ALSA: hda/tegra: implement runtime suspend/resume

This patch moves clock enable/disable from system resume/suspend to
runtime resume/suspend respectively. Along with this hda controller
chip init or stop is also moved. System resume/suspend can invoke
runtime callbacks and do necessary setup.

chip->running can be used to check for probe completion and device
access during runtime_resume or runtime_suspend can be avoided if
probe is not yet finished. This helps to avoid kernel panic during
boot where runtime PM callbacks can happen from system PM.

Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Reviewed-by: Ravindra Lokhande <rlokhande@nvidia.com>
Reviewed-by: Mohan Kumar D <mkumard@nvidia.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/pci/hda/hda_tegra.c b/sound/pci/hda/hda_tegra.c
index f068b1e..a7fd4c6 100644 (file)
--- a/sound/pci/hda/hda_tegra.c
+++ b/sound/pci/hda/hda_tegra.c
@@ -233,32 +233,24 @@ static void hda_tegra_disable_clocks(struct hda_tegra *data)
 static int hda_tegra_suspend(struct device *dev)
 {
        struct snd_card *card = dev_get_drvdata(dev);
-       struct azx *chip = card->private_data;
-       struct hda_tegra *hda = container_of(chip, struct hda_tegra, chip);
-       struct hdac_bus *bus = azx_bus(chip);
+       int rc;
 
+       rc = pm_runtime_force_suspend(dev);
+       if (rc < 0)
+               return rc;
        snd_power_change_state(card, SNDRV_CTL_POWER_D3hot);
 
-       azx_stop_chip(chip);
-       synchronize_irq(bus->irq);
-       azx_enter_link_reset(chip);
-       hda_tegra_disable_clocks(hda);
-
        return 0;
 }
 
 static int hda_tegra_resume(struct device *dev)
 {
        struct snd_card *card = dev_get_drvdata(dev);
-       struct azx *chip = card->private_data;
-       struct hda_tegra *hda = container_of(chip, struct hda_tegra, chip);
-
-       hda_tegra_enable_clocks(hda);
-
-       hda_tegra_init(hda);
-
-       azx_init_chip(chip, 1);
+       int rc;
 
+       rc = pm_runtime_force_resume(dev);
+       if (rc < 0)
+               return rc;
        snd_power_change_state(card, SNDRV_CTL_POWER_D0);
 
        return 0;
@@ -268,11 +260,36 @@ static int hda_tegra_resume(struct device *dev)
 #ifdef CONFIG_PM
 static int hda_tegra_runtime_suspend(struct device *dev)
 {
+       struct snd_card *card = dev_get_drvdata(dev);
+       struct azx *chip = card->private_data;
+       struct hda_tegra *hda = container_of(chip, struct hda_tegra, chip);
+       struct hdac_bus *bus = azx_bus(chip);
+
+       if (chip && chip->running) {
+               azx_stop_chip(chip);
+               synchronize_irq(bus->irq);
+               azx_enter_link_reset(chip);
+       }
+       hda_tegra_disable_clocks(hda);
+
        return 0;
 }
 
 static int hda_tegra_runtime_resume(struct device *dev)
 {
+       struct snd_card *card = dev_get_drvdata(dev);
+       struct azx *chip = card->private_data;
+       struct hda_tegra *hda = container_of(chip, struct hda_tegra, chip);
+       int rc;
+
+       rc = hda_tegra_enable_clocks(hda);
+       if (rc != 0)
+               return rc;
+       if (chip && chip->running) {
+               hda_tegra_init(hda);
+               azx_init_chip(chip, 1);
+       }
+
        return 0;
 }
 #endif /* CONFIG_PM */