> -----Original Message-----
> From: Ye, Xiang <xiang.ye@xxxxxxxxx>
> Sent: Friday, May 12, 2023 1:59 AM
>
> 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@xxxxxxxxx>
> ---
> drivers/gpio/Kconfig | 12 +
> drivers/gpio/Makefile | 1 +
> drivers/gpio/gpio-ljca.c | 479 +++++++++++++++++++++++++++++++++++++++
> 3 files changed, 492 insertions(+)
> create mode 100644 drivers/gpio/gpio-ljca.c
>
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index
> 13be729710f2..bbf00e157dcd 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -1658,6 +1658,18 @@ config GPIO_VIPERBOARD
> River Tech's viperboard.h for detailed meaning
> of the module parameters.
>
> +config GPIO_LJCA
> + tristate "INTEL La Jolla Cove Adapter GPIO support"
> + depends on USB_LJCA
> + select GPIOLIB_IRQCHIP
> + default USB_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.
> +
> endmenu
>
> menu "Virtual GPIO drivers"
> 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..81835a21e8c0
> --- /dev/null
> +++ b/drivers/gpio/gpio-ljca.c
> @@ -0,0 +1,479 @@
> +// 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/auxiliary_bus.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/module.h>
> +#include <linux/slab.h>
> +#include <linux/types.h>
> +#include <linux/usb/ljca.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 ljca *ljca;
> + 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);
> + DECLARE_BITMAP(output_enabled, 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->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->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->ljca->auxdev.dev,
> + "read package error, gpio_id:%u num:%u
> ibuf_len:%d\n", gpio_id,
> + ack_packet->num, ibuf_len);
> + 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->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, "set value failed offset:%u val:%d
> ret:%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;
> + int ret;
> +
> + ret = gpio_config(ljca_gpio, offset, config);
> + if (ret)
> + return ret;
> +
> + clear_bit(offset, ljca_gpio->output_enabled);
> +
> + return 0;
> +}
> +
> +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);
> + set_bit(offset, ljca_gpio->output_enabled);
> +
> + return 0;
> +}
> +
> +static int ljca_gpio_get_direction(struct gpio_chip *chip, unsigned int
> +offset) {
> + struct ljca_gpio_dev *ljca_gpio = gpiochip_get_data(chip);
> +
> + if (test_bit(offset, ljca_gpio->output_enabled))
> + return GPIO_LINE_DIRECTION_OUT;
> +
> + return GPIO_LINE_DIRECTION_IN;
> +}
> +
> +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->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 auxiliary_device *auxdev,
> + const struct auxiliary_device_id *aux_dev_id) {
> + struct ljca *ljca = auxiliary_dev_to_ljca(auxdev);
> + struct ljca_gpio_dev *ljca_gpio;
> + struct gpio_irq_chip *girq;
> + int ret;
> +
> + ljca_gpio = devm_kzalloc(&auxdev->dev, sizeof(*ljca_gpio),
> GFP_KERNEL);
> + if (!ljca_gpio)
> + return -ENOMEM;
> +
> + ljca_gpio->ljca = ljca;
> + ljca_gpio->gpio_info = dev_get_platdata(&auxdev->dev);
> + ljca_gpio->connect_mode = devm_kcalloc(&auxdev->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->gc.direction_input = ljca_gpio_direction_input;
> + ljca_gpio->gc.direction_output = ljca_gpio_direction_output;
> + ljca_gpio->gc.get_direction = ljca_gpio_get_direction;
> + 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 = &auxdev->dev;
> +
> + ljca_gpio->gc.base = -1;
> + ljca_gpio->gc.ngpio = ljca_gpio->gpio_info->num;
> + ljca_gpio->gc.label = ACPI_COMPANION(&auxdev->dev) ?
> + acpi_dev_name(ACPI_COMPANION(&auxdev->dev)) :
> + dev_name(&auxdev->dev);
> + ljca_gpio->gc.owner = THIS_MODULE;
> +
> + auxiliary_set_drvdata(auxdev, ljca_gpio);
> + ljca_register_event_cb(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);
> + mutex_destroy(&ljca_gpio->irq_lock);
> + mutex_destroy(&ljca_gpio->trans_lock);
> + }
> +
> + return ret;
> +}
> +
> +static void ljca_gpio_remove(struct auxiliary_device *auxdev) {
> + struct ljca_gpio_dev *ljca_gpio = auxiliary_get_drvdata(auxdev);
> +
> + gpiochip_remove(&ljca_gpio->gc);
> + ljca_unregister_event_cb(ljca_gpio->ljca);
> + cancel_work_sync(&ljca_gpio->work);
> + mutex_destroy(&ljca_gpio->irq_lock);
> + mutex_destroy(&ljca_gpio->trans_lock);
> +}
> +
> +#define LJCA_GPIO_DRV_NAME "ljca.ljca-gpio"
The wrong name causes the probe match failed. The name should be
"usb_ljca.ljca-gpio", the same as spi and i2c.
BR,
Wentong
> +static const struct auxiliary_device_id ljca_gpio_id_table[] = {
> + { LJCA_GPIO_DRV_NAME, 0 },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(auxiliary, ljca_gpio_id_table);
> +
> +static struct auxiliary_driver ljca_gpio_driver = {
> + .probe = ljca_gpio_probe,
> + .remove = ljca_gpio_remove,
> + .id_table = ljca_gpio_id_table,
> +};
> +module_auxiliary_driver(ljca_gpio_driver);
> +
> +MODULE_AUTHOR("Ye Xiang <xiang.ye@xxxxxxxxx>");
> MODULE_AUTHOR("Wang
> +Zhifeng <zhifeng.wang@xxxxxxxxx>"); MODULE_AUTHOR("Zhang Lixu
> +<lixu.zhang@xxxxxxxxx>"); MODULE_DESCRIPTION("Intel La Jolla Cove
> +Adapter USB-GPIO driver"); MODULE_LICENSE("GPL");
> +MODULE_IMPORT_NS(LJCA);
> --
> 2.34.1
