i2c: rcar: remove spinlock
authorWolfram Sang <wsa+renesas@sang-engineering.com>
Thu, 3 Sep 2015 20:20:07 +0000 (22:20 +0200)
committerWolfram Sang <wsa@the-dreams.de>
Fri, 9 Oct 2015 21:30:12 +0000 (22:30 +0100)
We make sure to reinit the HW in the timeout case; then we know that
interrupts are always disabled in the sections protected by the
spinlock. Thus, we can simply remove it which is a preparation for
further refactoring. While here, rename the timeout variable to
time_left which is way more readable.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
drivers/i2c/busses/i2c-rcar.c

index 3594cdab2573b60b80de9d617cf607bfcdb661b6..e65418b34d868e89181323393b44d4cc14e44601 100644 (file)
@@ -34,7 +34,6 @@
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
-#include <linux/spinlock.h>
 
 /* register offsets */
 #define ICSCR  0x00    /* slave ctrl */
@@ -110,7 +109,6 @@ struct rcar_i2c_priv {
        struct i2c_msg  *msg;
        struct clk *clk;
 
-       spinlock_t lock;
        wait_queue_head_t wait;
 
        int pos;
@@ -428,9 +426,6 @@ static irqreturn_t rcar_i2c_irq(int irq, void *ptr)
        irqreturn_t result = IRQ_HANDLED;
        u32 msr;
 
-       /*-------------- spin lock -----------------*/
-       spin_lock(&priv->lock);
-
        if (rcar_i2c_slave_irq(priv))
                goto exit;
 
@@ -477,9 +472,6 @@ out:
        }
 
 exit:
-       spin_unlock(&priv->lock);
-       /*-------------- spin unlock -----------------*/
-
        return result;
 }
 
@@ -489,9 +481,8 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 {
        struct rcar_i2c_priv *priv = i2c_get_adapdata(adap);
        struct device *dev = rcar_i2c_priv_to_dev(priv);
-       unsigned long flags;
        int i, ret;
-       long timeout;
+       long time_left;
 
        pm_runtime_get_sync(dev);
 
@@ -506,9 +497,6 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
                        break;
                }
 
-               /*-------------- spin lock -----------------*/
-               spin_lock_irqsave(&priv->lock, flags);
-
                /* init each data */
                priv->msg       = &msgs[i];
                priv->pos       = 0;
@@ -518,13 +506,11 @@ static int rcar_i2c_master_xfer(struct i2c_adapter *adap,
 
                rcar_i2c_prepare_msg(priv);
 
-               spin_unlock_irqrestore(&priv->lock, flags);
-               /*-------------- spin unlock -----------------*/
-
-               timeout = wait_event_timeout(priv->wait,
+               time_left = wait_event_timeout(priv->wait,
                                             rcar_i2c_flags_has(priv, ID_DONE),
                                             adap->timeout);
-               if (!timeout) {
+               if (!time_left) {
+                       rcar_i2c_init(priv);
                        ret = -ETIMEDOUT;
                        break;
                }
@@ -658,7 +644,6 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 
        irq = platform_get_irq(pdev, 0);
        init_waitqueue_head(&priv->wait);
-       spin_lock_init(&priv->lock);
 
        adap = &priv->adap;
        adap->nr = pdev->id;