diff mbox

[v11,2/8] Input: goodix - reset device at init

Message ID 1447936001-21420-3-git-send-email-irina.tirdea@intel.com (mailing list archive)
State Accepted
Headers show

Commit Message

tip-bot for Irina Tirdea Nov. 19, 2015, 12:26 p.m. UTC
After power on, it is recommended that the driver resets the device.
The reset procedure timing is described in the datasheet and is used
at device init (before writing device configuration) and
for power management. It is a sequence of setting the interrupt
and reset pins high/low at specific timing intervals. This procedure
also includes setting the slave address to the one specified in the
ACPI/device tree.

This is based on Goodix datasheets for GT911 and GT9271 and on Goodix
driver gt9xx.c for Android (publicly available in Android kernel
trees for various devices).

For reset the driver needs to control the interrupt and
reset gpio pins (configured through ACPI/device tree). For devices
that do not have the gpio pins properly declared, the functionality
depending on these pins will not be available, but the device can still
be used with basic functionality.

For both device tree and ACPI, the interrupt gpio pin configuration is
read from the "irq-gpios" property and the reset pin configuration is
read from the "reset-gpios" property. For ACPI 5.1, named properties
can be specified using the _DSD section. This functionality will not be
available for devices that use indexed gpio pins declared in the _CRS
section (we need to provide backward compatibility with devices
that do not support using the interrupt gpio pin as output).

For ACPI, the pins can be specified using ACPI 5.1:
Device (STAC)
{
    Name (_HID, "GDIX1001")
    ...

    Method (_CRS, 0, Serialized)
    {
        Name (RBUF, ResourceTemplate ()
        {
            I2cSerialBus (0x0014, ControllerInitiated, 0x00061A80,
                AddressingMode7Bit, "\\I2C0",
                0x00, ResourceConsumer, ,
                )

            GpioInt (Edge, ActiveHigh, Exclusive, PullNone, 0x0000,
                "\\I2C0", 0x00, ResourceConsumer, ,
                 )
                 {   // Pin list
                     0
                 }

            GpioIo (Exclusive, PullDown, 0x0000, 0x0000,
                IoRestrictionOutputOnly, "\\I2C0", 0x00,
                ResourceConsumer, ,
                )
                {
                     1
                }
        })
        Return (RBUF)
    }

    Name (_DSD,  Package ()
    {
        ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
        Package ()
        {
            Package (2) {"irq-gpios", Package() {^STAC, 0, 0, 0 }},
            Package (2) {"reset-gpios", Package() {^STAC, 1, 0, 0 }},
            ...
        }
    }

Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
---
 .../bindings/input/touchscreen/goodix.txt          |   9 ++
 drivers/input/touchscreen/Kconfig                  |   1 +
 drivers/input/touchscreen/goodix.c                 | 101 +++++++++++++++++++++
 3 files changed, 111 insertions(+)

Comments

Bastien Nocera Nov. 19, 2015, 3:25 p.m. UTC | #1
On Thu, 2015-11-19 at 14:26 +0200, Irina Tirdea wrote:
> After power on, it is recommended that the driver resets the device.
> The reset procedure timing is described in the datasheet and is used
> at device init (before writing device configuration) and
> for power management. It is a sequence of setting the interrupt
> and reset pins high/low at specific timing intervals. This procedure
> also includes setting the slave address to the one specified in the
> ACPI/device tree.

This fails on a 4.3 kernel with an ACPI device (WinBook TW100):
Goodix-TS: probe of i2c-GDIX1001:00 failed with error -16

Can you please document which upstream commit is necessary to make this
behave properly?

I'll test again with a newer kernel.

Cheers
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tip-bot for Irina Tirdea Nov. 19, 2015, 3:36 p.m. UTC | #2
> -----Original Message-----

> From: Bastien Nocera [mailto:hadess@hadess.net]

> Sent: 19 November, 2015 17:25

> To: Tirdea, Irina; Dmitry Torokhov; Aleksei Mamlin; Karsten Merker; linux-input@vger.kernel.org

> Cc: Mark Rutland; Rob Herring; Purdila, Octavian; linux-kernel@vger.kernel.org; devicetree@vger.kernel.org

> Subject: Re: [PATCH v11 2/8] Input: goodix - reset device at init

> 

> On Thu, 2015-11-19 at 14:26 +0200, Irina Tirdea wrote:

> > After power on, it is recommended that the driver resets the device.

> > The reset procedure timing is described in the datasheet and is used

> > at device init (before writing device configuration) and

> > for power management. It is a sequence of setting the interrupt

> > and reset pins high/low at specific timing intervals. This procedure

> > also includes setting the slave address to the one specified in the

> > ACPI/device tree.

> 

> This fails on a 4.3 kernel with an ACPI device (WinBook TW100):

> Goodix-TS: probe of i2c-GDIX1001:00 failed with error -16

> 

> Can you please document which upstream commit is necessary to make this

> behave properly?

> 


You need the patch that fixes the GPIO API [1] so that
devm_gpiod_get_optional works properly (I mentioned that in the cover
letter). This patch just got merged in the gpio tree, so it will take a
while until it will be merged in the main kernel tree or input tree. 

Thanks,
Irina

 [1] https://lkml.org/lkml/2015/11/11/465

> I'll test again with a newer kernel.

> 

> Cheers
Rob Herring (Arm) Nov. 20, 2015, 3:41 p.m. UTC | #3
On Thu, Nov 19, 2015 at 02:26:35PM +0200, Irina Tirdea wrote:
> After power on, it is recommended that the driver resets the device.
> The reset procedure timing is described in the datasheet and is used
> at device init (before writing device configuration) and
> for power management. It is a sequence of setting the interrupt
> and reset pins high/low at specific timing intervals. This procedure
> also includes setting the slave address to the one specified in the
> ACPI/device tree.
> 
> This is based on Goodix datasheets for GT911 and GT9271 and on Goodix
> driver gt9xx.c for Android (publicly available in Android kernel
> trees for various devices).
> 
> For reset the driver needs to control the interrupt and
> reset gpio pins (configured through ACPI/device tree). For devices
> that do not have the gpio pins properly declared, the functionality
> depending on these pins will not be available, but the device can still
> be used with basic functionality.
> 
> For both device tree and ACPI, the interrupt gpio pin configuration is
> read from the "irq-gpios" property and the reset pin configuration is
> read from the "reset-gpios" property. For ACPI 5.1, named properties
> can be specified using the _DSD section. This functionality will not be
> available for devices that use indexed gpio pins declared in the _CRS
> section (we need to provide backward compatibility with devices
> that do not support using the interrupt gpio pin as output).
> 
> For ACPI, the pins can be specified using ACPI 5.1:
> Device (STAC)
> {
>     Name (_HID, "GDIX1001")
>     ...
> 
>     Method (_CRS, 0, Serialized)
>     {
>         Name (RBUF, ResourceTemplate ()
>         {
>             I2cSerialBus (0x0014, ControllerInitiated, 0x00061A80,
>                 AddressingMode7Bit, "\\I2C0",
>                 0x00, ResourceConsumer, ,
>                 )
> 
>             GpioInt (Edge, ActiveHigh, Exclusive, PullNone, 0x0000,
>                 "\\I2C0", 0x00, ResourceConsumer, ,
>                  )
>                  {   // Pin list
>                      0
>                  }
> 
>             GpioIo (Exclusive, PullDown, 0x0000, 0x0000,
>                 IoRestrictionOutputOnly, "\\I2C0", 0x00,
>                 ResourceConsumer, ,
>                 )
>                 {
>                      1
>                 }
>         })
>         Return (RBUF)
>     }
> 
>     Name (_DSD,  Package ()
>     {
>         ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
>         Package ()
>         {
>             Package (2) {"irq-gpios", Package() {^STAC, 0, 0, 0 }},
>             Package (2) {"reset-gpios", Package() {^STAC, 1, 0, 0 }},
>             ...
>         }
>     }
> 
> Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
> Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
> ---
>  .../bindings/input/touchscreen/goodix.txt          |   9 ++

For the binding:

Acked-by: Rob Herring <robh@kernel.org>

>  drivers/input/touchscreen/Kconfig                  |   1 +
>  drivers/input/touchscreen/goodix.c                 | 101 +++++++++++++++++++++
>  3 files changed, 111 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt
> index 8ba98ee..c42d2ce 100644
> --- a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt
> +++ b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt
> @@ -13,6 +13,12 @@ Required properties:
>   - interrupt-parent	: Interrupt controller to which the chip is connected
>   - interrupts		: Interrupt to which the chip is connected
>  
> +Optional properties:
> +
> + - irq-gpios		: GPIO pin used for IRQ. The driver uses the
> +			  interrupt gpio pin as output to reset the device.
> + - reset-gpios		: GPIO pin used for reset
> +
>  Example:
>  
>  	i2c@00000000 {
> @@ -23,6 +29,9 @@ Example:
>  			reg = <0x5d>;
>  			interrupt-parent = <&gpio>;
>  			interrupts = <0 0>;
> +
> +			irq-gpios = <&gpio1 0 0>;
> +			reset-gpios = <&gpio1 1 0>;
>  		};
>  
>  		/* ... */
> diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
> index 2ccc522..121a0ac 100644
> --- a/drivers/input/touchscreen/Kconfig
> +++ b/drivers/input/touchscreen/Kconfig
> @@ -324,6 +324,7 @@ config TOUCHSCREEN_FUJITSU
>  config TOUCHSCREEN_GOODIX
>  	tristate "Goodix I2C touchscreen"
>  	depends on I2C
> +	depends on GPIOLIB
>  	help
>  	  Say Y here if you have the Goodix touchscreen (such as one
>  	  installed in Onda v975w tablets) connected to your
> diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
> index 56d0330..4744032 100644
> --- a/drivers/input/touchscreen/goodix.c
> +++ b/drivers/input/touchscreen/goodix.c
> @@ -16,6 +16,7 @@
>  
>  #include <linux/kernel.h>
>  #include <linux/dmi.h>
> +#include <linux/gpio.h>
>  #include <linux/i2c.h>
>  #include <linux/input.h>
>  #include <linux/input/mt.h>
> @@ -37,8 +38,13 @@ struct goodix_ts_data {
>  	unsigned int int_trigger_type;
>  	bool rotated_screen;
>  	int cfg_len;
> +	struct gpio_desc *gpiod_int;
> +	struct gpio_desc *gpiod_rst;
>  };
>  
> +#define GOODIX_GPIO_INT_NAME		"irq"
> +#define GOODIX_GPIO_RST_NAME		"reset"
> +
>  #define GOODIX_MAX_HEIGHT		4096
>  #define GOODIX_MAX_WIDTH		4096
>  #define GOODIX_INT_TRIGGER		1
> @@ -237,6 +243,88 @@ static irqreturn_t goodix_ts_irq_handler(int irq, void *dev_id)
>  	return IRQ_HANDLED;
>  }
>  
> +static int goodix_int_sync(struct goodix_ts_data *ts)
> +{
> +	int error;
> +
> +	error = gpiod_direction_output(ts->gpiod_int, 0);
> +	if (error)
> +		return error;
> +	msleep(50);				/* T5: 50ms */
> +
> +	return gpiod_direction_input(ts->gpiod_int);
> +}
> +
> +/**
> + * goodix_reset - Reset device during power on
> + *
> + * @ts: goodix_ts_data pointer
> + */
> +static int goodix_reset(struct goodix_ts_data *ts)
> +{
> +	int error;
> +
> +	/* begin select I2C slave addr */
> +	error = gpiod_direction_output(ts->gpiod_rst, 0);
> +	if (error)
> +		return error;
> +	msleep(20);				/* T2: > 10ms */
> +	/* HIGH: 0x28/0x29, LOW: 0xBA/0xBB */
> +	error = gpiod_direction_output(ts->gpiod_int, ts->client->addr == 0x14);
> +	if (error)
> +		return error;
> +	usleep_range(100, 2000);		/* T3: > 100us */
> +	error = gpiod_direction_output(ts->gpiod_rst, 1);
> +	if (error)
> +		return error;
> +	usleep_range(6000, 10000);		/* T4: > 5ms */
> +	/* end select I2C slave addr */
> +	error = gpiod_direction_input(ts->gpiod_rst);
> +	if (error)
> +		return error;
> +	return goodix_int_sync(ts);
> +}
> +
> +/**
> + * goodix_get_gpio_config - Get GPIO config from ACPI/DT
> + *
> + * @ts: goodix_ts_data pointer
> + */
> +static int goodix_get_gpio_config(struct goodix_ts_data *ts)
> +{
> +	int error;
> +	struct device *dev;
> +	struct gpio_desc *gpiod;
> +
> +	if (!ts->client)
> +		return -EINVAL;
> +	dev = &ts->client->dev;
> +
> +	/* Get the interrupt GPIO pin number */
> +	gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_INT_NAME, GPIOD_IN);
> +	if (IS_ERR(gpiod)) {
> +		error = PTR_ERR(gpiod);
> +		if (error != -EPROBE_DEFER)
> +			dev_dbg(dev, "Failed to get %s GPIO: %d\n",
> +				GOODIX_GPIO_INT_NAME, error);
> +		return error;
> +	}
> +	ts->gpiod_int = gpiod;
> +
> +	/* Get the reset line GPIO pin number */
> +	gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_RST_NAME, GPIOD_IN);
> +	if (IS_ERR(gpiod)) {
> +		error = PTR_ERR(gpiod);
> +		if (error != -EPROBE_DEFER)
> +			dev_dbg(dev, "Failed to get %s GPIO: %d\n",
> +				GOODIX_GPIO_RST_NAME, error);
> +		return error;
> +	}
> +	ts->gpiod_rst = gpiod;
> +
> +	return 0;
> +}
> +
>  /**
>   * goodix_read_config - Read the embedded configuration of the panel
>   *
> @@ -405,6 +493,19 @@ static int goodix_ts_probe(struct i2c_client *client,
>  	ts->client = client;
>  	i2c_set_clientdata(client, ts);
>  
> +	error = goodix_get_gpio_config(ts);
> +	if (error)
> +		return error;
> +
> +	if (ts->gpiod_int && ts->gpiod_rst) {
> +		/* reset the controller */
> +		error = goodix_reset(ts);
> +		if (error) {
> +			dev_err(&client->dev, "Controller reset failed.\n");
> +			return error;
> +		}
> +	}
> +
>  	error = goodix_i2c_test(client);
>  	if (error) {
>  		dev_err(&client->dev, "I2C communication failure: %d\n", error);
> -- 
> 1.9.1
> 
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Bastien Nocera Nov. 23, 2015, 4:31 p.m. UTC | #4
On Thu, 2015-11-19 at 14:26 +0200, Irina Tirdea wrote:
> 
<snip>
> Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
> Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>

Works on the WinBook TW100

Acked-by: Bastien Nocera <hadess@hadess.net>
Tested-by: Bastien Nocera <hadess@hadess.net>
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Aleksei Mamlin Dec. 8, 2015, 12:04 p.m. UTC | #5
On Thu, 19 Nov 2015 14:26:35 +0200
Irina Tirdea <irina.tirdea@intel.com> wrote:

> After power on, it is recommended that the driver resets the device.
> The reset procedure timing is described in the datasheet and is used
> at device init (before writing device configuration) and
> for power management. It is a sequence of setting the interrupt
> and reset pins high/low at specific timing intervals. This procedure
> also includes setting the slave address to the one specified in the
> ACPI/device tree.
> 
> This is based on Goodix datasheets for GT911 and GT9271 and on Goodix
> driver gt9xx.c for Android (publicly available in Android kernel
> trees for various devices).
> 
> For reset the driver needs to control the interrupt and
> reset gpio pins (configured through ACPI/device tree). For devices
> that do not have the gpio pins properly declared, the functionality
> depending on these pins will not be available, but the device can still
> be used with basic functionality.
> 
> For both device tree and ACPI, the interrupt gpio pin configuration is
> read from the "irq-gpios" property and the reset pin configuration is
> read from the "reset-gpios" property. For ACPI 5.1, named properties
> can be specified using the _DSD section. This functionality will not be
> available for devices that use indexed gpio pins declared in the _CRS
> section (we need to provide backward compatibility with devices
> that do not support using the interrupt gpio pin as output).
> 
> For ACPI, the pins can be specified using ACPI 5.1:
> Device (STAC)
> {
>     Name (_HID, "GDIX1001")
>     ...
> 
>     Method (_CRS, 0, Serialized)
>     {
>         Name (RBUF, ResourceTemplate ()
>         {
>             I2cSerialBus (0x0014, ControllerInitiated, 0x00061A80,
>                 AddressingMode7Bit, "\\I2C0",
>                 0x00, ResourceConsumer, ,
>                 )
> 
>             GpioInt (Edge, ActiveHigh, Exclusive, PullNone, 0x0000,
>                 "\\I2C0", 0x00, ResourceConsumer, ,
>                  )
>                  {   // Pin list
>                      0
>                  }
> 
>             GpioIo (Exclusive, PullDown, 0x0000, 0x0000,
>                 IoRestrictionOutputOnly, "\\I2C0", 0x00,
>                 ResourceConsumer, ,
>                 )
>                 {
>                      1
>                 }
>         })
>         Return (RBUF)
>     }
> 
>     Name (_DSD,  Package ()
>     {
>         ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
>         Package ()
>         {
>             Package (2) {"irq-gpios", Package() {^STAC, 0, 0, 0 }},
>             Package (2) {"reset-gpios", Package() {^STAC, 1, 0, 0 }},
>             ...
>         }
>     }
> 
> Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
> Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>

Works on the Wexler TAB7200

Tested-by: Aleksei Mamlin <mamlinav@gmail.com>

> ---
>  .../bindings/input/touchscreen/goodix.txt          |   9 ++
>  drivers/input/touchscreen/Kconfig                  |   1 +
>  drivers/input/touchscreen/goodix.c                 | 101 +++++++++++++++++++++
>  3 files changed, 111 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt
> index 8ba98ee..c42d2ce 100644
> --- a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt
> +++ b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt
> @@ -13,6 +13,12 @@ Required properties:
>   - interrupt-parent	: Interrupt controller to which the chip is connected
>   - interrupts		: Interrupt to which the chip is connected
>  
> +Optional properties:
> +
> + - irq-gpios		: GPIO pin used for IRQ. The driver uses the
> +			  interrupt gpio pin as output to reset the device.
> + - reset-gpios		: GPIO pin used for reset
> +
>  Example:
>  
>  	i2c@00000000 {
> @@ -23,6 +29,9 @@ Example:
>  			reg = <0x5d>;
>  			interrupt-parent = <&gpio>;
>  			interrupts = <0 0>;
> +
> +			irq-gpios = <&gpio1 0 0>;
> +			reset-gpios = <&gpio1 1 0>;
>  		};
>  
>  		/* ... */
> diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
> index 2ccc522..121a0ac 100644
> --- a/drivers/input/touchscreen/Kconfig
> +++ b/drivers/input/touchscreen/Kconfig
> @@ -324,6 +324,7 @@ config TOUCHSCREEN_FUJITSU
>  config TOUCHSCREEN_GOODIX
>  	tristate "Goodix I2C touchscreen"
>  	depends on I2C
> +	depends on GPIOLIB
>  	help
>  	  Say Y here if you have the Goodix touchscreen (such as one
>  	  installed in Onda v975w tablets) connected to your
> diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
> index 56d0330..4744032 100644
> --- a/drivers/input/touchscreen/goodix.c
> +++ b/drivers/input/touchscreen/goodix.c
> @@ -16,6 +16,7 @@
>  
>  #include <linux/kernel.h>
>  #include <linux/dmi.h>
> +#include <linux/gpio.h>
>  #include <linux/i2c.h>
>  #include <linux/input.h>
>  #include <linux/input/mt.h>
> @@ -37,8 +38,13 @@ struct goodix_ts_data {
>  	unsigned int int_trigger_type;
>  	bool rotated_screen;
>  	int cfg_len;
> +	struct gpio_desc *gpiod_int;
> +	struct gpio_desc *gpiod_rst;
>  };
>  
> +#define GOODIX_GPIO_INT_NAME		"irq"
> +#define GOODIX_GPIO_RST_NAME		"reset"
> +
>  #define GOODIX_MAX_HEIGHT		4096
>  #define GOODIX_MAX_WIDTH		4096
>  #define GOODIX_INT_TRIGGER		1
> @@ -237,6 +243,88 @@ static irqreturn_t goodix_ts_irq_handler(int irq, void *dev_id)
>  	return IRQ_HANDLED;
>  }
>  
> +static int goodix_int_sync(struct goodix_ts_data *ts)
> +{
> +	int error;
> +
> +	error = gpiod_direction_output(ts->gpiod_int, 0);
> +	if (error)
> +		return error;
> +	msleep(50);				/* T5: 50ms */
> +
> +	return gpiod_direction_input(ts->gpiod_int);
> +}
> +
> +/**
> + * goodix_reset - Reset device during power on
> + *
> + * @ts: goodix_ts_data pointer
> + */
> +static int goodix_reset(struct goodix_ts_data *ts)
> +{
> +	int error;
> +
> +	/* begin select I2C slave addr */
> +	error = gpiod_direction_output(ts->gpiod_rst, 0);
> +	if (error)
> +		return error;
> +	msleep(20);				/* T2: > 10ms */
> +	/* HIGH: 0x28/0x29, LOW: 0xBA/0xBB */
> +	error = gpiod_direction_output(ts->gpiod_int, ts->client->addr == 0x14);
> +	if (error)
> +		return error;
> +	usleep_range(100, 2000);		/* T3: > 100us */
> +	error = gpiod_direction_output(ts->gpiod_rst, 1);
> +	if (error)
> +		return error;
> +	usleep_range(6000, 10000);		/* T4: > 5ms */
> +	/* end select I2C slave addr */
> +	error = gpiod_direction_input(ts->gpiod_rst);
> +	if (error)
> +		return error;
> +	return goodix_int_sync(ts);
> +}
> +
> +/**
> + * goodix_get_gpio_config - Get GPIO config from ACPI/DT
> + *
> + * @ts: goodix_ts_data pointer
> + */
> +static int goodix_get_gpio_config(struct goodix_ts_data *ts)
> +{
> +	int error;
> +	struct device *dev;
> +	struct gpio_desc *gpiod;
> +
> +	if (!ts->client)
> +		return -EINVAL;
> +	dev = &ts->client->dev;
> +
> +	/* Get the interrupt GPIO pin number */
> +	gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_INT_NAME, GPIOD_IN);
> +	if (IS_ERR(gpiod)) {
> +		error = PTR_ERR(gpiod);
> +		if (error != -EPROBE_DEFER)
> +			dev_dbg(dev, "Failed to get %s GPIO: %d\n",
> +				GOODIX_GPIO_INT_NAME, error);
> +		return error;
> +	}
> +	ts->gpiod_int = gpiod;
> +
> +	/* Get the reset line GPIO pin number */
> +	gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_RST_NAME, GPIOD_IN);
> +	if (IS_ERR(gpiod)) {
> +		error = PTR_ERR(gpiod);
> +		if (error != -EPROBE_DEFER)
> +			dev_dbg(dev, "Failed to get %s GPIO: %d\n",
> +				GOODIX_GPIO_RST_NAME, error);
> +		return error;
> +	}
> +	ts->gpiod_rst = gpiod;
> +
> +	return 0;
> +}
> +
>  /**
>   * goodix_read_config - Read the embedded configuration of the panel
>   *
> @@ -405,6 +493,19 @@ static int goodix_ts_probe(struct i2c_client *client,
>  	ts->client = client;
>  	i2c_set_clientdata(client, ts);
>  
> +	error = goodix_get_gpio_config(ts);
> +	if (error)
> +		return error;
> +
> +	if (ts->gpiod_int && ts->gpiod_rst) {
> +		/* reset the controller */
> +		error = goodix_reset(ts);
> +		if (error) {
> +			dev_err(&client->dev, "Controller reset failed.\n");
> +			return error;
> +		}
> +	}
> +
>  	error = goodix_i2c_test(client);
>  	if (error) {
>  		dev_err(&client->dev, "I2C communication failure: %d\n", error);
> -- 
> 1.9.1
>
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt
index 8ba98ee..c42d2ce 100644
--- a/Documentation/devicetree/bindings/input/touchscreen/goodix.txt
+++ b/Documentation/devicetree/bindings/input/touchscreen/goodix.txt
@@ -13,6 +13,12 @@  Required properties:
  - interrupt-parent	: Interrupt controller to which the chip is connected
  - interrupts		: Interrupt to which the chip is connected
 
+Optional properties:
+
+ - irq-gpios		: GPIO pin used for IRQ. The driver uses the
+			  interrupt gpio pin as output to reset the device.
+ - reset-gpios		: GPIO pin used for reset
+
 Example:
 
 	i2c@00000000 {
@@ -23,6 +29,9 @@  Example:
 			reg = <0x5d>;
 			interrupt-parent = <&gpio>;
 			interrupts = <0 0>;
+
+			irq-gpios = <&gpio1 0 0>;
+			reset-gpios = <&gpio1 1 0>;
 		};
 
 		/* ... */
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 2ccc522..121a0ac 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -324,6 +324,7 @@  config TOUCHSCREEN_FUJITSU
 config TOUCHSCREEN_GOODIX
 	tristate "Goodix I2C touchscreen"
 	depends on I2C
+	depends on GPIOLIB
 	help
 	  Say Y here if you have the Goodix touchscreen (such as one
 	  installed in Onda v975w tablets) connected to your
diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index 56d0330..4744032 100644
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -16,6 +16,7 @@ 
 
 #include <linux/kernel.h>
 #include <linux/dmi.h>
+#include <linux/gpio.h>
 #include <linux/i2c.h>
 #include <linux/input.h>
 #include <linux/input/mt.h>
@@ -37,8 +38,13 @@  struct goodix_ts_data {
 	unsigned int int_trigger_type;
 	bool rotated_screen;
 	int cfg_len;
+	struct gpio_desc *gpiod_int;
+	struct gpio_desc *gpiod_rst;
 };
 
+#define GOODIX_GPIO_INT_NAME		"irq"
+#define GOODIX_GPIO_RST_NAME		"reset"
+
 #define GOODIX_MAX_HEIGHT		4096
 #define GOODIX_MAX_WIDTH		4096
 #define GOODIX_INT_TRIGGER		1
@@ -237,6 +243,88 @@  static irqreturn_t goodix_ts_irq_handler(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static int goodix_int_sync(struct goodix_ts_data *ts)
+{
+	int error;
+
+	error = gpiod_direction_output(ts->gpiod_int, 0);
+	if (error)
+		return error;
+	msleep(50);				/* T5: 50ms */
+
+	return gpiod_direction_input(ts->gpiod_int);
+}
+
+/**
+ * goodix_reset - Reset device during power on
+ *
+ * @ts: goodix_ts_data pointer
+ */
+static int goodix_reset(struct goodix_ts_data *ts)
+{
+	int error;
+
+	/* begin select I2C slave addr */
+	error = gpiod_direction_output(ts->gpiod_rst, 0);
+	if (error)
+		return error;
+	msleep(20);				/* T2: > 10ms */
+	/* HIGH: 0x28/0x29, LOW: 0xBA/0xBB */
+	error = gpiod_direction_output(ts->gpiod_int, ts->client->addr == 0x14);
+	if (error)
+		return error;
+	usleep_range(100, 2000);		/* T3: > 100us */
+	error = gpiod_direction_output(ts->gpiod_rst, 1);
+	if (error)
+		return error;
+	usleep_range(6000, 10000);		/* T4: > 5ms */
+	/* end select I2C slave addr */
+	error = gpiod_direction_input(ts->gpiod_rst);
+	if (error)
+		return error;
+	return goodix_int_sync(ts);
+}
+
+/**
+ * goodix_get_gpio_config - Get GPIO config from ACPI/DT
+ *
+ * @ts: goodix_ts_data pointer
+ */
+static int goodix_get_gpio_config(struct goodix_ts_data *ts)
+{
+	int error;
+	struct device *dev;
+	struct gpio_desc *gpiod;
+
+	if (!ts->client)
+		return -EINVAL;
+	dev = &ts->client->dev;
+
+	/* Get the interrupt GPIO pin number */
+	gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_INT_NAME, GPIOD_IN);
+	if (IS_ERR(gpiod)) {
+		error = PTR_ERR(gpiod);
+		if (error != -EPROBE_DEFER)
+			dev_dbg(dev, "Failed to get %s GPIO: %d\n",
+				GOODIX_GPIO_INT_NAME, error);
+		return error;
+	}
+	ts->gpiod_int = gpiod;
+
+	/* Get the reset line GPIO pin number */
+	gpiod = devm_gpiod_get_optional(dev, GOODIX_GPIO_RST_NAME, GPIOD_IN);
+	if (IS_ERR(gpiod)) {
+		error = PTR_ERR(gpiod);
+		if (error != -EPROBE_DEFER)
+			dev_dbg(dev, "Failed to get %s GPIO: %d\n",
+				GOODIX_GPIO_RST_NAME, error);
+		return error;
+	}
+	ts->gpiod_rst = gpiod;
+
+	return 0;
+}
+
 /**
  * goodix_read_config - Read the embedded configuration of the panel
  *
@@ -405,6 +493,19 @@  static int goodix_ts_probe(struct i2c_client *client,
 	ts->client = client;
 	i2c_set_clientdata(client, ts);
 
+	error = goodix_get_gpio_config(ts);
+	if (error)
+		return error;
+
+	if (ts->gpiod_int && ts->gpiod_rst) {
+		/* reset the controller */
+		error = goodix_reset(ts);
+		if (error) {
+			dev_err(&client->dev, "Controller reset failed.\n");
+			return error;
+		}
+	}
+
 	error = goodix_i2c_test(client);
 	if (error) {
 		dev_err(&client->dev, "I2C communication failure: %d\n", error);