Decouple BAR reading from pci device init, handle errors gracefully

Pcidev_init() now returns struct pci_device * instead of a BAR stored in
PCI config space. This allows for real error checking instead of having
exit(1) everywhere in pcidev.c.
Thanks to Niklas Söderlund for coming up with the original error
handling patch which was slightly modified and folded into this patch.
Move the declaration of struct pci_device in programmer.h before the
first user.

Corresponding to flashrom svn r1644.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>

1 files changed, 15 insertions, 12 deletions

diff --git a/pcidev.c b/pcidev.c
index f2c8827..c7e9d78 100644
--- a/pcidev.c
+++ b/pcidev.c
@@ -27,7 +27,6 @@
 
 uint32_t io_base_addr;
 struct pci_access *pacc;
-struct pci_dev *pcidev_dev = NULL;
 
 enum pci_bartype {
 	TYPE_MEMBAR,
@@ -156,7 +155,6 @@ uintptr_t pcidev_readbar(struct pci_dev *dev, int bar)
 
 static int pcidev_shutdown(void *data)
 {
-	pcidev_dev = NULL;
 	if (pacc == NULL) {
 		msg_perr("%s: Tried to cleanup an invalid PCI context!\n"
 			 "Please report a bug at flashrom@flashrom.org\n", __func__);
@@ -181,18 +179,24 @@ int pci_init_common(void)
 	return 0;
 }
 
-uintptr_t pcidev_init(int bar, const struct dev_entry *devs)
+/* pcidev_init gets an array of allowed PCI device IDs and returns a pointer to struct pci_dev iff exactly one
+ * match was found. If the "pci=bb:dd.f" programmer parameter was specified, a match is only considered if it
+ * also matches the specified bus:device.function.
+ * For convenience, this function also registers its own undo handlers.
+ */
+struct pci_dev *pcidev_init(const struct dev_entry *devs, int bar)
 {
 	struct pci_dev *dev;
+	struct pci_dev *found_dev = NULL;
 	struct pci_filter filter;
 	char *pcidev_bdf;
 	char *msg = NULL;
 	int found = 0;
 	int i;
-	uintptr_t addr = 0, curaddr = 0;
+	uintptr_t addr = 0;
 
-	if(pci_init_common() != 0)
-		return 1;
+	if (pci_init_common() != 0)
+		return NULL;
 	pci_filter_init(pacc, &filter);
 
 	/* Filter by bb:dd.f (if supplied by the user). */
@@ -200,7 +204,7 @@ uintptr_t pcidev_init(int bar, const struct dev_entry *devs)
 	if (pcidev_bdf != NULL) {
 		if ((msg = pci_filter_parse_slot(&filter, pcidev_bdf))) {
 			msg_perr("Error: %s\n", msg);
-			exit(1);
+			return NULL;
 		}
 	}
 	free(pcidev_bdf);
@@ -230,8 +234,7 @@ uintptr_t pcidev_init(int bar, const struct dev_entry *devs)
 			 * just those with a valid BAR.
 			 */
 			if ((addr = pcidev_readbar(dev, bar)) != 0) {
-				curaddr = addr;
-				pcidev_dev = dev;
+				found_dev = dev;
 				found++;
 			}
 		}
@@ -240,14 +243,14 @@ uintptr_t pcidev_init(int bar, const struct dev_entry *devs)
 	/* Only continue if exactly one supported PCI dev has been found. */
 	if (found == 0) {
 		msg_perr("Error: No supported PCI device found.\n");
-		exit(1);
+		return NULL;
 	} else if (found > 1) {
 		msg_perr("Error: Multiple supported PCI devices found. Use 'flashrom -p xxxx:pci=bb:dd.f' \n"
 			 "to explicitly select the card with the given BDF (PCI bus, device, function).\n");
-		exit(1);
+		return NULL;
 	}
 
-	return curaddr;
+	return found_dev;
 }
 
 enum pci_write_type {