This allows clients running in atomic context to poll for messages to
arrive.
Signed-off-by: Hector Martin <marcan@xxxxxxxxx>
---
drivers/mailbox/apple-mailbox.c | 37 ++++++++++++++++++++++++++++++---
1 file changed, 34 insertions(+), 3 deletions(-)
diff --git a/drivers/mailbox/apple-mailbox.c b/drivers/mailbox/apple-mailbox.c
index 33e7acf71e3e..e0c2bf7c6338 100644
--- a/drivers/mailbox/apple-mailbox.c
+++ b/drivers/mailbox/apple-mailbox.c
@@ -26,6 +26,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
+#include <linux/spinlock.h>
#include <linux/types.h>
#define APPLE_ASC_MBOX_CONTROL_FULL BIT(16)
@@ -101,6 +102,7 @@ struct apple_mbox {
struct device *dev;
struct mbox_controller controller;
+ spinlock_t rx_lock;
};
static const struct of_device_id apple_mbox_of_match[];
@@ -204,13 +206,16 @@ static irqreturn_t apple_mbox_send_empty_irq(int irq, void *data)
return IRQ_HANDLED;
}
-static irqreturn_t apple_mbox_recv_irq(int irq, void *data)
+static int apple_mbox_poll_data(struct apple_mbox *apple_mbox)
{
- struct apple_mbox *apple_mbox = data;
+
struct apple_mbox_msg msg;
+ int ret = 0;
- while (apple_mbox_hw_recv(apple_mbox, &msg) == 0)
+ while (apple_mbox_hw_recv(apple_mbox, &msg) == 0) {
mbox_chan_received_data(&apple_mbox->chan, (void *)&msg);
+ ret++;
+ }
/*
* The interrupt will keep firing even if there are no more messages
@@ -225,9 +230,33 @@ static irqreturn_t apple_mbox_recv_irq(int irq, void *data)
apple_mbox->regs + apple_mbox->hw->irq_ack);
}
+ return ret;
+}
+
+static irqreturn_t apple_mbox_recv_irq(int irq, void *data)
+{
+ struct apple_mbox *apple_mbox = data;
+
+ spin_lock(&apple_mbox->rx_lock);
+ apple_mbox_poll_data(apple_mbox);
+ spin_unlock(&apple_mbox->rx_lock);
+
return IRQ_HANDLED;
}
+static bool apple_mbox_chan_poll_data(struct mbox_chan *chan)
+{
+ struct apple_mbox *apple_mbox = chan->con_priv;
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&apple_mbox->rx_lock, flags);
+ ret = apple_mbox_poll_data(apple_mbox);
+ spin_unlock_irqrestore(&apple_mbox->rx_lock, flags);
+
+ return ret > 0;
+}
+
static int apple_mbox_chan_flush(struct mbox_chan *chan, unsigned long timeout)
{
struct apple_mbox *apple_mbox = chan->con_priv;
@@ -276,6 +305,7 @@ static void apple_mbox_chan_shutdown(struct mbox_chan *chan)
static const struct mbox_chan_ops apple_mbox_ops = {
.send_data = apple_mbox_chan_send_data,
+ .poll_data = apple_mbox_chan_poll_data,
.flush = apple_mbox_chan_flush,
.startup = apple_mbox_chan_startup,
.shutdown = apple_mbox_chan_shutdown,
@@ -331,6 +361,7 @@ static int apple_mbox_probe(struct platform_device *pdev)
mbox->controller.txdone_irq = true;
mbox->controller.of_xlate = apple_mbox_of_xlate;
mbox->chan.con_priv = mbox;
+ spin_lock_init(&mbox->rx_lock);
irqname = devm_kasprintf(dev, GFP_KERNEL, "%s-recv", dev_name(dev));
if (!irqname)
--
2.35.1
