Message ID | 1519678013-32749-1-git-send-email-linux@roeck-us.net |
---|---|
State | Accepted |
Headers | show |
Series | [v2,1/2] i2c: piix4: Use usleep_range() | expand |
On Mon, 26 Feb 2018 12:46:52 -0800, Guenter Roeck wrote: > 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> > --- > v2: Changed timeout values for usleep_range() > 2000/2000 -> 2000/2100 > 500/1000 -> 250/500 > 200/500 -> 250/500 > > drivers/i2c/busses/i2c-piix4.c | 6 +++--- > 1 file 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) { Reviewed-by: Jean Delvare <jdelvare@suse.de>
On Mon, Feb 26, 2018 at 12:46:52PM -0800, Guenter Roeck wrote: > 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> Applied to for-next, thanks!
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) {
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> --- v2: Changed timeout values for usleep_range() 2000/2000 -> 2000/2100 500/1000 -> 250/500 200/500 -> 250/500 drivers/i2c/busses/i2c-piix4.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)