[PATCH v4 02/12] ALSA: ac97: add an ac97 bus

Takashi Iwai [off-list ref] writes:

On Mon, 24 Jul 2017 22:49:18 +0200,
Robert Jarzmik wrote:

...zip...

quoted

+#ifndef AC97_COMPAT_H
+#define AC97_COMPAT_H
+
+#include <sound/ac97_codec.h>
+#include <sound/soc.h>

Is this inclusion needed?  The code here doesn't look ASoC-specific at
all.

Mmm no, actually it's not, good point.

...zip...

quoted

+#ifndef AC97_CONTROLLER_H
+#define AC97_CONTROLLER_H
+
+#include <linux/list.h>
+
+#define AC97_BUS_MAX_CODECS 4
+#define AC97_SLOTS_AVAILABLE_ALL 0xf
+
+struct device;

You need the definition struct device in below (it's no pointer), thus
you have to include <linux/device.h> instead.

Fair enough, vor v5.

quoted

+struct ac97_controller {
+	const struct ac97_controller_ops *ops;

The struct isn't declared beforehand?  GCC will warn.

Actually it doesn't.
It's interesting as ac97_controller depends on ac97_controller_ops, and
ac97_controller_ops depends on ac97_controller;

As for why it doesn't warn, every time I used controller.h, I also used
codec.h. And codec.h holds a :
struct ac97_controller;

So it's declared beforehand after all ...

But I will add before "struct ac97_controller" a :
struct ac97_controller_ops;

quoted

+	struct list_head controllers;
+	struct device adap;
+	int nr;
+	struct device *parent;
+	unsigned short slots_available;

I'd move parent field below, so that 64bit pointer can be aligned
better.

Okay, got it.

...zip...

quoted

+
+	device_initialize(&codec->dev);
+	dev_set_name(&codec->dev, "%s:%u", dev_name(ac97_ctrl->parent), idx);
+
+	ret = device_add(&codec->dev);
+	if (ret)
+		goto err_free_codec;
+
+	return 0;
+err_free_codec:
+	kfree(codec);

This may leave the device name string.  You need to call
put_device() even if device_add() returns an error.

You're right, I'll change that.

...zip...

quoted

+int snd_ac97_codec_driver_register(struct ac97_codec_driver *drv)
+{
+	int ret;
+
+	drv->driver.bus = &ac97_bus_type;
+	ret = driver_register(&drv->driver);
+
+	return ret;

This can be simplified.

Indeed.

quoted

+}
+EXPORT_SYMBOL(snd_ac97_codec_driver_register);

No GPL?  (Ditto for other entries, too)

Euh yeah, GPL forever. I will change all the occurrences.

quoted

+int snd_ac97_reset(struct snd_ac97 *ac97, bool try_warm, unsigned int id,
+	unsigned int id_mask)
+{
+	struct ac97_codec_device *adev = to_ac97_device(ac97->private_data);
+	struct ac97_controller *actrl = adev->ac97_ctrl;
+
+	if (try_warm) {
+		compat_ac97_warm_reset(ac97);
+		if (snd_ac97_bus_scan_one(actrl, adev->num) == adev->vendor_id)

Can we ignore id_mask here?  I'm not quite sure whether it's fixed...

Probably not, but I will take a bit more time to cross-check that one.

Thanks for the review, I'll follow up on that last question when I'll have
settled on the correct answer.

Cheers.

-- 
Robert