From b3c32c4f9565f93407921c0d8a4458042eb8998e Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Thu, 25 Oct 2012 09:36:03 +0800 Subject: PCI/PM: Fix proc config reg access for D3cold and bridge suspending In https://bugzilla.kernel.org/show_bug.cgi?id=48981 Peter reported that /proc/bus/pci/??/??.? does not work for 3.6. This is because the device configuration space registers are not accessible if the corresponding parent bridge is suspended or the device is put into D3cold state. This is the same as /sys/bus/pci/devices/0000:??:??.?/config access issue. So the function used to solve sysfs issue is used to solve this issue. This patch moves pci_config_pm_runtime_get()/_put() from pci/pci-sysfs.c to pci/pci.c and makes them extern so they can be used by both the sysfs and proc paths. [bhelgaas: changelog, references, reporters] Reference: https://bugzilla.kernel.org/show_bug.cgi?id=48981 Reference: https://bugzilla.kernel.org/show_bug.cgi?id=49031 Reported-by: Forrest Loomis Reported-by: Peter Reported-by: Micael Dias Signed-off-by: Huang Ying Signed-off-by: Bjorn Helgaas Acked-by: Rafael J. Wysocki CC: stable@vger.kernel.org # v3.6+ --- drivers/pci/proc.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'drivers/pci/proc.c') diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c index eb907a8faf2a..9b8505ccc56d 100644 --- a/drivers/pci/proc.c +++ b/drivers/pci/proc.c @@ -76,6 +76,8 @@ proc_bus_pci_read(struct file *file, char __user *buf, size_t nbytes, loff_t *pp if (!access_ok(VERIFY_WRITE, buf, cnt)) return -EINVAL; + pci_config_pm_runtime_get(dev); + if ((pos & 1) && cnt) { unsigned char val; pci_user_read_config_byte(dev, pos, &val); @@ -121,6 +123,8 @@ proc_bus_pci_read(struct file *file, char __user *buf, size_t nbytes, loff_t *pp cnt--; } + pci_config_pm_runtime_put(dev); + *ppos = pos; return nbytes; } @@ -146,6 +150,8 @@ proc_bus_pci_write(struct file *file, const char __user *buf, size_t nbytes, lof if (!access_ok(VERIFY_READ, buf, cnt)) return -EINVAL; + pci_config_pm_runtime_get(dev); + if ((pos & 1) && cnt) { unsigned char val; __get_user(val, buf); @@ -191,6 +197,8 @@ proc_bus_pci_write(struct file *file, const char __user *buf, size_t nbytes, lof cnt--; } + pci_config_pm_runtime_put(dev); + *ppos = pos; i_size_write(ino, dp->size); return nbytes; -- cgit v1.2.1