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| author | Andrey Smirnov <andrew.smirnov@gmail.com> | 2019-01-16 18:16:55 -0800 |
|---|---|---|
| committer | Sascha Hauer <s.hauer@pengutronix.de> | 2019-01-18 09:43:10 +0100 |
| commit | 2d34376bc1a83fa118478675ca01a5d5bd03326b (patch) | |
| tree | e96a0b0d09c23e8e90ab30efd7c01614f759d808 /drivers/pci | |
| parent | 6106878268daef9796553201d134fd413e888695 (diff) | |
| download | barebox-2d34376bc1a83fa118478675ca01a5d5bd03326b.tar.gz barebox-2d34376bc1a83fa118478675ca01a5d5bd03326b.tar.xz | |
PCI: imx6: Allow probe deferral by reset GPIO
Port of a Linux commit bde4a5a00e761f55be92f62378cf5024ced79ee3
Some designs implement reset GPIO via a GPIO expander connected to a
peripheral bus. One such example would be i.MX7 Sabre board where said
GPIO is provided by SPI shift register connected to a bitbanged SPI bus.
To support such designs, allow reset GPIO request to defer probing of the
driver.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Cc: yurovsky@gmail.com
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Cc: Dong Aisheng <dongas86@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/pci-imx6.c | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/drivers/pci/pci-imx6.c b/drivers/pci/pci-imx6.c index 6471f95b62..ce68b007ab 100644 --- a/drivers/pci/pci-imx6.c +++ b/drivers/pci/pci-imx6.c @@ -562,8 +562,8 @@ static const struct dw_pcie_host_ops imx6_pcie_host_ops = { .host_init = imx6_pcie_host_init, }; -static int __init imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, - struct device_d *dev) +static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, + struct device_d *dev) { struct dw_pcie *pci = imx6_pcie->pci; struct pcie_port *pp = &pci->pp; @@ -581,7 +581,7 @@ static int __init imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, return 0; } -static int __init imx6_pcie_probe(struct device_d *dev) +static int imx6_pcie_probe(struct device_d *dev) { struct resource *iores; struct dw_pcie *pci; @@ -599,13 +599,11 @@ static int __init imx6_pcie_probe(struct device_d *dev) imx6_pcie->variant = (enum imx6_pcie_variants)of_device_get_match_data(dev); - iores = dev_request_mem_resource(dev, 0); - if (IS_ERR(iores)) - return PTR_ERR(iores); - pci->dbi_base = IOMEM(iores->start); - /* Fetch GPIOs */ imx6_pcie->reset_gpio = of_get_named_gpio(np, "reset-gpio", 0); + if (imx6_pcie->reset_gpio == -EPROBE_DEFER) + return imx6_pcie->reset_gpio; + if (gpio_is_valid(imx6_pcie->reset_gpio)) { ret = gpio_request_one(imx6_pcie->reset_gpio, GPIOF_OUT_INIT_LOW, "PCIe reset"); @@ -615,6 +613,11 @@ static int __init imx6_pcie_probe(struct device_d *dev) } } + iores = dev_request_mem_resource(dev, 0); + if (IS_ERR(iores)) + return PTR_ERR(iores); + pci->dbi_base = IOMEM(iores->start); + /* Fetch clocks */ imx6_pcie->pcie_phy = clk_get(dev, "pcie_phy"); if (IS_ERR(imx6_pcie->pcie_phy)) { |