Re: [PATCH 3/5 v4] usb: pci-quirks: Protect the I/O port pair of SB800

From: Boszormenyi Zoltan
Date: Fri Jul 14 2017 - 04:35:32 EST


2017-06-22 15:21 keltezÃssel, ZoltÃn BÃszÃrmÃnyi Ãrta:
This patch uses the previously introduced macro called
request_declared_muxed_region() to synchronize access to
the I/O port pair 0xcd6 / 0xcd7 on SB800.

These I/O ports are also used by i2c-piix4 and sp5100_tco,
so synchronization is necessary. The other drivers will also
be modified to use the new macro in subsequest patched.

v1: Started with a common mutex in a C source file.

v2: Declared the common mutex in drivers/usb/host/pci-quirks.c
instead of in a common C file.

v3: Switched to using the new request_declared_muxed_region
macro.

v4: Fixed checkpatch.pl warnings and use the new
release_declared_region() macro.

Signed-off-by: ZoltÃn BÃszÃrmÃnyi <zboszor@xxxxx>
---
drivers/usb/host/pci-quirks.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index a9a1e4c..593942a 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -279,6 +279,8 @@ bool usb_amd_prefetch_quirk(void)
}
EXPORT_SYMBOL_GPL(usb_amd_prefetch_quirk);
+static struct resource sb800_res = DEFINE_RES_IO_NAMED(0xcd6, 2, "SB800 USB");
+
/*
* The hardware normally enables the A-link power management feature, which
* lets the system lower the power consumption in idle states.
@@ -314,11 +316,13 @@ static void usb_amd_quirk_pll(int disable)
if (amd_chipset.sb_type.gen == AMD_CHIPSET_SB800 ||
amd_chipset.sb_type.gen == AMD_CHIPSET_HUDSON2 ||
amd_chipset.sb_type.gen == AMD_CHIPSET_BOLTON) {
+ request_declared_muxed_region(&sb800_res);
outb_p(AB_REG_BAR_LOW, 0xcd6);
addr_low = inb_p(0xcd7);
outb_p(AB_REG_BAR_HIGH, 0xcd6);
addr_high = inb_p(0xcd7);
addr = addr_high << 8 | addr_low;
+ release_declared_region(&sb800_res);
outl_p(0x30, AB_INDX(addr));
outl_p(0x40, AB_DATA(addr));