ALSA: echoaudio: Allocate resources with device-managed APIs

This patch converts the resource management in PCI echoaudio drivers
with devres as a clean up. Each manual resource management is
converted with the corresponding devres helper, the page allocations
are done with the devres helper, and the card object release is
managed now via card->private_free instead of a lowlevel snd_device.
The irq handler is still managed manually because it's re-acquired at
PM suspend/resume.

This should give no user-visible functional changes.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Takashi Iwai <[e-mail]>

sound/pci/echoaudio/echoaudio.c

···
 	Module construction / destruction
 ******************************************************************************/
 
-static int snd_echo_free(struct echoaudio *chip)
+static void snd_echo_free(struct snd_card *card)
 {
+	struct echoaudio *chip = card->private_data;
+
 	if (chip->comm_page)
 		rest_in_peace(chip);
 
 	if (chip->irq >= 0)
 		free_irq(chip->irq, chip);
 
-	if (chip->comm_page)
-		snd_dma_free_pages(&chip->commpage_dma_buf);
-
-	iounmap(chip->dsp_registers);
-	release_and_free_resource(chip->iores);
-	pci_disable_device(chip->pci);
-
 	/* release chip data */
 	free_firmware_cache(chip);
-	kfree(chip);
-	return 0;
 }
-
-
-
-static int snd_echo_dev_free(struct snd_device *device)
-{
-	struct echoaudio *chip = device->device_data;
-
-	return snd_echo_free(chip);
-}
-
-
 
 /* <--snd_echo_probe() */
 static int snd_echo_create(struct snd_card *card,
-			   struct pci_dev *pci,
-			   struct echoaudio **rchip)
+			   struct pci_dev *pci)
 {
-	struct echoaudio *chip;
+	struct echoaudio *chip = card->private_data;
 	int err;
 	size_t sz;
-	static const struct snd_device_ops ops = {
-		.dev_free = snd_echo_dev_free,
-	};
-
-	*rchip = NULL;
 
 	pci_write_config_byte(pci, PCI_LATENCY_TIMER, 0xC0);
 
-	err = pci_enable_device(pci);
+	err = pcim_enable_device(pci);
 	if (err < 0)
 		return err;
 	pci_set_master(pci);
 
 	/* Allocate chip if needed */
-	if (!*rchip) {
-		chip = kzalloc(sizeof(*chip), GFP_KERNEL);
-		if (!chip) {
-			pci_disable_device(pci);
-			return -ENOMEM;
-		}
-		dev_dbg(card->dev, "chip=%p\n", chip);
-		spin_lock_init(&chip->lock);
-		chip->card = card;
-		chip->pci = pci;
-		chip->irq = -1;
-		chip->opencount = 0;
-		mutex_init(&chip->mode_mutex);
-		chip->can_set_rate = 1;
-	} else {
-		/* If this was called from the resume function, chip is
-		 * already allocated and it contains current card settings.
-		 */
-		chip = *rchip;
-	}
+	spin_lock_init(&chip->lock);
+	chip->card = card;
+	chip->pci = pci;
+	chip->irq = -1;
+	chip->opencount = 0;
+	mutex_init(&chip->mode_mutex);
+	chip->can_set_rate = 1;
 
 	/* PCI resource allocation */
+	err = pci_request_regions(pci, ECHOCARD_NAME);
+	if (err < 0)
+		return err;
+
 	chip->dsp_registers_phys = pci_resource_start(pci, 0);
 	sz = pci_resource_len(pci, 0);
 	if (sz > PAGE_SIZE)
 		sz = PAGE_SIZE;		/* We map only the required part */
 
-	chip->iores = request_mem_region(chip->dsp_registers_phys, sz,
-					 ECHOCARD_NAME);
-	if (!chip->iores) {
-		dev_err(chip->card->dev, "cannot get memory region\n");
-		snd_echo_free(chip);
-		return -EBUSY;
-	}
-	chip->dsp_registers = ioremap(chip->dsp_registers_phys, sz);
+	chip->dsp_registers = devm_ioremap(&pci->dev, chip->dsp_registers_phys, sz);
 	if (!chip->dsp_registers) {
 		dev_err(chip->card->dev, "ioremap failed\n");
-		snd_echo_free(chip);
 		return -ENOMEM;
 	}
 
 	if (request_irq(pci->irq, snd_echo_interrupt, IRQF_SHARED,
 			KBUILD_MODNAME, chip)) {
 		dev_err(chip->card->dev, "cannot grab irq\n");
-		snd_echo_free(chip);
 		return -EBUSY;
 	}
 	chip->irq = pci->irq;
···
 	dev_dbg(card->dev, "pci=%p irq=%d subdev=%04x Init hardware...\n",
 		chip->pci, chip->irq, chip->pci->subsystem_device);
 
+	card->private_free = snd_echo_free;
+
 	/* Create the DSP comm page - this is the area of memory used for most
 	of the communication with the DSP, which accesses it via bus mastering */
-	if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, &chip->pci->dev,
-				sizeof(struct comm_page),
-				&chip->commpage_dma_buf) < 0) {
-		dev_err(chip->card->dev, "cannot allocate the comm page\n");
-		snd_echo_free(chip);
+	chip->commpage_dma_buf =
+		snd_devm_alloc_pages(&pci->dev, SNDRV_DMA_TYPE_DEV,
+				     sizeof(struct comm_page));
+	if (!chip->commpage_dma_buf)
 		return -ENOMEM;
-	}
-	chip->comm_page_phys = chip->commpage_dma_buf.addr;
-	chip->comm_page = (struct comm_page *)chip->commpage_dma_buf.area;
+	chip->comm_page_phys = chip->commpage_dma_buf->addr;
+	chip->comm_page = (struct comm_page *)chip->commpage_dma_buf->area;
 
 	err = init_hw(chip, chip->pci->device, chip->pci->subsystem_device);
 	if (err >= 0)
 		err = set_mixer_defaults(chip);
 	if (err < 0) {
 		dev_err(card->dev, "init_hw err=%d\n", err);
-		snd_echo_free(chip);
 		return err;
 	}
 
-	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
-	if (err < 0) {
-		snd_echo_free(chip);
-		return err;
-	}
-	*rchip = chip;
-	/* Init done ! */
 	return 0;
 }
-
-
 
 /* constructor */
 static int snd_echo_probe(struct pci_dev *pci,
···
 	}
 
 	i = 0;
-	err = snd_card_new(&pci->dev, index[dev], id[dev], THIS_MODULE,
-			   0, &card);
+	err = snd_devm_card_new(&pci->dev, index[dev], id[dev], THIS_MODULE,
+				sizeof(*chip), &card);
 	if (err < 0)
 		return err;
+	chip = card->private_data;
 
-	chip = NULL;	/* Tells snd_echo_create to allocate chip */
-	err = snd_echo_create(card, pci, &chip);
-	if (err < 0) {
-		snd_card_free(card);
+	err = snd_echo_create(card, pci);
+	if (err < 0)
 		return err;
-	}
 
 	strcpy(card->driver, "Echo_" ECHOCARD_NAME);
 	strcpy(card->shortname, chip->card_name);
···
 	err = snd_echo_new_pcm(chip);
 	if (err < 0) {
 		dev_err(chip->card->dev, "new pcm error %d\n", err);
-		snd_card_free(card);
 		return err;
 	}
 
···
 		err = snd_echo_midi_create(card, chip);
 		if (err < 0) {
 			dev_err(chip->card->dev, "new midi error %d\n", err);
-			snd_card_free(card);
 			return err;
 		}
 	}
···
 	snd_echo_vmixer.count = num_pipes_out(chip) * num_busses_out(chip);
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_vmixer, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 #ifdef ECHOCARD_HAS_LINE_OUT_GAIN
 	err = snd_ctl_add(chip->card,
 			  snd_ctl_new1(&snd_echo_line_output_gain, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 #endif
 #else /* ECHOCARD_HAS_VMIXER */
 	err = snd_ctl_add(chip->card,
 			  snd_ctl_new1(&snd_echo_pcm_output_gain, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 #endif /* ECHOCARD_HAS_VMIXER */
 
 #ifdef ECHOCARD_HAS_INPUT_GAIN
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_line_input_gain, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 #endif
 
 #ifdef ECHOCARD_HAS_INPUT_NOMINAL_LEVEL
 	if (!chip->hasnt_input_nominal_level) {
 		err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_intput_nominal_level, chip));
 		if (err < 0)
-			goto ctl_error;
+			return err;
 	}
 #endif
 
 #ifdef ECHOCARD_HAS_OUTPUT_NOMINAL_LEVEL
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_output_nominal_level, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 #endif
 
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_vumeters_switch, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_vumeters, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 
 #ifdef ECHOCARD_HAS_MONITOR
 	snd_echo_monitor_mixer.count = num_busses_in(chip) * num_busses_out(chip);
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_monitor_mixer, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 #endif
 
 #ifdef ECHOCARD_HAS_DIGITAL_IN_AUTOMUTE
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_automute_switch, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 #endif
 
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_channels_info, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 
 #ifdef ECHOCARD_HAS_DIGITAL_MODE_SWITCH
 	/* Creates a list of available digital modes */
···
 
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_digital_mode_switch, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 #endif /* ECHOCARD_HAS_DIGITAL_MODE_SWITCH */
 
 #ifdef ECHOCARD_HAS_EXTERNAL_CLOCK
···
 		chip->clock_src_ctl = snd_ctl_new1(&snd_echo_clock_source_switch, chip);
 		err = snd_ctl_add(chip->card, chip->clock_src_ctl);
 		if (err < 0)
-			goto ctl_error;
+			return err;
 	}
 #endif /* ECHOCARD_HAS_EXTERNAL_CLOCK */
 
 #ifdef ECHOCARD_HAS_DIGITAL_IO
 	err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_spdif_mode_switch, chip));
 	if (err < 0)
-		goto ctl_error;
+		return err;
 #endif
 
 #ifdef ECHOCARD_HAS_PHANTOM_POWER
 	if (chip->has_phantom_power) {
 		err = snd_ctl_add(chip->card, snd_ctl_new1(&snd_echo_phantom_power_switch, chip));
 		if (err < 0)
-			goto ctl_error;
+			return err;
 	}
 #endif
 
 	err = snd_card_register(card);
 	if (err < 0)
-		goto ctl_error;
+		return err;
 	dev_info(card->dev, "Card registered: %s\n", card->longname);
 
 	pci_set_drvdata(pci, chip);
 	dev++;
 	return 0;
-
-ctl_error:
-	dev_err(card->dev, "new control error %d\n", err);
-	snd_card_free(card);
-	return err;
 }
 
 
···
 #define SND_ECHO_PM_OPS	NULL
 #endif /* CONFIG_PM_SLEEP */
 
-
-static void snd_echo_remove(struct pci_dev *pci)
-{
-	struct echoaudio *chip;
-
-	chip = pci_get_drvdata(pci);
-	if (chip)
-		snd_card_free(chip->card);
-}
-
-
-
 /******************************************************************************
 	Everything starts and ends here
 ******************************************************************************/
···
 	.name = KBUILD_MODNAME,
 	.id_table = snd_echo_ids,
 	.probe = snd_echo_probe,
-	.remove = snd_echo_remove,
 	.driver = {
 		.pm = SND_ECHO_PM_OPS,
 	},

sound/pci/echoaudio/echoaudio.h

···
 	struct pci_dev *pci;
 	unsigned long dsp_registers_phys;
 	struct resource *iores;
-	struct snd_dma_buffer commpage_dma_buf;
+	struct snd_dma_buffer *commpage_dma_buf;
 	int irq;
 #ifdef ECHOCARD_HAS_MIDI
 	struct snd_rawmidi *rmidi;