| Message ID | 20171109222053.27093-1-wsa+renesas@sang-engineering.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [RFT] i2c: sh_mobile: avoid unnecessary register read | expand |
Hi Wolfram, On Thu, Nov 09, 2017 at 11:20:53PM +0100, Wolfram Sang wrote: > There is no data when the first WAIT interrupt arrives. No need to read > something then. > > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> > --- > > I am not super happy with (real pos >= 0) done twice, but I didn't find a > better solution yet. The compiler will make this cheap anyhow, I guess. > > Jacopo: can you please test this on top of all other patches? No regressions on Migo-R during image capture. Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org> Thanks j > > drivers/i2c/busses/i2c-sh_mobile.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c > index 80561ffbcf7b46..40a66d466c3c49 100644 > --- a/drivers/i2c/busses/i2c-sh_mobile.c > +++ b/drivers/i2c/busses/i2c-sh_mobile.c > @@ -433,8 +433,9 @@ static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd) > break; > } > data = i2c_op(pd, OP_RX_STOP_DATA, 0); > - } else > + } else if (real_pos >= 0) { > data = i2c_op(pd, OP_RX, 0); > + } > > if (real_pos >= 0) > pd->msg->buf[real_pos] = data; > -- > 2.11.0 >
On Thu, Nov 09, 2017 at 11:20:53PM +0100, Wolfram Sang wrote: > There is no data when the first WAIT interrupt arrives. No need to read > something then. > > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Applied to for-next, thanks!
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c index 80561ffbcf7b46..40a66d466c3c49 100644 --- a/drivers/i2c/busses/i2c-sh_mobile.c +++ b/drivers/i2c/busses/i2c-sh_mobile.c @@ -433,8 +433,9 @@ static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd) break; } data = i2c_op(pd, OP_RX_STOP_DATA, 0); - } else + } else if (real_pos >= 0) { data = i2c_op(pd, OP_RX, 0); + } if (real_pos >= 0) pd->msg->buf[real_pos] = data;
There is no data when the first WAIT interrupt arrives. No need to read something then. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> --- I am not super happy with (real pos >= 0) done twice, but I didn't find a better solution yet. The compiler will make this cheap anyhow, I guess. Jacopo: can you please test this on top of all other patches? drivers/i2c/busses/i2c-sh_mobile.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)