| Message ID | 20200905204151.25343-17-digetx@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Improvements for Tegra I2C driver | expand |
On Sat, Sep 05, 2020 at 11:41:36PM +0300, Dmitry Osipenko wrote: > The "dma" variable of tegra_i2c_xfer_msg() function doesn't bring much in > regards to readability and generation of the code, hence let's remove it > to clean up code a tad. [...] > --- a/drivers/i2c/busses/i2c-tegra.c > +++ b/drivers/i2c/busses/i2c-tegra.c [...] > + if (i2c_dev->is_curr_dma_xfer) { [...] In this case I like the previous code better: just because there are less letters to read. :-) Best Regards, Michał Mirosław
06.09.2020 01:23, Michał Mirosław пишет: > On Sat, Sep 05, 2020 at 11:41:36PM +0300, Dmitry Osipenko wrote: >> The "dma" variable of tegra_i2c_xfer_msg() function doesn't bring much in >> regards to readability and generation of the code, hence let's remove it >> to clean up code a tad. > [...] >> --- a/drivers/i2c/busses/i2c-tegra.c >> +++ b/drivers/i2c/busses/i2c-tegra.c > [...] >> + if (i2c_dev->is_curr_dma_xfer) { > [...] > > In this case I like the previous code better: just because there are > less letters to read. :-) Besides readability, I also don't like much that the is_curr_dma_xfer is initialized in tegra_i2c_xfer_msg() and then could be overridden by tegra_i2c_config_fifo_trig(). In a result the "dma" variable confuses me since it's not instantly obvious why it's set after tegra_i2c_config_fifo_trig(). Looking at the final result, I think it's better to have the variable removed. It makes code more consistent, IMO.
On Sun, Sep 06, 2020 at 01:36:20AM +0300, Dmitry Osipenko wrote: > 06.09.2020 01:23, Michał Mirosław пишет: > > On Sat, Sep 05, 2020 at 11:41:36PM +0300, Dmitry Osipenko wrote: > >> The "dma" variable of tegra_i2c_xfer_msg() function doesn't bring much in > >> regards to readability and generation of the code, hence let's remove it > >> to clean up code a tad. > > [...] > >> --- a/drivers/i2c/busses/i2c-tegra.c > >> +++ b/drivers/i2c/busses/i2c-tegra.c > > [...] > >> + if (i2c_dev->is_curr_dma_xfer) { > > [...] > > > > In this case I like the previous code better: just because there are > > less letters to read. :-) > > Besides readability, I also don't like much that the is_curr_dma_xfer is > initialized in tegra_i2c_xfer_msg() and then could be overridden by > tegra_i2c_config_fifo_trig(). In a result the "dma" variable confuses me > since it's not instantly obvious why it's set after > tegra_i2c_config_fifo_trig(). > > Looking at the final result, I think it's better to have the variable > removed. It makes code more consistent, IMO. If it could be changed in some callee, then indeed it is better. In this case I would include this information in the commit msg. Best Regards, Michał Mirosław
06.09.2020 01:49, Michał Mirosław пишет: > On Sun, Sep 06, 2020 at 01:36:20AM +0300, Dmitry Osipenko wrote: >> 06.09.2020 01:23, Michał Mirosław пишет: >>> On Sat, Sep 05, 2020 at 11:41:36PM +0300, Dmitry Osipenko wrote: >>>> The "dma" variable of tegra_i2c_xfer_msg() function doesn't bring much in >>>> regards to readability and generation of the code, hence let's remove it >>>> to clean up code a tad. >>> [...] >>>> --- a/drivers/i2c/busses/i2c-tegra.c >>>> +++ b/drivers/i2c/busses/i2c-tegra.c >>> [...] >>>> + if (i2c_dev->is_curr_dma_xfer) { >>> [...] >>> >>> In this case I like the previous code better: just because there are >>> less letters to read. :-) >> >> Besides readability, I also don't like much that the is_curr_dma_xfer is >> initialized in tegra_i2c_xfer_msg() and then could be overridden by >> tegra_i2c_config_fifo_trig(). In a result the "dma" variable confuses me >> since it's not instantly obvious why it's set after >> tegra_i2c_config_fifo_trig(). >> >> Looking at the final result, I think it's better to have the variable >> removed. It makes code more consistent, IMO. > > If it could be changed in some callee, then indeed it is better. In this > case I would include this information in the commit msg. That's a good suggestion, thanks.
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index f69587ca163b..f52046593b8b 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -1155,7 +1155,6 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, size_t xfer_size; u32 *buffer = NULL; int err = 0; - bool dma; u16 xfer_time = 100; err = tegra_i2c_flush_fifos(i2c_dev); @@ -1178,7 +1177,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, i2c_dev->dma_buf && !i2c_dev->is_curr_atomic_xfer; tegra_i2c_config_fifo_trig(i2c_dev, xfer_size); - dma = i2c_dev->is_curr_dma_xfer; + /* * Transfer time in mSec = Total bits / transfer rate * Total bits = 9 bits per byte (including ACK bit) + Start & stop bits @@ -1188,7 +1187,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST; tegra_i2c_unmask_irq(i2c_dev, int_mask); - if (dma) { + if (i2c_dev->is_curr_dma_xfer) { if (i2c_dev->msg_read) { dma_sync_single_for_device(i2c_dev->dev, i2c_dev->dma_phys, @@ -1216,13 +1215,13 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, PACKET_HEADER0_PROTOCOL_I2C) | FIELD_PREP(PACKET_HEADER0_CONT_ID, i2c_dev->cont_id) | FIELD_PREP(PACKET_HEADER0_PACKET_ID, 1); - if (dma && !i2c_dev->msg_read) + if (i2c_dev->is_curr_dma_xfer && !i2c_dev->msg_read) *buffer++ = packet_header; else i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); packet_header = msg->len - 1; - if (dma && !i2c_dev->msg_read) + if (i2c_dev->is_curr_dma_xfer && !i2c_dev->msg_read) *buffer++ = packet_header; else i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); @@ -1242,13 +1241,13 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, packet_header |= I2C_HEADER_CONT_ON_NAK; if (msg->flags & I2C_M_RD) packet_header |= I2C_HEADER_READ; - if (dma && !i2c_dev->msg_read) + if (i2c_dev->is_curr_dma_xfer && !i2c_dev->msg_read) *buffer++ = packet_header; else i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO); if (!i2c_dev->msg_read) { - if (dma) { + if (i2c_dev->is_curr_dma_xfer) { memcpy(buffer, msg->buf, msg->len); dma_sync_single_for_device(i2c_dev->dev, i2c_dev->dma_phys, @@ -1268,7 +1267,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, if (i2c_dev->hw->has_per_pkt_xfer_complete_irq) int_mask |= I2C_INT_PACKET_XFER_COMPLETE; - if (!dma) { + if (!i2c_dev->is_curr_dma_xfer) { if (msg->flags & I2C_M_RD) int_mask |= I2C_INT_RX_FIFO_DATA_REQ; else if (i2c_dev->msg_buf_remaining) @@ -1279,7 +1278,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n", i2c_readl(i2c_dev, I2C_INT_MASK)); - if (dma) { + if (i2c_dev->is_curr_dma_xfer) { time_left = tegra_i2c_wait_completion_timeout( i2c_dev, &i2c_dev->dma_complete, xfer_time);
The "dma" variable of tegra_i2c_xfer_msg() function doesn't bring much in regards to readability and generation of the code, hence let's remove it to clean up code a tad. Signed-off-by: Dmitry Osipenko <digetx@gmail.com> --- drivers/i2c/busses/i2c-tegra.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-)