diff options
author | Ye Xiang <xiang.ye@intel.com> | 2023-02-25 22:01:15 +0800 |
---|---|---|
committer | Lee Jones <lee@kernel.org> | 2023-04-26 11:40:29 +0100 |
commit | c5a4b6fd31e8cbc749f7ac9ff6c3a6118f3e5011 (patch) | |
tree | 5af63b5807ff513241e912b26ab31dce23a24b54 | |
parent | b8fd17d9505e18001d10ceaa350c118a82b467bb (diff) | |
download | linux-next-c5a4b6fd31e8cbc749f7ac9ff6c3a6118f3e5011.tar.gz |
gpio: Add support for Intel LJCA USB GPIO driver
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>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230225140118.2037220-3-xiang.ye@intel.com
-rw-r--r-- | drivers/gpio/Kconfig | 12 | ||||
-rw-r--r-- | drivers/gpio/Makefile | 1 | ||||
-rw-r--r-- | drivers/gpio/gpio-ljca.c | 454 |
3 files changed, 467 insertions, 0 deletions
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); |