diff mbox series

[RFC,v2,12/22] sound: usb: card: Introduce USB SND platform op callbacks

Message ID 20230126031424.14582-13-quic_wcheng@quicinc.com
State New
Headers show
Series Introduce QC USB SND audio offloading support | expand

Commit Message

Wesley Cheng Jan. 26, 2023, 3:14 a.m. UTC
Allow for different platforms to be notified on USB SND connect/disconnect
seqeunces.  This allows for platform USB SND modules to properly initialize
and populate internal structures with references to the USB SND chip
device.

Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
---
 sound/usb/card.c | 28 ++++++++++++++++++++++++++++
 sound/usb/card.h | 20 ++++++++++++++++++++
 2 files changed, 48 insertions(+)

Comments

Greg KH Jan. 28, 2023, 1:28 p.m. UTC | #1
On Wed, Jan 25, 2023 at 07:14:14PM -0800, Wesley Cheng wrote:
> Allow for different platforms to be notified on USB SND connect/disconnect
> seqeunces.  This allows for platform USB SND modules to properly initialize
> and populate internal structures with references to the USB SND chip
> device.
> 
> Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
> ---
>  sound/usb/card.c | 28 ++++++++++++++++++++++++++++
>  sound/usb/card.h | 20 ++++++++++++++++++++
>  2 files changed, 48 insertions(+)
> 
> diff --git a/sound/usb/card.c b/sound/usb/card.c
> index 26268ffb8274..803230343c16 100644
> --- a/sound/usb/card.c
> +++ b/sound/usb/card.c
> @@ -117,6 +117,24 @@ MODULE_PARM_DESC(skip_validation, "Skip unit descriptor validation (default: no)
>  static DEFINE_MUTEX(register_mutex);
>  static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
>  static struct usb_driver usb_audio_driver;
> +static struct snd_usb_platform_ops *platform_ops;

You can not have a single "platform_ops" pointer, this HAS to be
per-bus.

And what is a "platform operations" anyway?  Shouldn't this be a driver
type or something like that?  "offload_operations"?

> +
> +int snd_usb_register_platform_ops(struct snd_usb_platform_ops *ops)
> +{
> +	if (platform_ops)
> +		return -EEXIST;
> +
> +	platform_ops = ops;
> +	return 0;

No locking?  not good.

But again, this has to be per-USB-bus, it can NOT be system wide for
obvious reasons.

thanks,

greg k-h
Albert Wang Feb. 20, 2023, 5:11 p.m. UTC | #2
Hi Wesley,

It looks like your audio offload driver will fetch the required
resources for a stream enable request. But we have different designs.
In the integration with your patch set, we found we still need a call
back function in card.c when the usb set interface is done, in which
we would call the new API, xhci_get_xfer_resource(), to get the EP
transfer ring address. Of course, we will try the
platform_ops->connect_cb() first to see if it is able to cover what we
need or not.


Thanks,
Albert Wang

Albert Wang | Pixel USB Software  | albertccwang@google.com | +886-918-695-245


On Thu, Jan 26, 2023 at 11:16 AM Wesley Cheng <quic_wcheng@quicinc.com> wrote:
>
> Allow for different platforms to be notified on USB SND connect/disconnect
> seqeunces.  This allows for platform USB SND modules to properly initialize
> and populate internal structures with references to the USB SND chip
> device.
>
> Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
> ---
>  sound/usb/card.c | 28 ++++++++++++++++++++++++++++
>  sound/usb/card.h | 20 ++++++++++++++++++++
>  2 files changed, 48 insertions(+)
>
> diff --git a/sound/usb/card.c b/sound/usb/card.c
> index 26268ffb8274..803230343c16 100644
> --- a/sound/usb/card.c
> +++ b/sound/usb/card.c
> @@ -117,6 +117,24 @@ MODULE_PARM_DESC(skip_validation, "Skip unit descriptor validation (default: no)
>  static DEFINE_MUTEX(register_mutex);
>  static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
>  static struct usb_driver usb_audio_driver;
> +static struct snd_usb_platform_ops *platform_ops;
> +
> +int snd_usb_register_platform_ops(struct snd_usb_platform_ops *ops)
> +{
> +       if (platform_ops)
> +               return -EEXIST;
> +
> +       platform_ops = ops;
> +       return 0;
> +}
> +EXPORT_SYMBOL_GPL(snd_usb_register_platform_ops);
> +
> +int snd_usb_unregister_platform_ops(void)
> +{
> +       platform_ops = NULL;
> +       return 0;
> +}
> +EXPORT_SYMBOL_GPL(snd_usb_unregister_platform_ops);
>
>  /*
>   * disconnect streams
> @@ -910,6 +928,10 @@ static int usb_audio_probe(struct usb_interface *intf,
>         usb_set_intfdata(intf, chip);
>         atomic_dec(&chip->active);
>         mutex_unlock(&register_mutex);
> +
> +       if (platform_ops->connect_cb)
> +               platform_ops->connect_cb(intf, chip);
> +
>         return 0;
>
>   __error:
> @@ -943,6 +965,9 @@ static void usb_audio_disconnect(struct usb_interface *intf)
>         if (chip == USB_AUDIO_IFACE_UNUSED)
>                 return;
>
> +       if (platform_ops->disconnect_cb)
> +               platform_ops->disconnect_cb(intf);
> +
>         card = chip->card;
>
>         mutex_lock(&register_mutex);
> @@ -1087,6 +1112,9 @@ static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
>                 chip->system_suspend = chip->num_suspended_intf;
>         }
>
> +       if (platform_ops->suspend_cb)
> +               platform_ops->suspend_cb(intf, message);
> +
>         return 0;
>  }
>
> diff --git a/sound/usb/card.h b/sound/usb/card.h
> index 40061550105a..2249c411c3a1 100644
> --- a/sound/usb/card.h
> +++ b/sound/usb/card.h
> @@ -206,4 +206,24 @@ struct snd_usb_stream {
>         struct list_head list;
>  };
>
> +struct snd_usb_platform_ops {
> +       void (*connect_cb)(struct usb_interface *intf, struct snd_usb_audio *chip);
> +       void (*disconnect_cb)(struct usb_interface *intf);
> +       void (*suspend_cb)(struct usb_interface *intf, pm_message_t message);
> +};
> +
> +#if IS_ENABLED(CONFIG_SND_USB_AUDIO)
> +int snd_usb_register_platform_ops(struct snd_usb_platform_ops *ops);
> +int snd_usb_unregister_platform_ops(void);
> +#else
> +int snd_usb_register_platform_ops(struct snd_usb_platform_ops *ops)
> +{
> +       return -EOPNOTSUPP;
> +}
> +
> +int snd_usb_unregister_platform_ops(void)
> +{
> +       return -EOPNOTSUPP;
> +}
> +#endif /* IS_ENABLED(CONFIG_SND_USB_AUDIO) */
>  #endif /* __USBAUDIO_CARD_H */
diff mbox series

Patch

diff --git a/sound/usb/card.c b/sound/usb/card.c
index 26268ffb8274..803230343c16 100644
--- a/sound/usb/card.c
+++ b/sound/usb/card.c
@@ -117,6 +117,24 @@  MODULE_PARM_DESC(skip_validation, "Skip unit descriptor validation (default: no)
 static DEFINE_MUTEX(register_mutex);
 static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
 static struct usb_driver usb_audio_driver;
+static struct snd_usb_platform_ops *platform_ops;
+
+int snd_usb_register_platform_ops(struct snd_usb_platform_ops *ops)
+{
+	if (platform_ops)
+		return -EEXIST;
+
+	platform_ops = ops;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_usb_register_platform_ops);
+
+int snd_usb_unregister_platform_ops(void)
+{
+	platform_ops = NULL;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_usb_unregister_platform_ops);
 
 /*
  * disconnect streams
@@ -910,6 +928,10 @@  static int usb_audio_probe(struct usb_interface *intf,
 	usb_set_intfdata(intf, chip);
 	atomic_dec(&chip->active);
 	mutex_unlock(&register_mutex);
+
+	if (platform_ops->connect_cb)
+		platform_ops->connect_cb(intf, chip);
+
 	return 0;
 
  __error:
@@ -943,6 +965,9 @@  static void usb_audio_disconnect(struct usb_interface *intf)
 	if (chip == USB_AUDIO_IFACE_UNUSED)
 		return;
 
+	if (platform_ops->disconnect_cb)
+		platform_ops->disconnect_cb(intf);
+
 	card = chip->card;
 
 	mutex_lock(&register_mutex);
@@ -1087,6 +1112,9 @@  static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message)
 		chip->system_suspend = chip->num_suspended_intf;
 	}
 
+	if (platform_ops->suspend_cb)
+		platform_ops->suspend_cb(intf, message);
+
 	return 0;
 }
 
diff --git a/sound/usb/card.h b/sound/usb/card.h
index 40061550105a..2249c411c3a1 100644
--- a/sound/usb/card.h
+++ b/sound/usb/card.h
@@ -206,4 +206,24 @@  struct snd_usb_stream {
 	struct list_head list;
 };
 
+struct snd_usb_platform_ops {
+	void (*connect_cb)(struct usb_interface *intf, struct snd_usb_audio *chip);
+	void (*disconnect_cb)(struct usb_interface *intf);
+	void (*suspend_cb)(struct usb_interface *intf, pm_message_t message);
+};
+
+#if IS_ENABLED(CONFIG_SND_USB_AUDIO)
+int snd_usb_register_platform_ops(struct snd_usb_platform_ops *ops);
+int snd_usb_unregister_platform_ops(void);
+#else
+int snd_usb_register_platform_ops(struct snd_usb_platform_ops *ops)
+{
+	return -EOPNOTSUPP;
+}
+
+int snd_usb_unregister_platform_ops(void)
+{
+	return -EOPNOTSUPP;
+}
+#endif /* IS_ENABLED(CONFIG_SND_USB_AUDIO) */
 #endif /* __USBAUDIO_CARD_H */