diff options
Diffstat (limited to 'Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl')
| -rw-r--r-- | Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl | 592 |
1 files changed, 347 insertions, 245 deletions
diff --git a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl index 260334c98d9..4963d83d151 100644 --- a/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl +++ b/Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl @@ -18,8 +18,8 @@ </affiliation> </author> - <date>October 6, 2005</date> - <edition>0.3.5</edition> + <date>November 17, 2005</date> + <edition>0.3.6</edition> <abstract> <para> @@ -403,9 +403,8 @@ static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP; /* definition of the chip-specific record */ - typedef struct snd_mychip mychip_t; - struct snd_mychip { - snd_card_t *card; + struct mychip { + struct snd_card *card; // rest of implementation will be in the section // "PCI Resource Managements" }; @@ -413,7 +412,7 @@ /* chip-specific destructor * (see "PCI Resource Managements") */ - static int snd_mychip_free(mychip_t *chip) + static int snd_mychip_free(struct mychip *chip) { .... // will be implemented later... } @@ -421,22 +420,21 @@ /* component-destructor * (see "Management of Cards and Components") */ - static int snd_mychip_dev_free(snd_device_t *device) + static int snd_mychip_dev_free(struct snd_device *device) { - mychip_t *chip = device->device_data; - return snd_mychip_free(chip); + return snd_mychip_free(device->device_data); } /* chip-specific constructor * (see "Management of Cards and Components") */ - static int __devinit snd_mychip_create(snd_card_t *card, + static int __devinit snd_mychip_create(struct snd_card *card, struct pci_dev *pci, - mychip_t **rchip) + struct mychip **rchip) { - mychip_t *chip; + struct mychip *chip; int err; - static snd_device_ops_t ops = { + static struct snd_device_ops ops = { .dev_free = snd_mychip_dev_free, }; @@ -474,8 +472,8 @@ const struct pci_device_id *pci_id) { static int dev; - snd_card_t *card; - mychip_t *chip; + struct snd_card *card; + struct mychip *chip; int err; /* (1) */ @@ -582,7 +580,7 @@ <informalexample> <programlisting> <![CDATA[ - snd_card_t *card; + struct snd_card *card; .... card = snd_card_new(index[dev], id[dev], THIS_MODULE, 0); ]]> @@ -605,7 +603,7 @@ <informalexample> <programlisting> <![CDATA[ - mychip_t *chip; + struct mychip *chip; .... if ((err = snd_mychip_create(card, pci, &chip)) < 0) { snd_card_free(card); @@ -806,7 +804,7 @@ <informalexample> <programlisting> <![CDATA[ - snd_card_t *card; + struct snd_card *card; card = snd_card_new(index, id, module, extra_size); ]]> </programlisting> @@ -830,7 +828,7 @@ <para> After the card is created, you can attach the components (devices) to the card instance. On ALSA driver, a component is - represented as a <type>snd_device_t</type> object. + represented as a struct <structname>snd_device</structname> object. A component can be a PCM instance, a control interface, a raw MIDI interface, etc. Each of such instances has one component entry. @@ -891,14 +889,11 @@ The chip-specific information, e.g. the i/o port address, its resource pointer, or the irq number, is stored in the chip-specific record. - Usually, the chip-specific record is typedef'ed as - <type>xxx_t</type> like the following: <informalexample> <programlisting> <![CDATA[ - typedef struct snd_mychip mychip_t; - struct snd_mychip { + struct mychip { .... }; ]]> @@ -918,12 +913,12 @@ <informalexample> <programlisting> <![CDATA[ - card = snd_card_new(index[dev], id[dev], THIS_MODULE, sizeof(mychip_t)); + card = snd_card_new(index[dev], id[dev], THIS_MODULE, sizeof(struct mychip)); ]]> </programlisting> </informalexample> - whether <type>mychip_t</type> is the type of the chip record. + whether struct <structname>mychip</structname> is the type of the chip record. </para> <para> @@ -932,7 +927,7 @@ <informalexample> <programlisting> <![CDATA[ - mychip_t *chip = (mychip_t *)card->private_data; + struct mychip *chip = (struct mychip *)card->private_data; ]]> </programlisting> </informalexample> @@ -954,8 +949,8 @@ <informalexample> <programlisting> <![CDATA[ - snd_card_t *card; - mychip_t *chip; + struct snd_card *card; + struct mychip *chip; card = snd_card_new(index[dev], id[dev], THIS_MODULE, NULL); ..... chip = kzalloc(sizeof(*chip), GFP_KERNEL); @@ -971,8 +966,8 @@ <informalexample> <programlisting> <![CDATA[ - struct snd_mychip { - snd_card_t *card; + struct mychip { + struct snd_card *card; .... }; ]]> @@ -1000,7 +995,7 @@ <informalexample> <programlisting> <![CDATA[ - static snd_device_ops_t ops = { + static struct snd_device_ops ops = { .dev_free = snd_mychip_dev_free, }; .... @@ -1018,10 +1013,9 @@ <informalexample> <programlisting> <![CDATA[ - static int snd_mychip_dev_free(snd_device_t *device) + static int snd_mychip_dev_free(struct snd_device *device) { - mychip_t *chip = device->device_data; - return snd_mychip_free(chip); + return snd_mychip_free(device->device_data); } ]]> </programlisting> @@ -1087,15 +1081,15 @@ <title>PCI Resource Managements Example</title> <programlisting> <![CDATA[ - struct snd_mychip { - snd_card_t *card; + struct mychip { + struct snd_card *card; struct pci_dev *pci; unsigned long port; int irq; }; - static int snd_mychip_free(mychip_t *chip) + static int snd_mychip_free(struct mychip *chip) { /* disable hardware here if any */ .... // (not implemented in this document) @@ -1113,13 +1107,13 @@ } /* chip-specific constructor */ - static int __devinit snd_mychip_create(snd_card_t *card, + static int __devinit snd_mychip_create(struct snd_card *card, struct pci_dev *pci, - mychip_t **rchip) + struct mychip **rchip) { - mychip_t *chip; + struct mychip *chip; int err; - static snd_device_ops_t ops = { + static struct snd_device_ops ops = { .dev_free = snd_mychip_dev_free, }; @@ -1155,8 +1149,7 @@ } chip->port = pci_resource_start(pci, 0); if (request_irq(pci->irq, snd_mychip_interrupt, - SA_INTERRUPT|SA_SHIRQ, "My Chip", - (void *)chip)) { + SA_INTERRUPT|SA_SHIRQ, "My Chip", chip)) { printk(KERN_ERR "cannot grab irq %d\n", pci->irq); snd_mychip_free(chip); return -EBUSY; @@ -1268,14 +1261,14 @@ <para> Now assume that this PCI device has an I/O port with 8 bytes - and an interrupt. Then <type>mychip_t</type> will have the + and an interrupt. Then struct <structname>mychip</structname> will have the following fields: <informalexample> <programlisting> <![CDATA[ - struct snd_mychip { - snd_card_t *card; + struct mychip { + struct snd_card *card; unsigned long port; int irq; @@ -1330,8 +1323,7 @@ <programlisting> <![CDATA[ if (request_irq(pci->irq, snd_mychip_interrupt, - SA_INTERRUPT|SA_SHIRQ, "My Chip", - (void *)chip)) { + SA_INTERRUPT|SA_SHIRQ, "My Chip", chip)) { printk(KERN_ERR "cannot grab irq %d\n", pci->irq); snd_mychip_free(chip); return -EBUSY; @@ -1372,7 +1364,7 @@ static irqreturn_t snd_mychip_interrupt(int irq, void *dev_id, struct pt_regs *regs) { - mychip_t *chip = dev_id; + struct mychip *chip = dev_id; .... return IRQ_HANDLED; } @@ -1487,7 +1479,7 @@ <informalexample> <programlisting> <![CDATA[ - struct snd_mychip { + struct mychip { .... unsigned long iobase_phys; void __iomem *iobase_virt; @@ -1517,7 +1509,7 @@ <informalexample> <programlisting> <![CDATA[ - static int snd_mychip_free(mychip_t *chip) + static int snd_mychip_free(struct mychip *chip) { .... if (chip->iobase_virt) @@ -1537,7 +1529,7 @@ <title>Registration of Device Struct</title> <para> At some point, typically after calling <function>snd_device_new()</function>, - you need to register the <structname>struct device</structname> of the chip + you need to register the struct <structname>device</structname> of the chip you're handling for udev and co. ALSA provides a macro for compatibility with older kernels. Simply call like the following: <informalexample> @@ -1739,7 +1731,7 @@ .... /* hardware definition */ - static snd_pcm_hardware_t snd_mychip_playback_hw = { + static struct snd_pcm_hardware snd_mychip_playback_hw = { .info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER | @@ -1758,7 +1750,7 @@ }; /* hardware definition */ - static snd_pcm_hardware_t snd_mychip_capture_hw = { + static struct snd_pcm_hardware snd_mychip_capture_hw = { .info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER | @@ -1777,10 +1769,10 @@ }; /* open callback */ - static int snd_mychip_playback_open(snd_pcm_substream_t *substream) + static int snd_mychip_playback_open(struct snd_pcm_substream *substream) { - mychip_t *chip = snd_pcm_substream_chip(substream); - snd_pcm_runtime_t *runtime = substream->runtime; + struct mychip *chip = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; runtime->hw = snd_mychip_playback_hw; // more hardware-initialization will be done here @@ -1788,19 +1780,19 @@ } /* close callback */ - static int snd_mychip_playback_close(snd_pcm_substream_t *substream) + static int snd_mychip_playback_close(struct snd_pcm_substream *substream) { - mychip_t *chip = snd_pcm_substream_chip(substream); + struct mychip *chip = snd_pcm_substream_chip(substream); // the hardware-specific codes will be here return 0; } /* open callback */ - static int snd_mychip_capture_open(snd_pcm_substream_t *substream) + static int snd_mychip_capture_open(struct snd_pcm_substream *substream) { - mychip_t *chip = snd_pcm_substream_chip(substream); - snd_pcm_runtime_t *runtime = substream->runtime; + struct mychip *chip = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; runtime->hw = snd_mychip_capture_hw; // more hardware-initialization will be done here @@ -1808,33 +1800,33 @@ } /* close callback */ - static int snd_mychip_capture_close(snd_pcm_substream_t *substream) + static int snd_mychip_capture_close(struct snd_pcm_substream *substream) { - mychip_t *chip = snd_pcm_substream_chip(substream); + struct mychip *chip = snd_pcm_substream_chip(substream); // the hardware-specific codes will be here return 0; } /* hw_params callback */ - static int snd_mychip_pcm_hw_params(snd_pcm_substream_t *substream, - snd_pcm_hw_params_t * hw_params) + static int snd_mychip_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *hw_params) { return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params)); } /* hw_free callback */ - static int snd_mychip_pcm_hw_free(snd_pcm_substream_t *substream) + static int snd_mychip_pcm_hw_free(struct snd_pcm_substream *substream) { return snd_pcm_lib_free_pages(substream); } /* prepare callback */ - static int snd_mychip_pcm_prepare(snd_pcm_substream_t *substream) + static int snd_mychip_pcm_prepare(struct snd_pcm_substream *substream) { - mychip_t *chip = snd_pcm_substream_chip(substream); - snd_pcm_runtime_t *runtime = substream->runtime; + struct mychip *chip = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; /* set up the hardware with the current configuration * for example... @@ -1849,7 +1841,7 @@ } /* trigger callback */ - static int snd_mychip_pcm_trigger(snd_pcm_substream_t *substream, + static int snd_mychip_pcm_trigger(struct snd_pcm_substream *substream, int cmd) { switch (cmd) { @@ -1866,9 +1858,9 @@ /* pointer callback */ static snd_pcm_uframes_t - snd_mychip_pcm_pointer(snd_pcm_substream_t *substream) + snd_mychip_pcm_pointer(struct snd_pcm_substream *substream) { - mychip_t *chip = snd_pcm_substream_chip(substream); + struct mychip *chip = snd_pcm_substream_chip(substream); unsigned int current_ptr; /* get the current hardware pointer */ @@ -1877,7 +1869,7 @@ } /* operators */ - static snd_pcm_ops_t snd_mychip_playback_ops = { + static struct snd_pcm_ops snd_mychip_playback_ops = { .open = snd_mychip_playback_open, .close = snd_mychip_playback_close, .ioctl = snd_pcm_lib_ioctl, @@ -1889,7 +1881,7 @@ }; /* operators */ - static snd_pcm_ops_t snd_mychip_capture_ops = { + static struct snd_pcm_ops snd_mychip_capture_ops = { .open = snd_mychip_capture_open, .close = snd_mychip_capture_close, .ioctl = snd_pcm_lib_ioctl, @@ -1905,9 +1897,9 @@ */ /* create a pcm device */ - static int __devinit snd_mychip_new_pcm(mychip_t *chip) + static int __devinit snd_mychip_new_pcm(struct mychip *chip) { - snd_pcm_t *pcm; + struct snd_pcm *pcm; int err; if ((err = snd_pcm_new(chip->card, "My Chip", 0, 1, 1, @@ -1944,9 +1936,9 @@ <informalexample> <programlisting> <![CDATA[ - static int __devinit snd_mychip_new_pcm(mychip_t *chip) + static int __devinit snd_mychip_new_pcm(struct mychip *chip) { - snd_pcm_t *pcm; + struct snd_pcm *pcm; int err; if ((err = snd_pcm_new(chip->card, "My Chip", 0, 1, 1, @@ -1989,13 +1981,13 @@ specify more numbers, but they must be handled properly in open/close, etc. callbacks. When you need to know which substream you are referring to, then it can be obtained from - <type>snd_pcm_substream_t</type> data passed to each callback + struct <structname>snd_pcm_substream</structname> data passed to each callback as follows: <informalexample> <programlisting> <![CDATA[ - snd_pcm_substream_t *substream; + struct snd_pcm_substream *substream; int index = substream->number; ]]> </programlisting> @@ -2024,7 +2016,7 @@ <informalexample> <programlisting> <![CDATA[ - static snd_pcm_ops_t snd_mychip_playback_ops = { + static struct snd_pcm_ops snd_mychip_playback_ops = { .open = snd_mychip_pcm_open, .close = snd_mychip_pcm_close, .ioctl = snd_pcm_lib_ioctl, @@ -2102,18 +2094,18 @@ <title>PCM Instance with a Destructor</title> <programlisting> <![CDATA[ - static void mychip_pcm_free(snd_pcm_t *pcm) + static void mychip_pcm_free(struct snd_pcm *pcm) { - mychip_t *chip = snd_pcm_chip(pcm); + struct mychip *chip = snd_pcm_chip(pcm); /* free your own data */ kfree(chip->my_private_pcm_data); // do what you like else .... } - static int __devinit snd_mychip_new_pcm(mychip_t *chip) + static int __devinit snd_mychip_new_pcm(struct mychip *chip) { - snd_pcm_t *pcm; + struct snd_pcm *pcm; .... /* allocate your own data */ chip->my_private_pcm_data = kmalloc(...); @@ -2149,7 +2141,7 @@ <![CDATA[ struct _snd_pcm_runtime { /* -- Status -- */ - snd_pcm_substream_t *trigger_master; + struct snd_pcm_substream *trigger_master; snd_timestamp_t trigger_tstamp; /* trigger timestamp */ int overrange; snd_pcm_uframes_t avail_max; @@ -2192,8 +2184,8 @@ struct _snd_pcm_runtime { snd_pcm_sync_id_t sync; /* hardware synchronization ID */ /* -- mmap -- */ - volatile snd_pcm_mmap_status_t *status; - volatile snd_pcm_mmap_control_t *control; + volatile struct snd_pcm_mmap_status *status; + volatile struct snd_pcm_mmap_control *control; atomic_t mmap_count; /* -- locking / scheduling -- */ @@ -2204,15 +2196,15 @@ struct _snd_pcm_runtime { /* -- private section -- */ void *private_data; - void (*private_free)(snd_pcm_runtime_t *runtime); + void (*private_free)(struct snd_pcm_runtime *runtime); /* -- hardware description -- */ - snd_pcm_hardware_t hw; - snd_pcm_hw_constraints_t hw_constraints; + struct snd_pcm_hardware hw; + struct snd_pcm_hw_constraints hw_constraints; /* -- interrupt callbacks -- */ - void (*transfer_ack_begin)(snd_pcm_substream_t *substream); - void (*transfer_ack_end)(snd_pcm_substream_t *substream); + void (*transfer_ack_begin)(struct snd_pcm_substream *substream); + void (*transfer_ack_end)(struct snd_pcm_substream *substream); /* -- timer -- */ unsigned int timer_resolution; /* timer resolution */ @@ -2226,7 +2218,7 @@ struct _snd_pcm_runtime { #if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE) /* -- OSS things -- */ - snd_pcm_oss_runtime_t oss; + struct snd_pcm_oss_runtime oss; #endif }; ]]> @@ -2252,7 +2244,7 @@ struct _snd_pcm_runtime { <section id="pcm-interface-runtime-hw"> <title>Hardware Description</title> <para> - The hardware descriptor (<type>snd_pcm_hardware_t</type>) + The hardware descriptor (struct <structname>snd_pcm_hardware</structname>) contains the definitions of the fundamental hardware configuration. Above all, you'll need to define this in <link linkend="pcm-interface-operators-open-callback"><citetitle> @@ -2267,7 +2259,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - snd_pcm_runtime_t *runtime = substream->runtime; + struct snd_pcm_runtime *runtime = substream->runtime; ... runtime->hw = snd_mychip_playback_hw; /* common definition */ if (chip->model == VERY_OLD_ONE) @@ -2282,7 +2274,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static snd_pcm_hardware_t snd_mychip_playback_hw = { + static struct snd_pcm_hardware snd_mychip_playback_hw = { .info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER | @@ -2337,9 +2329,14 @@ struct _snd_pcm_runtime { <constant>PAUSE</constant> bit means that the pcm supports the <quote>pause</quote> operation, while the <constant>RESUME</constant> bit means that the pcm supports - the <quote>suspend/resume</quote> operation. If these flags - are set, the <structfield>trigger</structfield> callback below - must handle the corresponding commands. + the full <quote>suspend/resume</quote> operation. + If <constant>PAUSE</constant> flag is set, + the <structfield>trigger</structfield> callback below + must handle the corresponding (pause push/release) commands. + The suspend/resume trigger commands can be defined even without + <constant>RESUME</constant> flag. See <link + linkend="power-management"><citetitle> + Power Management</citetitle></link> section for details. </para> <para> @@ -2512,7 +2509,7 @@ struct _snd_pcm_runtime { <title>Running Status</title> <para> The running status can be referred via <constant>runtime->status</constant>. - This is the pointer to <type>snd_pcm_mmap_status_t</type> + This is the pointer to struct <structname>snd_pcm_mmap_status</structname> record. For example, you can get the current DMA hardware pointer via <constant>runtime->status->hw_ptr</constant>. </para> @@ -2520,7 +2517,7 @@ struct _snd_pcm_runtime { <para> The DMA application pointer can be referred via <constant>runtime->control</constant>, which points - <type>snd_pcm_mmap_control_t</type> record. + struct <structname>snd_pcm_mmap_control</structname> record. However, accessing directly to this value is not recommended. </para> </section> @@ -2542,9 +2539,9 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_open(snd_pcm_substream_t *substream) + static int snd_xxx_open(struct snd_pcm_substream *substream) { - my_pcm_data_t *data; + struct my_pcm_data *data; .... data = kmalloc(sizeof(*data), GFP_KERNEL); substream->runtime->private_data = data; @@ -2586,7 +2583,7 @@ struct _snd_pcm_runtime { <para> The callback function takes at least the argument with - <type>snd_pcm_substream_t</type> pointer. For retrieving the + <structname>snd_pcm_substream</structname> pointer. For retrieving the chip record from the given substream instance, you can use the following macro. @@ -2594,7 +2591,7 @@ struct _snd_pcm_runtime { <programlisting> <![CDATA[ int xxx() { - mychip_t *chip = snd_pcm_substream_chip(substream); + struct mychip *chip = snd_pcm_substream_chip(substream); .... } ]]> @@ -2616,7 +2613,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_open(snd_pcm_substream_t *substream); + static int snd_xxx_open(struct snd_pcm_substream *substream); ]]> </programlisting> </informalexample> @@ -2631,10 +2628,10 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_open(snd_pcm_substream_t *substream) + static int snd_xxx_open(struct snd_pcm_substream *substream) { - mychip_t *chip = snd_pcm_substream_chip(substream); - snd_pcm_runtime_t *runtime = substream->runtime; + struct mychip *chip = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; runtime->hw = snd_mychip_playback_hw; return 0; @@ -2667,7 +2664,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_close(snd_pcm_substream_t *substream); + static int snd_xxx_close(struct snd_pcm_substream *substream); ]]> </programlisting> </informalexample> @@ -2682,7 +2679,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_close(snd_pcm_substream_t *substream) + static int snd_xxx_close(struct snd_pcm_substream *substream) { .... kfree(substream->runtime->private_data); @@ -2709,8 +2706,8 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_hw_params(snd_pcm_substream_t * substream, - snd_pcm_hw_params_t * hw_params); + static int snd_xxx_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *hw_params); ]]> </programlisting> </informalexample> @@ -2785,7 +2782,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_hw_free(snd_pcm_substream_t * substream); + static int snd_xxx_hw_free(struct snd_pcm_substream *substream); ]]> </programlisting> </informalexample> @@ -2820,7 +2817,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_prepare(snd_pcm_substream_t * substream); + static int snd_xxx_prepare(struct snd_pcm_substream *substream); ]]> </programlisting> </informalexample> @@ -2869,7 +2866,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_trigger(snd_pcm_substream_t * substream, int cmd); + static int snd_xxx_trigger(struct snd_pcm_substream *substream, int cmd); ]]> </programlisting> </informalexample> @@ -2911,8 +2908,8 @@ struct _snd_pcm_runtime { </para> <para> - When the pcm supports the suspend/resume operation - (i.e. <constant>SNDRV_PCM_INFO_RESUME</constant> flag is set), + When the pcm supports the suspend/resume operation, + regardless of full or partial suspend/resume support, <constant>SUSPEND</constant> and <constant>RESUME</constant> commands must be handled, too. These commands are issued when the power-management status is @@ -2921,6 +2918,8 @@ struct _snd_pcm_runtime { do suspend and resume of the pcm substream, and usually, they are identical with <constant>STOP</constant> and <constant>START</constant> commands, respectively. + See <link linkend="power-management"><citetitle> + Power Management</citetitle></link> section for details. </para> <para> @@ -2939,7 +2938,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static snd_pcm_uframes_t snd_xxx_pointer(snd_pcm_substream_t * substream) + static snd_pcm_uframes_t snd_xxx_pointer(struct snd_pcm_substream *substream) ]]> </programlisting> </informalexample> @@ -3067,7 +3066,7 @@ struct _snd_pcm_runtime { static irqreturn_t snd_mychip_interrupt(int irq, void *dev_id, struct pt_regs *regs) { - mychip_t *chip = dev_id; + struct mychip *chip = dev_id; spin_lock(&chip->lock); .... if (pcm_irq_invoked(chip)) { @@ -3111,7 +3110,7 @@ struct _snd_pcm_runtime { static irqreturn_t snd_mychip_interrupt(int irq, void *dev_id, struct pt_regs *regs) { - mychip_t *chip = dev_id; + struct mychip *chip = dev_id; spin_lock(&chip->lock); .... if (pcm_irq_invoked(chip)) { @@ -3221,13 +3220,13 @@ struct _snd_pcm_runtime { <![CDATA[ static unsigned int rates[] = {4000, 10000, 22050, 44100}; - static snd_pcm_hw_constraint_list_t constraints_rates = { + static struct snd_pcm_hw_constraint_list constraints_rates = { .count = ARRAY_SIZE(rates), .list = rates, .mask = 0, }; - static int snd_mychip_pcm_open(snd_pcm_substream_t *substream) + static int snd_mychip_pcm_open(struct snd_pcm_substream *substream) { int err; .... @@ -3249,19 +3248,20 @@ struct _snd_pcm_runtime { You can even define your own constraint rules. For example, let's suppose my_chip can manage a substream of 1 channel if and only if the format is S16_LE, otherwise it supports any format - specified in the <type>snd_pcm_hardware_t</type> stucture (or in any + specified in the <structname>snd_pcm_hardware</structname> stucture (or in any other constraint_list). You can build a rule like this: <example> <title>Example of Hardware Constraints for Channels</title> <programlisting> <![CDATA[ - static int hw_rule_format_by_channels(snd_pcm_hw_params_t *params, - snd_pcm_hw_rule_t *rule) + static int hw_rule_format_by_channels(struct snd_pcm_hw_params *params, + struct snd_pcm_hw_rule *rule) { - snd_interval_t *c = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS); - snd_mask_t *f = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT); - snd_mask_t fmt; + struct snd_interval *c = hw_param_interval(params, + SNDRV_PCM_HW_PARAM_CHANNELS); + struct snd_mask *f = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT); + struct snd_mask fmt; snd_mask_any(&fmt); /* Init the struct */ if (c->min < 2) { @@ -3298,12 +3298,13 @@ struct _snd_pcm_runtime { <title>Example of Hardware Constraints for Channels</title> <programlisting> <![CDATA[ - static int hw_rule_channels_by_format(snd_pcm_hw_params_t *params, - snd_pcm_hw_rule_t *rule) + static int hw_rule_channels_by_format(struct snd_pcm_hw_params *params, + struct snd_pcm_hw_rule *rule) { - snd_interval_t *c = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS); - snd_mask_t *f = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT); - snd_interval_t ch; + struct snd_interval *c = hw_param_interval(params, + SNDRV_PCM_HW_PARAM_CHANNELS); + struct snd_mask *f = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT); + struct snd_interval ch; snd_interval_any(&ch); if (f->bits[0] == SNDRV_PCM_FMTBIT_S16_LE) { @@ -3376,13 +3377,13 @@ struct _snd_pcm_runtime { callbacks: <structfield>info</structfield>, <structfield>get</structfield> and <structfield>put</structfield>. Then, define a - <type>snd_kcontrol_new_t</type> record, such as: + struct <structname>snd_kcontrol_new</structname> record, such as: <example> <title>Definition of a Control</title> <programlisting> <![CDATA[ - static snd_kcontrol_new_t my_control __devinitdata = { + static struct snd_kcontrol_new my_control __devinitdata = { .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = "PCM Playback Switch", .index = 0, @@ -3599,7 +3600,7 @@ struct _snd_pcm_runtime { <para> The <structfield>info</structfield> callback is used to get the detailed information of this control. This must store the - values of the given <type>snd_ctl_elem_info_t</type> + values of the given struct <structname>snd_ctl_elem_info</structname> object. For example, for a boolean control with a single element will be: @@ -3607,8 +3608,8 @@ struct _snd_pcm_runtime { <title>Example of info callback</title> <programlisting> <![CDATA[ - static int snd_myctl_info(snd_kcontrol_t *kcontrol, - snd_ctl_elem_info_t *uinfo) + static int snd_myctl_info(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_info *uinfo) { uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN; uinfo->count = 1; @@ -3642,8 +3643,8 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_myctl_info(snd_kcontrol_t *kcontrol, - snd_ctl_elem_info_t *uinfo) + static int snd_myctl_info(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_info *uinfo) { static char *texts[4] = { "First", "Second", "Third", "Fourth" @@ -3678,10 +3679,10 @@ struct _snd_pcm_runtime { <title>Example of get callback</title> <programlisting> <![CDATA[ - static int snd_myctl_get(snd_kcontrol_t *kcontrol, - snd_ctl_elem_value_t *ucontrol) + static int snd_myctl_get(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) { - mychip_t *chip = snd_kcontrol_chip(kcontrol); + struct mychip *chip = snd_kcontrol_chip(kcontrol); ucontrol->value.integer.value[0] = get_some_value(chip); return 0; } @@ -3717,8 +3718,8 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_sbmixer_get_single(snd_kcontrol_t *kcontrol, - snd_ctl_elem_value_t *ucontrol) + static int snd_sbmixer_get_single(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) { int reg = kcontrol->private_value & 0xff; int shift = (kcontrol->private_value >> 16) & 0xff; @@ -3754,10 +3755,10 @@ struct _snd_pcm_runtime { <title>Example of put callback</title> <programlisting> <![CDATA[ - static int snd_myctl_put(snd_kcontrol_t *kcontrol, - snd_ctl_elem_value_t *ucontrol) + static int snd_myctl_put(struct snd_kcontrol *kcontrol, + struct snd_ctl_elem_value *ucontrol) { - mychip_t *chip = snd_kcontrol_chip(kcontrol); + struct mychip *chip = snd_kcontrol_chip(kcontrol); int changed = 0; if (chip->current_value != ucontrol->value.integer.value[0]) { @@ -3814,7 +3815,7 @@ struct _snd_pcm_runtime { </informalexample> where <parameter>my_control</parameter> is the - <type>snd_kcontrol_new_t</type> object defined above, and chip + struct <structname>snd_kcontrol_new</structname> object defined above, and chip is the object pointer to be passed to kcontrol->private_data which can be referred in callbacks. @@ -3822,7 +3823,7 @@ struct _snd_pcm_runtime { <para> <function>snd_ctl_new1()</function> allocates a new - <type>snd_kcontrol_t</type> instance (that's why the definition + <structname>snd_kcontrol</structname> instance (that's why the definition of <parameter>my_control</parameter> can be with <parameter>__devinitdata</parameter> prefix), and <function>snd_ctl_add</function> assigns the given @@ -3849,7 +3850,7 @@ struct _snd_pcm_runtime { control id pointer for the notification. The event-mask specifies the types of notification, for example, in the above example, the change of control values is notified. - The id pointer is the pointer of <type>snd_ctl_elem_id_t</type> + The id pointer is the pointer of struct <structname>snd_ctl_elem_id</structname> to be notified. You can find some examples in <filename>es1938.c</filename> or <filename>es1968.c</filename> for hardware volume interrupts. @@ -3882,35 +3883,35 @@ struct _snd_pcm_runtime { <title>Example of AC97 Interface</title> <programlisting> <![CDATA[ - struct snd_mychip { + struct mychip { .... - ac97_t *ac97; + struct snd_ac97 *ac97; .... }; - static unsigned short snd_mychip_ac97_read(ac97_t *ac97, + static unsigned short snd_mychip_ac97_read(struct snd_ac97 *ac97, unsigned short reg) { - mychip_t *chip = ac97->private_data; + struct mychip *chip = ac97->private_data; .... // read a register value here from the codec return the_register_value; } - static void snd_mychip_ac97_write(ac97_t *ac97, + static void snd_mychip_ac97_write(struct snd_ac97 *ac97, unsigned short reg, unsigned short val) { - mychip_t *chip = ac97->private_data; + struct mychip *chip = ac97->private_data; .... // write the given register value to the codec } - static int snd_mychip_ac97(mychip_t *chip) + static int snd_mychip_ac97(struct mychip *chip) { - ac97_bus_t *bus; - ac97_template_t ac97; + struct snd_ac97_bus *bus; + struct snd_ac97_template ac97; int err; - static ac97_bus_ops_t ops = { + static struct snd_ac97_bus_ops ops = { .write = snd_mychip_ac97_write, .read = snd_mychip_ac97_read, }; @@ -3937,8 +3938,8 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - ac97_bus_t *bus; - static ac97_bus_ops_t ops = { + struct snd_ac97_bus *bus; + static struct snd_ac97_bus_ops ops = { .write = snd_mychip_ac97_write, .read = snd_mychip_ac97_read, }; @@ -3952,13 +3953,14 @@ struct _snd_pcm_runtime { </para> <para> - And then call <function>snd_ac97_mixer()</function> with an <type>ac97_template_t</type> + And then call <function>snd_ac97_mixer()</function> with an + struct <structname>snd_ac97_template</structname> record together with the bus pointer created above. <informalexample> <programlisting> <![CDATA[ - ac97_template_t ac97; + struct snd_ac97_template ac97; int err; memset(&ac97, 0, sizeof(ac97)); @@ -3995,10 +3997,10 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static unsigned short snd_mychip_ac97_read(ac97_t *ac97, + static unsigned short snd_mychip_ac97_read(struct snd_ac97 *ac97, unsigned short reg) { - mychip_t *chip = ac97->private_data; + struct mychip *chip = ac97->private_data; .... return the_register_value; } @@ -4016,7 +4018,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static void snd_mychip_ac97_write(ac97_t *ac97, + static void snd_mychip_ac97_write(struct snd_ac97 *ac97, unsigned short reg, unsigned short val) ]]> </programlisting> @@ -4163,7 +4165,7 @@ struct _snd_pcm_runtime { <title>Multiple Codecs</title> <para> When there are several codecs on the same card, you need to - call <function>snd_ac97_new()</function> multiple times with + call <function>snd_ac97_mixer()</function> multiple times with ac97.num=1 or greater. The <structfield>num</structfield> field specifies the codec number. @@ -4212,7 +4214,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - snd_rawmidi_t *rmidi; + struct snd_rawmidi *rmidi; snd_mpu401_uart_new(card, 0, MPU401_HW_MPU401, port, integrated, irq, irq_flags, &rmidi); ]]> @@ -4253,17 +4255,17 @@ struct _snd_pcm_runtime { Usually, the port address corresponds to the command port and port + 1 corresponds to the data port. If not, you may change the <structfield>cport</structfield> field of - <type>mpu401_t</type> manually - afterward. However, <type>mpu401_t</type> pointer is not + struct <structname>snd_mpu401</structname> manually + afterward. However, <structname>snd_mpu401</structname> pointer is not returned explicitly by <function>snd_mpu401_uart_new()</function>. You need to cast rmidi->private_data to - <type>mpu401_t</type> explicitly, + <structname>snd_mpu401</structname> explicitly, <informalexample> <programlisting> <![CDATA[ - mpu401_t *mpu; + struct snd_mpu401 *mpu; mpu = rmidi->private_data; ]]> </programlisting> @@ -4359,7 +4361,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - snd_rawmidi_t *rmidi; + struct snd_rawmidi *rmidi; err = snd_rawmidi_new(chip->card, "MyMIDI", 0, outs, ins, &rmidi); if (err < 0) return err; @@ -4419,7 +4421,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static snd_rawmidi_ops_t snd_mymidi_output_ops = { + static struct snd_rawmidi_ops snd_mymidi_output_ops = { .open = snd_mymidi_output_open, .close = snd_mymidi_output_close, .trigger = snd_mymidi_output_trigger, @@ -4439,9 +4441,9 @@ struct _snd_pcm_runtime { <programlisting> <![CDATA[ struct list_head *list; - snd_rawmidi_substream_t *substream; + struct snd_rawmidi_substream *substream; list_for_each(list, &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams) { - substream = list_entry(list, snd_rawmidi_substream_t, list); + substream = list_entry(list, struct snd_rawmidi_substream, list); sprintf(substream->name, "My MIDI Port %d", substream->number + 1); } /* same for SNDRV_RAWMIDI_STREAM_INPUT */ @@ -4463,12 +4465,12 @@ struct _snd_pcm_runtime { <para> If there is more than one port, your callbacks can determine the - port index from the snd_rawmidi_substream_t data passed to each + port index from the struct snd_rawmidi_substream data passed to each callback: <informalexample> <programlisting> <![CDATA[ - snd_rawmidi_substream_t *substream; + struct snd_rawmidi_substream *substream; int index = substream->number; ]]> </programlisting> @@ -4481,7 +4483,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_open(snd_rawmidi_substream_t *substream); + static int snd_xxx_open(struct snd_rawmidi_substream *substream); ]]> </programlisting> </informalexample> @@ -4499,7 +4501,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int snd_xxx_close(snd_rawmidi_substream_t *substream); + static int snd_xxx_close(struct snd_rawmidi_substream *substream); ]]> </programlisting> </informalexample> @@ -4522,7 +4524,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static void snd_xxx_output_trigger(snd_rawmidi_substream_t *substream, int up); + static void snd_xxx_output_trigger(struct snd_rawmidi_substream *substream, int up); ]]> </programlisting> </informalexample> @@ -4547,7 +4549,7 @@ struct _snd_pcm_runtime { <![CDATA[ unsigned char data; while (snd_rawmidi_transmit_peek(substream, &data, 1) == 1) { - if (mychip_try_to_transmit(data)) + if (snd_mychip_try_to_transmit(data)) snd_rawmidi_transmit_ack(substream, 1); else break; /* hardware FIFO full */ @@ -4564,11 +4566,11 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - while (mychip_transmit_possible()) { + while (snd_mychip_transmit_possible()) { unsigned char data; if (snd_rawmidi_transmit(substream, &data, 1) != 1) break; /* no more data */ - mychip_transmit(data); + snd_mychip_transmit(data); } ]]> </programlisting> @@ -4603,7 +4605,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static void snd_xxx_input_trigger(snd_rawmidi_substream_t *substream, int up); + static void snd_xxx_input_trigger(struct snd_rawmidi_substream *substream, int up); ]]> </programlisting> </informalexample> @@ -4647,7 +4649,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static void snd_xxx_drain(snd_rawmidi_substream_t *substream); + static void snd_xxx_drain(struct snd_rawmidi_substream *substream); ]]> </programlisting> </informalexample> @@ -4661,7 +4663,7 @@ struct _snd_pcm_runtime { <para> This callback is optional. If you do not set - <structfield>drain</structfield> in the snd_rawmidi_ops_t + <structfield>drain</structfield> in the struct snd_rawmidi_ops structure, ALSA will simply wait for 50 milliseconds instead. </para> @@ -4703,7 +4705,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - opl3_t *opl3; + struct snd_opl3 *opl3; snd_opl3_create(card, lport, rport, OPL3_HW_OPL3_XXX, integrated, &opl3); ]]> @@ -4736,7 +4738,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - opl3_t *opl3; + struct snd_opl3 *opl3; snd_opl3_new(card, OPL3_HW_OPL3_XXX, &opl3); ]]> </programlisting> @@ -4767,7 +4769,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - snd_hwdep_t *opl3hwdep; + struct snd_hwdep *opl3hwdep; snd_opl3_hwdep_new(opl3, 0, 1, &opl3hwdep); ]]> </programlisting> @@ -4804,7 +4806,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - snd_hwdep_t *hw; + struct snd_hwdep *hw; snd_hwdep_new(card, "My HWDEP", 0, &hw); ]]> </programlisting> @@ -4823,7 +4825,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - mydata_t *p = kmalloc(sizeof(*p), GFP_KERNEL); + struct mydata *p = kmalloc(sizeof(*p), GFP_KERNEL); hw->private_data = p; hw->private_free = mydata_free; ]]> @@ -4835,9 +4837,9 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static void mydata_free(snd_hwdep_t *hw) + static void mydata_free(struct snd_hwdep *hw) { - mydata_t *p = hw->private_data; + struct mydata *p = hw->private_data; kfree(p); } ]]> @@ -5061,9 +5063,9 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int playback_copy(snd_pcm_substream_t *substream, int channel, + static int playback_copy(struct snd_pcm_substream *substream, int channel, snd_pcm_uframes_t pos, void *src, snd_pcm_uframes_t count); - static int capture_copy(snd_pcm_substream_t *substream, int channel, + static int capture_copy(struct snd_pcm_substream *substream, int channel, snd_pcm_uframes_t pos, void *dst, snd_pcm_uframes_t count); ]]> </programlisting> @@ -5144,7 +5146,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int silence(snd_pcm_substream_t *substream, int channel, + static int silence(struct snd_pcm_substream *substream, int channel, snd_pcm_uframes_t pos, snd_pcm_uframes_t count); ]]> </programlisting> @@ -5211,7 +5213,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - snd_pcm_sgbuf_t *sgbuf = (snd_pcm_sgbuf_t*)substream->dma_private; + struct snd_sg_buf *sgbuf = (struct snd_sg_buf_t*)substream->dma_private; ]]> </programlisting> </informalexample> @@ -5266,7 +5268,7 @@ struct _snd_pcm_runtime { #include <linux/vmalloc.h> /* get the physical page pointer on the given offset */ - static struct page *mychip_page(snd_pcm_substream_t *substream, + static struct page *mychip_page(struct snd_pcm_substream *substream, unsigned long offset) { void *pageptr = substream->runtime->dma_area + offset; @@ -5301,7 +5303,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - snd_info_entry_t *entry; + struct snd_info_entry *entry; int err = snd_card_proc_new(card, "my-file", &entry); ]]> </programlisting> @@ -5345,8 +5347,8 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static void my_proc_read(snd_info_entry_t *entry, - snd_info_buffer_t *buffer); + static void my_proc_read(struct snd_info_entry *entry, + struct snd_info_buffer *buffer); ]]> </programlisting> </informalexample> @@ -5361,10 +5363,10 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static void my_proc_read(snd_info_entry_t *entry, - snd_info_buffer_t *buffer) + static void my_proc_read(struct snd_info_entry *entry, + struct snd_info_buffer *buffer) { - chip_t *chip = entry->private_data; + struct my_chip *chip = entry->private_data; snd_iprintf(buffer, "This is my chip!\n"); snd_iprintf(buffer, "Port = %ld\n", chip->port); @@ -5453,7 +5455,7 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static long my_file_io_read(snd_info_entry_t *entry, + static long my_file_io_read(struct snd_info_entry *entry, void *file_private_data, struct file *file, char *buf, @@ -5488,22 +5490,60 @@ struct _snd_pcm_runtime { <constant>CONFIG_PM</constant>. </para> + <para> + If the driver supports the suspend/resume + <emphasis>fully</emphasis>, that is, the device can be + properly resumed to the status at the suspend is called, + you can set <constant>SNDRV_PCM_INFO_RESUME</constant> flag + to pcm info field. Usually, this is possible when the + registers of ths chip can be safely saved and restored to the + RAM. If this is set, the trigger callback is called with + <constant>SNDRV_PCM_TRIGGER_RESUME</constant> after resume + callback is finished. + </para> + + <para> + Even if the driver doesn't support PM fully but only the + partial suspend/resume is possible, it's still worthy to + implement suspend/resume callbacks. In such a case, applications + would reset the status by calling + <function>snd_pcm_prepare()</function> and restart the stream + appropriately. Hence, you can define suspend/resume callbacks + below but don't set <constant>SNDRV_PCM_INFO_RESUME</constant> + info flag to the PCM. + </para> + + <para> + Note that the trigger with SUSPEND can be always called when + <function>snd_pcm_suspend_all</function> is called, + regardless of <constant>SNDRV_PCM_INFO_RESUME</constant> flag. + The <constant>RESUME</constant> flag affects only the behavior + of <function>snd_pcm_resume()</function>. + (Thus, in theory, + <constant>SNDRV_PCM_TRIGGER_RESUME</constant> isn't needed + to be handled in the trigger callback when no + <constant>SNDRV_PCM_INFO_RESUME</constant> flag is set. But, + it's better to keep it for compatibility reason.) + </para> <para> - ALSA provides the common power-management layer. Each card driver - needs to have only low-level suspend and resume callbacks. + In the earlier version of ALSA drivers, a common + power-management layer was provided, but it has been removed. + The driver needs to define the suspend/resume hooks according to + the bus the device is assigned. In the case of PCI driver, the + callbacks look like below: <informalexample> <programlisting> <![CDATA[ #ifdef CONFIG_PM - static int snd_my_suspend(snd_card_t *card, pm_message_t state) + static int snd_my_suspend(struct pci_dev *pci, pm_message_t state) { - .... // do things for suspsend + .... /* do things for suspsend */ return 0; } - static int snd_my_resume(snd_card_t *card) + static int snd_my_resume(struct pci_dev *pci) { - .... // do things for suspsend + .... /* do things for suspsend */ return 0; } #endif @@ -5516,11 +5556,18 @@ struct _snd_pcm_runtime { The scheme of the real suspend job is as following. <orderedlist> - <listitem><para>Retrieve the chip data from pm_private_data field.</para></listitem> + <listitem><para>Retrieve the card and the chip data.</para></listitem> + <listitem><para>Call <function>snd_power_change_state()</function> with + <constant>SNDRV_CTL_POWER_D3hot</constant> to change the + power status.</para></listitem> <listitem><para>Call <function>snd_pcm_suspend_all()</function> to suspend the running PCM streams.</para></listitem> + <listitem><para>If AC97 codecs are used, call + <function>snd_ac97_resume()</function> for each codec.</para></listitem> <listitem><para>Save the register values if necessary.</para></listitem> <listitem><para>Stop the hardware if necessary.</para></listitem> - <listitem><para>Disable the PCI device by calling <function>pci_disable_device()</function>.</para></listitem> + <listitem><para>Disable the PCI device by calling + <function>pci_disable_device()</function>. Then, call + <function>pci_save_state()</function> at last.</para></listitem> </orderedlist> </para> @@ -5530,18 +5577,24 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static int mychip_suspend(snd_card_t *card, pm_message_t state) + static int mychip_suspend(strut pci_dev *pci, pm_message_t state) { /* (1) */ - mychip_t *chip = card->pm_private_data; + struct snd_card *card = pci_get_drvdata(pci); + struct mychip *chip = card->private_data; /* (2) */ - snd_pcm_suspend_all(chip->pcm); + snd_power_change_state(card, SNDRV_CTL_POWER_D3hot); /* (3) */ - snd_mychip_save_registers(chip); + snd_pcm_suspend_all(chip->pcm); /* (4) */ - snd_mychip_stop_hardware(chip); + snd_ac97_suspend(chip->ac97); /* (5) */ - pci_disable_device(chip->pci); + snd_mychip_save_registers(chip); + /* (6) */ + snd_mychip_stop_hardware(chip); + /* (7) */ + pci_disable_device(pci); + pci_save_state(pci); return 0; } ]]> @@ -5553,14 +5606,17 @@ struct _snd_pcm_runtime { The scheme of the real resume job is as following. <orderedlist> - <listitem><para>Retrieve the chip data from pm_private_data field.</para></listitem> - <listitem><para>Enable the pci device again by calling - <function>pci_enable_device()</function>.</para></listitem> + <listitem><para>Retrieve the card and the chip data.</para></listitem> + <listitem><para>Set up PCI. First, call <function>pci_restore_state()</function>. + Then enable the pci device again by calling <function>pci_enable_device()</function>. + Call <function>pci_set_master()</function> if necessary, too.</para></listitem> <listitem><para>Re-initialize the chip.</para></listitem> <listitem><para>Restore the saved registers if necessary.</para></listitem> <listitem><para>Resume the mixer, e.g. calling <function>snd_ac97_resume()</function>.</para></listitem> <listitem><para>Restart the hardware (if any).</para></listitem> + <listitem><para>Call <function>snd_power_change_state()</function> with + <constant>SNDRV_CTL_POWER_D0</constant> to notify the processes.</para></listitem> </orderedlist> </para> @@ -5570,12 +5626,15 @@ struct _snd_pcm_runtime { <informalexample> <programlisting> <![CDATA[ - static void mychip_resume(mychip_t *chip) + static int mychip_resume(struct pci_dev *pci) { /* (1) */ - mychip_t *chip = card->pm_private_data; + struct snd_card *card = pci_get_drvdata(pci); + struct mychip *chip = card->private_data; /* (2) */ - pci_enable_device(chip->pci); + pci_restore_state(pci); + pci_enable_device(pci); + pci_set_master(pci); /* (3) */ snd_mychip_reinit_chip(chip); /* (4) */ @@ -5584,6 +5643,8 @@ struct _snd_pcm_runtime { snd_ac97_resume(chip->ac97); /* (6) */ snd_mychip_restart_chip(chip); + /* (7) */ + snd_power_change_state(card, SNDRV_CTL_POWER_D0); return 0; } ]]> @@ -5592,8 +5653,23 @@ struct _snd_pcm_runtime { </para> <para> - OK, we have all callbacks now. Let's set up them now. In the - initialization of the card, add the following: + As shown in the above, it's better to save registers after + suspending the PCM operations via + <function>snd_pcm_suspend_all()</function> or + <function>snd_pcm_suspend()</function>. It means that the PCM + streams are already stoppped when the register snapshot is + taken. But, remind that you don't have to restart the PCM + stream in the resume callback. It'll be restarted via + trigger call with <constant>SNDRV_PCM_TRIGGER_RESUME</constant> + when necessary. + </para> + + <para> + OK, we have all callbacks now. Let's set them up. In the + initialization of the card, make sure that you can get the chip + data from the card instance, typically via + <structfield>private_data</structfield> field, in case you + created the chip data individually. <informalexample> <programlisting> @@ -5602,33 +5678,56 @@ struct _snd_pcm_runtime { const struct pci_device_id *pci_id) { .... - snd_card_t *card; - mychip_t *chip; + struct snd_card *card; + struct mychip *chip; .... - snd_card_set_pm_callback(card, snd_my_suspend, snd_my_resume, chip); + card = snd_card_new(index[dev], id[dev], THIS_MODULE, NULL); + .... + chip = kzalloc(sizeof(*chip), GFP_KERNEL); + .... + card->private_data = chip; + .... + } +]]> + </programlisting> + </informalexample> + + When you created the chip data with + <function>snd_card_new()</function>, it's anyway accessible + via <structfield>private_data</structfield> field. + + <informalexample> + <programlisting> +<![CDATA[ + static int __devinit snd_mychip_probe(struct pci_dev *pci, + const struct pci_device_id *pci_id) + { + .... + struct snd_card *card; + struct mychip *chip; + .... + card = snd_card_new(index[dev], id[dev], THIS_MODULE, + sizeof(struct mychip)); + .... + chip = card->private_data; .... } ]]> </programlisting> </informalexample> - Here you don't have to put ifdef CONFIG_PM around, since it's already - checked in the header and expanded to empty if not needed. </para> <para> - If you need a space for saving the registers, you'll need to - allocate the buffer for it here, too, since it would be fatal + If you need a space for saving the registers, allocate the + buffer for it here, too, since it would be fatal if you cannot allocate a memory in the suspend phase. The allocated buffer should be released in the corresponding destructor. </para> <para> - And next, set suspend/resume callbacks to the pci_driver, - This can be done by passing a macro SND_PCI_PM_CALLBACKS - in the pci_driver struct. This macro is expanded to the correct - (global) callbacks if CONFIG_PM is set. + And next, set suspend/resume callbacks to the pci_driver. <informalexample> <programlisting> @@ -5638,7 +5737,10 @@ struct _snd_pcm_runtime { .id_table = snd_my_ids, .probe = snd_my_probe, .remove = __devexit_p(snd_my_remove), - SND_PCI_PM_CALLBACKS + #ifdef CONFIG_PM + .suspend = snd_my_suspend, + .resume = snd_my_resume, + #endif }; ]]> </programlisting> |