summaryrefslogtreecommitdiffstats
path: root/drivers/i2c
diff options
context:
space:
mode:
authorGuenter Roeck <linux@roeck-us.net>2018-02-26 21:46:52 +0100
committerWolfram Sang <wsa@the-dreams.de>2018-03-02 11:16:52 +0100
commit0e89b2fec748177899c1f9ebfbe87714ffa248eb (patch)
tree5c9f4e59780ff08005f918b53ec1bfdf222eaaa0 /drivers/i2c
parenti2c: reformat comments around i2c_smbus_xfer_emulated() (diff)
downloadlinux-0e89b2fec748177899c1f9ebfbe87714ffa248eb.tar.xz
linux-0e89b2fec748177899c1f9ebfbe87714ffa248eb.zip
i2c: piix4: Use usleep_range()
The piix4 i2c driver is extremely slow. Replacing msleep() with usleep_range() increases its speed substantially. Use sleep ranges similar to those used in the i2c-801 driver to keep things simple. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-piix4.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 462948e2c535..4c1f6aaec0fc 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -462,13 +462,13 @@ static int piix4_transaction(struct i2c_adapter *piix4_adapter)
/* We will always wait for a fraction of a second! (See PIIX4 docs errata) */
if (srvrworks_csb5_delay) /* Extra delay for SERVERWORKS_CSB5 */
- msleep(2);
+ usleep_range(2000, 2100);
else
- msleep(1);
+ usleep_range(250, 500);
while ((++timeout < MAX_TIMEOUT) &&
((temp = inb_p(SMBHSTSTS)) & 0x01))
- msleep(1);
+ usleep_range(250, 500);
/* If the SMBus is still busy, we give up */
if (timeout == MAX_TIMEOUT) {