From d592afe9018e193f675b8c710fb1e66e44851ec8 Mon Sep 17 00:00:00 2001
From: Clark Wang <xiaoning.wang@nxp.com>
Date: Tue, 5 Mar 2019 14:56:55 +0800
Subject: [PATCH] MLK-21023 i2c: rpmsg-imx: add mutex lock when transfer i2c
messages
I2c_lock_bus function in i2c-core-base will not stop the transfer to
different devices on different buses at the same time.
Since the multiple rpmsg i2c buses share one rpmsg channel, so it has to
add mutex to protect rpmsg resource accessing.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
---
drivers/i2c/busses/i2c-rpmsg-imx.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-rpmsg-imx.c b/drivers/i2c/busses/i2c-rpmsg-imx.c
index 37f39609da2ea5..a978b61e741786 100644
--- a/drivers/i2c/busses/i2c-rpmsg-imx.c
+++ b/drivers/i2c/busses/i2c-rpmsg-imx.c
@@ -108,6 +108,7 @@ struct i2c_rpmsg_info {
struct device *dev;
struct i2c_rpmsg_msg *msg;
struct completion cmd_complete;
+ struct mutex lock;
};
static struct i2c_rpmsg_info i2c_rpmsg;
@@ -271,6 +272,7 @@ static int i2c_rpmsg_probe(struct rpmsg_device *rpdev)
i2c_rpmsg.rpdev = rpdev;
+ mutex_init(&i2c_rpmsg.lock);
init_completion(&i2c_rpmsg.cmd_complete);
dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",
@@ -309,6 +311,8 @@ static int i2c_rpbus_xfer(struct i2c_adapter *adapter,
int i, ret;
bool is_last = false;
+ mutex_lock(&i2c_rpmsg.lock);
+
for (i = 0; i < num; i++) {
if (i == num - 1)
is_last = true;
@@ -318,18 +322,23 @@ static int i2c_rpbus_xfer(struct i2c_adapter *adapter,
if (pmsg->flags & I2C_M_RD) {
ret = i2c_rpmsg_read(pmsg, &i2c_rpmsg,
rdata->adapter.nr, is_last);
- if (ret < 0)
+ if (ret < 0) {
+ mutex_unlock(&i2c_rpmsg.lock);
return ret;
+ }
pmsg->len = ret;
} else {
ret = i2c_rpmsg_write(pmsg, &i2c_rpmsg,
rdata->adapter.nr, is_last);
- if (ret < 0)
+ if (ret < 0) {
+ mutex_unlock(&i2c_rpmsg.lock);
return ret;
+ }
}
}
+ mutex_unlock(&i2c_rpmsg.lock);
return num;
}
--
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