Introduce two new functions nvec_msg_alloc() and nvec_msg_free()
that allocate and free message buffers from the internal pool
of messages.
Signed-off-by: Julian Andres Klode <jak@xxxxxxxxxxxxx>
---
drivers/staging/nvec/nvec.c | 21 +++++++++++++++++++++
drivers/staging/nvec/nvec.h | 6 ++++++
2 files changed, 27 insertions(+), 0 deletions(-)
diff --git a/drivers/staging/nvec/nvec.c b/drivers/staging/nvec/nvec.c
index 43a83a9..8a97241 100644
--- a/drivers/staging/nvec/nvec.c
+++ b/drivers/staging/nvec/nvec.c
@@ -17,6 +17,7 @@
#include <asm/irq.h>
+#include <linux/atomic.h>
#include <linux/completion.h>
#include <linux/interrupt.h>
#include <linux/io.h>
@@ -91,6 +92,26 @@ static int nvec_status_notifier(struct notifier_block *nb,
return NOTIFY_OK;
}
+static struct nvec_msg *nvec_msg_alloc(struct nvec_chip *nvec)
+{
+ size_t i;
+ for (i = 0; i < NVEC_POOL_SIZE; i++)
+ if (atomic_xchg(&nvec->msg_pool[i].used, 1) == 0) {
+ dev_vdbg(nvec->dev, "INFO: Alloc %u\n", (uint) i);
+ return &nvec->msg_pool[i];
+ }
+
+ dev_err(nvec->dev, "could not allocate buffer\n");
+
+ return NULL;
+}
+
+static void nvec_msg_free(struct nvec_chip *nvec, struct nvec_msg *msg)
+{
+ dev_vdbg(nvec->dev, "INFO: Free %i\n", (int) (msg - nvec->msg_pool));
+ atomic_set(&msg->used, 0);
+}
+
void nvec_write_async(struct nvec_chip *nvec, const unsigned char *data,
short size)
{
diff --git a/drivers/staging/nvec/nvec.h b/drivers/staging/nvec/nvec.h
index fe11225..5440802 100644
--- a/drivers/staging/nvec/nvec.h
+++ b/drivers/staging/nvec/nvec.h
@@ -16,9 +16,13 @@
#ifndef __LINUX_MFD_NVEC
#define __LINUX_MFD_NVEC
+#include <linux/atomic.h>
#include <linux/notifier.h>
#include <linux/semaphore.h>
+/* NVEC_POOL_SIZE - Size of the pool in &struct nvec_msg */
+#define NVEC_POOL_SIZE 64
+
typedef enum {
NVEC_2BYTES,
NVEC_3BYTES,
@@ -52,6 +56,7 @@ struct nvec_msg {
unsigned short size;
unsigned short pos;
struct list_head node;
+ atomic_t used;
};
struct nvec_subdev {
@@ -78,6 +83,7 @@ struct nvec_chip {
struct notifier_block nvec_status_notifier;
struct work_struct rx_work, tx_work;
struct nvec_msg *rx, *tx;
+ struct nvec_msg msg_pool[NVEC_POOL_SIZE];
/* sync write stuff */
struct semaphore sync_write_mutex;
--
1.7.5.4
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