diff mbox

[v5] extcon: add Maxim MAX3355 driver

Message ID 5948633.my3nAG6hRz@wasted.cogentembedded.com
State Not Applicable, archived
Headers show

Commit Message

Sergei Shtylyov Dec. 18, 2015, 11:17 p.m. UTC
Maxim Integrated MAX3355E chip integrates a charge pump and comparators to
enable a system with an integrated USB OTG dual-role transceiver to
function as an USB OTG dual-role device. In addition to sensing/controlling
Vbus, the chip also passes thru the ID signal from the USB OTG connector.
On some Renesas boards, this signal is just fed into the SoC thru a GPIO
pin -- there's no real OTG controller, only host and gadget USB controllers
sharing the same USB bus; however, we'd like to allow host or gadget
drivers to be loaded depending on the cable type, hence the need for the
MAX3355 extcon driver. The Vbus status signals are also wired to GPIOs
(however, we aren't currently interested in them), the OFFVBUS# signal is
controlled by the host controllers, there's also the SHDN# signal wired to
a GPIO, it should be driven high for the normal operation.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>

---
Changes in version 5:
- removed unused variable in the probe() method;
- removed reference to the Koelsch board from the binding document;
- added Chanwoo Choi's ACK.

Changes in version 4:
- stopped calling kstrdup() for the device name;
- removed unneeded 'owner' field initializer;
- moved devm_extcon_allocate() call further down in the probe() method;
- extended the driver copyright;
- indented the continuation lines in the binding document.

Changes in version 3:
- reformatted the change log.

Changes in version 2:
- added the USB gadget cable support;
- added the remove() driver method which drives SHDN# GPIO low to save power;
- dropped vendor prefix from the ID GPIO property name;
- changed the GPIO property name suffix to "-gpios";
- switched to usign extcon_set_cable_state_() API;
- switched to using the gpiod/sleeping 'gpiolib' APIs;
- addded error messages to max3355_probe();
- added IRQF_NO_SUSPEND flasg to the devm_request_threaded_irq() call;
- renamed 'ret' variable to 'err' in max3355_probe();
- expanded the Kconfig entry help text;
- added vendor name to the patch summary, the bindings document, the Kconfig
  entry, the driver heading comment, the module description, and the change log;
- fixed up and reformatted the change log.

 Documentation/devicetree/bindings/extcon/extcon-max3355.txt |   21 +
 drivers/extcon/Kconfig                                      |    8 
 drivers/extcon/Makefile                                     |    1 
 drivers/extcon/extcon-max3355.c                             |  150 ++++++++++++
 4 files changed, 180 insertions(+)


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Comments

Sergei Shtylyov Dec. 20, 2015, 5:15 p.m. UTC | #1
Hello.

On 12/20/2015 05:31 PM, Chanwoo Choi wrote:

> This patch depend on GPIOLIB configuration as following:
> I modified it with following diff and applied it.
>
> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
> index ba4db7d..3d89e60 100644
> --- a/drivers/extcon/Kconfig
> +++ b/drivers/extcon/Kconfig
> @@ -54,6 +54,7 @@ config EXTCON_MAX14577
>
>   config EXTCON_MAX3355
>          tristate "Maxim MAX3355 USB OTG EXTCON Support"
> +       depends on GPIOLIB || COMPILE_TEST

    If it won't compile w/o gpiolib, what's the use of COMIPLE_TEST?
    And no, it shouldn't depend on gpiolib. It has empty stubs for the case of 
CONFIG_GPIOLIB=n. Obviously something is wrong with the GPIO headers, I'll 
look into it.

[...]

> Thanks,
> Chanwoo Choi

MBR, Sergei

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Chanwoo Choi Dec. 21, 2015, 2:38 a.m. UTC | #2
Hi,

On 2015년 12월 21일 02:15, Sergei Shtylyov wrote:
> Hello.
> 
> On 12/20/2015 05:31 PM, Chanwoo Choi wrote:
> 
>> This patch depend on GPIOLIB configuration as following:
>> I modified it with following diff and applied it.
>>
>> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
>> index ba4db7d..3d89e60 100644
>> --- a/drivers/extcon/Kconfig
>> +++ b/drivers/extcon/Kconfig
>> @@ -54,6 +54,7 @@ config EXTCON_MAX14577
>>
>>   config EXTCON_MAX3355
>>          tristate "Maxim MAX3355 USB OTG EXTCON Support"
>> +       depends on GPIOLIB || COMPILE_TEST
> 
>    If it won't compile w/o gpiolib, what's the use of COMIPLE_TEST?
>    And no, it shouldn't depend on gpiolib. It has empty stubs for the case of CONFIG_GPIOLIB=n. Obviously something is wrong with the GPIO headers, I'll look into it.

Yes. When GPIOLIB is disabled, the build issue don't happen.
because include/linux/gpio/consumer.h implement the dummy function
for all gpio functions if CONFIG_GPIOLIB is disabled.

For correct operation of max3355, you should add the dependency 
to the extcon-max3355.c driver. This driver use the GPIO library
certainly.

COMPILE_TEST is used for just build test. You can see the detailed data[1].
[1] https://lkml.org/lkml/2013/5/22/155

Thanks,
Chanwoo Choi
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Sergei Shtylyov Dec. 21, 2015, 11:01 a.m. UTC | #3
Hello.

On 12/21/2015 5:38 AM, Chanwoo Choi wrote:

>>> This patch depend on GPIOLIB configuration as following:
>>> I modified it with following diff and applied it.
>>>
>>> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
>>> index ba4db7d..3d89e60 100644
>>> --- a/drivers/extcon/Kconfig
>>> +++ b/drivers/extcon/Kconfig
>>> @@ -54,6 +54,7 @@ config EXTCON_MAX14577
>>>
>>>    config EXTCON_MAX3355
>>>           tristate "Maxim MAX3355 USB OTG EXTCON Support"
>>> +       depends on GPIOLIB || COMPILE_TEST
>>
>>     If it won't compile w/o gpiolib, what's the use of COMIPLE_TEST?
>>     And no, it shouldn't depend on gpiolib. It has empty stubs for the case of CONFIG_GPIOLIB=n. Obviously something is wrong with the GPIO headers, I'll look into it.
>
> Yes. When GPIOLIB is disabled, the build issue don't happen.

    What? It surely does happen!

> because include/linux/gpio/consumer.h implement the dummy function
> for all gpio functions if CONFIG_GPIOLIB is disabled.

    Linus W. advised to #include this header explicitly -- I'll try and post.

> For correct operation of max3355, you should add the dependency
> to the extcon-max3355.c driver. This driver use the GPIO library
> certainly.

    I disagree. The driver will just cease to load in this case. I don't see 
why we need such dependency. Only compilation time dependencies should be
specified, I think.

> COMPILE_TEST is used for just build test. You can see the detailed data[1].
> [1] https://lkml.org/lkml/2013/5/22/155

    I know. Re-read my question please.

> Thanks,
> Chanwoo Choi

MBR, Sergei

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Sergei Shtylyov Dec. 21, 2015, 7:38 p.m. UTC | #4
Hello.

On 12/21/2015 02:01 PM, Sergei Shtylyov wrote:

>>>> This patch depend on GPIOLIB configuration as following:
>>>> I modified it with following diff and applied it.
>>>>
>>>> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
>>>> index ba4db7d..3d89e60 100644
>>>> --- a/drivers/extcon/Kconfig
>>>> +++ b/drivers/extcon/Kconfig
>>>> @@ -54,6 +54,7 @@ config EXTCON_MAX14577
>>>>
>>>>    config EXTCON_MAX3355
>>>>           tristate "Maxim MAX3355 USB OTG EXTCON Support"
>>>> +       depends on GPIOLIB || COMPILE_TEST
>>>
>>>     If it won't compile w/o gpiolib, what's the use of COMIPLE_TEST?
>>>     And no, it shouldn't depend on gpiolib. It has empty stubs for the case
>>> of CONFIG_GPIOLIB=n. Obviously something is wrong with the GPIO headers,
>>> I'll look into it.
>>
>> Yes. When GPIOLIB is disabled, the build issue don't happen.
>
>     What? It surely does happen!
>
>> because include/linux/gpio/consumer.h implement the dummy function
>> for all gpio functions if CONFIG_GPIOLIB is disabled.
>
>     Linus W. advised to #include this header explicitly -- I'll try and post.

    I see you already #include'd it, thanks. But in that case, <linux/gpio.h> 
doesn't seem necessary.

>> Thanks,
>> Chanwoo Choi

MBR, Sergei

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Chanwoo Choi Dec. 22, 2015, 1:13 a.m. UTC | #5
On 2015년 12월 21일 20:01, Sergei Shtylyov wrote:
> Hello.
> 
> On 12/21/2015 5:38 AM, Chanwoo Choi wrote:
> 
>>>> This patch depend on GPIOLIB configuration as following:
>>>> I modified it with following diff and applied it.
>>>>
>>>> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
>>>> index ba4db7d..3d89e60 100644
>>>> --- a/drivers/extcon/Kconfig
>>>> +++ b/drivers/extcon/Kconfig
>>>> @@ -54,6 +54,7 @@ config EXTCON_MAX14577
>>>>
>>>>    config EXTCON_MAX3355
>>>>           tristate "Maxim MAX3355 USB OTG EXTCON Support"
>>>> +       depends on GPIOLIB || COMPILE_TEST
>>>
>>>     If it won't compile w/o gpiolib, what's the use of COMIPLE_TEST?
>>>     And no, it shouldn't depend on gpiolib. It has empty stubs for the case of CONFIG_GPIOLIB=n. Obviously something is wrong with the GPIO headers, I'll look into it.
>>
>> Yes. When GPIOLIB is disabled, the build issue don't happen.
> 
>    What? It surely does happen!

hmm....
Sure. you need to check the include/linux/gpio/consumer.h.

Because of build error happen, you miss to include the "linux/gpio/consumer.h"
header file in extcon-max3355.c. Please test it for enough time.

> 
>> because include/linux/gpio/consumer.h implement the dummy function
>> for all gpio functions if CONFIG_GPIOLIB is disabled.
> 
>    Linus W. advised to #include this header explicitly -- I'll try and post.

Don't necessary. I already updated it including the "include/linux/gpio/consumer.h".

> 
>> For correct operation of max3355, you should add the dependency
>> to the extcon-max3355.c driver. This driver use the GPIO library
>> certainly.
> 
>    I disagree. The driver will just cease to load in this case. I don't see why we need such dependency. Only compilation time dependencies should be
> specified, I think.

This driver have to depend on GPIOLIB.
Why are you disagreeing the COMPILE_TEST dependency? It is just compile test
without anything. 
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Sergei Shtylyov Dec. 22, 2015, 11:15 a.m. UTC | #6
Hello.

On 12/22/2015 4:13 AM, Chanwoo Choi wrote:

>>>>> This patch depend on GPIOLIB configuration as following:
>>>>> I modified it with following diff and applied it.
>>>>>
>>>>> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
>>>>> index ba4db7d..3d89e60 100644
>>>>> --- a/drivers/extcon/Kconfig
>>>>> +++ b/drivers/extcon/Kconfig
>>>>> @@ -54,6 +54,7 @@ config EXTCON_MAX14577
>>>>>
>>>>>     config EXTCON_MAX3355
>>>>>            tristate "Maxim MAX3355 USB OTG EXTCON Support"
>>>>> +       depends on GPIOLIB || COMPILE_TEST
>>>>
>>>>      If it won't compile w/o gpiolib, what's the use of COMIPLE_TEST?
>>>>      And no, it shouldn't depend on gpiolib. It has empty stubs for the case of CONFIG_GPIOLIB=n. Obviously something is wrong with the GPIO headers, I'll look into it.
>>>
>>> Yes. When GPIOLIB is disabled, the build issue don't happen.
>>
>>     What? It surely does happen!
>
> hmm....
> Sure. you need to check the include/linux/gpio/consumer.h.
>
> Because of build error happen, you miss to include the "linux/gpio/consumer.h"
> header file in extcon-max3355.c. Please test it for enough time.

    Yes, with this file #include'd, it build fine now.

>>> because include/linux/gpio/consumer.h implement the dummy function
>>> for all gpio functions if CONFIG_GPIOLIB is disabled.
>>
>>     Linus W. advised to #include this header explicitly -- I'll try and post.
>
> Don't necessary. I already updated it including the "include/linux/gpio/consumer.h".

    I saw that, yes.

>>> For correct operation of max3355, you should add the dependency
>>> to the extcon-max3355.c driver. This driver use the GPIO library
>>> certainly.
>>
>>     I disagree. The driver will just cease to load in this case. I don't see why we need such dependency. Only compilation time dependencies should be
>> specified, I think.
>
> This driver have to depend on GPIOLIB.
> Why are you disagreeing the COMPILE_TEST dependency? It is just compile test
> without anything.

    I agree now. I still disagree about the gpiolib dependency though.

MBR, Sergei

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Chanwoo Choi Dec. 23, 2015, 2:17 a.m. UTC | #7
On 2015년 12월 22일 20:15, Sergei Shtylyov wrote:
> Hello.
> 
> On 12/22/2015 4:13 AM, Chanwoo Choi wrote:
> 
>>>>>> This patch depend on GPIOLIB configuration as following:
>>>>>> I modified it with following diff and applied it.
>>>>>>
>>>>>> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
>>>>>> index ba4db7d..3d89e60 100644
>>>>>> --- a/drivers/extcon/Kconfig
>>>>>> +++ b/drivers/extcon/Kconfig
>>>>>> @@ -54,6 +54,7 @@ config EXTCON_MAX14577
>>>>>>
>>>>>>     config EXTCON_MAX3355
>>>>>>            tristate "Maxim MAX3355 USB OTG EXTCON Support"
>>>>>> +       depends on GPIOLIB || COMPILE_TEST
>>>>>
>>>>>      If it won't compile w/o gpiolib, what's the use of COMIPLE_TEST?
>>>>>      And no, it shouldn't depend on gpiolib. It has empty stubs for the case of CONFIG_GPIOLIB=n. Obviously something is wrong with the GPIO headers, I'll look into it.
>>>>
>>>> Yes. When GPIOLIB is disabled, the build issue don't happen.
>>>
>>>     What? It surely does happen!
>>
>> hmm....
>> Sure. you need to check the include/linux/gpio/consumer.h.
>>
>> Because of build error happen, you miss to include the "linux/gpio/consumer.h"
>> header file in extcon-max3355.c. Please test it for enough time.
> 
>    Yes, with this file #include'd, it build fine now.
> 
>>>> because include/linux/gpio/consumer.h implement the dummy function
>>>> for all gpio functions if CONFIG_GPIOLIB is disabled.
>>>
>>>     Linus W. advised to #include this header explicitly -- I'll try and post.
>>
>> Don't necessary. I already updated it including the "include/linux/gpio/consumer.h".
> 
>    I saw that, yes.
> 
>>>> For correct operation of max3355, you should add the dependency
>>>> to the extcon-max3355.c driver. This driver use the GPIO library
>>>> certainly.
>>>
>>>     I disagree. The driver will just cease to load in this case. I don't see why we need such dependency. Only compilation time dependencies should be
>>> specified, I think.
>>
>> This driver have to depend on GPIOLIB.
>> Why are you disagreeing the COMPILE_TEST dependency? It is just compile test
>> without anything.
> 
>    I agree now. I still disagree about the gpiolib dependency though.

If gpiolib is disabled, extcon-max3355.c might not operate it correctly.
Just this driver could be built without operation because gpiolib function
will not do the any behavior.

I think that it is not too much problem. I should send the pull request within this week.
If you want to need more discussion of extcon-max3355.c,
I will not include it on pull request for v4.5 because there is issue.



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Sergei Shtylyov Dec. 23, 2015, 7:56 p.m. UTC | #8
Hello.

On 12/23/2015 05:17 AM, Chanwoo Choi wrote:

>>>>>>> This patch depend on GPIOLIB configuration as following:
>>>>>>> I modified it with following diff and applied it.
>>>>>>>
>>>>>>> diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
>>>>>>> index ba4db7d..3d89e60 100644
>>>>>>> --- a/drivers/extcon/Kconfig
>>>>>>> +++ b/drivers/extcon/Kconfig
>>>>>>> @@ -54,6 +54,7 @@ config EXTCON_MAX14577
>>>>>>>
>>>>>>>      config EXTCON_MAX3355
>>>>>>>             tristate "Maxim MAX3355 USB OTG EXTCON Support"
>>>>>>> +       depends on GPIOLIB || COMPILE_TEST
>>>>>>
>>>>>>       If it won't compile w/o gpiolib, what's the use of COMIPLE_TEST?
>>>>>>       And no, it shouldn't depend on gpiolib. It has empty stubs for the case of CONFIG_GPIOLIB=n. Obviously something is wrong with the GPIO headers, I'll look into it.
>>>>>
>>>>> Yes. When GPIOLIB is disabled, the build issue don't happen.
>>>>
>>>>      What? It surely does happen!
>>>
>>> hmm....
>>> Sure. you need to check the include/linux/gpio/consumer.h.
>>>
>>> Because of build error happen, you miss to include the "linux/gpio/consumer.h"
>>> header file in extcon-max3355.c. Please test it for enough time.
>>
>>     Yes, with this file #include'd, it build fine now.
>>
>>>>> because include/linux/gpio/consumer.h implement the dummy function
>>>>> for all gpio functions if CONFIG_GPIOLIB is disabled.
>>>>
>>>>      Linus W. advised to #include this header explicitly -- I'll try and post.
>>>
>>> Don't necessary. I already updated it including the "include/linux/gpio/consumer.h".
>>
>>     I saw that, yes.
>>
>>>>> For correct operation of max3355, you should add the dependency
>>>>> to the extcon-max3355.c driver. This driver use the GPIO library
>>>>> certainly.
>>>>
>>>>      I disagree. The driver will just cease to load in this case. I don't see why we need such dependency. Only compilation time dependencies should be
>>>> specified, I think.
>>>
>>> This driver have to depend on GPIOLIB.
>>> Why are you disagreeing the COMPILE_TEST dependency? It is just compile test
>>> without anything.
>>
>>     I agree now. I still disagree about the gpiolib dependency though.
>
> If gpiolib is disabled, extcon-max3355.c might not operate it correctly.

    It'll just fail the probe, that's all.

> Just this driver could be built without operation because gpiolib function
> will not do the any behavior.

    devm_gpiod_get() will just fail with -ENOSYS.

> I think that it is not too much problem. I should send the pull request within this week.
> If you want to need more discussion of extcon-max3355.c,
> I will not include it on pull request for v4.5 because there is issue.

    No, please include it into the pull request.

MBR, Sergei

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diff mbox

Patch

Index: extcon/Documentation/devicetree/bindings/extcon/extcon-max3355.txt
===================================================================
--- /dev/null
+++ extcon/Documentation/devicetree/bindings/extcon/extcon-max3355.txt
@@ -0,0 +1,21 @@ 
+Maxim Integrated MAX3355 USB OTG chip
+-------------------------------------
+
+MAX3355 integrates a charge pump and comparators to enable a system with an
+integrated USB OTG dual-role transceiver to function as a USB OTG dual-role
+device.
+
+Required properties:
+- compatible: should be "maxim,max3355";
+- maxim,shdn-gpios: should contain a phandle and GPIO specifier for the GPIO pin
+		    connected to the MAX3355's SHDN# pin;
+- id-gpios: should contain a phandle and GPIO specifier for the GPIO pin
+	    connected to the MAX3355's ID_OUT pin.
+
+Example:
+
+	usb-otg {
+		compatible = "maxim,max3355";
+		maxim,shdn-gpios = <&gpio2 4 GPIO_ACTIVE_LOW>;
+		id-gpios = <&gpio5 31 GPIO_ACTIVE_HIGH>;
+	};
Index: extcon/drivers/extcon/Kconfig
===================================================================
--- extcon.orig/drivers/extcon/Kconfig
+++ extcon/drivers/extcon/Kconfig
@@ -52,6 +52,14 @@  config EXTCON_MAX14577
 	  Maxim MAX14577/77836. The MAX14577/77836 MUIC is a USB port accessory
 	  detector and switch.
 
+config EXTCON_MAX3355
+	tristate "Maxim MAX3355 USB OTG EXTCON Support"
+	help
+	  If you say yes here you get support for the USB OTG role detection by
+	  MAX3355. The MAX3355 chip integrates a charge pump and comparators to
+	  enable a system with an integrated USB OTG dual-role transceiver to
+	  function as an USB OTG dual-role device.
+
 config EXTCON_MAX77693
 	tristate "Maxim MAX77693 EXTCON Support"
 	depends on MFD_MAX77693 && INPUT
Index: extcon/drivers/extcon/Makefile
===================================================================
--- extcon.orig/drivers/extcon/Makefile
+++ extcon/drivers/extcon/Makefile
@@ -8,6 +8,7 @@  obj-$(CONFIG_EXTCON_ARIZONA)	+= extcon-a
 obj-$(CONFIG_EXTCON_AXP288)	+= extcon-axp288.o
 obj-$(CONFIG_EXTCON_GPIO)	+= extcon-gpio.o
 obj-$(CONFIG_EXTCON_MAX14577)	+= extcon-max14577.o
+obj-$(CONFIG_EXTCON_MAX3355)	+= extcon-max3355.o
 obj-$(CONFIG_EXTCON_MAX77693)	+= extcon-max77693.o
 obj-$(CONFIG_EXTCON_MAX77843)	+= extcon-max77843.o
 obj-$(CONFIG_EXTCON_MAX8997)	+= extcon-max8997.o
Index: extcon/drivers/extcon/extcon-max3355.c
===================================================================
--- /dev/null
+++ extcon/drivers/extcon/extcon-max3355.c
@@ -0,0 +1,150 @@ 
+/*
+ * Maxim Integrated MAX3355 USB OTG chip extcon driver
+ *
+ * Copyright (C)  2014-2015 Cogent Embedded, Inc.
+ * Author: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ */
+
+#include <linux/extcon.h>
+#include <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+struct max3355_data {
+	struct extcon_dev *edev;
+	struct gpio_desc *id_gpiod;
+	struct gpio_desc *shdn_gpiod;
+};
+
+static const unsigned int max3355_cable[] = {
+	EXTCON_USB,
+	EXTCON_USB_HOST,
+	EXTCON_NONE,
+};
+
+static irqreturn_t max3355_id_irq(int irq, void *dev_id)
+{
+	struct max3355_data *data = dev_id;
+	int id = gpiod_get_value_cansleep(data->id_gpiod);
+
+	if (id) {
+		/*
+		 * ID = 1 means USB HOST cable detached.
+		 * As we don't have event for USB peripheral cable attached,
+		 * we simulate USB peripheral attach here.
+		 */
+		extcon_set_cable_state_(data->edev, EXTCON_USB_HOST, false);
+		extcon_set_cable_state_(data->edev, EXTCON_USB, true);
+	} else {
+		/*
+		 * ID = 0 means USB HOST cable attached.
+		 * As we don't have event for USB peripheral cable detached,
+		 * we simulate USB peripheral detach here.
+		 */
+		extcon_set_cable_state_(data->edev, EXTCON_USB, false);
+		extcon_set_cable_state_(data->edev, EXTCON_USB_HOST, true);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int max3355_probe(struct platform_device *pdev)
+{
+	struct max3355_data *data;
+	struct gpio_desc *gpiod;
+	int irq, err;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(struct max3355_data),
+			    GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	gpiod = devm_gpiod_get(&pdev->dev, "id", GPIOD_IN);
+	if (IS_ERR(gpiod)) {
+		dev_err(&pdev->dev, "failed to get ID_OUT GPIO\n");
+		return PTR_ERR(gpiod);
+	}
+	data->id_gpiod = gpiod;
+
+	gpiod = devm_gpiod_get(&pdev->dev, "maxim,shdn", GPIOD_OUT_HIGH);
+	if (IS_ERR(gpiod)) {
+		dev_err(&pdev->dev, "failed to get SHDN# GPIO\n");
+		return PTR_ERR(gpiod);
+	}
+	data->shdn_gpiod = gpiod;
+
+	data->edev = devm_extcon_dev_allocate(&pdev->dev, max3355_cable);
+	if (IS_ERR(data->edev)) {
+		dev_err(&pdev->dev, "failed to allocate extcon device\n");
+		return PTR_ERR(data->edev);
+	}
+
+	err = devm_extcon_dev_register(&pdev->dev, data->edev);
+	if (err < 0) {
+		dev_err(&pdev->dev, "failed to register extcon device\n");
+		return err;
+	}
+
+	irq = gpiod_to_irq(data->id_gpiod);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to translate ID_OUT GPIO to IRQ\n");
+		return irq;
+	}
+
+	err = devm_request_threaded_irq(&pdev->dev, irq, NULL, max3355_id_irq,
+					IRQF_ONESHOT | IRQF_NO_SUSPEND |
+					IRQF_TRIGGER_RISING |
+					IRQF_TRIGGER_FALLING,
+					pdev->name, data);
+	if (err < 0) {
+		dev_err(&pdev->dev, "failed to request ID_OUT IRQ\n");
+		return err;
+	}
+
+	platform_set_drvdata(pdev, data);
+
+	/* Perform initial detection */
+	max3355_id_irq(irq, data);
+
+	return 0;
+}
+
+static int max3355_remove(struct platform_device *pdev)
+{
+	struct max3355_data *data = platform_get_drvdata(pdev);
+
+	gpiod_set_value_cansleep(data->shdn_gpiod, 0);
+
+	return 0;
+}
+
+static const struct of_device_id max3355_match_table[] = {
+	{ .compatible = "maxim,max3355", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, max3355_match_table);
+
+static struct platform_driver max3355_driver = {
+	.probe		= max3355_probe,
+	.remove		= max3355_remove,
+	.driver		= {
+		.name	= "extcon-max3355",
+		.of_match_table = max3355_match_table,
+	},
+};
+
+module_platform_driver(max3355_driver);
+
+MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>");
+MODULE_DESCRIPTION("Maxim MAX3355 extcon driver");
+MODULE_LICENSE("GPL v2");