[Lucid SRU] UBUNTU: SAUCE: dell-laptop: fire SMI when toggling hardware killswitch

[Stefan Bader]

The patch is small (Eric's comment about the line length should be taken care
of) but I wonder a bit about other systems. This adds setting a bit without
being obvious whether that get restricted to hw that requires it. What happens
on hw that does not require this special handling?
So I definitely want that to be coming back from upstream instead of SRU it
manually. Make  sure you submit it as a stable patch, then we will get it
automatically.

-Stefan

On 06/09/2010 09:44 AM, Keng-Yu Lin wrote:
> SRU Justification:
> 
> Impact:
> A type of Dell Inspiron Mini does not turn off bluetooth physically when
> pressing F2 (rfkill hotkey). 
> 
> Fix: 
> Current kernel code expects hardware to handle the hard-rfkill switching
> spontaneously and only notify rfkill subsystem with the status change.
> This patch makes kernel to explicitly fire a SMI to switch on/off
> rfkill devices if BIOS reports that the hardware switch is not supported.
> 
> This patch depends on the following sauce patch in lucid kernel so is not going upstream:
> 	UBUNTU: SAUCE: dell-laptop: Store the HW switch status internally rather than requerying every time
> 
> Testcase: 
> I tested the patch on a Dell Mini 10. It works smoothly.
> 
> --
> From b17359e833677297d4d5daf78e4d9dc460e51285 Mon Sep 17 00:00:00 2001
> From: Keng-Yu Lin <keng-yu.lin at canonical.com>
> Date: Thu, 3 Jun 2010 10:31:56 +0800
> Subject: [PATCH] UBUNTU: SAUCE: dell-laptop: fire SMI when toggling hardware killswitch
> 
> When BIOS reports hardware switch is not supported, it does not turn on/off all
> devices spontaneously. So it is neccessary to fire an SMI to switch the rfkill
> status explicitly when toggling the hardware killswitch.
> 
> BugLink: http://bugs.launchpad.net/bugs/590607
> 
> Signed-off-by: Keng-Yu Lin <keng-yu.lin at canonical.com>
> ---
>  drivers/platform/x86/dell-laptop.c |    4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c
> index 15d96a0..e54ab12 100644
> --- a/drivers/platform/x86/dell-laptop.c
> +++ b/drivers/platform/x86/dell-laptop.c
> @@ -29,6 +29,7 @@
>  #define WLAN_SWITCH_MASK 0
>  #define BT_SWITCH_MASK 1
>  #define WWAN_SWITCH_MASK 2
> +#define HW_SWITCH_SUPPORT 3
>  #define HW_SWITCH_MASK 16
>  
>  /* This structure will be modified by the firmware when we enter
> @@ -240,7 +241,7 @@ static int dell_rfkill_set(void *data, bool blocked)
>  	int disable = blocked ? 1 : 0;
>  	unsigned long radio = (unsigned long)data;
>  
> -	if (!(hw_switch_status & BIT(radio-1)) || !(hw_switch_status & BIT(HW_SWITCH_MASK))) {
> +	if (!(hw_switch_status & BIT(radio-1)) || !(hw_switch_status & BIT(HW_SWITCH_MASK)) || !(hw_switch_status & BIT(HW_SWITCH_SUPPORT))) {
>  		memset(&buffer, 0, sizeof(struct calling_interface_buffer));
>  		buffer.input[0] = (1 | (radio<<8) | (disable << 16));
>  		dell_send_request(&buffer, 17, 11);
> @@ -258,6 +259,7 @@ static void dell_rfkill_query(struct rfkill *rfkill, void *data)
>  	dell_send_request(&buffer, 17, 11);
>  	status = buffer.output[1];
>  
> +	hw_switch_status |= (status & BIT(0)) << BIT(HW_SWITCH_SUPPORT);
>  	hw_switch_status |= (status & BIT(HW_SWITCH_MASK)) ^ BIT(HW_SWITCH_MASK);
>  
>  	/* HW switch control not supported