sh: dma-api channel capability extensions.

This extends the SH DMA API for allowing handling of DMA
channels based off of their respective capabilities.

A couple of functions are added to the existing API,
the core bits are register_chan_caps() for registering
channel capabilities, and request_dma_bycap() for fetching
a channel dynamically based off of a capability set.

Signed-off-by: Mark Glaisher <mark.glaisher@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 29 insertions, 11 deletions

diff --git a/include/asm-sh/dma.h b/include/asm-sh/dma.h
index d9daa028689..faf3051cd42 100644
--- a/include/asm-sh/dma.h
+++ b/include/asm-sh/dma.h
@@ -14,9 +14,7 @@
 #include <linux/spinlock.h>
 #include <linux/wait.h>
 #include <linux/sysdev.h>
-#include <linux/device.h>
 #include <asm/cpu/dma.h>
-#include <asm/semaphore.h>
 
 /* The maximum address that we can perform a DMA transfer to on this platform */
 /* Don't define MAX_DMA_ADDRESS; it's useless on the SuperH and any
@@ -46,16 +44,21 @@
  * DMAC (dma_info) flags
  */
 enum {
-        DMAC_CHANNELS_CONFIGURED        = 0x00,
-        DMAC_CHANNELS_TEI_CAPABLE       = 0x01,
+        DMAC_CHANNELS_CONFIGURED        = 0x01,
+        DMAC_CHANNELS_TEI_CAPABLE       = 0x02, /* Transfer end interrupt */
 };
 
 /*
  * DMA channel capabilities / flags
  */
 enum {
-        DMA_TEI_CAPABLE                 = 0x01,
-        DMA_CONFIGURED                  = 0x02,
+        DMA_CONFIGURED                  = 0x01,
+
+        /*
+         * Transfer end interrupt, inherited from DMAC.
+         * wait_queue used in dma_wait_for_completion.
+         */
+        DMA_TEI_CAPABLE                 = 0x02,
 };
 
 extern spinlock_t dma_spin_lock;
@@ -68,28 +71,31 @@ struct dma_ops {
 
         int (*get_residue)(struct dma_channel *chan);
         int (*xfer)(struct dma_channel *chan);
-        void (*configure)(struct dma_channel *chan, unsigned long flags);
+        int (*configure)(struct dma_channel *chan, unsigned long flags);
+        int (*extend)(struct dma_channel *chan, unsigned long op, void *param);
 };
 
 struct dma_channel {
-        char dev_id[16];
+        char dev_id[16];                /* unique name per DMAC of channel */
 
-        unsigned int chan;              /* Physical channel number */
+        unsigned int chan;              /* DMAC channel number */
         unsigned int vchan;             /* Virtual channel number */
+
         unsigned int mode;
         unsigned int count;
 
         unsigned long sar;
         unsigned long dar;
 
+        const char **caps;
+
         unsigned long flags;
         atomic_t busy;
 
-        struct semaphore sem;
         wait_queue_head_t wait_queue;
 
         struct sys_device dev;
-        char *name;
+        void *priv_data;
 };
 
 struct dma_info {
@@ -103,6 +109,12 @@ struct dma_info {
         struct dma_channel *channels;
 
         struct list_head list;
+        int first_channel_nr;
+};
+
+struct dma_chan_caps {
+        int ch_num;
+        const char **caplist;
 };
 
 #define to_dma_channel(channel) container_of(channel, struct dma_channel, dev)
@@ -121,6 +133,8 @@ extern int dma_xfer(unsigned int chan, unsigned long from,
 #define dma_read_page(chan, from, to)   \
         dma_read(chan, from, to, PAGE_SIZE)
 
+extern int request_dma_bycap(const char **dmac, const char **caps,
+                             const char *dev_id);
 extern int request_dma(unsigned int chan, const char *dev_id);
 extern void free_dma(unsigned int chan);
 extern int get_dma_residue(unsigned int chan);
@@ -131,6 +145,10 @@ extern void dma_configure_channel(unsigned int chan, unsigned long flags);
 
 extern int register_dmac(struct dma_info *info);
 extern void unregister_dmac(struct dma_info *info);
+extern struct dma_info *get_dma_info_by_name(const char *dmac_name);
+
+extern int dma_extend(unsigned int chan, unsigned long op, void *param);
+extern int register_chan_caps(const char *dmac, struct dma_chan_caps *capslist);
 
 #ifdef CONFIG_SYSFS
 /* arch/sh/drivers/dma/dma-sysfs.c */