| Message ID | 1435085899-11017-2-git-send-email-benjamin.tissoires@redhat.com |
|---|---|
| State | Superseded |
| Headers | show |
Hi Benjamin, On Tue, 23 Jun 2015 14:58:18 -0400, Benjamin Tissoires wrote: > SMBus Host Notify allows a slave device to act as a master on a bus to > notify the host of an interrupt. The functionality is directly implemented > in the firmware so we just export a toggle function and rely on the > adapter to actually support this. Why does it need to be toggled? I mean, if the controller supports it, why don't we just enable the feature all the time? > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> > --- > Documentation/i2c/smbus-protocol | 4 ++++ > drivers/i2c/i2c-core.c | 26 ++++++++++++++++++++++++++ > include/linux/i2c.h | 8 ++++++++ > include/uapi/linux/i2c.h | 1 + > 4 files changed, 39 insertions(+) > > diff --git a/Documentation/i2c/smbus-protocol b/Documentation/i2c/smbus-protocol > index 6012b12..af4e4b9 100644 > --- a/Documentation/i2c/smbus-protocol > +++ b/Documentation/i2c/smbus-protocol > @@ -199,6 +199,10 @@ alerting device's address. > > [S] [HostAddr] [Wr] A [DevAddr] A [DataLow] A [DataHigh] A [P] > > +I2C drivers for devices which can trigger SMBus Host Notify should call > +i2c_smbus_toggle_host_notify() to enable SMBUS Host Notify on the adapter > +and implement the optional alert() callback. > + > > Packet Error Checking (PEC) > =========================== > diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c > index 987c124..eaaf5b0 100644 > --- a/drivers/i2c/i2c-core.c > +++ b/drivers/i2c/i2c-core.c > @@ -2959,6 +2959,32 @@ int i2c_slave_unregister(struct i2c_client *client) > EXPORT_SYMBOL_GPL(i2c_slave_unregister); > #endif > > +int i2c_smbus_toggle_host_notify(struct i2c_client *client, bool state) > +{ > + int ret; > + > + if (!client) > + return -EINVAL; > + > + if (!(client->flags & I2C_CLIENT_TEN)) { > + /* Enforce stricter address checking */ > + ret = i2c_check_addr_validity(client->addr); > + if (ret) > + return ret; > + } > + > + if (!client->adapter->algo->toggle_smbus_host_notify) > + return -EOPNOTSUPP; > + > + i2c_lock_adapter(client->adapter); > + ret = client->adapter->algo->toggle_smbus_host_notify(client->adapter, > + state); > + i2c_unlock_adapter(client->adapter); > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(i2c_smbus_toggle_host_notify); > + As this is an SMBus feature, can't it go to drivers/i2c/i2c-smbus.c? > MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); > MODULE_DESCRIPTION("I2C-Bus main module"); > MODULE_LICENSE("GPL"); > diff --git a/include/linux/i2c.h b/include/linux/i2c.h > index e83a738..7ffc970 100644 > --- a/include/linux/i2c.h > +++ b/include/linux/i2c.h > @@ -177,6 +177,8 @@ struct i2c_driver { > * The format and meaning of the data value depends on the protocol. > * For the SMBus alert protocol, there is a single bit of data passed > * as the alert response's low bit ("event flag"). > + * For the SMBus Host Notify protocol, the data corresponds to the > + * 16-bits payload data reported by the external device. 16-bit (no s) > */ > void (*alert)(struct i2c_client *, unsigned int data); > > @@ -270,6 +272,9 @@ static inline int i2c_slave_event(struct i2c_client *client, > } > #endif > > + No double blank lines in source code please. > +extern int i2c_smbus_toggle_host_notify(struct i2c_client *client, bool state); > + > /** > * struct i2c_board_info - template for device creation > * @type: chip type, to initialize i2c_client.name > @@ -378,6 +383,8 @@ i2c_register_board_info(int busnum, struct i2c_board_info const *info, > * from the I2C_FUNC_* flags. > * @reg_slave: Register given client to I2C slave mode of this adapter > * @unreg_slave: Unregister given client from I2C slave mode of this adapter > + * @toggle_smbus_host_notify: toggle the SMBus Host Notify support of this > + * adapter. > * > * The following structs are for those who like to implement new bus drivers: > * i2c_algorithm is the interface to a class of hardware solutions which can > @@ -408,6 +415,7 @@ struct i2c_algorithm { > int (*reg_slave)(struct i2c_client *client); > int (*unreg_slave)(struct i2c_client *client); > #endif > + int (*toggle_smbus_host_notify)(struct i2c_adapter *adap, bool state); Please put it after u32 (*functionality), so that the field offsets do not depend on configuration options. > }; > > /** > diff --git a/include/uapi/linux/i2c.h b/include/uapi/linux/i2c.h > index 0e949cb..c72708e 100644 > --- a/include/uapi/linux/i2c.h > +++ b/include/uapi/linux/i2c.h > @@ -100,6 +100,7 @@ struct i2c_msg { > #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000 > #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */ > #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */ > +#define I2C_FUNC_SMBUS_HOST_NOTIFY 0x10000000 > > #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \ > I2C_FUNC_SMBUS_WRITE_BYTE)
Hi Jean, On Jun 29 2015 or thereabouts, Jean Delvare wrote: > Hi Benjamin, > > On Tue, 23 Jun 2015 14:58:18 -0400, Benjamin Tissoires wrote: > > SMBus Host Notify allows a slave device to act as a master on a bus to > > notify the host of an interrupt. The functionality is directly implemented > > in the firmware so we just export a toggle function and rely on the > > adapter to actually support this. > > Why does it need to be toggled? I mean, if the controller supports it, > why don't we just enable the feature all the time? That is definitively a solution. I however had once a problem with suspend/resume where i2c_i801 was not able to reset the Host Notify feature, but that was maybe a side effect of unloading/reloading the module tons of times during the session. I will work on that and submit a v2 this week. I still wonder if you think we should expose a KConfig parameter for this or not. I would prefer not to (because it is handled in hardware and people might screw up their input drivers), but I'd prefer have your opinion on this first. > > > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> > > --- > > Documentation/i2c/smbus-protocol | 4 ++++ > > drivers/i2c/i2c-core.c | 26 ++++++++++++++++++++++++++ > > include/linux/i2c.h | 8 ++++++++ > > include/uapi/linux/i2c.h | 1 + > > 4 files changed, 39 insertions(+) > > > > diff --git a/Documentation/i2c/smbus-protocol b/Documentation/i2c/smbus-protocol > > index 6012b12..af4e4b9 100644 > > --- a/Documentation/i2c/smbus-protocol > > +++ b/Documentation/i2c/smbus-protocol > > @@ -199,6 +199,10 @@ alerting device's address. > > > > [S] [HostAddr] [Wr] A [DevAddr] A [DataLow] A [DataHigh] A [P] > > > > +I2C drivers for devices which can trigger SMBus Host Notify should call > > +i2c_smbus_toggle_host_notify() to enable SMBUS Host Notify on the adapter > > +and implement the optional alert() callback. > > + > > > > Packet Error Checking (PEC) > > =========================== > > diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c > > index 987c124..eaaf5b0 100644 > > --- a/drivers/i2c/i2c-core.c > > +++ b/drivers/i2c/i2c-core.c > > @@ -2959,6 +2959,32 @@ int i2c_slave_unregister(struct i2c_client *client) > > EXPORT_SYMBOL_GPL(i2c_slave_unregister); > > #endif > > > > +int i2c_smbus_toggle_host_notify(struct i2c_client *client, bool state) > > +{ > > + int ret; > > + > > + if (!client) > > + return -EINVAL; > > + > > + if (!(client->flags & I2C_CLIENT_TEN)) { > > + /* Enforce stricter address checking */ > > + ret = i2c_check_addr_validity(client->addr); > > + if (ret) > > + return ret; > > + } > > + > > + if (!client->adapter->algo->toggle_smbus_host_notify) > > + return -EOPNOTSUPP; > > + > > + i2c_lock_adapter(client->adapter); > > + ret = client->adapter->algo->toggle_smbus_host_notify(client->adapter, > > + state); > > + i2c_unlock_adapter(client->adapter); > > + > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(i2c_smbus_toggle_host_notify); > > + > > As this is an SMBus feature, can't it go to drivers/i2c/i2c-smbus.c? I asked myself this question, and I figured it was not possible because i2c-smbus consists in the smbus_alert i2c driver. After re-reading the code, I see now that it could definitively goes there too. However, if we choose not to expose the toggle to the drivers, then there will be no need to make deep changes in i2c-smbus :). > > > MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); > > MODULE_DESCRIPTION("I2C-Bus main module"); > > MODULE_LICENSE("GPL"); > > diff --git a/include/linux/i2c.h b/include/linux/i2c.h > > index e83a738..7ffc970 100644 > > --- a/include/linux/i2c.h > > +++ b/include/linux/i2c.h > > @@ -177,6 +177,8 @@ struct i2c_driver { > > * The format and meaning of the data value depends on the protocol. > > * For the SMBus alert protocol, there is a single bit of data passed > > * as the alert response's low bit ("event flag"). > > + * For the SMBus Host Notify protocol, the data corresponds to the > > + * 16-bits payload data reported by the external device. > > 16-bit (no s) ack > > > */ > > void (*alert)(struct i2c_client *, unsigned int data); > > > > @@ -270,6 +272,9 @@ static inline int i2c_slave_event(struct i2c_client *client, > > } > > #endif > > > > + > > No double blank lines in source code please. oops, sorry. > > > +extern int i2c_smbus_toggle_host_notify(struct i2c_client *client, bool state); > > + > > /** > > * struct i2c_board_info - template for device creation > > * @type: chip type, to initialize i2c_client.name > > @@ -378,6 +383,8 @@ i2c_register_board_info(int busnum, struct i2c_board_info const *info, > > * from the I2C_FUNC_* flags. > > * @reg_slave: Register given client to I2C slave mode of this adapter > > * @unreg_slave: Unregister given client from I2C slave mode of this adapter > > + * @toggle_smbus_host_notify: toggle the SMBus Host Notify support of this > > + * adapter. > > * > > * The following structs are for those who like to implement new bus drivers: > > * i2c_algorithm is the interface to a class of hardware solutions which can > > @@ -408,6 +415,7 @@ struct i2c_algorithm { > > int (*reg_slave)(struct i2c_client *client); > > int (*unreg_slave)(struct i2c_client *client); > > #endif > > + int (*toggle_smbus_host_notify)(struct i2c_adapter *adap, bool state); > > Please put it after u32 (*functionality), so that the field offsets do > not depend on configuration options. OK. But again, if we enable it anyway, this will be just removed. > > > }; > > > > /** > > diff --git a/include/uapi/linux/i2c.h b/include/uapi/linux/i2c.h > > index 0e949cb..c72708e 100644 > > --- a/include/uapi/linux/i2c.h > > +++ b/include/uapi/linux/i2c.h > > @@ -100,6 +100,7 @@ struct i2c_msg { > > #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000 > > #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */ > > #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */ > > +#define I2C_FUNC_SMBUS_HOST_NOTIFY 0x10000000 > > > > #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \ > > I2C_FUNC_SMBUS_WRITE_BYTE) > Thanks for the review! Cheers, Benjamin -- 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
On Tue, 7 Jul 2015 10:23:33 -0400, Benjamin Tissoires wrote: > Hi Jean, > > On Jun 29 2015 or thereabouts, Jean Delvare wrote: > > Hi Benjamin, > > > > On Tue, 23 Jun 2015 14:58:18 -0400, Benjamin Tissoires wrote: > > > SMBus Host Notify allows a slave device to act as a master on a bus to > > > notify the host of an interrupt. The functionality is directly implemented > > > in the firmware so we just export a toggle function and rely on the > > > adapter to actually support this. > > > > Why does it need to be toggled? I mean, if the controller supports it, > > why don't we just enable the feature all the time? > > That is definitively a solution. I however had once a problem with > suspend/resume where i2c_i801 was not able to reset the Host Notify > feature, but that was maybe a side effect of unloading/reloading the > module tons of times during the session. > > I will work on that and submit a v2 this week. > > I still wonder if you think we should expose a KConfig parameter for > this or not. I would prefer not to (because it is handled in hardware > and people might screw up their input drivers), but I'd prefer have your > opinion on this first. What would the Kconfig option do exactly? As a general rule, the fewer Kconfig options the better. We already have I2C_SMBUS for the SMBus protocol specifics and Host Notify is one of these. > > > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> > > > --- > > > Documentation/i2c/smbus-protocol | 4 ++++ > > > drivers/i2c/i2c-core.c | 26 ++++++++++++++++++++++++++ > > > include/linux/i2c.h | 8 ++++++++ > > > include/uapi/linux/i2c.h | 1 + > > > 4 files changed, 39 insertions(+) > > > > > > diff --git a/Documentation/i2c/smbus-protocol b/Documentation/i2c/smbus-protocol > > > index 6012b12..af4e4b9 100644 > > > --- a/Documentation/i2c/smbus-protocol > > > +++ b/Documentation/i2c/smbus-protocol > > > @@ -199,6 +199,10 @@ alerting device's address. > > > > > > [S] [HostAddr] [Wr] A [DevAddr] A [DataLow] A [DataHigh] A [P] > > > > > > +I2C drivers for devices which can trigger SMBus Host Notify should call > > > +i2c_smbus_toggle_host_notify() to enable SMBUS Host Notify on the adapter > > > +and implement the optional alert() callback. > > > + > > > > > > Packet Error Checking (PEC) > > > =========================== > > > diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c > > > index 987c124..eaaf5b0 100644 > > > --- a/drivers/i2c/i2c-core.c > > > +++ b/drivers/i2c/i2c-core.c > > > @@ -2959,6 +2959,32 @@ int i2c_slave_unregister(struct i2c_client *client) > > > EXPORT_SYMBOL_GPL(i2c_slave_unregister); > > > #endif > > > > > > +int i2c_smbus_toggle_host_notify(struct i2c_client *client, bool state) > > > +{ > > > + int ret; > > > + > > > + if (!client) > > > + return -EINVAL; > > > + > > > + if (!(client->flags & I2C_CLIENT_TEN)) { > > > + /* Enforce stricter address checking */ > > > + ret = i2c_check_addr_validity(client->addr); > > > + if (ret) > > > + return ret; > > > + } > > > + > > > + if (!client->adapter->algo->toggle_smbus_host_notify) > > > + return -EOPNOTSUPP; > > > + > > > + i2c_lock_adapter(client->adapter); > > > + ret = client->adapter->algo->toggle_smbus_host_notify(client->adapter, > > > + state); > > > + i2c_unlock_adapter(client->adapter); > > > + > > > + return ret; > > > +} > > > +EXPORT_SYMBOL_GPL(i2c_smbus_toggle_host_notify); > > > + > > > > As this is an SMBus feature, can't it go to drivers/i2c/i2c-smbus.c? > > I asked myself this question, and I figured it was not possible because > i2c-smbus consists in the smbus_alert i2c driver. > > After re-reading the code, I see now that it could definitively goes > there too. However, if we choose not to expose the toggle to the > drivers, then there will be no need to make deep changes in i2c-smbus > :). The smbus_alert i2c driver was just the most simple way to implement the SMBus Alert feature. It's not an actual device driver, nothing to be afraid of. > (...) > Thanks for the review! You're welcome. I wish I could do more but -ENOTIME :/
On Jul 07 2015 or thereabouts, Jean Delvare wrote: > On Tue, 7 Jul 2015 10:23:33 -0400, Benjamin Tissoires wrote: > > Hi Jean, > > > > On Jun 29 2015 or thereabouts, Jean Delvare wrote: > > > Hi Benjamin, > > > > > > On Tue, 23 Jun 2015 14:58:18 -0400, Benjamin Tissoires wrote: > > > > SMBus Host Notify allows a slave device to act as a master on a bus to > > > > notify the host of an interrupt. The functionality is directly implemented > > > > in the firmware so we just export a toggle function and rely on the > > > > adapter to actually support this. > > > > > > Why does it need to be toggled? I mean, if the controller supports it, > > > why don't we just enable the feature all the time? > > > > That is definitively a solution. I however had once a problem with > > suspend/resume where i2c_i801 was not able to reset the Host Notify > > feature, but that was maybe a side effect of unloading/reloading the > > module tons of times during the session. > > > > I will work on that and submit a v2 this week. > > > > I still wonder if you think we should expose a KConfig parameter for > > this or not. I would prefer not to (because it is handled in hardware > > and people might screw up their input drivers), but I'd prefer have your > > opinion on this first. > > What would the Kconfig option do exactly? As a general rule, the fewer > Kconfig options the better. We already have I2C_SMBUS for the SMBus > protocol specifics and Host Notify is one of these. Yeah, that was a dumb suggestion. i2c_i801 is a SMBus driver, so we should be able to enable Host Notify unconditionally. > > > > > Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> > > > > --- > > > > Documentation/i2c/smbus-protocol | 4 ++++ > > > > drivers/i2c/i2c-core.c | 26 ++++++++++++++++++++++++++ > > > > include/linux/i2c.h | 8 ++++++++ > > > > include/uapi/linux/i2c.h | 1 + > > > > 4 files changed, 39 insertions(+) > > > > > > > > diff --git a/Documentation/i2c/smbus-protocol b/Documentation/i2c/smbus-protocol > > > > index 6012b12..af4e4b9 100644 > > > > --- a/Documentation/i2c/smbus-protocol > > > > +++ b/Documentation/i2c/smbus-protocol > > > > @@ -199,6 +199,10 @@ alerting device's address. > > > > > > > > [S] [HostAddr] [Wr] A [DevAddr] A [DataLow] A [DataHigh] A [P] > > > > > > > > +I2C drivers for devices which can trigger SMBus Host Notify should call > > > > +i2c_smbus_toggle_host_notify() to enable SMBUS Host Notify on the adapter > > > > +and implement the optional alert() callback. > > > > + > > > > > > > > Packet Error Checking (PEC) > > > > =========================== > > > > diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c > > > > index 987c124..eaaf5b0 100644 > > > > --- a/drivers/i2c/i2c-core.c > > > > +++ b/drivers/i2c/i2c-core.c > > > > @@ -2959,6 +2959,32 @@ int i2c_slave_unregister(struct i2c_client *client) > > > > EXPORT_SYMBOL_GPL(i2c_slave_unregister); > > > > #endif > > > > > > > > +int i2c_smbus_toggle_host_notify(struct i2c_client *client, bool state) > > > > +{ > > > > + int ret; > > > > + > > > > + if (!client) > > > > + return -EINVAL; > > > > + > > > > + if (!(client->flags & I2C_CLIENT_TEN)) { > > > > + /* Enforce stricter address checking */ > > > > + ret = i2c_check_addr_validity(client->addr); > > > > + if (ret) > > > > + return ret; > > > > + } > > > > + > > > > + if (!client->adapter->algo->toggle_smbus_host_notify) > > > > + return -EOPNOTSUPP; > > > > + > > > > + i2c_lock_adapter(client->adapter); > > > > + ret = client->adapter->algo->toggle_smbus_host_notify(client->adapter, > > > > + state); > > > > + i2c_unlock_adapter(client->adapter); > > > > + > > > > + return ret; > > > > +} > > > > +EXPORT_SYMBOL_GPL(i2c_smbus_toggle_host_notify); > > > > + > > > > > > As this is an SMBus feature, can't it go to drivers/i2c/i2c-smbus.c? > > > > I asked myself this question, and I figured it was not possible because > > i2c-smbus consists in the smbus_alert i2c driver. > > > > After re-reading the code, I see now that it could definitively goes > > there too. However, if we choose not to expose the toggle to the > > drivers, then there will be no need to make deep changes in i2c-smbus > > :). > > The smbus_alert i2c driver was just the most simple way to implement > the SMBus Alert feature. It's not an actual device driver, nothing to > be afraid of. Hehe. OK. > > > (...) > > Thanks for the review! > > You're welcome. I wish I could do more but -ENOTIME :/ No worries. That's already a lot. And from my side, I was quite silent because I just spent days of vacation without checking mails :) Cheers, Benjamin -- 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
diff --git a/Documentation/i2c/smbus-protocol b/Documentation/i2c/smbus-protocol index 6012b12..af4e4b9 100644 --- a/Documentation/i2c/smbus-protocol +++ b/Documentation/i2c/smbus-protocol @@ -199,6 +199,10 @@ alerting device's address. [S] [HostAddr] [Wr] A [DevAddr] A [DataLow] A [DataHigh] A [P] +I2C drivers for devices which can trigger SMBus Host Notify should call +i2c_smbus_toggle_host_notify() to enable SMBUS Host Notify on the adapter +and implement the optional alert() callback. + Packet Error Checking (PEC) =========================== diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index 987c124..eaaf5b0 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -2959,6 +2959,32 @@ int i2c_slave_unregister(struct i2c_client *client) EXPORT_SYMBOL_GPL(i2c_slave_unregister); #endif +int i2c_smbus_toggle_host_notify(struct i2c_client *client, bool state) +{ + int ret; + + if (!client) + return -EINVAL; + + if (!(client->flags & I2C_CLIENT_TEN)) { + /* Enforce stricter address checking */ + ret = i2c_check_addr_validity(client->addr); + if (ret) + return ret; + } + + if (!client->adapter->algo->toggle_smbus_host_notify) + return -EOPNOTSUPP; + + i2c_lock_adapter(client->adapter); + ret = client->adapter->algo->toggle_smbus_host_notify(client->adapter, + state); + i2c_unlock_adapter(client->adapter); + + return ret; +} +EXPORT_SYMBOL_GPL(i2c_smbus_toggle_host_notify); + MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); MODULE_DESCRIPTION("I2C-Bus main module"); MODULE_LICENSE("GPL"); diff --git a/include/linux/i2c.h b/include/linux/i2c.h index e83a738..7ffc970 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -177,6 +177,8 @@ struct i2c_driver { * The format and meaning of the data value depends on the protocol. * For the SMBus alert protocol, there is a single bit of data passed * as the alert response's low bit ("event flag"). + * For the SMBus Host Notify protocol, the data corresponds to the + * 16-bits payload data reported by the external device. */ void (*alert)(struct i2c_client *, unsigned int data); @@ -270,6 +272,9 @@ static inline int i2c_slave_event(struct i2c_client *client, } #endif + +extern int i2c_smbus_toggle_host_notify(struct i2c_client *client, bool state); + /** * struct i2c_board_info - template for device creation * @type: chip type, to initialize i2c_client.name @@ -378,6 +383,8 @@ i2c_register_board_info(int busnum, struct i2c_board_info const *info, * from the I2C_FUNC_* flags. * @reg_slave: Register given client to I2C slave mode of this adapter * @unreg_slave: Unregister given client from I2C slave mode of this adapter + * @toggle_smbus_host_notify: toggle the SMBus Host Notify support of this + * adapter. * * The following structs are for those who like to implement new bus drivers: * i2c_algorithm is the interface to a class of hardware solutions which can @@ -408,6 +415,7 @@ struct i2c_algorithm { int (*reg_slave)(struct i2c_client *client); int (*unreg_slave)(struct i2c_client *client); #endif + int (*toggle_smbus_host_notify)(struct i2c_adapter *adap, bool state); }; /** diff --git a/include/uapi/linux/i2c.h b/include/uapi/linux/i2c.h index 0e949cb..c72708e 100644 --- a/include/uapi/linux/i2c.h +++ b/include/uapi/linux/i2c.h @@ -100,6 +100,7 @@ struct i2c_msg { #define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000 #define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* I2C-like block xfer */ #define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* w/ 1-byte reg. addr. */ +#define I2C_FUNC_SMBUS_HOST_NOTIFY 0x10000000 #define I2C_FUNC_SMBUS_BYTE (I2C_FUNC_SMBUS_READ_BYTE | \ I2C_FUNC_SMBUS_WRITE_BYTE)
SMBus Host Notify allows a slave device to act as a master on a bus to notify the host of an interrupt. The functionality is directly implemented in the firmware so we just export a toggle function and rely on the adapter to actually support this. Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> --- Documentation/i2c/smbus-protocol | 4 ++++ drivers/i2c/i2c-core.c | 26 ++++++++++++++++++++++++++ include/linux/i2c.h | 8 ++++++++ include/uapi/linux/i2c.h | 1 + 4 files changed, 39 insertions(+)