[alsa-devel] [PATCH 3/4 V6] ALSA: hda - Add power-welll support for haswell HDA
Wang Xingchao
xingchao.wang at linux.intel.com
Mon May 27 11:15:15 CEST 2013
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: Wang Xingchao <xingchao.wang at linux.intel.com>
---
sound/pci/hda/Kconfig | 10 ++++++
sound/pci/hda/Makefile | 2 ++
sound/pci/hda/hda_i915.c | 75 +++++++++++++++++++++++++++++++++++++++++++++
sound/pci/hda/hda_i915.h | 35 +++++++++++++++++++++
sound/pci/hda/hda_intel.c | 60 ++++++++++++++++++++++++++++++++++--
5 files changed, 179 insertions(+), 3 deletions(-)
create mode 100644 sound/pci/hda/hda_i915.c
create mode 100644 sound/pci/hda/hda_i915.h
diff --git a/sound/pci/hda/Kconfig b/sound/pci/hda/Kconfig
index 80a7d44..c5a872c 100644
--- a/sound/pci/hda/Kconfig
+++ b/sound/pci/hda/Kconfig
@@ -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
diff --git a/sound/pci/hda/Makefile b/sound/pci/hda/Makefile
index 24a2514..c091438 100644
--- a/sound/pci/hda/Makefile
+++ b/sound/pci/hda/Makefile
@@ -1,4 +1,6 @@
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
diff --git a/sound/pci/hda/hda_i915.c b/sound/pci/hda/hda_i915.c
new file mode 100644
index 0000000..76c13d5
--- /dev/null
+++ b/sound/pci/hda/hda_i915.c
@@ -0,0 +1,75 @@
+/*
+ * 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;
+}
diff --git a/sound/pci/hda/hda_i915.h b/sound/pci/hda/hda_i915.h
new file mode 100644
index 0000000..5a63da2
--- /dev/null
+++ b/sound/pci/hda/hda_i915.h
@@ -0,0 +1,35 @@
+/*
+ * 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
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 49cc942..1dedcb1 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -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 \
@@ -2869,6 +2875,8 @@ 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;
}
@@ -2881,6 +2889,8 @@ 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) {
@@ -2913,6 +2923,8 @@ 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;
}
@@ -2921,6 +2933,8 @@ 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;
@@ -3147,6 +3161,10 @@ 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;
@@ -3372,6 +3390,13 @@ 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
*/
@@ -3447,7 +3472,13 @@ 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;
}
@@ -3718,6 +3749,16 @@ 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)
@@ -3740,6 +3781,16 @@ 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;
@@ -3834,11 +3885,14 @@ 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 },
--
1.7.9.5
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