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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpio/gpio-max732x.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpio/gpio-max732x.c')
-rw-r--r-- | drivers/gpio/gpio-max732x.c | 731 |
1 files changed, 731 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c new file mode 100644 index 000000000..da6972117 --- /dev/null +++ b/drivers/gpio/gpio-max732x.c @@ -0,0 +1,731 @@ +// 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 <jack.ren@marvell.com> + * Copyright (C) 2008 Eric Miao <eric.miao@marvell.com> + * Copyright (C) 2015 Linus Walleij <linus.walleij@linaro.org> + * + * 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> +#include <linux/of.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 0x0 /* '/' No Port */ +#define PORT_OUTPUT 0x1 /* 'O' Push-Pull, Output Only */ +#define PORT_INPUT 0x2 /* 'I' Input Only */ +#define PORT_OPENDRAIN 0x3 /* 'P' Open-Drain, I/O */ + +#define IO_4I4O 0x5AA5 /* O7 O6 I5 I4 I3 I2 O1 O0 */ +#define IO_4P4O 0x5FF5 /* O7 O6 P5 P4 P3 P2 O1 O0 */ +#define IO_8I 0xAAAA /* I7 I6 I5 I4 I3 I2 I1 I0 */ +#define IO_8P 0xFFFF /* P7 P6 P5 P4 P3 P2 P1 P0 */ +#define IO_8O 0x5555 /* O7 O6 O5 O4 O3 O2 O1 O0 */ + +#define GROUP_A(x) ((x) & 0xffff) /* I2C Addr: 0b'110xxxx */ +#define GROUP_B(x) ((x) << 16) /* I2C Addr: 0b'101xxxx */ + +#define INT_NONE 0x0 /* No interrupt capability */ +#define INT_NO_MASK 0x1 /* Has interrupts, no mask */ +#define INT_INDEP_MASK 0x2 /* Has interrupts, independent mask */ +#define INT_MERGED_MASK 0x3 /* Has interrupts, merged mask */ + +#define INT_CAPS(x) (((uint64_t)(x)) << 32) + +enum { + MAX7319, + MAX7320, + MAX7321, + MAX7322, + MAX7323, + MAX7324, + MAX7325, + MAX7326, + MAX7327, +}; + +static uint64_t max732x_features[] = { + [MAX7319] = GROUP_A(IO_8I) | INT_CAPS(INT_MERGED_MASK), + [MAX7320] = GROUP_B(IO_8O), + [MAX7321] = GROUP_A(IO_8P) | INT_CAPS(INT_NO_MASK), + [MAX7322] = GROUP_A(IO_4I4O) | INT_CAPS(INT_MERGED_MASK), + [MAX7323] = GROUP_A(IO_4P4O) | INT_CAPS(INT_INDEP_MASK), + [MAX7324] = GROUP_A(IO_8I) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK), + [MAX7325] = GROUP_A(IO_8P) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK), + [MAX7326] = GROUP_A(IO_4I4O) | GROUP_B(IO_8O) | INT_CAPS(INT_MERGED_MASK), + [MAX7327] = GROUP_A(IO_4P4O) | GROUP_B(IO_8O) | INT_CAPS(INT_NO_MASK), +}; + +static const struct i2c_device_id max732x_id[] = { + { "max7319", MAX7319 }, + { "max7320", MAX7320 }, + { "max7321", MAX7321 }, + { "max7322", MAX7322 }, + { "max7323", MAX7323 }, + { "max7324", MAX7324 }, + { "max7325", MAX7325 }, + { "max7326", MAX7326 }, + { "max7327", MAX7327 }, + { }, +}; +MODULE_DEVICE_TABLE(i2c, max732x_id); + +#ifdef CONFIG_OF +static const struct of_device_id max732x_of_table[] = { + { .compatible = "maxim,max7319" }, + { .compatible = "maxim,max7320" }, + { .compatible = "maxim,max7321" }, + { .compatible = "maxim,max7322" }, + { .compatible = "maxim,max7323" }, + { .compatible = "maxim,max7324" }, + { .compatible = "maxim,max7325" }, + { .compatible = "maxim,max7326" }, + { .compatible = "maxim,max7327" }, + { } +}; +MODULE_DEVICE_TABLE(of, max732x_of_table); +#endif + +struct max732x_chip { + struct gpio_chip gpio_chip; + + struct i2c_client *client; /* "main" client */ + struct i2c_client *client_dummy; + struct i2c_client *client_group_a; + struct i2c_client *client_group_b; + + unsigned int mask_group_a; + unsigned int dir_input; + unsigned int dir_output; + + struct mutex lock; + uint8_t reg_out[2]; + +#ifdef CONFIG_GPIO_MAX732X_IRQ + struct mutex irq_lock; + uint8_t irq_mask; + uint8_t irq_mask_cur; + uint8_t irq_trig_raise; + uint8_t irq_trig_fall; + uint8_t irq_features; +#endif +}; + +static int max732x_writeb(struct max732x_chip *chip, int group_a, uint8_t val) +{ + struct i2c_client *client; + int ret; + + client = group_a ? chip->client_group_a : chip->client_group_b; + ret = i2c_smbus_write_byte(client, val); + if (ret < 0) { + dev_err(&client->dev, "failed writing\n"); + return ret; + } + + return 0; +} + +static int max732x_readb(struct max732x_chip *chip, int group_a, uint8_t *val) +{ + struct i2c_client *client; + int ret; + + client = group_a ? chip->client_group_a : chip->client_group_b; + ret = i2c_smbus_read_byte(client); + if (ret < 0) { + dev_err(&client->dev, "failed reading\n"); + return ret; + } + + *val = (uint8_t)ret; + return 0; +} + +static inline int is_group_a(struct max732x_chip *chip, unsigned off) +{ + return (1u << off) & chip->mask_group_a; +} + +static int max732x_gpio_get_value(struct gpio_chip *gc, unsigned off) +{ + struct max732x_chip *chip = gpiochip_get_data(gc); + uint8_t reg_val; + int ret; + + ret = max732x_readb(chip, is_group_a(chip, off), ®_val); + if (ret < 0) + return ret; + + return !!(reg_val & (1u << (off & 0x7))); +} + +static void max732x_gpio_set_mask(struct gpio_chip *gc, unsigned off, int mask, + int val) +{ + struct max732x_chip *chip = gpiochip_get_data(gc); + uint8_t reg_out; + int ret; + + mutex_lock(&chip->lock); + + reg_out = (off > 7) ? chip->reg_out[1] : chip->reg_out[0]; + reg_out = (reg_out & ~mask) | (val & mask); + + ret = max732x_writeb(chip, is_group_a(chip, off), reg_out); + if (ret < 0) + goto out; + + /* update the shadow register then */ + if (off > 7) + chip->reg_out[1] = reg_out; + else + chip->reg_out[0] = reg_out; +out: + mutex_unlock(&chip->lock); +} + +static void max732x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val) +{ + unsigned base = off & ~0x7; + uint8_t mask = 1u << (off & 0x7); + + max732x_gpio_set_mask(gc, base, mask, val << (off & 0x7)); +} + +static void max732x_gpio_set_multiple(struct gpio_chip *gc, + unsigned long *mask, unsigned long *bits) +{ + unsigned mask_lo = mask[0] & 0xff; + unsigned mask_hi = (mask[0] >> 8) & 0xff; + + if (mask_lo) + max732x_gpio_set_mask(gc, 0, mask_lo, bits[0] & 0xff); + if (mask_hi) + max732x_gpio_set_mask(gc, 8, mask_hi, (bits[0] >> 8) & 0xff); +} + +static int max732x_gpio_direction_input(struct gpio_chip *gc, unsigned off) +{ + struct max732x_chip *chip = gpiochip_get_data(gc); + unsigned int mask = 1u << off; + + if ((mask & chip->dir_input) == 0) { + dev_dbg(&chip->client->dev, "%s port %d is output only\n", + chip->client->name, off); + return -EACCES; + } + + /* + * Open-drain pins must be set to high impedance (which is + * equivalent to output-high) to be turned into an input. + */ + if ((mask & chip->dir_output)) + max732x_gpio_set_value(gc, off, 1); + + return 0; +} + +static int max732x_gpio_direction_output(struct gpio_chip *gc, + unsigned off, int val) +{ + struct max732x_chip *chip = gpiochip_get_data(gc); + unsigned int mask = 1u << off; + + if ((mask & chip->dir_output) == 0) { + dev_dbg(&chip->client->dev, "%s port %d is input only\n", + chip->client->name, off); + return -EACCES; + } + + max732x_gpio_set_value(gc, off, val); + return 0; +} + +#ifdef CONFIG_GPIO_MAX732X_IRQ +static int max732x_writew(struct max732x_chip *chip, uint16_t val) +{ + int ret; + + val = cpu_to_le16(val); + + ret = i2c_master_send(chip->client_group_a, (char *)&val, 2); + if (ret < 0) { + dev_err(&chip->client_group_a->dev, "failed writing\n"); + return ret; + } + + return 0; +} + +static int max732x_readw(struct max732x_chip *chip, uint16_t *val) +{ + int ret; + + ret = i2c_master_recv(chip->client_group_a, (char *)val, 2); + if (ret < 0) { + dev_err(&chip->client_group_a->dev, "failed reading\n"); + return ret; + } + + *val = le16_to_cpu(*val); + return 0; +} + +static void max732x_irq_update_mask(struct max732x_chip *chip) +{ + uint16_t msg; + + if (chip->irq_mask == chip->irq_mask_cur) + return; + + chip->irq_mask = chip->irq_mask_cur; + + if (chip->irq_features == INT_NO_MASK) + return; + + mutex_lock(&chip->lock); + + switch (chip->irq_features) { + case INT_INDEP_MASK: + msg = (chip->irq_mask << 8) | chip->reg_out[0]; + max732x_writew(chip, msg); + break; + + case INT_MERGED_MASK: + msg = chip->irq_mask | chip->reg_out[0]; + max732x_writeb(chip, 1, (uint8_t)msg); + break; + } + + mutex_unlock(&chip->lock); +} + +static void max732x_irq_mask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct max732x_chip *chip = gpiochip_get_data(gc); + + chip->irq_mask_cur &= ~(1 << d->hwirq); +} + +static void max732x_irq_unmask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct max732x_chip *chip = gpiochip_get_data(gc); + + chip->irq_mask_cur |= 1 << d->hwirq; +} + +static void max732x_irq_bus_lock(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct max732x_chip *chip = gpiochip_get_data(gc); + + mutex_lock(&chip->irq_lock); + chip->irq_mask_cur = chip->irq_mask; +} + +static void max732x_irq_bus_sync_unlock(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct max732x_chip *chip = gpiochip_get_data(gc); + uint16_t new_irqs; + uint16_t level; + + max732x_irq_update_mask(chip); + + new_irqs = chip->irq_trig_fall | chip->irq_trig_raise; + while (new_irqs) { + level = __ffs(new_irqs); + max732x_gpio_direction_input(&chip->gpio_chip, level); + new_irqs &= ~(1 << level); + } + + mutex_unlock(&chip->irq_lock); +} + +static int max732x_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct max732x_chip *chip = gpiochip_get_data(gc); + uint16_t off = d->hwirq; + uint16_t mask = 1 << off; + + if (!(mask & chip->dir_input)) { + dev_dbg(&chip->client->dev, "%s port %d is output only\n", + chip->client->name, off); + return -EACCES; + } + + if (!(type & IRQ_TYPE_EDGE_BOTH)) { + dev_err(&chip->client->dev, "irq %d: unsupported type %d\n", + d->irq, type); + return -EINVAL; + } + + if (type & IRQ_TYPE_EDGE_FALLING) + chip->irq_trig_fall |= mask; + else + chip->irq_trig_fall &= ~mask; + + if (type & IRQ_TYPE_EDGE_RISING) + chip->irq_trig_raise |= mask; + else + chip->irq_trig_raise &= ~mask; + + return 0; +} + +static int max732x_irq_set_wake(struct irq_data *data, unsigned int on) +{ + struct max732x_chip *chip = irq_data_get_irq_chip_data(data); + + irq_set_irq_wake(chip->client->irq, on); + return 0; +} + +static struct irq_chip max732x_irq_chip = { + .name = "max732x", + .irq_mask = max732x_irq_mask, + .irq_unmask = max732x_irq_unmask, + .irq_bus_lock = max732x_irq_bus_lock, + .irq_bus_sync_unlock = max732x_irq_bus_sync_unlock, + .irq_set_type = max732x_irq_set_type, + .irq_set_wake = max732x_irq_set_wake, +}; + +static uint8_t max732x_irq_pending(struct max732x_chip *chip) +{ + uint8_t cur_stat; + uint8_t old_stat; + uint8_t trigger; + uint8_t pending; + uint16_t status; + int ret; + + ret = max732x_readw(chip, &status); + if (ret) + return 0; + + trigger = status >> 8; + trigger &= chip->irq_mask; + + if (!trigger) + return 0; + + cur_stat = status & 0xFF; + cur_stat &= chip->irq_mask; + + old_stat = cur_stat ^ trigger; + + pending = (old_stat & chip->irq_trig_fall) | + (cur_stat & chip->irq_trig_raise); + pending &= trigger; + + return pending; +} + +static irqreturn_t max732x_irq_handler(int irq, void *devid) +{ + struct max732x_chip *chip = devid; + uint8_t pending; + uint8_t level; + + pending = max732x_irq_pending(chip); + + if (!pending) + return IRQ_HANDLED; + + do { + level = __ffs(pending); + handle_nested_irq(irq_find_mapping(chip->gpio_chip.irq.domain, + level)); + + pending &= ~(1 << level); + } while (pending); + + return IRQ_HANDLED; +} + +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; + int irq_base = 0; + int ret; + + if (client->irq && has_irq != INT_NONE) { + struct gpio_irq_chip *girq; + + chip->irq_features = has_irq; + mutex_init(&chip->irq_lock); + + ret = devm_request_threaded_irq(&client->dev, client->irq, + NULL, max732x_irq_handler, IRQF_ONESHOT | + IRQF_TRIGGER_FALLING | IRQF_SHARED, + dev_name(&client->dev), chip); + if (ret) { + dev_err(&client->dev, "failed to request irq %d\n", + client->irq); + return ret; + } + + girq = &chip->gpio_chip.irq; + girq->chip = &max732x_irq_chip; + /* This will let us handle the parent IRQ in the driver */ + girq->parent_handler = NULL; + girq->num_parents = 0; + girq->parents = NULL; + girq->default_type = IRQ_TYPE_NONE; + girq->handler = handle_simple_irq; + girq->threaded = true; + girq->first = irq_base; /* FIXME: get rid of this */ + } + + return 0; +} + +#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) +{ + struct gpio_chip *gc = &chip->gpio_chip; + uint32_t id_data = (uint32_t)max732x_features[id->driver_data]; + int i, port = 0; + + for (i = 0; i < 16; i++, id_data >>= 2) { + unsigned int mask = 1 << port; + + switch (id_data & 0x3) { + case PORT_OUTPUT: + chip->dir_output |= mask; + break; + case PORT_INPUT: + chip->dir_input |= mask; + break; + case PORT_OPENDRAIN: + chip->dir_output |= mask; + chip->dir_input |= mask; + break; + default: + continue; + } + + if (i < 8) + chip->mask_group_a |= mask; + port++; + } + + if (chip->dir_input) + gc->direction_input = max732x_gpio_direction_input; + if (chip->dir_output) { + gc->direction_output = max732x_gpio_direction_output; + gc->set = max732x_gpio_set_value; + gc->set_multiple = max732x_gpio_set_multiple; + } + gc->get = max732x_gpio_get_value; + gc->can_sleep = true; + + gc->base = gpio_start; + gc->ngpio = port; + gc->label = chip->client->name; + gc->parent = &chip->client->dev; + gc->owner = THIS_MODULE; + + return port; +} + +static struct max732x_platform_data *of_gpio_max732x(struct device *dev) +{ + struct max732x_platform_data *pdata; + + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return NULL; + + pdata->gpio_base = -1; + + return pdata; +} + +static int max732x_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct max732x_platform_data *pdata; + struct device_node *node; + struct max732x_chip *chip; + struct i2c_client *c; + uint16_t addr_a, addr_b; + int ret, nr_port; + + pdata = dev_get_platdata(&client->dev); + node = client->dev.of_node; + + if (!pdata && node) + pdata = of_gpio_max732x(&client->dev); + + if (!pdata) { + dev_dbg(&client->dev, "no platform data\n"); + return -EINVAL; + } + + chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); + if (chip == NULL) + return -ENOMEM; + chip->client = client; + + nr_port = max732x_setup_gpio(chip, id, pdata->gpio_base); + chip->gpio_chip.parent = &client->dev; + + addr_a = (client->addr & 0x0f) | 0x60; + addr_b = (client->addr & 0x0f) | 0x50; + + switch (client->addr & 0x70) { + case 0x60: + chip->client_group_a = client; + if (nr_port > 8) { + c = devm_i2c_new_dummy_device(&client->dev, + client->adapter, addr_b); + if (IS_ERR(c)) { + dev_err(&client->dev, + "Failed to allocate I2C device\n"); + return PTR_ERR(c); + } + chip->client_group_b = chip->client_dummy = c; + } + break; + case 0x50: + chip->client_group_b = client; + if (nr_port > 8) { + c = devm_i2c_new_dummy_device(&client->dev, + client->adapter, addr_a); + if (IS_ERR(c)) { + dev_err(&client->dev, + "Failed to allocate I2C device\n"); + return PTR_ERR(c); + } + chip->client_group_a = chip->client_dummy = c; + } + break; + default: + dev_err(&client->dev, "invalid I2C address specified %02x\n", + client->addr); + return -EINVAL; + } + + if (nr_port > 8 && !chip->client_dummy) { + dev_err(&client->dev, + "Failed to allocate second group I2C device\n"); + return -ENODEV; + } + + mutex_init(&chip->lock); + + ret = max732x_readb(chip, is_group_a(chip, 0), &chip->reg_out[0]); + if (ret) + return ret; + if (nr_port > 8) { + ret = max732x_readb(chip, is_group_a(chip, 8), &chip->reg_out[1]); + if (ret) + return ret; + } + + ret = max732x_irq_setup(chip, id); + if (ret) + return ret; + + ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip); + if (ret) + return ret; + + i2c_set_clientdata(client, chip); + return 0; +} + +static struct i2c_driver max732x_driver = { + .driver = { + .name = "max732x", + .of_match_table = of_match_ptr(max732x_of_table), + }, + .probe = max732x_probe, + .id_table = max732x_id, +}; + +static int __init max732x_init(void) +{ + return i2c_add_driver(&max732x_driver); +} +/* 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) +{ + i2c_del_driver(&max732x_driver); +} +module_exit(max732x_exit); + +MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>"); +MODULE_DESCRIPTION("GPIO expander driver for MAX732X"); +MODULE_LICENSE("GPL"); |