a5f40e8098
Many PCI host controller drivers aren't prepared to have their devices unbound from them forcefully (e.g., through /sys/.../<driver>/unbind), as they don't provide any driver .remove callback, where they'd detach the root bus, release resources, etc. Keeping the driver built in (i.e., not a loadable module) is not enough; and providing no .remove callback just means we don't do any teardown. To rule out the possibility of unbinding a device via sysfs, we need to set the ".suppress_bind_attrs" field. I found the suspect drivers via the following search: git grep -l platform_driver $(git grep -L -e '\.remove' -e suppress_bind_attrs drivers/pci/) Then I inspected them to ensure that (a) they set up a PCI bus in their probe() and (b) they don't have a remove() callback for undoing the setup Suggested-by: Bjorn Helgaas <helgaas@kernel.org> Signed-off-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
68 lines
1.9 KiB
C
68 lines
1.9 KiB
C
/*
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* Simple, generic PCI host controller driver targetting firmware-initialised
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* systems and virtual machines (e.g. the PCI emulation provided by kvmtool).
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*
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* Copyright (C) 2014 ARM Limited
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*
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* Author: Will Deacon <will.deacon@arm.com>
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*/
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/of_address.h>
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#include <linux/of_pci.h>
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#include <linux/pci-ecam.h>
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#include <linux/platform_device.h>
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static struct pci_ecam_ops gen_pci_cfg_cam_bus_ops = {
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.bus_shift = 16,
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.pci_ops = {
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.map_bus = pci_ecam_map_bus,
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.read = pci_generic_config_read,
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.write = pci_generic_config_write,
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}
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};
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static const struct of_device_id gen_pci_of_match[] = {
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{ .compatible = "pci-host-cam-generic",
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.data = &gen_pci_cfg_cam_bus_ops },
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{ .compatible = "pci-host-ecam-generic",
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.data = &pci_generic_ecam_ops },
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{ },
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};
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static int gen_pci_probe(struct platform_device *pdev)
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{
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const struct of_device_id *of_id;
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struct pci_ecam_ops *ops;
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of_id = of_match_node(gen_pci_of_match, pdev->dev.of_node);
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ops = (struct pci_ecam_ops *)of_id->data;
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return pci_host_common_probe(pdev, ops);
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}
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static struct platform_driver gen_pci_driver = {
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.driver = {
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.name = "pci-host-generic",
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.of_match_table = gen_pci_of_match,
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.suppress_bind_attrs = true,
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},
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.probe = gen_pci_probe,
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};
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builtin_platform_driver(gen_pci_driver);
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