Commit 7c7b680f authored by Vinod Koul's avatar Vinod Koul

Merge branch 'topic/univ_api' into for-linus

parents 5eec9438 020c62ae
......@@ -22,25 +22,14 @@ The slave DMA usage consists of following steps:
Channel allocation is slightly different in the slave DMA context,
client drivers typically need a channel from a particular DMA
controller only and even in some cases a specific channel is desired.
To request a channel dma_request_channel() API is used.
To request a channel dma_request_chan() API is used.
Interface:
struct dma_chan *dma_request_channel(dma_cap_mask_t mask,
dma_filter_fn filter_fn,
void *filter_param);
where dma_filter_fn is defined as:
typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);
The 'filter_fn' parameter is optional, but highly recommended for
slave and cyclic channels as they typically need to obtain a specific
DMA channel.
When the optional 'filter_fn' parameter is NULL, dma_request_channel()
simply returns the first channel that satisfies the capability mask.
Otherwise, the 'filter_fn' routine will be called once for each free
channel which has a capability in 'mask'. 'filter_fn' is expected to
return 'true' when the desired DMA channel is found.
struct dma_chan *dma_request_chan(struct device *dev, const char *name);
Which will find and return the 'name' DMA channel associated with the 'dev'
device. The association is done via DT, ACPI or board file based
dma_slave_map matching table.
A channel allocated via this interface is exclusive to the caller,
until dma_release_channel() is called.
......
......@@ -43,6 +43,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/init.h>
#include <linux/module.h>
......@@ -512,7 +513,7 @@ static struct dma_chan *private_candidate(const dma_cap_mask_t *mask,
{
struct dma_chan *chan;
if (!__dma_device_satisfies_mask(dev, mask)) {
if (mask && !__dma_device_satisfies_mask(dev, mask)) {
pr_debug("%s: wrong capabilities\n", __func__);
return NULL;
}
......@@ -543,6 +544,42 @@ static struct dma_chan *private_candidate(const dma_cap_mask_t *mask,
return NULL;
}
static struct dma_chan *find_candidate(struct dma_device *device,
const dma_cap_mask_t *mask,
dma_filter_fn fn, void *fn_param)
{
struct dma_chan *chan = private_candidate(mask, device, fn, fn_param);
int err;
if (chan) {
/* Found a suitable channel, try to grab, prep, and return it.
* We first set DMA_PRIVATE to disable balance_ref_count as this
* channel will not be published in the general-purpose
* allocator
*/
dma_cap_set(DMA_PRIVATE, device->cap_mask);
device->privatecnt++;
err = dma_chan_get(chan);
if (err) {
if (err == -ENODEV) {
pr_debug("%s: %s module removed\n", __func__,
dma_chan_name(chan));
list_del_rcu(&device->global_node);
} else
pr_debug("%s: failed to get %s: (%d)\n",
__func__, dma_chan_name(chan), err);
if (--device->privatecnt == 0)
dma_cap_clear(DMA_PRIVATE, device->cap_mask);
chan = ERR_PTR(err);
}
}
return chan ? chan : ERR_PTR(-EPROBE_DEFER);
}
/**
* dma_get_slave_channel - try to get specific channel exclusively
* @chan: target channel
......@@ -581,7 +618,6 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
{
dma_cap_mask_t mask;
struct dma_chan *chan;
int err;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
......@@ -589,23 +625,11 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
/* lock against __dma_request_channel */
mutex_lock(&dma_list_mutex);
chan = private_candidate(&mask, device, NULL, NULL);
if (chan) {
dma_cap_set(DMA_PRIVATE, device->cap_mask);
device->privatecnt++;
err = dma_chan_get(chan);
if (err) {
pr_debug("%s: failed to get %s: (%d)\n",
__func__, dma_chan_name(chan), err);
chan = NULL;
if (--device->privatecnt == 0)
dma_cap_clear(DMA_PRIVATE, device->cap_mask);
}
}
chan = find_candidate(device, &mask, NULL, NULL);
mutex_unlock(&dma_list_mutex);
return chan;
return IS_ERR(chan) ? NULL : chan;
}
EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
......@@ -622,36 +646,16 @@ struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
{
struct dma_device *device, *_d;
struct dma_chan *chan = NULL;
int err;
/* Find a channel */
mutex_lock(&dma_list_mutex);
list_for_each_entry_safe(device, _d, &dma_device_list, global_node) {
chan = private_candidate(mask, device, fn, fn_param);
if (chan) {
/* Found a suitable channel, try to grab, prep, and
* return it. We first set DMA_PRIVATE to disable
* balance_ref_count as this channel will not be
* published in the general-purpose allocator
*/
dma_cap_set(DMA_PRIVATE, device->cap_mask);
device->privatecnt++;
err = dma_chan_get(chan);
if (err == -ENODEV) {
pr_debug("%s: %s module removed\n",
__func__, dma_chan_name(chan));
list_del_rcu(&device->global_node);
} else if (err)
pr_debug("%s: failed to get %s: (%d)\n",
__func__, dma_chan_name(chan), err);
else
chan = find_candidate(device, mask, fn, fn_param);
if (!IS_ERR(chan))
break;
if (--device->privatecnt == 0)
dma_cap_clear(DMA_PRIVATE, device->cap_mask);
chan = NULL;
}
}
mutex_unlock(&dma_list_mutex);
pr_debug("%s: %s (%s)\n",
......@@ -663,27 +667,73 @@ struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
}
EXPORT_SYMBOL_GPL(__dma_request_channel);
static const struct dma_slave_map *dma_filter_match(struct dma_device *device,
const char *name,
struct device *dev)
{
int i;
if (!device->filter.mapcnt)
return NULL;
for (i = 0; i < device->filter.mapcnt; i++) {
const struct dma_slave_map *map = &device->filter.map[i];
if (!strcmp(map->devname, dev_name(dev)) &&
!strcmp(map->slave, name))
return map;
}
return NULL;
}
/**
* dma_request_slave_channel_reason - try to allocate an exclusive slave channel
* dma_request_chan - try to allocate an exclusive slave channel
* @dev: pointer to client device structure
* @name: slave channel name
*
* Returns pointer to appropriate DMA channel on success or an error pointer.
*/
struct dma_chan *dma_request_slave_channel_reason(struct device *dev,
const char *name)
struct dma_chan *dma_request_chan(struct device *dev, const char *name)
{
struct dma_device *d, *_d;
struct dma_chan *chan = NULL;
/* If device-tree is present get slave info from here */
if (dev->of_node)
return of_dma_request_slave_channel(dev->of_node, name);
chan = of_dma_request_slave_channel(dev->of_node, name);
/* If device was enumerated by ACPI get slave info from here */
if (ACPI_HANDLE(dev))
return acpi_dma_request_slave_chan_by_name(dev, name);
if (has_acpi_companion(dev) && !chan)
chan = acpi_dma_request_slave_chan_by_name(dev, name);
return ERR_PTR(-ENODEV);
if (chan) {
/* Valid channel found or requester need to be deferred */
if (!IS_ERR(chan) || PTR_ERR(chan) == -EPROBE_DEFER)
return chan;
}
/* Try to find the channel via the DMA filter map(s) */
mutex_lock(&dma_list_mutex);
list_for_each_entry_safe(d, _d, &dma_device_list, global_node) {
dma_cap_mask_t mask;
const struct dma_slave_map *map = dma_filter_match(d, name, dev);
if (!map)
continue;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
chan = find_candidate(d, &mask, d->filter.fn, map->param);
if (!IS_ERR(chan))
break;
}
mutex_unlock(&dma_list_mutex);
return chan ? chan : ERR_PTR(-EPROBE_DEFER);
}
EXPORT_SYMBOL_GPL(dma_request_slave_channel_reason);
EXPORT_SYMBOL_GPL(dma_request_chan);
/**
* dma_request_slave_channel - try to allocate an exclusive slave channel
......@@ -695,17 +745,35 @@ EXPORT_SYMBOL_GPL(dma_request_slave_channel_reason);
struct dma_chan *dma_request_slave_channel(struct device *dev,
const char *name)
{
struct dma_chan *ch = dma_request_slave_channel_reason(dev, name);
struct dma_chan *ch = dma_request_chan(dev, name);
if (IS_ERR(ch))
return NULL;
dma_cap_set(DMA_PRIVATE, ch->device->cap_mask);
ch->device->privatecnt++;
return ch;
}
EXPORT_SYMBOL_GPL(dma_request_slave_channel);
/**
* dma_request_chan_by_mask - allocate a channel satisfying certain capabilities
* @mask: capabilities that the channel must satisfy
*
* Returns pointer to appropriate DMA channel on success or an error pointer.
*/
struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask)
{
struct dma_chan *chan;
if (!mask)
return ERR_PTR(-ENODEV);
chan = __dma_request_channel(mask, NULL, NULL);
if (!chan)
chan = ERR_PTR(-ENODEV);
return chan;
}
EXPORT_SYMBOL_GPL(dma_request_chan_by_mask);
void dma_release_channel(struct dma_chan *chan)
{
mutex_lock(&dma_list_mutex);
......
......@@ -2297,6 +2297,10 @@ static int edma_probe(struct platform_device *pdev)
edma_set_chmap(&ecc->slave_chans[i], ecc->dummy_slot);
}
ecc->dma_slave.filter.map = info->slave_map;
ecc->dma_slave.filter.mapcnt = info->slavecnt;
ecc->dma_slave.filter.fn = edma_filter_fn;
ret = dma_async_device_register(&ecc->dma_slave);
if (ret) {
dev_err(dev, "slave ddev registration failed (%d)\n", ret);
......
......@@ -1203,6 +1203,10 @@ static int omap_dma_probe(struct platform_device *pdev)
return rc;
}
od->ddev.filter.map = od->plat->slave_map;
od->ddev.filter.mapcnt = od->plat->slavecnt;
od->ddev.filter.fn = omap_dma_filter_fn;
rc = dma_async_device_register(&od->ddev);
if (rc) {
pr_warn("OMAP-DMA: failed to register slave DMA engine device: %d\n",
......
......@@ -606,12 +606,39 @@ enum dmaengine_alignment {
DMAENGINE_ALIGN_64_BYTES = 6,
};
/**
* struct dma_slave_map - associates slave device and it's slave channel with
* parameter to be used by a filter function
* @devname: name of the device
* @slave: slave channel name
* @param: opaque parameter to pass to struct dma_filter.fn
*/
struct dma_slave_map {
const char *devname;
const char *slave;
void *param;
};
/**
* struct dma_filter - information for slave device/channel to filter_fn/param
* mapping
* @fn: filter function callback
* @mapcnt: number of slave device/channel in the map
* @map: array of channel to filter mapping data
*/
struct dma_filter {
dma_filter_fn fn;
int mapcnt;
const struct dma_slave_map *map;
};
/**
* struct dma_device - info on the entity supplying DMA services
* @chancnt: how many DMA channels are supported
* @privatecnt: how many DMA channels are requested by dma_request_channel
* @channels: the list of struct dma_chan
* @global_node: list_head for global dma_device_list
* @filter: information for device/slave to filter function/param mapping
* @cap_mask: one or more dma_capability flags
* @max_xor: maximum number of xor sources, 0 if no capability
* @max_pq: maximum number of PQ sources and PQ-continue capability
......@@ -667,6 +694,7 @@ struct dma_device {
unsigned int privatecnt;
struct list_head channels;
struct list_head global_node;
struct dma_filter filter;
dma_cap_mask_t cap_mask;
unsigned short max_xor;
unsigned short max_pq;
......@@ -1142,9 +1170,11 @@ enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
void dma_issue_pending_all(void);
struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
dma_filter_fn fn, void *fn_param);
struct dma_chan *dma_request_slave_channel_reason(struct device *dev,
const char *name);
struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name);
struct dma_chan *dma_request_chan(struct device *dev, const char *name);
struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask);
void dma_release_channel(struct dma_chan *chan);
int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps);
#else
......@@ -1168,16 +1198,21 @@ static inline struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
{
return NULL;
}
static inline struct dma_chan *dma_request_slave_channel_reason(
struct device *dev, const char *name)
{
return ERR_PTR(-ENODEV);
}
static inline struct dma_chan *dma_request_slave_channel(struct device *dev,
const char *name)
{
return NULL;
}
static inline struct dma_chan *dma_request_chan(struct device *dev,
const char *name)
{
return ERR_PTR(-ENODEV);
}
static inline struct dma_chan *dma_request_chan_by_mask(
const dma_cap_mask_t *mask)
{
return ERR_PTR(-ENODEV);
}
static inline void dma_release_channel(struct dma_chan *chan)
{
}
......@@ -1188,6 +1223,8 @@ static inline int dma_get_slave_caps(struct dma_chan *chan,
}
#endif
#define dma_request_slave_channel_reason(dev, name) dma_request_chan(dev, name)
static inline int dmaengine_desc_set_reuse(struct dma_async_tx_descriptor *tx)
{
struct dma_slave_caps caps;
......
......@@ -267,6 +267,9 @@ struct omap_dma_reg {
u8 type;
};
#define SDMA_FILTER_PARAM(hw_req) ((int[]) { (hw_req) })
struct dma_slave_map;
/* System DMA platform data structure */
struct omap_system_dma_plat_info {
const struct omap_dma_reg *reg_map;
......@@ -278,6 +281,9 @@ struct omap_system_dma_plat_info {
void (*clear_dma)(int lch);
void (*dma_write)(u32 val, int reg, int lch);
u32 (*dma_read)(int reg, int lch);
const struct dma_slave_map *slave_map;
int slavecnt;
};
#ifdef CONFIG_ARCH_OMAP2PLUS
......
......@@ -53,12 +53,16 @@ enum dma_event_q {
#define EDMA_CTLR(i) ((i) >> 16)
#define EDMA_CHAN_SLOT(i) ((i) & 0xffff)
#define EDMA_FILTER_PARAM(ctlr, chan) ((int[]) { EDMA_CTLR_CHAN(ctlr, chan) })
struct edma_rsv_info {
const s16 (*rsv_chans)[2];
const s16 (*rsv_slots)[2];
};
struct dma_slave_map;
/* platform_data for EDMA driver */
struct edma_soc_info {
/*
......@@ -76,6 +80,9 @@ struct edma_soc_info {
s8 (*queue_priority_mapping)[2];
const s16 (*xbar_chans)[2];
const struct dma_slave_map *slave_map;
int slavecnt;
};
#endif
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