* Re: [PATCH v2 0/9] drm/sun4i: Support multiple display pipelines
From: Maxime Ripard @ 2017-04-24 5:51 UTC (permalink / raw)
To: Chen-Yu Tsai
Cc: David Airlie, Rob Herring, Mark Rutland,
dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
linux-sunxi-/JYPxA39Uh5TLH3MbocFFw
In-Reply-To: <20170421083857.29636-1-wens-jdAy2FN1RRM@public.gmane.org>
[-- Attachment #1: Type: text/plain, Size: 2338 bytes --]
On Fri, Apr 21, 2017 at 04:38:48PM +0800, Chen-Yu Tsai wrote:
> Hi,
>
> This is v2 of the series previously named "drm/sun4i: Support two
> display pipelines". As the name change suggests, the driver now
> supports any number of pipelines, though the hardware only has
> 2 or 3.
>
> Changes since v1:
>
> - Add component endpoint ID numbering scheme to device tree binding.
>
> - Use lists to keep references to registered backends and tcons.
>
> - Save pointer to device node for backends.
>
> - Traverse the device tree of_graph starting from the tcons, going
> up towards the inputs, and matching the device nodes with the
> device nodes of registered backends, to find the one linked with
> the tcon the search started from.
>
> - Copy the ID for the tcon from its upstream backend, instead of
> trying, and possibly failing, to figure it out from the device
> tree.
>
> - Split out hunk dropping trailing 0 from a backend error message.
>
> Patch 1 adds the component endpoint ID numbering scheme to the
> device tree binding. New in v2.
>
> Patch 2 adds lists to track registered display backends and TCONs,
> instead of just one pointer per component type. Previously added
> arrays of pointers in v1.
>
> Patch 3 drops the trailing 0 from one of the backend's bind error
> messages. This was previously part of the patch "drm/sun4i: Support
> two display pipelines".
>
> Patch 4 adds a function to fetch a backend's ID from the device tree.
> Unchanged.
>
> Patch 5 adds a device node field to the backend data structure and
> saves a reference to the underlying device node of the backend.
> New in v2.
>
> Patch 6 makes the tcon driver find its upstream backend by traversing
> the of_graph and matching device nodes against the device nodes of
> registered backends.
> New in v2.
>
> Patch 7 makes the tcon driver use the ID from its associated backend.
> New in v2. This is not immediately used in this series, but will be
> used in similar fashion for downstream encoders to figure out IDs and
> muxing
>
> Patch 8 adds device nodes for sun6i's second display pipeline.
> Unchanged.
>
> Patch 9 enables sun6i's tcon0 by default.
> Unchanged.
Applied everything, thanks!
Maxime
--
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
^ permalink raw reply
* Re: [PATCH v2 6/9] staging: ccree: add FIPS support
From: Gilad Ben-Yossef @ 2017-04-24 6:06 UTC (permalink / raw)
To: Stephan Müller
Cc: Mark Rutland, devel, Herbert Xu, devicetree, Greg Kroah-Hartman,
Linux kernel mailing list, Binoy Jayan, Rob Herring, linux-crypto,
Gilad Ben-Yossef, Stuart Yoder, David S. Miller, Ofir Drang
In-Reply-To: <CAOtvUMcOib2xr=THj1hy_uPtVhRHgJ2-4__mUBb5VwANQ1GA_A@mail.gmail.com>
On Sun, Apr 23, 2017 at 12:48 PM, Gilad Ben-Yossef <gilad@benyossef.com> wrote:
> Hi,
>
> Thank you for the review.
>
> On Thu, Apr 20, 2017 at 4:39 PM, Stephan Müller <smueller@chronox.de> wrote:
>
>>> +/* The function verifies that tdes keys are not weak.*/
>>> +static int ssi_fips_verify_3des_keys(const u8 *key, unsigned int keylen)
>>> +{
>>> +#ifdef CCREE_FIPS_SUPPORT
>>> + tdes_keys_t *tdes_key = (tdes_keys_t*)key;
>>> +
>>> + /* verify key1 != key2 and key3 != key2*/
>>
>> I do not think that this check is necessary. There is no FIPS requirement or
>> IG that mandates this (unlike the XTS key check).
>>
>> If there would be such requirement, we would need a common service function
>> for all TDES implementations
Well, it turns out there is and we do :-)
This is from crypto/des_generic.c:
/*
* RFC2451:
*
* For DES-EDE3, there is no known need to reject weak or
* complementation keys. Any weakness is obviated by the use of
* multiple keys.
*
* However, if the first two or last two independent 64-bit keys are
* equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
* same as DES. Implementers MUST reject keys that exhibit this
* property.
*
*/
int __des3_ede_setkey(u32 *expkey, u32 *flags, const u8 *key,
unsigned int keylen)
However, this does not check that k1 == k3. In this case DES3
becomes 2DES (2-keys TDEA), the use of which was dropped post 2015
by NIST Special Publication 800-131A*.
Would it be acceptable if I offer a patch adding this check to
__des3_ede_setkey()
and use that in the ccree driver?
* http://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-131Ar1.pdf
Many thanks,
Gilad
--
Gilad Ben-Yossef
Chief Coffee Drinker
"If you take a class in large-scale robotics, can you end up in a
situation where the homework eats your dog?"
-- Jean-Baptiste Queru
_______________________________________________
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http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
^ permalink raw reply
* Re: [PATCH v2 0/3] Add R8A7743/SK-RZG1M PFC support
From: Simon Horman @ 2017-04-24 6:12 UTC (permalink / raw)
To: Sergei Shtylyov
Cc: Rob Herring, Mark Rutland, linux-renesas-soc, devicetree,
Magnus Damm, Russell King, linux-arm-kernel
In-Reply-To: <20170420185132.258111787@cogentembedded.com>
On Thu, Apr 20, 2017 at 09:51:32PM +0300, Sergei Shtylyov wrote:
> Hello.
>
> Here's the set of 3 patches against Simon Horman's 'renesas.git' repo,
> 'renesas-devel-20170420-v4.11-rc7' tag. We're adding the R8A7743 PFC node
> and then describing the pins for SCIF0 and Ether devices declared earlier.
> These patches depend on the R8A7743 PFC suport in order to work properly.
Thanks. I have marked these as deferred pending acceptance of the PFC
driver changes. Please repost or otherwise let me know when dependency
is satisfied.
^ permalink raw reply
* Re: [PATCH v2 6/9] staging: ccree: add FIPS support
From: Stephan Müller @ 2017-04-24 6:16 UTC (permalink / raw)
To: Gilad Ben-Yossef
Cc: Herbert Xu, David S. Miller, Rob Herring, Mark Rutland,
Greg Kroah-Hartman, devel-gWbeCf7V1WCQmaza687I9mD2FQJk+8+b,
linux-crypto-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA, Linux kernel mailing list,
Gilad Ben-Yossef, Binoy Jayan, Ofir Drang, Stuart Yoder
In-Reply-To: <CAOtvUMdF53Bu65oLtDaUKvnxcMCBY1h=Dq8LaPwTGOwg4YKYVg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
Am Montag, 24. April 2017, 08:06:09 CEST schrieb Gilad Ben-Yossef:
Hi Gilad,
>
> Well, it turns out there is and we do :-)
>
> This is from crypto/des_generic.c:
>
> /*
> * RFC2451:
> *
> * For DES-EDE3, there is no known need to reject weak or
> * complementation keys. Any weakness is obviated by the use of
> * multiple keys.
> *
> * However, if the first two or last two independent 64-bit keys are
> * equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
> * same as DES. Implementers MUST reject keys that exhibit this
> * property.
> *
> */
> int __des3_ede_setkey(u32 *expkey, u32 *flags, const u8 *key,
> unsigned int keylen)
>
> However, this does not check that k1 == k3. In this case DES3
> becomes 2DES (2-keys TDEA), the use of which was dropped post 2015
> by NIST Special Publication 800-131A*.
It is correct that the RFC wants at least a 2key 3DES. And it is correct that
SP800-131A mandates 3key 3DES post 2015. All I am saying is that FIPS 140-2
does *not* require a technical verification of the 3 keys being not identical.
Note, formally, FIPS 140-2 requires that the 3 keys (i.e. all 192 bits) must
be obtained from *one* call to a DRBG or KDF (separate independent calls to,
say, obtain one key at a time is *not* permitted). Of course, fixing the
parity bits is allowed after obtaining the random number.
>
> Would it be acceptable if I offer a patch adding this check to
> __des3_ede_setkey()
> and use that in the ccree driver?
I am not sure it makes sense as the core requirement is the *one* invocation
of the DRBG.
Ciao
Stephan
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^ permalink raw reply
* Re: [PATCH v2 6/9] staging: ccree: add FIPS support
From: Stephan Müller @ 2017-04-24 6:21 UTC (permalink / raw)
To: Stephan Müller
Cc: Gilad Ben-Yossef, Herbert Xu, David S. Miller, Rob Herring,
Mark Rutland, Greg Kroah-Hartman,
devel-gWbeCf7V1WCQmaza687I9mD2FQJk+8+b,
linux-crypto-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA, Linux kernel mailing list,
Gilad Ben-Yossef, Binoy Jayan, Ofir Drang, Stuart Yoder
In-Reply-To: <2108964.Kb0ivG6kmD-b2PLbiJbNv8ftSvlWXw0+g@public.gmane.org>
Am Montag, 24. April 2017, 08:16:50 CEST schrieb Stephan Müller:
Hi Gilad,
> >
> > int __des3_ede_setkey(u32 *expkey, u32 *flags, const u8 *key,
> >
> > unsigned int keylen)
> >
> > However, this does not check that k1 == k3. In this case DES3
> > becomes 2DES (2-keys TDEA), the use of which was dropped post 2015
> > by NIST Special Publication 800-131A*.
>
> It is correct that the RFC wants at least a 2key 3DES. And it is correct
> that SP800-131A mandates 3key 3DES post 2015. All I am saying is that FIPS
> 140-2 does *not* require a technical verification of the 3 keys being not
> identical.
One side note: we had discussed a patch to this function in the past, see [1].
[1] https://patchwork.kernel.org/patch/8293441/
Ciao
Stephan
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^ permalink raw reply
* Re: [PATCH v2 6/9] staging: ccree: add FIPS support
From: Gilad Ben-Yossef @ 2017-04-24 7:04 UTC (permalink / raw)
To: Stephan Müller
Cc: Mark Rutland, devel, Herbert Xu, devicetree, Greg Kroah-Hartman,
Linux kernel mailing list, Binoy Jayan, Rob Herring, linux-crypto,
Gilad Ben-Yossef, Stuart Yoder, David S. Miller, Ofir Drang
In-Reply-To: <2108964.Kb0ivG6kmD@tauon.chronox.de>
On Mon, Apr 24, 2017 at 9:16 AM, Stephan Müller <smueller@chronox.de> wrote:
> Am Montag, 24. April 2017, 08:06:09 CEST schrieb Gilad Ben-Yossef:
>
> Hi Gilad,
>>
>> Well, it turns out there is and we do :-)
>>
>> This is from crypto/des_generic.c:
>>
>> /*
>> * RFC2451:
>> *
>> * For DES-EDE3, there is no known need to reject weak or
>> * complementation keys. Any weakness is obviated by the use of
>> * multiple keys.
>> *
>> * However, if the first two or last two independent 64-bit keys are
>> * equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
>> * same as DES. Implementers MUST reject keys that exhibit this
>> * property.
>> *
>> */
>> int __des3_ede_setkey(u32 *expkey, u32 *flags, const u8 *key,
>> unsigned int keylen)
>>
>> However, this does not check that k1 == k3. In this case DES3
>> becomes 2DES (2-keys TDEA), the use of which was dropped post 2015
>> by NIST Special Publication 800-131A*.
>
> It is correct that the RFC wants at least a 2key 3DES. And it is correct that
> SP800-131A mandates 3key 3DES post 2015. All I am saying is that FIPS 140-2
> does *not* require a technical verification of the 3 keys being not identical.
>
> Note, formally, FIPS 140-2 requires that the 3 keys (i.e. all 192 bits) must
> be obtained from *one* call to a DRBG or KDF (separate independent calls to,
> say, obtain one key at a time is *not* permitted). Of course, fixing the
> parity bits is allowed after obtaining the random number.
>>
>> Would it be acceptable if I offer a patch adding this check to
>> __des3_ede_setkey()
>> and use that in the ccree driver?
>
> I am not sure it makes sense as the core requirement is the *one* invocation
> of the DRBG.
Thanks you for the clarification. As I think is obvious by now I am
not a FIPS expert by any stretch.
Isn't the requirements on DRBG or KDF invocations pertain to key
generation only?
What happens if you don't derive the keys on the system, but wish to
use keys derived elsewhere?
I assumed the limitations on weak keys etc. were meant to protect
against that scenario and are
therefore independent from key generation requirements, but I may have
misunderstood that.
Anyway, if I understand you correctly, what you are saying is that
these checks might make an
implementation RFC 2451 and SP800-131A compliant respectively but they
are not required for
FIPS 140-2 compliance? did I understand that correctly?
If so, since two 3DES implementation in the kernel already do the RFC
2451 compliant check I assume
you would not object to the ccree driver using the same function,
disconnect from FIPS being set or
not, just as is being done with the other 3DES implementation.
In addition, would it be OK if we did an extra check in the ccree
driver for SP800-131A key compliance
and disable encryption (but allow decryption) if the key fails the
check? again, this would be independent
from FIPS mode?
Thanks again,
Gilad
--
Gilad Ben-Yossef
Chief Coffee Drinker
"If you take a class in large-scale robotics, can you end up in a
situation where the homework eats your dog?"
-- Jean-Baptiste Queru
_______________________________________________
devel mailing list
devel@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
^ permalink raw reply
* Re: [PATCH v2 6/9] staging: ccree: add FIPS support
From: Gilad Ben-Yossef @ 2017-04-24 7:07 UTC (permalink / raw)
To: Stephan Müller
Cc: Herbert Xu, David S. Miller, Rob Herring, Mark Rutland,
Greg Kroah-Hartman, devel, linux-crypto, devicetree,
Linux kernel mailing list, Gilad Ben-Yossef, Binoy Jayan,
Ofir Drang, Stuart Yoder
In-Reply-To: <2100092.9meQszc5SR@tauon.chronox.de>
On Mon, Apr 24, 2017 at 9:21 AM, Stephan Müller <smueller@chronox.de> wrote:
> Am Montag, 24. April 2017, 08:16:50 CEST schrieb Stephan Müller:
>
> Hi Gilad,
>
>> >
>> > int __des3_ede_setkey(u32 *expkey, u32 *flags, const u8 *key,
>> >
>> > unsigned int keylen)
>> >
>> > However, this does not check that k1 == k3. In this case DES3
>> > becomes 2DES (2-keys TDEA), the use of which was dropped post 2015
>> > by NIST Special Publication 800-131A*.
>>
>> It is correct that the RFC wants at least a 2key 3DES. And it is correct
>> that SP800-131A mandates 3key 3DES post 2015. All I am saying is that FIPS
>> 140-2 does *not* require a technical verification of the 3 keys being not
>> identical.
>
> One side note: we had discussed a patch to this function in the past, see [1].
>
> [1] https://patchwork.kernel.org/patch/8293441/
>
Thanks, I was not aware of that.
I guess we could change the function to indicate that a key is valid
for decryption but not encryption
and have the implementation limiting based on that if there is an
interest in SP800-131A compliance.
Gilad
--
Gilad Ben-Yossef
Chief Coffee Drinker
"If you take a class in large-scale robotics, can you end up in a
situation where the homework eats your dog?"
-- Jean-Baptiste Queru
^ permalink raw reply
* Re: Re: [PATCH v3 02/12] arm64: allwinner: a64: add NMI controller on A64
From: Maxime Ripard @ 2017-04-24 7:17 UTC (permalink / raw)
To: icenowy-h8G6r0blFSE
Cc: Lee Jones, Rob Herring, Chen-Yu Tsai, Liam Girdwood, Mark Brown,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r,
linux-sunxi-/JYPxA39Uh5TLH3MbocFFw
In-Reply-To: <18ae853e9ce59a83bdeb6b64f96caee0-h8G6r0blFSE@public.gmane.org>
[-- Attachment #1: Type: text/plain, Size: 4052 bytes --]
On Thu, Apr 20, 2017 at 03:03:38PM +0800, icenowy-h8G6r0blFSE@public.gmane.org wrote:
> 在 2017-04-20 13:58，Maxime Ripard 写道：
> > On Tue, Apr 18, 2017 at 06:56:43PM +0800, Icenowy Zheng wrote:
> > >
> > >
> > > 于 2017年4月18日 GMT+08:00 下午3:00:16, Maxime Ripard
> > > <maxime.ripard-wi1+55ScJUtKEb57/3fJTNBPR1lH4CV8@public.gmane.org> 写到:
> > > >On Mon, Apr 17, 2017 at 07:57:37PM +0800, Icenowy Zheng wrote:
> > > >> Allwinner A64 SoC features a NMI controller, which is usually
> > > >connected
> > > >> to the AXP PMIC.
> > > >>
> > > >> Add support for it.
> > > >>
> > > >> Signed-off-by: Icenowy Zheng <icenowy-h8G6r0blFSE@public.gmane.org>
> > > >> Acked-by: Chen-Yu Tsai <wens-jdAy2FN1RRM@public.gmane.org>
> > > >> ---
> > > >> Changes in v2:
> > > >> - Added Chen-Yu's ACK.
> > > >>
> > > >> arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 8 ++++++++
> > > >> 1 file changed, 8 insertions(+)
> > > >>
> > > >> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> > > >b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> > > >> index 05ec9fc5e81f..53c18ca372ea 100644
> > > >> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> > > >> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> > > >> @@ -403,6 +403,14 @@
> > > >> <GIC_SPI 41 IRQ_TYPE_LEVEL_HIGH>;
> > > >> };
> > > >>
> > > >> + nmi_intc: interrupt-controller@01f00c0c {
> > > >> + compatible = "allwinner,sun6i-a31-sc-nmi";
> > > >> + interrupt-controller;
> > > >> + #interrupt-cells = <2>;
> > > >> + reg = <0x01f00c0c 0x38>;
> > > >
> > > >The base address is not correct, and there's uncertainty on whether
> > > >this is this particular controller or not. Did you even test this?
> > >
> > > Tested by axp20x-pek.
> >
> > Still, the base address is wrong, which is yet another hint that this
> > is not the same interrupt controller, and just works by accident.
>
> No, it's the same as other post-sun6i device trees.
> See other post-sun6i device trees: (or maybe they're all wrong, but
> as we have no document for it, we should temporarily keep them)
>
> sun6i-a31.dtsi
> ```
> nmi_intc: interrupt-controller@01f00c0c {
> compatible = "allwinner,sun6i-a31-sc-nmi";
> interrupt-controller;
> #interrupt-cells = <2>;
> reg = <0x01f00c0c 0x38>;
> interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>;
> };
> ```
>
> sun8i-a23-a33.dtsi
> ```
> nmi_intc: interrupt-controller@01f00c0c {
> compatible = "allwinner,sun6i-a31-sc-nmi";
> interrupt-controller;
> #interrupt-cells = <2>;
> reg = <0x01f00c0c 0x38>;
> interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>;
> };
> ```
>
> But according to the BSP device tree, the base address should be
> 0x01f00c00. Should I send some patch to fix all of them? (but it will
> break device tree compatibility)
I'm really not a big fan of "if we see something that is broken, just
let it rot" to be honest.
We have no idea how this controller works exactly, just like we have
no idea if it is exactly the same controller or not.
The only thing we have today is the memory map, and it tells us that
it has more registers than what you express here.
Because of the DT backward compatibility, you have to think of it the
other way around: what will happen if it turns out we need to setup
any register outside of that region you described in the DT, in
something like a year or so?
We can't, really. While if you have the full memory region from the
beginning, then you just have to add a single writel in your driver.
Maxime
--
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Embedded Linux and Kernel engineering
http://free-electrons.com
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^ permalink raw reply
* Re: [PATCH v2 6/9] staging: ccree: add FIPS support
From: Stephan Müller @ 2017-04-24 7:22 UTC (permalink / raw)
To: Gilad Ben-Yossef
Cc: Mark Rutland, devel, Herbert Xu, devicetree, Greg Kroah-Hartman,
Linux kernel mailing list, Binoy Jayan, Rob Herring, linux-crypto,
Gilad Ben-Yossef, Stuart Yoder, David S. Miller, Ofir Drang
In-Reply-To: <CAOtvUMfOM0fG+NCX=FcqDZfZ0k54Fcie+dcikxRaFjmfubYkKQ@mail.gmail.com>
Am Montag, 24. April 2017, 09:04:13 CEST schrieb Gilad Ben-Yossef:
Hi Gilad,
>
> Thanks you for the clarification. As I think is obvious by now I am
> not a FIPS expert by any stretch.
>
> Isn't the requirements on DRBG or KDF invocations pertain to key
> generation only?
> What happens if you don't derive the keys on the system, but wish to
> use keys derived elsewhere?
> I assumed the limitations on weak keys etc. were meant to protect
> against that scenario and are
> therefore independent from key generation requirements, but I may have
> misunderstood that.
That is exactly an important question. NIST lately moved away from a pure
cipher-only view of cryptography to a more holistic view (i.e. where are
ciphers used).
That said, for 3DES there is no formal requirement that the 3 keys must be
checked. NIST is fine when documentation says how the keys are generated by
some logic outside the module.
>
> Anyway, if I understand you correctly, what you are saying is that
> these checks might make an
> implementation RFC 2451 and SP800-131A compliant respectively but they
> are not required for
> FIPS 140-2 compliance? did I understand that correctly?
Correct. Regarding SP800-131A, it only says that a full 3key 3DES is required.
It does not say whether/how the key shall be enforced not being identical.
>
> If so, since two 3DES implementation in the kernel already do the RFC
> 2451 compliant check I assume
> you would not object to the ccree driver using the same function,
> disconnect from FIPS being set or
> not, just as is being done with the other 3DES implementation.
Absolutely. If possible, all 3DES implementations should use the same checking
functions. The existing checking function regarding the prevention of 1key
3DES should be used by your code too.
All I am saying that from a FIPS perspective, there is no need to extent the
common function by a 3key 3DES enforcer.
>
> In addition, would it be OK if we did an extra check in the ccree
> driver for SP800-131A key compliance
> and disable encryption (but allow decryption) if the key fails the
> check? again, this would be independent
> from FIPS mode?
My personal taste would be: changes that makes sense for all 3DES
implementations should go to a common function. Otherwise, 3DES implementation
A behaves differently than impl. B.
That said, having a check that all three keys are non-identical would
certainly be good (see my Ack to the patch from a year ago). But you cannot
use the argument that FIPS mandates it to push it through. :-)
Ciao
Stephan
PS: There is currently a new requirement being discussed for FIPS: 3DES
operations should not allow more than 4GB of data to be encrypted with one
key. This requirement would need technical enforcement. I am looking into this
one for some time now.
^ permalink raw reply
* Re: [PATCH v2 6/9] staging: ccree: add FIPS support
From: Stephan Müller @ 2017-04-24 7:23 UTC (permalink / raw)
To: Gilad Ben-Yossef
Cc: Herbert Xu, David S. Miller, Rob Herring, Mark Rutland,
Greg Kroah-Hartman, devel-gWbeCf7V1WCQmaza687I9mD2FQJk+8+b,
linux-crypto-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA, Linux kernel mailing list,
Gilad Ben-Yossef, Binoy Jayan, Ofir Drang, Stuart Yoder
In-Reply-To: <CAOtvUMdYtLa10dUQ--5hxeYOAi+vw9OTLZF=WPmDS27cr6KvJg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
Am Montag, 24. April 2017, 09:07:45 CEST schrieb Gilad Ben-Yossef:
Hi Gilad,
> I guess we could change the function to indicate that a key is valid
> for decryption but not encryption
> and have the implementation limiting based on that if there is an
> interest in SP800-131A compliance.
I would be delighted to see and review a patch.
Ciao
Stephan
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^ permalink raw reply
* Re: [PATCH/RFC 0/5] arm64: dts: renesas: Break out common board support
From: Geert Uytterhoeven @ 2017-04-24 7:25 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Simon Horman, Magnus Damm, Kuninori Morimoto, Yoshihiro Shimoda,
Rob Herring, Mark Rutland, Linux-Renesas,
devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org
In-Reply-To: <1492779321-23939-1-git-send-email-geert+renesas@glider.be>
On Fri, Apr 21, 2017 at 2:55 PM, Geert Uytterhoeven
<geert+renesas@glider.be> wrote:
> Geert Uytterhoeven (5):
> arm64: renesas: r8a7796: Add external audio clocks
> arm64: renesas: r8a7796: Add external PCIe bus clock
Oops, the above should have had the proper "arm64: dts:" prefix.
> [RFC] arm64: dts: r8a7796: Add placeholders for various devices
> [RFC] arm64: dts: renesas: Extract common Salvator-X board support
> [RFC] arm64: dts: renesas: Extract common ULCB board support
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
^ permalink raw reply
* Re: [PATCH] ARM: at91/at91-pinctrl documentation: fix spelling mistake: "contoller" -> "controller"
From: Nicolas Ferre @ 2017-04-24 8:19 UTC (permalink / raw)
To: Colin King, Linus Walleij, Rob Herring, Mark Rutland,
linux-gpio-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA
Cc: kernel-janitors-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <20170421120713.4939-1-colin.king-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
Le 21/04/2017 à 14:07, Colin King a écrit :
> From: Colin Ian King <colin.king-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
>
> trivial fix to spelling mistake in documentation
>
> Signed-off-by: Colin Ian King <colin.king-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
Acked-by: Nicolas Ferre <nicolas.ferre-UWL1GkI3JZL3oGB3hsPCZA@public.gmane.org>
> ---
> Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt
> index 9a8a45d9d8ab..590e60378be3 100644
> --- a/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt
> +++ b/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt
> @@ -4,7 +4,7 @@ The AT91 Pinmux Controller, enables the IC
> to share one PAD to several functional blocks. The sharing is done by
> multiplexing the PAD input/output signals. For each PAD there are up to
> 8 muxing options (called periph modes). Since different modules require
> -different PAD settings (like pull up, keeper, etc) the contoller controls
> +different PAD settings (like pull up, keeper, etc) the controller controls
> also the PAD settings parameters.
>
> Please refer to pinctrl-bindings.txt in this directory for details of the
>
--
Nicolas Ferre
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^ permalink raw reply
* Re: [PATCH V5 3/7] ARM: exynos: Use - instead of @ for DT OPP entries
From: Masahiro Yamada @ 2017-04-24 8:30 UTC (permalink / raw)
To: Krzysztof Kozlowski
Cc: Viresh Kumar, arm, Chanwoo Choi, MyungJoo Ham, Kyungmin Park,
Kukjin Kim, Javier Martinez Canillas, Rob Herring, Mark Rutland,
linaro-kernel, linux-arm-kernel, linux-pm, Rafael Wysocki,
Rob Herring, linux-samsung-soc, devicetree,
Linux Kernel Mailing List
In-Reply-To: <20170420160930.halyszjunt4q2634@kozik-lap>
2017-04-21 1:09 GMT+09:00 Krzysztof Kozlowski <krzk@kernel.org>:
> On Thu, Apr 20, 2017 at 04:25:07PM +0530, Viresh Kumar wrote:
>> Compiling the DT file with W=1, DTC warns like follows:
>>
>> Warning (unit_address_vs_reg): Node /opp_table0/opp@1000000000 has a
>> unit name, but no reg property
>>
>> Fix this by replacing '@' with '-' as the OPP nodes will never have a
>> "reg" property.
>>
>> Reported-by: Krzysztof Kozlowski <krzk@kernel.org>
>> Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
>> Suggested-by: Mark Rutland <mark.rutland@arm.com>
>> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
>> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
>> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
>> Acked-by: Rob Herring <robh@kernel.org>
>> ---
>> .../devicetree/bindings/devfreq/exynos-bus.txt | 46 +++++++--------
>> arch/arm/boot/dts/exynos3250.dtsi | 46 +++++++--------
>> arch/arm/boot/dts/exynos4210.dtsi | 32 +++++------
>> arch/arm/boot/dts/exynos4412-prime.dtsi | 4 +-
>> arch/arm/boot/dts/exynos4412.dtsi | 66 +++++++++++-----------
>> arch/arm/boot/dts/exynos5420.dtsi | 40 ++++++-------
>> arch/arm/boot/dts/exynos5800.dtsi | 56 +++++++++---------
>> arch/arm64/boot/dts/exynos/exynos5433-bus.dtsi | 48 ++++++++--------
>> arch/arm64/boot/dts/exynos/exynos5433.dtsi | 50 ++++++++--------
>> 9 files changed, 194 insertions(+), 194 deletions(-)
>
>
> Thanks, split ARM64 from ARM and applied (for v4.12). arm-soc keeps DTS
> separated between ARM architectures. Technically this should require a
> resend but we had way too many resends for this simple patch.
>
Minor note:
For arm64 part, Krzysztof's Signed-off-by is doubled.
(commit 5dccc9873c4af60f4478b3ef54267353f25cc301)
--
Best Regards
Masahiro Yamada
^ permalink raw reply
* Re: [PATCH V5 3/7] ARM: exynos: Use - instead of @ for DT OPP entries
From: Krzysztof Kozlowski @ 2017-04-24 8:32 UTC (permalink / raw)
To: Masahiro Yamada
Cc: Viresh Kumar, arm, Chanwoo Choi, MyungJoo Ham, Kyungmin Park,
Kukjin Kim, Javier Martinez Canillas, Rob Herring, Mark Rutland,
linaro-kernel, linux-arm-kernel, linux-pm, Rafael Wysocki,
Rob Herring, linux-samsung-soc, devicetree,
Linux Kernel Mailing List
In-Reply-To: <CAK7LNAQChtyRzKoSWCFakg+3_Qp_NZoXP1pEt6edDQrnL9FQ2w@mail.gmail.com>
On Mon, Apr 24, 2017 at 10:30 AM, Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
> 2017-04-21 1:09 GMT+09:00 Krzysztof Kozlowski <krzk@kernel.org>:
>> On Thu, Apr 20, 2017 at 04:25:07PM +0530, Viresh Kumar wrote:
>>> Compiling the DT file with W=1, DTC warns like follows:
>>>
>>> Warning (unit_address_vs_reg): Node /opp_table0/opp@1000000000 has a
>>> unit name, but no reg property
>>>
>>> Fix this by replacing '@' with '-' as the OPP nodes will never have a
>>> "reg" property.
>>>
>>> Reported-by: Krzysztof Kozlowski <krzk@kernel.org>
>>> Reported-by: Masahiro Yamada <yamada.masahiro@socionext.com>
>>> Suggested-by: Mark Rutland <mark.rutland@arm.com>
>>> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
>>> Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
>>> Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
>>> Acked-by: Rob Herring <robh@kernel.org>
>>> ---
>>> .../devicetree/bindings/devfreq/exynos-bus.txt | 46 +++++++--------
>>> arch/arm/boot/dts/exynos3250.dtsi | 46 +++++++--------
>>> arch/arm/boot/dts/exynos4210.dtsi | 32 +++++------
>>> arch/arm/boot/dts/exynos4412-prime.dtsi | 4 +-
>>> arch/arm/boot/dts/exynos4412.dtsi | 66 +++++++++++-----------
>>> arch/arm/boot/dts/exynos5420.dtsi | 40 ++++++-------
>>> arch/arm/boot/dts/exynos5800.dtsi | 56 +++++++++---------
>>> arch/arm64/boot/dts/exynos/exynos5433-bus.dtsi | 48 ++++++++--------
>>> arch/arm64/boot/dts/exynos/exynos5433.dtsi | 50 ++++++++--------
>>> 9 files changed, 194 insertions(+), 194 deletions(-)
>>
>>
>> Thanks, split ARM64 from ARM and applied (for v4.12). arm-soc keeps DTS
>> separated between ARM architectures. Technically this should require a
>> resend but we had way too many resends for this simple patch.
>>
>
>
> Minor note:
>
> For arm64 part, Krzysztof's Signed-off-by is doubled.
> (commit 5dccc9873c4af60f4478b3ef54267353f25cc301)
Thanks for spotting it.
Best regards,
Krzysztof
^ permalink raw reply
* [PATCH v14 00/11] mux controller abstraction and iio/i2c muxes
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: Jonathan Cameron, linux-kernel-u79uwXL29TY76Z2rM5mHXA,
Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Hartmut Knaack, Lars-Peter Clausen, Peter Meerwald-Stadler,
Jonathan Corbet, linux-i2c-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
linux-doc-u79uwXL29TY76Z2rM5mHXA, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel-bIcnvbaLZ9MEGnE8C9+IrQ
Hi!
The big change since v13 is that the mux state is now locked with a mutex
instead of an rwsem. Other that that, it is mostly restructuring and doc
changes. There are a few other "real" changes as well, but those changes
feel kind of minor. I guess what I'm trying to say is that although the
list of changes for v14 is longish, it's still basically the same as last
time.
Jonathan, I hope it was OK to keep your Reviewed-by tag on patch 03/11
(mux-core.c plus support) and to also add it to 04/11 (mux-gpio.c) even
if the previously reviewed patch (mux-core.c + mux-gpio.c) was split in
two?
v13 -> v14 changes
- Go back to a mutex instead of a rwsem to protect the mux state. [Greg K-H]
- Add __must_check to the mux_control_select function. [Greg, was this what
you meant with "sparse markings"? I assume not, but I don't know...]
- Don't return hint on mux state changes when calling mux_control_select. [Greg]
- Add mux_control_try_select function. [Philipp Zabel]
- Split the mux.h #include into mux/driver.h and mux/consumer.h [Philipp]
- Add mux_control_states function to be able to completely hide struct
mux_control details from mux consumers.
- Include the constants from the DT bindings include, instead of
redefining them. [Greg]
- Make mux_chip_alloc (and devm_mux_chip_alloc) return ERR_PTR instead
of NULL on error. [Greg]
- Document why mux_chip_alloc and mux_chip_register are split up, and
what is supposed to happen between the two calls, [Greg] and...
- ...specifically mention that mux drivers should never clobber
cached_state [Philipp].
- Support module unloading of the core (and initialize mux_ida on init). [Greg]
- Do not mention link order when commenting on why there is a subsys_initcall
instead of an ordinare module_init in the mux-core. [Greg]
- Use __func__ instead of spelling out the function name. [Greg]
- Drop cargo cult usage of WARN_ON. [Greg]
- Drop unused forward declaration of struct platform_device.
- Move kernel doc from the function declarations to the definitions. [Greg]
- Use unsigned values for the state in the consumer interface. [Philipp]
- WARN if consumers request an invalid state. [Philipp]
- Split out mux-gpio from the core patch (03/10 -> 03/11 and 04/11). [Greg]
- Drop OF Kconfig dep from mux-gpio. [Greg]
- Fail the adg792a probe if the I2C adapter does not support
I2C_FUNC_SMBUS_BYTE_DATA.
- For clarity, handle the adg792a active low reset bit in a helper function.
- Make use of the preexisting mux variable in the adg792a driver instead of
chasing the same pointers a second time.
- Use device_property_read_* instead of of_property_read_* in adg792a.
- Added a "thank you" section to the patch adding the mux core (patch 03/11).
This adds a new mux controller subsystem with an interface for accessing
mux controllers, along with two drivers providing the interface (gpio
and adg792) and two consumers (iio and i2c). This is done in such a way
that several consumers can independently access the same mux controller
if one controller controls several multiplexers, thus allowing sharing.
But sharing is by no means required, of course. It is perfectly fine to
have a single consumer of a dedicated mux controller controlling only
one mux for said consumer.
The prediction is that the typical use case will be for gpio-based muxing
(which is also what drove the development), where the below schematics
show the flexibility with one gpio-based mux controller being shared by
the iio-mux and i2c-mux-gpmux drivers.
.----.
|GPO0|----------.
|GPO1|--------. |
| | | |
| | .-------.
| | |dg4052a|
| | | |
|ADC0|-----|X X0|---- signal X0
| | | X1|---- signal X1
| | | X2|---- signal X2
| | | X3|---- signal X3
| | | |
|SDA0|-----|Y Y0|---- i2c segment Y0
|SCL0|--. | Y1|---- i2c segment Y1
'----' | | Y2|---- i2c segment Y2
| | Y3|---- i2c segment Y3
| '-------'
| 0 1 2 3 (feed SCL0 to each of
| | | | | the 4 muxed segments)
'----------------+-+-+-'
GPO0 and GPO1 may also be fed to further parallel muxers, which is perhaps
desired in a real application to minimize digital noise from the I2C Y
channel leaking into the analog X channel. I.e. it might be a good idea
to separate the analog and digital signals...
And the below hypothetical schematics indicate something similar but using
the I2C-based adg792a multiplexer instead.
.----.
|SDA0|----------.
|SCL0|--------. |
| | | |
| | .-------.
| | |adg792a|
| | | |
|ADC0|-----|D1 S1A|---- signal S1A
| | | S1B|---- signal S1B
| | | S1C|---- signal S1C
| | | S1D|---- signal S1D
| | | |
|SDA1|---+-|D2 S2A|---- i2c segment S2A
|SCL1|-. | | S2B|---- i2c segment S2B
'----' | | | S2C|---- i2c segment S2C
| | | S2D|---- i2c segment S2D
| | | |
| '-|D3 S3A|---- i2c segment S3A
| | S3B|---- i2c segment S3B
| | S3C|---- i2c segment S3C
| | S3D|---- i2c segment S3D
| '-------'
| A B C D A B C D (feed SCL1 to each of
| | | | | | | | | the 8 muxed segments)
'-----------------+-+-+-+---+-+-+-'
Background:
I have a piece of hardware that is using the same 3 GPIO pins
to control four 8-way muxes. Three of them control ADC lines
to an ADS1015 chip with an iio driver, and the last one
controls the SDA line of an i2c bus. We have some deployed
code to handle this, but you do not want to see it or ever
hear about it. I'm not sure why I even mention it. Anyway,
the situation has nagged me to no end for quite some time.
So, after first getting more intimate with the i2c muxing code
and later discovering the drivers/iio/inkern.c file and
writing a couple of drivers making use of it, I came up with
what I think is an acceptable solution; add a generic mux
controller driver (and subsystem) that is shared between all
instances, and combine that with an iio mux driver and a new
general purpose i2c mux driver that is only hooking the i2c
muxing and the new mux controller.
One thing that I would like to do, but don't see a solution
for, is to move the mux control code that is present in
various drivers in drivers/i2c/muxes to this new minimalistic
muxing subsystem, thus converting all present i2c muxes (but
perhaps not gates and arbitrators).
I'm using an ordinary mutex to lock the mux, but that isn't
really a perfect fit since multiple consumers of the same
mux controller need not lock each other out when they want
the same mux state. I had a rwsem for a long while, but that
still degenerated to the above mutex case both when there was
contention and for a race when uncontended.
Also, the "mux" name feels a bit ambitious, there are many muxes
in the world, and this tiny bit of code is probably not good
enough to be a nice fit for all...
Older changes:
v12 -> v13 changes: https://lkml.org/lkml/2017/4/13/493
- Philipp Zabel noticed a bad compatible string in the gpio muxer.
I amended patch 3/10 with his patch.
- Fixed reversed sense of the reset bit in the adg792 muxer (patch 10/10).
v11 -> v12 changes: https://lkml.org/lkml/2017/3/27/464
- patches 11 and 12 folded into patches 6 and 3 respectively.
v10 -> v11 changes: https://lkml.org/lkml/2017/3/27/336
- added a fixes-tag and an ack from Jonathan on patch 11
- added a new patch (12) with a fix for messed up error path reported
by Paul Gortmaker.
- fixed some editorial nitpicks in the documentation comments in patch 3.
v9 -> v10 changes: https://lkml.org/lkml/2017/3/10/411
- rebased onto v4.11-rc1
- added reviewed-by tags from Rob on patches 7 and 9
- added a new patch (11) with a fix for an unsigned compare with less than
zero detected by CoverityScan and reported by Colin Ian King
- allowed the mux core to be built as a module, after discussion with Paul
Gortmaker
- added explicit includes of linux/export.h and linux/init.h from the mux
core, also noted by Paul
- fixed trivial whitespace issue in drivers/mux/Makefile
- added trailing '>' after my mail address in MODULE_AUTHOR, which was missing
in all new modules in drivers/mux
v8 -> v9 changes: https://lkml.org/lkml/2017/2/8/394
- dropped the suffix from the compatible string of the i2c-mux-simple
binding (was ,mux-locked or ,parent-locked) and add an optional
mux-locked property instead to change the desired locking behavior
from the default parent-locked
- add description of the difference between mux-locked and parent-locked
- renamed i2c-mux-simple to i2c-mux (bindings for this general purpose
i2c mux are in i2c-mux-gpmux.txt since i2c-mux.txt is already occupied
by the common i2c-mux bindings)
- changed compatible from mux-gpio to gpio-mux
- changed bindings for idle-state back to a single array, but add defines
for as-is and hi-Z thus avoiding magic numbers
- make use of the above defines in the code as well
- make idle-state a common mux property described in mux-controller.txt
instead of repeating the info in individual mux controller bindings
- drop the adi,parallel property from the adg792 bindings and piggy-back
on the #mux-control-cells property
- refrain from using the compatible string as node name
- dropped the simplified bindings for single-user gpio mux
- added acks on patches 2/10 and 5/10 from Rob
v7 -> v8 changes: https://lkml.org/lkml/2017/1/18/745
- cleanup the implementation of the simplified gpio bindings, but still...
- ...reorder patches so that they appear last in the series (patches 11
and 12 were patches 4 and 5 in v7) since Jonathan convinced me that
they were perhaps not such a good idea after all. But I still wanted
to show the last version I had and I'm still a bit undecided...
- added some words to the remaining otherwise empty commit messages
- added various acks/reviews from Jonathan and Wolfram.
- move mux last in drivers/Kconfig and drivers/Makefile
- bump copyright years
- centralize error reporting of common operatinons to the mux core
- add WARN_ON for faulty usage of mux_chip_register
- simplify code for other WARN_ON call sites
v6 -> v7 changes: https://lkml.org/lkml/2017/1/4/315
- move from drivers/misc/mux-* to drivers/mux/
[I will remove Cc:s to Arnd and Greg for v8, when/if that happens]
- add managed versions of mux_chip_alloc and mux_chip_register
- use the above in mux-gpio.c and mux-adg792a.c
- also use them to support a simplified binding of a gpio mux for the common
case where there is a single consumer (and no specific idle requirements)
- new binding for describing idle behaviour of mux-adg792a
- add bindings for the gpo-pins on the mux-adg792g
- use device_property_read_u32 instead of of_property_read_u32 in mux-gpio.c
- rename iio mux compatible to io-channel-mux (was iio-mux)
- remove linuxism in the bindings (it was mentioning a function name)
- add missing quote in the example in the io-channel-mux binding
- factor out preparatory cleanup of devres docs to its own patch
- add blank line in mux_chip_free
- use SIMPLE_{PARENT,MUX}_LOCKED instead of magic numbers {0,1} in
i2c-mux-simple.c
- add some acks and a reviewed-by from Jonathan
v5 -> v6 changes: https://lkml.org/lkml/2016/11/30/466
- fix stupidity in mux_chip_priv, mux_gpio_remove and adg792a_remove.
- change the devicetree bindings for the iio-mux to use a list of strings
(channels property) instead of a list children.
v4 -> v5 changes: https://lkml.org/lkml/2016/11/29/224
- remove support for fancier dt layouts and go back to the phandle
approach from v2 and before, killing the horrible non-working
refcounting crap from v4 and avoiding a bunch of life-time issues
in v3.
- introduce the concept of a mux-chip, that can hold one or more
mux-controllers (inspired by the pwm subsystem).
- add dt #mux-control-cells property needed to get to the desired
mux controller if a mux chip provides more than one.
- take away the option to build the mux-core as a module.
- if the mux controller has an idle state, make sure the mux controller
is set up in the idle state initially (when it should be idle).
- do not use a variable length array on the stack in mux_gpio_set to
temporarily store the gpio state, preallocate space instead.
- fix resource leak on one failure path in mux_gpio_probe.
- driver for Analog Devices ADG792A/G, literally the first mux chip
I found on the Internet with an i2c interface (that was not a
dedicated i2c multiplexer like PCA9547) which I used to verify
that the abstractions in the mux core are up to the task. Untested,
just proof of concept that at least looks pretty and compiles...
- various touch-ups.
v3 -> v4 changes: https://lkml.org/lkml/2016/11/24/664
- rebased onto next-20161122 (depends on recent _available iio changes).
- added support for having the mux-controller in a child node of a
mux-consumer if it is a sole consumer, to hopefully even further satisfy
the complaint from Rob (and later Lars-Peter) about dt complexity.
- the above came at the cost of some rather horrible refcounting code,
please review and suggest how it should be done...
- changed to register a device class instead of a bus.
- pass in the parent device into mux_control_alloc and require less
work from mux-control drivers.
- changed device names from mux:control%d to mux%d
- move kernel-doc from mux-core.c to mux.h (and add some bits).
- give the gpio driver a chance to update all mux pins at once.
- factor out iio ext_info lookup into new helper function. /Lars-Peter
- use an unsigned type for the iio ext_info count. /Lars-Peter
- unified "brag strings" in the file headers.
v2 -> v3 changes: https://lkml.org/lkml/2016/11/21/332
- have the mux-controller in the parent node of any mux-controller consumer,
to hopefully satisfy complaint from Rob about dt complexity.
- improve commit message of the mux subsystem commit, making it more
general, as requested by Jonathan.
- remove priv member from struct mux_control and calculate it on the
fly. /Jonathan
- make the function comments in mux-core.c kernel doc. /Jonathan
- add devm_mux_control_* to Documentation/driver.model/devres.txt. /Jonathan
- add common dt bindings for mux-controllers, refer to them from the
mux-gpio bindings. /Rob
- clarify how the gpio pins map to the mux state. /Rob
- separate CONFIG_ variables for the mux core and the mux gpio driver.
- improve Kconfig help texts.
- make CONFIG_MUX_GPIO depend on CONFIG_GPIOLIB.
- keep track of the number of mux states in the mux core.
- since the iio channel number is used as mux state, it was possible
to drop the state member from the mux_child struct.
- cleanup dt bindings for i2c-mux-simple, it had some of copy-paste
problems from ots origin (i2c-mux-gpio).
- select the mux control subsystem in config for the i2c-mux-simple driver.
- add entries to MAINTAINERS and my sign-off, I'm now satisfied and know
nothing in this to be ashamed of.
v1 -> v2 changes: https://lkml.org/lkml/2016/11/17/918
- fixup export of mux_control_put reported by kbuild
- drop devicetree iio-ext-info property as noted by Lars-Peter,
and replace the functionality by exposing all ext_info
attributes of the parent channel for each of the muxed
channels. A cache on top of that and each muxed channel
gets its own view of the ext_info of the parent channel.
- implement idle-state for muxes
- clear out the cache on failure in order to force a mux
update on the following use
- cleanup the probe of i2c-mux-simple driver
- fix a bug in the i2c-mux-simple driver, where failure in
the selection of the mux caused a deadlock when the mux
was later unconditionally deselected.
v1: https://lkml.org/lkml/2016/11/16/812
Cheers,
peda
Peter Rosin (11):
devres: trivial whitespace fix
dt-bindings: document devicetree bindings for mux-controllers and
gpio-mux
mux: minimal mux subsystem
mux: gpio: add mux controller driver for gpio based multiplexers
iio: inkern: api for manipulating ext_info of iio channels
dt-bindings: iio: io-channel-mux: document io-channel-mux bindings
iio: multiplexer: new iio category and iio-mux driver
dt-bindings: i2c: i2c-mux: document general purpose i2c-mux bindings
i2c: i2c-mux-gpmux: new driver
dt-bindings: mux-adg792a: document devicetree bindings for ADG792A/G
mux
mux: adg792a: add mux controller driver for ADG792A/G
Documentation/ABI/testing/sysfs-class-mux | 16 +
.../devicetree/bindings/i2c/i2c-mux-gpmux.txt | 99 ++++
.../bindings/iio/multiplexer/io-channel-mux.txt | 39 ++
.../devicetree/bindings/mux/adi,adg792a.txt | 75 +++
Documentation/devicetree/bindings/mux/gpio-mux.txt | 69 +++
.../devicetree/bindings/mux/mux-controller.txt | 157 ++++++
Documentation/driver-model/devres.txt | 10 +-
MAINTAINERS | 16 +
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/i2c/muxes/Kconfig | 13 +
drivers/i2c/muxes/Makefile | 1 +
drivers/i2c/muxes/i2c-mux-gpmux.c | 173 ++++++
drivers/iio/Kconfig | 1 +
drivers/iio/Makefile | 1 +
drivers/iio/inkern.c | 60 +++
drivers/iio/multiplexer/Kconfig | 18 +
drivers/iio/multiplexer/Makefile | 6 +
drivers/iio/multiplexer/iio-mux.c | 459 ++++++++++++++++
drivers/mux/Kconfig | 46 ++
drivers/mux/Makefile | 7 +
drivers/mux/mux-adg792a.c | 157 ++++++
drivers/mux/mux-core.c | 593 +++++++++++++++++++++
drivers/mux/mux-gpio.c | 114 ++++
include/dt-bindings/mux/mux.h | 16 +
include/linux/iio/consumer.h | 37 ++
include/linux/mux/consumer.h | 33 ++
include/linux/mux/driver.h | 111 ++++
28 files changed, 2329 insertions(+), 1 deletion(-)
create mode 100644 Documentation/ABI/testing/sysfs-class-mux
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
create mode 100644 Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt
create mode 100644 Documentation/devicetree/bindings/mux/adi,adg792a.txt
create mode 100644 Documentation/devicetree/bindings/mux/gpio-mux.txt
create mode 100644 Documentation/devicetree/bindings/mux/mux-controller.txt
create mode 100644 drivers/i2c/muxes/i2c-mux-gpmux.c
create mode 100644 drivers/iio/multiplexer/Kconfig
create mode 100644 drivers/iio/multiplexer/Makefile
create mode 100644 drivers/iio/multiplexer/iio-mux.c
create mode 100644 drivers/mux/Kconfig
create mode 100644 drivers/mux/Makefile
create mode 100644 drivers/mux/mux-adg792a.c
create mode 100644 drivers/mux/mux-core.c
create mode 100644 drivers/mux/mux-gpio.c
create mode 100644 include/dt-bindings/mux/mux.h
create mode 100644 include/linux/mux/consumer.h
create mode 100644 include/linux/mux/driver.h
--
2.1.4
^ permalink raw reply
* [PATCH v14 01/11] devres: trivial whitespace fix
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel-u79uwXL29TY76Z2rM5mHXA, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet,
linux-i2c-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
linux-doc-u79uwXL29TY76Z2rM5mHXA, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel-bIcnvbaLZ9MEGnE8C9+IrQ
In-Reply-To: <1493022995-16917-1-git-send-email-peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
Everything else is indented with two spaces, so fix the odd one out.
Acked-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Signed-off-by: Peter Rosin <peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
---
Documentation/driver-model/devres.txt | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index bf34d5b3a733..efb8200819d6 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -335,7 +335,7 @@ MEM
devm_kzalloc()
MFD
- devm_mfd_add_devices()
+ devm_mfd_add_devices()
PER-CPU MEM
devm_alloc_percpu()
--
2.1.4
^ permalink raw reply related
* [PATCH v14 02/11] dt-bindings: document devicetree bindings for mux-controllers and gpio-mux
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, linux-i2c, devicetree,
linux-iio, linux-doc, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel
In-Reply-To: <1493022995-16917-1-git-send-email-peda@axentia.se>
Allow specifying that a single multiplexer controller can be used to
control several parallel multiplexers, thus enabling sharing of the
multiplexer controller by different consumers.
Add a binding for a first mux controller in the form of a GPIO based mux
controller.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
Documentation/devicetree/bindings/mux/gpio-mux.txt | 69 +++++++++
.../devicetree/bindings/mux/mux-controller.txt | 157 +++++++++++++++++++++
MAINTAINERS | 6 +
include/dt-bindings/mux/mux.h | 16 +++
4 files changed, 248 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mux/gpio-mux.txt
create mode 100644 Documentation/devicetree/bindings/mux/mux-controller.txt
create mode 100644 include/dt-bindings/mux/mux.h
diff --git a/Documentation/devicetree/bindings/mux/gpio-mux.txt b/Documentation/devicetree/bindings/mux/gpio-mux.txt
new file mode 100644
index 000000000000..b8f746344d80
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/gpio-mux.txt
@@ -0,0 +1,69 @@
+GPIO-based multiplexer controller bindings
+
+Define what GPIO pins are used to control a multiplexer. Or several
+multiplexers, if the same pins control more than one multiplexer.
+
+Required properties:
+- compatible : "gpio-mux"
+- mux-gpios : list of gpios used to control the multiplexer, least
+ significant bit first.
+- #mux-control-cells : <0>
+* Standard mux-controller bindings as decribed in mux-controller.txt
+
+Optional properties:
+- idle-state : if present, the state the mux will have when idle. The
+ special state MUX_IDLE_AS_IS is the default.
+
+The multiplexer state is defined as the number represented by the
+multiplexer GPIO pins, where the first pin is the least significant
+bit. An active pin is a binary 1, an inactive pin is a binary 0.
+
+Example:
+
+ mux: mux-controller {
+ compatible = "gpio-mux";
+ #mux-control-cells = <0>;
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+ <&pioA 1 GPIO_ACTIVE_HIGH>;
+ };
+
+ adc-mux {
+ compatible = "io-channel-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ mux-controls = <&mux>;
+
+ channels = "sync-1", "in", "out", "sync-2";
+ };
+
+ i2c-mux {
+ compatible = "i2c-mux";
+ i2c-parent = <&i2c1>;
+
+ mux-controls = <&mux>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c@0 {
+ reg = <0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ ssd1307: oled@3c {
+ /* ... */
+ };
+ };
+
+ i2c@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ pca9555: pca9555@20 {
+ /* ... */
+ };
+ };
+ };
diff --git a/Documentation/devicetree/bindings/mux/mux-controller.txt b/Documentation/devicetree/bindings/mux/mux-controller.txt
new file mode 100644
index 000000000000..4f47e4bd2fa0
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/mux-controller.txt
@@ -0,0 +1,157 @@
+Common multiplexer controller bindings
+======================================
+
+A multiplexer (or mux) controller will have one, or several, consumer devices
+that uses the mux controller. Thus, a mux controller can possibly control
+several parallel multiplexers. Presumably there will be at least one
+multiplexer needed by each consumer, but a single mux controller can of course
+control several multiplexers for a single consumer.
+
+A mux controller provides a number of states to its consumers, and the state
+space is a simple zero-based enumeration. I.e. 0-1 for a 2-way multiplexer,
+0-7 for an 8-way multiplexer, etc.
+
+
+Consumers
+---------
+
+Mux controller consumers should specify a list of mux controllers that they
+want to use with a property containing a 'mux-ctrl-list':
+
+ mux-ctrl-list ::= <single-mux-ctrl> [mux-ctrl-list]
+ single-mux-ctrl ::= <mux-ctrl-phandle> [mux-ctrl-specifier]
+ mux-ctrl-phandle : phandle to mux controller node
+ mux-ctrl-specifier : array of #mux-control-cells specifying the
+ given mux controller (controller specific)
+
+Mux controller properties should be named "mux-controls". The exact meaning of
+each mux controller property must be documented in the device tree binding for
+each consumer. An optional property "mux-control-names" may contain a list of
+strings to label each of the mux controllers listed in the "mux-controls"
+property.
+
+Drivers for devices that use more than a single mux controller can use the
+"mux-control-names" property to map the name of the requested mux controller
+to an index into the list given by the "mux-controls" property.
+
+mux-ctrl-specifier typically encodes the chip-relative mux controller number.
+If the mux controller chip only provides a single mux controller, the
+mux-ctrl-specifier can typically be left out.
+
+Example:
+
+ /* One consumer of a 2-way mux controller (one GPIO-line) */
+ mux: mux-controller {
+ compatible = "gpio-mux";
+ #mux-control-cells = <0>;
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>;
+ };
+
+ adc-mux {
+ compatible = "io-channel-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ mux-controls = <&mux>;
+ mux-control-names = "adc";
+
+ channels = "sync", "in";
+ };
+
+Note that in the example above, specifying the "mux-control-names" is redundant
+because there is only one mux controller in the list. However, if the driver
+for the consumer node in fact asks for a named mux controller, that name is of
+course still required.
+
+ /*
+ * Two consumers (one for an ADC line and one for an i2c bus) of
+ * parallel 4-way multiplexers controlled by the same two GPIO-lines.
+ */
+ mux: mux-controller {
+ compatible = "gpio-mux";
+ #mux-control-cells = <0>;
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+ <&pioA 1 GPIO_ACTIVE_HIGH>;
+ };
+
+ adc-mux {
+ compatible = "io-channel-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ mux-controls = <&mux>;
+
+ channels = "sync-1", "in", "out", "sync-2";
+ };
+
+ i2c-mux {
+ compatible = "i2c-mux";
+ i2c-parent = <&i2c1>;
+
+ mux-controls = <&mux>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c@0 {
+ reg = <0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ ssd1307: oled@3c {
+ /* ... */
+ };
+ };
+
+ i2c@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ pca9555: pca9555@20 {
+ /* ... */
+ };
+ };
+ };
+
+
+Mux controller nodes
+--------------------
+
+Mux controller nodes must specify the number of cells used for the
+specifier using the '#mux-control-cells' property.
+
+Optionally, mux controller nodes can also specify the state the mux should
+have when it is idle. The idle-state property is used for this. If the
+idle-state is not present, the mux controller is typically left as is when
+it is idle. For multiplexer chips that expose several mux controllers, the
+idle-state property is an array with one idle state for each mux controller.
+
+The special value (-1) may be used to indicate that the mux should be left
+as is when it is idle. This is the default, but can still be useful for
+mux controller chips with more than one mux controller, particularly when
+there is a need to "step past" a mux controller and set some other idle
+state for a mux controller with a higher index.
+
+Some mux controllers have the ability to disconnect the input/output of the
+multiplexer. Using this disconnected high-impedance state as the idle state
+is indicated with idle state (-2).
+
+These constants are available in
+
+ #include <dt-bindings/mux/mux.h>
+
+as MUX_IDLE_AS_IS (-1) and MUX_IDLE_DISCONNECT (-2).
+
+An example mux controller node look like this (the adg972a chip is a triple
+4-way multiplexer):
+
+ mux: mux-controller@50 {
+ compatible = "adi,adg792a";
+ reg = <0x50>;
+ #mux-control-cells = <1>;
+
+ idle-state = <MUX_IDLE_DISCONNECT MUX_IDLE_AS_IS 2>;
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index c265a5fe4848..7fc06739c8ad 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8558,6 +8558,12 @@ S: Orphan
F: drivers/mmc/host/mmc_spi.c
F: include/linux/spi/mmc_spi.h
+MULTIPLEXER SUBSYSTEM
+M: Peter Rosin <peda@axentia.se>
+S: Maintained
+F: Documentation/devicetree/bindings/mux/
+F: include/linux/dt-bindings/mux/
+
MULTISOUND SOUND DRIVER
M: Andrew Veliath <andrewtv@usa.net>
S: Maintained
diff --git a/include/dt-bindings/mux/mux.h b/include/dt-bindings/mux/mux.h
new file mode 100644
index 000000000000..c8e855c4a609
--- /dev/null
+++ b/include/dt-bindings/mux/mux.h
@@ -0,0 +1,16 @@
+/*
+ * This header provides constants for most Multiplexer bindings.
+ *
+ * Most Multiplexer bindings specify an idle state. In most cases, the
+ * the multiplexer can be left as is when idle, and in some cases it can
+ * disconnect the input/output and leave the multiplexer in a high
+ * impedance state.
+ */
+
+#ifndef _DT_BINDINGS_MUX_MUX_H
+#define _DT_BINDINGS_MUX_MUX_H
+
+#define MUX_IDLE_AS_IS (-1)
+#define MUX_IDLE_DISCONNECT (-2)
+
+#endif
--
2.1.4
^ permalink raw reply related
* [PATCH v14 03/11] mux: minimal mux subsystem
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, linux-i2c, devicetree,
linux-iio, linux-doc, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel
In-Reply-To: <1493022995-16917-1-git-send-email-peda@axentia.se>
Add a new minimalistic subsystem that handles multiplexer controllers.
When multiplexers are used in various places in the kernel, and the
same multiplexer controller can be used for several independent things,
there should be one place to implement support for said multiplexer
controller.
A single multiplexer controller can also be used to control several
parallel multiplexers, that are in turn used by different subsystems
in the kernel, leading to a need to coordinate multiplexer accesses.
The multiplexer subsystem handles this coordination.
Thanks go out to Lars-Peter Clausen, Jonathan Cameron, Rob Herring,
Wolfram Sang, Paul Gortmaker, Dan Carpenter, Colin Ian King, Greg
Kroah-Hartman and last but certainly not least to Philipp Zabel for
helpful comments, reviews, patches and general encouragement!
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
Documentation/ABI/testing/sysfs-class-mux | 16 +
Documentation/driver-model/devres.txt | 8 +
MAINTAINERS | 3 +
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/mux/Kconfig | 16 +
drivers/mux/Makefile | 5 +
drivers/mux/mux-core.c | 593 ++++++++++++++++++++++++++++++
include/linux/mux/consumer.h | 33 ++
include/linux/mux/driver.h | 111 ++++++
10 files changed, 788 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-class-mux
create mode 100644 drivers/mux/Kconfig
create mode 100644 drivers/mux/Makefile
create mode 100644 drivers/mux/mux-core.c
create mode 100644 include/linux/mux/consumer.h
create mode 100644 include/linux/mux/driver.h
diff --git a/Documentation/ABI/testing/sysfs-class-mux b/Documentation/ABI/testing/sysfs-class-mux
new file mode 100644
index 000000000000..8715f9c7bd4f
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-mux
@@ -0,0 +1,16 @@
+What: /sys/class/mux/
+Date: April 2017
+KernelVersion: 4.13
+Contact: Peter Rosin <peda@axentia.se>
+Description:
+ The mux/ class sub-directory belongs to the Generic MUX
+ Framework and provides a sysfs interface for using MUX
+ controllers.
+
+What: /sys/class/mux/muxchipN/
+Date: April 2017
+KernelVersion: 4.13
+Contact: Peter Rosin <peda@axentia.se>
+Description:
+ A /sys/class/mux/muxchipN directory is created for each
+ probed MUX chip where N is a simple enumeration.
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index efb8200819d6..e2343d9cbec7 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -337,6 +337,14 @@ MEM
MFD
devm_mfd_add_devices()
+MUX
+ devm_mux_chip_alloc()
+ devm_mux_chip_free()
+ devm_mux_chip_register()
+ devm_mux_chip_unregister()
+ devm_mux_control_get()
+ devm_mux_control_put()
+
PER-CPU MEM
devm_alloc_percpu()
devm_free_percpu()
diff --git a/MAINTAINERS b/MAINTAINERS
index 7fc06739c8ad..4cfa080878e2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8561,8 +8561,11 @@ F: include/linux/spi/mmc_spi.h
MULTIPLEXER SUBSYSTEM
M: Peter Rosin <peda@axentia.se>
S: Maintained
+F: Documentation/ABI/testing/mux/sysfs-class-mux*
F: Documentation/devicetree/bindings/mux/
F: include/linux/dt-bindings/mux/
+F: include/linux/mux/
+F: drivers/mux/
MULTISOUND SOUND DRIVER
M: Andrew Veliath <andrewtv@usa.net>
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 117ca14ccf85..a7ea13e1b869 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -204,4 +204,6 @@ source "drivers/fpga/Kconfig"
source "drivers/fsi/Kconfig"
+source "drivers/mux/Kconfig"
+
endmenu
diff --git a/drivers/Makefile b/drivers/Makefile
index 2eced9afba53..c0436f6dd5a9 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -177,3 +177,4 @@ obj-$(CONFIG_ANDROID) += android/
obj-$(CONFIG_NVMEM) += nvmem/
obj-$(CONFIG_FPGA) += fpga/
obj-$(CONFIG_FSI) += fsi/
+obj-$(CONFIG_MULTIPLEXER) += mux/
diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
new file mode 100644
index 000000000000..23ab2cde83b1
--- /dev/null
+++ b/drivers/mux/Kconfig
@@ -0,0 +1,16 @@
+#
+# Multiplexer devices
+#
+
+menuconfig MULTIPLEXER
+ tristate "Multiplexer subsystem"
+ help
+ Multiplexer controller subsystem. Multiplexers are used in a
+ variety of settings, and this subsystem abstracts their use
+ so that the rest of the kernel sees a common interface. When
+ multiple parallel multiplexers are controlled by one single
+ multiplexer controller, this subsystem also coordinates the
+ multiplexer accesses.
+
+ To compile the subsystem as a module, choose M here: the module will
+ be called mux-core.
diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile
new file mode 100644
index 000000000000..09f0299e109d
--- /dev/null
+++ b/drivers/mux/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for multiplexer devices.
+#
+
+obj-$(CONFIG_MULTIPLEXER) += mux-core.o
diff --git a/drivers/mux/mux-core.c b/drivers/mux/mux-core.c
new file mode 100644
index 000000000000..c02fa4dd2d09
--- /dev/null
+++ b/drivers/mux/mux-core.c
@@ -0,0 +1,593 @@
+/*
+ * Multiplexer subsystem
+ *
+ * Copyright (C) 2017 Axentia Technologies AB
+ *
+ * Author: Peter Rosin <peda@axentia.se>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#define pr_fmt(fmt) "mux-core: " fmt
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/idr.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mux/consumer.h>
+#include <linux/mux/driver.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+
+/*
+ * The idle-as-is "state" is not an actual state that may be selected, it
+ * only implies that the state should not be changed. So, use that state
+ * as indication that the cached state of the multiplexer is unknown.
+ */
+#define MUX_CACHE_UNKNOWN MUX_IDLE_AS_IS
+
+static struct class mux_class = {
+ .name = "mux",
+ .owner = THIS_MODULE,
+};
+
+static DEFINE_IDA(mux_ida);
+
+static int __init mux_init(void)
+{
+ ida_init(&mux_ida);
+ return class_register(&mux_class);
+}
+
+static void __exit mux_exit(void)
+{
+ class_register(&mux_class);
+ ida_destroy(&mux_ida);
+}
+
+static void mux_chip_release(struct device *dev)
+{
+ struct mux_chip *mux_chip = to_mux_chip(dev);
+
+ ida_simple_remove(&mux_ida, mux_chip->id);
+ kfree(mux_chip);
+}
+
+static struct device_type mux_type = {
+ .name = "mux-chip",
+ .release = mux_chip_release,
+};
+
+/**
+ * mux_chip_alloc() - Allocate a mux-chip.
+ * @dev: The parent device implementing the mux interface.
+ * @controllers: The number of mux controllers to allocate for this chip.
+ * @sizeof_priv: Size of extra memory area for private use by the caller.
+ *
+ * After allocating the mux-chip with the desired number of mux controllers
+ * but before registering the chip, the mux driver is required to configure
+ * the number of valid mux states in the mux_chip->mux[N].states members and
+ * the desired idle state in the returned mux_chip->mux[N].idle_state members.
+ * The default idle state is MUX_IDLE_AS_IS. The mux driver also needs to
+ * provide a pointer to the operations struct in the mux_chip->ops member
+ * before registering the mux-chip with mux_chip_register.
+ *
+ * Return: A pointer to the new mux-chip, or an ERR_PTR with a negative errno.
+ */
+struct mux_chip *mux_chip_alloc(struct device *dev,
+ unsigned int controllers, size_t sizeof_priv)
+{
+ struct mux_chip *mux_chip;
+ int i;
+
+ if (WARN_ON(!dev || !controllers))
+ return ERR_PTR(-EINVAL);
+
+ mux_chip = kzalloc(sizeof(*mux_chip) +
+ controllers * sizeof(*mux_chip->mux) +
+ sizeof_priv, GFP_KERNEL);
+ if (!mux_chip)
+ return ERR_PTR(-ENOMEM);
+
+ mux_chip->mux = (struct mux_control *)(mux_chip + 1);
+ mux_chip->dev.class = &mux_class;
+ mux_chip->dev.type = &mux_type;
+ mux_chip->dev.parent = dev;
+ mux_chip->dev.of_node = dev->of_node;
+ dev_set_drvdata(&mux_chip->dev, mux_chip);
+
+ mux_chip->id = ida_simple_get(&mux_ida, 0, 0, GFP_KERNEL);
+ if (mux_chip->id < 0) {
+ int err = mux_chip->id;
+
+ pr_err("muxchipX failed to get a device id\n");
+ kfree(mux_chip);
+ return ERR_PTR(err);
+ }
+ dev_set_name(&mux_chip->dev, "muxchip%d", mux_chip->id);
+
+ mux_chip->controllers = controllers;
+ for (i = 0; i < controllers; ++i) {
+ struct mux_control *mux = &mux_chip->mux[i];
+
+ mux->chip = mux_chip;
+ mutex_init(&mux->lock);
+ mux->cached_state = MUX_CACHE_UNKNOWN;
+ mux->idle_state = MUX_IDLE_AS_IS;
+ }
+
+ device_initialize(&mux_chip->dev);
+
+ return mux_chip;
+}
+EXPORT_SYMBOL_GPL(mux_chip_alloc);
+
+static int mux_control_set(struct mux_control *mux, int state)
+{
+ int ret = mux->chip->ops->set(mux, state);
+
+ mux->cached_state = ret < 0 ? MUX_CACHE_UNKNOWN : state;
+
+ return ret;
+}
+
+/**
+ * mux_chip_register() - Register a mux-chip, thus readying the controllers
+ * for use.
+ * @mux_chip: The mux-chip to register.
+ *
+ * Do not retry registration of the same mux-chip on failure. You should
+ * instead put it away with mux_chip_free() and allocate a new one, if you
+ * for some reason would like to retry registration.
+ *
+ * Return: Zero on success or a negative errno on error.
+ */
+int mux_chip_register(struct mux_chip *mux_chip)
+{
+ int i;
+ int ret;
+
+ for (i = 0; i < mux_chip->controllers; ++i) {
+ struct mux_control *mux = &mux_chip->mux[i];
+
+ if (mux->idle_state == mux->cached_state)
+ continue;
+
+ ret = mux_control_set(mux, mux->idle_state);
+ if (ret < 0) {
+ dev_err(&mux_chip->dev, "unable to set idle state\n");
+ return ret;
+ }
+ }
+
+ ret = device_add(&mux_chip->dev);
+ if (ret < 0)
+ dev_err(&mux_chip->dev,
+ "device_add failed in %s: %d\n", __func__, ret);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mux_chip_register);
+
+/**
+ * mux_chip_unregister() - Take the mux-chip off-line.
+ * @mux_chip: The mux-chip to unregister.
+ *
+ * mux_chip_unregister() reverses the effects of mux_chip_register().
+ * But not completely, you should not try to call mux_chip_register()
+ * on a mux-chip that has been registered before.
+ */
+void mux_chip_unregister(struct mux_chip *mux_chip)
+{
+ device_del(&mux_chip->dev);
+}
+EXPORT_SYMBOL_GPL(mux_chip_unregister);
+
+/**
+ * mux_chip_free() - Free the mux-chip for good.
+ * @mux_chip: The mux-chip to free.
+ *
+ * mux_chip_free() reverses the effects of mux_chip_alloc().
+ */
+void mux_chip_free(struct mux_chip *mux_chip)
+{
+ if (!mux_chip)
+ return;
+
+ put_device(&mux_chip->dev);
+}
+EXPORT_SYMBOL_GPL(mux_chip_free);
+
+static void devm_mux_chip_release(struct device *dev, void *res)
+{
+ struct mux_chip *mux_chip = *(struct mux_chip **)res;
+
+ mux_chip_free(mux_chip);
+}
+
+/**
+ * devm_mux_chip_alloc() - Resource-managed version of mux_chip_alloc().
+ * @dev: The parent device implementing the mux interface.
+ * @controllers: The number of mux controllers to allocate for this chip.
+ * @sizeof_priv: Size of extra memory area for private use by the caller.
+ *
+ * See mux_chip_alloc() for more details.
+ *
+ * Return: A pointer to the new mux-chip, or an ERR_PTR with a negative errno.
+ */
+struct mux_chip *devm_mux_chip_alloc(struct device *dev,
+ unsigned int controllers,
+ size_t sizeof_priv)
+{
+ struct mux_chip **ptr, *mux_chip;
+
+ ptr = devres_alloc(devm_mux_chip_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ mux_chip = mux_chip_alloc(dev, controllers, sizeof_priv);
+ if (IS_ERR(mux_chip)) {
+ devres_free(ptr);
+ return mux_chip;
+ }
+
+ *ptr = mux_chip;
+ devres_add(dev, ptr);
+
+ return mux_chip;
+}
+EXPORT_SYMBOL_GPL(devm_mux_chip_alloc);
+
+static int devm_mux_chip_match(struct device *dev, void *res, void *data)
+{
+ struct mux_chip **r = res;
+
+ return *r == data;
+}
+
+/**
+ * devm_mux_chip_free() - Resource-managed version mux_chip_free().
+ * @dev: The device that originally got the mux-chip.
+ * @mux_chip: The mux-chip to free.
+ *
+ * See mux_chip_free() for more details.
+ *
+ * Note that you do not normally need to call this function.
+ */
+void devm_mux_chip_free(struct device *dev, struct mux_chip *mux_chip)
+{
+ devres_release(dev, devm_mux_chip_release,
+ devm_mux_chip_match, mux_chip);
+}
+EXPORT_SYMBOL_GPL(devm_mux_chip_free);
+
+static void devm_mux_chip_reg_release(struct device *dev, void *res)
+{
+ struct mux_chip *mux_chip = *(struct mux_chip **)res;
+
+ mux_chip_unregister(mux_chip);
+}
+
+/**
+ * devm_mux_chip_register() - Resource-managed version mux_chip_register().
+ * @dev: The parent device implementing the mux interface.
+ * @mux_chip: The mux-chip to register.
+ *
+ * See mux_chip_register() for more details.
+ *
+ * Return: Zero on success or a negative errno on error.
+ */
+int devm_mux_chip_register(struct device *dev,
+ struct mux_chip *mux_chip)
+{
+ struct mux_chip **ptr;
+ int res;
+
+ ptr = devres_alloc(devm_mux_chip_reg_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ res = mux_chip_register(mux_chip);
+ if (res) {
+ devres_free(ptr);
+ return res;
+ }
+
+ *ptr = mux_chip;
+ devres_add(dev, ptr);
+
+ return res;
+}
+EXPORT_SYMBOL_GPL(devm_mux_chip_register);
+
+/**
+ * devm_mux_chip_unregister() - Resource-managed version mux_chip_unregister().
+ * @dev: The device that originally registered the mux-chip.
+ * @mux_chip: The mux-chip to unregister.
+ *
+ * See mux_chip_unregister() for more details.
+ *
+ * Note that you do not normally need to call this function.
+ */
+void devm_mux_chip_unregister(struct device *dev, struct mux_chip *mux_chip)
+{
+ devres_release(dev, devm_mux_chip_reg_release,
+ devm_mux_chip_match, mux_chip);
+}
+EXPORT_SYMBOL_GPL(devm_mux_chip_unregister);
+
+/**
+ * mux_control_states() - Query the number of multiplexer states.
+ * @mux: The mux-control to query.
+ *
+ * Return: The number of multiplexer states.
+ */
+unsigned int mux_control_states(struct mux_control *mux)
+{
+ return mux->states;
+}
+EXPORT_SYMBOL_GPL(mux_control_states);
+
+/*
+ * The mux->lock must be held when calling this function.
+ */
+static int __mux_control_select(struct mux_control *mux, int state)
+{
+ int ret;
+
+ if (WARN_ON(state < 0 || state >= mux->states))
+ return -EINVAL;
+
+ if (mux->cached_state == state)
+ return 0;
+
+ ret = mux_control_set(mux, state);
+ if (ret >= 0)
+ return 0;
+
+ /* The mux update failed, try to revert if appropriate... */
+ if (mux->idle_state != MUX_IDLE_AS_IS)
+ mux_control_set(mux, mux->idle_state);
+
+ return ret;
+}
+
+/**
+ * mux_control_select() - Select the given multiplexer state.
+ * @mux: The mux-control to request a change of state from.
+ * @state: The new requested state.
+ *
+ * Make sure to call mux_control_deselect() when the operation is complete and
+ * the mux-control is free for others to use, but do not call
+ * mux_control_deselect() if mux_control_select() fails.
+ *
+ * Return: 0 when the mux-control state has the requested state or a negative
+ * errno on error.
+ */
+int mux_control_select(struct mux_control *mux, unsigned int state)
+{
+ int ret;
+
+ mutex_lock(&mux->lock);
+
+ ret = __mux_control_select(mux, state);
+
+ if (ret < 0)
+ mutex_unlock(&mux->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mux_control_select);
+
+/**
+ * mux_control_try_select() - Try to select the given multiplexer state.
+ * @mux: The mux-control to request a change of state from.
+ * @state: The new requested state.
+ *
+ * Make sure to call mux_control_deselect() when the operation is complete and
+ * the mux-control is free for others to use, but do not call
+ * mux_control_deselect() if mux_control_try_select() fails.
+ *
+ * Return: 0 when the mux-control state has the requested state or a negative
+ * errno on error. Specifically -EBUSY if the mux-control is contended.
+ */
+int mux_control_try_select(struct mux_control *mux, unsigned int state)
+{
+ int ret;
+
+ if (!mutex_trylock(&mux->lock))
+ return -EBUSY;
+
+ ret = __mux_control_select(mux, state);
+
+ if (ret < 0)
+ mutex_unlock(&mux->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mux_control_try_select);
+
+/**
+ * mux_control_deselect() - Deselect the previously selected multiplexer state.
+ * @mux: The mux-control to deselect.
+ *
+ * Return: 0 on success and a negative errno on error. An error can only
+ * occur if the mux has an idle state. Note that even if an error occurs, the
+ * mux-control is unlocked and is thus free for the next access.
+ */
+int mux_control_deselect(struct mux_control *mux)
+{
+ int ret = 0;
+
+ if (mux->idle_state != MUX_IDLE_AS_IS &&
+ mux->idle_state != mux->cached_state)
+ ret = mux_control_set(mux, mux->idle_state);
+
+ mutex_unlock(&mux->lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mux_control_deselect);
+
+static int of_dev_node_match(struct device *dev, const void *data)
+{
+ return dev->of_node == data;
+}
+
+static struct mux_chip *of_find_mux_chip_by_node(struct device_node *np)
+{
+ struct device *dev;
+
+ dev = class_find_device(&mux_class, NULL, np, of_dev_node_match);
+
+ return dev ? to_mux_chip(dev) : NULL;
+}
+
+/**
+ * mux_control_get() - Get the mux-control for a device.
+ * @dev: The device that needs a mux-control.
+ * @mux_name: The name identifying the mux-control.
+ *
+ * Return: A pointer to the mux-control, or an ERR_PTR with a negative errno.
+ */
+struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
+{
+ struct device_node *np = dev->of_node;
+ struct of_phandle_args args;
+ struct mux_chip *mux_chip;
+ unsigned int controller;
+ int index = 0;
+ int ret;
+
+ if (mux_name) {
+ index = of_property_match_string(np, "mux-control-names",
+ mux_name);
+ if (index < 0) {
+ dev_err(dev, "mux controller '%s' not found\n",
+ mux_name);
+ return ERR_PTR(index);
+ }
+ }
+
+ ret = of_parse_phandle_with_args(np,
+ "mux-controls", "#mux-control-cells",
+ index, &args);
+ if (ret) {
+ dev_err(dev, "%s: failed to get mux-control %s(%i)\n",
+ np->full_name, mux_name ?: "", index);
+ return ERR_PTR(ret);
+ }
+
+ mux_chip = of_find_mux_chip_by_node(args.np);
+ of_node_put(args.np);
+ if (!mux_chip)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ if (args.args_count > 1 ||
+ (!args.args_count && (mux_chip->controllers > 1))) {
+ dev_err(dev, "%s: wrong #mux-control-cells for %s\n",
+ np->full_name, args.np->full_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ controller = 0;
+ if (args.args_count)
+ controller = args.args[0];
+
+ if (controller >= mux_chip->controllers) {
+ dev_err(dev, "%s: bad mux controller %u specified in %s\n",
+ np->full_name, controller, args.np->full_name);
+ return ERR_PTR(-EINVAL);
+ }
+
+ get_device(&mux_chip->dev);
+ return &mux_chip->mux[controller];
+}
+EXPORT_SYMBOL_GPL(mux_control_get);
+
+/**
+ * mux_control_put() - Put away the mux-control for good.
+ * @mux: The mux-control to put away.
+ *
+ * mux_control_put() reverses the effects of mux_control_get().
+ */
+void mux_control_put(struct mux_control *mux)
+{
+ put_device(&mux->chip->dev);
+}
+EXPORT_SYMBOL_GPL(mux_control_put);
+
+static void devm_mux_control_release(struct device *dev, void *res)
+{
+ struct mux_control *mux = *(struct mux_control **)res;
+
+ mux_control_put(mux);
+}
+
+/**
+ * devm_mux_control_get() - Get the mux-control for a device, with resource
+ * management.
+ * @dev: The device that needs a mux-control.
+ * @mux_name: The name identifying the mux-control.
+ *
+ * Return: Pointer to the mux-control, or an ERR_PTR with a negative errno.
+ */
+struct mux_control *devm_mux_control_get(struct device *dev,
+ const char *mux_name)
+{
+ struct mux_control **ptr, *mux;
+
+ ptr = devres_alloc(devm_mux_control_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ mux = mux_control_get(dev, mux_name);
+ if (IS_ERR(mux)) {
+ devres_free(ptr);
+ return mux;
+ }
+
+ *ptr = mux;
+ devres_add(dev, ptr);
+
+ return mux;
+}
+EXPORT_SYMBOL_GPL(devm_mux_control_get);
+
+static int devm_mux_control_match(struct device *dev, void *res, void *data)
+{
+ struct mux_control **r = res;
+
+ return *r == data;
+}
+
+/**
+ * devm_mux_control_put() - Resource-managed version mux_control_put().
+ * @dev: The device that originally got the mux-control.
+ * @mux: The mux-control to put away.
+ *
+ * Note that you do not normally need to call this function.
+ */
+void devm_mux_control_put(struct device *dev, struct mux_control *mux)
+{
+ devres_release(dev, devm_mux_control_release,
+ devm_mux_control_match, mux);
+}
+EXPORT_SYMBOL_GPL(devm_mux_control_put);
+
+/*
+ * Using subsys_initcall instead of module_init here to try to ensure - for
+ * the non-modular case - that the subsystem is initialized when mux consumers
+ * and mux controllers start to use it.
+ * For the modular case, the ordering is ensured with module dependencies.
+ */
+subsys_initcall(mux_init);
+module_exit(mux_exit);
+
+MODULE_DESCRIPTION("Multiplexer subsystem");
+MODULE_AUTHOR("Peter Rosin <peda@axentia.se>");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mux/consumer.h b/include/linux/mux/consumer.h
new file mode 100644
index 000000000000..a2a61834bd3a
--- /dev/null
+++ b/include/linux/mux/consumer.h
@@ -0,0 +1,33 @@
+/*
+ * mux/consumer.h - definitions for the multiplexer consumer interface
+ *
+ * Copyright (C) 2017 Axentia Technologies AB
+ *
+ * Author: Peter Rosin <peda@axentia.se>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _LINUX_MUX_CONSUMER_H
+#define _LINUX_MUX_CONSUMER_H
+
+struct device;
+struct mux_control;
+
+unsigned int mux_control_states(struct mux_control *mux);
+int __must_check mux_control_select(struct mux_control *mux,
+ unsigned int state);
+int __must_check mux_control_try_select(struct mux_control *mux,
+ unsigned int state);
+int mux_control_deselect(struct mux_control *mux);
+
+struct mux_control *mux_control_get(struct device *dev, const char *mux_name);
+void mux_control_put(struct mux_control *mux);
+
+struct mux_control *devm_mux_control_get(struct device *dev,
+ const char *mux_name);
+void devm_mux_control_put(struct device *dev, struct mux_control *mux);
+
+#endif /* _LINUX_MUX_CONSUMER_H */
diff --git a/include/linux/mux/driver.h b/include/linux/mux/driver.h
new file mode 100644
index 000000000000..95269f40670a
--- /dev/null
+++ b/include/linux/mux/driver.h
@@ -0,0 +1,111 @@
+/*
+ * mux/driver.h - definitions for the multiplexer driver interface
+ *
+ * Copyright (C) 2017 Axentia Technologies AB
+ *
+ * Author: Peter Rosin <peda@axentia.se>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _LINUX_MUX_DRIVER_H
+#define _LINUX_MUX_DRIVER_H
+
+#include <dt-bindings/mux/mux.h>
+#include <linux/device.h>
+#include <linux/mutex.h>
+#include <linux/semaphore.h>
+
+struct mux_chip;
+struct mux_control;
+
+/**
+ * struct mux_control_ops - Mux controller operations for a mux chip.
+ * @set: Set the state of the given mux controller.
+ */
+struct mux_control_ops {
+ int (*set)(struct mux_control *mux, int state);
+};
+
+/**
+ * struct mux_control - Represents a mux controller.
+ * @lock: Protects the mux controller state.
+ * @chip: The mux chip that is handling this mux controller.
+ * @cached_state: The current mux controller state, or -1 if none.
+ * @states: The number of mux controller states.
+ * @idle_state: The mux controller state to use when inactive, or one
+ * of MUX_IDLE_AS_IS and MUX_IDLE_DISCONNECT.
+ *
+ * Mux drivers may only change @states and @idle_state, and may only do so
+ * between allocation and registration of the mux controller. Specifically,
+ * @cached_state is internal to the mux core and should never be written by
+ * mux drivers.
+ */
+struct mux_control {
+ struct mutex lock; /* protects the state of the mux */
+
+ struct mux_chip *chip;
+ int cached_state;
+
+ unsigned int states;
+ int idle_state;
+};
+
+/**
+ * struct mux_chip - Represents a chip holding mux controllers.
+ * @controllers: Number of mux controllers handled by the chip.
+ * @mux: Array of mux controllers that are handled.
+ * @dev: Device structure.
+ * @id: Used to identify the device internally.
+ * @ops: Mux controller operations.
+ */
+struct mux_chip {
+ unsigned int controllers;
+ struct mux_control *mux;
+ struct device dev;
+ int id;
+
+ const struct mux_control_ops *ops;
+};
+
+#define to_mux_chip(x) container_of((x), struct mux_chip, dev)
+
+/**
+ * mux_chip_priv() - Get the extra memory reserved by mux_chip_alloc().
+ * @mux_chip: The mux-chip to get the private memory from.
+ *
+ * Return: Pointer to the private memory reserved by the allocator.
+ */
+static inline void *mux_chip_priv(struct mux_chip *mux_chip)
+{
+ return &mux_chip->mux[mux_chip->controllers];
+}
+
+struct mux_chip *mux_chip_alloc(struct device *dev,
+ unsigned int controllers, size_t sizeof_priv);
+int mux_chip_register(struct mux_chip *mux_chip);
+void mux_chip_unregister(struct mux_chip *mux_chip);
+void mux_chip_free(struct mux_chip *mux_chip);
+
+struct mux_chip *devm_mux_chip_alloc(struct device *dev,
+ unsigned int controllers,
+ size_t sizeof_priv);
+int devm_mux_chip_register(struct device *dev, struct mux_chip *mux_chip);
+void devm_mux_chip_unregister(struct device *dev, struct mux_chip *mux_chip);
+void devm_mux_chip_free(struct device *dev, struct mux_chip *mux_chip);
+
+/**
+ * mux_control_get_index() - Get the index of the given mux controller
+ * @mux: The mux-control to get the index for.
+ *
+ * Return: The index of the mux controller within the mux chip the mux
+ * controller is a part of.
+ */
+static inline unsigned int mux_control_get_index(struct mux_control *mux)
+{
+ return mux - mux->chip->mux;
+}
+
+#endif /* _LINUX_MUX_DRIVER_H */
--
2.1.4
^ permalink raw reply related
* [PATCH v14 04/11] mux: gpio: add mux controller driver for gpio based multiplexers
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel-u79uwXL29TY76Z2rM5mHXA, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet,
linux-i2c-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
linux-doc-u79uwXL29TY76Z2rM5mHXA, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel-bIcnvbaLZ9MEGnE8C9+IrQ
In-Reply-To: <1493022995-16917-1-git-send-email-peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
The driver builds a single multiplexer controller using a number
of gpio pins. For N pins, there will be 2^N possible multiplexer
states. The GPIO pins can be connected (by the hardware) to several
multiplexers, which in that case will be operated in parallel.
Reviewed-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Signed-off-by: Peter Rosin <peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
---
drivers/mux/Kconfig | 18 ++++++++
drivers/mux/Makefile | 1 +
drivers/mux/mux-gpio.c | 114 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 133 insertions(+)
create mode 100644 drivers/mux/mux-gpio.c
diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
index 23ab2cde83b1..e580c2d028d2 100644
--- a/drivers/mux/Kconfig
+++ b/drivers/mux/Kconfig
@@ -14,3 +14,21 @@ menuconfig MULTIPLEXER
To compile the subsystem as a module, choose M here: the module will
be called mux-core.
+
+if MULTIPLEXER
+
+config MUX_GPIO
+ tristate "GPIO-controlled Multiplexer"
+ depends on GPIOLIB
+ help
+ GPIO-controlled Multiplexer controller.
+
+ The driver builds a single multiplexer controller using a number
+ of gpio pins. For N pins, there will be 2^N possible multiplexer
+ states. The GPIO pins can be connected (by the hardware) to several
+ multiplexers, which in that case will be operated in parallel.
+
+ To compile the driver as a module, choose M here: the module will
+ be called mux-gpio.
+
+endif
diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile
index 09f0299e109d..bb16953f6290 100644
--- a/drivers/mux/Makefile
+++ b/drivers/mux/Makefile
@@ -3,3 +3,4 @@
#
obj-$(CONFIG_MULTIPLEXER) += mux-core.o
+obj-$(CONFIG_MUX_GPIO) += mux-gpio.o
diff --git a/drivers/mux/mux-gpio.c b/drivers/mux/mux-gpio.c
new file mode 100644
index 000000000000..468bf1709606
--- /dev/null
+++ b/drivers/mux/mux-gpio.c
@@ -0,0 +1,114 @@
+/*
+ * GPIO-controlled multiplexer driver
+ *
+ * Copyright (C) 2017 Axentia Technologies AB
+ *
+ * Author: Peter Rosin <peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/mux/driver.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+
+struct mux_gpio {
+ struct gpio_descs *gpios;
+ int *val;
+};
+
+static int mux_gpio_set(struct mux_control *mux, int state)
+{
+ struct mux_gpio *mux_gpio = mux_chip_priv(mux->chip);
+ int i;
+
+ for (i = 0; i < mux_gpio->gpios->ndescs; i++)
+ mux_gpio->val[i] = (state >> i) & 1;
+
+ gpiod_set_array_value_cansleep(mux_gpio->gpios->ndescs,
+ mux_gpio->gpios->desc,
+ mux_gpio->val);
+
+ return 0;
+}
+
+static const struct mux_control_ops mux_gpio_ops = {
+ .set = mux_gpio_set,
+};
+
+static const struct of_device_id mux_gpio_dt_ids[] = {
+ { .compatible = "gpio-mux", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mux_gpio_dt_ids);
+
+static int mux_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mux_chip *mux_chip;
+ struct mux_gpio *mux_gpio;
+ int pins;
+ s32 idle_state;
+ int ret;
+
+ pins = gpiod_count(dev, "mux");
+ if (pins < 0)
+ return pins;
+
+ mux_chip = devm_mux_chip_alloc(dev, 1, sizeof(*mux_gpio) +
+ pins * sizeof(*mux_gpio->val));
+ if (IS_ERR(mux_chip))
+ return PTR_ERR(mux_chip);
+
+ mux_gpio = mux_chip_priv(mux_chip);
+ mux_gpio->val = (int *)(mux_gpio + 1);
+ mux_chip->ops = &mux_gpio_ops;
+
+ mux_gpio->gpios = devm_gpiod_get_array(dev, "mux", GPIOD_OUT_LOW);
+ if (IS_ERR(mux_gpio->gpios)) {
+ ret = PTR_ERR(mux_gpio->gpios);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "failed to get gpios\n");
+ return ret;
+ }
+ WARN_ON(pins != mux_gpio->gpios->ndescs);
+ mux_chip->mux->states = 1 << pins;
+
+ ret = device_property_read_u32(dev, "idle-state", (u32 *)&idle_state);
+ if (ret >= 0 && idle_state != MUX_IDLE_AS_IS) {
+ if (idle_state < 0 || idle_state >= mux_chip->mux->states) {
+ dev_err(dev, "invalid idle-state %u\n", idle_state);
+ return -EINVAL;
+ }
+
+ mux_chip->mux->idle_state = idle_state;
+ }
+
+ ret = devm_mux_chip_register(dev, mux_chip);
+ if (ret < 0)
+ return ret;
+
+ dev_info(dev, "%u-way mux-controller registered\n",
+ mux_chip->mux->states);
+
+ return 0;
+}
+
+static struct platform_driver mux_gpio_driver = {
+ .driver = {
+ .name = "gpio-mux",
+ .of_match_table = of_match_ptr(mux_gpio_dt_ids),
+ },
+ .probe = mux_gpio_probe,
+};
+module_platform_driver(mux_gpio_driver);
+
+MODULE_DESCRIPTION("GPIO-controlled multiplexer driver");
+MODULE_AUTHOR("Peter Rosin <peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>");
+MODULE_LICENSE("GPL v2");
--
2.1.4
^ permalink raw reply related
* [PATCH v14 05/11] iio: inkern: api for manipulating ext_info of iio channels
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, linux-i2c, devicetree,
linux-iio, linux-doc, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel
In-Reply-To: <1493022995-16917-1-git-send-email-peda@axentia.se>
Extend the inkern api with functions for reading and writing ext_info
of iio channels.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/iio/inkern.c | 60 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/iio/consumer.h | 37 +++++++++++++++++++++++++++
2 files changed, 97 insertions(+)
diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index 7a13535dc3e9..8292ad4435ea 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -869,3 +869,63 @@ int iio_write_channel_raw(struct iio_channel *chan, int val)
return ret;
}
EXPORT_SYMBOL_GPL(iio_write_channel_raw);
+
+unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan)
+{
+ const struct iio_chan_spec_ext_info *ext_info;
+ unsigned int i = 0;
+
+ if (!chan->channel->ext_info)
+ return i;
+
+ for (ext_info = chan->channel->ext_info; ext_info->name; ext_info++)
+ ++i;
+
+ return i;
+}
+EXPORT_SYMBOL_GPL(iio_get_channel_ext_info_count);
+
+static const struct iio_chan_spec_ext_info *iio_lookup_ext_info(
+ const struct iio_channel *chan,
+ const char *attr)
+{
+ const struct iio_chan_spec_ext_info *ext_info;
+
+ if (!chan->channel->ext_info)
+ return NULL;
+
+ for (ext_info = chan->channel->ext_info; ext_info->name; ++ext_info) {
+ if (!strcmp(attr, ext_info->name))
+ return ext_info;
+ }
+
+ return NULL;
+}
+
+ssize_t iio_read_channel_ext_info(struct iio_channel *chan,
+ const char *attr, char *buf)
+{
+ const struct iio_chan_spec_ext_info *ext_info;
+
+ ext_info = iio_lookup_ext_info(chan, attr);
+ if (!ext_info)
+ return -EINVAL;
+
+ return ext_info->read(chan->indio_dev, ext_info->private,
+ chan->channel, buf);
+}
+EXPORT_SYMBOL_GPL(iio_read_channel_ext_info);
+
+ssize_t iio_write_channel_ext_info(struct iio_channel *chan, const char *attr,
+ const char *buf, size_t len)
+{
+ const struct iio_chan_spec_ext_info *ext_info;
+
+ ext_info = iio_lookup_ext_info(chan, attr);
+ if (!ext_info)
+ return -EINVAL;
+
+ return ext_info->write(chan->indio_dev, ext_info->private,
+ chan->channel, buf, len);
+}
+EXPORT_SYMBOL_GPL(iio_write_channel_ext_info);
diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h
index 47eeec3218b5..5e347a9805fd 100644
--- a/include/linux/iio/consumer.h
+++ b/include/linux/iio/consumer.h
@@ -312,4 +312,41 @@ int iio_read_channel_scale(struct iio_channel *chan, int *val,
int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
int *processed, unsigned int scale);
+/**
+ * iio_get_channel_ext_info_count() - get number of ext_info attributes
+ * connected to the channel.
+ * @chan: The channel being queried
+ *
+ * Returns the number of ext_info attributes
+ */
+unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan);
+
+/**
+ * iio_read_channel_ext_info() - read ext_info attribute from a given channel
+ * @chan: The channel being queried.
+ * @attr: The ext_info attribute to read.
+ * @buf: Where to store the attribute value. Assumed to hold
+ * at least PAGE_SIZE bytes.
+ *
+ * Returns the number of bytes written to buf (perhaps w/o zero termination;
+ * it need not even be a string), or an error code.
+ */
+ssize_t iio_read_channel_ext_info(struct iio_channel *chan,
+ const char *attr, char *buf);
+
+/**
+ * iio_write_channel_ext_info() - write ext_info attribute from a given channel
+ * @chan: The channel being queried.
+ * @attr: The ext_info attribute to read.
+ * @buf: The new attribute value. Strings needs to be zero-
+ * terminated, but the terminator should not be included
+ * in the below len.
+ * @len: The size of the new attribute value.
+ *
+ * Returns the number of accepted bytes, which should be the same as len.
+ * An error code can also be returned.
+ */
+ssize_t iio_write_channel_ext_info(struct iio_channel *chan, const char *attr,
+ const char *buf, size_t len);
+
#endif
--
2.1.4
^ permalink raw reply related
* [PATCH v14 06/11] dt-bindings: iio: io-channel-mux: document io-channel-mux bindings
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, linux-i2c, devicetree,
linux-iio, linux-doc, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel
In-Reply-To: <1493022995-16917-1-git-send-email-peda@axentia.se>
Describe how a multiplexer can be used to select which signal is fed to
an io-channel.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
.../bindings/iio/multiplexer/io-channel-mux.txt | 39 ++++++++++++++++++++++
MAINTAINERS | 6 ++++
2 files changed, 45 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt
diff --git a/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt b/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt
new file mode 100644
index 000000000000..c82794002595
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt
@@ -0,0 +1,39 @@
+I/O channel multiplexer bindings
+
+If a multiplexer is used to select which hardware signal is fed to
+e.g. an ADC channel, these bindings describe that situation.
+
+Required properties:
+- compatible : "io-channel-mux"
+- io-channels : Channel node of the parent channel that has multiplexed
+ input.
+- io-channel-names : Should be "parent".
+- #address-cells = <1>;
+- #size-cells = <0>;
+- mux-controls : Mux controller node to use for operating the mux
+- channels : List of strings, labeling the mux controller states.
+
+For each non-empty string in the channels property, an io-channel will
+be created. The number of this io-channel is the same as the index into
+the list of strings in the channels property, and also matches the mux
+controller state. The mux controller state is described in
+../mux/mux-controller.txt
+
+Example:
+ mux: mux-controller {
+ compatible = "mux-gpio";
+ #mux-control-cells = <0>;
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+ <&pioA 1 GPIO_ACTIVE_HIGH>;
+ };
+
+ adc-mux {
+ compatible = "io-channel-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ mux-controls = <&mux>;
+
+ channels = "sync", "in", "system-regulator";
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index 4cfa080878e2..1cde195bba25 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6360,6 +6360,12 @@ F: Documentation/ABI/testing/sysfs-bus-iio-adc-envelope-detector
F: Documentation/devicetree/bindings/iio/adc/envelope-detector.txt
F: drivers/iio/adc/envelope-detector.c
+IIO MULTIPLEXER
+M: Peter Rosin <peda@axentia.se>
+L: linux-iio@vger.kernel.org
+S: Maintained
+F: Documentation/devicetree/bindings/iio/multiplexer/iio-mux.txt
+
IIO SUBSYSTEM AND DRIVERS
M: Jonathan Cameron <jic23@kernel.org>
R: Hartmut Knaack <knaack.h@gmx.de>
--
2.1.4
^ permalink raw reply related
* [PATCH v14 07/11] iio: multiplexer: new iio category and iio-mux driver
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, linux-i2c, devicetree,
linux-iio, linux-doc, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel
In-Reply-To: <1493022995-16917-1-git-send-email-peda@axentia.se>
When a multiplexer changes how an iio device behaves (for example
by feeding different signals to an ADC), this driver can be used
to create one virtual iio channel for each multiplexer state.
Depends on the generic multiplexer subsystem.
Cache any ext_info values from the parent iio channel, creating a private
copy of the ext_info attributes for each multiplexer state/channel.
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
MAINTAINERS | 1 +
drivers/iio/Kconfig | 1 +
drivers/iio/Makefile | 1 +
drivers/iio/multiplexer/Kconfig | 18 ++
drivers/iio/multiplexer/Makefile | 6 +
drivers/iio/multiplexer/iio-mux.c | 459 ++++++++++++++++++++++++++++++++++++++
6 files changed, 486 insertions(+)
create mode 100644 drivers/iio/multiplexer/Kconfig
create mode 100644 drivers/iio/multiplexer/Makefile
create mode 100644 drivers/iio/multiplexer/iio-mux.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 1cde195bba25..519719069211 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6365,6 +6365,7 @@ M: Peter Rosin <peda@axentia.se>
L: linux-iio@vger.kernel.org
S: Maintained
F: Documentation/devicetree/bindings/iio/multiplexer/iio-mux.txt
+F: drivers/iio/multiplexer/iio-mux.c
IIO SUBSYSTEM AND DRIVERS
M: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
index a918270d6f54..b3c8c6ef0dff 100644
--- a/drivers/iio/Kconfig
+++ b/drivers/iio/Kconfig
@@ -83,6 +83,7 @@ source "drivers/iio/humidity/Kconfig"
source "drivers/iio/imu/Kconfig"
source "drivers/iio/light/Kconfig"
source "drivers/iio/magnetometer/Kconfig"
+source "drivers/iio/multiplexer/Kconfig"
source "drivers/iio/orientation/Kconfig"
if IIO_TRIGGER
source "drivers/iio/trigger/Kconfig"
diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
index 33fa4026f92c..93c769cd99bf 100644
--- a/drivers/iio/Makefile
+++ b/drivers/iio/Makefile
@@ -28,6 +28,7 @@ obj-y += humidity/
obj-y += imu/
obj-y += light/
obj-y += magnetometer/
+obj-y += multiplexer/
obj-y += orientation/
obj-y += potentiometer/
obj-y += potentiostat/
diff --git a/drivers/iio/multiplexer/Kconfig b/drivers/iio/multiplexer/Kconfig
new file mode 100644
index 000000000000..70a044510686
--- /dev/null
+++ b/drivers/iio/multiplexer/Kconfig
@@ -0,0 +1,18 @@
+#
+# Multiplexer drivers
+#
+# When adding new entries keep the list in alphabetical order
+
+menu "Multiplexers"
+
+config IIO_MUX
+ tristate "IIO multiplexer driver"
+ select MULTIPLEXER
+ depends on OF
+ help
+ Say yes here to build support for the IIO multiplexer.
+
+ To compile this driver as a module, choose M here: the
+ module will be called iio-mux.
+
+endmenu
diff --git a/drivers/iio/multiplexer/Makefile b/drivers/iio/multiplexer/Makefile
new file mode 100644
index 000000000000..68be3c4abd07
--- /dev/null
+++ b/drivers/iio/multiplexer/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for industrial I/O multiplexer drivers
+#
+
+# When adding new entries keep the list in alphabetical order
+obj-$(CONFIG_IIO_MUX) += iio-mux.o
diff --git a/drivers/iio/multiplexer/iio-mux.c b/drivers/iio/multiplexer/iio-mux.c
new file mode 100644
index 000000000000..37ba007f8dca
--- /dev/null
+++ b/drivers/iio/multiplexer/iio-mux.c
@@ -0,0 +1,459 @@
+/*
+ * IIO multiplexer driver
+ *
+ * Copyright (C) 2017 Axentia Technologies AB
+ *
+ * Author: Peter Rosin <peda@axentia.se>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/err.h>
+#include <linux/iio/consumer.h>
+#include <linux/iio/iio.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/mux/consumer.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+struct mux_ext_info_cache {
+ char *data;
+ ssize_t size;
+};
+
+struct mux_child {
+ struct mux_ext_info_cache *ext_info_cache;
+};
+
+struct mux {
+ int cached_state;
+ struct mux_control *control;
+ struct iio_channel *parent;
+ struct iio_dev *indio_dev;
+ struct iio_chan_spec *chan;
+ struct iio_chan_spec_ext_info *ext_info;
+ struct mux_child *child;
+};
+
+static int iio_mux_select(struct mux *mux, int idx)
+{
+ struct mux_child *child = &mux->child[idx];
+ struct iio_chan_spec const *chan = &mux->chan[idx];
+ int ret;
+ int i;
+
+ ret = mux_control_select(mux->control, chan->channel);
+ if (ret < 0) {
+ mux->cached_state = -1;
+ return ret;
+ }
+
+ if (mux->cached_state == chan->channel)
+ return 0;
+
+ if (chan->ext_info) {
+ for (i = 0; chan->ext_info[i].name; ++i) {
+ const char *attr = chan->ext_info[i].name;
+ struct mux_ext_info_cache *cache;
+
+ cache = &child->ext_info_cache[i];
+
+ if (cache->size < 0)
+ continue;
+
+ ret = iio_write_channel_ext_info(mux->parent, attr,
+ cache->data,
+ cache->size);
+
+ if (ret < 0) {
+ mux_control_deselect(mux->control);
+ mux->cached_state = -1;
+ return ret;
+ }
+ }
+ }
+ mux->cached_state = chan->channel;
+
+ return 0;
+}
+
+static void iio_mux_deselect(struct mux *mux)
+{
+ mux_control_deselect(mux->control);
+}
+
+static int mux_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct mux *mux = iio_priv(indio_dev);
+ int idx = chan - mux->chan;
+ int ret;
+
+ ret = iio_mux_select(mux, idx);
+ if (ret < 0)
+ return ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = iio_read_channel_raw(mux->parent, val);
+ break;
+
+ case IIO_CHAN_INFO_SCALE:
+ ret = iio_read_channel_scale(mux->parent, val, val2);
+ break;
+
+ default:
+ ret = -EINVAL;
+ }
+
+ iio_mux_deselect(mux);
+
+ return ret;
+}
+
+static int mux_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long mask)
+{
+ struct mux *mux = iio_priv(indio_dev);
+ int idx = chan - mux->chan;
+ int ret;
+
+ ret = iio_mux_select(mux, idx);
+ if (ret < 0)
+ return ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ *type = IIO_VAL_INT;
+ ret = iio_read_avail_channel_raw(mux->parent, vals, length);
+ break;
+
+ default:
+ ret = -EINVAL;
+ }
+
+ iio_mux_deselect(mux);
+
+ return ret;
+}
+
+static int mux_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct mux *mux = iio_priv(indio_dev);
+ int idx = chan - mux->chan;
+ int ret;
+
+ ret = iio_mux_select(mux, idx);
+ if (ret < 0)
+ return ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = iio_write_channel_raw(mux->parent, val);
+ break;
+
+ default:
+ ret = -EINVAL;
+ }
+
+ iio_mux_deselect(mux);
+
+ return ret;
+}
+
+static const struct iio_info mux_info = {
+ .read_raw = mux_read_raw,
+ .read_avail = mux_read_avail,
+ .write_raw = mux_write_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static ssize_t mux_read_ext_info(struct iio_dev *indio_dev, uintptr_t private,
+ struct iio_chan_spec const *chan, char *buf)
+{
+ struct mux *mux = iio_priv(indio_dev);
+ int idx = chan - mux->chan;
+ ssize_t ret;
+
+ ret = iio_mux_select(mux, idx);
+ if (ret < 0)
+ return ret;
+
+ ret = iio_read_channel_ext_info(mux->parent,
+ mux->ext_info[private].name,
+ buf);
+
+ iio_mux_deselect(mux);
+
+ return ret;
+}
+
+static ssize_t mux_write_ext_info(struct iio_dev *indio_dev, uintptr_t private,
+ struct iio_chan_spec const *chan,
+ const char *buf, size_t len)
+{
+ struct device *dev = indio_dev->dev.parent;
+ struct mux *mux = iio_priv(indio_dev);
+ int idx = chan - mux->chan;
+ char *new;
+ ssize_t ret;
+
+ if (len >= PAGE_SIZE)
+ return -EINVAL;
+
+ ret = iio_mux_select(mux, idx);
+ if (ret < 0)
+ return ret;
+
+ new = devm_kmemdup(dev, buf, len + 1, GFP_KERNEL);
+ if (!new) {
+ iio_mux_deselect(mux);
+ return -ENOMEM;
+ }
+
+ new[len] = 0;
+
+ ret = iio_write_channel_ext_info(mux->parent,
+ mux->ext_info[private].name,
+ buf, len);
+ if (ret < 0) {
+ iio_mux_deselect(mux);
+ devm_kfree(dev, new);
+ return ret;
+ }
+
+ devm_kfree(dev, mux->child[idx].ext_info_cache[private].data);
+ mux->child[idx].ext_info_cache[private].data = new;
+ mux->child[idx].ext_info_cache[private].size = len;
+
+ iio_mux_deselect(mux);
+
+ return ret;
+}
+
+static int mux_configure_channel(struct device *dev, struct mux *mux,
+ u32 state, const char *label, int idx)
+{
+ struct mux_child *child = &mux->child[idx];
+ struct iio_chan_spec *chan = &mux->chan[idx];
+ struct iio_chan_spec const *pchan = mux->parent->channel;
+ char *page = NULL;
+ int num_ext_info;
+ int i;
+ int ret;
+
+ chan->indexed = 1;
+ chan->output = pchan->output;
+ chan->datasheet_name = label;
+ chan->ext_info = mux->ext_info;
+
+ ret = iio_get_channel_type(mux->parent, &chan->type);
+ if (ret < 0) {
+ dev_err(dev, "failed to get parent channel type\n");
+ return ret;
+ }
+
+ if (iio_channel_has_info(pchan, IIO_CHAN_INFO_RAW))
+ chan->info_mask_separate |= BIT(IIO_CHAN_INFO_RAW);
+ if (iio_channel_has_info(pchan, IIO_CHAN_INFO_SCALE))
+ chan->info_mask_separate |= BIT(IIO_CHAN_INFO_SCALE);
+
+ if (iio_channel_has_available(pchan, IIO_CHAN_INFO_RAW))
+ chan->info_mask_separate_available |= BIT(IIO_CHAN_INFO_RAW);
+
+ if (state >= mux_control_states(mux->control)) {
+ dev_err(dev, "too many channels\n");
+ return -EINVAL;
+ }
+
+ chan->channel = state;
+
+ num_ext_info = iio_get_channel_ext_info_count(mux->parent);
+ if (num_ext_info) {
+ page = devm_kzalloc(dev, PAGE_SIZE, GFP_KERNEL);
+ if (!page)
+ return -ENOMEM;
+ }
+ child->ext_info_cache = devm_kzalloc(dev,
+ sizeof(*child->ext_info_cache) *
+ num_ext_info, GFP_KERNEL);
+ for (i = 0; i < num_ext_info; ++i) {
+ child->ext_info_cache[i].size = -1;
+
+ if (!pchan->ext_info[i].write)
+ continue;
+ if (!pchan->ext_info[i].read)
+ continue;
+
+ ret = iio_read_channel_ext_info(mux->parent,
+ mux->ext_info[i].name,
+ page);
+ if (ret < 0) {
+ dev_err(dev, "failed to get ext_info '%s'\n",
+ pchan->ext_info[i].name);
+ return ret;
+ }
+ if (ret >= PAGE_SIZE) {
+ dev_err(dev, "too large ext_info '%s'\n",
+ pchan->ext_info[i].name);
+ return -EINVAL;
+ }
+
+ child->ext_info_cache[i].data = devm_kmemdup(dev, page, ret + 1,
+ GFP_KERNEL);
+ child->ext_info_cache[i].data[ret] = 0;
+ child->ext_info_cache[i].size = ret;
+ }
+
+ if (page)
+ devm_kfree(dev, page);
+
+ return 0;
+}
+
+/*
+ * Same as of_property_for_each_string(), but also keeps track of the
+ * index of each string.
+ */
+#define of_property_for_each_string_index(np, propname, prop, s, i) \
+ for (prop = of_find_property(np, propname, NULL), \
+ s = of_prop_next_string(prop, NULL), \
+ i = 0; \
+ s; \
+ s = of_prop_next_string(prop, s), \
+ i++)
+
+static int mux_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = pdev->dev.of_node;
+ struct iio_dev *indio_dev;
+ struct iio_channel *parent;
+ struct mux *mux;
+ struct property *prop;
+ const char *label;
+ u32 state;
+ int sizeof_ext_info;
+ int children;
+ int sizeof_priv;
+ int i;
+ int ret;
+
+ if (!np)
+ return -ENODEV;
+
+ parent = devm_iio_channel_get(dev, "parent");
+ if (IS_ERR(parent)) {
+ if (PTR_ERR(parent) != -EPROBE_DEFER)
+ dev_err(dev, "failed to get parent channel\n");
+ return PTR_ERR(parent);
+ }
+
+ sizeof_ext_info = iio_get_channel_ext_info_count(parent);
+ if (sizeof_ext_info) {
+ sizeof_ext_info += 1; /* one extra entry for the sentinel */
+ sizeof_ext_info *= sizeof(*mux->ext_info);
+ }
+
+ children = 0;
+ of_property_for_each_string(np, "channels", prop, label) {
+ if (*label)
+ children++;
+ }
+ if (children <= 0) {
+ dev_err(dev, "not even a single child\n");
+ return -EINVAL;
+ }
+
+ sizeof_priv = sizeof(*mux);
+ sizeof_priv += sizeof(*mux->child) * children;
+ sizeof_priv += sizeof(*mux->chan) * children;
+ sizeof_priv += sizeof_ext_info;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof_priv);
+ if (!indio_dev)
+ return -ENOMEM;
+
+ mux = iio_priv(indio_dev);
+ mux->child = (struct mux_child *)(mux + 1);
+ mux->chan = (struct iio_chan_spec *)(mux->child + children);
+
+ platform_set_drvdata(pdev, indio_dev);
+
+ mux->parent = parent;
+ mux->cached_state = -1;
+
+ indio_dev->name = dev_name(dev);
+ indio_dev->dev.parent = dev;
+ indio_dev->info = &mux_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = mux->chan;
+ indio_dev->num_channels = children;
+ if (sizeof_ext_info) {
+ mux->ext_info = devm_kmemdup(dev,
+ parent->channel->ext_info,
+ sizeof_ext_info, GFP_KERNEL);
+ if (!mux->ext_info)
+ return -ENOMEM;
+
+ for (i = 0; mux->ext_info[i].name; ++i) {
+ if (parent->channel->ext_info[i].read)
+ mux->ext_info[i].read = mux_read_ext_info;
+ if (parent->channel->ext_info[i].write)
+ mux->ext_info[i].write = mux_write_ext_info;
+ mux->ext_info[i].private = i;
+ }
+ }
+
+ mux->control = devm_mux_control_get(dev, NULL);
+ if (IS_ERR(mux->control)) {
+ if (PTR_ERR(mux->control) != -EPROBE_DEFER)
+ dev_err(dev, "failed to get control-mux\n");
+ return PTR_ERR(mux->control);
+ }
+
+ i = 0;
+ of_property_for_each_string_index(np, "channels", prop, label, state) {
+ if (!*label)
+ continue;
+
+ ret = mux_configure_channel(dev, mux, state, label, i++);
+ if (ret < 0)
+ return ret;
+ }
+
+ ret = devm_iio_device_register(dev, indio_dev);
+ if (ret) {
+ dev_err(dev, "failed to register iio device\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id mux_match[] = {
+ { .compatible = "io-channel-mux" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mux_match);
+
+static struct platform_driver mux_driver = {
+ .probe = mux_probe,
+ .driver = {
+ .name = "iio-mux",
+ .of_match_table = mux_match,
+ },
+};
+module_platform_driver(mux_driver);
+
+MODULE_DESCRIPTION("IIO multiplexer driver");
+MODULE_AUTHOR("Peter Rosin <peda@axentia.se>");
+MODULE_LICENSE("GPL v2");
--
2.1.4
^ permalink raw reply related
* [PATCH v14 08/11] dt-bindings: i2c: i2c-mux: document general purpose i2c-mux bindings
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, linux-i2c, devicetree,
linux-iio, linux-doc, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel
In-Reply-To: <1493022995-16917-1-git-send-email-peda@axentia.se>
Describe how a general purpose multiplexer controller is used to mux an
i2c bus.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
.../devicetree/bindings/i2c/i2c-mux-gpmux.txt | 99 ++++++++++++++++++++++
1 file changed, 99 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
new file mode 100644
index 000000000000..2907dab56298
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-gpmux.txt
@@ -0,0 +1,99 @@
+General Purpose I2C Bus Mux
+
+This binding describes an I2C bus multiplexer that uses a mux controller
+from the mux subsystem to route the I2C signals.
+
+ .-----. .-----.
+ | dev | | dev |
+ .------------. '-----' '-----'
+ | SoC | | |
+ | | .--------+--------'
+ | .------. | .------+ child bus A, on MUX value set to 0
+ | | I2C |-|--| Mux |
+ | '------' | '--+---+ child bus B, on MUX value set to 1
+ | .------. | | '----------+--------+--------.
+ | | MUX- | | | | | |
+ | | Ctrl |-|-----+ .-----. .-----. .-----.
+ | '------' | | dev | | dev | | dev |
+ '------------' '-----' '-----' '-----'
+
+Required properties:
+- compatible: i2c-mux
+- i2c-parent: The phandle of the I2C bus that this multiplexer's master-side
+ port is connected to.
+- mux-controls: The phandle of the mux controller to use for operating the
+ mux.
+* Standard I2C mux properties. See i2c-mux.txt in this directory.
+* I2C child bus nodes. See i2c-mux.txt in this directory. The sub-bus number
+ is also the mux-controller state described in ../mux/mux-controller.txt
+
+Optional properties:
+- mux-locked: If present, explicitly allow unrelated I2C transactions on the
+ parent I2C adapter at these times:
+ + during setup of the multiplexer
+ + between setup of the multiplexer and the child bus I2C transaction
+ + between the child bus I2C transaction and releasing of the multiplexer
+ + during releasing of the multiplexer
+ However, I2C transactions to devices behind all I2C multiplexers connected
+ to the same parent adapter that this multiplexer is connected to are blocked
+ for the full duration of the complete multiplexed I2C transaction (i.e.
+ including the times covered by the above list).
+ If mux-locked is not present, the multiplexer is assumed to be parent-locked.
+ This means that no unrelated I2C transactions are allowed on the parent I2C
+ adapter for the complete multiplexed I2C transaction.
+ The properties of mux-locked and parent-locked multiplexers are discussed
+ in more detail in Documentation/i2c/i2c-topology.
+
+For each i2c child node, an I2C child bus will be created. They will
+be numbered based on their order in the device tree.
+
+Whenever an access is made to a device on a child bus, the value set
+in the relevant node's reg property will be set as the state in the
+mux controller.
+
+Example:
+ mux: mux-controller {
+ compatible = "gpio-mux";
+ #mux-control-cells = <0>;
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+ <&pioA 1 GPIO_ACTIVE_HIGH>;
+ };
+
+ i2c-mux {
+ compatible = "i2c-mux";
+ mux-locked;
+ i2c-parent = <&i2c1>;
+
+ mux-controls = <&mux>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c@1 {
+ reg = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ ssd1307: oled@3c {
+ compatible = "solomon,ssd1307fb-i2c";
+ reg = <0x3c>;
+ pwms = <&pwm 4 3000>;
+ reset-gpios = <&gpio2 7 1>;
+ reset-active-low;
+ };
+ };
+
+ i2c@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ pca9555: pca9555@20 {
+ compatible = "nxp,pca9555";
+ gpio-controller;
+ #gpio-cells = <2>;
+ reg = <0x20>;
+ };
+ };
+ };
--
2.1.4
^ permalink raw reply related
* [PATCH v14 09/11] i2c: i2c-mux-gpmux: new driver
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, linux-i2c, devicetree,
linux-iio, linux-doc, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel
In-Reply-To: <1493022995-16917-1-git-send-email-peda@axentia.se>
This is a general purpose i2c mux that uses a multiplexer controlled by
the multiplexer subsystem to do the muxing.
The user can select if the mux is to be mux-locked and parent-locked
as described in Documentation/i2c/i2c-topology.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/i2c/muxes/Kconfig | 13 +++
drivers/i2c/muxes/Makefile | 1 +
drivers/i2c/muxes/i2c-mux-gpmux.c | 173 ++++++++++++++++++++++++++++++++++++++
3 files changed, 187 insertions(+)
create mode 100644 drivers/i2c/muxes/i2c-mux-gpmux.c
diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig
index 10b3d17ae3ea..11115fb34f24 100644
--- a/drivers/i2c/muxes/Kconfig
+++ b/drivers/i2c/muxes/Kconfig
@@ -30,6 +30,19 @@ config I2C_MUX_GPIO
This driver can also be built as a module. If so, the module
will be called i2c-mux-gpio.
+config I2C_MUX_GPMUX
+ tristate "General Purpose I2C multiplexer"
+ select MULTIPLEXER
+ depends on OF
+ help
+ If you say yes to this option, support will be included for a
+ general purpose I2C multiplexer. This driver provides access to
+ I2C busses connected through a MUX, which in turn is controlled
+ by a MUX-controller from the MUX subsystem.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-mux-gpmux.
+
config I2C_MUX_PCA9541
tristate "NXP PCA9541 I2C Master Selector"
help
diff --git a/drivers/i2c/muxes/Makefile b/drivers/i2c/muxes/Makefile
index 9948fa45037f..af43c6c3e861 100644
--- a/drivers/i2c/muxes/Makefile
+++ b/drivers/i2c/muxes/Makefile
@@ -6,6 +6,7 @@ obj-$(CONFIG_I2C_ARB_GPIO_CHALLENGE) += i2c-arb-gpio-challenge.o
obj-$(CONFIG_I2C_DEMUX_PINCTRL) += i2c-demux-pinctrl.o
obj-$(CONFIG_I2C_MUX_GPIO) += i2c-mux-gpio.o
+obj-$(CONFIG_I2C_MUX_GPMUX) += i2c-mux-gpmux.o
obj-$(CONFIG_I2C_MUX_MLXCPLD) += i2c-mux-mlxcpld.o
obj-$(CONFIG_I2C_MUX_PCA9541) += i2c-mux-pca9541.o
obj-$(CONFIG_I2C_MUX_PCA954x) += i2c-mux-pca954x.o
diff --git a/drivers/i2c/muxes/i2c-mux-gpmux.c b/drivers/i2c/muxes/i2c-mux-gpmux.c
new file mode 100644
index 000000000000..92cf5f48afe6
--- /dev/null
+++ b/drivers/i2c/muxes/i2c-mux-gpmux.c
@@ -0,0 +1,173 @@
+/*
+ * General Purpose I2C multiplexer
+ *
+ * Copyright (C) 2017 Axentia Technologies AB
+ *
+ * Author: Peter Rosin <peda@axentia.se>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/module.h>
+#include <linux/mux/consumer.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+
+struct mux {
+ struct mux_control *control;
+
+ bool do_not_deselect;
+};
+
+static int i2c_mux_select(struct i2c_mux_core *muxc, u32 chan)
+{
+ struct mux *mux = i2c_mux_priv(muxc);
+ int ret;
+
+ ret = mux_control_select(mux->control, chan);
+ mux->do_not_deselect = ret < 0;
+
+ return ret;
+}
+
+static int i2c_mux_deselect(struct i2c_mux_core *muxc, u32 chan)
+{
+ struct mux *mux = i2c_mux_priv(muxc);
+
+ if (mux->do_not_deselect)
+ return 0;
+
+ return mux_control_deselect(mux->control);
+}
+
+static struct i2c_adapter *mux_parent_adapter(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct device_node *parent_np;
+ struct i2c_adapter *parent;
+
+ parent_np = of_parse_phandle(np, "i2c-parent", 0);
+ if (!parent_np) {
+ dev_err(dev, "Cannot parse i2c-parent\n");
+ return ERR_PTR(-ENODEV);
+ }
+ parent = of_find_i2c_adapter_by_node(parent_np);
+ of_node_put(parent_np);
+ if (!parent)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ return parent;
+}
+
+static const struct of_device_id i2c_mux_of_match[] = {
+ { .compatible = "i2c-mux", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, i2c_mux_of_match);
+
+static int i2c_mux_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct device_node *child;
+ struct i2c_mux_core *muxc;
+ struct mux *mux;
+ struct i2c_adapter *parent;
+ int children;
+ int ret;
+
+ if (!np)
+ return -ENODEV;
+
+ mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
+ if (!mux)
+ return -ENOMEM;
+
+ mux->control = devm_mux_control_get(dev, NULL);
+ if (IS_ERR(mux->control)) {
+ if (PTR_ERR(mux->control) != -EPROBE_DEFER)
+ dev_err(dev, "failed to get control-mux\n");
+ return PTR_ERR(mux->control);
+ }
+
+ parent = mux_parent_adapter(dev);
+ if (IS_ERR(parent)) {
+ if (PTR_ERR(parent) != -EPROBE_DEFER)
+ dev_err(dev, "failed to get i2c-parent adapter\n");
+ return PTR_ERR(parent);
+ }
+
+ children = of_get_child_count(np);
+
+ muxc = i2c_mux_alloc(parent, dev, children, 0, 0,
+ i2c_mux_select, i2c_mux_deselect);
+ if (!muxc) {
+ ret = -ENOMEM;
+ goto err_parent;
+ }
+ muxc->priv = mux;
+
+ platform_set_drvdata(pdev, muxc);
+
+ muxc->mux_locked = of_property_read_bool(np, "mux-locked");
+
+ for_each_child_of_node(np, child) {
+ u32 chan;
+
+ ret = of_property_read_u32(child, "reg", &chan);
+ if (ret < 0) {
+ dev_err(dev, "no reg property for node '%s'\n",
+ child->name);
+ goto err_children;
+ }
+
+ if (chan >= mux_control_states(mux->control)) {
+ dev_err(dev, "invalid reg %u\n", chan);
+ ret = -EINVAL;
+ goto err_children;
+ }
+
+ ret = i2c_mux_add_adapter(muxc, 0, chan, 0);
+ if (ret)
+ goto err_children;
+ }
+
+ dev_info(dev, "%d-port mux on %s adapter\n", children, parent->name);
+
+ return 0;
+
+err_children:
+ i2c_mux_del_adapters(muxc);
+err_parent:
+ i2c_put_adapter(parent);
+
+ return ret;
+}
+
+static int i2c_mux_remove(struct platform_device *pdev)
+{
+ struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
+
+ i2c_mux_del_adapters(muxc);
+ i2c_put_adapter(muxc->parent);
+
+ return 0;
+}
+
+static struct platform_driver i2c_mux_driver = {
+ .probe = i2c_mux_probe,
+ .remove = i2c_mux_remove,
+ .driver = {
+ .name = "i2c-mux-gpmux",
+ .of_match_table = i2c_mux_of_match,
+ },
+};
+module_platform_driver(i2c_mux_driver);
+
+MODULE_DESCRIPTION("General Purpose I2C multiplexer driver");
+MODULE_AUTHOR("Peter Rosin <peda@axentia.se>");
+MODULE_LICENSE("GPL v2");
--
2.1.4
^ permalink raw reply related
* [PATCH v14 10/11] dt-bindings: mux-adg792a: document devicetree bindings for ADG792A/G mux
From: Peter Rosin @ 2017-04-24 8:36 UTC (permalink / raw)
To: linux-kernel, Greg Kroah-Hartman
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, linux-i2c, devicetree,
linux-iio, linux-doc, Andrew Morton, Colin Ian King,
Paul Gortmaker, Philipp Zabel, kernel
In-Reply-To: <1493022995-16917-1-git-send-email-peda@axentia.se>
Analog Devices ADG792A/G is a triple 4:1 mux.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
.../devicetree/bindings/mux/adi,adg792a.txt | 75 ++++++++++++++++++++++
1 file changed, 75 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mux/adi,adg792a.txt
diff --git a/Documentation/devicetree/bindings/mux/adi,adg792a.txt b/Documentation/devicetree/bindings/mux/adi,adg792a.txt
new file mode 100644
index 000000000000..96b787a69f50
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/adi,adg792a.txt
@@ -0,0 +1,75 @@
+Bindings for Analog Devices ADG792A/G Triple 4:1 Multiplexers
+
+Required properties:
+- compatible : "adi,adg792a" or "adi,adg792g"
+- #mux-control-cells : <0> if parallel (the three muxes are bound together
+ with a single mux controller controlling all three muxes), or <1> if
+ not (one mux controller for each mux).
+* Standard mux-controller bindings as described in mux-controller.txt
+
+Optional properties for ADG792G:
+- gpio-controller : if present, #gpio-cells below is required.
+- #gpio-cells : should be <2>
+ - First cell is the GPO line number, i.e. 0 or 1
+ - Second cell is used to specify active high (0)
+ or active low (1)
+
+Optional properties:
+- idle-state : if present, array of states that the mux controllers will have
+ when idle. The special state MUX_IDLE_AS_IS is the default and
+ MUX_IDLE_DISCONNECT is also supported.
+
+States 0 through 3 correspond to signals A through D in the datasheet.
+
+Example:
+
+ /*
+ * Three independent mux controllers (of which one is used).
+ * Mux 0 is disconnected when idle, mux 1 idles in the previously
+ * selected state and mux 2 idles with signal B.
+ */
+ &i2c0 {
+ mux: mux-controller@50 {
+ compatible = "adi,adg792a";
+ reg = <0x50>;
+ #mux-control-cells = <1>;
+
+ idle-state = <MUX_IDLE_DISCONNECT MUX_IDLE_AS_IS 1>;
+ };
+ };
+
+ adc-mux {
+ compatible = "io-channel-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ mux-controls = <&mux 2>;
+
+ channels = "sync-1", "", "out";
+ };
+
+
+ /*
+ * Three parallel muxes with one mux controller, useful e.g. if
+ * the adc is differential, thus needing two signals to be muxed
+ * simultaneously for correct operation.
+ */
+ &i2c0 {
+ pmux: mux-controller@50 {
+ compatible = "adi,adg792a";
+ reg = <0x50>;
+ #mux-control-cells = <0>;
+
+ idle-state = <1>;
+ };
+ };
+
+ diff-adc-mux {
+ compatible = "io-channel-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ mux-controls = <&pmux>;
+
+ channels = "sync-1", "", "out";
+ };
--
2.1.4
^ permalink raw reply related
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