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@xxxxxxxxx>
---
drivers/i2c/busses/i2c-isch.c | 10 +++++-----
1 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/i2c/busses/i2c-isch.c b/drivers/i2c/busses/i2c-isch.c
index 6561d27..f90a605 100644
--- 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;
}
--
1.7.5.4
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