diff options
Diffstat (limited to 'drivers/staging/bcm2835-audio/bcm2835.c')
| -rw-r--r-- | drivers/staging/bcm2835-audio/bcm2835.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/drivers/staging/bcm2835-audio/bcm2835.c b/drivers/staging/bcm2835-audio/bcm2835.c new file mode 100644 index 000000000000..3a5e528e0ec6 --- /dev/null +++ b/drivers/staging/bcm2835-audio/bcm2835.c @@ -0,0 +1,250 @@ +/***************************************************************************** + * Copyright 2011 Broadcom Corporation. All rights reserved. + * + * Unless you and Broadcom execute a separate written software license + * agreement governing use of this software, this software is licensed to you + * under the terms of the GNU General Public License version 2, available at + * http://www.broadcom.com/licenses/GPLv2.php (the "GPL"). + * + * Notwithstanding the above, under no circumstances may you combine this + * software in any way with any other Broadcom software provided under a + * license other than the GPL, without Broadcom's express prior written + * consent. + *****************************************************************************/ + +#include <linux/platform_device.h> + +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/of.h> + +#include "bcm2835.h" + +/* HACKY global pointers needed for successive probes to work : ssp + * But compared against the changes we will have to do in VC audio_ipc code + * to export 8 audio_ipc devices as a single IPC device and then monitor all + * four devices in a thread, this gets things done quickly and should be easier + * to debug if we run into issues + */ + +static struct snd_card *g_card; +static struct bcm2835_chip *g_chip; + +static int snd_bcm2835_free(struct bcm2835_chip *chip) +{ + kfree(chip); + return 0; +} + +/* component-destructor + * (see "Management of Cards and Components") + */ +static int snd_bcm2835_dev_free(struct snd_device *device) +{ + return snd_bcm2835_free(device->device_data); +} + +/* chip-specific constructor + * (see "Management of Cards and Components") + */ +static int snd_bcm2835_create(struct snd_card *card, + struct platform_device *pdev, + struct bcm2835_chip **rchip) +{ + struct bcm2835_chip *chip; + int err; + static struct snd_device_ops ops = { + .dev_free = snd_bcm2835_dev_free, + }; + + *rchip = NULL; + + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->card = card; + + err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops); + if (err < 0) { + snd_bcm2835_free(chip); + return err; + } + + *rchip = chip; + return 0; +} + +static int snd_bcm2835_alsa_probe_dt(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct bcm2835_chip *chip; + struct snd_card *card; + u32 numchans; + int err, i; + + err = of_property_read_u32(dev->of_node, "brcm,pwm-channels", + &numchans); + if (err) { + dev_err(dev, "Failed to get DT property 'brcm,pwm-channels'"); + return err; + } + + if (numchans == 0 || numchans > MAX_SUBSTREAMS) { + numchans = MAX_SUBSTREAMS; + dev_warn(dev, "Illegal 'brcm,pwm-channels' value, will use %u\n", + numchans); + } + + err = snd_card_new(&pdev->dev, -1, NULL, THIS_MODULE, 0, &card); + if (err) { + dev_err(dev, "Failed to create soundcard structure\n"); + return err; + } + + snd_card_set_dev(card, dev); + strcpy(card->driver, "bcm2835"); + strcpy(card->shortname, "bcm2835 ALSA"); + sprintf(card->longname, "%s", card->shortname); + + err = snd_bcm2835_create(card, pdev, &chip); + if (err < 0) { + dev_err(dev, "Failed to create bcm2835 chip\n"); + goto err_free; + } + + err = snd_bcm2835_new_pcm(chip); + if (err < 0) { + dev_err(dev, "Failed to create new bcm2835 pcm device\n"); + goto err_free; + } + + err = snd_bcm2835_new_spdif_pcm(chip); + if (err < 0) { + dev_err(dev, "Failed to create new bcm2835 spdif pcm device\n"); + goto err_free; + } + + err = snd_bcm2835_new_ctl(chip); + if (err < 0) { + dev_err(dev, "Failed to create new bcm2835 ctl\n"); + goto err_free; + } + + for (i = 0; i < numchans; i++) { + chip->avail_substreams |= (1 << i); + chip->pdev[i] = pdev; + } + + err = snd_card_register(card); + if (err) { + dev_err(dev, "Failed to register bcm2835 ALSA card\n"); + goto err_free; + } + + g_card = card; + g_chip = chip; + platform_set_drvdata(pdev, card); + audio_info("bcm2835 ALSA card created with %u channels\n", numchans); + + return 0; + +err_free: + snd_card_free(card); + + return err; +} + +static int snd_bcm2835_alsa_remove(struct platform_device *pdev) +{ + int idx; + void *drv_data; + + drv_data = platform_get_drvdata(pdev); + + if (drv_data == (void *)g_card) { + /* This is the card device */ + snd_card_free((struct snd_card *)drv_data); + g_card = NULL; + g_chip = NULL; + } else { + idx = (int)(long)drv_data; + if (g_card) { + BUG_ON(!g_chip); + /* We pass chip device numbers in audio ipc devices + * other than the one we registered our card with + */ + idx = (int)(long)drv_data; + BUG_ON(!idx || idx > MAX_SUBSTREAMS); + g_chip->avail_substreams &= ~(1 << idx); + /* There should be atleast one substream registered + * after we are done here, as it wil be removed when + * the *remove* is called for the card device + */ + BUG_ON(!g_chip->avail_substreams); + } + } + + platform_set_drvdata(pdev, NULL); + + return 0; +} + +#ifdef CONFIG_PM + +static int snd_bcm2835_alsa_suspend(struct platform_device *pdev, + pm_message_t state) +{ + return 0; +} + +static int snd_bcm2835_alsa_resume(struct platform_device *pdev) +{ + return 0; +} + +#endif + +static const struct of_device_id snd_bcm2835_of_match_table[] = { + { .compatible = "brcm,bcm2835-audio",}, + {}, +}; +MODULE_DEVICE_TABLE(of, snd_bcm2835_of_match_table); + +static struct platform_driver bcm2835_alsa0_driver = { + .probe = snd_bcm2835_alsa_probe_dt, + .remove = snd_bcm2835_alsa_remove, +#ifdef CONFIG_PM + .suspend = snd_bcm2835_alsa_suspend, + .resume = snd_bcm2835_alsa_resume, +#endif + .driver = { + .name = "bcm2835_AUD0", + .owner = THIS_MODULE, + .of_match_table = snd_bcm2835_of_match_table, + }, +}; + +static int bcm2835_alsa_device_init(void) +{ + int retval; + + retval = platform_driver_register(&bcm2835_alsa0_driver); + if (retval) + pr_err("Error registering bcm2835_alsa0_driver %d .\n", retval); + + return retval; +} + +static void bcm2835_alsa_device_exit(void) +{ + platform_driver_unregister(&bcm2835_alsa0_driver); +} + +late_initcall(bcm2835_alsa_device_init); +module_exit(bcm2835_alsa_device_exit); + +MODULE_AUTHOR("Dom Cobley"); +MODULE_DESCRIPTION("Alsa driver for BCM2835 chip"); +MODULE_LICENSE("GPL"); |