* Re: [PATCH 3/3] arm64: dts: exynos: Use macros for pinctrl configuration on Exynos7
From: Krzysztof Kozlowski @ 2017-01-18 15:01 UTC (permalink / raw)
To: Pankaj Dubey
Cc: linux-samsung-soc, linux-arm-kernel, devicetree, krzk, kgene,
robh+dt, sanath, javier, s.nawrocki, alim.akhtar
In-Reply-To: <1484718141-28785-4-git-send-email-pankaj.dubey@samsung.com>
On Wed, Jan 18, 2017 at 11:12:21AM +0530, Pankaj Dubey wrote:
> Usage of DTS macros instead of hard-coded numbers makes code easier to
> read. One does not have to remember which value means pull-up/down or
> specific driver strength.
>
> Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
> ---
> arch/arm64/boot/dts/exynos/exynos7-espresso.dts | 4 +-
> arch/arm64/boot/dts/exynos/exynos7-pinctrl.dtsi | 302 ++++++++++++------------
> 2 files changed, 154 insertions(+), 152 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/exynos/exynos7-espresso.dts b/arch/arm64/boot/dts/exynos/exynos7-espresso.dts
> index c528dd5..1b2db9f0 100644
> --- a/arch/arm64/boot/dts/exynos/exynos7-espresso.dts
> +++ b/arch/arm64/boot/dts/exynos/exynos7-espresso.dts
> @@ -328,8 +328,8 @@
> &pinctrl_alive {
> pmic_irq: pmic-irq {
> samsung,pins = "gpa0-2";
> - samsung,pin-pud = <3>;
> - samsung,pin-drv = <3>;
> + samsung,pin-pud = <EXYNOS_PIN_PULL_UP>;
> + samsung,pin-drv = <EXYNOS4_PIN_DRV_LV3>;
> };
> };
This is not equal (value 3 => 1). If the change was intended, please do
in separate patch.
Rest looks fine.
Best regards,
Krzysztof
^ permalink raw reply
* Re: [PATCH 02/11] [media] s5p-mfc: Adding initial support for MFC v10.10
From: Andrzej Hajda @ 2017-01-18 15:10 UTC (permalink / raw)
To: Smitha T Murthy, linux-arm-kernel, linux-media, linux-kernel
Cc: kyungmin.park, kamil, jtp.park, mchehab, pankaj.dubey, krzk,
m.szyprowski, s.nawrocki, Rob Herring, devicetree
In-Reply-To: <1484733729-25371-3-git-send-email-smitha.t@samsung.com>
On 18.01.2017 11:02, Smitha T Murthy wrote:
> Adding the support for MFC v10.10, with new register file and
> necessary hw control, decoder, encoder and structural changes.
>
> CC: Rob Herring <robh+dt@kernel.org>
> CC: devicetree@vger.kernel.org
> Signed-off-by: Smitha T Murthy <smitha.t@samsung.com>
> ---
> .../devicetree/bindings/media/s5p-mfc.txt | 1 +
> drivers/media/platform/s5p-mfc/regs-mfc-v10.h | 36 ++++++++++++++++
> drivers/media/platform/s5p-mfc/s5p_mfc.c | 30 +++++++++++++
> drivers/media/platform/s5p-mfc/s5p_mfc_common.h | 4 +-
> drivers/media/platform/s5p-mfc/s5p_mfc_ctrl.c | 4 ++
> drivers/media/platform/s5p-mfc/s5p_mfc_dec.c | 44 +++++++++++---------
> drivers/media/platform/s5p-mfc/s5p_mfc_enc.c | 21 +++++----
> drivers/media/platform/s5p-mfc/s5p_mfc_opr_v6.c | 9 +++-
> drivers/media/platform/s5p-mfc/s5p_mfc_opr_v6.h | 2 +
> 9 files changed, 118 insertions(+), 33 deletions(-)
> create mode 100644 drivers/media/platform/s5p-mfc/regs-mfc-v10.h
>
> diff --git a/Documentation/devicetree/bindings/media/s5p-mfc.txt b/Documentation/devicetree/bindings/media/s5p-mfc.txt
> index 2c90128..b70c613 100644
> --- a/Documentation/devicetree/bindings/media/s5p-mfc.txt
> +++ b/Documentation/devicetree/bindings/media/s5p-mfc.txt
> @@ -13,6 +13,7 @@ Required properties:
> (c) "samsung,mfc-v7" for MFC v7 present in Exynos5420 SoC
> (d) "samsung,mfc-v8" for MFC v8 present in Exynos5800 SoC
> (e) "samsung,exynos5433-mfc" for MFC v8 present in Exynos5433 SoC
> + (f) "samsung,mfc-v10" for MFC v10 present in a variant of Exynos7 SoC
Could you specify explicitly SoC version(s), Exynos7 is misleading.
Btw are there plans to upstream platforms using this MFC?
>
> - reg : Physical base address of the IP registers and length of memory
> mapped region.
> diff --git a/drivers/media/platform/s5p-mfc/regs-mfc-v10.h b/drivers/media/platform/s5p-mfc/regs-mfc-v10.h
> new file mode 100644
> index 0000000..bd671a5
> --- /dev/null
> +++ b/drivers/media/platform/s5p-mfc/regs-mfc-v10.h
> @@ -0,0 +1,36 @@
> +/*
> + * Register definition file for Samsung MFC V10.x Interface (FIMV) driver
> + *
> + * Copyright (c) 2017 Samsung Electronics Co., Ltd.
> + * http://www.samsung.com/
> + *
> + * 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 _REGS_MFC_V10_H
> +#define _REGS_MFC_V10_H
> +
> +#include <linux/sizes.h>
> +#include "regs-mfc-v8.h"
> +
> +/* MFCv10 register definitions*/
> +#define S5P_FIMV_MFC_CLOCK_OFF_V10 0x7120
> +#define S5P_FIMV_MFC_STATE_V10 0x7124
> +
> +/* MFCv10 Context buffer sizes */
> +#define MFC_CTX_BUF_SIZE_V10 (30 * SZ_1K) /* 30KB */
> +#define MFC_H264_DEC_CTX_BUF_SIZE_V10 (2 * SZ_1M) /* 2MB */
> +#define MFC_OTHER_DEC_CTX_BUF_SIZE_V10 (20 * SZ_1K) /* 20KB */
> +#define MFC_H264_ENC_CTX_BUF_SIZE_V10 (100 * SZ_1K) /* 100KB */
> +#define MFC_OTHER_ENC_CTX_BUF_SIZE_V10 (15 * SZ_1K) /* 15KB */
> +
> +/* MFCv10 variant defines */
> +#define MAX_FW_SIZE_V10 (SZ_1M) /* 1MB */
> +#define MAX_CPB_SIZE_V10 (3 * SZ_1M) /* 3MB */
> +#define MFC_VERSION_V10 0xA0
> +#define MFC_NUM_PORTS_V10 1
> +
> +#endif /*_REGS_MFC_V10_H*/
> +
> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc.c b/drivers/media/platform/s5p-mfc/s5p_mfc.c
> index bb0a588..a043cce 100644
> --- a/drivers/media/platform/s5p-mfc/s5p_mfc.c
> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc.c
> @@ -1542,6 +1542,33 @@ static int s5p_mfc_resume(struct device *dev)
> .num_clocks = 3,
> };
>
> +static struct s5p_mfc_buf_size_v6 mfc_buf_size_v10 = {
> + .dev_ctx = MFC_CTX_BUF_SIZE_V10,
> + .h264_dec_ctx = MFC_H264_DEC_CTX_BUF_SIZE_V10,
> + .other_dec_ctx = MFC_OTHER_DEC_CTX_BUF_SIZE_V10,
> + .h264_enc_ctx = MFC_H264_ENC_CTX_BUF_SIZE_V10,
> + .other_enc_ctx = MFC_OTHER_ENC_CTX_BUF_SIZE_V10,
> +};
> +
> +static struct s5p_mfc_buf_size buf_size_v10 = {
> + .fw = MAX_FW_SIZE_V10,
> + .cpb = MAX_CPB_SIZE_V10,
> + .priv = &mfc_buf_size_v10,
> +};
> +
> +static struct s5p_mfc_buf_align mfc_buf_align_v10 = {
> + .base = 0,
> +};
> +
> +static struct s5p_mfc_variant mfc_drvdata_v10 = {
> + .version = MFC_VERSION_V10,
> + .version_bit = MFC_V10_BIT,
> + .port_num = MFC_NUM_PORTS_V10,
> + .buf_size = &buf_size_v10,
> + .buf_align = &mfc_buf_align_v10,
> + .fw_name[0] = "s5p-mfc-v10.fw",
Is firmware file publicly available? Sent to firmware repository?
> +};
> +
> static const struct of_device_id exynos_mfc_match[] = {
> {
> .compatible = "samsung,mfc-v5",
> @@ -1558,6 +1585,9 @@ static int s5p_mfc_resume(struct device *dev)
> }, {
> .compatible = "samsung,exynos5433-mfc",
> .data = &mfc_drvdata_v8_5433,
> + }, {
> + .compatible = "samsung,mfc-v10",
> + .data = &mfc_drvdata_v10,
> },
> {},
> };
> diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc_common.h b/drivers/media/platform/s5p-mfc/s5p_mfc_common.h
> index b45d18c..1941c63 100644
> --- a/drivers/media/platform/s5p-mfc/s5p_mfc_common.h
> +++ b/drivers/media/platform/s5p-mfc/s5p_mfc_common.h
> @@ -23,7 +23,7 @@
> #include <media/v4l2-ioctl.h>
> #include <media/videobuf2-v4l2.h>
> #include "regs-mfc.h"
> -#include "regs-mfc-v8.h"
> +#include "regs-mfc-v10.h"
>
> #define S5P_MFC_NAME "s5p-mfc"
>
> @@ -723,11 +723,13 @@ struct mfc_control {
> #define IS_MFCV6_PLUS(dev) (dev->variant->version >= 0x60 ? 1 : 0)
> #define IS_MFCV7_PLUS(dev) (dev->variant->version >= 0x70 ? 1 : 0)
> #define IS_MFCV8_PLUS(dev) (dev->variant->version >= 0x80 ? 1 : 0)
> +#define IS_MFCV10(dev) (dev->variant->version >= 0xA0 ? 1 : 0)
>
> #define MFC_V5_BIT BIT(0)
> #define MFC_V6_BIT BIT(1)
> #define MFC_V7_BIT BIT(2)
> #define MFC_V8_BIT BIT(3)
> +#define MFC_V10_BIT BIT(5)
I think you can use BIT(4) here.
Regards
Andrzej
^ permalink raw reply
* RE: [PATCH v2 2/3] mmc: sh_mobile_sdhi: explain clock bindings
From: Chris Brandt @ 2017-01-18 15:11 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Ulf Hansson, Rob Herring, Mark Rutland, Simon Horman,
Wolfram Sang, devicetree@vger.kernel.org, Linux MMC List,
Linux-Renesas
In-Reply-To: <CAMuHMdVqgrfPVCz68z9vqX_5GhKVbF-FndraTk40UrBdMMKwYw@mail.gmail.com>
Hi Geert,
On Wednesday, January 18, 2017, Geert Uytterhoeven wrote:
> > +- clocks: Most controllers only have 1 clock source per cahnnel.
> However, some
> > + have 2. If 2 clocks are specified, you must name them as
> "core" and
> > + "carddetect". If the controller only has 1 clock, naming is
> > +not
>
> Perhaps this clock should just be called "cd", as that's already an
> established abbreviation for card detect in MMC DT bindings?
OK, I'll change it.
Thanks,
Chris
^ permalink raw reply
* Re: [PATCH 2/2] ARM: DTS: Fix register map for virt-capable GIC
From: Javier Martinez Canillas @ 2017-01-18 15:16 UTC (permalink / raw)
To: Marc Zyngier, linux-kernel, devicetree, linux-arm-kernel
Cc: Thomas Gleixner, Jason Cooper, Rob Herring, Mark Rutland,
Tsahee Zidenberg, Antoine Tenart, Russell King,
Benoît Cousson, Tony Lindgren, Kukjin Kim,
Krzysztof Kozlowski, Shawn Guo, Sascha Hauer, Fabio Estevam,
Santosh Shilimkar, Matthias Brugger, Simon Horman, Magnus Damm,
Heiko Stuebner
In-Reply-To: <1484736811-24002-3-git-send-email-marc.zyngier@arm.com>
Hello Marc,
On 01/18/2017 07:53 AM, Marc Zyngier wrote:
> Since everybody copied my own mistake from the DT binding example,
> let's address all the offenders in one swift go.
>
> Most of them got the CPU interface size wrong (4kB, while it should
> be 8kB), except for both keystone platforms which got the control
> interface wrong (4kB instead of 8kB).
>
> In the couple of cases were I knew for sure what implementation
> was used, I've added the "arm,gic-400" compatible string. I'm 99%
> sure that this is what everyong is using, but short of having the
> TRM for all the other SoCs, I've let them alone.
>
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> ---
> arch/arm/boot/dts/exynos3250.dtsi | 2 +-
> arch/arm/boot/dts/exynos5.dtsi | 2 +-
> arch/arm/boot/dts/exynos5260.dtsi | 2 +-
> arch/arm/boot/dts/exynos5440.dtsi | 2 +-
I've looked at the Exynos5250 and Exynos5420 TRM and both say that adopts
GIC-400, so I think it's safe for you to also update the compatible in the
exynos5.dtsi. Unfortunately I don't have manuals for 3250, 5260 and 5440.
The register map changes looks good to me, so for Exynos:
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Best regards,
--
Javier Martinez Canillas
Open Source Group
Samsung Research America
^ permalink raw reply
* Re: [PATCH v9 2/5] i2c: Add STM32F4 I2C driver
From: M'boumba Cedric Madianga @ 2017-01-18 15:21 UTC (permalink / raw)
To: Uwe Kleine-König
Cc: Wolfram Sang, Rob Herring, Maxime Coquelin, Alexandre Torgue,
Linus Walleij, Patrice Chotard, Russell King,
linux-i2c-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r,
linux-kernel-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <20170117193752.e6hju25w74bb4i4z-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
Hello Uwe,
2017-01-17 20:37 GMT+01:00 Uwe Kleine-König <u.kleine-koenig@pengutronix.de>:
> Hello,
>
> On Tue, Jan 17, 2017 at 04:26:58PM +0100, M'boumba Cedric Madianga wrote:
>> +static void stm32f4_i2c_set_rise_time(struct stm32f4_i2c_dev *i2c_dev)
>> +{
>> + u32 freq = DIV_ROUND_UP(i2c_dev->parent_rate, HZ_TO_MHZ);
>> + u32 trise;
>> +
>> + /*
>> + * These bits must be programmed with the maximum SCL rise time given in
>> + * the I2C bus specification, incremented by 1.
>> + *
>> + * In standard mode, the maximum allowed SCL rise time is 1000 ns.
>> + * If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to
>> + * 0x08 so period = 125 ns therefore the TRISE[5:0] bits must be
>> + * programmed with 09h.(1000 ns / 125 ns = 8 + 1)
>
> * programmed with 0x9.
> (1000 ns / 125 ns = 8)
>
>> + * So, for I2C standard mode TRISE = FREQ[5:0] + 1
>> + *
>> + * In fast mode, the maximum allowed SCL rise time is 300 ns.
>> + * If, in the I2C_CR2 register, the value of FREQ[5:0] bits is equal to
>> + * 0x08 so period = 125 ns therefore the TRISE[5:0] bits must be
>> + * programmed with 03h.(300 ns / 125 ns = 2 + 1)
>
> as above s/03h/0x3/;
ok
> s/.(/. (/;
ok
> s/+ 1//;
This formula is use to understand how we find the result 0x3
So, 0x3 => 300 ns / 125ns = 2 + 1
>
>> + * So, for I2C fast mode TRISE = FREQ[5:0] * 300 / 1000 + 1
>> + */
>> + if (i2c_dev->speed == STM32F4_I2C_SPEED_STANDARD)
>> + trise = freq + 1;
>> + else
>> + trise = freq * 300 / 1000 + 1;
>
> I'd use
>
> * 3 / 10
>
> without downside and lesser chance to overflow.
There is no chance of overflow as the max freq value allowed is 46
>
>> +
>> + writel_relaxed(STM32F4_I2C_TRISE_VALUE(trise),
>> + i2c_dev->base + STM32F4_I2C_TRISE);
>> +}
>> +
>> +static void stm32f4_i2c_set_speed_mode(struct stm32f4_i2c_dev *i2c_dev)
>> +{
>> + u32 val;
>> + u32 ccr = 0;
>> +
>> + if (i2c_dev->speed == STM32F4_I2C_SPEED_STANDARD) {
>> + /*
>> + * In standard mode:
>> + * t_scl_high = t_scl_low = CCR * I2C parent clk period
>> + * So to reach 100 kHz, we have:
>> + * CCR = I2C parent rate / 100 kHz >> 1
>> + *
>> + * For example with parent rate = 2 MHz:
>> + * CCR = 2000000 / (100000 << 1) = 10
>> + * t_scl_high = t_scl_low = 10 * (1 / 2000000) = 5000 ns
>> + * t_scl_high + t_scl_low = 10000 ns so 100 kHz is reached
>> + */
>> + val = i2c_dev->parent_rate / (100000 << 1);
>> + } else {
>> + /*
>> + * In fast mode, we compute CCR with duty = 0 as with low
>> + * frequencies we are not able to reach 400 kHz.
>> + * In that case:
>> + * t_scl_high = CCR * I2C parent clk period
>> + * t_scl_low = 2 * CCR * I2C parent clk period
>> + * So, CCR = I2C parent rate / (400 kHz * 3)
>> + *
>> + * For example with parent rate = 6 MHz:
>> + * CCR = 6000000 / (400000 * 3) = 5
>> + * t_scl_high = 5 * (1 / 6000000) = 833 ns > 600 ns
>> + * t_scl_low = 2 * 5 * (1 / 6000000) = 1667 ns > 1300 ns
>> + * t_scl_high + t_scl_low = 2500 ns so 400 kHz is reached
>> + */
>
> Huh, that's surprising. So you don't use DUTY any more. I found two
> hints in the manual that contradict here:
Yes with the above formula we could use duty = 0 by default
>
> f_{PCLK1} must be at least 2 MHz to achieve Sm mode I2C frequencies
STM32F4_I2C_MIN_STANDARD_FREQ = 2
> It must be at least 4 MHz to achieve Fm mode I2C frequencies.
STM32F4_I2C_MIN_FAST_FREQ = 6
> It must be a multiple of 10MHz to reach the 400 kHz maximum I2C Fm mode clock.
If we use this rule only 3 values are allowed 10 Mhz, 20 Mhz, 30 Mhz and 40 Mhz.
It is very restrictive.
So I don't take it into account in order to have more frequencies even
if 400 Khz is not reached.
Indeed, in many cases we are very close to 400 Khz.
For example, the default I2C parent clock in my board is 45 Mhz
I reach 395 kHz in theory and 390 kHz by testing.
I am in Fast mode but not with the max freq but very close.
>
> and
>
> [...]
> If DUTY = 1: (to reach 400 kHz)
>
> Strange.
>
>> + val = DIV_ROUND_UP(i2c_dev->parent_rate, 400000 * 3);
>
> the manual reads:
>
> The minimum allowed value is 0x04, except in FAST DUTY mode
> where the minimum allowed value is 0x01
>
> You don't check for that, right?
As the minimum freq value is 6 Mhz in fast mode the minimum CCR is 5
as described in the comment.
So I don't need to check that again as it is already done by checking
parent frequency.
> CCR is 11 bits wide. A comment confirming that this cannot overflow
> would be nice.
Again there is no chance of overflow thanks to parent frequency check
>
> + /* select Fast Mode */
>> + ccr |= STM32F4_I2C_CCR_FS;
ok
>
> I didn't check the rest of the code, so let's assume it's good :-)
ok Thanks
>
> Best regards
> Uwe
>
> --
> Pengutronix e.K. | Uwe Kleine-König |
> Industrial Linux Solutions | http://www.pengutronix.de/ |
--
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^ permalink raw reply
* Re: [PATCH 2/2] ARM: DTS: Fix register map for virt-capable GIC
From: Marc Zyngier @ 2017-01-18 15:26 UTC (permalink / raw)
To: Javier Martinez Canillas, linux-kernel, devicetree,
linux-arm-kernel
Cc: Thomas Gleixner, Jason Cooper, Rob Herring, Mark Rutland,
Tsahee Zidenberg, Antoine Tenart, Russell King,
Benoît Cousson, Tony Lindgren, Kukjin Kim,
Krzysztof Kozlowski, Shawn Guo, Sascha Hauer, Fabio Estevam,
Santosh Shilimkar, Matthias Brugger, Simon Horman, Magnus Damm,
Heiko Stuebner
In-Reply-To: <e2295a5d-3224-1198-8b46-f45b153b540a@osg.samsung.com>
On 18/01/17 15:16, Javier Martinez Canillas wrote:
> Hello Marc,
>
> On 01/18/2017 07:53 AM, Marc Zyngier wrote:
>> Since everybody copied my own mistake from the DT binding example,
>> let's address all the offenders in one swift go.
>>
>> Most of them got the CPU interface size wrong (4kB, while it should
>> be 8kB), except for both keystone platforms which got the control
>> interface wrong (4kB instead of 8kB).
>>
>> In the couple of cases were I knew for sure what implementation
>> was used, I've added the "arm,gic-400" compatible string. I'm 99%
>> sure that this is what everyong is using, but short of having the
>> TRM for all the other SoCs, I've let them alone.
>>
>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
>> ---
>> arch/arm/boot/dts/exynos3250.dtsi | 2 +-
>> arch/arm/boot/dts/exynos5.dtsi | 2 +-
>> arch/arm/boot/dts/exynos5260.dtsi | 2 +-
>> arch/arm/boot/dts/exynos5440.dtsi | 2 +-
>
> I've looked at the Exynos5250 and Exynos5420 TRM and both say that adopts
> GIC-400, so I think it's safe for you to also update the compatible in the
> exynos5.dtsi. Unfortunately I don't have manuals for 3250, 5260 and 5440.
Thanks for taking the time to find out, I'll update the patch.
>
> The register map changes looks good to me, so for Exynos:
>
> Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Thank you.
M.
--
Jazz is not dead. It just smells funny...
^ permalink raw reply
* Re: Initializing MAC address at run-time
From: Robin Murphy @ 2017-01-18 15:35 UTC (permalink / raw)
To: Mason
Cc: Mark Rutland, DT, Arnd Bergmann, Kevin Hilman, netdev,
Thibaud Cornic, Uwe Kleine-Konig, Linux ARM
In-Reply-To: <20170118144528.GH3231@leverpostej>
On 18/01/17 14:45, Mark Rutland wrote:
> On Wed, Jan 18, 2017 at 03:03:57PM +0100, Mason wrote:
>> Hello,
>>
>> When my system boots up, eth0 is given a seemingly random MAC address.
>>
>> [ 0.950734] nb8800 26000.ethernet eth0: MAC address ba:de:d6:38:b8:38
>> [ 0.957334] nb8800 26000.ethernet eth0: MAC address 6e:f1:48:de:d6:c4
>>
>>
>> The DT node for eth0 is:
>>
>> eth0: ethernet@26000 {
>> compatible = "sigma,smp8734-ethernet";
>> reg = <0x26000 0x800>;
>> interrupts = <38 IRQ_TYPE_LEVEL_HIGH>;
>> clocks = <&clkgen SYS_CLK>;
>> };
>>
>> Documentation/devicetree/bindings/net/ethernet.txt mentions
>> - local-mac-address: array of 6 bytes, specifies the MAC address that was
>> assigned to the network device;
>>
>> And indeed, if I define this property, eth0 ends up with the MAC address
>> I specify in the device tree. But of course, I don't want all my boards
>> to share the same MAC address. Every interface has a unique MAC address.
>>
>> In fact, the boot loader (not Uboot, a custom non-DT boot loader) stores
>> the MAC address somewhere in MMIO space, in some weird custom format.
>>
>> So, at init, I can find the MAC address, and dynamically insert the
>> "local-mac-address" property in the eth0 node.
>
> To me it sounds very convoluted to do this from the kernel, to pass
> information back to itself. I don't think this is the best way to handle
> this.
>
>> Is there another (better) way to do this?
>>
>> I'll post my code below, for illustration purpose.
>>
>> Mark suggested this can be done from user-space, but I can't do that,
>> because I'm using an NFS rootfs, so I need the network before I even
>> have a user-space. And the DHCP server is configured to serve different
>> root filesystems, based on the MAC address.
>
> That's not quite what I said. I asked whether your information was
> coming from userspace or from a kernel driver.
>
> My suggestion was that this should be done in the probe path somehow,
> by describing the relationship between the ethernet controller and the
> device containing the MAC information.
>
> e.g. on the ethernet device, have a phandle (and perhaps some other
> args) describinng the device containing the MAC, and how to extract it.
>
> That way, in the ethernet probe path we can go and look up the MAC
> address from the provider of that information.
See Documentation/devicetree/bindings/mfd/syscon.txt and
bindings/drivers with syscon dependencies. Essentially, you would use a
syscon node to describe "somewhere in MMIO space", then your ethernet
driver probe routine simply grabs the regmap, pulls out the MAC and goes
from there.
Be warned that the above represents the totality of my technical
knowledge on the subject ;) My experience is in hacking up DTs for
drivers which already use this mechanism, rather than in implementing it.
Robin.
>> I need to do something similar with the NAND partitions. The boot loader
>> stores the partition offsets somewhere, and I need to pass this info
>> to the NAND framework, so I assumed that inserting the corresponding
>> properties at run-time was the correct way to do it.
>
> I would say similar could happen here.
>
> Thanks,
> Mark.
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
^ permalink raw reply
* Re: [PATCH] arm64: dts: exynos: Remove address node from usb parent node
From: Javier Martinez Canillas @ 2017-01-18 15:36 UTC (permalink / raw)
To: Chanwoo Choi, Pankaj Dubey, devicetree, linux-kernel,
linux-samsung-soc
Cc: robh+dt, krzk, kgene
In-Reply-To: <587F137B.6070109@samsung.com>
Hello,
On 01/18/2017 04:04 AM, Chanwoo Choi wrote:
> Hi Pankaj,
>
> This issue already posted by Javier Martinez Canillas[1].
> Maybe, he will post v2.
>
That's correct, I didn't post a v2 since I was waiting for feedback
from the DT maintainers on patches 1/2 and 2/2 from the same series:
https://www.spinics.net/lists/arm-kernel/msg553286.html
But I'll re-spin just this patch since the changes are independent.
Best regards,
--
Javier Martinez Canillas
Open Source Group
Samsung Research America
^ permalink raw reply
* [PATCH v3] arm64: dts: exynos: Remove unneeded unit names in Exynos5433 nodes
From: Javier Martinez Canillas @ 2017-01-18 15:50 UTC (permalink / raw)
To: linux-kernel
Cc: Andi Shyti, Pankaj Dubey, Chanwoo Choi, Javier Martinez Canillas,
devicetree, Kukjin Kim, Catalin Marinas, linux-samsung-soc,
Rob Herring, Will Deacon, Mark Rutland, Krzysztof Kozlowski,
linux-arm-kernel
The "samsung,exynos5433-mipi-video-phy" and "samsung,exynos5250-dwusb3"
DT bindings don't specify a reg property for these nodes, so having a
unit name leads to the following DTC warnings:
Node /soc/video-phy@105c0710 has a unit name, but no reg property
Node /soc/usb@15400000 has a unit name, but no reg property
Node /soc/usb@15a00000 has a unit name, but no reg property
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
---
Changes in v3:
- Use proper device node names, suggested by Krzysztof.
Changes in v2:
- Fix subject line since I forgot the "exynos" prefix.
arch/arm64/boot/dts/exynos/exynos5433.dtsi | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/boot/dts/exynos/exynos5433.dtsi b/arch/arm64/boot/dts/exynos/exynos5433.dtsi
index 59788d89b686..57c7bbeb65a7 100644
--- a/arch/arm64/boot/dts/exynos/exynos5433.dtsi
+++ b/arch/arm64/boot/dts/exynos/exynos5433.dtsi
@@ -706,7 +706,7 @@
interrupts = <GIC_PPI 9 0xf04>;
};
- mipi_phy: video-phy@105c0710 {
+ mipi_phy: video-phy {
compatible = "samsung,exynos5433-mipi-video-phy";
#phy-cells = <1>;
samsung,pmu-syscon = <&pmu_system_controller>;
@@ -1357,7 +1357,7 @@
status = "disabled";
};
- usbdrd30: usb@15400000 {
+ usbdrd30: usbdrd {
compatible = "samsung,exynos5250-dwusb3";
clocks = <&cmu_fsys CLK_ACLK_USBDRD30>,
<&cmu_fsys CLK_SCLK_USBDRD30>;
@@ -1404,7 +1404,7 @@
status = "disabled";
};
- usbhost30: usb@15a00000 {
+ usbhost30: usbhost {
compatible = "samsung,exynos5250-dwusb3";
clocks = <&cmu_fsys CLK_ACLK_USBHOST30>,
<&cmu_fsys CLK_SCLK_USBHOST30>;
--
2.7.4
^ permalink raw reply related
* [PATCH v8 00/12] mux controller abstraction and iio/i2c muxes
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
Hi!
v7 -> v8 changes
- 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
- 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
- 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
- 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
- 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
- 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
- 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.
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
generic i2c mux driver. The new i2c mux I called "simple"
since it is only hooking the i2c muxing and the new mux
controller (much like the alsa simple card driver does for ASoC).
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) to be i2c-mux-simple muxes.
I'm using an rwsem to lock a mux, but that isn't really a
perfect fit. Is there a better locking primitive that I don't
know about that fits better? I had a mutex at one point, but
that didn't allow any concurrent accesses at all. At least
the rwsem allows concurrent access as long as all users
agree on the mux state, but I suspect that the rwsem will
degrade to the mutex situation pretty quickly if there is
any contention.
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...
Cheers,
peda
Peter Rosin (12):
devres: trivial whitespace fix
dt-bindings: document devicetree bindings for mux-controllers and
mux-gpio
mux: minimal mux subsystem and gpio-based mux controller
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-simple: document i2c-mux-simple bindings
i2c: i2c-mux-simple: new driver
dt-bindings: mux-adg792a: document devicetree bindings for ADG792A/G
mux
mux: adg792a: add mux controller driver for ADG792A/G
dt-bindings: simplified bindings for single-user gpio mux
mux: support simplified bindings for single-user gpio mux
.../devicetree/bindings/i2c/i2c-mux-simple.txt | 81 ++++
.../bindings/iio/multiplexer/io-channel-mux.txt | 39 ++
.../devicetree/bindings/mux/mux-adg792a.txt | 79 ++++
.../devicetree/bindings/mux/mux-controller.txt | 153 +++++++
Documentation/devicetree/bindings/mux/mux-gpio.txt | 68 +++
Documentation/driver-model/devres.txt | 10 +-
MAINTAINERS | 14 +
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/i2c/muxes/Kconfig | 13 +
drivers/i2c/muxes/Makefile | 1 +
drivers/i2c/muxes/i2c-mux-simple.c | 182 ++++++++
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 | 456 +++++++++++++++++++++
drivers/mux/Kconfig | 42 ++
drivers/mux/Makefile | 7 +
drivers/mux/mux-adg792a.c | 167 ++++++++
drivers/mux/mux-core.c | 425 +++++++++++++++++++
drivers/mux/mux-gpio.c | 129 ++++++
drivers/mux/mux-gpio.h | 13 +
include/linux/iio/consumer.h | 37 ++
include/linux/mux.h | 244 +++++++++++
26 files changed, 2248 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt
create mode 100644 Documentation/devicetree/bindings/iio/multiplexer/io-channel-mux.txt
create mode 100644 Documentation/devicetree/bindings/mux/mux-adg792a.txt
create mode 100644 Documentation/devicetree/bindings/mux/mux-controller.txt
create mode 100644 Documentation/devicetree/bindings/mux/mux-gpio.txt
create mode 100644 drivers/i2c/muxes/i2c-mux-simple.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 drivers/mux/mux-gpio.h
create mode 100644 include/linux/mux.h
--
2.1.4
^ permalink raw reply
* [PATCH v8 01/12] devres: trivial whitespace fix
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-git-send-email-peda@axentia.se>
Everything else is indented with two spaces, so fix the odd one out.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
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 ca9d1eb46bc0..dc51fb024190 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -330,7 +330,7 @@ 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 v8 02/12] dt-bindings: document devicetree bindings for mux-controllers and mux-gpio
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-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
controlled.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
.../devicetree/bindings/mux/mux-controller.txt | 127 +++++++++++++++++++++
Documentation/devicetree/bindings/mux/mux-gpio.txt | 68 +++++++++++
MAINTAINERS | 5 +
3 files changed, 200 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mux/mux-controller.txt
create mode 100644 Documentation/devicetree/bindings/mux/mux-gpio.txt
diff --git a/Documentation/devicetree/bindings/mux/mux-controller.txt b/Documentation/devicetree/bindings/mux/mux-controller.txt
new file mode 100644
index 000000000000..42b2177e5ae1
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/mux-controller.txt
@@ -0,0 +1,127 @@
+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 = "mux-gpio";
+ #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.
+
+ /*
+ * 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 = "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-1", "in", "out", "sync-2";
+ };
+
+ i2c-mux {
+ compatible = "i2c-mux-simple,mux-locked";
+ 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.
+
+An example mux controller might look like this:
+
+ mux: adg792a@50 {
+ compatible = "adi,adg792a";
+ reg = <0x50>;
+ #mux-control-cells = <1>;
+ };
diff --git a/Documentation/devicetree/bindings/mux/mux-gpio.txt b/Documentation/devicetree/bindings/mux/mux-gpio.txt
new file mode 100644
index 000000000000..8f6bda6f9d78
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/mux-gpio.txt
@@ -0,0 +1,68 @@
+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 : "mux-gpio"
+- 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 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 = "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-1", "in", "out", "sync-2";
+ };
+
+ i2c-mux {
+ compatible = "i2c-mux-simple,mux-locked";
+ 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/MAINTAINERS b/MAINTAINERS
index 40de344ba0e6..be57f5b8f2c2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8469,6 +8469,11 @@ 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/
+
MULTISOUND SOUND DRIVER
M: Andrew Veliath <andrewtv@usa.net>
S: Maintained
--
2.1.4
^ permalink raw reply related
* [PATCH v8 03/12] mux: minimal mux subsystem and gpio-based mux controller
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-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.
This new mux controller subsystem initially comes with a single backend
driver that controls gpio based multiplexers. Even though not needed by
this initial driver, the mux controller subsystem is prepared to handle
chips with multiple (independent) mux controllers.
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
Documentation/driver-model/devres.txt | 8 +
MAINTAINERS | 2 +
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/mux/Kconfig | 33 +++
drivers/mux/Makefile | 6 +
drivers/mux/mux-core.c | 406 ++++++++++++++++++++++++++++++++++
drivers/mux/mux-gpio.c | 115 ++++++++++
include/linux/mux.h | 244 ++++++++++++++++++++
9 files changed, 817 insertions(+)
create mode 100644 drivers/mux/Kconfig
create mode 100644 drivers/mux/Makefile
create mode 100644 drivers/mux/mux-core.c
create mode 100644 drivers/mux/mux-gpio.c
create mode 100644 include/linux/mux.h
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index dc51fb024190..1e9ae701a587 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -332,6 +332,14 @@ 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 be57f5b8f2c2..e4fac17e0fa4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8473,6 +8473,8 @@ MULTIPLEXER SUBSYSTEM
M: Peter Rosin <peda@axentia.se>
S: Maintained
F: Documentation/devicetree/bindings/mux/
+F: include/linux/mux.h
+F: drivers/mux/
MULTISOUND SOUND DRIVER
M: Andrew Veliath <andrewtv@usa.net>
diff --git a/drivers/Kconfig b/drivers/Kconfig
index e1e2066cecdb..ea231018089e 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -202,4 +202,6 @@ source "drivers/hwtracing/intel_th/Kconfig"
source "drivers/fpga/Kconfig"
+source "drivers/mux/Kconfig"
+
endmenu
diff --git a/drivers/Makefile b/drivers/Makefile
index 060026a02f59..8ff0460bb2f8 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -173,3 +173,4 @@ obj-$(CONFIG_STM) += hwtracing/stm/
obj-$(CONFIG_ANDROID) += android/
obj-$(CONFIG_NVMEM) += nvmem/
obj-$(CONFIG_FPGA) += fpga/
+obj-$(CONFIG_MULTIPLEXER) += mux/
diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
new file mode 100644
index 000000000000..57e6f4e5fda9
--- /dev/null
+++ b/drivers/mux/Kconfig
@@ -0,0 +1,33 @@
+#
+# Multiplexer devices
+#
+
+menuconfig MULTIPLEXER
+ bool "Multiplexer subsystem"
+ help
+ Multiplexer controller subsystem. Multiplexers are used in a
+ variety of settings, and this subsystem abstracts their use
+ so that the rest of the kernel sees a common interface. When
+ multiple parallel multiplexers are controlled by one single
+ multiplexer controller, this subsystem also coordinates the
+ multiplexer accesses.
+
+ If unsure, say no.
+
+if MULTIPLEXER
+
+config MUX_GPIO
+ tristate "GPIO-controlled Multiplexer"
+ depends on OF && GPIOLIB
+ help
+ GPIO-controlled Multiplexer controller.
+
+ The driver builds a single multiplexer controller using a number
+ of gpio pins. For N pins, there will be 2^N possible multiplexer
+ states. The GPIO pins can be connected (by the hardware) to several
+ multiplexers, which in that case will be operated in parallel.
+
+ To compile the driver as a module, choose M here: the module will
+ be called mux-gpio.
+
+endif
diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile
new file mode 100644
index 000000000000..facc43da3648
--- /dev/null
+++ b/drivers/mux/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for multiplexer devices.
+#
+
+obj-$(CONFIG_MULTIPLEXER) += mux-core.o
+obj-$(CONFIG_MUX_GPIO) += mux-gpio.o
diff --git a/drivers/mux/mux-core.c b/drivers/mux/mux-core.c
new file mode 100644
index 000000000000..16a61253d164
--- /dev/null
+++ b/drivers/mux/mux-core.c
@@ -0,0 +1,406 @@
+/*
+ * 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/idr.h>
+#include <linux/module.h>
+#include <linux/mux.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+
+static struct class mux_class = {
+ .name = "mux",
+ .owner = THIS_MODULE,
+};
+
+static int __init mux_init(void)
+{
+ return class_register(&mux_class);
+}
+
+static DEFINE_IDA(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,
+};
+
+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 NULL;
+
+ mux_chip = kzalloc(sizeof(*mux_chip) +
+ controllers * sizeof(*mux_chip->mux) +
+ sizeof_priv, GFP_KERNEL);
+ if (!mux_chip)
+ return NULL;
+
+ 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) {
+ pr_err("muxchipX failed to get a device id\n");
+ kfree(mux_chip);
+ return NULL;
+ }
+ 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;
+ init_rwsem(&mux->lock);
+ mux->cached_state = -1;
+ mux->idle_state = -1;
+ }
+
+ 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 ? -1 : state;
+
+ return ret;
+}
+
+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 mux_chip_register: %d\n", ret);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(mux_chip_register);
+
+void mux_chip_unregister(struct mux_chip *mux_chip)
+{
+ device_del(&mux_chip->dev);
+}
+EXPORT_SYMBOL_GPL(mux_chip_unregister);
+
+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);
+}
+
+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;
+
+ if (WARN_ON(!r || !*r))
+ return 0;
+
+ return *r == data;
+}
+
+void devm_mux_chip_free(struct device *dev, struct mux_chip *mux_chip)
+{
+ WARN_ON(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);
+}
+
+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);
+
+void devm_mux_chip_unregister(struct device *dev, struct mux_chip *mux_chip)
+{
+ WARN_ON(devres_release(dev, devm_mux_chip_reg_release,
+ devm_mux_chip_match, mux_chip));
+}
+EXPORT_SYMBOL_GPL(devm_mux_chip_unregister);
+
+int mux_control_select(struct mux_control *mux, int state)
+{
+ int ret;
+
+ if (down_read_trylock(&mux->lock)) {
+ if (mux->cached_state == state)
+ return 0;
+
+ /* Sigh, the mux needs updating... */
+ up_read(&mux->lock);
+ }
+
+ /* ...or it's just contended. */
+ down_write(&mux->lock);
+
+ if (mux->cached_state == state) {
+ /*
+ * Hmmm, someone else changed the mux to my liking.
+ * That makes me wonder how long I waited for nothing?
+ */
+ downgrade_write(&mux->lock);
+ return 0;
+ }
+
+ ret = mux_control_set(mux, state);
+ if (ret < 0) {
+ if (mux->idle_state != -1)
+ mux_control_set(mux, mux->idle_state);
+
+ up_write(&mux->lock);
+ return ret;
+ }
+
+ downgrade_write(&mux->lock);
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(mux_control_select);
+
+int mux_control_deselect(struct mux_control *mux)
+{
+ int ret = 0;
+
+ if (mux->idle_state != -1 && mux->cached_state != mux->idle_state)
+ ret = mux_control_set(mux, mux->idle_state);
+
+ up_read(&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;
+}
+
+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);
+
+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);
+}
+
+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;
+
+ if (WARN_ON(!r || !*r))
+ return 0;
+
+ return *r == data;
+}
+
+void devm_mux_control_put(struct device *dev, struct mux_control *mux)
+{
+ WARN_ON(devres_release(dev, devm_mux_control_release,
+ devm_mux_control_match, mux));
+}
+EXPORT_SYMBOL_GPL(devm_mux_control_put);
+
+subsys_initcall(mux_init);
+
+MODULE_DESCRIPTION("Multiplexer subsystem");
+MODULE_AUTHOR("Peter Rosin <peda@axentia.se");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/mux/mux-gpio.c b/drivers/mux/mux-gpio.c
new file mode 100644
index 000000000000..48ca4d6b4fc7
--- /dev/null
+++ b/drivers/mux/mux-gpio.c
@@ -0,0 +1,115 @@
+/*
+ * GPIO-controlled 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/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/mux.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 = "mux-gpio", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mux_gpio_dt_ids);
+
+static int mux_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct mux_chip *mux_chip;
+ struct mux_gpio *mux_gpio;
+ int pins;
+ u32 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 (!mux_chip)
+ return -ENOMEM;
+
+ 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", &idle_state);
+ if (ret >= 0) {
+ if (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 = "mux-gpio",
+ .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@axentia.se");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/mux.h b/include/linux/mux.h
new file mode 100644
index 000000000000..ec9e605d8acf
--- /dev/null
+++ b/include/linux/mux.h
@@ -0,0 +1,244 @@
+/*
+ * mux.h - definitions for the multiplexer 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_H
+#define _LINUX_MUX_H
+
+#include <linux/device.h>
+#include <linux/rwsem.h>
+
+struct mux_chip;
+struct mux_control;
+struct platform_device;
+
+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.
+ * @states: The number of mux controller states.
+ * @cached_state: The current mux controller state, or -1 if none.
+ * @idle_state: The mux controller state to use when inactive, or -1
+ * for none.
+ */
+struct mux_control {
+ struct rw_semaphore lock; /* protects the state of the mux */
+
+ struct mux_chip *chip;
+
+ unsigned int states;
+ int cached_state;
+ 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 is 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];
+}
+
+/**
+ * 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.
+ *
+ * Return: A pointer to the new mux-chip, NULL on failure.
+ */
+struct mux_chip *mux_chip_alloc(struct device *dev,
+ unsigned int controllers, size_t sizeof_priv);
+
+/**
+ * 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);
+
+/**
+ * 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);
+
+/**
+ * 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);
+
+/**
+ * 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, NULL on failure.
+ */
+struct mux_chip *devm_mux_chip_alloc(struct device *dev,
+ unsigned int controllers,
+ size_t sizeof_priv);
+
+/**
+ * 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);
+
+/**
+ * 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);
+
+/**
+ * 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);
+
+/**
+ * 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 if the requested state was already active, or 1 it the
+ * mux-control state was changed to the requested state. Or a negavive
+ * errno on error.
+ *
+ * Note that the difference in return value of zero or one is of
+ * questionable value; especially if the mux-control has several independent
+ * consumers, which is something the consumers should perhaps not be making
+ * assumptions about.
+ */
+int mux_control_select(struct mux_control *mux, int state);
+
+/**
+ * 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 for others to access.
+ */
+int mux_control_deselect(struct mux_control *mux);
+
+/**
+ * mux_control_get_index() - Get the index of the given mux controller
+ * @mux: The mux-control to the 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;
+}
+
+/**
+ * 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);
+
+/**
+ * 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);
+
+/**
+ * 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);
+
+/**
+ * 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);
+
+#endif /* _LINUX_MUX_H */
--
2.1.4
^ permalink raw reply related
* [PATCH v8 04/12] iio: inkern: api for manipulating ext_info of iio channels
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-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 b0f4630a163f..4848b8129e6c 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -863,3 +863,63 @@ 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 v8 05/12] dt-bindings: iio: io-channel-mux: document io-channel-mux bindings
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-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>
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 e4fac17e0fa4..35325a3d9ca4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6289,6 +6289,12 @@ 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 v8 06/12] iio: multiplexer: new iio category and iio-mux driver
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-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 | 456 ++++++++++++++++++++++++++++++++++++++
6 files changed, 483 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 35325a3d9ca4..bfbc1a9dd3fe 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6294,6 +6294,7 @@ 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..94d40f9bef4c
--- /dev/null
+++ b/drivers/iio/multiplexer/iio-mux.c
@@ -0,0 +1,456 @@
+/*
+ * 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.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+struct mux_ext_info_cache {
+ char *data;
+ size_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;
+
+ 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) {
+ 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 v8 07/12] dt-bindings: i2c: i2c-mux-simple: document i2c-mux-simple bindings
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-git-send-email-peda@axentia.se>
Describe how a generic multiplexer controller is used to mux an i2c bus.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
.../devicetree/bindings/i2c/i2c-mux-simple.txt | 81 ++++++++++++++++++++++
1 file changed, 81 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt b/Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt
new file mode 100644
index 000000000000..253d5027843b
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-simple.txt
@@ -0,0 +1,81 @@
+Simple 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-simple,mux-locked or i2c-mux-simple,parent-locked
+- 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
+
+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 = "mux-gpio";
+ #mux-control-cells = <0>;
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+ <&pioA 1 GPIO_ACTIVE_HIGH>;
+ };
+
+ i2c-mux {
+ compatible = "i2c-mux-simple,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 v8 08/12] i2c: i2c-mux-simple: new driver
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel-u79uwXL29TY76Z2rM5mHXA
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton,
linux-i2c-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-iio-u79uwXL29TY76Z2rM5mHXA,
linux-doc-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <1484755035-25927-1-git-send-email-peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
This is a generic simple i2c mux that uses the generic 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-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Acked-by: Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>
Signed-off-by: Peter Rosin <peda-koto5C5qi+TLoDKTGw+V6w@public.gmane.org>
---
drivers/i2c/muxes/Kconfig | 13 +++
drivers/i2c/muxes/Makefile | 1 +
drivers/i2c/muxes/i2c-mux-simple.c | 182 +++++++++++++++++++++++++++++++++++++
3 files changed, 196 insertions(+)
create mode 100644 drivers/i2c/muxes/i2c-mux-simple.c
diff --git a/drivers/i2c/muxes/Kconfig b/drivers/i2c/muxes/Kconfig
index 10b3d17ae3ea..565921e09a96 100644
--- a/drivers/i2c/muxes/Kconfig
+++ b/drivers/i2c/muxes/Kconfig
@@ -73,6 +73,19 @@ config I2C_MUX_REG
This driver can also be built as a module. If so, the module
will be called i2c-mux-reg.
+config I2C_MUX_SIMPLE
+ tristate "Simple I2C multiplexer"
+ select MULTIPLEXER
+ depends on OF
+ help
+ If you say yes to this option, support will be included for a
+ simple generic I2C multiplexer. This driver provides access to
+ I2C busses connected through a MUX, which is controlled
+ by a generic MUX controller.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-mux-simple.
+
config I2C_DEMUX_PINCTRL
tristate "pinctrl-based I2C demultiplexer"
depends on PINCTRL && OF
diff --git a/drivers/i2c/muxes/Makefile b/drivers/i2c/muxes/Makefile
index 9948fa45037f..6821d95c92a3 100644
--- a/drivers/i2c/muxes/Makefile
+++ b/drivers/i2c/muxes/Makefile
@@ -11,5 +11,6 @@ obj-$(CONFIG_I2C_MUX_PCA9541) += i2c-mux-pca9541.o
obj-$(CONFIG_I2C_MUX_PCA954x) += i2c-mux-pca954x.o
obj-$(CONFIG_I2C_MUX_PINCTRL) += i2c-mux-pinctrl.o
obj-$(CONFIG_I2C_MUX_REG) += i2c-mux-reg.o
+obj-$(CONFIG_I2C_MUX_SIMPLE) += i2c-mux-simple.o
ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG
diff --git a/drivers/i2c/muxes/i2c-mux-simple.c b/drivers/i2c/muxes/i2c-mux-simple.c
new file mode 100644
index 000000000000..6a7de6e91ae3
--- /dev/null
+++ b/drivers/i2c/muxes/i2c-mux-simple.c
@@ -0,0 +1,182 @@
+/*
+ * Generic simple I2C multiplexer
+ *
+ * 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/i2c.h>
+#include <linux/i2c-mux.h>
+#include <linux/module.h>
+#include <linux/mux.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+
+#define SIMPLE_PARENT_LOCKED (0)
+#define SIMPLE_MUX_LOCKED (1)
+
+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-simple,parent-locked",
+ .data = (void *)SIMPLE_PARENT_LOCKED, },
+ { .compatible = "i2c-mux-simple,mux-locked",
+ .data = (void *)SIMPLE_MUX_LOCKED, },
+ {},
+};
+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;
+ const struct of_device_id *match;
+ 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);
+
+ match = of_match_device(of_match_ptr(i2c_mux_of_match), dev);
+ if (match)
+ muxc->mux_locked = !!of_device_get_match_data(dev);
+
+ 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) {
+ 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-simple",
+ .of_match_table = i2c_mux_of_match,
+ },
+};
+module_platform_driver(i2c_mux_driver);
+
+MODULE_DESCRIPTION("Simple I2C 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 v8 09/12] dt-bindings: mux-adg792a: document devicetree bindings for ADG792A/G mux
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-git-send-email-peda@axentia.se>
Analog Devices ADG792A/G is a triple 4:1 mux.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
.../devicetree/bindings/mux/mux-adg792a.txt | 79 ++++++++++++++++++++++
1 file changed, 79 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mux/mux-adg792a.txt
diff --git a/Documentation/devicetree/bindings/mux/mux-adg792a.txt b/Documentation/devicetree/bindings/mux/mux-adg792a.txt
new file mode 100644
index 000000000000..0b26dd11f070
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/mux-adg792a.txt
@@ -0,0 +1,79 @@
+Bindings for Analog Devices ADG792A/G Triple 4:1 Multiplexers
+
+Required properties:
+- compatible : "adi,adg792a" or "adi,adg792g"
+- #mux-control-cells : <0> if parallel, or <1> if not.
+* Standard mux-controller bindings as decribed 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:
+- adi,parallel : if present, the three muxes are bound together with a single
+ mux controller, controlling all three muxes in parallel.
+- adi,idle-state : if present, array of 2-tuples with mux controller number
+ and state that mux controllers will have when idle. States 0 through 3
+ correspond to signals A through D in the datasheet.
+- adi,idle-high-impedance : if present, array of mux controller numbers that
+ should be in the disconnected high-impedance state when idle.
+
+Mux controller states 0 through 3 correspond to signals A through D in the
+datasheet. If a mux controller is mentioned in neither adi,idle-state nor
+adi,idle-high-impedance it is left in its previously selected state when idle.
+
+Example:
+
+ /*
+ * Three independent mux controllers (of which one is used).
+ * Mux 0 is disconnected when idle, mux 1 idles with signal C
+ * and mux 2 idles with signal A.
+ */
+ &i2c0 {
+ mux: adg792a@50 {
+ compatible = "adi,adg792a";
+ reg = <0x50>;
+ #mux-control-cells = <1>;
+
+ adi,idle-high-impedance = <0>;
+ adi,idle-state = <1 2>, <2 0>;
+ };
+ };
+
+ adc-mux {
+ compatible = "io-channel-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ mux-controls = <&mux 1>;
+
+ 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: adg792a@50 {
+ compatible = "adi,adg792a";
+ reg = <0x50>;
+ #mux-control-cells = <0>;
+ adi,parallel;
+ };
+ };
+
+ 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
* [PATCH v8 10/12] mux: adg792a: add mux controller driver for ADG792A/G
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-git-send-email-peda@axentia.se>
Analog Devices ADG792A/G is a triple 4:1 mux.
Reviewed-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/mux/Kconfig | 12 ++++
drivers/mux/Makefile | 1 +
drivers/mux/mux-adg792a.c | 167 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 180 insertions(+)
create mode 100644 drivers/mux/mux-adg792a.c
diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
index 57e6f4e5fda9..d13fcf98958e 100644
--- a/drivers/mux/Kconfig
+++ b/drivers/mux/Kconfig
@@ -16,6 +16,18 @@ menuconfig MULTIPLEXER
if MULTIPLEXER
+config MUX_ADG792A
+ tristate "Analog Devices ADG792A/ADG792G Multiplexers"
+ depends on I2C
+ help
+ ADG792A and ADG792G Wide Bandwidth Triple 4:1 Multiplexers
+
+ The driver supports both operating the three multiplexers in
+ parallel and operating them independently.
+
+ To compile the driver as a module, choose M here: the module will
+ be called mux-adg792a.
+
config MUX_GPIO
tristate "GPIO-controlled Multiplexer"
depends on OF && GPIOLIB
diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile
index facc43da3648..fddbb073fc77 100644
--- a/drivers/mux/Makefile
+++ b/drivers/mux/Makefile
@@ -3,4 +3,5 @@
#
obj-$(CONFIG_MULTIPLEXER) += mux-core.o
+obj-$(CONFIG_MUX_ADG792A) += mux-adg792a.o
obj-$(CONFIG_MUX_GPIO) += mux-gpio.o
diff --git a/drivers/mux/mux-adg792a.c b/drivers/mux/mux-adg792a.c
new file mode 100644
index 000000000000..6a4c4c9f585b
--- /dev/null
+++ b/drivers/mux/mux-adg792a.c
@@ -0,0 +1,167 @@
+/*
+ * Multiplexer driver for Analog Devices ADG792A/G Triple 4:1 mux
+ *
+ * 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/i2c.h>
+#include <linux/module.h>
+#include <linux/mux.h>
+
+#define ADG792A_LDSW BIT(0)
+#define ADG792A_RESET BIT(1)
+#define ADG792A_DISABLE(mux) (0x50 | (mux))
+#define ADG792A_DISABLE_ALL (0x5f)
+#define ADG792A_MUX(mux, state) (0xc0 | (((mux) + 1) << 2) | (state))
+#define ADG792A_MUX_ALL(state) (0xc0 | (state))
+
+#define ADG792A_DISABLE_STATE (4)
+
+static int adg792a_set(struct mux_control *mux, int state)
+{
+ struct i2c_client *i2c = to_i2c_client(mux->chip->dev.parent);
+ u8 cmd;
+
+ if (mux->chip->controllers == 1) {
+ /* parallel mux controller operation */
+ if (state == ADG792A_DISABLE_STATE)
+ cmd = ADG792A_DISABLE_ALL;
+ else
+ cmd = ADG792A_MUX_ALL(state);
+ } else {
+ unsigned int controller = mux_control_get_index(mux);
+
+ if (state == ADG792A_DISABLE_STATE)
+ cmd = ADG792A_DISABLE(controller);
+ else
+ cmd = ADG792A_MUX(controller, state);
+ }
+
+ return i2c_smbus_write_byte_data(i2c, cmd, ADG792A_LDSW);
+}
+
+static const struct mux_control_ops adg792a_ops = {
+ .set = adg792a_set,
+};
+
+static int adg792a_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ struct device *dev = &i2c->dev;
+ struct mux_chip *mux_chip;
+ bool parallel;
+ int count;
+ int ret;
+ int i;
+
+ parallel = of_property_read_bool(i2c->dev.of_node, "adi,parallel");
+
+ mux_chip = devm_mux_chip_alloc(dev, parallel ? 1 : 3, 0);
+ if (!mux_chip)
+ return -ENOMEM;
+
+ mux_chip->ops = &adg792a_ops;
+
+ ret = i2c_smbus_write_byte_data(i2c, ADG792A_DISABLE_ALL,
+ ADG792A_RESET | ADG792A_LDSW);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < mux_chip->controllers; ++i) {
+ struct mux_control *mux = &mux_chip->mux[i];
+
+ mux->states = 4;
+ }
+
+ count = of_property_count_u32_elems(dev->of_node, "adi,idle-state");
+ for (i = 0; i < count; i += 2) {
+ u32 index;
+ u32 idle_state;
+
+ ret = of_property_read_u32_index(dev->of_node,
+ "adi,idle-state", i,
+ &index);
+ if (ret < 0)
+ return ret;
+ if (index >= mux_chip->controllers) {
+ dev_err(dev, "invalid mux %u\n", index);
+ return -EINVAL;
+ }
+
+ ret = of_property_read_u32_index(dev->of_node,
+ "adi,idle-state", i + 1,
+ &idle_state);
+ if (ret < 0)
+ return ret;
+ if (idle_state >= ADG792A_DISABLE_STATE) {
+ dev_err(dev, "invalid idle-state %u for mux %u\n",
+ idle_state, index);
+ return -EINVAL;
+ }
+ mux_chip->mux[index].idle_state = idle_state;
+ }
+
+ count = of_property_count_u32_elems(dev->of_node,
+ "adi,idle-high-impedance");
+ for (i = 0; i < count; ++i) {
+ u32 index;
+
+ ret = of_property_read_u32_index(dev->of_node,
+ "adi,idle-high-impedance", i,
+ &index);
+ if (ret < 0)
+ return ret;
+ if (index >= mux_chip->controllers) {
+ dev_err(dev, "invalid mux %u\n", index);
+ return -EINVAL;
+ }
+
+ mux_chip->mux[index].idle_state = ADG792A_DISABLE_STATE;
+ }
+
+ ret = devm_mux_chip_register(dev, mux_chip);
+ if (ret < 0)
+ return ret;
+
+ if (parallel)
+ dev_info(dev, "triple pole quadruple throw mux registered\n");
+ else
+ dev_info(dev, "3x single pole quadruple throw muxes registered\n");
+
+ return 0;
+}
+
+static const struct i2c_device_id adg792a_id[] = {
+ { .name = "adg792a", },
+ { .name = "adg792g", },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, adg792a_id);
+
+static const struct of_device_id adg792a_of_match[] = {
+ { .compatible = "adi,adg792a", },
+ { .compatible = "adi,adg792g", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, adg792a_of_match);
+
+static struct i2c_driver adg792a_driver = {
+ .driver = {
+ .name = "adg792a",
+ .of_match_table = of_match_ptr(adg792a_of_match),
+ },
+ .probe = adg792a_probe,
+ .id_table = adg792a_id,
+};
+module_i2c_driver(adg792a_driver);
+
+MODULE_DESCRIPTION("Analog Devices ADG792A/G Triple 4:1 mux driver");
+MODULE_AUTHOR("Peter Rosin <peda@axentia.se");
+MODULE_LICENSE("GPL v2");
--
2.1.4
^ permalink raw reply related
* [PATCH v8 11/12] dt-bindings: simplified bindings for single-user gpio mux
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-git-send-email-peda@axentia.se>
Allow bindings for a GPIO controlled mux to be specified in the
mux consumer node.
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Peter Rosin <peda@axentia.se>
---
.../devicetree/bindings/mux/mux-controller.txt | 26 ++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/Documentation/devicetree/bindings/mux/mux-controller.txt b/Documentation/devicetree/bindings/mux/mux-controller.txt
index 42b2177e5ae1..4e89df8b2392 100644
--- a/Documentation/devicetree/bindings/mux/mux-controller.txt
+++ b/Documentation/devicetree/bindings/mux/mux-controller.txt
@@ -125,3 +125,29 @@ An example mux controller might look like this:
reg = <0x50>;
#mux-control-cells = <1>;
};
+
+
+Combinded controller and consumer of a GPIO mux
+-----------------------------------------------
+
+For the common case of a single consumer of a GPIO controlled mux, there is
+a simplified binding which will instantiate an implicit mux controller. Just
+specify a mux-gpios property with the same interpretation as in mux-gpio.txt.
+Note that other properties described in mux-gpio.txt are not available in
+this simplified form and that the mux controller is unnamed. If you need
+more than one mux controller, a shared mux controller or if you need a
+specific idle-state, use the more flexible binding with the mux controller
+in its own node.
+
+Example:
+
+ adc-mux {
+ compatible = "io-channel-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+ <&pioA 1 GPIO_ACTIVE_HIGH>;
+
+ channels = "sync-1", "in", "out", "sync-2";
+ };
--
2.1.4
^ permalink raw reply related
* [PATCH v8 12/12] mux: support simplified bindings for single-user gpio mux
From: Peter Rosin @ 2017-01-18 15:57 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Rosin, Wolfram Sang, Rob Herring, Mark Rutland,
Jonathan Cameron, Hartmut Knaack, Lars-Peter Clausen,
Peter Meerwald-Stadler, Jonathan Corbet, Andrew Morton, linux-i2c,
devicetree, linux-iio, linux-doc
In-Reply-To: <1484755035-25927-1-git-send-email-peda@axentia.se>
Allow bindings for a GPIO controlled mux to be specified in the
mux consumer node.
Signed-off-by: Peter Rosin <peda@axentia.se>
---
drivers/mux/Kconfig | 5 +----
drivers/mux/mux-core.c | 23 +++++++++++++++++++++--
drivers/mux/mux-gpio.c | 28 +++++++++++++++++++++-------
drivers/mux/mux-gpio.h | 13 +++++++++++++
4 files changed, 56 insertions(+), 13 deletions(-)
create mode 100644 drivers/mux/mux-gpio.h
diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
index d13fcf98958e..cd161c228537 100644
--- a/drivers/mux/Kconfig
+++ b/drivers/mux/Kconfig
@@ -29,7 +29,7 @@ config MUX_ADG792A
be called mux-adg792a.
config MUX_GPIO
- tristate "GPIO-controlled Multiplexer"
+ bool "GPIO-controlled Multiplexer"
depends on OF && GPIOLIB
help
GPIO-controlled Multiplexer controller.
@@ -39,7 +39,4 @@ config MUX_GPIO
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/mux-core.c b/drivers/mux/mux-core.c
index 16a61253d164..0caafd6f5a77 100644
--- a/drivers/mux/mux-core.c
+++ b/drivers/mux/mux-core.c
@@ -21,6 +21,8 @@
#include <linux/of_platform.h>
#include <linux/slab.h>
+#include "mux-gpio.h"
+
static struct class mux_class = {
.name = "mux",
.owner = THIS_MODULE,
@@ -314,9 +316,26 @@ struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
ret = of_parse_phandle_with_args(np,
"mux-controls", "#mux-control-cells",
index, &args);
+
+#ifdef CONFIG_MUX_GPIO
+ if (ret == -ENOENT && !mux_name) {
+ mux_chip = mux_gpio_alloc(dev);
+ if (!IS_ERR(mux_chip)) {
+ ret = devm_mux_chip_register(dev, mux_chip);
+ if (ret < 0)
+ return ERR_PTR(ret);
+ get_device(&mux_chip->dev);
+ return mux_chip->mux;
+ }
+
+ ret = PTR_ERR(mux_chip);
+ }
+#endif
+
if (ret) {
- dev_err(dev, "%s: failed to get mux-control %s(%i)\n",
- np->full_name, mux_name ?: "", index);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "%s: failed to get mux-control %s(%i)\n",
+ np->full_name, mux_name ?: "", index);
return ERR_PTR(ret);
}
diff --git a/drivers/mux/mux-gpio.c b/drivers/mux/mux-gpio.c
index 48ca4d6b4fc7..2ab8735e3415 100644
--- a/drivers/mux/mux-gpio.c
+++ b/drivers/mux/mux-gpio.c
@@ -18,6 +18,8 @@
#include <linux/platform_device.h>
#include <linux/property.h>
+#include "mux-gpio.h"
+
struct mux_gpio {
struct gpio_descs *gpios;
int *val;
@@ -48,24 +50,21 @@ static const struct of_device_id mux_gpio_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, mux_gpio_dt_ids);
-static int mux_gpio_probe(struct platform_device *pdev)
+struct mux_chip *mux_gpio_alloc(struct device *dev)
{
- struct device *dev = &pdev->dev;
- struct device_node *np = dev->of_node;
struct mux_chip *mux_chip;
struct mux_gpio *mux_gpio;
int pins;
- u32 idle_state;
int ret;
pins = gpiod_count(dev, "mux");
if (pins < 0)
- return pins;
+ return ERR_PTR(pins);
mux_chip = devm_mux_chip_alloc(dev, 1, sizeof(*mux_gpio) +
pins * sizeof(*mux_gpio->val));
if (!mux_chip)
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
mux_gpio = mux_chip_priv(mux_chip);
mux_gpio->val = (int *)(mux_gpio + 1);
@@ -76,11 +75,26 @@ static int mux_gpio_probe(struct platform_device *pdev)
ret = PTR_ERR(mux_gpio->gpios);
if (ret != -EPROBE_DEFER)
dev_err(dev, "failed to get gpios\n");
- return ret;
+ return ERR_PTR(ret);
}
WARN_ON(pins != mux_gpio->gpios->ndescs);
mux_chip->mux->states = 1 << pins;
+ return mux_chip;
+}
+EXPORT_SYMBOL_GPL(mux_gpio_alloc);
+
+static int mux_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mux_chip *mux_chip;
+ u32 idle_state;
+ int ret;
+
+ mux_chip = mux_gpio_alloc(dev);
+ if (IS_ERR(mux_chip))
+ return PTR_ERR(mux_chip);
+
ret = device_property_read_u32(dev, "idle-state", &idle_state);
if (ret >= 0) {
if (idle_state >= mux_chip->mux->states) {
diff --git a/drivers/mux/mux-gpio.h b/drivers/mux/mux-gpio.h
new file mode 100644
index 000000000000..fe3e8d0173aa
--- /dev/null
+++ b/drivers/mux/mux-gpio.h
@@ -0,0 +1,13 @@
+/*
+ * GPIO-controlled 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.
+ */
+
+struct mux_chip *mux_gpio_alloc(struct device *dev);
--
2.1.4
^ permalink raw reply related
* Re: [PATCH v3] arm64: dts: exynos: Remove unneeded unit names in Exynos5433 nodes
From: Krzysztof Kozlowski @ 2017-01-18 16:27 UTC (permalink / raw)
To: Javier Martinez Canillas
Cc: linux-kernel, Andi Shyti, Pankaj Dubey, Chanwoo Choi, devicetree,
Kukjin Kim, Catalin Marinas, linux-samsung-soc, Rob Herring,
Will Deacon, Mark Rutland, Krzysztof Kozlowski, linux-arm-kernel
In-Reply-To: <1484754613-2425-1-git-send-email-javier@osg.samsung.com>
On Wed, Jan 18, 2017 at 12:50:13PM -0300, Javier Martinez Canillas wrote:
> The "samsung,exynos5433-mipi-video-phy" and "samsung,exynos5250-dwusb3"
> DT bindings don't specify a reg property for these nodes, so having a
> unit name leads to the following DTC warnings:
>
> Node /soc/video-phy@105c0710 has a unit name, but no reg property
> Node /soc/usb@15400000 has a unit name, but no reg property
> Node /soc/usb@15a00000 has a unit name, but no reg property
>
> Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
>
> ---
>
> Changes in v3:
> - Use proper device node names, suggested by Krzysztof.
>
> Changes in v2:
> - Fix subject line since I forgot the "exynos" prefix.
>
> arch/arm64/boot/dts/exynos/exynos5433.dtsi | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
Thanks, applied.
Best regards,
Krzysztof
^ permalink raw reply
* Re: [PATCH v14 3/5] tee: add OP-TEE driver
From: Arnd Bergmann @ 2017-01-18 16:28 UTC (permalink / raw)
To: Jens Wiklander
Cc: valentin.manea, devicetree, javier, emmanuel.michel,
scott.branden, Nishanth Menon, Greg Kroah-Hartman, broonie,
Mark Rutland, Will Deacon, linux-kernel, Wei Xu,
jean-michel.delorme, Jason Gunthorpe, Rob Herring, Al Viro,
Olof Johansson, Andrew Morton, Andrew F . Davis, Michal Simek,
linux-arm-kernel
In-Reply-To: <1484744296-30003-4-git-send-email-jens.wiklander@linaro.org>
On Wednesday, January 18, 2017 1:58:14 PM CET Jens Wiklander wrote:
> Adds a OP-TEE driver which also can be compiled as a loadable module.
>
> * Targets ARM and ARM64
> * Supports using reserved memory from OP-TEE as shared memory
> * Probes OP-TEE version using SMCs
> * Accepts requests on privileged and unprivileged device
> * Uses OPTEE message protocol version 2 to communicate with secure world
I had not really followed the last versions, and I've looked through
it now for things that seemed odd to me, either because I don't understand
them or because they could be improved. I'll try to read it again after
I've seen clarifications on these points.
Generally speaking I haven't seen any show-stoppers so far.
> +struct optee_call_waiter {
> + struct list_head list_node;
> + struct completion c;
> + bool completed;
> +};
It seems wrong to have both a 'struct completion' and 'bool completed' here,
as completion already contains such a flag and is designed to update that
atomically.
> +static void optee_cq_complete_one(struct optee_call_queue *cq)
> +{
> + struct optee_call_waiter *w;
> +
> + list_for_each_entry(w, &cq->waiters, list_node) {
> + if (!w->completed) {
> + complete(&w->c);
> + w->completed = true;
> + break;
> + }
> + }
> +}
> +
> +static void optee_cq_wait_final(struct optee_call_queue *cq,
> + struct optee_call_waiter *w)
> +{
> + mutex_lock(&cq->mutex);
> +
> + /* Get out of the list */
> + list_del(&w->list_node);
> +
> + optee_cq_complete_one(cq);
> + /*
> + * If we're completed we've got a completion that some other task
> + * could have used instead.
> + */
> + if (w->completed)
> + optee_cq_complete_one(cq);
> +
> + mutex_unlock(&cq->mutex);
> +}
This deserves some more comments: the function name suggests that you are
waiting for a specific optee_call_waiter, but then it calls
optee_cq_complete_one(), which unconditionally completes the first
incomplete completion and it never waits.
> +static struct tee_shm_pool *
> +optee_config_shm_ioremap(struct device *dev, optee_invoke_fn *invoke_fn,
> + void __iomem **ioremaped_shm)
> +{
> + union {
> + struct arm_smccc_res smccc;
> + struct optee_smc_get_shm_config_result result;
> + } res;
> + struct tee_shm_pool *pool;
> + unsigned long vaddr;
> + phys_addr_t paddr;
> + size_t size;
> + phys_addr_t begin;
> + phys_addr_t end;
> + void __iomem *va;
> + struct tee_shm_pool_mem_info priv_info;
> + struct tee_shm_pool_mem_info dmabuf_info;
> +
> + invoke_fn(OPTEE_SMC_GET_SHM_CONFIG, 0, 0, 0, 0, 0, 0, 0, &res.smccc);
> + if (res.result.status != OPTEE_SMC_RETURN_OK) {
> + dev_info(dev, "shm service not available\n");
> + return ERR_PTR(-ENOENT);
> + }
> +
> + if (res.result.settings != OPTEE_SMC_SHM_CACHED) {
> + dev_err(dev, "only normal cached shared memory supported\n");
> + return ERR_PTR(-EINVAL);
> + }
> +
> + begin = roundup(res.result.start, PAGE_SIZE);
> + end = rounddown(res.result.start + res.result.size, PAGE_SIZE);
> + paddr = begin;
> + size = end - begin;
> +
> + if (size < 2 * OPTEE_SHM_NUM_PRIV_PAGES * PAGE_SIZE) {
> + dev_err(dev, "too small shared memory area\n");
> + return ERR_PTR(-EINVAL);
> + }
> +
> + va = ioremap_cache(paddr, size);
> + if (!va) {
> + dev_err(dev, "shared memory ioremap failed\n");
> + return ERR_PTR(-EINVAL);
> + }
> + vaddr = (unsigned long)va;
I think you should call memremap() instead of ioremap_cache() here and assume
that you are talking to actual RAM.
> +static int __init optee_driver_init(void)
> +{
> + struct device_node *node;
> +
> + /*
> + * Preferred path is /firmware/optee, but it's the matching that
> + * matters.
> + */
> + for_each_matching_node(node, optee_match)
> + of_platform_device_create(node, NULL, NULL);
> +
> + return platform_driver_register(&optee_driver);
> +}
> +module_init(optee_driver_init);
> +
> +static void __exit optee_driver_exit(void)
> +{
> + platform_driver_unregister(&optee_driver);
> +}
> +module_exit(optee_driver_exit);
What is the platform driver good for if the same module has to create the
platform devices itself?
I'd just skip it and do
for_each_matching_node(node, optee_match)
optee_probe(node);
I also suspect that module unloading is broken here if you don't clean
up the platform devices in the end, so you should already remove the
exit function to prevent unloading.
> +struct optee_msg_arg {
> + u32 cmd;
> + u32 func;
> + u32 session;
> + u32 cancel_id;
> + u32 pad;
> + u32 ret;
> + u32 ret_origin;
> + u32 num_params;
> +
> + /*
> + * this struct is 8 byte aligned since the 'struct optee_msg_param'
> + * which follows requires 8 byte alignment.
> + *
> + * Commented out element used to visualize the layout dynamic part
> + * of the struct. This field is not available at all if
> + * num_params == 0.
> + *
> + * params is accessed through the macro OPTEE_MSG_GET_PARAMS
> + *
> + * struct optee_msg_param params[num_params];
> + */
> +} __aligned(8);
> +
> +/**
> + * OPTEE_MSG_GET_PARAMS - return pointer to struct optee_msg_param *
> + *
> + * @x: Pointer to a struct optee_msg_arg
> + *
> + * Returns a pointer to the params[] inside a struct optee_msg_arg.
> + */
> +#define OPTEE_MSG_GET_PARAMS(x) \
> + (struct optee_msg_param *)(((struct optee_msg_arg *)(x)) + 1)
If you make the last member of optee_msg_arg
struct optee_msg_param params[0];
then you can remove both the macro here and the alignment attribute.
> +/*****************************************************************************
> + * Part 2 - requests from normal world
> + *****************************************************************************/
> +
> +/*
> + * Return the following UID if using API specified in this file without
> + * further extensions:
> + * 384fb3e0-e7f8-11e3-af63-0002a5d5c51b.
> + * Represented in 4 32-bit words in OPTEE_MSG_UID_0, OPTEE_MSG_UID_1,
> + * OPTEE_MSG_UID_2, OPTEE_MSG_UID_3.
> + */
> +#define OPTEE_MSG_UID_0 0x384fb3e0
> +#define OPTEE_MSG_UID_1 0xe7f811e3
> +#define OPTEE_MSG_UID_2 0xaf630002
> +#define OPTEE_MSG_UID_3 0xa5d5c51b
> +#define OPTEE_MSG_FUNCID_CALLS_UID 0xFF01
> +
> +/*
> + * Returns 2.0 if using API specified in this file without further
> + * extensions. Represented in 2 32-bit words in OPTEE_MSG_REVISION_MAJOR
> + * and OPTEE_MSG_REVISION_MINOR
> + */
> +#define OPTEE_MSG_REVISION_MAJOR 2
> +#define OPTEE_MSG_REVISION_MINOR 0
> +#define OPTEE_MSG_FUNCID_CALLS_REVISION 0xFF03
> +
> +/*
> + * Get UUID of Trusted OS.
> + *
> + * Used by non-secure world to figure out which Trusted OS is installed.
> + * Note that returned UUID is the UUID of the Trusted OS, not of the API.
> + *
> + * Returns UUID in 4 32-bit words in the same way as
> + * OPTEE_MSG_FUNCID_CALLS_UID described above.
> + */
> +#define OPTEE_MSG_OS_OPTEE_UUID_0 0x486178e0
> +#define OPTEE_MSG_OS_OPTEE_UUID_1 0xe7f811e3
> +#define OPTEE_MSG_OS_OPTEE_UUID_2 0xbc5e0002
> +#define OPTEE_MSG_OS_OPTEE_UUID_3 0xa5d5c51b
> +#define OPTEE_MSG_FUNCID_GET_OS_UUID 0x0000
> +
> +/*
> + * Get revision of Trusted OS.
> + *
> + * Used by non-secure world to figure out which version of the Trusted OS
> + * is installed. Note that the returned revision is the revision of the
> + * Trusted OS, not of the API.
> + *
> + * Returns revision in 2 32-bit words in the same way as
> + * OPTEE_MSG_CALLS_REVISION described above.
> + */
> +#define OPTEE_MSG_OS_OPTEE_REVISION_MAJOR 1
> +#define OPTEE_MSG_OS_OPTEE_REVISION_MINOR 0
> +#define OPTEE_MSG_FUNCID_GET_OS_REVISION 0x0001
Just for my understanding, what is the significance of these numbers,
i.e. which code (user space, kernel driver, trusted OS) provides
the uuid and which one provides the version? The code comments almost
make sense to me, but I don't see why specific versions are listed
in this header.
What is the expected behavior when one side reports a version that
is unknown? Can one side claim to be backwards compatible with
a previous version, or does each new version need support on
all three sides?
> diff --git a/drivers/tee/optee/rpc.c b/drivers/tee/optee/rpc.c
> new file mode 100644
> index 000000000000..0b9c1a2accd0
> --- /dev/null
> +++ b/drivers/tee/optee/rpc.c
> +static void handle_rpc_func_cmd_wq(struct optee *optee,
> + struct optee_msg_arg *arg)
> +{
> + struct optee_msg_param *params;
> +
> + if (arg->num_params != 1)
> + goto bad;
> +
> + params = OPTEE_MSG_GET_PARAMS(arg);
> + if ((params->attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
> + OPTEE_MSG_ATTR_TYPE_VALUE_INPUT)
> + goto bad;
> +
> + switch (params->u.value.a) {
> + case OPTEE_MSG_RPC_WAIT_QUEUE_SLEEP:
> + wq_sleep(&optee->wait_queue, params->u.value.b);
> + break;
> + case OPTEE_MSG_RPC_WAIT_QUEUE_WAKEUP:
> + wq_wakeup(&optee->wait_queue, params->u.value.b);
> + break;
> + default:
> + goto bad;
> + }
> +
> + arg->ret = TEEC_SUCCESS;
> + return;
> +bad:
> + arg->ret = TEEC_ERROR_BAD_PARAMETERS;
> +}
> +
I'm trying to understand what this is good for. What I can see is that
you have a user space process calling into the kernel asking the tee
to do some command, and then the tee can ask the kernel to wait for
something to happen, or notify it that something has happened.
If we wait here, the user process gets suspended until this has
actually happened.
Am I reading this correctly? If yes, what is the intended use case?
Is there some process that is meant to always wait here? What
if we ever need to wait for more than one thing at a time (think
select or poll?)
> + params = OPTEE_MSG_GET_PARAMS(arg);
> + if ((params->attr & OPTEE_MSG_ATTR_TYPE_MASK) !=
> + OPTEE_MSG_ATTR_TYPE_VALUE_INPUT)
> + goto bad;
> +
> + msec_to_wait = params->u.value.a;
> +
> + /* set task's state to interruptible sleep */
> + set_current_state(TASK_INTERRUPTIBLE);
> +
> + /* take a nap */
> + schedule_timeout(msecs_to_jiffies(msec_to_wait));
This can be done simpler with msleep();
Arnd
^ permalink raw reply
* [PATCH v5 0/2] iio: adc: Add Maxim MAX11100 driver
From: Jacopo Mondi @ 2017-01-18 16:30 UTC (permalink / raw)
To: wsa+renesas-jBu1N2QxHDJrcw3mvpCnnVaTQe2KTcn/,
magnus.damm-Re5JQEeQqe8AvxtiuMwx3w, jic23-DgEjT+Ai2ygdnm+yROfE0A,
knaack.h-Mmb7MZpHnFY, lars-Qo5EllUWu/uELgA04lAiVw,
pmeerw-jW+XmwGofnusTnJN9+BGXg, marek.vasut-Re5JQEeQqe8AvxtiuMwx3w,
geert-Td1EMuHUCqxL1ZNQvxDV9g, robh+dt-DgEjT+Ai2ygdnm+yROfE0A,
mark.rutland-5wv7dgnIgG8
Cc: linux-iio-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA,
linux-renesas-soc-u79uwXL29TY76Z2rM5mHXA
Hello everyone,
hopefully we have reached last iteration on this simple driver.
After having clarified the read_raw() measure unit question, I'm now sending
out v5 addressing Jonathan's comment on having spi destination aligned to
their own cache lines to support DMA-capable SPI controllers.
Also, I added indio_dev->name attribute, as suggested by Lars-Peter even if
the same value can be retrieved from of_node/name.
v1 -> v2:
- incorporated pmeerw's review comments
- retrieve vref from dts and use that to convert read_raw result
to mV
- add device tree bindings documentation
v2 -> v3:
- add _SCALE bit of read_raw function and change _RAW bit accordingly
- call regulator_get_voltage when accessing the _SCALE part of read_raw
and not during probe
- add back remove function as regulator has to be disabled when detaching
the module. Do not use devm_ version of iio_register/unregister functions
anymore but do unregister in the remove.
- remove mutex as access to SPI bus is protected by SPI core. Thanks marex
v3 -> v4:
- split device tree binding documentation and actual ADC driver
- add "reg" to the list of required properties and use a better
namimg for the adc device node in bindings documentation as suggested
by Geert.
v4 -> v5:
- make spi_read() destination buffer cacheline aligned
- add indio_dev->name attribute.
Jacopo Mondi (2):
iio: adc: Add Maxim MAX11100 driver
dt-bindings: iio: document MAX11100 ADC
.../devicetree/bindings/iio/adc/max11100.txt | 19 ++
drivers/iio/adc/Kconfig | 9 +
drivers/iio/adc/Makefile | 1 +
drivers/iio/adc/max11100.c | 192 +++++++++++++++++++++
4 files changed, 221 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/max11100.txt
create mode 100644 drivers/iio/adc/max11100.c
--
2.7.4
^ permalink raw reply
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