android_kernel_samsung_msm8976/sound/aoa/soundbus/i2sbus/i2sbus-core.c
Paul Mackerras 547ac2ae38 [ALSA] aoa i2sbus: Stop Apple i2s DMA gracefully
This fixes the problem of getting extra bytes inserted at the
beginning of a recording when using the Apple i2s interface and DBDMA
controller.  It turns out that we can't just abort the DMA; we have to
let it stop at the end of a command, and then wait for the S7 bit to
be set before turning off the DBDMA controller.  Doing that for
playback doesn't seem to be necessary, but doesn't hurt either.
We use the technique used by the Darwin driver: make each transfer
command branch to a stop command if the S0 status bit is set.  Thus we
can ask the DMA controller to stop at the end of the current command
by setting S0.
The interrupt routine now looks at and clears the status word of the
DBDMA command ring.  This is necessary so it can know when the DBDMA
controller has seen that S0 is set, and so when it should look for the
DBDMA controller being stopped and S7 being set.  This also ended up
simplifying the calculation in i2sbus_pcm_pointer.
Tested on a 15 inch albook.
[Addition by Johannes]
I modified this patch and added the suspend/resume bits to it to get my
powermac into a decent state when playing sound across suspend to disk
that has a different bitrate from what the firmware programs the
hardware to.
I also added the SNDRV_PCM_INFO_JOINT_DUPLEX flag because it seemed the
right thing to do and I was looking at the info stuff.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
2007-02-09 09:04:02 +01:00

452 lines
12 KiB
C

/*
* i2sbus driver
*
* Copyright 2006 Johannes Berg <johannes@sipsolutions.net>
*
* GPL v2, can be found in COPYING.
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <sound/driver.h>
#include <sound/core.h>
#include <asm/macio.h>
#include <asm/dbdma.h>
#include "../soundbus.h"
#include "i2sbus.h"
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
MODULE_DESCRIPTION("Apple Soundbus: I2S support");
/* for auto-loading, declare that we handle this weird
* string that macio puts into the relevant device */
MODULE_ALIAS("of:Ni2sTi2sC");
static int force;
module_param(force, int, 0444);
MODULE_PARM_DESC(force, "Force loading i2sbus even when"
" no layout-id property is present");
static struct of_device_id i2sbus_match[] = {
{ .name = "i2s" },
{ }
};
static int alloc_dbdma_descriptor_ring(struct i2sbus_dev *i2sdev,
struct dbdma_command_mem *r,
int numcmds)
{
/* one more for rounding, one for branch back, one for stop command */
r->size = (numcmds + 3) * sizeof(struct dbdma_cmd);
/* We use the PCI APIs for now until the generic one gets fixed
* enough or until we get some macio-specific versions
*/
r->space = dma_alloc_coherent(
&macio_get_pci_dev(i2sdev->macio)->dev,
r->size,
&r->bus_addr,
GFP_KERNEL);
if (!r->space) return -ENOMEM;
memset(r->space, 0, r->size);
r->cmds = (void*)DBDMA_ALIGN(r->space);
r->bus_cmd_start = r->bus_addr +
(dma_addr_t)((char*)r->cmds - (char*)r->space);
return 0;
}
static void free_dbdma_descriptor_ring(struct i2sbus_dev *i2sdev,
struct dbdma_command_mem *r)
{
if (!r->space) return;
dma_free_coherent(&macio_get_pci_dev(i2sdev->macio)->dev,
r->size, r->space, r->bus_addr);
}
static void i2sbus_release_dev(struct device *dev)
{
struct i2sbus_dev *i2sdev;
int i;
i2sdev = container_of(dev, struct i2sbus_dev, sound.ofdev.dev);
if (i2sdev->intfregs) iounmap(i2sdev->intfregs);
if (i2sdev->out.dbdma) iounmap(i2sdev->out.dbdma);
if (i2sdev->in.dbdma) iounmap(i2sdev->in.dbdma);
for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++)
if (i2sdev->allocated_resource[i])
release_and_free_resource(i2sdev->allocated_resource[i]);
free_dbdma_descriptor_ring(i2sdev, &i2sdev->out.dbdma_ring);
free_dbdma_descriptor_ring(i2sdev, &i2sdev->in.dbdma_ring);
for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++)
free_irq(i2sdev->interrupts[i], i2sdev);
i2sbus_control_remove_dev(i2sdev->control, i2sdev);
mutex_destroy(&i2sdev->lock);
kfree(i2sdev);
}
static irqreturn_t i2sbus_bus_intr(int irq, void *devid)
{
struct i2sbus_dev *dev = devid;
u32 intreg;
spin_lock(&dev->low_lock);
intreg = in_le32(&dev->intfregs->intr_ctl);
/* acknowledge interrupt reasons */
out_le32(&dev->intfregs->intr_ctl, intreg);
spin_unlock(&dev->low_lock);
return IRQ_HANDLED;
}
/*
* XXX FIXME: We test the layout_id's here to get the proper way of
* mapping in various registers, thanks to bugs in Apple device-trees.
* We could instead key off the machine model and the name of the i2s
* node (i2s-a). This we'll do when we move it all to macio_asic.c
* and have that export items for each sub-node too.
*/
static int i2sbus_get_and_fixup_rsrc(struct device_node *np, int index,
int layout, struct resource *res)
{
struct device_node *parent;
int pindex, rc = -ENXIO;
u32 *reg;
/* Machines with layout 76 and 36 (K2 based) have a weird device
* tree what we need to special case.
* Normal machines just fetch the resource from the i2s-X node.
* Darwin further divides normal machines into old and new layouts
* with a subtely different code path but that doesn't seem necessary
* in practice, they just bloated it. In addition, even on our K2
* case the i2s-modem node, if we ever want to handle it, uses the
* normal layout
*/
if (layout != 76 && layout != 36)
return of_address_to_resource(np, index, res);
parent = of_get_parent(np);
pindex = (index == aoa_resource_i2smmio) ? 0 : 1;
rc = of_address_to_resource(parent, pindex, res);
if (rc)
goto bail;
reg = (u32 *)get_property(np, "reg", NULL);
if (reg == NULL) {
rc = -ENXIO;
goto bail;
}
res->start += reg[index * 2];
res->end = res->start + reg[index * 2 + 1] - 1;
bail:
of_node_put(parent);
return rc;
}
/* FIXME: look at device node refcounting */
static int i2sbus_add_dev(struct macio_dev *macio,
struct i2sbus_control *control,
struct device_node *np)
{
struct i2sbus_dev *dev;
struct device_node *child = NULL, *sound = NULL;
struct resource *r;
int i, layout = 0, rlen;
static const char *rnames[] = { "i2sbus: %s (control)",
"i2sbus: %s (tx)",
"i2sbus: %s (rx)" };
static irq_handler_t ints[] = {
i2sbus_bus_intr,
i2sbus_tx_intr,
i2sbus_rx_intr
};
if (strlen(np->name) != 5)
return 0;
if (strncmp(np->name, "i2s-", 4))
return 0;
dev = kzalloc(sizeof(struct i2sbus_dev), GFP_KERNEL);
if (!dev)
return 0;
i = 0;
while ((child = of_get_next_child(np, child))) {
if (strcmp(child->name, "sound") == 0) {
i++;
sound = child;
}
}
if (i == 1) {
u32 *layout_id;
layout_id = (u32*) get_property(sound, "layout-id", NULL);
if (layout_id) {
layout = *layout_id;
snprintf(dev->sound.modalias, 32,
"sound-layout-%d", layout);
force = 1;
}
}
/* for the time being, until we can handle non-layout-id
* things in some fabric, refuse to attach if there is no
* layout-id property or we haven't been forced to attach.
* When there are two i2s busses and only one has a layout-id,
* then this depends on the order, but that isn't important
* either as the second one in that case is just a modem. */
if (!force) {
kfree(dev);
return -ENODEV;
}
mutex_init(&dev->lock);
spin_lock_init(&dev->low_lock);
dev->sound.ofdev.node = np;
dev->sound.ofdev.dma_mask = macio->ofdev.dma_mask;
dev->sound.ofdev.dev.dma_mask = &dev->sound.ofdev.dma_mask;
dev->sound.ofdev.dev.parent = &macio->ofdev.dev;
dev->sound.ofdev.dev.release = i2sbus_release_dev;
dev->sound.attach_codec = i2sbus_attach_codec;
dev->sound.detach_codec = i2sbus_detach_codec;
dev->sound.pcmid = -1;
dev->macio = macio;
dev->control = control;
dev->bus_number = np->name[4] - 'a';
INIT_LIST_HEAD(&dev->sound.codec_list);
for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++) {
dev->interrupts[i] = -1;
snprintf(dev->rnames[i], sizeof(dev->rnames[i]),
rnames[i], np->name);
}
for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++) {
int irq = irq_of_parse_and_map(np, i);
if (request_irq(irq, ints[i], 0, dev->rnames[i], dev))
goto err;
dev->interrupts[i] = irq;
}
/* Resource handling is problematic as some device-trees contain
* useless crap (ugh ugh ugh). We work around that here by calling
* specific functions for calculating the appropriate resources.
*
* This will all be moved to macio_asic.c at one point
*/
for (i = aoa_resource_i2smmio; i <= aoa_resource_rxdbdma; i++) {
if (i2sbus_get_and_fixup_rsrc(np,i,layout,&dev->resources[i]))
goto err;
/* If only we could use our resource dev->resources[i]...
* but request_resource doesn't know about parents and
* contained resources...
*/
dev->allocated_resource[i] =
request_mem_region(dev->resources[i].start,
dev->resources[i].end -
dev->resources[i].start + 1,
dev->rnames[i]);
if (!dev->allocated_resource[i]) {
printk(KERN_ERR "i2sbus: failed to claim resource %d!\n", i);
goto err;
}
}
r = &dev->resources[aoa_resource_i2smmio];
rlen = r->end - r->start + 1;
if (rlen < sizeof(struct i2s_interface_regs))
goto err;
dev->intfregs = ioremap(r->start, rlen);
r = &dev->resources[aoa_resource_txdbdma];
rlen = r->end - r->start + 1;
if (rlen < sizeof(struct dbdma_regs))
goto err;
dev->out.dbdma = ioremap(r->start, rlen);
r = &dev->resources[aoa_resource_rxdbdma];
rlen = r->end - r->start + 1;
if (rlen < sizeof(struct dbdma_regs))
goto err;
dev->in.dbdma = ioremap(r->start, rlen);
if (!dev->intfregs || !dev->out.dbdma || !dev->in.dbdma)
goto err;
if (alloc_dbdma_descriptor_ring(dev, &dev->out.dbdma_ring,
MAX_DBDMA_COMMANDS))
goto err;
if (alloc_dbdma_descriptor_ring(dev, &dev->in.dbdma_ring,
MAX_DBDMA_COMMANDS))
goto err;
if (i2sbus_control_add_dev(dev->control, dev)) {
printk(KERN_ERR "i2sbus: control layer didn't like bus\n");
goto err;
}
if (soundbus_add_one(&dev->sound)) {
printk(KERN_DEBUG "i2sbus: device registration error!\n");
goto err;
}
/* enable this cell */
i2sbus_control_cell(dev->control, dev, 1);
i2sbus_control_enable(dev->control, dev);
i2sbus_control_clock(dev->control, dev, 1);
return 1;
err:
for (i=0;i<3;i++)
if (dev->interrupts[i] != -1)
free_irq(dev->interrupts[i], dev);
free_dbdma_descriptor_ring(dev, &dev->out.dbdma_ring);
free_dbdma_descriptor_ring(dev, &dev->in.dbdma_ring);
if (dev->intfregs) iounmap(dev->intfregs);
if (dev->out.dbdma) iounmap(dev->out.dbdma);
if (dev->in.dbdma) iounmap(dev->in.dbdma);
for (i=0;i<3;i++)
if (dev->allocated_resource[i])
release_and_free_resource(dev->allocated_resource[i]);
mutex_destroy(&dev->lock);
kfree(dev);
return 0;
}
static int i2sbus_probe(struct macio_dev* dev, const struct of_device_id *match)
{
struct device_node *np = NULL;
int got = 0, err;
struct i2sbus_control *control = NULL;
err = i2sbus_control_init(dev, &control);
if (err)
return err;
if (!control) {
printk(KERN_ERR "i2sbus_control_init API breakage\n");
return -ENODEV;
}
while ((np = of_get_next_child(dev->ofdev.node, np))) {
if (device_is_compatible(np, "i2sbus") ||
device_is_compatible(np, "i2s-modem")) {
got += i2sbus_add_dev(dev, control, np);
}
}
if (!got) {
/* found none, clean up */
i2sbus_control_destroy(control);
return -ENODEV;
}
dev->ofdev.dev.driver_data = control;
return 0;
}
static int i2sbus_remove(struct macio_dev* dev)
{
struct i2sbus_control *control = dev->ofdev.dev.driver_data;
struct i2sbus_dev *i2sdev, *tmp;
list_for_each_entry_safe(i2sdev, tmp, &control->list, item)
soundbus_remove_one(&i2sdev->sound);
return 0;
}
#ifdef CONFIG_PM
static int i2sbus_suspend(struct macio_dev* dev, pm_message_t state)
{
struct i2sbus_control *control = dev->ofdev.dev.driver_data;
struct codec_info_item *cii;
struct i2sbus_dev* i2sdev;
int err, ret = 0;
list_for_each_entry(i2sdev, &control->list, item) {
/* Notify Alsa */
if (i2sdev->sound.pcm) {
/* Suspend PCM streams */
snd_pcm_suspend_all(i2sdev->sound.pcm);
}
/* Notify codecs */
list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
err = 0;
if (cii->codec->suspend)
err = cii->codec->suspend(cii, state);
if (err)
ret = err;
}
/* wait until streams are stopped */
i2sbus_wait_for_stop_both(i2sdev);
}
return ret;
}
static int i2sbus_resume(struct macio_dev* dev)
{
struct i2sbus_control *control = dev->ofdev.dev.driver_data;
struct codec_info_item *cii;
struct i2sbus_dev* i2sdev;
int err, ret = 0;
list_for_each_entry(i2sdev, &control->list, item) {
/* reset i2s bus format etc. */
i2sbus_pcm_prepare_both(i2sdev);
/* Notify codecs so they can re-initialize */
list_for_each_entry(cii, &i2sdev->sound.codec_list, list) {
err = 0;
if (cii->codec->resume)
err = cii->codec->resume(cii);
if (err)
ret = err;
}
}
return ret;
}
#endif /* CONFIG_PM */
static int i2sbus_shutdown(struct macio_dev* dev)
{
return 0;
}
static struct macio_driver i2sbus_drv = {
.name = "soundbus-i2s",
.owner = THIS_MODULE,
.match_table = i2sbus_match,
.probe = i2sbus_probe,
.remove = i2sbus_remove,
#ifdef CONFIG_PM
.suspend = i2sbus_suspend,
.resume = i2sbus_resume,
#endif
.shutdown = i2sbus_shutdown,
};
static int __init soundbus_i2sbus_init(void)
{
return macio_register_driver(&i2sbus_drv);
}
static void __exit soundbus_i2sbus_exit(void)
{
macio_unregister_driver(&i2sbus_drv);
}
module_init(soundbus_i2sbus_init);
module_exit(soundbus_i2sbus_exit);