[PATCH v7 3/8] PCI/VGA: Tidy up the code and comment format
From: Sui Jingfeng
Date: Mon Jun 12 2023 - 23:04:35 EST
From: Sui Jingfeng <suijingfeng@xxxxxxxxxxx>
This patch replaces the leading space with a tab and removes the double
blank line, no functional change.
Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Cc: Maxime Ripard <mripard@xxxxxxxxxx>
Cc: Thomas Zimmermann <tzimmermann@xxxxxxx>
Cc: David Airlie <airlied@xxxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Signed-off-by: Sui Jingfeng <suijingfeng@xxxxxxxxxxx>
Reviewed-by: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx>
---
drivers/pci/vgaarb.c | 108 ++++++++++++++++++++++++-----------------
include/linux/vgaarb.h | 4 +-
2 files changed, 65 insertions(+), 47 deletions(-)
diff --git a/drivers/pci/vgaarb.c b/drivers/pci/vgaarb.c
index 22a505e877dc..ceb914245383 100644
--- a/drivers/pci/vgaarb.c
+++ b/drivers/pci/vgaarb.c
@@ -61,7 +61,6 @@ static bool vga_arbiter_used;
static DEFINE_SPINLOCK(vga_lock);
static DECLARE_WAIT_QUEUE_HEAD(vga_wait_queue);
-
static const char *vga_iostate_to_str(unsigned int iostate)
{
/* Ignore VGA_RSRC_IO and VGA_RSRC_MEM */
@@ -79,8 +78,10 @@ static const char *vga_iostate_to_str(unsigned int iostate)
static int vga_str_to_iostate(char *buf, int str_size, unsigned int *io_state)
{
- /* we could in theory hand out locks on IO and mem
- * separately to userspace but it can cause deadlocks */
+ /*
+ * We could in theory hand out locks on IO and mem
+ * separately to userspace but it can cause deadlocks
+ */
if (strncmp(buf, "none", 4) == 0) {
*io_state = VGA_RSRC_NONE;
return 1;
@@ -99,7 +100,7 @@ static int vga_str_to_iostate(char *buf, int str_size, unsigned int *io_state)
return 1;
}
-/* this is only used a cookie - it should not be dereferenced */
+/* This is only used as cookie, it should not be dereferenced */
static struct pci_dev *vga_default;
/* Find somebody in our list */
@@ -193,14 +194,17 @@ int vga_remove_vgacon(struct pci_dev *pdev)
#endif
EXPORT_SYMBOL(vga_remove_vgacon);
-/* If we don't ever use VGA arb we should avoid
- turning off anything anywhere due to old X servers getting
- confused about the boot device not being VGA */
+/*
+ * If we don't ever use VGA arb we should avoid
+ * turning off anything anywhere due to old X servers getting
+ * confused about the boot device not being VGA
+ */
static void vga_check_first_use(void)
{
- /* we should inform all GPUs in the system that
- * VGA arb has occurred and to try and disable resources
- * if they can */
+ /*
+ * We should inform all GPUs in the system that
+ * vgaarb has occurred and to try and disable resources if they can
+ */
if (!vga_arbiter_used) {
vga_arbiter_used = true;
vga_arbiter_notify_clients();
@@ -216,7 +220,8 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
unsigned int pci_bits;
u32 flags = 0;
- /* Account for "normal" resources to lock. If we decode the legacy,
+ /*
+ * Account for "normal" resources to lock. If we decode the legacy,
* counterpart, we need to request it as well
*/
if ((rsrc & VGA_RSRC_NORMAL_IO) &&
@@ -236,7 +241,8 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
if (wants == 0)
goto lock_them;
- /* We don't need to request a legacy resource, we just enable
+ /*
+ * We don't need to request a legacy resource, we just enable
* appropriate decoding and go
*/
legacy_wants = wants & VGA_RSRC_LEGACY_MASK;
@@ -252,7 +258,8 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
if (vgadev == conflict)
continue;
- /* We have a possible conflict. before we go further, we must
+ /*
+ * We have a possible conflict. before we go further, we must
* check if we sit on the same bus as the conflicting device.
* if we don't, then we must tie both IO and MEM resources
* together since there is only a single bit controlling
@@ -263,13 +270,15 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
lwants = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM;
}
- /* Check if the guy has a lock on the resource. If he does,
+ /*
+ * Check if the guy has a lock on the resource. If he does,
* return the conflicting entry
*/
if (conflict->locks & lwants)
return conflict;
- /* Ok, now check if it owns the resource we want. We can
+ /*
+ * Ok, now check if it owns the resource we want. We can
* lock resources that are not decoded, therefore a device
* can own resources it doesn't decode.
*/
@@ -277,14 +286,16 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
if (!match)
continue;
- /* looks like he doesn't have a lock, we can steal
+ /*
+ * Looks like he doesn't have a lock, we can steal
* them from him
*/
flags = 0;
pci_bits = 0;
- /* If we can't control legacy resources via the bridge, we
+ /*
+ * If we can't control legacy resources via the bridge, we
* also need to disable normal decoding.
*/
if (!conflict->bridge_has_one_vga) {
@@ -311,7 +322,8 @@ static struct vga_device *__vga_tryget(struct vga_device *vgadev,
}
enable_them:
- /* ok dude, we got it, everybody conflicting has been disabled, let's
+ /*
+ * Ok dude, we got it, everybody conflicting has been disabled, let's
* enable us. Mark any bits in "owns" regardless of whether we
* decoded them. We can lock resources we don't decode, therefore
* we must track them via "owns".
@@ -353,7 +365,8 @@ static void __vga_put(struct vga_device *vgadev, unsigned int rsrc)
vgaarb_dbg(dev, "%s\n", __func__);
- /* Update our counters, and account for equivalent legacy resources
+ /*
+ * Update our counters, and account for equivalent legacy resources
* if we decode them
*/
if ((rsrc & VGA_RSRC_NORMAL_IO) && vgadev->io_norm_cnt > 0) {
@@ -371,7 +384,8 @@ static void __vga_put(struct vga_device *vgadev, unsigned int rsrc)
if ((rsrc & VGA_RSRC_LEGACY_MEM) && vgadev->mem_lock_cnt > 0)
vgadev->mem_lock_cnt--;
- /* Just clear lock bits, we do lazy operations so we don't really
+ /*
+ * Just clear lock bits, we do lazy operations so we don't really
* have to bother about anything else at this point
*/
if (vgadev->io_lock_cnt == 0)
@@ -379,7 +393,8 @@ static void __vga_put(struct vga_device *vgadev, unsigned int rsrc)
if (vgadev->mem_lock_cnt == 0)
vgadev->locks &= ~VGA_RSRC_LEGACY_MEM;
- /* Kick the wait queue in case somebody was waiting if we actually
+ /*
+ * Kick the wait queue in case somebody was waiting if we actually
* released something
*/
if (old_locks != vgadev->locks)
@@ -447,8 +462,8 @@ int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible)
if (conflict == NULL)
break;
-
- /* We have a conflict, we wait until somebody kicks the
+ /*
+ * We have a conflict, we wait until somebody kicks the
* work queue. Currently we have one work queue that we
* kick each time some resources are released, but it would
* be fairly easy to have a per device one so that we only
@@ -665,7 +680,7 @@ static bool vga_is_boot_device(struct vga_device *vgadev)
}
/*
- * vgadev has neither IO nor MEM enabled. If we haven't found any
+ * Vgadev has neither IO nor MEM enabled. If we haven't found any
* other VGA devices, it is the best candidate so far.
*/
if (!boot_vga)
@@ -706,7 +721,7 @@ static void vga_arbiter_check_bridge_sharing(struct vga_device *vgadev)
bus = same_bridge_vgadev->pdev->bus;
bridge = bus->self;
- /* see if the share a bridge with this device */
+ /* See if the share a bridge with this device */
if (new_bridge == bridge) {
/*
* If their direct parent bridge is the same
@@ -777,9 +792,10 @@ static bool vga_arbiter_add_pci_device(struct pci_dev *pdev)
vgadev->decodes = VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM |
VGA_RSRC_NORMAL_IO | VGA_RSRC_NORMAL_MEM;
- /* by default mark it as decoding */
+ /* By default, mark it as decoding */
vga_decode_count++;
- /* Mark that we "own" resources based on our enables, we will
+ /*
+ * Mark that we "own" resources based on our enables, we will
* clear that below if the bridge isn't forwarding
*/
pci_read_config_word(pdev, PCI_COMMAND, &cmd);
@@ -860,7 +876,7 @@ static bool vga_arbiter_del_pci_device(struct pci_dev *pdev)
return ret;
}
-/* this is called with the lock */
+/* This is called with the lock */
static inline void vga_update_device_decodes(struct vga_device *vgadev,
int new_decodes)
{
@@ -877,7 +893,7 @@ static inline void vga_update_device_decodes(struct vga_device *vgadev,
vga_iostate_to_str(vgadev->decodes),
vga_iostate_to_str(vgadev->owns));
- /* if we removed locked decodes, lock count goes to zero, and release */
+ /* If we removed locked decodes, lock count goes to zero, and release */
if (decodes_unlocked) {
if (decodes_unlocked & VGA_RSRC_LEGACY_IO)
vgadev->io_lock_cnt = 0;
@@ -886,7 +902,7 @@ static inline void vga_update_device_decodes(struct vga_device *vgadev,
__vga_put(vgadev, decodes_unlocked);
}
- /* change decodes counter */
+ /* Change decodes counter */
if (old_decodes & VGA_RSRC_LEGACY_MASK &&
!(new_decodes & VGA_RSRC_LEGACY_MASK))
vga_decode_count--;
@@ -910,14 +926,15 @@ static void __vga_set_legacy_decoding(struct pci_dev *pdev,
if (vgadev == NULL)
goto bail;
- /* don't let userspace futz with kernel driver decodes */
+ /* Don't let userspace futz with kernel driver decodes */
if (userspace && vgadev->set_decode)
goto bail;
- /* update the device decodes + counter */
+ /* Update the device decodes + counter */
vga_update_device_decodes(vgadev, decodes);
- /* XXX if somebody is going from "doesn't decode" to "decodes" state
+ /*
+ * XXX if somebody is going from "doesn't decode" to "decodes" state
* here, additional care must be taken as we may have pending owner
* ship of non-legacy region ...
*/
@@ -952,9 +969,9 @@ EXPORT_SYMBOL(vga_set_legacy_decoding);
* @set_decode callback: If a client can disable its GPU VGA resource, it
* will get a callback from this to set the encode/decode state.
*
- * Rationale: we cannot disable VGA decode resources unconditionally some single
- * GPU laptops seem to require ACPI or BIOS access to the VGA registers to
- * control things like backlights etc. Hopefully newer multi-GPU laptops do
+ * Rationale: we cannot disable VGA decode resources unconditionally, some
+ * single GPU laptops seem to require ACPI or BIOS access to the VGA registers
+ * to control things like backlights etc. Hopefully newer multi-GPU laptops do
* something saner, and desktops won't have any special ACPI for this. The
* driver will get a callback when VGA arbitration is first used by userspace
* since some older X servers have issues.
@@ -984,7 +1001,6 @@ int vga_client_register(struct pci_dev *pdev,
bail:
spin_unlock_irqrestore(&vga_lock, flags);
return ret;
-
}
EXPORT_SYMBOL(vga_client_register);
@@ -1075,7 +1091,6 @@ static int vga_pci_str_to_vars(char *buf, int count, unsigned int *domain,
int n;
unsigned int slot, func;
-
n = sscanf(buf, "PCI:%x:%x:%x.%x", domain, bus, &slot, &func);
if (n != 4)
return 0;
@@ -1310,7 +1325,7 @@ static ssize_t vga_arb_write(struct file *file, const char __user *buf,
curr_pos += 7;
remaining -= 7;
pr_debug("client 0x%p called 'target'\n", priv);
- /* if target is default */
+ /* If target is default */
if (!strncmp(curr_pos, "default", 7))
pdev = pci_dev_get(vga_default_device());
else {
@@ -1427,7 +1442,6 @@ static int vga_arb_open(struct inode *inode, struct file *file)
priv->cards[0].io_cnt = 0;
priv->cards[0].mem_cnt = 0;
-
return 0;
}
@@ -1461,7 +1475,7 @@ static int vga_arb_release(struct inode *inode, struct file *file)
}
/*
- * callback any registered clients to let them know we have a
+ * Callback any registered clients to let them know we have a
* change in VGA cards
*/
static void vga_arbiter_notify_clients(void)
@@ -1500,9 +1514,11 @@ static int pci_notify(struct notifier_block *nb, unsigned long action,
if (pdev->class != PCI_CLASS_DISPLAY_VGA << 8)
return 0;
- /* For now we're only intereted in devices added and removed. I didn't
+ /*
+ * For now we're only intereted in devices added and removed. I didn't
* test this thing here, so someone needs to double check for the
- * cases of hotplugable vga cards. */
+ * cases of hotplugable vga cards.
+ */
if (action == BUS_NOTIFY_ADD_DEVICE)
notify = vga_arbiter_add_pci_device(pdev);
else if (action == BUS_NOTIFY_DEL_DEVICE)
@@ -1543,8 +1559,10 @@ static int __init vga_arb_device_init(void)
bus_register_notifier(&pci_bus_type, &pci_notifier);
- /* We add all PCI devices satisfying VGA class in the arbiter by
- * default */
+ /*
+ * We add all PCI devices satisfying VGA class in the arbiter by
+ * default
+ */
while (1) {
pdev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, pdev);
if (!pdev)
diff --git a/include/linux/vgaarb.h b/include/linux/vgaarb.h
index b4b9137f9792..6d5465f8c3f2 100644
--- a/include/linux/vgaarb.h
+++ b/include/linux/vgaarb.h
@@ -96,7 +96,7 @@ static inline int vga_client_register(struct pci_dev *pdev,
static inline int vga_get_interruptible(struct pci_dev *pdev,
unsigned int rsrc)
{
- return vga_get(pdev, rsrc, 1);
+ return vga_get(pdev, rsrc, 1);
}
/**
@@ -111,7 +111,7 @@ static inline int vga_get_interruptible(struct pci_dev *pdev,
static inline int vga_get_uninterruptible(struct pci_dev *pdev,
unsigned int rsrc)
{
- return vga_get(pdev, rsrc, 0);
+ return vga_get(pdev, rsrc, 0);
}
static inline void vga_client_unregister(struct pci_dev *pdev)
--
2.25.1