i2c-isch: Decrease delay in command completion check loop

Generally it is not needed to wait for 1 msec, the SMBus get often ready
in less than 200 usecs.

msleep(1) can wait up to 20 msecs... It has a significant impact when
there is a burst of transactions on the bus.

Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

diff --git a/drivers/i2c/busses/i2c-isch.c b/drivers/i2c/busses/i2c-isch.c
index 6561d275b8cf20fd9ed056c1963d66fd4c318899..f90a6057508dd7ffe0dabd6f30694ab9b06a36f4 100644 (file)
--- a/drivers/i2c/busses/i2c-isch.c
+++ b/drivers/i2c/busses/i2c-isch.c
@@ -47,7 +47,7 @@
 #define SMBBLKDAT      (0x20 + sch_smba)
 
 /* Other settings */
-#define MAX_TIMEOUT    500
+#define MAX_RETRIES    5000
 
 /* I2C constants */
 #define SCH_QUICK              0x00
@@ -68,7 +68,7 @@ static int sch_transaction(void)
 {
        int temp;
        int result = 0;
-       int timeout = 0;
+       int retries = 0;
 
        dev_dbg(&sch_adapter.dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
                "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb(SMBHSTCNT),
@@ -100,12 +100,12 @@ static int sch_transaction(void)
        outb(inb(SMBHSTCNT) | 0x10, SMBHSTCNT);
 
        do {
-               msleep(1);
+               usleep_range(100, 200);
                temp = inb(SMBHSTSTS) & 0x0f;
-       } while ((temp & 0x08) && (timeout++ < MAX_TIMEOUT));
+       } while ((temp & 0x08) && (retries++ < MAX_RETRIES));
 
        /* If the SMBus is still busy, we give up */
-       if (timeout > MAX_TIMEOUT) {
+       if (retries > MAX_RETRIES) {
                dev_err(&sch_adapter.dev, "SMBus Timeout!\n");
                result = -ETIMEDOUT;
        }