| Message ID | 20241021062732.5592-3-kfting@nuvoton.com |
|---|---|
| State | New |
| Headers | show |
| Series | i2c: npcm: read/write operation, checkpatch | expand |
Dear Tyrone, Thank you for your patch. Am 21.10.24 um 08:27 schrieb Tyrone Ting: > From: Tyrone Ting <kfting@nuvoton.com> > > Store the client address earlier since it might get called in > the i2c_recover_bus() logic flow at the early stage of > npcm_i2c_master_xfer(). Thank you for the description. For the summary/title it’d be great, if you were more specific. For example: i2c: npcm: Assign client address earlier for `i2c_recover_bus()` It’d be great if you noted the commit, your patch fixes, so it’s clear since when the problem has been present. > Signed-off-by: Tyrone Ting <kfting@nuvoton.com> > Reviewed-by: Tali Perry <tali.perry1@gmail.com> > --- > drivers/i2c/busses/i2c-npcm7xx.c | 20 +++++++++++++++++++- > 1 file changed, 19 insertions(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c > index c96a25d37c14..a9a9b21f1f0b 100644 > --- a/drivers/i2c/busses/i2c-npcm7xx.c > +++ b/drivers/i2c/busses/i2c-npcm7xx.c > @@ -2155,6 +2155,16 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > } while (time_is_after_jiffies(time_left) && bus_busy); > > + /* > + * Previously, the 7-bit address was stored and being converted to > + * the address of event in the following call to npcm_i2c_master_start_xmit(). > + * > + * Since there are cases that the i2c_recover_bus() gets called at the > + * early stage of npcm_i2c_master_xfer(), the address of event is stored > + * and then used in the i2c_recover_bus(). > + */ > + bus->dest_addr = i2c_8bit_addr_from_msg(msg0); > + > /* > * Check the BER (bus error) state, when ber_state is true, it means that the module > * detects the bus error which is caused by some factor like that the electricity > @@ -2165,6 +2175,15 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > * bus is busy. > */ > if (bus_busy || bus->ber_state) { > + /* > + * Since the transfer might be a read operation, remove the I2C_M_RD flag > + * from the bus->dest_addr for the i2c_recover_bus() call later. > + * > + * The i2c_recover_bus() uses the address in a write direction to recover > + * the i2c bus if some error condition occurs. > + */ > + bus->dest_addr &= ~I2C_M_RD; > + > iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); > npcm_i2c_reset(bus); > i2c_recover_bus(adap); > @@ -2172,7 +2191,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > } > > npcm_i2c_init_params(bus); > - bus->dest_addr = slave_addr; > bus->msgs = msgs; > bus->msgs_num = num; > bus->cmd_err = 0; Kind regards, Paul
Hi Paul: Thank you for your comment. It'll be addressed in the next patch set. Paul Menzel <pmenzel@molgen.mpg.de> 於 2024年10月21日 週一 下午3:01寫道： > > Dear Tyrone, > > > Thank you for your patch. > > Am 21.10.24 um 08:27 schrieb Tyrone Ting: > > From: Tyrone Ting <kfting@nuvoton.com> > > > > Store the client address earlier since it might get called in > > the i2c_recover_bus() logic flow at the early stage of > > npcm_i2c_master_xfer(). > > Thank you for the description. For the summary/title it’d be great, if > you were more specific. For example: > > i2c: npcm: Assign client address earlier for `i2c_recover_bus()` > > It’d be great if you noted the commit, your patch fixes, so it’s clear > since when the problem has been present. > > > Signed-off-by: Tyrone Ting <kfting@nuvoton.com> > > Reviewed-by: Tali Perry <tali.perry1@gmail.com> > > --- > > drivers/i2c/busses/i2c-npcm7xx.c | 20 +++++++++++++++++++- > > 1 file changed, 19 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c > > index c96a25d37c14..a9a9b21f1f0b 100644 > > --- a/drivers/i2c/busses/i2c-npcm7xx.c > > +++ b/drivers/i2c/busses/i2c-npcm7xx.c > > @@ -2155,6 +2155,16 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > > > } while (time_is_after_jiffies(time_left) && bus_busy); > > > > + /* > > + * Previously, the 7-bit address was stored and being converted to > > + * the address of event in the following call to npcm_i2c_master_start_xmit(). > > + * > > + * Since there are cases that the i2c_recover_bus() gets called at the > > + * early stage of npcm_i2c_master_xfer(), the address of event is stored > > + * and then used in the i2c_recover_bus(). > > + */ > > + bus->dest_addr = i2c_8bit_addr_from_msg(msg0); > > + > > /* > > * Check the BER (bus error) state, when ber_state is true, it means that the module > > * detects the bus error which is caused by some factor like that the electricity > > @@ -2165,6 +2175,15 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > * bus is busy. > > */ > > if (bus_busy || bus->ber_state) { > > + /* > > + * Since the transfer might be a read operation, remove the I2C_M_RD flag > > + * from the bus->dest_addr for the i2c_recover_bus() call later. > > + * > > + * The i2c_recover_bus() uses the address in a write direction to recover > > + * the i2c bus if some error condition occurs. > > + */ > > + bus->dest_addr &= ~I2C_M_RD; > > + > > iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); > > npcm_i2c_reset(bus); > > i2c_recover_bus(adap); > > @@ -2172,7 +2191,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > } > > > > npcm_i2c_init_params(bus); > > - bus->dest_addr = slave_addr; > > bus->msgs = msgs; > > bus->msgs_num = num; > > bus->cmd_err = 0; > > > Kind regards, > > Paul Have a nice day. Regards, Tyrone
Hi Tyrone, On Tue, Oct 22, 2024 at 04:08:46PM +0800, Tyrone Ting wrote: > Hi Paul: > > Thank you for your comment. > > It'll be addressed in the next patch set. No need to resend, I can take care of it. Andi
Hi Tyrone, ... > + /* > + * Previously, the 7-bit address was stored and being converted to > + * the address of event in the following call to npcm_i2c_master_start_xmit(). Do we care how it was done previously? I think this is not a useful information as the code readers will se the code the way it is now, not the way it was done "previously". (there is a related comment at the end) > + * Since there are cases that the i2c_recover_bus() gets called at the > + * early stage of npcm_i2c_master_xfer(), the address of event is stored > + * and then used in the i2c_recover_bus(). I could rephrase this sentence to something like: /* * Store the address early in a global position to ensure it is * accessible for a potential call to i2c_recover_bus(). */ > + */ > + bus->dest_addr = i2c_8bit_addr_from_msg(msg0); > + > /* > * Check the BER (bus error) state, when ber_state is true, it means that the module > * detects the bus error which is caused by some factor like that the electricity > @@ -2165,6 +2175,15 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > * bus is busy. > */ > if (bus_busy || bus->ber_state) { > + /* > + * Since the transfer might be a read operation, remove the I2C_M_RD flag > + * from the bus->dest_addr for the i2c_recover_bus() call later. > + * > + * The i2c_recover_bus() uses the address in a write direction to recover > + * the i2c bus if some error condition occurs. > + */ > + bus->dest_addr &= ~I2C_M_RD; > + > iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); > npcm_i2c_reset(bus); > i2c_recover_bus(adap); > @@ -2172,7 +2191,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > } > > npcm_i2c_init_params(bus); > - bus->dest_addr = slave_addr; We can now get rid of slave_addr. It's just used in npcm_i2c_master_start_xmit(). Right? Andi > bus->msgs = msgs; > bus->msgs_num = num; > bus->cmd_err = 0; > -- > 2.34.1 >
HI Andi: Thank you for your help on this. Andi Shyti <andi.shyti@kernel.org> 於 2024年10月24日 週四 下午5:28寫道： > > Hi Tyrone, > > On Tue, Oct 22, 2024 at 04:08:46PM +0800, Tyrone Ting wrote: > > Hi Paul: > > > > Thank you for your comment. > > > > It'll be addressed in the next patch set. > > No need to resend, I can take care of it. > > Andi Have a nice day. Regards, Tyrone
Hi Andi: Thank you for your comments. Andi Shyti <andi.shyti@kernel.org> 於 2024年10月24日 週四 下午6:04寫道： > > Hi Tyrone, > > ... > > > + /* > > + * Previously, the 7-bit address was stored and being converted to > > + * the address of event in the following call to npcm_i2c_master_start_xmit(). > > Do we care how it was done previously? I think this is not a > useful information as the code readers will se the code the way > it is now, not the way it was done "previously". > Yes, it's not a useful information anymore. > (there is a related comment at the end) > > > + * Since there are cases that the i2c_recover_bus() gets called at the > > + * early stage of npcm_i2c_master_xfer(), the address of event is stored > > + * and then used in the i2c_recover_bus(). > > I could rephrase this sentence to something like: > > /* > * Store the address early in a global position to ensure it is > * accessible for a potential call to i2c_recover_bus(). > */ Understood. Thank you for your help on this. > > > + */ > > + bus->dest_addr = i2c_8bit_addr_from_msg(msg0); > > + > > /* > > * Check the BER (bus error) state, when ber_state is true, it means that the module > > * detects the bus error which is caused by some factor like that the electricity > > @@ -2165,6 +2175,15 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > * bus is busy. > > */ > > if (bus_busy || bus->ber_state) { > > + /* > > + * Since the transfer might be a read operation, remove the I2C_M_RD flag > > + * from the bus->dest_addr for the i2c_recover_bus() call later. > > + * > > + * The i2c_recover_bus() uses the address in a write direction to recover > > + * the i2c bus if some error condition occurs. > > + */ > > + bus->dest_addr &= ~I2C_M_RD; > > + > > iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); > > npcm_i2c_reset(bus); > > i2c_recover_bus(adap); > > @@ -2172,7 +2191,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > } > > > > npcm_i2c_init_params(bus); > > - bus->dest_addr = slave_addr; > > We can now get rid of slave_addr. It's just used in > npcm_i2c_master_start_xmit(). Right? Yes, slave_addr is just used as the link https://github.com/torvalds/linux/blob/master/drivers/i2c/busses/i2c-npcm7xx.c#L2182 suggests with this patch. > > Andi > > > bus->msgs = msgs; > > bus->msgs_num = num; > > bus->cmd_err = 0; > > -- > > 2.34.1 > > Thank you. Regards, Tyrone
Hi Andi: Sorry to bother you. May I have your comments about my feedback on these patches? It'll be great to know if I need to prepare the next patch set for reviewing. Tyrone Ting <warp5tw@gmail.com> 於 2024年10月25日 週五 上午9:43寫道： > > Hi Andi: > > Thank you for your comments. > > Andi Shyti <andi.shyti@kernel.org> 於 2024年10月24日 週四 下午6:04寫道： > > > > Hi Tyrone, > > > > ... > > > > > + /* > > > + * Previously, the 7-bit address was stored and being converted to > > > + * the address of event in the following call to npcm_i2c_master_start_xmit(). > > > > Do we care how it was done previously? I think this is not a > > useful information as the code readers will se the code the way > > it is now, not the way it was done "previously". > > > > Yes, it's not a useful information anymore. > > > (there is a related comment at the end) > > > > > + * Since there are cases that the i2c_recover_bus() gets called at the > > > + * early stage of npcm_i2c_master_xfer(), the address of event is stored > > > + * and then used in the i2c_recover_bus(). > > > > I could rephrase this sentence to something like: > > > > /* > > * Store the address early in a global position to ensure it is > > * accessible for a potential call to i2c_recover_bus(). > > */ > > Understood. Thank you for your help on this. > > > > > > + */ > > > + bus->dest_addr = i2c_8bit_addr_from_msg(msg0); > > > + > > > /* > > > * Check the BER (bus error) state, when ber_state is true, it means that the module > > > * detects the bus error which is caused by some factor like that the electricity > > > @@ -2165,6 +2175,15 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > > * bus is busy. > > > */ > > > if (bus_busy || bus->ber_state) { > > > + /* > > > + * Since the transfer might be a read operation, remove the I2C_M_RD flag > > > + * from the bus->dest_addr for the i2c_recover_bus() call later. > > > + * > > > + * The i2c_recover_bus() uses the address in a write direction to recover > > > + * the i2c bus if some error condition occurs. > > > + */ > > > + bus->dest_addr &= ~I2C_M_RD; > > > + > > > iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); > > > npcm_i2c_reset(bus); > > > i2c_recover_bus(adap); > > > @@ -2172,7 +2191,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > > } > > > > > > npcm_i2c_init_params(bus); > > > - bus->dest_addr = slave_addr; > > > > We can now get rid of slave_addr. It's just used in > > npcm_i2c_master_start_xmit(). Right? > > Yes, slave_addr is just used as the link > https://github.com/torvalds/linux/blob/master/drivers/i2c/busses/i2c-npcm7xx.c#L2182 > suggests with this patch. > > > > > Andi > > > > > bus->msgs = msgs; > > > bus->msgs_num = num; > > > bus->cmd_err = 0; > > > -- > > > 2.34.1 > > > > > Thank you. > > Regards, > Tyrone Have a nice day. Thank you. Regards, Tyrone
Hi Andi: May I have your comments about my feedback on these patches? Tyrone Ting <warp5tw@gmail.com> 於 2024年10月29日 週二 下午4:50寫道： > > Hi Andi: > > Sorry to bother you. > > May I have your comments about my feedback on these patches? > > It'll be great to know if I need to prepare the next patch set for reviewing. > > Tyrone Ting <warp5tw@gmail.com> 於 2024年10月25日 週五 上午9:43寫道： > > > > Hi Andi: > > > > Thank you for your comments. > > > > Andi Shyti <andi.shyti@kernel.org> 於 2024年10月24日 週四 下午6:04寫道： > > > > > > Hi Tyrone, > > > > > > ... > > > > > > > + /* > > > > + * Previously, the 7-bit address was stored and being converted to > > > > + * the address of event in the following call to npcm_i2c_master_start_xmit(). > > > > > > Do we care how it was done previously? I think this is not a > > > useful information as the code readers will se the code the way > > > it is now, not the way it was done "previously". > > > > > > > Yes, it's not a useful information anymore. > > > > > (there is a related comment at the end) > > > > > > > + * Since there are cases that the i2c_recover_bus() gets called at the > > > > + * early stage of npcm_i2c_master_xfer(), the address of event is stored > > > > + * and then used in the i2c_recover_bus(). > > > > > > I could rephrase this sentence to something like: > > > > > > /* > > > * Store the address early in a global position to ensure it is > > > * accessible for a potential call to i2c_recover_bus(). > > > */ > > > > Understood. Thank you for your help on this. > > > > > > > > > + */ > > > > + bus->dest_addr = i2c_8bit_addr_from_msg(msg0); > > > > + > > > > /* > > > > * Check the BER (bus error) state, when ber_state is true, it means that the module > > > > * detects the bus error which is caused by some factor like that the electricity > > > > @@ -2165,6 +2175,15 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > > > * bus is busy. > > > > */ > > > > if (bus_busy || bus->ber_state) { > > > > + /* > > > > + * Since the transfer might be a read operation, remove the I2C_M_RD flag > > > > + * from the bus->dest_addr for the i2c_recover_bus() call later. > > > > + * > > > > + * The i2c_recover_bus() uses the address in a write direction to recover > > > > + * the i2c bus if some error condition occurs. > > > > + */ > > > > + bus->dest_addr &= ~I2C_M_RD; > > > > + > > > > iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); > > > > npcm_i2c_reset(bus); > > > > i2c_recover_bus(adap); > > > > @@ -2172,7 +2191,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > > > } > > > > > > > > npcm_i2c_init_params(bus); > > > > - bus->dest_addr = slave_addr; > > > > > > We can now get rid of slave_addr. It's just used in > > > npcm_i2c_master_start_xmit(). Right? > > > > Yes, slave_addr is just used as the link > > https://github.com/torvalds/linux/blob/master/drivers/i2c/busses/i2c-npcm7xx.c#L2182 > > suggests with this patch. > > > > > > > > Andi > > > > > > > bus->msgs = msgs; > > > > bus->msgs_num = num; > > > > bus->cmd_err = 0; > > > > -- > > > > 2.34.1 > > > > > > > > Thank you. > > > > Regards, > > Tyrone > > Have a nice day. > > Thank you. > > Regards, > Tyrone Thank you. Regards, Tyrone
Hi Andi: Thank you for your reply. Andi Shyti <andi.shyti@kernel.org> 於 2024年11月20日 週三 上午6:22寫道： > > Hi Tyrone, > > Sorry for the late reply! > > ... > > > > > @@ -2172,7 +2191,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > > > } > > > > > > > > npcm_i2c_init_params(bus); > > > > - bus->dest_addr = slave_addr; > > > > > > We can now get rid of slave_addr. It's just used in > > > npcm_i2c_master_start_xmit(). Right? > > > > Yes, slave_addr is just used as the link > > https://github.com/torvalds/linux/blob/master/drivers/i2c/busses/i2c-npcm7xx.c#L2182 > > suggests with this patch. > > What I mean is that slave_addr now is completely unused. We > declare it, we initialize it to msg0->addr and it stays like > this. > > What I'm suggesting is to remove it completely. > Sorry that I might not describe it clearly in previous discussion thread. slave_addr is passed to npcm_i2c_master_start_xmit() as https://github.com/torvalds/linux/blob/master/drivers/i2c/busses/i2c-npcm7xx.c#L2182 suggests. If slave_addr is removed, may I use "(bus->dest_addr &= ~I2C_M_RD)" to replace the slave_addr parameter to npcm_i2c_master_start_xmit()? > Andi Thank you. Regards, Tyrone
diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c index c96a25d37c14..a9a9b21f1f0b 100644 --- a/drivers/i2c/busses/i2c-npcm7xx.c +++ b/drivers/i2c/busses/i2c-npcm7xx.c @@ -2155,6 +2155,16 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, } while (time_is_after_jiffies(time_left) && bus_busy); + /* + * Previously, the 7-bit address was stored and being converted to + * the address of event in the following call to npcm_i2c_master_start_xmit(). + * + * Since there are cases that the i2c_recover_bus() gets called at the + * early stage of npcm_i2c_master_xfer(), the address of event is stored + * and then used in the i2c_recover_bus(). + */ + bus->dest_addr = i2c_8bit_addr_from_msg(msg0); + /* * Check the BER (bus error) state, when ber_state is true, it means that the module * detects the bus error which is caused by some factor like that the electricity @@ -2165,6 +2175,15 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, * bus is busy. */ if (bus_busy || bus->ber_state) { + /* + * Since the transfer might be a read operation, remove the I2C_M_RD flag + * from the bus->dest_addr for the i2c_recover_bus() call later. + * + * The i2c_recover_bus() uses the address in a write direction to recover + * the i2c bus if some error condition occurs. + */ + bus->dest_addr &= ~I2C_M_RD; + iowrite8(NPCM_I2CCST_BB, bus->reg + NPCM_I2CCST); npcm_i2c_reset(bus); i2c_recover_bus(adap); @@ -2172,7 +2191,6 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, } npcm_i2c_init_params(bus); - bus->dest_addr = slave_addr; bus->msgs = msgs; bus->msgs_num = num; bus->cmd_err = 0;