i2c: i801: Replace waitqueue with completion API

Using the completion API is more intuitive and it allows to simplify
the code. Note that we don't have to set priv->status = 0 any longer
with the completion API.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index bfea94d..738204d 100644 (file)
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -103,7 +103,7 @@
 #include <linux/dmi.h>
 #include <linux/slab.h>
 #include <linux/string.h>
-#include <linux/wait.h>
+#include <linux/completion.h>
 #include <linux/err.h>
 #include <linux/platform_device.h>
 #include <linux/platform_data/itco_wdt.h>
@@ -270,7 +270,7 @@ struct i801_priv {
        unsigned int features;
 
        /* isr processing */
-       wait_queue_head_t waitq;
+       struct completion done;
        u8 status;
 
        /* Command state used by isr for byte-by-byte block transactions */
@@ -496,24 +496,19 @@ static int i801_wait_byte_done(struct i801_priv *priv)
 static int i801_transaction(struct i801_priv *priv, int xact)
 {
        int status;
-       int result;
+       unsigned long result;
        const struct i2c_adapter *adap = &priv->adapter;
 
-       result = i801_check_pre(priv);
-       if (result < 0)
-               return result;
+       status = i801_check_pre(priv);
+       if (status < 0)
+               return status;
 
        if (priv->features & FEATURE_IRQ) {
+               reinit_completion(&priv->done);
                outb_p(xact | SMBHSTCNT_INTREN | SMBHSTCNT_START,
                       SMBHSTCNT(priv));
-               result = wait_event_timeout(priv->waitq,
-                                           (status = priv->status),
-                                           adap->timeout);
-               if (!result)
-                       status = -ETIMEDOUT;
-
-               priv->status = 0;
-               return i801_check_post(priv, status);
+               result = wait_for_completion_timeout(&priv->done, adap->timeout);
+               return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);
        }
 
        /* the current contents of SMBHSTCNT can be overwritten, since PEC,
@@ -638,7 +633,7 @@ static irqreturn_t i801_host_notify_isr(struct i801_priv *priv)
  *      DEV_ERR - Invalid command, NAK or communication timeout
  *      BUS_ERR - SMI# transaction collision
  *      FAILED - transaction was canceled due to a KILL request
- *    When any of these occur, update ->status and wake up the waitq.
+ *    When any of these occur, update ->status and signal completion.
  *    ->status must be cleared before kicking off the next transaction.
  *
  * 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt
@@ -675,7 +670,7 @@ static irqreturn_t i801_isr(int irq, void *dev_id)
        if (status) {
                outb_p(status, SMBHSTSTS(priv));
                priv->status = status;
-               wake_up(&priv->waitq);
+               complete(&priv->done);
        }
 
        return IRQ_HANDLED;
@@ -694,15 +689,15 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
        int i, len;
        int smbcmd;
        int status;
-       int result;
+       unsigned long result;
        const struct i2c_adapter *adap = &priv->adapter;
 
        if (command == I2C_SMBUS_BLOCK_PROC_CALL)
                return -EOPNOTSUPP;
 
-       result = i801_check_pre(priv);
-       if (result < 0)
-               return result;
+       status = i801_check_pre(priv);
+       if (status < 0)
+               return status;
 
        len = data->block[0];
 
@@ -726,15 +721,10 @@ static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
                priv->count = 0;
                priv->data = &data->block[1];
 
+               reinit_completion(&priv->done);
                outb_p(priv->cmd | SMBHSTCNT_START, SMBHSTCNT(priv));
-               result = wait_event_timeout(priv->waitq,
-                                           (status = priv->status),
-                                           adap->timeout);
-               if (!result)
-                       status = -ETIMEDOUT;
-
-               priv->status = 0;
-               return i801_check_post(priv, status);
+               result = wait_for_completion_timeout(&priv->done, adap->timeout);
+               return i801_check_post(priv, result ? priv->status : -ETIMEDOUT);
        }
 
        for (i = 1; i <= len; i++) {
@@ -1889,7 +1879,7 @@ static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
        }
 
        if (priv->features & FEATURE_IRQ) {
-               init_waitqueue_head(&priv->waitq);
+               init_completion(&priv->done);
 
                err = devm_request_irq(&dev->dev, dev->irq, i801_isr,
                                       IRQF_SHARED,