[PATCH AUTOSEL 4.20 031/117] fpga: altera-cvp: fix probing for multiple FPGAs on the bus

From: Sasha Levin
Date: Tue Jan 08 2019 - 15:08:28 EST


From: Anatolij Gustschin <agust@xxxxxxx>

[ Upstream commit 30522a951f9d02f261d0697c35cb42205b1fae17 ]

Currently registering CvP managers works only for first probed CvP
device, for all other devices it is refused due to duplicated chkcfg
sysfs entry:

fpga_manager fpga3: Altera CvP FPGA Manager @0000:0c:00.0 registered
sysfs: cannot create duplicate filename '/bus/pci/drivers/altera-cvp/chkcfg'
CPU: 0 PID: 3808 Comm: bash Tainted: G O 4.19.0-custom+ #5
Call Trace:
dump_stack+0x46/0x5b
sysfs_warn_dup+0x53/0x60
sysfs_add_file_mode_ns+0x16d/0x180
sysfs_create_file_ns+0x51/0x60
altera_cvp_probe+0x16f/0x2a0 [altera_cvp]
local_pci_probe+0x3f/0xa0
? pci_match_device+0xb1/0xf0
pci_device_probe+0x116/0x170
really_probe+0x21b/0x2c0
driver_probe_device+0x4b/0xe0
bind_store+0xcb/0x130
kernfs_fop_write+0xfd/0x180
__vfs_write+0x21/0x150
? selinux_file_permission+0xdc/0x130
vfs_write+0xa8/0x1a0
? find_vma+0xd/0x60
ksys_write+0x3d/0x90
do_syscall_64+0x44/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
...
altera-cvp 0000:0c:00.0: Can't create sysfs chkcfg file
fpga_manager fpga3: fpga_mgr_unregister Altera CvP FPGA Manager @0000:0c:00.0

Move chkcfg creation to module init as suggested by Alan.

Signed-off-by: Anatolij Gustschin <agust@xxxxxxx>
Acked-by: Alan Tull <atull@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/fpga/altera-cvp.c | 34 ++++++++++++++++++++++++----------
1 file changed, 24 insertions(+), 10 deletions(-)

diff --git a/drivers/fpga/altera-cvp.c b/drivers/fpga/altera-cvp.c
index 610a1558e0ed..d9fa7d4bf11f 100644
--- a/drivers/fpga/altera-cvp.c
+++ b/drivers/fpga/altera-cvp.c
@@ -466,14 +466,6 @@ static int altera_cvp_probe(struct pci_dev *pdev,
if (ret)
goto err_unmap;

- ret = driver_create_file(&altera_cvp_driver.driver,
- &driver_attr_chkcfg);
- if (ret) {
- dev_err(&pdev->dev, "Can't create sysfs chkcfg file\n");
- fpga_mgr_unregister(mgr);
- goto err_unmap;
- }
-
return 0;

err_unmap:
@@ -491,7 +483,6 @@ static void altera_cvp_remove(struct pci_dev *pdev)
struct altera_cvp_conf *conf = mgr->priv;
u16 cmd;

- driver_remove_file(&altera_cvp_driver.driver, &driver_attr_chkcfg);
fpga_mgr_unregister(mgr);
pci_iounmap(pdev, conf->map);
pci_release_region(pdev, CVP_BAR);
@@ -500,7 +491,30 @@ static void altera_cvp_remove(struct pci_dev *pdev)
pci_write_config_word(pdev, PCI_COMMAND, cmd);
}

-module_pci_driver(altera_cvp_driver);
+static int __init altera_cvp_init(void)
+{
+ int ret;
+
+ ret = pci_register_driver(&altera_cvp_driver);
+ if (ret)
+ return ret;
+
+ ret = driver_create_file(&altera_cvp_driver.driver,
+ &driver_attr_chkcfg);
+ if (ret)
+ pr_warn("Can't create sysfs chkcfg file\n");
+
+ return 0;
+}
+
+static void __exit altera_cvp_exit(void)
+{
+ driver_remove_file(&altera_cvp_driver.driver, &driver_attr_chkcfg);
+ pci_unregister_driver(&altera_cvp_driver);
+}
+
+module_init(altera_cvp_init);
+module_exit(altera_cvp_exit);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Anatolij Gustschin <agust@xxxxxxx>");
--
2.19.1