// SPDX-License-Identifier: GPL-2.0-only /* * MAX732x I2C Port Expander with 8/16 I/O * * Copyright (C) 2007 Marvell International Ltd. * Copyright (C) 2008 Jack Ren <[email protected]> * Copyright (C) 2008 Eric Miao <[email protected]> * Copyright (C) 2015 Linus Walleij <[email protected]> * * Derived from drivers/gpio/pca953x.c */ #include <linux/module.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/string.h> #include <linux/gpio/driver.h> #include <linux/interrupt.h> #include <linux/i2c.h> #include <linux/platform_data/max732x.h> /* * Each port of MAX732x (including MAX7319) falls into one of the * following three types: * * - Push Pull Output * - Input * - Open Drain I/O * * designated by 'O', 'I' and 'P' individually according to MAXIM's * datasheets. 'I' and 'P' ports are interrupt capables, some with * a dedicated interrupt mask. * * There are two groups of I/O ports, each group usually includes * up to 8 I/O ports, and is accessed by a specific I2C address: * * - Group A : by I2C address 0b'110xxxx * - Group B : by I2C address 0b'101xxxx * * where 'xxxx' is decided by the connections of pin AD2/AD0. The * address used also affects the initial state of output signals. * * Within each group of ports, there are five known combinations of * I/O ports: 4I4O, 4P4O, 8I, 8P, 8O, see the definitions below for * the detailed organization of these ports. Only Goup A is interrupt * capable. * * GPIO numbers start from 'gpio_base + 0' to 'gpio_base + 8/16', * and GPIOs from GROUP_A are numbered before those from GROUP_B * (if there are two groups). * * NOTE: MAX7328/MAX7329 are drop-in replacements for PCF8574/a, so * they are not supported by this driver. */ #define PORT_NONE … #define PORT_OUTPUT … #define PORT_INPUT … #define PORT_OPENDRAIN … #define IO_4I4O … #define IO_4P4O … #define IO_8I … #define IO_8P … #define IO_8O … #define GROUP_A(x) … #define GROUP_B(x) … #define INT_NONE … #define INT_NO_MASK … #define INT_INDEP_MASK … #define INT_MERGED_MASK … #define INT_CAPS(x) … enum { … }; static uint64_t max732x_features[] = …; static const struct i2c_device_id max732x_id[] = …; MODULE_DEVICE_TABLE(i2c, max732x_id); static const struct of_device_id max732x_of_table[] = …; MODULE_DEVICE_TABLE(of, max732x_of_table); struct max732x_chip { … }; static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val) { … } static int max732x_readb(struct max732x_chip *chip, int group_a, uint8_t *val) { … } static inline int is_group_a(struct max732x_chip *chip, unsigned off) { … } static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off) { … } static void max732x_gpio_set_mask(struct gpio_chip *gc, unsigned off, int mask, int val) { … } static void max732x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val) { … } static void max732x_gpio_set_multiple(struct gpio_chip *gc, unsigned long *mask, unsigned long *bits) { … } static int max732x_gpio_direction_input(struct gpio_chip *gc, unsigned off) { … } static int max732x_gpio_direction_output(struct gpio_chip *gc, unsigned off, int val) { … } #ifdef CONFIG_GPIO_MAX732X_IRQ static int max732x_writew(struct max732x_chip *chip, uint16_t val) { … } static int max732x_readw(struct max732x_chip *chip, uint16_t *val) { … } static void max732x_irq_update_mask(struct max732x_chip *chip) { … } static void max732x_irq_mask(struct irq_data *d) { … } static void max732x_irq_unmask(struct irq_data *d) { … } static void max732x_irq_bus_lock(struct irq_data *d) { … } static void max732x_irq_bus_sync_unlock(struct irq_data *d) { … } static int max732x_irq_set_type(struct irq_data *d, unsigned int type) { … } static int max732x_irq_set_wake(struct irq_data *data, unsigned int on) { … } static const struct irq_chip max732x_irq_chip = …; static uint8_t max732x_irq_pending(struct max732x_chip *chip) { … } static irqreturn_t max732x_irq_handler(int irq, void *devid) { … } static int max732x_irq_setup(struct max732x_chip *chip, const struct i2c_device_id *id) { … } #else /* CONFIG_GPIO_MAX732X_IRQ */ static int max732x_irq_setup(struct max732x_chip *chip, const struct i2c_device_id *id) { struct i2c_client *client = chip->client; int has_irq = max732x_features[id->driver_data] >> 32; if (client->irq && has_irq != INT_NONE) dev_warn(&client->dev, "interrupt support not compiled in\n"); return 0; } #endif static int max732x_setup_gpio(struct max732x_chip *chip, const struct i2c_device_id *id, unsigned gpio_start) { … } static struct max732x_platform_data *of_gpio_max732x(struct device *dev) { … } static int max732x_probe(struct i2c_client *client) { … } static struct i2c_driver max732x_driver = …; static int __init max732x_init(void) { … } /* register after i2c postcore initcall and before * subsys initcalls that may rely on these GPIOs */ subsys_initcall(max732x_init); static void __exit max732x_exit(void) { … } module_exit(max732x_exit); MODULE_AUTHOR(…) …; MODULE_DESCRIPTION(…) …; MODULE_LICENSE(…) …;
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