linux-toradex.git/sound/drivers/mpu401, branch v2.6.19.3

IRQ: Maintain regs pointer globally rather than passing to IRQ handlers

2006-10-05T14:10:12+00:00

Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells 
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

[ALSA] Deprecate snd_card_free_in_thread()

2006-09-23T08:37:03+00:00

Deprecated snd_card_free_in_thread(), replaced with
snd_card_free_when_closed().

Signed-off-by: Takashi Iwai 
Signed-off-by: Jaroslav Kysela

[PATCH] irq-flags: sound: Use the new IRQF_ constants

2006-07-02T20:58:54+00:00

Signed-off-by: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: "David S. Miller" 
Cc: Benjamin Herrenschmidt 
Cc: Jaroslav Kysela 
Cc: Takashi Iwai 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] 64bit resource: fix up printks for resources in sound drivers

2006-06-27T16:23:58+00:00

This is needed if we wish to change the size of the resource structures.

Based on an original patch from Vivek Goyal 

Cc: Vivek Goyal 
Signed-off-by: Andrew Morton 
Signed-off-by: Greg Kroah-Hartman

[ALSA] Change an arugment of snd_mpu401_uart_new() to bit flags

2006-06-22T19:33:56+00:00

Change the 5th argument of snd_mpu401_uart_new() to bit flags
instead of a boolean.  The argument takes bits that consist of
MPU401_INFO_XXX flags.
The callers that used the value 1 there are replaced with
MPU401_INFO_INTEGRATED.

Signed-off-by: Takashi Iwai

[ALSA] mpu401_uart - Fix coding style and code clean up

2006-06-22T19:33:51+00:00

- fold lines and fix spaces to follow the standard style
- added some comments
- moved EXPORT_SYMBOL() near the definition
- some code clean up

Signed-off-by: Takashi Iwai

[ALSA] unregister platform device again if probe was unsuccessful

2006-06-22T19:32:42+00:00

This second one unregisters the platform device again when the probe is
unsuccesful for sound/drivers, sound/arm/sa11xx-uda1341.c and
sound/ppc/powermac.c. This gets them all.

Signed-off-by: Rene Herman 
Signed-off-by: Takashi Iwai

[PATCH] mpu401 section fix

2006-05-21T19:59:22+00:00

WARNING: sound/drivers/mpu401/snd-mpu401.o - Section mismatch: reference to .init.text: from .text between 'snd_mpu401_pnp_probe' (at offset 0x1f7) and 'snd_mpu401_pnp_remove'

Cc: Jaroslav Kysela 
Cc: Takashi Iwai 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[ALSA] continue on IS_ERR from platform device registration

2006-04-27T19:10:08+00:00

I previously only concerned myself with sound/isa. When I now checked
for more platform_device_register_simple() usages in ALSA I found a
couple more drivers that needed the same patches as already submitted
for all the ISA drivers.
This first one is the continue-on-iserr patch for sound/drivers. This
gets them all.

Signed-off-by: Rene Herman 
Signed-off-by: Takashi Iwai

[PATCH] sound: fix hang in mpu401_uart.c

2006-04-20T14:54:04+00:00

This fixes a hang in mpu401_uart.c that can occur when the mpu401 interface
is non-existent or otherwise doesn't respond to commands but we issue IO
anyway.  snd_mpu401_uart_cmd now returns an error code that is passed up
the stack so that an open() will fail immediately in such cases.

Eventually discovered after wine/cxoffice would constantly cause hard
lockups on my desktop immediately after loading (emulating Windows too
well).  Turned out that I'd recently moved my sound cards around and using
/dev/sequencer now talks to a sound card with a broken MPU.

This second version changes -EFAULT to -EIO and frees open resources on
error too.  Test booted and seems to work ok.

Signed-off-by: Jon Masters 
Cc: Jaroslav Kysela 
Acked-by: Takashi Iwai 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds