diff mbox series

[v4,2/5] gpio: Add support for Intel LJCA USB GPIO driver

Message ID 20230309071100.2856899-3-xiang.ye@intel.com
State Superseded
Headers show
Series Add Intel LJCA device driver | expand

Commit Message

Ye Xiang March 9, 2023, 7:10 a.m. UTC 
This patch implements the GPIO function of Intel USB-I2C/GPIO/SPI adapter
device named "La Jolla Cove Adapter" (LJCA). It communicate with LJCA
GPIO module with specific protocol through interfaces exported by LJCA USB
driver.

Signed-off-by: Ye Xiang <xiang.ye@intel.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
 drivers/gpio/Kconfig     |  12 ++
 drivers/gpio/Makefile    |   1 +
 drivers/gpio/gpio-ljca.c | 454 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 467 insertions(+)
 create mode 100644 drivers/gpio/gpio-ljca.c

Comments

Ye Xiang March 10, 2023, 5:01 a.m. UTC | #1 
On Thu, Mar 09, 2023 at 02:40:10PM +0100, Oliver Neukum wrote:
> 
> 
> On 09.03.23 08:10, Ye Xiang wrote:
> 
> > +#define LJCA_GPIO_BUF_SIZE 60
> > +struct ljca_gpio_dev {
> > +	struct platform_device *pdev;
> > +	struct gpio_chip gc;
> > +	struct ljca_gpio_info *gpio_info;
> > +	DECLARE_BITMAP(unmasked_irqs, LJCA_MAX_GPIO_NUM);
> > +	DECLARE_BITMAP(enabled_irqs, LJCA_MAX_GPIO_NUM);
> > +	DECLARE_BITMAP(reenable_irqs, LJCA_MAX_GPIO_NUM);
> > +	u8 *connect_mode;
> > +	/* mutex to protect irq bus */
> > +	struct mutex irq_lock;
> > +	struct work_struct work;
> > +	/* lock to protect package transfer to Hardware */
> > +	struct mutex trans_lock;
> > +
> > +	u8 obuf[LJCA_GPIO_BUF_SIZE];
> > +	u8 ibuf[LJCA_GPIO_BUF_SIZE];
> 
> And here we have a violation of DMA coherency rules.
> Basically you cannot embed buffers into other data structures
> if they can be subject to DMA.
But obuf and ibuf does not used to do DMA transfer here.
It is actually copied from or to ljca buffer to do URB transfer.
Should it still need to follow the DMA coherency rules?
> 
> 
> 
> 
> > +static int ljca_gpio_remove(struct platform_device *pdev)
> > +{
> > +	struct ljca_gpio_dev *ljca_gpio = platform_get_drvdata(pdev);
> > +
> > +	gpiochip_remove(&ljca_gpio->gc);
> > +	ljca_unregister_event_cb(ljca_gpio->gpio_info->ljca);
> > +	mutex_destroy(&ljca_gpio->irq_lock);
> > +	mutex_destroy(&ljca_gpio->trans_lock);
> 
> At this time, what has made sure that no work is scheduled?
Can't make sure of that. Could Adding cancel_work_sync(&ljca_gpio->work) before
mutex_destroy can address it?
> 
> > +	return 0;
> > +}
> 
> 

--
Thanks
Ye Xiang
Krzysztof Kozlowski March 11, 2023, 12:13 p.m. UTC | #2 
On 09/03/2023 08:10, Ye Xiang wrote:
> This patch implements the GPIO function of Intel USB-I2C/GPIO/SPI adapter
> device named "La Jolla Cove Adapter" (LJCA). It communicate with LJCA
> GPIO module with specific protocol through interfaces exported by LJCA USB
> driver.
> 
> Signed-off-by: Ye Xiang <xiang.ye@intel.com>
> Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>  drivers/gpio/Kconfig     |  12 ++
>  drivers/gpio/Makefile    |   1 +
>  drivers/gpio/gpio-ljca.c | 454 +++++++++++++++++++++++++++++++++++++++
>  3 files changed, 467 insertions(+)
>  create mode 100644 drivers/gpio/gpio-ljca.c
> 
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index 13be729710f2..8be697f9f621 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -1253,6 +1253,18 @@ config GPIO_KEMPLD
>  	  This driver can also be built as a module. If so, the module will be
>  	  called gpio-kempld.
>  
> +config GPIO_LJCA
> +	tristate "INTEL La Jolla Cove Adapter GPIO support"
> +	depends on MFD_LJCA
> +	select GPIOLIB_IRQCHIP
> +	default MFD_LJCA
> +	help
> +	  Select this option to enable GPIO driver for the INTEL
> +	  La Jolla Cove Adapter (LJCA) board.
> +
> +	  This driver can also be built as a module. If so, the module
> +	  will be called gpio-ljca.
> +
>  config GPIO_LP3943
>  	tristate "TI/National Semiconductor LP3943 GPIO expander"
>  	depends on MFD_LP3943
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index c048ba003367..eb59524d18c0 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -77,6 +77,7 @@ obj-$(CONFIG_GPIO_IXP4XX)		+= gpio-ixp4xx.o
>  obj-$(CONFIG_GPIO_JANZ_TTL)		+= gpio-janz-ttl.o
>  obj-$(CONFIG_GPIO_KEMPLD)		+= gpio-kempld.o
>  obj-$(CONFIG_GPIO_LATCH)		+= gpio-latch.o
> +obj-$(CONFIG_GPIO_LJCA) 		+= gpio-ljca.o
>  obj-$(CONFIG_GPIO_LOGICVC)		+= gpio-logicvc.o
>  obj-$(CONFIG_GPIO_LOONGSON1)		+= gpio-loongson1.o
>  obj-$(CONFIG_GPIO_LOONGSON)		+= gpio-loongson.o
> diff --git a/drivers/gpio/gpio-ljca.c b/drivers/gpio/gpio-ljca.c
> new file mode 100644
> index 000000000000..87863f0230f5
> --- /dev/null
> +++ b/drivers/gpio/gpio-ljca.c
> @@ -0,0 +1,454 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Intel La Jolla Cove Adapter USB-GPIO driver
> + *
> + * Copyright (c) 2023, Intel Corporation.
> + */
> +
> +#include <linux/acpi.h>
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/dev_printk.h>
> +#include <linux/gpio/driver.h>
> +#include <linux/irq.h>
> +#include <linux/kernel.h>
> +#include <linux/kref.h>
> +#include <linux/mfd/ljca.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/types.h>
> +
> +/* GPIO commands */
> +#define LJCA_GPIO_CONFIG	1
> +#define LJCA_GPIO_READ		2
> +#define LJCA_GPIO_WRITE		3
> +#define LJCA_GPIO_INT_EVENT	4
> +#define LJCA_GPIO_INT_MASK	5
> +#define LJCA_GPIO_INT_UNMASK	6
> +
> +#define LJCA_GPIO_CONF_DISABLE		BIT(0)
> +#define LJCA_GPIO_CONF_INPUT		BIT(1)
> +#define LJCA_GPIO_CONF_OUTPUT		BIT(2)
> +#define LJCA_GPIO_CONF_PULLUP		BIT(3)
> +#define LJCA_GPIO_CONF_PULLDOWN		BIT(4)
> +#define LJCA_GPIO_CONF_DEFAULT		BIT(5)
> +#define LJCA_GPIO_CONF_INTERRUPT	BIT(6)
> +#define LJCA_GPIO_INT_TYPE		BIT(7)
> +
> +#define LJCA_GPIO_CONF_EDGE	FIELD_PREP(LJCA_GPIO_INT_TYPE, 1)
> +#define LJCA_GPIO_CONF_LEVEL	FIELD_PREP(LJCA_GPIO_INT_TYPE, 0)
> +
> +/* Intentional overlap with PULLUP / PULLDOWN */
> +#define LJCA_GPIO_CONF_SET	BIT(3)
> +#define LJCA_GPIO_CONF_CLR	BIT(4)
> +
> +struct gpio_op {
> +	u8 index;
> +	u8 value;
> +} __packed;
> +
> +struct gpio_packet {
> +	u8 num;
> +	struct gpio_op item[];
> +} __packed;
> +
> +#define LJCA_GPIO_BUF_SIZE 60
> +struct ljca_gpio_dev {
> +	struct platform_device *pdev;
> +	struct gpio_chip gc;
> +	struct ljca_gpio_info *gpio_info;
> +	DECLARE_BITMAP(unmasked_irqs, LJCA_MAX_GPIO_NUM);
> +	DECLARE_BITMAP(enabled_irqs, LJCA_MAX_GPIO_NUM);
> +	DECLARE_BITMAP(reenable_irqs, LJCA_MAX_GPIO_NUM);
> +	u8 *connect_mode;
> +	/* mutex to protect irq bus */
> +	struct mutex irq_lock;
> +	struct work_struct work;
> +	/* lock to protect package transfer to Hardware */
> +	struct mutex trans_lock;
> +
> +	u8 obuf[LJCA_GPIO_BUF_SIZE];
> +	u8 ibuf[LJCA_GPIO_BUF_SIZE];
> +};
> +
> +static int gpio_config(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id, u8 config)
> +{
> +	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
> +	int ret;
> +
> +	mutex_lock(&ljca_gpio->trans_lock);
> +	packet->item[0].index = gpio_id;
> +	packet->item[0].value = config | ljca_gpio->connect_mode[gpio_id];
> +	packet->num = 1;
> +
> +	ret = ljca_transfer(ljca_gpio->gpio_info->ljca, LJCA_GPIO_CONFIG, packet,
> +			    struct_size(packet, item, packet->num), NULL, NULL);
> +	mutex_unlock(&ljca_gpio->trans_lock);
> +	return ret;
> +}
> +
> +static int ljca_gpio_read(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id)
> +{
> +	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
> +	struct gpio_packet *ack_packet = (struct gpio_packet *)ljca_gpio->ibuf;
> +	unsigned int ibuf_len = LJCA_GPIO_BUF_SIZE;
> +	int ret;
> +
> +	mutex_lock(&ljca_gpio->trans_lock);
> +	packet->num = 1;
> +	packet->item[0].index = gpio_id;
> +	ret = ljca_transfer(ljca_gpio->gpio_info->ljca, LJCA_GPIO_READ, packet,
> +			    struct_size(packet, item, packet->num), ljca_gpio->ibuf, &ibuf_len);
> +	if (ret)
> +		goto out_unlock;
> +
> +	if (!ibuf_len || ack_packet->num != packet->num) {
> +		dev_err(&ljca_gpio->pdev->dev, "failed gpio_id:%u %u", gpio_id, ack_packet->num);
> +		ret = -EIO;
> +	}
> +
> +out_unlock:
> +	mutex_unlock(&ljca_gpio->trans_lock);
> +	if (ret)
> +		return ret;
> +	return ack_packet->item[0].value > 0;
> +}
> +
> +static int ljca_gpio_write(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id,
> +			   int value)
> +{
> +	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
> +	int ret;
> +
> +	mutex_lock(&ljca_gpio->trans_lock);
> +	packet->num = 1;
> +	packet->item[0].index = gpio_id;
> +	packet->item[0].value = value & 1;
> +
> +	ret = ljca_transfer(ljca_gpio->gpio_info->ljca, LJCA_GPIO_WRITE, packet,
> +			    struct_size(packet, item, packet->num), NULL, NULL);
> +	mutex_unlock(&ljca_gpio->trans_lock);

Everywhere you have unusual coding pattern around return. There is
almost always line break before return. Adjust to the kernel style.

> +	return ret;
> +}

(...)

> +
> +#define LJCA_GPIO_DRV_NAME "ljca-gpio"
> +static const struct platform_device_id ljca_gpio_id[] = {
> +	{ LJCA_GPIO_DRV_NAME, 0 },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(platform, ljca_gpio_id);

ljca_gpio_id is unused (except module autoloading). How do you bind your
devices?

> +
> +static struct platform_driver ljca_gpio_driver = {
> +	.driver.name = LJCA_GPIO_DRV_NAME,
> +	.probe = ljca_gpio_probe,
> +	.remove = ljca_gpio_remove,



Best regards,
Krzysztof
Ye Xiang March 12, 2023, 3:40 p.m. UTC | #3 
Hi Krzysztof,

Thanks for your review.
On Sat, Mar 11, 2023 at 01:13:30PM +0100, Krzysztof Kozlowski wrote:
> On 09/03/2023 08:10, Ye Xiang wrote:
> > This patch implements the GPIO function of Intel USB-I2C/GPIO/SPI adapter
> > device named "La Jolla Cove Adapter" (LJCA). It communicate with LJCA
> > GPIO module with specific protocol through interfaces exported by LJCA USB
> > driver.
> > 
> > Signed-off-by: Ye Xiang <xiang.ye@intel.com>
> > Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> > Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> > ---
> >  drivers/gpio/Kconfig     |  12 ++
> >  drivers/gpio/Makefile    |   1 +
> >  drivers/gpio/gpio-ljca.c | 454 +++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 467 insertions(+)
> >  create mode 100644 drivers/gpio/gpio-ljca.c
> > 
> > diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> > index 13be729710f2..8be697f9f621 100644
> > --- a/drivers/gpio/Kconfig
> > +++ b/drivers/gpio/Kconfig
> > @@ -1253,6 +1253,18 @@ config GPIO_KEMPLD
> >  	  This driver can also be built as a module. If so, the module will be
> >  	  called gpio-kempld.
> >  
> > +config GPIO_LJCA
> > +	tristate "INTEL La Jolla Cove Adapter GPIO support"
> > +	depends on MFD_LJCA
> > +	select GPIOLIB_IRQCHIP
> > +	default MFD_LJCA
> > +	help
> > +	  Select this option to enable GPIO driver for the INTEL
> > +	  La Jolla Cove Adapter (LJCA) board.
> > +
> > +	  This driver can also be built as a module. If so, the module
> > +	  will be called gpio-ljca.
> > +
> >  config GPIO_LP3943
> >  	tristate "TI/National Semiconductor LP3943 GPIO expander"
> >  	depends on MFD_LP3943
> > diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> > index c048ba003367..eb59524d18c0 100644
> > --- a/drivers/gpio/Makefile
> > +++ b/drivers/gpio/Makefile
> > @@ -77,6 +77,7 @@ obj-$(CONFIG_GPIO_IXP4XX)		+= gpio-ixp4xx.o
> >  obj-$(CONFIG_GPIO_JANZ_TTL)		+= gpio-janz-ttl.o
> >  obj-$(CONFIG_GPIO_KEMPLD)		+= gpio-kempld.o
> >  obj-$(CONFIG_GPIO_LATCH)		+= gpio-latch.o
> > +obj-$(CONFIG_GPIO_LJCA) 		+= gpio-ljca.o
> >  obj-$(CONFIG_GPIO_LOGICVC)		+= gpio-logicvc.o
> >  obj-$(CONFIG_GPIO_LOONGSON1)		+= gpio-loongson1.o
> >  obj-$(CONFIG_GPIO_LOONGSON)		+= gpio-loongson.o
> > diff --git a/drivers/gpio/gpio-ljca.c b/drivers/gpio/gpio-ljca.c
> > new file mode 100644
> > index 000000000000..87863f0230f5
> > --- /dev/null
> > +++ b/drivers/gpio/gpio-ljca.c
> > @@ -0,0 +1,454 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * Intel La Jolla Cove Adapter USB-GPIO driver
> > + *
> > + * Copyright (c) 2023, Intel Corporation.
> > + */
> > +
> > +#include <linux/acpi.h>
> > +#include <linux/bitfield.h>
> > +#include <linux/bitops.h>
> > +#include <linux/dev_printk.h>
> > +#include <linux/gpio/driver.h>
> > +#include <linux/irq.h>
> > +#include <linux/kernel.h>
> > +#include <linux/kref.h>
> > +#include <linux/mfd/ljca.h>
> > +#include <linux/module.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/slab.h>
> > +#include <linux/types.h>
> > +
> > +/* GPIO commands */
> > +#define LJCA_GPIO_CONFIG	1
> > +#define LJCA_GPIO_READ		2
> > +#define LJCA_GPIO_WRITE		3
> > +#define LJCA_GPIO_INT_EVENT	4
> > +#define LJCA_GPIO_INT_MASK	5
> > +#define LJCA_GPIO_INT_UNMASK	6
> > +
> > +#define LJCA_GPIO_CONF_DISABLE		BIT(0)
> > +#define LJCA_GPIO_CONF_INPUT		BIT(1)
> > +#define LJCA_GPIO_CONF_OUTPUT		BIT(2)
> > +#define LJCA_GPIO_CONF_PULLUP		BIT(3)
> > +#define LJCA_GPIO_CONF_PULLDOWN		BIT(4)
> > +#define LJCA_GPIO_CONF_DEFAULT		BIT(5)
> > +#define LJCA_GPIO_CONF_INTERRUPT	BIT(6)
> > +#define LJCA_GPIO_INT_TYPE		BIT(7)
> > +
> > +#define LJCA_GPIO_CONF_EDGE	FIELD_PREP(LJCA_GPIO_INT_TYPE, 1)
> > +#define LJCA_GPIO_CONF_LEVEL	FIELD_PREP(LJCA_GPIO_INT_TYPE, 0)
> > +
> > +/* Intentional overlap with PULLUP / PULLDOWN */
> > +#define LJCA_GPIO_CONF_SET	BIT(3)
> > +#define LJCA_GPIO_CONF_CLR	BIT(4)
> > +
> > +struct gpio_op {
> > +	u8 index;
> > +	u8 value;
> > +} __packed;
> > +
> > +struct gpio_packet {
> > +	u8 num;
> > +	struct gpio_op item[];
> > +} __packed;
> > +
> > +#define LJCA_GPIO_BUF_SIZE 60
> > +struct ljca_gpio_dev {
> > +	struct platform_device *pdev;
> > +	struct gpio_chip gc;
> > +	struct ljca_gpio_info *gpio_info;
> > +	DECLARE_BITMAP(unmasked_irqs, LJCA_MAX_GPIO_NUM);
> > +	DECLARE_BITMAP(enabled_irqs, LJCA_MAX_GPIO_NUM);
> > +	DECLARE_BITMAP(reenable_irqs, LJCA_MAX_GPIO_NUM);
> > +	u8 *connect_mode;
> > +	/* mutex to protect irq bus */
> > +	struct mutex irq_lock;
> > +	struct work_struct work;
> > +	/* lock to protect package transfer to Hardware */
> > +	struct mutex trans_lock;
> > +
> > +	u8 obuf[LJCA_GPIO_BUF_SIZE];
> > +	u8 ibuf[LJCA_GPIO_BUF_SIZE];
> > +};
> > +
> > +static int gpio_config(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id, u8 config)
> > +{
> > +	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
> > +	int ret;
> > +
> > +	mutex_lock(&ljca_gpio->trans_lock);
> > +	packet->item[0].index = gpio_id;
> > +	packet->item[0].value = config | ljca_gpio->connect_mode[gpio_id];
> > +	packet->num = 1;
> > +
> > +	ret = ljca_transfer(ljca_gpio->gpio_info->ljca, LJCA_GPIO_CONFIG, packet,
> > +			    struct_size(packet, item, packet->num), NULL, NULL);
> > +	mutex_unlock(&ljca_gpio->trans_lock);
> > +	return ret;
> > +}
> > +
> > +static int ljca_gpio_read(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id)
> > +{
> > +	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
> > +	struct gpio_packet *ack_packet = (struct gpio_packet *)ljca_gpio->ibuf;
> > +	unsigned int ibuf_len = LJCA_GPIO_BUF_SIZE;
> > +	int ret;
> > +
> > +	mutex_lock(&ljca_gpio->trans_lock);
> > +	packet->num = 1;
> > +	packet->item[0].index = gpio_id;
> > +	ret = ljca_transfer(ljca_gpio->gpio_info->ljca, LJCA_GPIO_READ, packet,
> > +			    struct_size(packet, item, packet->num), ljca_gpio->ibuf, &ibuf_len);
> > +	if (ret)
> > +		goto out_unlock;
> > +
> > +	if (!ibuf_len || ack_packet->num != packet->num) {
> > +		dev_err(&ljca_gpio->pdev->dev, "failed gpio_id:%u %u", gpio_id, ack_packet->num);
> > +		ret = -EIO;
> > +	}
> > +
> > +out_unlock:
> > +	mutex_unlock(&ljca_gpio->trans_lock);
> > +	if (ret)
> > +		return ret;
> > +	return ack_packet->item[0].value > 0;
> > +}
> > +
> > +static int ljca_gpio_write(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id,
> > +			   int value)
> > +{
> > +	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
> > +	int ret;
> > +
> > +	mutex_lock(&ljca_gpio->trans_lock);
> > +	packet->num = 1;
> > +	packet->item[0].index = gpio_id;
> > +	packet->item[0].value = value & 1;
> > +
> > +	ret = ljca_transfer(ljca_gpio->gpio_info->ljca, LJCA_GPIO_WRITE, packet,
> > +			    struct_size(packet, item, packet->num), NULL, NULL);
> > +	mutex_unlock(&ljca_gpio->trans_lock);
> 
> Everywhere you have unusual coding pattern around return. There is
> almost always line break before return. Adjust to the kernel style.
Got it. Will add a blank line before return.
> 
> > +	return ret;
> > +}
> 
> (...)
> 
> > +
> > +#define LJCA_GPIO_DRV_NAME "ljca-gpio"
> > +static const struct platform_device_id ljca_gpio_id[] = {
> > +	{ LJCA_GPIO_DRV_NAME, 0 },
> > +	{ /* sentinel */ }
> > +};
> > +MODULE_DEVICE_TABLE(platform, ljca_gpio_id);
> 
> ljca_gpio_id is unused (except module autoloading). How do you bind your
> devices?
driver.name = LJCA_GPIO_DRV_NAME, this driver name is used to bind
with devices. 
> > +
> > +static struct platform_driver ljca_gpio_driver = {
> > +	.driver.name = LJCA_GPIO_DRV_NAME,
> > +	.probe = ljca_gpio_probe,
> > +	.remove = ljca_gpio_remove,
> 
> 
--
Thanks
Ye Xiang
diff mbox series

Patch

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 13be729710f2..8be697f9f621 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1253,6 +1253,18 @@  config GPIO_KEMPLD
 	  This driver can also be built as a module. If so, the module will be
 	  called gpio-kempld.
 
+config GPIO_LJCA
+	tristate "INTEL La Jolla Cove Adapter GPIO support"
+	depends on MFD_LJCA
+	select GPIOLIB_IRQCHIP
+	default MFD_LJCA
+	help
+	  Select this option to enable GPIO driver for the INTEL
+	  La Jolla Cove Adapter (LJCA) board.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called gpio-ljca.
+
 config GPIO_LP3943
 	tristate "TI/National Semiconductor LP3943 GPIO expander"
 	depends on MFD_LP3943
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index c048ba003367..eb59524d18c0 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -77,6 +77,7 @@  obj-$(CONFIG_GPIO_IXP4XX)		+= gpio-ixp4xx.o
 obj-$(CONFIG_GPIO_JANZ_TTL)		+= gpio-janz-ttl.o
 obj-$(CONFIG_GPIO_KEMPLD)		+= gpio-kempld.o
 obj-$(CONFIG_GPIO_LATCH)		+= gpio-latch.o
+obj-$(CONFIG_GPIO_LJCA) 		+= gpio-ljca.o
 obj-$(CONFIG_GPIO_LOGICVC)		+= gpio-logicvc.o
 obj-$(CONFIG_GPIO_LOONGSON1)		+= gpio-loongson1.o
 obj-$(CONFIG_GPIO_LOONGSON)		+= gpio-loongson.o
diff --git a/drivers/gpio/gpio-ljca.c b/drivers/gpio/gpio-ljca.c
new file mode 100644
index 000000000000..87863f0230f5
--- /dev/null
+++ b/drivers/gpio/gpio-ljca.c
@@ -0,0 +1,454 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel La Jolla Cove Adapter USB-GPIO driver
+ *
+ * Copyright (c) 2023, Intel Corporation.
+ */
+
+#include <linux/acpi.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/dev_printk.h>
+#include <linux/gpio/driver.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/kref.h>
+#include <linux/mfd/ljca.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+/* GPIO commands */
+#define LJCA_GPIO_CONFIG	1
+#define LJCA_GPIO_READ		2
+#define LJCA_GPIO_WRITE		3
+#define LJCA_GPIO_INT_EVENT	4
+#define LJCA_GPIO_INT_MASK	5
+#define LJCA_GPIO_INT_UNMASK	6
+
+#define LJCA_GPIO_CONF_DISABLE		BIT(0)
+#define LJCA_GPIO_CONF_INPUT		BIT(1)
+#define LJCA_GPIO_CONF_OUTPUT		BIT(2)
+#define LJCA_GPIO_CONF_PULLUP		BIT(3)
+#define LJCA_GPIO_CONF_PULLDOWN		BIT(4)
+#define LJCA_GPIO_CONF_DEFAULT		BIT(5)
+#define LJCA_GPIO_CONF_INTERRUPT	BIT(6)
+#define LJCA_GPIO_INT_TYPE		BIT(7)
+
+#define LJCA_GPIO_CONF_EDGE	FIELD_PREP(LJCA_GPIO_INT_TYPE, 1)
+#define LJCA_GPIO_CONF_LEVEL	FIELD_PREP(LJCA_GPIO_INT_TYPE, 0)
+
+/* Intentional overlap with PULLUP / PULLDOWN */
+#define LJCA_GPIO_CONF_SET	BIT(3)
+#define LJCA_GPIO_CONF_CLR	BIT(4)
+
+struct gpio_op {
+	u8 index;
+	u8 value;
+} __packed;
+
+struct gpio_packet {
+	u8 num;
+	struct gpio_op item[];
+} __packed;
+
+#define LJCA_GPIO_BUF_SIZE 60
+struct ljca_gpio_dev {
+	struct platform_device *pdev;
+	struct gpio_chip gc;
+	struct ljca_gpio_info *gpio_info;
+	DECLARE_BITMAP(unmasked_irqs, LJCA_MAX_GPIO_NUM);
+	DECLARE_BITMAP(enabled_irqs, LJCA_MAX_GPIO_NUM);
+	DECLARE_BITMAP(reenable_irqs, LJCA_MAX_GPIO_NUM);
+	u8 *connect_mode;
+	/* mutex to protect irq bus */
+	struct mutex irq_lock;
+	struct work_struct work;
+	/* lock to protect package transfer to Hardware */
+	struct mutex trans_lock;
+
+	u8 obuf[LJCA_GPIO_BUF_SIZE];
+	u8 ibuf[LJCA_GPIO_BUF_SIZE];
+};
+
+static int gpio_config(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id, u8 config)
+{
+	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
+	int ret;
+
+	mutex_lock(&ljca_gpio->trans_lock);
+	packet->item[0].index = gpio_id;
+	packet->item[0].value = config | ljca_gpio->connect_mode[gpio_id];
+	packet->num = 1;
+
+	ret = ljca_transfer(ljca_gpio->gpio_info->ljca, LJCA_GPIO_CONFIG, packet,
+			    struct_size(packet, item, packet->num), NULL, NULL);
+	mutex_unlock(&ljca_gpio->trans_lock);
+	return ret;
+}
+
+static int ljca_gpio_read(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id)
+{
+	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
+	struct gpio_packet *ack_packet = (struct gpio_packet *)ljca_gpio->ibuf;
+	unsigned int ibuf_len = LJCA_GPIO_BUF_SIZE;
+	int ret;
+
+	mutex_lock(&ljca_gpio->trans_lock);
+	packet->num = 1;
+	packet->item[0].index = gpio_id;
+	ret = ljca_transfer(ljca_gpio->gpio_info->ljca, LJCA_GPIO_READ, packet,
+			    struct_size(packet, item, packet->num), ljca_gpio->ibuf, &ibuf_len);
+	if (ret)
+		goto out_unlock;
+
+	if (!ibuf_len || ack_packet->num != packet->num) {
+		dev_err(&ljca_gpio->pdev->dev, "failed gpio_id:%u %u", gpio_id, ack_packet->num);
+		ret = -EIO;
+	}
+
+out_unlock:
+	mutex_unlock(&ljca_gpio->trans_lock);
+	if (ret)
+		return ret;
+	return ack_packet->item[0].value > 0;
+}
+
+static int ljca_gpio_write(struct ljca_gpio_dev *ljca_gpio, u8 gpio_id,
+			   int value)
+{
+	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
+	int ret;
+
+	mutex_lock(&ljca_gpio->trans_lock);
+	packet->num = 1;
+	packet->item[0].index = gpio_id;
+	packet->item[0].value = value & 1;
+
+	ret = ljca_transfer(ljca_gpio->gpio_info->ljca, LJCA_GPIO_WRITE, packet,
+			    struct_size(packet, item, packet->num), NULL, NULL);
+	mutex_unlock(&ljca_gpio->trans_lock);
+	return ret;
+}
+
+static int ljca_gpio_get_value(struct gpio_chip *chip, unsigned int offset)
+{
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip);
+
+	return ljca_gpio_read(ljca_gpio, offset);
+}
+
+static void ljca_gpio_set_value(struct gpio_chip *chip, unsigned int offset,
+				int val)
+{
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip);
+	int ret;
+
+	ret = ljca_gpio_write(ljca_gpio, offset, val);
+	if (ret)
+		dev_err(chip->parent, "offset:%u val:%d set value failed %d\n", offset, val, ret);
+}
+
+static int ljca_gpio_direction_input(struct gpio_chip *chip,
+				     unsigned int offset)
+{
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip);
+	u8 config = LJCA_GPIO_CONF_INPUT | LJCA_GPIO_CONF_CLR;
+
+	return gpio_config(ljca_gpio, offset, config);
+}
+
+static int ljca_gpio_direction_output(struct gpio_chip *chip,
+				      unsigned int offset, int val)
+{
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip);
+	u8 config = LJCA_GPIO_CONF_OUTPUT | LJCA_GPIO_CONF_CLR;
+	int ret;
+
+	ret = gpio_config(ljca_gpio, offset, config);
+	if (ret)
+		return ret;
+
+	ljca_gpio_set_value(chip, offset, val);
+	return 0;
+}
+
+static int ljca_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
+				unsigned long config)
+{
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip);
+
+	ljca_gpio->connect_mode[offset] = 0;
+	switch (pinconf_to_config_param(config)) {
+	case PIN_CONFIG_BIAS_PULL_UP:
+		ljca_gpio->connect_mode[offset] |= LJCA_GPIO_CONF_PULLUP;
+		break;
+	case PIN_CONFIG_BIAS_PULL_DOWN:
+		ljca_gpio->connect_mode[offset] |= LJCA_GPIO_CONF_PULLDOWN;
+		break;
+	case PIN_CONFIG_DRIVE_PUSH_PULL:
+	case PIN_CONFIG_PERSIST_STATE:
+		break;
+	default:
+		return -ENOTSUPP;
+	}
+
+	return 0;
+}
+
+static int ljca_gpio_init_valid_mask(struct gpio_chip *chip, unsigned long *valid_mask,
+				     unsigned int ngpios)
+{
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip);
+
+	WARN_ON_ONCE(ngpios != ljca_gpio->gpio_info->num);
+	bitmap_copy(valid_mask, ljca_gpio->gpio_info->valid_pin_map, ngpios);
+
+	return 0;
+}
+
+static void ljca_gpio_irq_init_valid_mask(struct gpio_chip *chip, unsigned long *valid_mask,
+					  unsigned int ngpios)
+{
+	ljca_gpio_init_valid_mask(chip, valid_mask, ngpios);
+}
+
+static int ljca_enable_irq(struct ljca_gpio_dev *ljca_gpio, int gpio_id, bool enable)
+{
+	struct gpio_packet *packet = (struct gpio_packet *)ljca_gpio->obuf;
+	int ret;
+
+	mutex_lock(&ljca_gpio->trans_lock);
+	packet->num = 1;
+	packet->item[0].index = gpio_id;
+	packet->item[0].value = 0;
+
+	ret = ljca_transfer(ljca_gpio->gpio_info->ljca,
+			    enable ? LJCA_GPIO_INT_UNMASK : LJCA_GPIO_INT_MASK, packet,
+			    struct_size(packet, item, packet->num), NULL, NULL);
+	mutex_unlock(&ljca_gpio->trans_lock);
+	return ret;
+}
+
+static void ljca_gpio_async(struct work_struct *work)
+{
+	struct ljca_gpio_dev *ljca_gpio = container_of(work, struct ljca_gpio_dev, work);
+	int gpio_id;
+	int unmasked;
+
+	for_each_set_bit(gpio_id, ljca_gpio->reenable_irqs, ljca_gpio->gc.ngpio) {
+		clear_bit(gpio_id, ljca_gpio->reenable_irqs);
+		unmasked = test_bit(gpio_id, ljca_gpio->unmasked_irqs);
+		if (unmasked)
+			ljca_enable_irq(ljca_gpio, gpio_id, true);
+	}
+}
+
+static void ljca_gpio_event_cb(void *context, u8 cmd, const void *evt_data, int len)
+{
+	const struct gpio_packet *packet = evt_data;
+	struct ljca_gpio_dev *ljca_gpio = context;
+	int i;
+	int irq;
+
+	if (cmd != LJCA_GPIO_INT_EVENT)
+		return;
+
+	for (i = 0; i < packet->num; i++) {
+		irq = irq_find_mapping(ljca_gpio->gc.irq.domain, packet->item[i].index);
+		if (!irq) {
+			dev_err(ljca_gpio->gc.parent, "gpio_id %u does not mapped to IRQ yet\n",
+				packet->item[i].index);
+			return;
+		}
+
+		generic_handle_domain_irq(ljca_gpio->gc.irq.domain, irq);
+		set_bit(packet->item[i].index, ljca_gpio->reenable_irqs);
+	}
+
+	schedule_work(&ljca_gpio->work);
+}
+
+static void ljca_irq_unmask(struct irq_data *irqd)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc);
+	int gpio_id = irqd_to_hwirq(irqd);
+
+	gpiochip_enable_irq(gc, gpio_id);
+	set_bit(gpio_id, ljca_gpio->unmasked_irqs);
+}
+
+static void ljca_irq_mask(struct irq_data *irqd)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc);
+	int gpio_id = irqd_to_hwirq(irqd);
+
+	clear_bit(gpio_id, ljca_gpio->unmasked_irqs);
+	gpiochip_disable_irq(gc, gpio_id);
+}
+
+static int ljca_irq_set_type(struct irq_data *irqd, unsigned int type)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc);
+	int gpio_id = irqd_to_hwirq(irqd);
+
+	ljca_gpio->connect_mode[gpio_id] = LJCA_GPIO_CONF_INTERRUPT;
+	switch (type) {
+	case IRQ_TYPE_LEVEL_HIGH:
+		ljca_gpio->connect_mode[gpio_id] |= (LJCA_GPIO_CONF_LEVEL | LJCA_GPIO_CONF_PULLUP);
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		ljca_gpio->connect_mode[gpio_id] |= (LJCA_GPIO_CONF_LEVEL | LJCA_GPIO_CONF_PULLDOWN);
+		break;
+	case IRQ_TYPE_EDGE_BOTH:
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+		ljca_gpio->connect_mode[gpio_id] |= (LJCA_GPIO_CONF_EDGE | LJCA_GPIO_CONF_PULLUP);
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		ljca_gpio->connect_mode[gpio_id] |= (LJCA_GPIO_CONF_EDGE | LJCA_GPIO_CONF_PULLDOWN);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void ljca_irq_bus_lock(struct irq_data *irqd)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc);
+
+	mutex_lock(&ljca_gpio->irq_lock);
+}
+
+static void ljca_irq_bus_unlock(struct irq_data *irqd)
+{
+	struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
+	struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(gc);
+	int gpio_id = irqd_to_hwirq(irqd);
+	int enabled;
+	int unmasked;
+
+	enabled = test_bit(gpio_id, ljca_gpio->enabled_irqs);
+	unmasked = test_bit(gpio_id, ljca_gpio->unmasked_irqs);
+
+	if (enabled != unmasked) {
+		if (unmasked) {
+			gpio_config(ljca_gpio, gpio_id, 0);
+			ljca_enable_irq(ljca_gpio, gpio_id, true);
+			set_bit(gpio_id, ljca_gpio->enabled_irqs);
+		} else {
+			ljca_enable_irq(ljca_gpio, gpio_id, false);
+			clear_bit(gpio_id, ljca_gpio->enabled_irqs);
+		}
+	}
+
+	mutex_unlock(&ljca_gpio->irq_lock);
+}
+
+static const struct irq_chip ljca_gpio_irqchip = {
+	.name = "ljca-irq",
+	.irq_mask = ljca_irq_mask,
+	.irq_unmask = ljca_irq_unmask,
+	.irq_set_type = ljca_irq_set_type,
+	.irq_bus_lock = ljca_irq_bus_lock,
+	.irq_bus_sync_unlock = ljca_irq_bus_unlock,
+	.flags = IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static int ljca_gpio_probe(struct platform_device *pdev)
+{
+	struct ljca_gpio_dev *ljca_gpio;
+	struct gpio_irq_chip *girq;
+	int ret;
+
+	ljca_gpio = devm_kzalloc(&pdev->dev, sizeof(*ljca_gpio), GFP_KERNEL);
+	if (!ljca_gpio)
+		return -ENOMEM;
+
+	ljca_gpio->gpio_info = dev_get_platdata(&pdev->dev);
+	ljca_gpio->connect_mode = devm_kcalloc(&pdev->dev, ljca_gpio->gpio_info->num,
+					       sizeof(*ljca_gpio->connect_mode), GFP_KERNEL);
+	if (!ljca_gpio->connect_mode)
+		return -ENOMEM;
+
+	mutex_init(&ljca_gpio->irq_lock);
+	mutex_init(&ljca_gpio->trans_lock);
+	ljca_gpio->pdev = pdev;
+	ljca_gpio->gc.direction_input = ljca_gpio_direction_input;
+	ljca_gpio->gc.direction_output = ljca_gpio_direction_output;
+	ljca_gpio->gc.get = ljca_gpio_get_value;
+	ljca_gpio->gc.set = ljca_gpio_set_value;
+	ljca_gpio->gc.set_config = ljca_gpio_set_config;
+	ljca_gpio->gc.init_valid_mask = ljca_gpio_init_valid_mask;
+	ljca_gpio->gc.can_sleep = true;
+	ljca_gpio->gc.parent = &pdev->dev;
+
+	ljca_gpio->gc.base = -1;
+	ljca_gpio->gc.ngpio = ljca_gpio->gpio_info->num;
+	ljca_gpio->gc.label = ACPI_COMPANION(&pdev->dev) ?
+			      acpi_dev_name(ACPI_COMPANION(&pdev->dev)) :
+			      dev_name(&pdev->dev);
+	ljca_gpio->gc.owner = THIS_MODULE;
+
+	platform_set_drvdata(pdev, ljca_gpio);
+	ljca_register_event_cb(ljca_gpio->gpio_info->ljca, ljca_gpio_event_cb, ljca_gpio);
+
+	girq = &ljca_gpio->gc.irq;
+	gpio_irq_chip_set_chip(girq, &ljca_gpio_irqchip);
+	girq->parent_handler = NULL;
+	girq->num_parents = 0;
+	girq->parents = NULL;
+	girq->default_type = IRQ_TYPE_NONE;
+	girq->handler = handle_simple_irq;
+	girq->init_valid_mask = ljca_gpio_irq_init_valid_mask;
+
+	INIT_WORK(&ljca_gpio->work, ljca_gpio_async);
+	ret = gpiochip_add_data(&ljca_gpio->gc, ljca_gpio);
+	if (ret) {
+		ljca_unregister_event_cb(ljca_gpio->gpio_info->ljca);
+		mutex_destroy(&ljca_gpio->irq_lock);
+		mutex_destroy(&ljca_gpio->trans_lock);
+	}
+
+	return ret;
+}
+
+static int ljca_gpio_remove(struct platform_device *pdev)
+{
+	struct ljca_gpio_dev *ljca_gpio = platform_get_drvdata(pdev);
+
+	gpiochip_remove(&ljca_gpio->gc);
+	ljca_unregister_event_cb(ljca_gpio->gpio_info->ljca);
+	mutex_destroy(&ljca_gpio->irq_lock);
+	mutex_destroy(&ljca_gpio->trans_lock);
+	return 0;
+}
+
+#define LJCA_GPIO_DRV_NAME "ljca-gpio"
+static const struct platform_device_id ljca_gpio_id[] = {
+	{ LJCA_GPIO_DRV_NAME, 0 },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(platform, ljca_gpio_id);
+
+static struct platform_driver ljca_gpio_driver = {
+	.driver.name = LJCA_GPIO_DRV_NAME,
+	.probe = ljca_gpio_probe,
+	.remove = ljca_gpio_remove,
+};
+module_platform_driver(ljca_gpio_driver);
+
+MODULE_AUTHOR("Ye Xiang <xiang.ye@intel.com>");
+MODULE_AUTHOR("Wang Zhifeng <zhifeng.wang@intel.com>");
+MODULE_AUTHOR("Zhang Lixu <lixu.zhang@intel.com>");
+MODULE_DESCRIPTION("Intel La Jolla Cove Adapter USB-GPIO driver");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(LJCA);