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authorLinus Torvalds <torvalds@linux-foundation.org>2012-01-11 21:50:26 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2012-01-11 21:50:26 -0500
commit7b67e751479d50b7f84d1a3cc5216eed5e534b66 (patch)
treea1a6746857cf65f04dde739fe271bf4143d55eaf /drivers/uio
parent9f13a1fd452f11c18004ba2422a6384b424ec8a9 (diff)
parent76ccc297018d25d55b789bbd508861ef1e2cdb0c (diff)
Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci: (80 commits) x86/PCI: Expand the x86_msi_ops to have a restore MSIs. PCI: Increase resource array mask bit size in pcim_iomap_regions() PCI: DEVICE_COUNT_RESOURCE should be equal to PCI_NUM_RESOURCES PCI: pci_ids: add device ids for STA2X11 device (aka ConneXT) PNP: work around Dell 1536/1546 BIOS MMCONFIG bug that breaks USB x86/PCI: amd: factor out MMCONFIG discovery PCI: Enable ATS at the device state restore PCI: msi: fix imbalanced refcount of msi irq sysfs objects PCI: kconfig: English typo in pci/pcie/Kconfig PCI/PM/Runtime: make PCI traces quieter PCI: remove pci_create_bus() xtensa/PCI: convert to pci_scan_root_bus() for correct root bus resources x86/PCI: convert to pci_create_root_bus() and pci_scan_root_bus() x86/PCI: use pci_scan_bus() instead of pci_scan_bus_parented() x86/PCI: read Broadcom CNB20LE host bridge info before PCI scan sparc32, leon/PCI: convert to pci_scan_root_bus() for correct root bus resources sparc/PCI: convert to pci_create_root_bus() sh/PCI: convert to pci_scan_root_bus() for correct root bus resources powerpc/PCI: convert to pci_create_root_bus() powerpc/PCI: split PHB part out of pcibios_map_io_space() ... Fix up conflicts in drivers/pci/msi.c and include/linux/pci_regs.h due to the same patches being applied in other branches.
Diffstat (limited to 'drivers/uio')
-rw-r--r--drivers/uio/uio_pci_generic.c78
1 files changed, 7 insertions, 71 deletions
diff --git a/drivers/uio/uio_pci_generic.c b/drivers/uio/uio_pci_generic.c
index 02bd47bdee1c..0bd08ef2b394 100644
--- a/drivers/uio/uio_pci_generic.c
+++ b/drivers/uio/uio_pci_generic.c
@@ -45,77 +45,12 @@ to_uio_pci_generic_dev(struct uio_info *info)
45static irqreturn_t irqhandler(int irq, struct uio_info *info) 45static irqreturn_t irqhandler(int irq, struct uio_info *info)
46{ 46{
47 struct uio_pci_generic_dev *gdev = to_uio_pci_generic_dev(info); 47 struct uio_pci_generic_dev *gdev = to_uio_pci_generic_dev(info);
48 struct pci_dev *pdev = gdev->pdev;
49 irqreturn_t ret = IRQ_NONE;
50 u32 cmd_status_dword;
51 u16 origcmd, newcmd, status;
52
53 /* We do a single dword read to retrieve both command and status.
54 * Document assumptions that make this possible. */
55 BUILD_BUG_ON(PCI_COMMAND % 4);
56 BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
57
58 pci_block_user_cfg_access(pdev);
59
60 /* Read both command and status registers in a single 32-bit operation.
61 * Note: we could cache the value for command and move the status read
62 * out of the lock if there was a way to get notified of user changes
63 * to command register through sysfs. Should be good for shared irqs. */
64 pci_read_config_dword(pdev, PCI_COMMAND, &cmd_status_dword);
65 origcmd = cmd_status_dword;
66 status = cmd_status_dword >> 16;
67
68 /* Check interrupt status register to see whether our device
69 * triggered the interrupt. */
70 if (!(status & PCI_STATUS_INTERRUPT))
71 goto done;
72
73 /* We triggered the interrupt, disable it. */
74 newcmd = origcmd | PCI_COMMAND_INTX_DISABLE;
75 if (newcmd != origcmd)
76 pci_write_config_word(pdev, PCI_COMMAND, newcmd);
77 48
78 /* UIO core will signal the user process. */ 49 if (!pci_check_and_mask_intx(gdev->pdev))
79 ret = IRQ_HANDLED; 50 return IRQ_NONE;
80done:
81
82 pci_unblock_user_cfg_access(pdev);
83 return ret;
84}
85 51
86/* Verify that the device supports Interrupt Disable bit in command register, 52 /* UIO core will signal the user process. */
87 * per PCI 2.3, by flipping this bit and reading it back: this bit was readonly 53 return IRQ_HANDLED;
88 * in PCI 2.2. */
89static int __devinit verify_pci_2_3(struct pci_dev *pdev)
90{
91 u16 orig, new;
92 int err = 0;
93
94 pci_block_user_cfg_access(pdev);
95 pci_read_config_word(pdev, PCI_COMMAND, &orig);
96 pci_write_config_word(pdev, PCI_COMMAND,
97 orig ^ PCI_COMMAND_INTX_DISABLE);
98 pci_read_config_word(pdev, PCI_COMMAND, &new);
99 /* There's no way to protect against
100 * hardware bugs or detect them reliably, but as long as we know
101 * what the value should be, let's go ahead and check it. */
102 if ((new ^ orig) & ~PCI_COMMAND_INTX_DISABLE) {
103 err = -EBUSY;
104 dev_err(&pdev->dev, "Command changed from 0x%x to 0x%x: "
105 "driver or HW bug?\n", orig, new);
106 goto err;
107 }
108 if (!((new ^ orig) & PCI_COMMAND_INTX_DISABLE)) {
109 dev_warn(&pdev->dev, "Device does not support "
110 "disabling interrupts: unable to bind.\n");
111 err = -ENODEV;
112 goto err;
113 }
114 /* Now restore the original value. */
115 pci_write_config_word(pdev, PCI_COMMAND, orig);
116err:
117 pci_unblock_user_cfg_access(pdev);
118 return err;
119} 54}
120 55
121static int __devinit probe(struct pci_dev *pdev, 56static int __devinit probe(struct pci_dev *pdev,
@@ -138,9 +73,10 @@ static int __devinit probe(struct pci_dev *pdev,
138 return -ENODEV; 73 return -ENODEV;
139 } 74 }
140 75
141 err = verify_pci_2_3(pdev); 76 if (!pci_intx_mask_supported(pdev)) {
142 if (err) 77 err = -ENODEV;
143 goto err_verify; 78 goto err_verify;
79 }
144 80
145 gdev = kzalloc(sizeof(struct uio_pci_generic_dev), GFP_KERNEL); 81 gdev = kzalloc(sizeof(struct uio_pci_generic_dev), GFP_KERNEL);
146 if (!gdev) { 82 if (!gdev) {