Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
On Wed, Oct 24, 2018 at 05:46:22PM +, Ajay Gupta wrote: > Hi Wolfram, > > > I don't think SMBus is an option in this case since the intended > > > client (Cypress something in patch 2/2) does xfers that would need > > > 16-bit commands and I think they are always 8-bit in SMBus, no? > > > > Yes. Command is 8 bit, data can be 16. Thanks for the heads up! > Please help review v13 of this patch set at > https://marc.info/?l=linux-i2c=153859126630601=2 > https://marc.info/?l=linux-i2c=153859127330604=2 > https://marc.info/?l=linux-i2c=153859127830605=2 It is the middle of the merge window, maintainers are a "bit" busy at the moment :)
RE: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi Wolfram, > > I don't think SMBus is an option in this case since the intended > > client (Cypress something in patch 2/2) does xfers that would need > > 16-bit commands and I think they are always 8-bit in SMBus, no? > > Yes. Command is 8 bit, data can be 16. Thanks for the heads up! Please help review v13 of this patch set at https://marc.info/?l=linux-i2c=153859126630601=2 https://marc.info/?l=linux-i2c=153859127330604=2 https://marc.info/?l=linux-i2c=153859127830605=2 Thanks Ajay --nvpublic
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
> I don't think SMBus is an option in this case since the intended client > (Cypress > something in patch 2/2) does xfers that would need 16-bit commands and I think > they are always 8-bit in SMBus, no? Yes. Command is 8 bit, data can be 16. Thanks for the heads up! signature.asc Description: PGP signature
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
On 2018-10-02 09:27, Wolfram Sang wrote: > Hi, > We got confirmation from HW team about 4 byte read limitation. There has to be a STOP after every single read cycle. One read cycle supports maximum of 4 byte burst. I will update the patches with a comment on this. >>> >>> Could it be that this is more an SMBus controller than an I2C controller? >>> I haven't looked at the specs but maybe populating smbus_xfer instead of >>> master_xfer is an option here? >> I think its more of i2c controller and we do mention " .max_read_len = 4" in >> " struct i2c_adapter_quirks". Do you still see something missing here? > > Well, if there has to be STOP after a read, then you can't do a transfer > containing "write-read-write", or? So, I wondered if this controller is > of the type which can mainly do "write-then-read" transfers only (check > I2C_AQ_COMB* quirk flags). And for some of those controller types, it > might be even easier to drop generic I2C transfers and only handle the > SMBUS calls. > > I didn't check this driver closely yet, so I can't tell if/what it needs > from the above. I wanted to give this input already, though. I don't think SMBus is an option in this case since the intended client (Cypress something in patch 2/2) does xfers that would need 16-bit commands and I think they are always 8-bit in SMBus, no? Cheers, Peter
RE: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi Wolfram,
> > > > We got confirmation from HW team about 4 byte read limitation.
> > > > There has to be a STOP after every single read cycle. One read
> > > > cycle supports maximum of
> > > > 4 byte burst. I will update the patches with a comment on this.
> > >
> > > Could it be that this is more an SMBus controller than an I2C controller?
> > > I haven't looked at the specs but maybe populating smbus_xfer
> > > instead of master_xfer is an option here?
> > I think its more of i2c controller and we do mention " .max_read_len =
> > 4" in " struct i2c_adapter_quirks". Do you still see something missing here?
>
> Well, if there has to be STOP after a read, then you can't do a transfer
> containing "write-read-write", or?
Yes, that's correct.
> So, I wondered if this controller is of the
> type which can mainly do "write-then-read" transfers only (check
> I2C_AQ_COMB* quirk flags).
Yes it is mainly used "write-then-read" and also "write" only.
Read can be maximum of 4 bytes only and write has no size limitation.
I will add the flag I2C_AQ_COMB_WRITE_THEN_READ in the adapter quirk.
static const struct i2c_adapter_quirks gpu_i2c_quirks = {
.max_read_len = 4,
.flags = I2C_AQ_COMB_WRITE_THEN_READ,
};
> And for some of those controller types, it might
> be even easier to drop generic I2C transfers and only handle the SMBUS calls.
>
> I didn't check this driver closely yet, so I can't tell if/what it needs from
> the
> above. I wanted to give this input already, though.
Thanks for early feedback.
Please help review v12 at [1] and provide your input.
Thanks
Ajay
[1]
https://marc.info/?l=linux-usb=153668792309635=2
https://marc.info/?l=linux-usb=153668793009637=2
--nvpublic
>
> Regards,
>
>Wolfram
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi, > > > We got confirmation from HW team about 4 byte read limitation. There > > > has to be a STOP after every single read cycle. One read cycle > > > supports maximum of > > > 4 byte burst. I will update the patches with a comment on this. > > > > Could it be that this is more an SMBus controller than an I2C controller? > > I haven't looked at the specs but maybe populating smbus_xfer instead of > > master_xfer is an option here? > I think its more of i2c controller and we do mention " .max_read_len = 4" in > " struct i2c_adapter_quirks". Do you still see something missing here? Well, if there has to be STOP after a read, then you can't do a transfer containing "write-read-write", or? So, I wondered if this controller is of the type which can mainly do "write-then-read" transfers only (check I2C_AQ_COMB* quirk flags). And for some of those controller types, it might be even easier to drop generic I2C transfers and only handle the SMBUS calls. I didn't check this driver closely yet, so I can't tell if/what it needs from the above. I wanted to give this input already, though. Regards, Wolfram signature.asc Description: PGP signature
RE: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi Wolfram, > > > > > > Can we get the working set in while the issues is being debugged? > > > > > > > > > > I'm not the one making the decision, and I don't even know if > > > > > this is going through the i2c or the usb tree? If it's going > > > > > through the i2c tree you need a tag from the usb people (Greg?) > > > > > on patch 2/2, and if it's going through the usb tree, you need a > > > > > tag from Wolfram on patch 1/2. As I said, I'm not involved with > > > > > that part, I'm just reviewing these patches because I felt like it. > > > > > > > > > > The remaining issue that bothers me is the looping reads, and > > > > > your email address reveals that you should be in a very good > > > > > position to work out why they do not work, and fix it or let us > > > > > know why they don't. > > > I am working with different teams to debug this and I think it may > > > take some time to know the root cause. > > We got confirmation from HW team about 4 byte read limitation. There > > has to be a STOP after every single read cycle. One read cycle > > supports maximum of > > 4 byte burst. I will update the patches with a comment on this. > > Could it be that this is more an SMBus controller than an I2C controller? > I haven't looked at the specs but maybe populating smbus_xfer instead of > master_xfer is an option here? I think its more of i2c controller and we do mention " .max_read_len = 4" in " struct i2c_adapter_quirks". Do you still see something missing here? Thanks Ajay --nvpublic
RE: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi Peter, > I'm not the one making the decision, and I don't even know if this > is going through the i2c or the usb tree? If it's going through the > i2c tree you need a tag from the usb people (Greg?) on patch 2/2, > and if it's going through the usb tree, you need a tag from Wolfram > on patch 1/2. As I said, I'm not involved with that part, I'm just > reviewing these patches because I felt like it. > > The remaining issue that bothers me is the looping reads, and your > email address reveals that you should be in a very good position to > work out why they do not work, and fix it or let us know why they > don't. > >> I am working with different teams to debug this and I think it may > >> take some time to know the root cause. > > We got confirmation from HW team about 4 byte read limitation. There > > has to be a STOP after every single read cycle. One read cycle > > supports maximum of > > 4 byte burst. I will update the patches with a comment on this. > > Thanks for digging into this! And if the HW team says it's not possible, then > of > course my objection falls flat. However, you only mention "read cycle", and > based on your defines (I2C_MST_CNTL_CYCLE_TRIGGER) that seems to be > terminology from the spec. Comment "read cycle" and cycle in define I2C_MST_CNTL_CYCLE_TRIGGER is not related. I should say "There has to be a STOP after every single read". Thanks Ajay --nvpublic > Yet, you apparently do writes without triggering a > cycle. Do the HW team have anything to say about doing reads without > triggering a "cycle"? > > Cheers, > Peter
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
On 2018-10-01 21:33, Ajay Gupta wrote: > Hi Heikki and Peter, > > Can we get the working set in while the issues is being debugged? I'm not the one making the decision, and I don't even know if this is going through the i2c or the usb tree? If it's going through the i2c tree you need a tag from the usb people (Greg?) on patch 2/2, and if it's going through the usb tree, you need a tag from Wolfram on patch 1/2. As I said, I'm not involved with that part, I'm just reviewing these patches because I felt like it. The remaining issue that bothers me is the looping reads, and your email address reveals that you should be in a very good position to work out why they do not work, and fix it or let us know why they don't. >> I am working with different teams to debug this and I think it may take some >> time to know the root cause. > We got confirmation from HW team about 4 byte read limitation. There has to > be a STOP after every single read cycle. One read cycle supports maximum of > 4 byte burst. I will update the patches with a comment on this. Thanks for digging into this! And if the HW team says it's not possible, then of course my objection falls flat. However, you only mention "read cycle", and based on your defines (I2C_MST_CNTL_CYCLE_TRIGGER) that seems to be terminology from the spec. Yet, you apparently do writes without triggering a cycle. Do the HW team have anything to say about doing reads without triggering a "cycle"? Cheers, Peter
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
On Mon, Oct 01, 2018 at 07:33:02PM +, Ajay Gupta wrote: > Hi Heikki and Peter, > > > > > > Can we get the working set in while the issues is being debugged? > > > > > > > > I'm not the one making the decision, and I don't even know if this > > > > is going through the i2c or the usb tree? If it's going through the > > > > i2c tree you need a tag from the usb people (Greg?) on patch 2/2, > > > > and if it's going through the usb tree, you need a tag from Wolfram > > > > on patch 1/2. As I said, I'm not involved with that part, I'm just > > > > reviewing these patches because I felt like it. > > > > > > > > The remaining issue that bothers me is the looping reads, and your > > > > email address reveals that you should be in a very good position to > > > > work out why they do not work, and fix it or let us know why they > > > > don't. > > I am working with different teams to debug this and I think it may take some > > time to know the root cause. > We got confirmation from HW team about 4 byte read limitation. There has to > be a STOP after every single read cycle. One read cycle supports maximum of > 4 byte burst. I will update the patches with a comment on this. Could it be that this is more an SMBus controller than an I2C controller? I haven't looked at the specs but maybe populating smbus_xfer instead of master_xfer is an option here? signature.asc Description: PGP signature
RE: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi Heikki and Peter, > > > > Can we get the working set in while the issues is being debugged? > > > > > > I'm not the one making the decision, and I don't even know if this > > > is going through the i2c or the usb tree? If it's going through the > > > i2c tree you need a tag from the usb people (Greg?) on patch 2/2, > > > and if it's going through the usb tree, you need a tag from Wolfram > > > on patch 1/2. As I said, I'm not involved with that part, I'm just > > > reviewing these patches because I felt like it. > > > > > > The remaining issue that bothers me is the looping reads, and your > > > email address reveals that you should be in a very good position to > > > work out why they do not work, and fix it or let us know why they > > > don't. > I am working with different teams to debug this and I think it may take some > time to know the root cause. We got confirmation from HW team about 4 byte read limitation. There has to be a STOP after every single read cycle. One read cycle supports maximum of 4 byte burst. I will update the patches with a comment on this. Thanks Ajay --nvpublic > > > > --
RE: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi Heikki and Peter, > > > Can we get the working set in while the issues is being debugged? > > > > I'm not the one making the decision, and I don't even know if this is > > going through the i2c or the usb tree? If it's going through the i2c > > tree you need a tag from the usb people (Greg?) on patch 2/2, and if > > it's going through the usb tree, you need a tag from Wolfram on patch > > 1/2. As I said, I'm not involved with that part, I'm just reviewing > > these patches because I felt like it. > > > > The remaining issue that bothers me is the looping reads, and your > > email address reveals that you should be in a very good position to > > work out why they do not work, and fix it or let us know why they > > don't. I am working with different teams to debug this and I think it may take some time to know the root cause. >> However, your responses indicate that you have given up. That > > coupled with the fact that the datasheet is not publicly available > > (but why, seems a little over-protective to think the interface to an > > i2c controller is worth all that much) makes me think that perhaps > > this little detail might never be fixed if it's not fixed now. Once > > merged, there is no pressure on you to actually do anything about it, > > and others are stuck in darkness without a spec. > > I got similar impression. Ajay, you have really made it look like you just > want > to dump the code even though it still has problems, then lift your arms and > never look back. I'm sure that is not the case, but the fact that you are > continuously making pleas, asking us to just accept the code even though it is > not ready, does give that impression. > I can appreciate that you are in a hurry, and I know you have a lot of other > tasks that also need your attention, just like everybody, but I'm asking you > to > take a deep breath, and take one more look at these two drivers. Go over the > code as a whole instead of trying to fix the problems as fast as possible > (you've sent a new version almost daily). > I'm certain you can figure out how to fix that last issue. You are almost > there. > > And when you are ready, please include a cover letter in your next version and > provide some background for these patches if you can. Ok. Thanks Ajay --nvpublic > Ideally you could tell something about the platform that has that the PD > controller and the I2C host. There you can also mention which tree you think > these patches should go through, usb or i2c. I'm guessing usb based on the > fact that the I2C host controller driver seems to be there just for the USB PD > controller, at least for now. > > > Thanks, > > -- > heikki
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi, On Thu, Sep 13, 2018 at 09:36:58AM +0200, Peter Rosin wrote: > On 2018-09-13 00:22, Ajay Gupta wrote: > > Hi Peter, > > Can we get the working set in while the issues is being debugged? > > I'm not the one making the decision, and I don't even know if this > is going through the i2c or the usb tree? If it's going through the > i2c tree you need a tag from the usb people (Greg?) on patch 2/2, > and if it's going through the usb tree, you need a tag from Wolfram > on patch 1/2. As I said, I'm not involved with that part, I'm just > reviewing these patches because I felt like it. > > The remaining issue that bothers me is the looping reads, and your > email address reveals that you should be in a very good position to > work out why they do not work, and fix it or let us know why they > don't. However, your responses indicate that you have given up. That > coupled with the fact that the datasheet is not publicly available > (but why, seems a little over-protective to think the interface to an > i2c controller is worth all that much) makes me think that perhaps > this little detail might never be fixed if it's not fixed now. Once > merged, there is no pressure on you to actually do anything about it, > and others are stuck in darkness without a spec. I got similar impression. Ajay, you have really made it look like you just want to dump the code even though it still has problems, then lift your arms and never look back. I'm sure that is not the case, but the fact that you are continuously making pleas, asking us to just accept the code even though it is not ready, does give that impression. I can appreciate that you are in a hurry, and I know you have a lot of other tasks that also need your attention, just like everybody, but I'm asking you to take a deep breath, and take one more look at these two drivers. Go over the code as a whole instead of trying to fix the problems as fast as possible (you've sent a new version almost daily). I'm certain you can figure out how to fix that last issue. You are almost there. And when you are ready, please include a cover letter in your next version and provide some background for these patches if you can. Ideally you could tell something about the platform that has that the PD controller and the I2C host. There you can also mention which tree you think these patches should go through, usb or i2c. I'm guessing usb based on the fact that the I2C host controller driver seems to be there just for the USB PD controller, at least for now. Thanks, -- heikki
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
On 2018-09-13 00:22, Ajay Gupta wrote: > Hi Peter, > Can we get the working set in while the issues is being debugged? I'm not the one making the decision, and I don't even know if this is going through the i2c or the usb tree? If it's going through the i2c tree you need a tag from the usb people (Greg?) on patch 2/2, and if it's going through the usb tree, you need a tag from Wolfram on patch 1/2. As I said, I'm not involved with that part, I'm just reviewing these patches because I felt like it. The remaining issue that bothers me is the looping reads, and your email address reveals that you should be in a very good position to work out why they do not work, and fix it or let us know why they don't. However, your responses indicate that you have given up. That coupled with the fact that the datasheet is not publicly available (but why, seems a little over-protective to think the interface to an i2c controller is worth all that much) makes me think that perhaps this little detail might never be fixed if it's not fixed now. Once merged, there is no pressure on you to actually do anything about it, and others are stuck in darkness without a spec. > So I assume nothing more left to check on this for now. Have you hooked up a scope to the I2C bus while trying the various attempts to get looping reads working? What makes a difference? Have you talked to the hardware people and described what you have attempted? Maybe they know what is missing? Can the datasheet be made public so that someone with more passion can take a crack at it? Cheers, Peter
RE: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi Peter, > >>> This driver adds I2C bus driver to communicate with Type-C controller. > >>> I2C client driver will be part of USB Type-C UCSI driver. > >>> > >>> Signed-off-by: Ajay Gupta > >>> Reviewed-by: Andy Shevchenko > >>> Reviewed-by: Heikki Krogerus > >>> --- > >>> Changes from v1 -> v2 > >>> None > >>> Changes from v2 -> v3 > >>> Fixed review comments from Andy and Thierry > >>> Rename i2c-gpu.c -> i2c-nvidia-gpu.c Changes from v3 -> v4 > >>> Fixed review comments from Andy > >>> Changes from v4 -> v5 > >>> Fixed review comments from Andy > >>> Changes from v5 -> v6 > >>> None > >>> Changes from v6 -> v7 -> v8 > >>> Fixed review comments from Peter > >>> - Add implicit STOP for last write message > >>> - Add i2c_adapter_quirks with max_read_len and > >>> I2C_AQ_COMB flags > >>> Changes from v8 -> v9 > >>> Fixed review comments from Peter > >>> - Drop do_start flag > >>> - Use i2c_8bit_addr_from_msg() > >>> Changes from v9 -> v10 > >>> Fixed review comments from Peter > >>> - Dropped I2C_FUNC_SMBUS_EMUL > >>> - Dropped local mutex > >>> Changes from v10 -> v11 > >>> Fixed review comments from Peter > >>> - Moved stop in master_xfer at end of message > >>> - Change i2c_read without STOP > >>> - Dropped I2C_AC_COMB* flags > >>> Changes from v11 -> v12 > >>> Fixed review comments from Peter > >>> - Removed clearing of empty bits > >>> - Fix master_xfer for correct stop use > >>> > >>> Documentation/i2c/busses/i2c-nvidia-gpu | 18 ++ > >>> MAINTAINERS | 7 + > >>> drivers/i2c/busses/Kconfig | 9 + > >>> drivers/i2c/busses/Makefile | 1 + > >>> drivers/i2c/busses/i2c-nvidia-gpu.c | 368 > >> > >>> 5 files changed, 403 insertions(+) > >>> create mode 100644 Documentation/i2c/busses/i2c-nvidia-gpu > >>> create mode 100644 drivers/i2c/busses/i2c-nvidia-gpu.c > >>> > >>> diff --git a/Documentation/i2c/busses/i2c-nvidia-gpu > >>> b/Documentation/i2c/busses/i2c-nvidia-gpu > >>> new file mode 100644 > >>> index 000..31884d2 > >>> --- /dev/null > >>> +++ b/Documentation/i2c/busses/i2c-nvidia-gpu > >>> @@ -0,0 +1,18 @@ > >>> +Kernel driver i2c-nvidia-gpu > >>> + > >>> +Datasheet: not publicly available. > >>> + > >>> +Authors: > >>> + Ajay Gupta > >>> + > >>> +Description > >>> +--- > >>> + > >>> +i2c-nvidia-gpu is a driver for I2C controller included in NVIDIA > >>> +Turing and later GPUs and it is used to communicate with Type-C > >>> +controller > >> on GPUs. > >>> + > >>> +If your 'lspci -v' listing shows something like the following, > >>> + > >>> +01:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device > >>> +1ad9 (rev a1) > >>> + > >>> +then this driver should support the I2C controller of your GPU. > >>> diff --git a/MAINTAINERS b/MAINTAINERS index d870cb5..b71b0b4 > 100644 > >>> --- a/MAINTAINERS > >>> +++ b/MAINTAINERS > >>> @@ -6798,6 +6798,13 @@ L: linux-a...@vger.kernel.org > >>> S: Maintained > >>> F: drivers/i2c/i2c-core-acpi.c > >>> > >>> +I2C CONTROLLER DRIVER FOR NVIDIA GPU > >>> +M: Ajay Gupta > >>> +L: linux-...@vger.kernel.org > >>> +S: Maintained > >>> +F: Documentation/i2c/busses/i2c-nvidia-gpu > >>> +F: drivers/i2c/busses/i2c-nvidia-gpu.c > >>> + > >>> I2C MUXES > >>> M: Peter Rosin > >>> L: linux-...@vger.kernel.org > >>> diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > >>> index 451d4ae..eed827b 100644 > >>> --- a/drivers/i2c/busses/Kconfig > >>> +++ b/drivers/i2c/busses/Kconfig > >>> @@ -224,6 +224,15 @@ config I2C_NFORCE2_S4985 > >>> This driver can also be built as a module. If so, the module > >>> will be called i2c-nforce2-s4985. > >>> > >>> +config I2C_NVIDIA_GPU > >>> + tristate "NVIDIA GPU I2C controller" > >>> + depends on PCI > >>> + help > >>> + If you say yes to this option, support will be included for the > >>> + NVIDIA GPU I2C controller which is used to communicate with the > >> GPU's > >>> + Type-C controller. This driver can also be built as a module called > >>> + i2c-nvidia-gpu. > >>> + > >>> config I2C_SIS5595 > >>> tristate "SiS 5595" > >>> depends on PCI > >>> diff --git a/drivers/i2c/busses/Makefile > >>> b/drivers/i2c/busses/Makefile index 18b26af..d499813 100644 > >>> --- a/drivers/i2c/busses/Makefile > >>> +++ b/drivers/i2c/busses/Makefile > >>> @@ -140,5 +140,6 @@ obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o > >>> obj-$(CONFIG_I2C_XGENE_SLIMPRO) += i2c-xgene-slimpro.o > >>> obj-$(CONFIG_SCx200_ACB) += scx200_acb.o > >>> obj-$(CONFIG_I2C_FSI)+= i2c-fsi.o > >>> +obj-$(CONFIG_I2C_NVIDIA_GPU) += i2c-nvidia-gpu.o > >>> > >>> ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG diff --git > >>> a/drivers/i2c/busses/i2c-nvidia-gpu.c > >>> b/drivers/i2c/busses/i2c-nvidia-gpu.c > >>> new file mode 100644 > >>> index 000..0c16b0a > >>> --- /dev/null > >>> +++
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
On 2018-09-12 20:02, Ajay Gupta wrote: > Hi Peter, > >>> This driver adds I2C bus driver to communicate with Type-C controller. >>> I2C client driver will be part of USB Type-C UCSI driver. >>> >>> Signed-off-by: Ajay Gupta >>> Reviewed-by: Andy Shevchenko >>> Reviewed-by: Heikki Krogerus >>> --- >>> Changes from v1 -> v2 >>> None >>> Changes from v2 -> v3 >>> Fixed review comments from Andy and Thierry >>> Rename i2c-gpu.c -> i2c-nvidia-gpu.c >>> Changes from v3 -> v4 >>> Fixed review comments from Andy >>> Changes from v4 -> v5 >>> Fixed review comments from Andy >>> Changes from v5 -> v6 >>> None >>> Changes from v6 -> v7 -> v8 >>> Fixed review comments from Peter >>> - Add implicit STOP for last write message >>> - Add i2c_adapter_quirks with max_read_len and >>> I2C_AQ_COMB flags >>> Changes from v8 -> v9 >>> Fixed review comments from Peter >>> - Drop do_start flag >>> - Use i2c_8bit_addr_from_msg() >>> Changes from v9 -> v10 >>> Fixed review comments from Peter >>> - Dropped I2C_FUNC_SMBUS_EMUL >>> - Dropped local mutex >>> Changes from v10 -> v11 >>> Fixed review comments from Peter >>> - Moved stop in master_xfer at end of message >>> - Change i2c_read without STOP >>> - Dropped I2C_AC_COMB* flags >>> Changes from v11 -> v12 >>> Fixed review comments from Peter >>> - Removed clearing of empty bits >>> - Fix master_xfer for correct stop use >>> >>> Documentation/i2c/busses/i2c-nvidia-gpu | 18 ++ >>> MAINTAINERS | 7 + >>> drivers/i2c/busses/Kconfig | 9 + >>> drivers/i2c/busses/Makefile | 1 + >>> drivers/i2c/busses/i2c-nvidia-gpu.c | 368 >> >>> 5 files changed, 403 insertions(+) >>> create mode 100644 Documentation/i2c/busses/i2c-nvidia-gpu >>> create mode 100644 drivers/i2c/busses/i2c-nvidia-gpu.c >>> >>> diff --git a/Documentation/i2c/busses/i2c-nvidia-gpu >>> b/Documentation/i2c/busses/i2c-nvidia-gpu >>> new file mode 100644 >>> index 000..31884d2 >>> --- /dev/null >>> +++ b/Documentation/i2c/busses/i2c-nvidia-gpu >>> @@ -0,0 +1,18 @@ >>> +Kernel driver i2c-nvidia-gpu >>> + >>> +Datasheet: not publicly available. >>> + >>> +Authors: >>> + Ajay Gupta >>> + >>> +Description >>> +--- >>> + >>> +i2c-nvidia-gpu is a driver for I2C controller included in NVIDIA >>> +Turing and later GPUs and it is used to communicate with Type-C controller >> on GPUs. >>> + >>> +If your 'lspci -v' listing shows something like the following, >>> + >>> +01:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device 1ad9 >>> +(rev a1) >>> + >>> +then this driver should support the I2C controller of your GPU. >>> diff --git a/MAINTAINERS b/MAINTAINERS index d870cb5..b71b0b4 100644 >>> --- a/MAINTAINERS >>> +++ b/MAINTAINERS >>> @@ -6798,6 +6798,13 @@ L: linux-a...@vger.kernel.org >>> S: Maintained >>> F: drivers/i2c/i2c-core-acpi.c >>> >>> +I2C CONTROLLER DRIVER FOR NVIDIA GPU >>> +M: Ajay Gupta >>> +L: linux-...@vger.kernel.org >>> +S: Maintained >>> +F: Documentation/i2c/busses/i2c-nvidia-gpu >>> +F: drivers/i2c/busses/i2c-nvidia-gpu.c >>> + >>> I2C MUXES >>> M: Peter Rosin >>> L: linux-...@vger.kernel.org >>> diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig >>> index 451d4ae..eed827b 100644 >>> --- a/drivers/i2c/busses/Kconfig >>> +++ b/drivers/i2c/busses/Kconfig >>> @@ -224,6 +224,15 @@ config I2C_NFORCE2_S4985 >>> This driver can also be built as a module. If so, the module >>> will be called i2c-nforce2-s4985. >>> >>> +config I2C_NVIDIA_GPU >>> + tristate "NVIDIA GPU I2C controller" >>> + depends on PCI >>> + help >>> + If you say yes to this option, support will be included for the >>> + NVIDIA GPU I2C controller which is used to communicate with the >> GPU's >>> + Type-C controller. This driver can also be built as a module called >>> + i2c-nvidia-gpu. >>> + >>> config I2C_SIS5595 >>> tristate "SiS 5595" >>> depends on PCI >>> diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile >>> index 18b26af..d499813 100644 >>> --- a/drivers/i2c/busses/Makefile >>> +++ b/drivers/i2c/busses/Makefile >>> @@ -140,5 +140,6 @@ obj-$(CONFIG_I2C_SIBYTE)+= i2c-sibyte.o >>> obj-$(CONFIG_I2C_XGENE_SLIMPRO) += i2c-xgene-slimpro.o >>> obj-$(CONFIG_SCx200_ACB) += scx200_acb.o >>> obj-$(CONFIG_I2C_FSI) += i2c-fsi.o >>> +obj-$(CONFIG_I2C_NVIDIA_GPU) += i2c-nvidia-gpu.o >>> >>> ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG diff --git >>> a/drivers/i2c/busses/i2c-nvidia-gpu.c >>> b/drivers/i2c/busses/i2c-nvidia-gpu.c >>> new file mode 100644 >>> index 000..0c16b0a >>> --- /dev/null >>> +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c >>> @@ -0,0 +1,368 @@ >>> +// SPDX-License-Identifier: GPL-2.0 >>> +/* >>> + * Nvidia GPU I2C controller Driver >>> + * >>> + * Copyright (C) 2018 NVIDIA Corporation. All rights
RE: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi Peter, > > This driver adds I2C bus driver to communicate with Type-C controller. > > I2C client driver will be part of USB Type-C UCSI driver. > > > > Signed-off-by: Ajay Gupta > > Reviewed-by: Andy Shevchenko > > Reviewed-by: Heikki Krogerus > > --- > > Changes from v1 -> v2 > > None > > Changes from v2 -> v3 > > Fixed review comments from Andy and Thierry > > Rename i2c-gpu.c -> i2c-nvidia-gpu.c > > Changes from v3 -> v4 > > Fixed review comments from Andy > > Changes from v4 -> v5 > > Fixed review comments from Andy > > Changes from v5 -> v6 > > None > > Changes from v6 -> v7 -> v8 > > Fixed review comments from Peter > > - Add implicit STOP for last write message > > - Add i2c_adapter_quirks with max_read_len and > > I2C_AQ_COMB flags > > Changes from v8 -> v9 > > Fixed review comments from Peter > > - Drop do_start flag > > - Use i2c_8bit_addr_from_msg() > > Changes from v9 -> v10 > > Fixed review comments from Peter > > - Dropped I2C_FUNC_SMBUS_EMUL > > - Dropped local mutex > > Changes from v10 -> v11 > > Fixed review comments from Peter > > - Moved stop in master_xfer at end of message > > - Change i2c_read without STOP > > - Dropped I2C_AC_COMB* flags > > Changes from v11 -> v12 > > Fixed review comments from Peter > > - Removed clearing of empty bits > > - Fix master_xfer for correct stop use > > > > Documentation/i2c/busses/i2c-nvidia-gpu | 18 ++ > > MAINTAINERS | 7 + > > drivers/i2c/busses/Kconfig | 9 + > > drivers/i2c/busses/Makefile | 1 + > > drivers/i2c/busses/i2c-nvidia-gpu.c | 368 > > > 5 files changed, 403 insertions(+) > > create mode 100644 Documentation/i2c/busses/i2c-nvidia-gpu > > create mode 100644 drivers/i2c/busses/i2c-nvidia-gpu.c > > > > diff --git a/Documentation/i2c/busses/i2c-nvidia-gpu > > b/Documentation/i2c/busses/i2c-nvidia-gpu > > new file mode 100644 > > index 000..31884d2 > > --- /dev/null > > +++ b/Documentation/i2c/busses/i2c-nvidia-gpu > > @@ -0,0 +1,18 @@ > > +Kernel driver i2c-nvidia-gpu > > + > > +Datasheet: not publicly available. > > + > > +Authors: > > + Ajay Gupta > > + > > +Description > > +--- > > + > > +i2c-nvidia-gpu is a driver for I2C controller included in NVIDIA > > +Turing and later GPUs and it is used to communicate with Type-C controller > on GPUs. > > + > > +If your 'lspci -v' listing shows something like the following, > > + > > +01:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device 1ad9 > > +(rev a1) > > + > > +then this driver should support the I2C controller of your GPU. > > diff --git a/MAINTAINERS b/MAINTAINERS index d870cb5..b71b0b4 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -6798,6 +6798,13 @@ L: linux-a...@vger.kernel.org > > S: Maintained > > F: drivers/i2c/i2c-core-acpi.c > > > > +I2C CONTROLLER DRIVER FOR NVIDIA GPU > > +M: Ajay Gupta > > +L: linux-...@vger.kernel.org > > +S: Maintained > > +F: Documentation/i2c/busses/i2c-nvidia-gpu > > +F: drivers/i2c/busses/i2c-nvidia-gpu.c > > + > > I2C MUXES > > M: Peter Rosin > > L: linux-...@vger.kernel.org > > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > > index 451d4ae..eed827b 100644 > > --- a/drivers/i2c/busses/Kconfig > > +++ b/drivers/i2c/busses/Kconfig > > @@ -224,6 +224,15 @@ config I2C_NFORCE2_S4985 > > This driver can also be built as a module. If so, the module > > will be called i2c-nforce2-s4985. > > > > +config I2C_NVIDIA_GPU > > + tristate "NVIDIA GPU I2C controller" > > + depends on PCI > > + help > > + If you say yes to this option, support will be included for the > > + NVIDIA GPU I2C controller which is used to communicate with the > GPU's > > + Type-C controller. This driver can also be built as a module called > > + i2c-nvidia-gpu. > > + > > config I2C_SIS5595 > > tristate "SiS 5595" > > depends on PCI > > diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile > > index 18b26af..d499813 100644 > > --- a/drivers/i2c/busses/Makefile > > +++ b/drivers/i2c/busses/Makefile > > @@ -140,5 +140,6 @@ obj-$(CONFIG_I2C_SIBYTE)+= i2c-sibyte.o > > obj-$(CONFIG_I2C_XGENE_SLIMPRO) += i2c-xgene-slimpro.o > > obj-$(CONFIG_SCx200_ACB) += scx200_acb.o > > obj-$(CONFIG_I2C_FSI) += i2c-fsi.o > > +obj-$(CONFIG_I2C_NVIDIA_GPU) += i2c-nvidia-gpu.o > > > > ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG diff --git > > a/drivers/i2c/busses/i2c-nvidia-gpu.c > > b/drivers/i2c/busses/i2c-nvidia-gpu.c > > new file mode 100644 > > index 000..0c16b0a > > --- /dev/null > > +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c > > @@ -0,0 +1,368 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Nvidia GPU I2C controller Driver > > + * > > + * Copyright (C) 2018 NVIDIA Corporation. All rights reserved. > > + * Author: Ajay Gupta */ #include
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
On 2018-09-11 19:45, Ajay Gupta wrote: > Latest NVIDIA GPU card has USB Type-C interface. There is a > Type-C controller which can be accessed over I2C. > > This driver adds I2C bus driver to communicate with Type-C controller. > I2C client driver will be part of USB Type-C UCSI driver. > > Signed-off-by: Ajay Gupta > Reviewed-by: Andy Shevchenko > Reviewed-by: Heikki Krogerus > --- > Changes from v1 -> v2 > None > Changes from v2 -> v3 > Fixed review comments from Andy and Thierry > Rename i2c-gpu.c -> i2c-nvidia-gpu.c > Changes from v3 -> v4 > Fixed review comments from Andy > Changes from v4 -> v5 > Fixed review comments from Andy > Changes from v5 -> v6 > None > Changes from v6 -> v7 -> v8 > Fixed review comments from Peter > - Add implicit STOP for last write message > - Add i2c_adapter_quirks with max_read_len and > I2C_AQ_COMB flags > Changes from v8 -> v9 > Fixed review comments from Peter > - Drop do_start flag > - Use i2c_8bit_addr_from_msg() > Changes from v9 -> v10 > Fixed review comments from Peter > - Dropped I2C_FUNC_SMBUS_EMUL > - Dropped local mutex > Changes from v10 -> v11 > Fixed review comments from Peter > - Moved stop in master_xfer at end of message > - Change i2c_read without STOP > - Dropped I2C_AC_COMB* flags > Changes from v11 -> v12 > Fixed review comments from Peter > - Removed clearing of empty bits > - Fix master_xfer for correct stop use > > Documentation/i2c/busses/i2c-nvidia-gpu | 18 ++ > MAINTAINERS | 7 + > drivers/i2c/busses/Kconfig | 9 + > drivers/i2c/busses/Makefile | 1 + > drivers/i2c/busses/i2c-nvidia-gpu.c | 368 > > 5 files changed, 403 insertions(+) > create mode 100644 Documentation/i2c/busses/i2c-nvidia-gpu > create mode 100644 drivers/i2c/busses/i2c-nvidia-gpu.c > > diff --git a/Documentation/i2c/busses/i2c-nvidia-gpu > b/Documentation/i2c/busses/i2c-nvidia-gpu > new file mode 100644 > index 000..31884d2 > --- /dev/null > +++ b/Documentation/i2c/busses/i2c-nvidia-gpu > @@ -0,0 +1,18 @@ > +Kernel driver i2c-nvidia-gpu > + > +Datasheet: not publicly available. > + > +Authors: > + Ajay Gupta > + > +Description > +--- > + > +i2c-nvidia-gpu is a driver for I2C controller included in NVIDIA Turing > +and later GPUs and it is used to communicate with Type-C controller on GPUs. > + > +If your 'lspci -v' listing shows something like the following, > + > +01:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device 1ad9 (rev a1) > + > +then this driver should support the I2C controller of your GPU. > diff --git a/MAINTAINERS b/MAINTAINERS > index d870cb5..b71b0b4 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -6798,6 +6798,13 @@ L: linux-a...@vger.kernel.org > S: Maintained > F: drivers/i2c/i2c-core-acpi.c > > +I2C CONTROLLER DRIVER FOR NVIDIA GPU > +M: Ajay Gupta > +L: linux-...@vger.kernel.org > +S: Maintained > +F: Documentation/i2c/busses/i2c-nvidia-gpu > +F: drivers/i2c/busses/i2c-nvidia-gpu.c > + > I2C MUXES > M: Peter Rosin > L: linux-...@vger.kernel.org > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > index 451d4ae..eed827b 100644 > --- a/drivers/i2c/busses/Kconfig > +++ b/drivers/i2c/busses/Kconfig > @@ -224,6 +224,15 @@ config I2C_NFORCE2_S4985 > This driver can also be built as a module. If so, the module > will be called i2c-nforce2-s4985. > > +config I2C_NVIDIA_GPU > + tristate "NVIDIA GPU I2C controller" > + depends on PCI > + help > + If you say yes to this option, support will be included for the > + NVIDIA GPU I2C controller which is used to communicate with the GPU's > + Type-C controller. This driver can also be built as a module called > + i2c-nvidia-gpu. > + > config I2C_SIS5595 > tristate "SiS 5595" > depends on PCI > diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile > index 18b26af..d499813 100644 > --- a/drivers/i2c/busses/Makefile > +++ b/drivers/i2c/busses/Makefile > @@ -140,5 +140,6 @@ obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o > obj-$(CONFIG_I2C_XGENE_SLIMPRO) += i2c-xgene-slimpro.o > obj-$(CONFIG_SCx200_ACB) += scx200_acb.o > obj-$(CONFIG_I2C_FSI)+= i2c-fsi.o > +obj-$(CONFIG_I2C_NVIDIA_GPU) += i2c-nvidia-gpu.o > > ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG > diff --git a/drivers/i2c/busses/i2c-nvidia-gpu.c > b/drivers/i2c/busses/i2c-nvidia-gpu.c > new file mode 100644 > index 000..0c16b0a > --- /dev/null > +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c > @@ -0,0 +1,368 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Nvidia GPU I2C controller Driver > + * > + * Copyright (C) 2018 NVIDIA Corporation. All rights reserved. > + * Author: Ajay Gupta > + */ > +#include > +#include > +#include
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
On 2018-09-12 00:48, Ajay Gupta wrote: >> If it doesn't work, maybe you can tweak something in gpu_i2c_read_byte to >> make it work? > I tried a few tweaks but it didn't work that way. I think it may take time to > get > this part working. > > Can we update this part later when we have it working and let this patch > merged? We could, but it feels like what I suggested should be *very* close. I'll write a new response to v12 1/2 with a new attempt... I've spent so much time looking at this, and this last limitation annoys me. Cheers, Peter
RE: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
Hi Peter, > > Latest NVIDIA GPU card has USB Type-C interface. There is a Type-C > > controller which can be accessed over I2C. > > > > This driver adds I2C bus driver to communicate with Type-C controller. > > I2C client driver will be part of USB Type-C UCSI driver. > > > > Signed-off-by: Ajay Gupta > > Reviewed-by: Andy Shevchenko > > Reviewed-by: Heikki Krogerus > > --- > > Changes from v1 -> v2 > > None > > Changes from v2 -> v3 > > Fixed review comments from Andy and Thierry > > Rename i2c-gpu.c -> i2c-nvidia-gpu.c > > Changes from v3 -> v4 > > Fixed review comments from Andy > > Changes from v4 -> v5 > > Fixed review comments from Andy > > Changes from v5 -> v6 > > None > > Changes from v6 -> v7 -> v8 > > Fixed review comments from Peter > > - Add implicit STOP for last write message > > - Add i2c_adapter_quirks with max_read_len and > > I2C_AQ_COMB flags > > Changes from v8 -> v9 > > Fixed review comments from Peter > > - Drop do_start flag > > - Use i2c_8bit_addr_from_msg() > > Changes from v9 -> v10 > > Fixed review comments from Peter > > - Dropped I2C_FUNC_SMBUS_EMUL > > - Dropped local mutex > > Changes from v10 -> v11 > > Fixed review comments from Peter > > - Moved stop in master_xfer at end of message > > - Change i2c_read without STOP > > - Dropped I2C_AC_COMB* flags > > Changes from v11 -> v12 > > Fixed review comments from Peter > > - Removed clearing of empty bits > > - Fix master_xfer for correct stop use > > > > Documentation/i2c/busses/i2c-nvidia-gpu | 18 ++ > > MAINTAINERS | 7 + > > drivers/i2c/busses/Kconfig | 9 + > > drivers/i2c/busses/Makefile | 1 + > > drivers/i2c/busses/i2c-nvidia-gpu.c | 368 > > > 5 files changed, 403 insertions(+) > > create mode 100644 Documentation/i2c/busses/i2c-nvidia-gpu > > create mode 100644 drivers/i2c/busses/i2c-nvidia-gpu.c > > > > diff --git a/Documentation/i2c/busses/i2c-nvidia-gpu > > b/Documentation/i2c/busses/i2c-nvidia-gpu > > new file mode 100644 > > index 000..31884d2 > > --- /dev/null > > +++ b/Documentation/i2c/busses/i2c-nvidia-gpu > > @@ -0,0 +1,18 @@ > > +Kernel driver i2c-nvidia-gpu > > + > > +Datasheet: not publicly available. > > + > > +Authors: > > + Ajay Gupta > > + > > +Description > > +--- > > + > > +i2c-nvidia-gpu is a driver for I2C controller included in NVIDIA > > +Turing and later GPUs and it is used to communicate with Type-C controller > on GPUs. > > + > > +If your 'lspci -v' listing shows something like the following, > > + > > +01:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device 1ad9 > > +(rev a1) > > + > > +then this driver should support the I2C controller of your GPU. > > diff --git a/MAINTAINERS b/MAINTAINERS index d870cb5..b71b0b4 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -6798,6 +6798,13 @@ L: linux-a...@vger.kernel.org > > S: Maintained > > F: drivers/i2c/i2c-core-acpi.c > > > > +I2C CONTROLLER DRIVER FOR NVIDIA GPU > > +M: Ajay Gupta > > +L: linux-...@vger.kernel.org > > +S: Maintained > > +F: Documentation/i2c/busses/i2c-nvidia-gpu > > +F: drivers/i2c/busses/i2c-nvidia-gpu.c > > + > > I2C MUXES > > M: Peter Rosin > > L: linux-...@vger.kernel.org > > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > > index 451d4ae..eed827b 100644 > > --- a/drivers/i2c/busses/Kconfig > > +++ b/drivers/i2c/busses/Kconfig > > @@ -224,6 +224,15 @@ config I2C_NFORCE2_S4985 > > This driver can also be built as a module. If so, the module > > will be called i2c-nforce2-s4985. > > > > +config I2C_NVIDIA_GPU > > + tristate "NVIDIA GPU I2C controller" > > + depends on PCI > > + help > > + If you say yes to this option, support will be included for the > > + NVIDIA GPU I2C controller which is used to communicate with the > GPU's > > + Type-C controller. This driver can also be built as a module called > > + i2c-nvidia-gpu. > > + > > config I2C_SIS5595 > > tristate "SiS 5595" > > depends on PCI > > diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile > > index 18b26af..d499813 100644 > > --- a/drivers/i2c/busses/Makefile > > +++ b/drivers/i2c/busses/Makefile > > @@ -140,5 +140,6 @@ obj-$(CONFIG_I2C_SIBYTE)+= i2c-sibyte.o > > obj-$(CONFIG_I2C_XGENE_SLIMPRO) += i2c-xgene-slimpro.o > > obj-$(CONFIG_SCx200_ACB) += scx200_acb.o > > obj-$(CONFIG_I2C_FSI) += i2c-fsi.o > > +obj-$(CONFIG_I2C_NVIDIA_GPU) += i2c-nvidia-gpu.o > > > > ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG diff --git > > a/drivers/i2c/busses/i2c-nvidia-gpu.c > > b/drivers/i2c/busses/i2c-nvidia-gpu.c > > new file mode 100644 > > index 000..0c16b0a > > --- /dev/null > > +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c > > @@ -0,0 +1,368 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Nvidia GPU I2C controller
Re: [PATCH v12 1/2] i2c: buses: add i2c bus driver for NVIDIA GPU
On 2018-09-11 19:45, Ajay Gupta wrote: > Latest NVIDIA GPU card has USB Type-C interface. There is a > Type-C controller which can be accessed over I2C. > > This driver adds I2C bus driver to communicate with Type-C controller. > I2C client driver will be part of USB Type-C UCSI driver. > > Signed-off-by: Ajay Gupta > Reviewed-by: Andy Shevchenko > Reviewed-by: Heikki Krogerus > --- > Changes from v1 -> v2 > None > Changes from v2 -> v3 > Fixed review comments from Andy and Thierry > Rename i2c-gpu.c -> i2c-nvidia-gpu.c > Changes from v3 -> v4 > Fixed review comments from Andy > Changes from v4 -> v5 > Fixed review comments from Andy > Changes from v5 -> v6 > None > Changes from v6 -> v7 -> v8 > Fixed review comments from Peter > - Add implicit STOP for last write message > - Add i2c_adapter_quirks with max_read_len and > I2C_AQ_COMB flags > Changes from v8 -> v9 > Fixed review comments from Peter > - Drop do_start flag > - Use i2c_8bit_addr_from_msg() > Changes from v9 -> v10 > Fixed review comments from Peter > - Dropped I2C_FUNC_SMBUS_EMUL > - Dropped local mutex > Changes from v10 -> v11 > Fixed review comments from Peter > - Moved stop in master_xfer at end of message > - Change i2c_read without STOP > - Dropped I2C_AC_COMB* flags > Changes from v11 -> v12 > Fixed review comments from Peter > - Removed clearing of empty bits > - Fix master_xfer for correct stop use > > Documentation/i2c/busses/i2c-nvidia-gpu | 18 ++ > MAINTAINERS | 7 + > drivers/i2c/busses/Kconfig | 9 + > drivers/i2c/busses/Makefile | 1 + > drivers/i2c/busses/i2c-nvidia-gpu.c | 368 > > 5 files changed, 403 insertions(+) > create mode 100644 Documentation/i2c/busses/i2c-nvidia-gpu > create mode 100644 drivers/i2c/busses/i2c-nvidia-gpu.c > > diff --git a/Documentation/i2c/busses/i2c-nvidia-gpu > b/Documentation/i2c/busses/i2c-nvidia-gpu > new file mode 100644 > index 000..31884d2 > --- /dev/null > +++ b/Documentation/i2c/busses/i2c-nvidia-gpu > @@ -0,0 +1,18 @@ > +Kernel driver i2c-nvidia-gpu > + > +Datasheet: not publicly available. > + > +Authors: > + Ajay Gupta > + > +Description > +--- > + > +i2c-nvidia-gpu is a driver for I2C controller included in NVIDIA Turing > +and later GPUs and it is used to communicate with Type-C controller on GPUs. > + > +If your 'lspci -v' listing shows something like the following, > + > +01:00.3 Serial bus controller [0c80]: NVIDIA Corporation Device 1ad9 (rev a1) > + > +then this driver should support the I2C controller of your GPU. > diff --git a/MAINTAINERS b/MAINTAINERS > index d870cb5..b71b0b4 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -6798,6 +6798,13 @@ L: linux-a...@vger.kernel.org > S: Maintained > F: drivers/i2c/i2c-core-acpi.c > > +I2C CONTROLLER DRIVER FOR NVIDIA GPU > +M: Ajay Gupta > +L: linux-...@vger.kernel.org > +S: Maintained > +F: Documentation/i2c/busses/i2c-nvidia-gpu > +F: drivers/i2c/busses/i2c-nvidia-gpu.c > + > I2C MUXES > M: Peter Rosin > L: linux-...@vger.kernel.org > diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig > index 451d4ae..eed827b 100644 > --- a/drivers/i2c/busses/Kconfig > +++ b/drivers/i2c/busses/Kconfig > @@ -224,6 +224,15 @@ config I2C_NFORCE2_S4985 > This driver can also be built as a module. If so, the module > will be called i2c-nforce2-s4985. > > +config I2C_NVIDIA_GPU > + tristate "NVIDIA GPU I2C controller" > + depends on PCI > + help > + If you say yes to this option, support will be included for the > + NVIDIA GPU I2C controller which is used to communicate with the GPU's > + Type-C controller. This driver can also be built as a module called > + i2c-nvidia-gpu. > + > config I2C_SIS5595 > tristate "SiS 5595" > depends on PCI > diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile > index 18b26af..d499813 100644 > --- a/drivers/i2c/busses/Makefile > +++ b/drivers/i2c/busses/Makefile > @@ -140,5 +140,6 @@ obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o > obj-$(CONFIG_I2C_XGENE_SLIMPRO) += i2c-xgene-slimpro.o > obj-$(CONFIG_SCx200_ACB) += scx200_acb.o > obj-$(CONFIG_I2C_FSI)+= i2c-fsi.o > +obj-$(CONFIG_I2C_NVIDIA_GPU) += i2c-nvidia-gpu.o > > ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG > diff --git a/drivers/i2c/busses/i2c-nvidia-gpu.c > b/drivers/i2c/busses/i2c-nvidia-gpu.c > new file mode 100644 > index 000..0c16b0a > --- /dev/null > +++ b/drivers/i2c/busses/i2c-nvidia-gpu.c > @@ -0,0 +1,368 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Nvidia GPU I2C controller Driver > + * > + * Copyright (C) 2018 NVIDIA Corporation. All rights reserved. > + * Author: Ajay Gupta > + */ > +#include > +#include > +#include
