RE: [PATCH v4] extcon: gpio: Add the support for Device tree bindings
From: Venkat Reddy Talla
Date: Fri May 27 2016 - 01:13:43 EST
Hi Choi,
Sorry for changing author, will update author field with your name.
Regarding Rob Herring comments, You had already replied.
I felt separate compatible for each external connector is not required,
as client driver can detect the type of external cable(sdp,dcp, microphone) on receiving notification from extcon provider,
I have also added more description for wakeup-source.
Do you see any other changes required on top of v4 patch?
Regards,
Venkat
> -----Original Message-----
> From: Chanwoo Choi [mailto:cwchoi00@xxxxxxxxx]
> Sent: Thursday, May 26, 2016 6:52 PM
> To: Venkat Reddy Talla
> Cc: MyungJoo Ham; Rob Herring; Pawel Moll; Mark Rutland; Ian Campbell;
> devicetree; Kumar Gala; linux-kernel; Laxman Dewangan
> Subject: Re: [PATCH v4] extcon: gpio: Add the support for Device tree
> bindings
>
> Hi Venkat,
>
> There is some miscommunication. On previous my reply, I don't mean that
> the author of the patch[1] is changed from me to you.
>
> I'd like you to remain the original author(me) for the patch[1] without
> changing the author.
> [1] https://lkml.org/lkml/2015/10/21/8
> - [PATCH v3] extcon: gpio: Add the support for Device tree bindings
>
> You can use the patch[1] as based patch and you can add new feature on
> base patch[1]. Also, If you ok, you can modify the extccon-gpio.c driver as
> Rob comment[2].
>
> But, Rob Herring gave me the some comment[2].
> [2] https://lkml.org/lkml/2015/10/21/906
>
>
> Thanks,
> Chanwoo Choi
>
>
> On Thu, May 26, 2016 at 8:47 PM, Venkat Reddy Talla
> <vreddytalla@xxxxxxxxxx> wrote:
> > Add the support for Device tree bindings of extcon-gpio driver.
> > The extcon-gpio device tree node must include the both 'extcon-id' and
> > 'gpios' property.
> >
> > For example:
> > usb_cable: extcon-gpio-0 {
> > compatible = "extcon-gpio";
> > extcon-id = <EXTCON_USB>;
> > gpios = <&gpio6 1 GPIO_ACTIVE_HIGH>;
> > }
> > ta_cable: extcon-gpio-1 {
> > compatible = "extcon-gpio";
> > extcon-id = <EXTCON_CHG_USB_DCP>;
> > gpios = <&gpio3 2 GPIO_ACTIVE_LOW>;
> > debounce-ms = <50>; /* 50 millisecond */
> > wakeup-source;
> > }
> > &dwc3_usb {
> > extcon = <&usb_cable>;
> > };
> > &charger {
> > extcon = <&ta_cable>;
> > };
> >
> > Signed-off-by: Venkat Reddy Talla <vreddytalla@xxxxxxxxxx>
> > Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> > Signed-off-by: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
> >
> > ---
> > changes from v3:
> > - add description for wakeup-source in documentation
> > - change dts property extcon-gpio name to gpios
> > - use of_get_named_gpio_flags to get gpio number and flags Changes
> > from v2:
> > - Add the more description for 'extcon-id' property in documentation
> > Changes from v1:
> > - Create the include/dt-bindings/extcon/extcon.h including the
> > identification of external connector. These definitions are used in dts file.
> > - Fix error if CONFIG_OF is disabled.
> > - Add signed-off tag by Myungjoo Ham
> > ---
> > ---
> > .../devicetree/bindings/extcon/extcon-gpio.txt | 48 +++++++++
> > drivers/extcon/extcon-gpio.c | 109 +++++++++++++++++----
> > include/dt-bindings/extcon/extcon.h | 47 +++++++++
> > include/linux/extcon/extcon-gpio.h | 8 +-
> > 4 files changed, 189 insertions(+), 23 deletions(-) create mode
> > 100644 Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> > create mode 100644 include/dt-bindings/extcon/extcon.h
> >
> > diff --git a/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> > b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> > new file mode 100644
> > index 0000000..81f7932
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> > @@ -0,0 +1,48 @@
> > +GPIO Extcon device
> > +
> > +This is a virtual device used to generate the specific cable states
> > +from the GPIO pin.
> > +
> > +Required properties:
> > +- compatible: Must be "extcon-gpio".
> > +- extcon-id: The extcon support the various type of external
> > +connector to check
> > + whether connector is attached or detached. The each external
> > +connector has
> > + the unique number to identify it. So this property includes the
> > +unique number
> > + which indicates the specific external connector. When external
> > +connector is
> > + attached or detached, GPIO pin detect the changed state. See
> > +include/
> > + dt-bindings/extcon/extcon.h which defines the unique number for
> > +supported
> > + external connector from extcon framework.
> > +- gpios: GPIO pin to detect the external connector. See gpio binding.
> > +
> > +Optional properties:
> > +- debounce-ms: the debounce dealy for GPIO pin in millisecond.
> > +- wakeup-source: Boolean, extcon can wake-up the system from
> suspend.
> > + if gpio provided in extcon-gpio DT node is registered as interrupt,
> > + then extcon can wake-up the system from suspend if wakeup-source
> > +property
> > + is available in DT node, if gpio registered as interrupt but
> > +wakeup-source
> > + is not available in DT node, then system wake-up due to extcon
> > +events
> > + not supported.
> > +
> > +Example: Examples of extcon-gpio node as listed below:
> > +
> > + usb_cable: extcon-gpio-0 {
> > + compatible = "extcon-gpio";
> > + extcon-id = <EXTCON_USB>;
> > + extcon-gpio = <&gpio6 1 GPIO_ACTIVE_HIGH>;
> > + }
> > +
> > + ta_cable: extcon-gpio-1 {
> > + compatible = "extcon-gpio";
> > + extcon-id = <EXTCON_CHG_USB_DCP>;
> > + extcon-gpio = <&gpio3 2 GPIO_ACTIVE_LOW>;
> > + debounce-ms = <50>; /* 50 millisecond */
> > + wakeup-source;
> > + }
> > +
> > + &dwc3_usb {
> > + extcon = <&usb_cable>;
> > + };
> > +
> > + &charger {
> > + extcon = <&ta_cable>;
> > + };
> > diff --git a/drivers/extcon/extcon-gpio.c
> > b/drivers/extcon/extcon-gpio.c index d023789..592f395 100644
> > --- a/drivers/extcon/extcon-gpio.c
> > +++ b/drivers/extcon/extcon-gpio.c
> > @@ -1,11 +1,9 @@
> > /*
> > * extcon_gpio.c - Single-state GPIO extcon driver based on extcon class
> > *
> > - * Copyright (C) 2008 Google, Inc.
> > - * Author: Mike Lockwood <lockwood@xxxxxxxxxxx>
> > - *
> > - * Modified by MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx> to
> support
> > extcon
> > - * (originally switch class is supported)
> > + * Copyright (C) 2016 Chanwoo Choi <cw00.choi@xxxxxxxxxxx>,
> Samsung
> > + Electronics
> > + * Copyright (C) 2012 MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>,
> > + Samsung Electronics
> > + * Copyright (C) 2008 Mike Lockwood <lockwood@xxxxxxxxxxx>, Google,
> Inc.
> > *
> > * This software is licensed under the terms of the GNU General Public
> > * License version 2, as published by the Free Software Foundation,
> > and @@ -25,13 +23,17 @@ #include <linux/interrupt.h> #include
> > <linux/kernel.h> #include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_gpio.h>
> > #include <linux/platform_device.h>
> > +#include <linux/property.h>
> > #include <linux/slab.h>
> > #include <linux/workqueue.h>
> >
> > struct gpio_extcon_data {
> > struct extcon_dev *edev;
> > int irq;
> > + bool irq_wakeup;
> > struct delayed_work work;
> > unsigned long debounce_jiffies;
> >
> > @@ -49,7 +51,7 @@ static void gpio_extcon_work(struct work_struct
> *work)
> > state = gpiod_get_value_cansleep(data->id_gpiod);
> > if (data->pdata->gpio_active_low)
> > state = !state;
> > - extcon_set_state(data->edev, state);
> > + extcon_set_cable_state_(data->edev, data->pdata->extcon_id,
> > + state);
> > }
> >
> > static irqreturn_t gpio_irq_handler(int irq, void *dev_id) @@ -61,6
> > +63,42 @@ static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
> > return IRQ_HANDLED;
> > }
> >
> > +static int gpio_extcon_parse_of(struct platform_device *pdev,
> > + struct gpio_extcon_data *data) {
> > + struct gpio_extcon_pdata *pdata;
> > + struct device_node *np = pdev->dev.of_node;
> > + enum of_gpio_flags flags;
> > + int ret;
> > +
> > + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> > + if (!pdata)
> > + return -ENOMEM;
> > +
> > + ret = device_property_read_u32(&pdev->dev, "extcon-id",
> > + &pdata->extcon_id);
> > + if (ret < 0)
> > + return -EINVAL;
> > +
> > + pdata->gpio = of_get_named_gpio_flags(np, "gpios", 0, &flags);
> > + if (pdata->gpio < 0)
> > + return -EINVAL;
> > +
> > + if (flags & OF_GPIO_ACTIVE_LOW)
> > + pdata->gpio_active_low = true;
> > +
> > + data->irq_wakeup = device_property_read_bool(&pdev->dev,
> > + "wakeup-source");
> > +
> > + device_property_read_u32(&pdev->dev, "debounce-ms",
> > + &pdata->debounce);
> > +
> > + pdata->irq_flags = (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING
> > + | IRQF_ONESHOT);
> > +
> > + data->pdata = pdata;
> > + return 0;
> > +}
> > +
> > static int gpio_extcon_init(struct device *dev, struct
> > gpio_extcon_data *data) {
> > struct gpio_extcon_pdata *pdata = data->pdata; @@ -96,16
> > +134,20 @@ static int gpio_extcon_probe(struct platform_device *pdev)
> > struct gpio_extcon_data *data;
> > int ret;
> >
> > - if (!pdata)
> > - return -EBUSY;
> > - if (!pdata->irq_flags || pdata->extcon_id > EXTCON_NONE)
> > - return -EINVAL;
> > -
> > - data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_extcon_data),
> > - GFP_KERNEL);
> > + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
> > if (!data)
> > return -ENOMEM;
> > - data->pdata = pdata;
> > +
> > + if (!pdata) {
> > + ret = gpio_extcon_parse_of(pdev, data);
> > + if (ret < 0)
> > + return ret;
> > + } else {
> > + data->pdata = pdata;
> > + }
> > +
> > + if (!data->pdata->irq_flags || data->pdata->extcon_id ==
> EXTCON_NONE)
> > + return -EINVAL;
> >
> > /* Initialize the gpio */
> > ret = gpio_extcon_init(&pdev->dev, data); @@ -113,7 +155,8 @@
> > static int gpio_extcon_probe(struct platform_device *pdev)
> > return ret;
> >
> > /* Allocate the memory of extcon devie and register extcon device */
> > - data->edev = devm_extcon_dev_allocate(&pdev->dev, &pdata-
> >extcon_id);
> > + data->edev = devm_extcon_dev_allocate(&pdev->dev,
> > +
> > + &data->pdata->extcon_id);
> > if (IS_ERR(data->edev)) {
> > dev_err(&pdev->dev, "failed to allocate extcon device\n");
> > return -ENOMEM;
> > @@ -130,7 +173,8 @@ static int gpio_extcon_probe(struct
> platform_device *pdev)
> > * is attached or detached.
> > */
> > ret = devm_request_any_context_irq(&pdev->dev, data->irq,
> > - gpio_irq_handler, pdata->irq_flags,
> > + gpio_irq_handler,
> > + data->pdata->irq_flags,
> > pdev->name, data);
> > if (ret < 0)
> > return ret;
> > @@ -139,6 +183,8 @@ static int gpio_extcon_probe(struct
> platform_device *pdev)
> > /* Perform initial detection */
> > gpio_extcon_work(&data->work.work);
> >
> > + if (data->irq_wakeup)
> > + device_init_wakeup(&pdev->dev, data->irq_wakeup);
> > return 0;
> > }
> >
> > @@ -152,11 +198,23 @@ static int gpio_extcon_remove(struct
> > platform_device *pdev) }
> >
> > #ifdef CONFIG_PM_SLEEP
> > +static int gpio_extcon_suspend(struct device *dev) {
> > + struct gpio_extcon_data *data = dev_get_drvdata(dev);
> > +
> > + if (data->irq_wakeup)
> > + enable_irq_wake(data->irq);
> > +
> > + return 0;
> > +}
> > +
> > static int gpio_extcon_resume(struct device *dev) {
> > - struct gpio_extcon_data *data;
> > + struct gpio_extcon_data *data = dev_get_drvdata(dev);
> > +
> > + if (data->irq_wakeup)
> > + disable_irq_wake(data->irq);
> >
> > - data = dev_get_drvdata(dev);
> > if (data->pdata->check_on_resume)
> > queue_delayed_work(system_power_efficient_wq,
> > &data->work, data->debounce_jiffies); @@
> > -165,7 +223,18 @@ static int gpio_extcon_resume(struct device *dev) }
> > #endif
> >
> > -static SIMPLE_DEV_PM_OPS(gpio_extcon_pm_ops, NULL,
> > gpio_extcon_resume);
> > +#if defined(CONFIG_OF)
> > +static const struct of_device_id gpio_extcon_of_match[] = {
> > + { .compatible = "extcon-gpio", },
> > + { /* sentinel */ },
> > +};
> > +MODULE_DEVICE_TABLE(of, gpio_extcon_of_match); #else
> > +#define gpio_extcon_of_match NULL
> > +#endif
> > +
> > +static SIMPLE_DEV_PM_OPS(gpio_extcon_pm_ops,
> > + gpio_extcon_suspend, gpio_extcon_resume);
> >
> > static struct platform_driver gpio_extcon_driver = {
> > .probe = gpio_extcon_probe,
> > @@ -173,11 +242,13 @@ static struct platform_driver gpio_extcon_driver =
> {
> > .driver = {
> > .name = "extcon-gpio",
> > .pm = &gpio_extcon_pm_ops,
> > + .of_match_table = gpio_extcon_of_match,
> > },
> > };
> >
> > module_platform_driver(gpio_extcon_driver);
> >
> > +MODULE_AUTHOR("Chanwoo Choi <cw00.choi@xxxxxxxxxxx>");
> > MODULE_AUTHOR("Mike Lockwood <lockwood@xxxxxxxxxxx>");
> > MODULE_DESCRIPTION("GPIO extcon driver"); MODULE_LICENSE("GPL");
> diff
> > --git a/include/dt-bindings/extcon/extcon.h
> > b/include/dt-bindings/extcon/extcon.h
> > new file mode 100644
> > index 0000000..dbba588
> > --- /dev/null
> > +++ b/include/dt-bindings/extcon/extcon.h
> > @@ -0,0 +1,47 @@
> > +/*
> > + * This header provides constants for most extcon bindings.
> > + *
> > + * Most extcon bindings include the unique identification format.
> > + * In most cases, the unique id format uses the standard values/macro
> > + * defined in this header.
> > + */
> > +
> > +#ifndef _DT_BINDINGS_EXTCON_EXTCON_H
> > +#define _DT_BINDINGS_EXTCON_EXTCON_H
> > +
> > +/* USB external connector */
> > +#define EXTCON_USB 1
> > +#define EXTCON_USB_HOST 2
> > +
> > +/* Charging external connector */
> > +#define EXTCON_CHG_USB_SDP 5 /* Standard Downstream Port */
> > +#define EXTCON_CHG_USB_DCP 6 /* Dedicated Charging Port */
> > +#define EXTCON_CHG_USB_CDP 7 /* Charging Downstream Port */
> > +#define EXTCON_CHG_USB_ACA 8 /* Accessory Charger Adapter */
> > +#define EXTCON_CHG_USB_FAST 9
> > +#define EXTCON_CHG_USB_SLOW 10
> > +
> > +/* Jack external connector */
> > +#define EXTCON_JACK_MICROPHONE 20
> > +#define EXTCON_JACK_HEADPHONE 21
> > +#define EXTCON_JACK_LINE_IN 22
> > +#define EXTCON_JACK_LINE_OUT 23
> > +#define EXTCON_JACK_VIDEO_IN 24
> > +#define EXTCON_JACK_VIDEO_OUT 25
> > +#define EXTCON_JACK_SPDIF_IN 26 /* Sony Philips Digital InterFace
> */
> > +#define EXTCON_JACK_SPDIF_OUT 27
> > +
> > +/* Display external connector */
> > +#define EXTCON_DISP_HDMI 40 /* High-Definition Multimedia
> Interface */
> > +#define EXTCON_DISP_MHL 41 /* Mobile High-Definition Link
> */
> > +#define EXTCON_DISP_DVI 42 /* Digital Visual Interface */
> > +#define EXTCON_DISP_VGA 43 /* Video Graphics Array */
> > +
> > +/* Miscellaneous external connector */
> > +#define EXTCON_DOCK 60
> > +#define EXTCON_JIG 61
> > +#define EXTCON_MECHANICAL 62
> > +
> > +#define EXTCON_NUM 63
> > +
> > +#endif /* _DT_BINDINGS_EXTCON_EXTCON_H */
> > diff --git a/include/linux/extcon/extcon-gpio.h
> > b/include/linux/extcon/extcon-gpio.h
> > index 7cacafb..f7e7673 100644
> > --- a/include/linux/extcon/extcon-gpio.h
> > +++ b/include/linux/extcon/extcon-gpio.h
> > @@ -1,8 +1,8 @@
> > /*
> > * Single-state GPIO extcon driver based on extcon class
> > *
> > - * Copyright (C) 2012 Samsung Electronics
> > - * Author: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
> > + * Copyright (C) 2016 Chanwoo Choi <cw00.choi@xxxxxxxxxxx>,
> Samsung
> > + Electronics
> > + * Copyright (C) 2012 MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>,
> > + Samsung Electronics
> > *
> > * based on switch class driver
> > * Copyright (C) 2008 Google, Inc.
> > @@ -35,10 +35,10 @@
> > * while resuming from sleep.
> > */
> > struct gpio_extcon_pdata {
> > - unsigned int extcon_id;
> > + u32 extcon_id;
> > unsigned gpio;
> > bool gpio_active_low;
> > - unsigned long debounce;
> > + u32 debounce;
> > unsigned long irq_flags;
> >
> > bool check_on_resume;
> > --
> > 2.1.4
> >