| Message ID | 1445395021-4204-5-git-send-email-jaedon.shin@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
On Wed, Oct 21, 2015 at 11:36:56AM +0900, Jaedon Shin wrote: > Removes the condition of a message with under 32 bytes in length. The > messages that do not require an ACK are I2C_M_IGNORE_NAK flag. Makes me wonder why it worked before? Kamal? > > Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com> > --- > drivers/i2c/busses/i2c-brcmstb.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-brcmstb.c b/drivers/i2c/busses/i2c-brcmstb.c > index 2d7d155029dc..53eb8b0c9bad 100644 > --- a/drivers/i2c/busses/i2c-brcmstb.c > +++ b/drivers/i2c/busses/i2c-brcmstb.c > @@ -330,7 +330,7 @@ static int brcmstb_i2c_xfer_bsc_data(struct brcmstb_i2c_dev *dev, > int no_ack = pmsg->flags & I2C_M_IGNORE_NAK; > > /* see if the transaction needs to check NACK conditions */ > - if (no_ack || len <= N_DATA_BYTES) { > + if (no_ack) { > cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD_NOACK > : CMD_WR_NOACK; > pi2creg->ctlhi_reg |= BSC_CTLHI_REG_IGNORE_ACK_MASK; > -- > 2.6.1 >
Hi Kamal, On Dec 1, 2015, at 12:37 AM, Wolfram Sang <wsa@the-dreams.de> wrote: > > On Wed, Oct 21, 2015 at 11:36:56AM +0900, Jaedon Shin wrote: >> Removes the condition of a message with under 32 bytes in length. The >> messages that do not require an ACK are I2C_M_IGNORE_NAK flag. > > Makes me wonder why it worked before? Kamal? > >> >> Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com> >> --- >> drivers/i2c/busses/i2c-brcmstb.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/i2c/busses/i2c-brcmstb.c b/drivers/i2c/busses/i2c-brcmstb.c >> index 2d7d155029dc..53eb8b0c9bad 100644 >> --- a/drivers/i2c/busses/i2c-brcmstb.c >> +++ b/drivers/i2c/busses/i2c-brcmstb.c >> @@ -330,7 +330,7 @@ static int brcmstb_i2c_xfer_bsc_data(struct brcmstb_i2c_dev *dev, >> int no_ack = pmsg->flags & I2C_M_IGNORE_NAK; >> >> /* see if the transaction needs to check NACK conditions */ >> - if (no_ack || len <= N_DATA_BYTES) { Could you please explain why have NOACK with smaller transfer size? I don't find any reason about NOACK when smaller size, and the driver always operates NOACK by "len <= xfersz". brcmstb_i2c_xfer(...) { int xfersz = brcmstb_i2c_get_xfersz(dev); ... bytes_to_xfer = min(len, xfersz); ... brcmstb_i2c_xfer_bsc_data(..., bytes_to_xfer, ...); ... I have a plan for v2 that has for BMIPS_GENERIC and this patch with the latest driver. Thanks! -- Jaedon >> + if (no_ack) { >> cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD_NOACK >> : CMD_WR_NOACK; >> pi2creg->ctlhi_reg |= BSC_CTLHI_REG_IGNORE_ACK_MASK; >> -- >> 2.6.1 >> -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Jaedon, Your change looks good to me. I agree that we do not need the size check. Kamal On Thu, Jul 14, 2016 at 12:15 AM, Jaedon Shin <jaedon.shin@gmail.com> wrote: > Hi Kamal, > > On Dec 1, 2015, at 12:37 AM, Wolfram Sang <wsa@the-dreams.de> wrote: >> >> On Wed, Oct 21, 2015 at 11:36:56AM +0900, Jaedon Shin wrote: >>> Removes the condition of a message with under 32 bytes in length. The >>> messages that do not require an ACK are I2C_M_IGNORE_NAK flag. >> >> Makes me wonder why it worked before? Kamal? >> >>> >>> Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com> >>> --- >>> drivers/i2c/busses/i2c-brcmstb.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/i2c/busses/i2c-brcmstb.c b/drivers/i2c/busses/i2c-brcmstb.c >>> index 2d7d155029dc..53eb8b0c9bad 100644 >>> --- a/drivers/i2c/busses/i2c-brcmstb.c >>> +++ b/drivers/i2c/busses/i2c-brcmstb.c >>> @@ -330,7 +330,7 @@ static int brcmstb_i2c_xfer_bsc_data(struct brcmstb_i2c_dev *dev, >>> int no_ack = pmsg->flags & I2C_M_IGNORE_NAK; >>> >>> /* see if the transaction needs to check NACK conditions */ >>> - if (no_ack || len <= N_DATA_BYTES) { > > Could you please explain why have NOACK with smaller transfer size? I don't find any > reason about NOACK when smaller size, and the driver always operates NOACK by "len <= xfersz". > > brcmstb_i2c_xfer(...) > { > int xfersz = brcmstb_i2c_get_xfersz(dev); > ... > bytes_to_xfer = min(len, xfersz); > ... > brcmstb_i2c_xfer_bsc_data(..., bytes_to_xfer, ...); > ... > > I have a plan for v2 that has for BMIPS_GENERIC and this patch with the latest driver. > > Thanks! > -- > Jaedon > >>> + if (no_ack) { >>> cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD_NOACK >>> : CMD_WR_NOACK; >>> pi2creg->ctlhi_reg |= BSC_CTLHI_REG_IGNORE_ACK_MASK; >>> -- >>> 2.6.1 >>> > -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> Your change looks good to me. I agree that we do not need the size check.
I read this as an ack, thanks. But how did it work before?
diff --git a/drivers/i2c/busses/i2c-brcmstb.c b/drivers/i2c/busses/i2c-brcmstb.c index 2d7d155029dc..53eb8b0c9bad 100644 --- a/drivers/i2c/busses/i2c-brcmstb.c +++ b/drivers/i2c/busses/i2c-brcmstb.c @@ -330,7 +330,7 @@ static int brcmstb_i2c_xfer_bsc_data(struct brcmstb_i2c_dev *dev, int no_ack = pmsg->flags & I2C_M_IGNORE_NAK; /* see if the transaction needs to check NACK conditions */ - if (no_ack || len <= N_DATA_BYTES) { + if (no_ack) { cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD_NOACK : CMD_WR_NOACK; pi2creg->ctlhi_reg |= BSC_CTLHI_REG_IGNORE_ACK_MASK;
Removes the condition of a message with under 32 bytes in length. The messages that do not require an ACK are I2C_M_IGNORE_NAK flag. Signed-off-by: Jaedon Shin <jaedon.shin@gmail.com> --- drivers/i2c/busses/i2c-brcmstb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)