleep(pcie->reset_gpio, 0); + } dw_pcie_setup_rc(pp); armada8k_pcie_establish_link(pcie); @@ -249,6 +257,14 @@ static int armada8k_pcie_probe(struct platform_device *pdev) goto fail_clkreg; } + /* Get reset gpio signal and hold asserted (logically high) */ + pcie->reset_gpio = devm_gpiod_get_optional(dev, "reset", + GPIOD_OUT_HIGH); + if (IS_ERR(pcie->reset_gpio)) { + ret = PTR_ERR(pcie->reset_gpio); + goto fail_clkreg; + } + platform_set_drvdata(pdev, pcie); ret = armada8k_add_pcie_port(pcie, pdev); -- cgit v1.2.3-59-g8ed1b