Commit 99a2008d authored by Wang Xingchao's avatar Wang Xingchao Committed by Daniel Vetter
Browse files

ALSA: hda - Add power-welll support for haswell HDA 



For Intel Haswell chip, HDA controller and codec have
power well dependency from GPU side. This patch added support
to request/release power well in audio driver. Power save
feature should be enabled to get runtime power saving.

There's deadlock when request_module(i915) in azx_probe.
It looks like:
device_lock(audio pci device) -> azx_probe -> module_request
(or symbol_request) -> modprobe (userspace) -> i915 init ->
drm_pci_init -> pci_register_driver -> bus_add_driver -> driver_attach ->
which in turn tries all locks on pci bus, and when it tries the one on the
audio device, it will deadlock.

This patch introduce a work to store remaining probe stuff, and let
request_module run in safe work context.

Signed-off-by: default avatarWang Xingchao <xingchao.wang@linux.intel.com>
Reviewed-by: default avatarTakashi Iwai <tiwai@suse.de>
Reviewed-by: default avatarLiam Girdwood <liam.r.girdwood@intel.com>
Reviewed-by: default avatarDavid Henningsson <david.henningsson@canonical.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent 5c90680e

sound/pci/hda/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -152,6 +152,16 @@ config SND_HDA_CODEC_HDMI 
	  snd-hda-codec-hdmi.

	  This module is automatically loaded at probing.



config SND_HDA_I915

	bool "Build Display HD-audio controller/codec power well support for i915 cards"

	depends on DRM_I915

	help

	  Say Y here to include full HDMI and DisplayPort HD-audio controller/codec

	  power-well support for Intel Haswell graphics cards based on the i915 driver.



	  Note that this option must be enabled for Intel Haswell C+ stepping machines, otherwise

	  the GPU audio controller/codecs will not be initialized or damaged when exit from S3 mode.



config SND_HDA_CODEC_CIRRUS

	bool "Build Cirrus Logic codec support"

	default y

sound/pci/hda/Makefile

+2 −0
Original line number Diff line number Diff line 
snd-hda-intel-objs := hda_intel.o

# for haswell power well

snd-hda-intel-$(CONFIG_SND_HDA_I915) +=	hda_i915.o



snd-hda-codec-y := hda_codec.o hda_jack.o hda_auto_parser.o

snd-hda-codec-$(CONFIG_SND_HDA_GENERIC) += hda_generic.o

sound/pci/hda/hda_i915.c

0 → 100644
+75 −0
Original line number Diff line number Diff line 
/*

 *  hda_i915.c - routines for Haswell HDA controller power well support

 *

 *  This program is free software; you can redistribute it and/or modify it

 *  under the terms of the GNU General Public License as published by the Free

 *  Software Foundation; either version 2 of the License, or (at your option)

 *  any later version.

 *

 *  This program is distributed in the hope that it will be useful, but

 *  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY

 *  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 *  for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software Foundation,

 *  Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

 */



#include <linux/init.h>

#include <linux/module.h>

#include <sound/core.h>

#include <drm/i915_powerwell.h>

#include "hda_i915.h"



static void (*get_power)(void);

static void (*put_power)(void);



void hda_display_power(bool enable)

{

	if (!get_power || !put_power)

		return;



	snd_printdd("HDA display power %s \n",

			enable ? "Enable" : "Disable");

	if (enable)

		get_power();

	else

		put_power();

}



int hda_i915_init(void)

{

	int err = 0;



	get_power = symbol_request(i915_request_power_well);

	if (!get_power) {

		snd_printk(KERN_WARNING "hda-i915: get_power symbol get fail\n");

		return -ENODEV;

	}



	put_power = symbol_request(i915_release_power_well);

	if (!put_power) {

		symbol_put(i915_request_power_well);

		get_power = NULL;

		return -ENODEV;

	}



	snd_printd("HDA driver get symbol successfully from i915 module\n");



	return err;

}



int hda_i915_exit(void)

{

	if (get_power) {

		symbol_put(i915_request_power_well);

		get_power = NULL;

	}

	if (put_power) {

		symbol_put(i915_release_power_well);

		put_power = NULL;

	}



	return 0;

}

sound/pci/hda/hda_i915.h

0 → 100644
+35 −0
Original line number Diff line number Diff line 
/*

 *  This program is free software; you can redistribute it and/or modify it

 *  under the terms of the GNU General Public License as published by the Free

 *  Software Foundation; either version 2 of the License, or (at your option)

 *  any later version.

 *

 *  This program is distributed in the hope that it will be useful, but WITHOUT

 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for

 *  more details.

 *

 *  You should have received a copy of the GNU General Public License along with

 *  this program; if not, write to the Free Software Foundation, Inc., 59

 *  Temple Place - Suite 330, Boston, MA  02111-1307, USA.

 */

#ifndef __SOUND_HDA_I915_H

#define __SOUND_HDA_I915_H



#ifdef CONFIG_SND_HDA_I915

void hda_display_power(bool enable);

int hda_i915_init(void);

int hda_i915_exit(void);

#else

static inline void hda_display_power(bool enable) {}

static inline int hda_i915_init(void)

{

	return -ENODEV;

}

static inline int hda_i915_exit(void)

{

	return 0;

}

#endif



#endif

sound/pci/hda/hda_intel.c

+57 −3
Original line number Diff line number Diff line
@@ -62,6 +62,7 @@ 
#include <linux/vga_switcheroo.h>

#include <linux/firmware.h>

#include "hda_codec.h"

#include "hda_i915.h"





static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
@@ -541,6 +542,10 @@ struct azx { 
	/* for pending irqs */

	struct work_struct irq_pending_work;



#ifdef CONFIG_SND_HDA_I915

	struct work_struct probe_work;

#endif



	/* reboot notifier (for mysterious hangup problem at power-down) */

	struct notifier_block reboot_notifier;
@@ -594,6 +599,7 @@ enum { 
#define AZX_DCAPS_4K_BDLE_BOUNDARY (1 << 23)	/* BDLE in 4k boundary */

#define AZX_DCAPS_COUNT_LPIB_DELAY  (1 << 25)	/* Take LPIB as delay */

#define AZX_DCAPS_PM_RUNTIME	(1 << 26)	/* runtime PM support */

#define AZX_DCAPS_I915_POWERWELL (1 << 27)	/* HSW i915 power well support */



/* quirks for Intel PCH */

#define AZX_DCAPS_INTEL_PCH_NOPM \
@@ -2900,6 +2906,8 @@ static int azx_suspend(struct device *dev) 
	pci_disable_device(pci);

	pci_save_state(pci);

	pci_set_power_state(pci, PCI_D3hot);

	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)

		hda_display_power(false);

	return 0;

}
@@ -2912,6 +2920,8 @@ static int azx_resume(struct device *dev) 
	if (chip->disabled)

		return 0;



	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)

		hda_display_power(true);

	pci_set_power_state(pci, PCI_D0);

	pci_restore_state(pci);

	if (pci_enable_device(pci) < 0) {
@@ -2944,6 +2954,8 @@ static int azx_runtime_suspend(struct device *dev) 


	azx_stop_chip(chip);

	azx_clear_irq_pending(chip);

	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)

		hda_display_power(false);

	return 0;

}
@@ -2952,6 +2964,8 @@ static int azx_runtime_resume(struct device *dev) 
	struct snd_card *card = dev_get_drvdata(dev);

	struct azx *chip = card->private_data;



	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)

		hda_display_power(true);

	azx_init_pci(chip);

	azx_init_chip(chip, 1);

	return 0;
@@ -3176,6 +3190,10 @@ static int azx_free(struct azx *chip) 
	if (chip->fw)

		release_firmware(chip->fw);

#endif

	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {

		hda_display_power(false);

		hda_i915_exit();

	}

	kfree(chip);



	return 0;
@@ -3401,6 +3419,13 @@ static void azx_check_snoop_available(struct azx *chip) 
	}

}



#ifdef CONFIG_SND_HDA_I915

static void azx_probe_work(struct work_struct *work)

{

	azx_probe_continue(container_of(work, struct azx, probe_work));

}

#endif



/*

 * constructor

 */
@@ -3476,7 +3501,13 @@ static int azx_create(struct snd_card *card, struct pci_dev *pci, 
		return err;

	}



#ifdef CONFIG_SND_HDA_I915

	/* continue probing in work context as may trigger request module */

	INIT_WORK(&chip->probe_work, azx_probe_work);

#endif



	*rchip = chip;



	return 0;

}
@@ -3747,6 +3778,16 @@ static int azx_probe(struct pci_dev *pci, 
	}

#endif /* CONFIG_SND_HDA_PATCH_LOADER */



	/* continue probing in work context, avoid request_module deadlock */

	if (probe_now && (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)) {

#ifdef CONFIG_SND_HDA_I915

		probe_now = false;

		schedule_work(&chip->probe_work);

#else

		snd_printk(KERN_ERR SFX "Haswell must build in CONFIG_SND_HDA_I915\n");

#endif

	}



	if (probe_now) {

		err = azx_probe_continue(chip);

		if (err < 0)
@@ -3769,6 +3810,16 @@ static int azx_probe_continue(struct azx *chip) 
	int dev = chip->dev_index;

	int err;



	/* Request power well for Haswell HDA controller and codec */

	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {

		err = hda_i915_init();

		if (err < 0) {

			snd_printk(KERN_ERR SFX "Error request power-well from i915\n");

			goto out_free;

		}

		hda_display_power(true);

	}



	err = azx_first_init(chip);

	if (err < 0)

		goto out_free;
@@ -3863,11 +3914,14 @@ static DEFINE_PCI_DEVICE_TABLE(azx_ids) = { 
	  .driver_data = AZX_DRIVER_PCH | AZX_DCAPS_INTEL_PCH },

	/* Haswell */

	{ PCI_DEVICE(0x8086, 0x0a0c),

	  .driver_data = AZX_DRIVER_SCH | AZX_DCAPS_INTEL_PCH },

	  .driver_data = AZX_DRIVER_SCH | AZX_DCAPS_INTEL_PCH |

	  AZX_DCAPS_I915_POWERWELL },

	{ PCI_DEVICE(0x8086, 0x0c0c),

	  .driver_data = AZX_DRIVER_SCH | AZX_DCAPS_INTEL_PCH },

	  .driver_data = AZX_DRIVER_SCH | AZX_DCAPS_INTEL_PCH |

	  AZX_DCAPS_I915_POWERWELL },

	{ PCI_DEVICE(0x8086, 0x0d0c),

	  .driver_data = AZX_DRIVER_SCH | AZX_DCAPS_INTEL_PCH },

	  .driver_data = AZX_DRIVER_SCH | AZX_DCAPS_INTEL_PCH |

	  AZX_DCAPS_I915_POWERWELL },

	/* 5 Series/3400 */

	{ PCI_DEVICE(0x8086, 0x3b56),

	  .driver_data = AZX_DRIVER_SCH | AZX_DCAPS_INTEL_PCH_NOPM },