| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * GPIO Greybus driver. |
| * |
| * Copyright 2014 Google Inc. |
| * Copyright 2014 Linaro Ltd. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/irq.h> |
| #include <linux/irqdomain.h> |
| #include <linux/gpio/driver.h> |
| #include <linux/mutex.h> |
| |
| #include "greybus.h" |
| #include "gbphy.h" |
| |
| struct gb_gpio_line { |
| /* The following has to be an array of line_max entries */ |
| /* --> make them just a flags field */ |
| u8 active: 1, |
| direction: 1, /* 0 = output, 1 = input */ |
| value: 1; /* 0 = low, 1 = high */ |
| u16 debounce_usec; |
| |
| u8 irq_type; |
| bool irq_type_pending; |
| bool masked; |
| bool masked_pending; |
| }; |
| |
| struct gb_gpio_controller { |
| struct gbphy_device *gbphy_dev; |
| struct gb_connection *connection; |
| u8 line_max; /* max line number */ |
| struct gb_gpio_line *lines; |
| |
| struct gpio_chip chip; |
| struct irq_chip irqc; |
| struct mutex irq_lock; |
| }; |
| #define gpio_chip_to_gb_gpio_controller(chip) \ |
| container_of(chip, struct gb_gpio_controller, chip) |
| #define irq_data_to_gpio_chip(d) (d->domain->host_data) |
| |
| static int gb_gpio_line_count_operation(struct gb_gpio_controller *ggc) |
| { |
| struct gb_gpio_line_count_response response; |
| int ret; |
| |
| ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_LINE_COUNT, |
| NULL, 0, &response, sizeof(response)); |
| if (!ret) |
| ggc->line_max = response.count; |
| return ret; |
| } |
| |
| static int gb_gpio_activate_operation(struct gb_gpio_controller *ggc, u8 which) |
| { |
| struct gb_gpio_activate_request request; |
| struct gbphy_device *gbphy_dev = ggc->gbphy_dev; |
| int ret; |
| |
| ret = gbphy_runtime_get_sync(gbphy_dev); |
| if (ret) |
| return ret; |
| |
| request.which = which; |
| ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_ACTIVATE, |
| &request, sizeof(request), NULL, 0); |
| if (ret) { |
| gbphy_runtime_put_autosuspend(gbphy_dev); |
| return ret; |
| } |
| |
| ggc->lines[which].active = true; |
| |
| return 0; |
| } |
| |
| static void gb_gpio_deactivate_operation(struct gb_gpio_controller *ggc, |
| u8 which) |
| { |
| struct gbphy_device *gbphy_dev = ggc->gbphy_dev; |
| struct device *dev = &gbphy_dev->dev; |
| struct gb_gpio_deactivate_request request; |
| int ret; |
| |
| request.which = which; |
| ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_DEACTIVATE, |
| &request, sizeof(request), NULL, 0); |
| if (ret) { |
| dev_err(dev, "failed to deactivate gpio %u\n", which); |
| goto out_pm_put; |
| } |
| |
| ggc->lines[which].active = false; |
| |
| out_pm_put: |
| gbphy_runtime_put_autosuspend(gbphy_dev); |
| } |
| |
| static int gb_gpio_get_direction_operation(struct gb_gpio_controller *ggc, |
| u8 which) |
| { |
| struct device *dev = &ggc->gbphy_dev->dev; |
| struct gb_gpio_get_direction_request request; |
| struct gb_gpio_get_direction_response response; |
| int ret; |
| u8 direction; |
| |
| request.which = which; |
| ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_GET_DIRECTION, |
| &request, sizeof(request), |
| &response, sizeof(response)); |
| if (ret) |
| return ret; |
| |
| direction = response.direction; |
| if (direction && direction != 1) { |
| dev_warn(dev, "gpio %u direction was %u (should be 0 or 1)\n", |
| which, direction); |
| } |
| ggc->lines[which].direction = direction ? 1 : 0; |
| return 0; |
| } |
| |
| static int gb_gpio_direction_in_operation(struct gb_gpio_controller *ggc, |
| u8 which) |
| { |
| struct gb_gpio_direction_in_request request; |
| int ret; |
| |
| request.which = which; |
| ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_DIRECTION_IN, |
| &request, sizeof(request), NULL, 0); |
| if (!ret) |
| ggc->lines[which].direction = 1; |
| return ret; |
| } |
| |
| static int gb_gpio_direction_out_operation(struct gb_gpio_controller *ggc, |
| u8 which, bool value_high) |
| { |
| struct gb_gpio_direction_out_request request; |
| int ret; |
| |
| request.which = which; |
| request.value = value_high ? 1 : 0; |
| ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_DIRECTION_OUT, |
| &request, sizeof(request), NULL, 0); |
| if (!ret) |
| ggc->lines[which].direction = 0; |
| return ret; |
| } |
| |
| static int gb_gpio_get_value_operation(struct gb_gpio_controller *ggc, |
| u8 which) |
| { |
| struct device *dev = &ggc->gbphy_dev->dev; |
| struct gb_gpio_get_value_request request; |
| struct gb_gpio_get_value_response response; |
| int ret; |
| u8 value; |
| |
| request.which = which; |
| ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_GET_VALUE, |
| &request, sizeof(request), |
| &response, sizeof(response)); |
| if (ret) { |
| dev_err(dev, "failed to get value of gpio %u\n", which); |
| return ret; |
| } |
| |
| value = response.value; |
| if (value && value != 1) { |
| dev_warn(dev, "gpio %u value was %u (should be 0 or 1)\n", |
| which, value); |
| } |
| ggc->lines[which].value = value ? 1 : 0; |
| return 0; |
| } |
| |
| static void gb_gpio_set_value_operation(struct gb_gpio_controller *ggc, |
| u8 which, bool value_high) |
| { |
| struct device *dev = &ggc->gbphy_dev->dev; |
| struct gb_gpio_set_value_request request; |
| int ret; |
| |
| if (ggc->lines[which].direction == 1) { |
| dev_warn(dev, "refusing to set value of input gpio %u\n", |
| which); |
| return; |
| } |
| |
| request.which = which; |
| request.value = value_high ? 1 : 0; |
| ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_SET_VALUE, |
| &request, sizeof(request), NULL, 0); |
| if (ret) { |
| dev_err(dev, "failed to set value of gpio %u\n", which); |
| return; |
| } |
| |
| ggc->lines[which].value = request.value; |
| } |
| |
| static int gb_gpio_set_debounce_operation(struct gb_gpio_controller *ggc, |
| u8 which, u16 debounce_usec) |
| { |
| struct gb_gpio_set_debounce_request request; |
| int ret; |
| |
| request.which = which; |
| request.usec = cpu_to_le16(debounce_usec); |
| ret = gb_operation_sync(ggc->connection, GB_GPIO_TYPE_SET_DEBOUNCE, |
| &request, sizeof(request), NULL, 0); |
| if (!ret) |
| ggc->lines[which].debounce_usec = debounce_usec; |
| return ret; |
| } |
| |
| static void _gb_gpio_irq_mask(struct gb_gpio_controller *ggc, u8 hwirq) |
| { |
| struct device *dev = &ggc->gbphy_dev->dev; |
| struct gb_gpio_irq_mask_request request; |
| int ret; |
| |
| request.which = hwirq; |
| ret = gb_operation_sync(ggc->connection, |
| GB_GPIO_TYPE_IRQ_MASK, |
| &request, sizeof(request), NULL, 0); |
| if (ret) |
| dev_err(dev, "failed to mask irq: %d\n", ret); |
| } |
| |
| static void _gb_gpio_irq_unmask(struct gb_gpio_controller *ggc, u8 hwirq) |
| { |
| struct device *dev = &ggc->gbphy_dev->dev; |
| struct gb_gpio_irq_unmask_request request; |
| int ret; |
| |
| request.which = hwirq; |
| ret = gb_operation_sync(ggc->connection, |
| GB_GPIO_TYPE_IRQ_UNMASK, |
| &request, sizeof(request), NULL, 0); |
| if (ret) |
| dev_err(dev, "failed to unmask irq: %d\n", ret); |
| } |
| |
| static void _gb_gpio_irq_set_type(struct gb_gpio_controller *ggc, |
| u8 hwirq, u8 type) |
| { |
| struct device *dev = &ggc->gbphy_dev->dev; |
| struct gb_gpio_irq_type_request request; |
| int ret; |
| |
| request.which = hwirq; |
| request.type = type; |
| |
| ret = gb_operation_sync(ggc->connection, |
| GB_GPIO_TYPE_IRQ_TYPE, |
| &request, sizeof(request), NULL, 0); |
| if (ret) |
| dev_err(dev, "failed to set irq type: %d\n", ret); |
| } |
| |
| static void gb_gpio_irq_mask(struct irq_data *d) |
| { |
| struct gpio_chip *chip = irq_data_to_gpio_chip(d); |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| struct gb_gpio_line *line = &ggc->lines[d->hwirq]; |
| |
| line->masked = true; |
| line->masked_pending = true; |
| } |
| |
| static void gb_gpio_irq_unmask(struct irq_data *d) |
| { |
| struct gpio_chip *chip = irq_data_to_gpio_chip(d); |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| struct gb_gpio_line *line = &ggc->lines[d->hwirq]; |
| |
| line->masked = false; |
| line->masked_pending = true; |
| } |
| |
| static int gb_gpio_irq_set_type(struct irq_data *d, unsigned int type) |
| { |
| struct gpio_chip *chip = irq_data_to_gpio_chip(d); |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| struct gb_gpio_line *line = &ggc->lines[d->hwirq]; |
| struct device *dev = &ggc->gbphy_dev->dev; |
| u8 irq_type; |
| |
| switch (type) { |
| case IRQ_TYPE_NONE: |
| irq_type = GB_GPIO_IRQ_TYPE_NONE; |
| break; |
| case IRQ_TYPE_EDGE_RISING: |
| irq_type = GB_GPIO_IRQ_TYPE_EDGE_RISING; |
| break; |
| case IRQ_TYPE_EDGE_FALLING: |
| irq_type = GB_GPIO_IRQ_TYPE_EDGE_FALLING; |
| break; |
| case IRQ_TYPE_EDGE_BOTH: |
| irq_type = GB_GPIO_IRQ_TYPE_EDGE_BOTH; |
| break; |
| case IRQ_TYPE_LEVEL_LOW: |
| irq_type = GB_GPIO_IRQ_TYPE_LEVEL_LOW; |
| break; |
| case IRQ_TYPE_LEVEL_HIGH: |
| irq_type = GB_GPIO_IRQ_TYPE_LEVEL_HIGH; |
| break; |
| default: |
| dev_err(dev, "unsupported irq type: %u\n", type); |
| return -EINVAL; |
| } |
| |
| line->irq_type = irq_type; |
| line->irq_type_pending = true; |
| |
| return 0; |
| } |
| |
| static void gb_gpio_irq_bus_lock(struct irq_data *d) |
| { |
| struct gpio_chip *chip = irq_data_to_gpio_chip(d); |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| |
| mutex_lock(&ggc->irq_lock); |
| } |
| |
| static void gb_gpio_irq_bus_sync_unlock(struct irq_data *d) |
| { |
| struct gpio_chip *chip = irq_data_to_gpio_chip(d); |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| struct gb_gpio_line *line = &ggc->lines[d->hwirq]; |
| |
| if (line->irq_type_pending) { |
| _gb_gpio_irq_set_type(ggc, d->hwirq, line->irq_type); |
| line->irq_type_pending = false; |
| } |
| |
| if (line->masked_pending) { |
| if (line->masked) |
| _gb_gpio_irq_mask(ggc, d->hwirq); |
| else |
| _gb_gpio_irq_unmask(ggc, d->hwirq); |
| line->masked_pending = false; |
| } |
| |
| mutex_unlock(&ggc->irq_lock); |
| } |
| |
| static int gb_gpio_request_handler(struct gb_operation *op) |
| { |
| struct gb_connection *connection = op->connection; |
| struct gb_gpio_controller *ggc = gb_connection_get_data(connection); |
| struct device *dev = &ggc->gbphy_dev->dev; |
| struct gb_message *request; |
| struct gb_gpio_irq_event_request *event; |
| u8 type = op->type; |
| int irq; |
| struct irq_desc *desc; |
| |
| if (type != GB_GPIO_TYPE_IRQ_EVENT) { |
| dev_err(dev, "unsupported unsolicited request: %u\n", type); |
| return -EINVAL; |
| } |
| |
| request = op->request; |
| |
| if (request->payload_size < sizeof(*event)) { |
| dev_err(dev, "short event received (%zu < %zu)\n", |
| request->payload_size, sizeof(*event)); |
| return -EINVAL; |
| } |
| |
| event = request->payload; |
| if (event->which > ggc->line_max) { |
| dev_err(dev, "invalid hw irq: %d\n", event->which); |
| return -EINVAL; |
| } |
| |
| irq = irq_find_mapping(ggc->chip.irq.domain, event->which); |
| if (!irq) { |
| dev_err(dev, "failed to find IRQ\n"); |
| return -EINVAL; |
| } |
| desc = irq_to_desc(irq); |
| if (!desc) { |
| dev_err(dev, "failed to look up irq\n"); |
| return -EINVAL; |
| } |
| |
| local_irq_disable(); |
| generic_handle_irq_desc(desc); |
| local_irq_enable(); |
| |
| return 0; |
| } |
| |
| static int gb_gpio_request(struct gpio_chip *chip, unsigned int offset) |
| { |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| |
| return gb_gpio_activate_operation(ggc, (u8)offset); |
| } |
| |
| static void gb_gpio_free(struct gpio_chip *chip, unsigned int offset) |
| { |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| |
| gb_gpio_deactivate_operation(ggc, (u8)offset); |
| } |
| |
| static int gb_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) |
| { |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| u8 which; |
| int ret; |
| |
| which = (u8)offset; |
| ret = gb_gpio_get_direction_operation(ggc, which); |
| if (ret) |
| return ret; |
| |
| return ggc->lines[which].direction ? 1 : 0; |
| } |
| |
| static int gb_gpio_direction_input(struct gpio_chip *chip, unsigned int offset) |
| { |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| |
| return gb_gpio_direction_in_operation(ggc, (u8)offset); |
| } |
| |
| static int gb_gpio_direction_output(struct gpio_chip *chip, unsigned int offset, |
| int value) |
| { |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| |
| return gb_gpio_direction_out_operation(ggc, (u8)offset, !!value); |
| } |
| |
| static int gb_gpio_get(struct gpio_chip *chip, unsigned int offset) |
| { |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| u8 which; |
| int ret; |
| |
| which = (u8)offset; |
| ret = gb_gpio_get_value_operation(ggc, which); |
| if (ret) |
| return ret; |
| |
| return ggc->lines[which].value; |
| } |
| |
| static void gb_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) |
| { |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| |
| gb_gpio_set_value_operation(ggc, (u8)offset, !!value); |
| } |
| |
| static int gb_gpio_set_config(struct gpio_chip *chip, unsigned int offset, |
| unsigned long config) |
| { |
| struct gb_gpio_controller *ggc = gpio_chip_to_gb_gpio_controller(chip); |
| u32 debounce; |
| |
| if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE) |
| return -ENOTSUPP; |
| |
| debounce = pinconf_to_config_argument(config); |
| if (debounce > U16_MAX) |
| return -EINVAL; |
| |
| return gb_gpio_set_debounce_operation(ggc, (u8)offset, (u16)debounce); |
| } |
| |
| static int gb_gpio_controller_setup(struct gb_gpio_controller *ggc) |
| { |
| int ret; |
| |
| /* Now find out how many lines there are */ |
| ret = gb_gpio_line_count_operation(ggc); |
| if (ret) |
| return ret; |
| |
| ggc->lines = kcalloc(ggc->line_max + 1, sizeof(*ggc->lines), |
| GFP_KERNEL); |
| if (!ggc->lines) |
| return -ENOMEM; |
| |
| return ret; |
| } |
| |
| static int gb_gpio_probe(struct gbphy_device *gbphy_dev, |
| const struct gbphy_device_id *id) |
| { |
| struct gb_connection *connection; |
| struct gb_gpio_controller *ggc; |
| struct gpio_chip *gpio; |
| struct irq_chip *irqc; |
| int ret; |
| |
| ggc = kzalloc(sizeof(*ggc), GFP_KERNEL); |
| if (!ggc) |
| return -ENOMEM; |
| |
| connection = |
| gb_connection_create(gbphy_dev->bundle, |
| le16_to_cpu(gbphy_dev->cport_desc->id), |
| gb_gpio_request_handler); |
| if (IS_ERR(connection)) { |
| ret = PTR_ERR(connection); |
| goto exit_ggc_free; |
| } |
| |
| ggc->connection = connection; |
| gb_connection_set_data(connection, ggc); |
| ggc->gbphy_dev = gbphy_dev; |
| gb_gbphy_set_data(gbphy_dev, ggc); |
| |
| ret = gb_connection_enable_tx(connection); |
| if (ret) |
| goto exit_connection_destroy; |
| |
| ret = gb_gpio_controller_setup(ggc); |
| if (ret) |
| goto exit_connection_disable; |
| |
| irqc = &ggc->irqc; |
| irqc->irq_mask = gb_gpio_irq_mask; |
| irqc->irq_unmask = gb_gpio_irq_unmask; |
| irqc->irq_set_type = gb_gpio_irq_set_type; |
| irqc->irq_bus_lock = gb_gpio_irq_bus_lock; |
| irqc->irq_bus_sync_unlock = gb_gpio_irq_bus_sync_unlock; |
| irqc->name = "greybus_gpio"; |
| |
| mutex_init(&ggc->irq_lock); |
| |
| gpio = &ggc->chip; |
| |
| gpio->label = "greybus_gpio"; |
| gpio->parent = &gbphy_dev->dev; |
| gpio->owner = THIS_MODULE; |
| |
| gpio->request = gb_gpio_request; |
| gpio->free = gb_gpio_free; |
| gpio->get_direction = gb_gpio_get_direction; |
| gpio->direction_input = gb_gpio_direction_input; |
| gpio->direction_output = gb_gpio_direction_output; |
| gpio->get = gb_gpio_get; |
| gpio->set = gb_gpio_set; |
| gpio->set_config = gb_gpio_set_config; |
| gpio->base = -1; /* Allocate base dynamically */ |
| gpio->ngpio = ggc->line_max + 1; |
| gpio->can_sleep = true; |
| |
| ret = gb_connection_enable(connection); |
| if (ret) |
| goto exit_line_free; |
| |
| ret = gpiochip_add(gpio); |
| if (ret) { |
| dev_err(&gbphy_dev->dev, "failed to add gpio chip: %d\n", ret); |
| goto exit_line_free; |
| } |
| |
| ret = gpiochip_irqchip_add(gpio, irqc, 0, handle_level_irq, |
| IRQ_TYPE_NONE); |
| if (ret) { |
| dev_err(&gbphy_dev->dev, "failed to add irq chip: %d\n", ret); |
| goto exit_gpiochip_remove; |
| } |
| |
| gbphy_runtime_put_autosuspend(gbphy_dev); |
| return 0; |
| |
| exit_gpiochip_remove: |
| gpiochip_remove(gpio); |
| exit_line_free: |
| kfree(ggc->lines); |
| exit_connection_disable: |
| gb_connection_disable(connection); |
| exit_connection_destroy: |
| gb_connection_destroy(connection); |
| exit_ggc_free: |
| kfree(ggc); |
| return ret; |
| } |
| |
| static void gb_gpio_remove(struct gbphy_device *gbphy_dev) |
| { |
| struct gb_gpio_controller *ggc = gb_gbphy_get_data(gbphy_dev); |
| struct gb_connection *connection = ggc->connection; |
| int ret; |
| |
| ret = gbphy_runtime_get_sync(gbphy_dev); |
| if (ret) |
| gbphy_runtime_get_noresume(gbphy_dev); |
| |
| gb_connection_disable_rx(connection); |
| gpiochip_remove(&ggc->chip); |
| gb_connection_disable(connection); |
| gb_connection_destroy(connection); |
| kfree(ggc->lines); |
| kfree(ggc); |
| } |
| |
| static const struct gbphy_device_id gb_gpio_id_table[] = { |
| { GBPHY_PROTOCOL(GREYBUS_PROTOCOL_GPIO) }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(gbphy, gb_gpio_id_table); |
| |
| static struct gbphy_driver gpio_driver = { |
| .name = "gpio", |
| .probe = gb_gpio_probe, |
| .remove = gb_gpio_remove, |
| .id_table = gb_gpio_id_table, |
| }; |
| |
| module_gbphy_driver(gpio_driver); |
| MODULE_LICENSE("GPL v2"); |