| Message ID | 54FF2631.9050006@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, 2015-03-10 at 22:43 +0530, Neelesh Gupta wrote: > I tested the i2c opal driver after updating the patch as below. > Basically I think we can also support write-then-{read/write} > for the number of messages = 2. > Ben, any issues if we support both write plus read/write in the > opal driver ? Nope, in fact it's a good idea, I found myself having to expoes such an interface to some userspace tool of ours. However... > diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c > index 16f90b1..85412ba 100644 > --- a/drivers/i2c/busses/i2c-opal.c > +++ b/drivers/i2c/busses/i2c-opal.c > @@ -104,18 +104,8 @@ static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf)); > break; > case 2: > - /* For two messages, we basically support only simple > - * smbus transactions of a write plus a read. We might > - * want to allow also two writes but we'd have to bounce > - * the data into a single buffer. > - */ > - if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD)) > - return -EOPNOTSUPP; Don't we still want to enforce that the first message is a write ? Somebody may not be looking at the quirks... > - if (msgs[0].len > 4) > - return -EOPNOTSUPP; And that the len is supported... > - if (msgs[0].addr != msgs[1].addr) > - return -EOPNOTSUPP; Same... Ie, the quirk indicates to the callers what we support, but we should still check that we aren't called with something that doesn't match. > - req.type = OPAL_I2C_SM_READ; > + req.type = (msgs[1].flags & I2C_M_RD) ? > + OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE; > req.addr = cpu_to_be16(msgs[0].addr); > req.subaddr_sz = msgs[0].len; > for (i = 0; i < msgs[0].len; i++) > @@ -210,6 +200,11 @@ static const struct i2c_algorithm i2c_opal_algo = { > .functionality = i2c_opal_func, > }; > > +static struct i2c_adapter_quirks i2c_opal_quirks = { > + .flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | I2C_AQ_COMB_SAME_ADDR, > + .max_comb_1st_msg_len = 4, > +}; > + > static int i2c_opal_probe(struct platform_device *pdev) > { > struct i2c_adapter *adapter; > @@ -232,6 +227,7 @@ static int i2c_opal_probe(struct platform_device *pdev) > > adapter->algo = &i2c_opal_algo; > adapter->algo_data = (void *)(unsigned long)opal_id; > + adapter->quirks = &i2c_opal_quirks; > adapter->dev.parent = &pdev->dev; > adapter->dev.of_node = of_node_get(pdev->dev.of_node); > pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL); > > > > On 02/25/2015 09:31 PM, Wolfram Sang wrote: > > From: Wolfram Sang <wsa+renesas@sang-engineering.com> > > > > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> > > --- > > drivers/i2c/busses/i2c-opal.c | 22 +++++++++++----------- > > 1 file changed, 11 insertions(+), 11 deletions(-) > > > > diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c > > index 16f90b1a750894..b2788ecad5b3cb 100644 > > --- a/drivers/i2c/busses/i2c-opal.c > > +++ b/drivers/i2c/busses/i2c-opal.c > > @@ -104,17 +104,6 @@ static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > > req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf)); > > break; > > case 2: > > - /* For two messages, we basically support only simple > > - * smbus transactions of a write plus a read. We might > > - * want to allow also two writes but we'd have to bounce > > - * the data into a single buffer. > > - */ > > - if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD)) > > - return -EOPNOTSUPP; > > - if (msgs[0].len > 4) > > - return -EOPNOTSUPP; > > - if (msgs[0].addr != msgs[1].addr) > > - return -EOPNOTSUPP; > > req.type = OPAL_I2C_SM_READ; > > req.addr = cpu_to_be16(msgs[0].addr); > > req.subaddr_sz = msgs[0].len; > > @@ -210,6 +199,16 @@ static const struct i2c_algorithm i2c_opal_algo = { > > .functionality = i2c_opal_func, > > }; > > > > +/* For two messages, we basically support only simple > > + * smbus transactions of a write plus a read. We might > > + * want to allow also two writes but we'd have to bounce > > + * the data into a single buffer. > > + */ > > +static struct i2c_adapter_quirks i2c_opal_quirks = { > > + .flags = I2C_AQ_COMB_WRITE_THEN_READ, > > + .max_comb_1st_msg_len = 4, > > +}; > > + > > static int i2c_opal_probe(struct platform_device *pdev) > > { > > struct i2c_adapter *adapter; > > @@ -232,6 +231,7 @@ static int i2c_opal_probe(struct platform_device *pdev) > > > > adapter->algo = &i2c_opal_algo; > > adapter->algo_data = (void *)(unsigned long)opal_id; > > + adapter->quirks = &i2c_opal_quirks; > > adapter->dev.parent = &pdev->dev; > > adapter->dev.of_node = of_node_get(pdev->dev.of_node); > > pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL);
On 03/11/2015 04:42 AM, Benjamin Herrenschmidt wrote: > On Tue, 2015-03-10 at 22:43 +0530, Neelesh Gupta wrote: >> I tested the i2c opal driver after updating the patch as below. >> Basically I think we can also support write-then-{read/write} >> for the number of messages = 2. >> Ben, any issues if we support both write plus read/write in the >> opal driver ? > Nope, in fact it's a good idea, I found myself having to expoes such > an interface to some userspace tool of ours. > > However... > >> diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c >> index 16f90b1..85412ba 100644 >> --- a/drivers/i2c/busses/i2c-opal.c >> +++ b/drivers/i2c/busses/i2c-opal.c >> @@ -104,18 +104,8 @@ static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, >> req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf)); >> break; >> case 2: >> - /* For two messages, we basically support only simple >> - * smbus transactions of a write plus a read. We might >> - * want to allow also two writes but we'd have to bounce >> - * the data into a single buffer. >> - */ >> - if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD)) >> - return -EOPNOTSUPP; > Don't we still want to enforce that the first message is a write ? > Somebody may not be looking at the quirks... > >> - if (msgs[0].len > 4) >> - return -EOPNOTSUPP; > And that the len is supported... > >> - if (msgs[0].addr != msgs[1].addr) >> - return -EOPNOTSUPP; > Same... > > Ie, the quirk indicates to the callers what we support, but we should > still check that we aren't called with something that doesn't match. Quirk *also* return error to the user if any of the conditions mismatch with what we have indicated through the quriks structure... I think we can't land up here by-passing the check for quirks so above checks are duplicated here.. Neelesh. > >> - req.type = OPAL_I2C_SM_READ; >> + req.type = (msgs[1].flags & I2C_M_RD) ? >> + OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE; >> req.addr = cpu_to_be16(msgs[0].addr); >> req.subaddr_sz = msgs[0].len; >> for (i = 0; i < msgs[0].len; i++) >> @@ -210,6 +200,11 @@ static const struct i2c_algorithm i2c_opal_algo = { >> .functionality = i2c_opal_func, >> }; >> >> +static struct i2c_adapter_quirks i2c_opal_quirks = { >> + .flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | I2C_AQ_COMB_SAME_ADDR, >> + .max_comb_1st_msg_len = 4, >> +}; >> + >> static int i2c_opal_probe(struct platform_device *pdev) >> { >> struct i2c_adapter *adapter; >> @@ -232,6 +227,7 @@ static int i2c_opal_probe(struct platform_device *pdev) >> >> adapter->algo = &i2c_opal_algo; >> adapter->algo_data = (void *)(unsigned long)opal_id; >> + adapter->quirks = &i2c_opal_quirks; >> adapter->dev.parent = &pdev->dev; >> adapter->dev.of_node = of_node_get(pdev->dev.of_node); >> pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL); >> >> >> >> On 02/25/2015 09:31 PM, Wolfram Sang wrote: >>> From: Wolfram Sang <wsa+renesas@sang-engineering.com> >>> >>> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> >>> --- >>> drivers/i2c/busses/i2c-opal.c | 22 +++++++++++----------- >>> 1 file changed, 11 insertions(+), 11 deletions(-) >>> >>> diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c >>> index 16f90b1a750894..b2788ecad5b3cb 100644 >>> --- a/drivers/i2c/busses/i2c-opal.c >>> +++ b/drivers/i2c/busses/i2c-opal.c >>> @@ -104,17 +104,6 @@ static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, >>> req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf)); >>> break; >>> case 2: >>> - /* For two messages, we basically support only simple >>> - * smbus transactions of a write plus a read. We might >>> - * want to allow also two writes but we'd have to bounce >>> - * the data into a single buffer. >>> - */ >>> - if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD)) >>> - return -EOPNOTSUPP; >>> - if (msgs[0].len > 4) >>> - return -EOPNOTSUPP; >>> - if (msgs[0].addr != msgs[1].addr) >>> - return -EOPNOTSUPP; >>> req.type = OPAL_I2C_SM_READ; >>> req.addr = cpu_to_be16(msgs[0].addr); >>> req.subaddr_sz = msgs[0].len; >>> @@ -210,6 +199,16 @@ static const struct i2c_algorithm i2c_opal_algo = { >>> .functionality = i2c_opal_func, >>> }; >>> >>> +/* For two messages, we basically support only simple >>> + * smbus transactions of a write plus a read. We might >>> + * want to allow also two writes but we'd have to bounce >>> + * the data into a single buffer. >>> + */ >>> +static struct i2c_adapter_quirks i2c_opal_quirks = { >>> + .flags = I2C_AQ_COMB_WRITE_THEN_READ, >>> + .max_comb_1st_msg_len = 4, >>> +}; >>> + >>> static int i2c_opal_probe(struct platform_device *pdev) >>> { >>> struct i2c_adapter *adapter; >>> @@ -232,6 +231,7 @@ static int i2c_opal_probe(struct platform_device *pdev) >>> >>> adapter->algo = &i2c_opal_algo; >>> adapter->algo_data = (void *)(unsigned long)opal_id; >>> + adapter->quirks = &i2c_opal_quirks; >>> adapter->dev.parent = &pdev->dev; >>> adapter->dev.of_node = of_node_get(pdev->dev.of_node); >>> pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL); >
> I think we can't land up here by-passing the check for quirks so above > checks are duplicated here.. True. So, as Ben seems OK with write-then-anything, can you send me your changes as an incremental patch to mine with your Signed-off, please? Thanks, Wolfram
diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c index 16f90b1..85412ba 100644 --- a/drivers/i2c/busses/i2c-opal.c +++ b/drivers/i2c/busses/i2c-opal.c @@ -104,18 +104,8 @@ static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf)); break; case 2: - /* For two messages, we basically support only simple - * smbus transactions of a write plus a read. We might - * want to allow also two writes but we'd have to bounce - * the data into a single buffer. - */ - if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD)) - return -EOPNOTSUPP; - if (msgs[0].len > 4) - return -EOPNOTSUPP; - if (msgs[0].addr != msgs[1].addr) - return -EOPNOTSUPP; - req.type = OPAL_I2C_SM_READ; + req.type = (msgs[1].flags & I2C_M_RD) ? + OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE; req.addr = cpu_to_be16(msgs[0].addr); req.subaddr_sz = msgs[0].len; for (i = 0; i < msgs[0].len; i++) @@ -210,6 +200,11 @@ static const struct i2c_algorithm i2c_opal_algo = { .functionality = i2c_opal_func, }; +static struct i2c_adapter_quirks i2c_opal_quirks = { + .flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | I2C_AQ_COMB_SAME_ADDR, + .max_comb_1st_msg_len = 4, +}; + static int i2c_opal_probe(struct platform_device *pdev) { struct i2c_adapter *adapter; @@ -232,6 +227,7 @@ static int i2c_opal_probe(struct platform_device *pdev) adapter->algo = &i2c_opal_algo; adapter->algo_data = (void *)(unsigned long)opal_id; + adapter->quirks = &i2c_opal_quirks; adapter->dev.parent = &pdev->dev; adapter->dev.of_node = of_node_get(pdev->dev.of_node); pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL);
I tested the i2c opal driver after updating the patch as below. Basically I think we can also support write-then-{read/write} for the number of messages = 2. Ben, any issues if we support both write plus read/write in the opal driver ? Regards, Neelesh drivers/i2c/busses/i2c-opal.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) On 02/25/2015 09:31 PM, Wolfram Sang wrote: > From: Wolfram Sang <wsa+renesas@sang-engineering.com> > > Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> > --- > drivers/i2c/busses/i2c-opal.c | 22 +++++++++++----------- > 1 file changed, 11 insertions(+), 11 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c > index 16f90b1a750894..b2788ecad5b3cb 100644 > --- a/drivers/i2c/busses/i2c-opal.c > +++ b/drivers/i2c/busses/i2c-opal.c > @@ -104,17 +104,6 @@ static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, > req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf)); > break; > case 2: > - /* For two messages, we basically support only simple > - * smbus transactions of a write plus a read. We might > - * want to allow also two writes but we'd have to bounce > - * the data into a single buffer. > - */ > - if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD)) > - return -EOPNOTSUPP; > - if (msgs[0].len > 4) > - return -EOPNOTSUPP; > - if (msgs[0].addr != msgs[1].addr) > - return -EOPNOTSUPP; > req.type = OPAL_I2C_SM_READ; > req.addr = cpu_to_be16(msgs[0].addr); > req.subaddr_sz = msgs[0].len; > @@ -210,6 +199,16 @@ static const struct i2c_algorithm i2c_opal_algo = { > .functionality = i2c_opal_func, > }; > > +/* For two messages, we basically support only simple > + * smbus transactions of a write plus a read. We might > + * want to allow also two writes but we'd have to bounce > + * the data into a single buffer. > + */ > +static struct i2c_adapter_quirks i2c_opal_quirks = { > + .flags = I2C_AQ_COMB_WRITE_THEN_READ, > + .max_comb_1st_msg_len = 4, > +}; > + > static int i2c_opal_probe(struct platform_device *pdev) > { > struct i2c_adapter *adapter; > @@ -232,6 +231,7 @@ static int i2c_opal_probe(struct platform_device *pdev) > > adapter->algo = &i2c_opal_algo; > adapter->algo_data = (void *)(unsigned long)opal_id; > + adapter->quirks = &i2c_opal_quirks; > adapter->dev.parent = &pdev->dev; > adapter->dev.of_node = of_node_get(pdev->dev.of_node); > pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL);