[PATCH 2.6.16-mm1 1/4] PCI legacy I/O port free driver (take 6) -Changes to generic PCI code

From: Kenji Kaneshige
Date: Fri Mar 24 2006 - 00:36:15 EST


This patch adds the following changes into generic PCI code especially
for PCI legacy free drivers.

- Moved the following two things from pci_enable_device() into
pci_enable_device_bars(). By this change, we can use
pci_enable_device_bars() to enable only the specific regions.

o Call pci_fixup_device() on the device
o Set dev->is_enabled

- Added new field 'bars_enabled' into struct pci_device to
remember which BARs already enabled. This new field is
initialized at pci_enable_device_bars() time and cleared
at pci_disable_device() time.

- Changed pci_request_regions()/pci_release_regions() to
request/release only the regions which have already been
enabled.

- Added helper routine pci_select_bars() which makes proper mask
of BARs from the specified resource type. This would be very
helpful for users of pci_enable_device_bars().

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@xxxxxxxxxxxxxx>

---
drivers/pci/pci-driver.c | 3 ++-
drivers/pci/pci.c | 30 +++++++++++++++++++++++-------
include/linux/pci.h | 12 ++++++++++++
3 files changed, 37 insertions(+), 8 deletions(-)

Index: linux-2.6.16-mm1/drivers/pci/pci-driver.c
===================================================================
--- linux-2.6.16-mm1.orig/drivers/pci/pci-driver.c 2006-03-23 20:04:06.000000000 +0900
+++ linux-2.6.16-mm1/drivers/pci/pci-driver.c 2006-03-23 20:04:11.000000000 +0900
@@ -293,7 +293,8 @@
pci_restore_state(pci_dev);
/* if the device was enabled before suspend, reenable */
if (pci_dev->is_enabled)
- retval = pci_enable_device(pci_dev);
+ retval = pci_enable_device_bars(pci_dev,
+ pci_dev->bars_enabled);
/* if the device was busmaster before the suspend, make it busmaster again */
if (pci_dev->is_busmaster)
pci_set_master(pci_dev);
Index: linux-2.6.16-mm1/drivers/pci/pci.c
===================================================================
--- linux-2.6.16-mm1.orig/drivers/pci/pci.c 2006-03-23 20:04:06.000000000 +0900
+++ linux-2.6.16-mm1/drivers/pci/pci.c 2006-03-23 20:04:11.000000000 +0900
@@ -493,6 +493,9 @@
err = pcibios_enable_device(dev, bars);
if (err < 0)
return err;
+ pci_fixup_device(pci_fixup_enable, dev);
+ dev->is_enabled = 1;
+ dev->bars_enabled = bars;
return 0;
}

@@ -510,8 +513,6 @@
int err = pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
if (err)
return err;
- pci_fixup_device(pci_fixup_enable, dev);
- dev->is_enabled = 1;
return 0;
}

@@ -546,6 +547,7 @@

pcibios_disable_device(dev);
dev->is_enabled = 0;
+ dev->bars_enabled = 0;
}

/**
@@ -628,6 +630,12 @@
{
if (pci_resource_len(pdev, bar) == 0)
return;
+ if (!(pdev->bars_enabled & (1 << bar))) {
+ dev_warn(&pdev->dev,
+ "Trying to release region #%d that is not enabled\n",
+ bar + 1);
+ return;
+ }
if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
release_region(pci_resource_start(pdev, bar),
pci_resource_len(pdev, bar));
@@ -654,7 +662,12 @@
{
if (pci_resource_len(pdev, bar) == 0)
return 0;
-
+ if (!(pdev->bars_enabled & (1 << bar))) {
+ dev_warn(&pdev->dev,
+ "Trying to request region #%d that is not enabled\n",
+ bar + 1);
+ goto err_out;
+ }
if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
if (!request_region(pci_resource_start(pdev, bar),
pci_resource_len(pdev, bar), res_name))
@@ -692,7 +705,8 @@
int i;

for (i = 0; i < 6; i++)
- pci_release_region(pdev, i);
+ if (pdev->bars_enabled & (1 << i))
+ pci_release_region(pdev, i);
}

/**
@@ -713,13 +727,15 @@
int i;

for (i = 0; i < 6; i++)
- if(pci_request_region(pdev, i, res_name))
- goto err_out;
+ if (pdev->bars_enabled & (1 << i))
+ if(pci_request_region(pdev, i, res_name))
+ goto err_out;
return 0;

err_out:
while(--i >= 0)
- pci_release_region(pdev, i);
+ if (pdev->bars_enabled & (1 << i))
+ pci_release_region(pdev, i);

return -EBUSY;
}
Index: linux-2.6.16-mm1/include/linux/pci.h
===================================================================
--- linux-2.6.16-mm1.orig/include/linux/pci.h 2006-03-23 20:04:06.000000000 +0900
+++ linux-2.6.16-mm1/include/linux/pci.h 2006-03-23 20:04:11.000000000 +0900
@@ -169,6 +169,7 @@
struct bin_attribute *rom_attr; /* attribute descriptor for sysfs ROM entry */
int rom_attr_enabled; /* has display of the rom attribute been enabled? */
struct bin_attribute *res_attr[DEVICE_COUNT_RESOURCE]; /* sysfs file for resources */
+ int bars_enabled; /* BARs enabled */
};

#define pci_dev_g(n) list_entry(n, struct pci_dev, global_list)
@@ -732,6 +733,17 @@
}
#endif /* HAVE_ARCH_PCI_RESOURCE_TO_USER */

+/*
+ * This helper routine makes bar mask from the type of resource.
+ */
+static inline int pci_select_bars(struct pci_dev *dev, unsigned long flags)
+{
+ int i, bars = 0;
+ for (i = 0; i < PCI_NUM_RESOURCES; i++)
+ if (pci_resource_flags(dev, i) & flags)
+ bars |= (1 << i);
+ return bars;
+}

/*
* The world is not perfect and supplies us with broken PCI devices.

-
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