[PATCH] leds-fsg: Change order of initialization anddeinitialization

From: Sven Wegener
Date: Sun Jul 27 2008 - 14:45:00 EST


On initialization, we first do the ioremap and then register the led devices.
On deinitialization, we do it in reverse order. This prevents someone calling
into the brightness_set functions with an invalid latch_address.

Signed-off-by: Sven Wegener <sven.wegener@xxxxxxxxxxx>
Cc: Rod Whitby <rod@xxxxxxxxxxxx>
---
drivers/leds/leds-fsg.c | 28 ++++++++++++++--------------
1 files changed, 14 insertions(+), 14 deletions(-)

I do not own a FSG-3, but it's probably a single CPU device and the chance
of hitting this race condition is unlikely, but we should do it right
nontheless. Further looking at the code, we probably also need a lock to
make changing latch_value fully atomic, but again it is unlikely to hit
this.

diff --git a/drivers/leds/leds-fsg.c b/drivers/leds/leds-fsg.c
index a7421b8..a26fe36 100644
--- a/drivers/leds/leds-fsg.c
+++ b/drivers/leds/leds-fsg.c
@@ -161,6 +161,16 @@ static int fsg_led_probe(struct platform_device *pdev)
{
int ret;

+ /* Map the LED chip select address space */
+ latch_address = (unsigned short *) ioremap(IXP4XX_EXP_BUS_BASE(2), 512);
+ if (!latch_address) {
+ ret = -ENOMEM;
+ goto failremap;
+ }
+
+ latch_value = 0xffff;
+ *latch_address = latch_value;
+
ret = led_classdev_register(&pdev->dev, &fsg_wlan_led);
if (ret < 0)
goto failwlan;
@@ -185,20 +195,8 @@ static int fsg_led_probe(struct platform_device *pdev)
if (ret < 0)
goto failring;

- /* Map the LED chip select address space */
- latch_address = (unsigned short *) ioremap(IXP4XX_EXP_BUS_BASE(2), 512);
- if (!latch_address) {
- ret = -ENOMEM;
- goto failremap;
- }
-
- latch_value = 0xffff;
- *latch_address = latch_value;
-
return ret;

- failremap:
- led_classdev_unregister(&fsg_ring_led);
failring:
led_classdev_unregister(&fsg_sync_led);
failsync:
@@ -210,14 +208,14 @@ static int fsg_led_probe(struct platform_device *pdev)
failwan:
led_classdev_unregister(&fsg_wlan_led);
failwlan:
+ iounmap(latch_address);
+ failremap:

return ret;
}

static int fsg_led_remove(struct platform_device *pdev)
{
- iounmap(latch_address);
-
led_classdev_unregister(&fsg_wlan_led);
led_classdev_unregister(&fsg_wan_led);
led_classdev_unregister(&fsg_sata_led);
@@ -225,6 +223,8 @@ static int fsg_led_remove(struct platform_device *pdev)
led_classdev_unregister(&fsg_sync_led);
led_classdev_unregister(&fsg_ring_led);

+ iounmap(latch_address);
+
return 0;
}

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