diff options
| author | Richard Zhu <hongxing.zhu@nxp.com> | 2017-05-26 09:10:42 +0800 |
|---|---|---|
| committer | Leonard Crestez <leonard.crestez@nxp.com> | 2018-08-24 12:41:33 +0300 |
| commit | 348e11d6b972e0e244cf425119d30ff67bba11c7 (patch) | |
| tree | 89f00af134d6bfb1b70d94b2c94a0d3a7a8eb83c /drivers/pci/host/pci-imx6.c | |
| parent | 1698446b4d7e9d1a365c54d541ee96c03eb39876 (diff) | |
PCI: imx6: Allow probe deferral by reset GPIO
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
(cherry picked from commit bde4a5a00e761f55be92f62378cf5024ced79ee3)
Diffstat (limited to 'drivers/pci/host/pci-imx6.c')
| -rw-r--r-- | drivers/pci/host/pci-imx6.c | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c index bbd3a286673b..250952e7691e 100644 --- a/drivers/pci/host/pci-imx6.c +++ b/drivers/pci/host/pci-imx6.c @@ -807,7 +807,7 @@ static struct 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, +static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie, struct platform_device *pdev) { struct pcie_port *pp = &imx6_pcie->pp; @@ -1181,7 +1181,7 @@ static const struct dev_pm_ops pci_imx_pm_ops = { }; #endif -static int __init imx6_pcie_probe(struct platform_device *pdev) +static int imx6_pcie_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct imx6_pcie *imx6_pcie; @@ -1208,10 +1208,6 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) return -EINVAL; } - /* Added for PCI abort handling */ - hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0, - "imprecise external abort"); - np = of_find_compatible_node(NULL, NULL, "fsl,imx-pcie-phy"); if (np != NULL) { @@ -1262,6 +1258,8 @@ static int __init imx6_pcie_probe(struct platform_device *pdev) dev_err(dev, "unable to get reset gpio\n"); return ret; } + } else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) { + return imx6_pcie->reset_gpio; } /* Fetch clocks */ @@ -1572,11 +1570,22 @@ static struct platform_driver imx6_pcie_driver = { .of_match_table = imx6_pcie_of_match, .pm = &pci_imx_pm_ops, }, + .probe = imx6_pcie_probe, .shutdown = imx6_pcie_shutdown, }; static int __init imx6_pcie_init(void) { - return platform_driver_probe(&imx6_pcie_driver, imx6_pcie_probe); + /* + * Since probe() can be deferred we need to make sure that + * hook_fault_code is not called after __init memory is freed + * by kernel and since imx6q_pcie_abort_handler() is a no-op, + * we can install the handler here without risking it + * accessing some uninitialized driver state. + */ + hook_fault_code(16 + 6, imx6q_pcie_abort_handler, SIGBUS, 0, + "imprecise external abort"); + + return platform_driver_register(&imx6_pcie_driver); } device_initcall(imx6_pcie_init); |