Thadeu, thanks for the detailed analysis of the problem. Please test the commit below, it should fix things cleanly. I am quite tired right now, so I might have missed some details, but it survived a fast testing and compiled without warnings both with and without poll support compiled in. Tested in a T43 by crippling the input device open handle to not start the poller, and by crippling hotkey_mask support to force the driver to think it needs to default to poll mode. Both volume and brightness reporting worked fine in the test. If it does fixes the issues you observed, I will add the tested-by, and send it to Len. commit 8e05920a6cb236b21f31391b4479ec29ce65ccdf Author: Henrique de Moraes Holschuh <hmh@xxxxxxxxxx> Date: Mon Feb 8 22:40:28 2010 -0200 thinkpad-acpi: make driver events work in NVRAM poll mode Thadeu Lima de Souza Cascardo reports this: Brightness notification does not work until the user writes to hotkey_mask attribute. That's because the polling thread will only run if hotkey_user_mask is set and someone is reading the input device or if hotkey_driver_mask is set. In this second case, this condition is not tested after the mask is changed, because the brightness and volume drivers are started after the hotkey drivers. Fix tpacpi_hotkey_driver_mask_set() to call hotkey_poll_setup(), so that the poller kthread will be started when needed. Reported-by: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxxx> Signed-off-by: Henrique de Moraes Holschuh <hmh@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c index d12b61b..09c1fe6 100644 --- a/drivers/platform/x86/thinkpad_acpi.c +++ b/drivers/platform/x86/thinkpad_acpi.c @@ -2086,6 +2086,7 @@ static struct attribute_set *hotkey_dev_attributes; static void tpacpi_driver_event(const unsigned int hkey_event); static void hotkey_driver_event(const unsigned int scancode); +static void hotkey_poll_setup(const bool may_warn); /* HKEY.MHKG() return bits */ #define TP_HOTKEY_TABLET_MASK (1 << 3) @@ -2268,6 +2269,8 @@ static int tpacpi_hotkey_driver_mask_set(const u32 mask) rc = hotkey_mask_set((hotkey_acpi_mask | hotkey_driver_mask) & ~hotkey_source_mask); + hotkey_poll_setup(true); + mutex_unlock(&hotkey_mutex); return rc; @@ -2552,7 +2555,7 @@ static void hotkey_poll_stop_sync(void) } /* call with hotkey_mutex held */ -static void hotkey_poll_setup(bool may_warn) +static void hotkey_poll_setup(const bool may_warn) { const u32 poll_driver_mask = hotkey_driver_mask & hotkey_source_mask; const u32 poll_user_mask = hotkey_user_mask & hotkey_source_mask; @@ -2583,7 +2586,7 @@ static void hotkey_poll_setup(bool may_warn) } } -static void hotkey_poll_setup_safe(bool may_warn) +static void hotkey_poll_setup_safe(const bool may_warn) { mutex_lock(&hotkey_mutex); hotkey_poll_setup(may_warn); @@ -2601,7 +2604,11 @@ static void hotkey_poll_set_freq(unsigned int freq) #else /* CONFIG_THINKPAD_ACPI_HOTKEY_POLL */ -static void hotkey_poll_setup_safe(bool __unused) +static void hotkey_poll_setup(const bool __unused) +{ +} + +static void hotkey_poll_setup_safe(const bool __unused) { } -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html