[patch 17/17] drivers/input/serio/hp_sdc.c: fix crash when removing hp_sdc module
From: akpm@linux-foundation.org
Date: 2009-01-09 20:37:16
From: Helge Deller <deller@gmx.de> On parisc machines, which don't have HIL, removing the hp_sdc module panics the kernel. Fix this by returning early in hp_sdc_exit() if no HP SDC controller was found. Add functionality to probe for the hp_sdc_mlc kernel module (which takes care of the upper layer HIL functionality on parisc) after two seconds. This is needed to get all the other HIL drivers (keyboard / mouse/ ..) drivers automatically loaded by udev later as well. Signed-off-by: Helge Deller <deller@gmx.de> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Frans Pop <redacted> Cc: Kyle McMartin <redacted> Cc: Grant Grundler <redacted> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- drivers/input/serio/hp_sdc.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff -puN drivers/input/serio/hp_sdc.c~drivers-input-serio-hp_sdcc-fix-crash-when-removing-hp_sdc-module drivers/input/serio/hp_sdc.c
--- a/drivers/input/serio/hp_sdc.c~drivers-input-serio-hp_sdcc-fix-crash-when-removing-hp_sdc-module
+++ a/drivers/input/serio/hp_sdc.c@@ -819,6 +819,7 @@ static const struct parisc_device_id hp_ MODULE_DEVICE_TABLE(parisc, hp_sdc_tbl); static int __init hp_sdc_init_hppa(struct parisc_device *d); +static struct delayed_work moduleloader_work; static struct parisc_driver hp_sdc_driver = { .name = "hp_sdc",
@@ -930,8 +931,15 @@ static int __init hp_sdc_init(void) #if defined(__hppa__) +static void request_module_delayed(struct work_struct *work) +{ + request_module("hp_sdc_mlc"); +} + static int __init hp_sdc_init_hppa(struct parisc_device *d) { + int ret; + if (!d) return 1; if (hp_sdc.dev != NULL)
@@ -944,13 +952,26 @@ static int __init hp_sdc_init_hppa(struc hp_sdc.data_io = d->hpa.start + 0x800; hp_sdc.status_io = d->hpa.start + 0x801; - return hp_sdc_init(); + INIT_DELAYED_WORK(&moduleloader_work, request_module_delayed); + + ret = hp_sdc_init(); + /* after sucessfull initialization give SDC some time to settle + * and then load the hp_sdc_mlc upper layer driver */ + if (!ret) + schedule_delayed_work(&moduleloader_work, + msecs_to_jiffies(2000)); + + return ret; } #endif /* __hppa__ */ static void hp_sdc_exit(void) { + /* do nothing if we don't have a SDC */ + if (!hp_sdc.dev) + return; + write_lock_irq(&hp_sdc.lock); /* Turn off all maskable "sub-function" irq's. */
@@ -969,6 +990,7 @@ static void hp_sdc_exit(void) tasklet_kill(&hp_sdc.task); #if defined(__hppa__) + cancel_delayed_work_sync(&moduleloader_work); if (unregister_parisc_driver(&hp_sdc_driver)) printk(KERN_WARNING PREFIX "Error unregistering HP SDC"); #endif
_