i2c: i801: Improve status polling

Polling uses the same timeout as irq mode: 400 * 500us = 200ms = HZ / 5.
So let's use the adapter->timeout value also for polling. This has the
advantage that userspace can control the timeout value for polling as
well. In addition change the code to make it better readable.
Last but not least remove the timeout debug messages. Calls to both
functions are followed by a call to i801_check_post() that will print
an error message in case of timeout.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Tested-by: Jean Delvare <jdelvare@suse.de>
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 f6d7866f11c38cd48485a5aabcbd34566d0c76b1..2c6e84108013f000fd5bc789600cfc8b3a14bd0f 100644 (file)
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -156,9 +156,6 @@
 #define SMBAUXCTL_CRC          BIT(0)
 #define SMBAUXCTL_E32B         BIT(1)
 
-/* Other settings */
-#define MAX_RETRIES            400
-
 /* I801 command constants */
 #define I801_QUICK             0x00
 #define I801_BYTE              0x04
@@ -447,42 +444,35 @@ static int i801_check_post(struct i801_priv *priv, int status)
 /* Wait for BUSY being cleared and either INTR or an error flag being set */
 static int i801_wait_intr(struct i801_priv *priv)
 {
-       int timeout = 0;
-       int status;
+       unsigned long timeout = jiffies + priv->adapter.timeout;
+       int status, busy;
 
-       /* We will always wait for a fraction of a second! */
        do {
                usleep_range(250, 500);
                status = inb_p(SMBHSTSTS(priv));
-       } while (((status & SMBHSTSTS_HOST_BUSY) ||
-                 !(status & (STATUS_ERROR_FLAGS | SMBHSTSTS_INTR))) &&
-                (timeout++ < MAX_RETRIES));
+               busy = status & SMBHSTSTS_HOST_BUSY;
+               status &= STATUS_ERROR_FLAGS | SMBHSTSTS_INTR;
+               if (!busy && status)
+                       return status;
+       } while (time_is_after_eq_jiffies(timeout));
 
-       if (timeout > MAX_RETRIES) {
-               dev_dbg(&priv->pci_dev->dev, "INTR Timeout!\n");
-               return -ETIMEDOUT;
-       }
-       return status & (STATUS_ERROR_FLAGS | SMBHSTSTS_INTR);
+       return -ETIMEDOUT;
 }
 
 /* Wait for either BYTE_DONE or an error flag being set */
 static int i801_wait_byte_done(struct i801_priv *priv)
 {
-       int timeout = 0;
+       unsigned long timeout = jiffies + priv->adapter.timeout;
        int status;
 
-       /* We will always wait for a fraction of a second! */
        do {
                usleep_range(250, 500);
                status = inb_p(SMBHSTSTS(priv));
-       } while (!(status & (STATUS_ERROR_FLAGS | SMBHSTSTS_BYTE_DONE)) &&
-                (timeout++ < MAX_RETRIES));
+               if (status & (STATUS_ERROR_FLAGS | SMBHSTSTS_BYTE_DONE))
+                       return status & STATUS_ERROR_FLAGS;
+       } while (time_is_after_eq_jiffies(timeout));
 
-       if (timeout > MAX_RETRIES) {
-               dev_dbg(&priv->pci_dev->dev, "BYTE_DONE Timeout!\n");
-               return -ETIMEDOUT;
-       }
-       return status & STATUS_ERROR_FLAGS;
+       return -ETIMEDOUT;
 }
 
 static int i801_transaction(struct i801_priv *priv, int xact)