linux/drivers/gpio/gpio-max732x.c
Linus Torvalds 2ec98f5678 Bulk GPIO changes for the v5.3 kernel cycle:
Core:
 
 - When a gpio_chip request GPIOs from itself, it can now fully
   control the line characteristics, both machine and consumer
   flags. This makes a lot of sense, but took some time before I
   figured out that this is how it has to work.
 
 - Several smallish documentation fixes.
 
 New drivers:
 
 - The PCA953x driver now supports the TI TCA9539.
 
 - The DaVinci driver now supports the K3 AM654 SoCs.
 
 Driver improvements:
 
 - Major overhaul and hardening of the OMAP driver by Russell
   King.
 
 - Starting to move some drivers to the new API passing irq_chip
   along with the gpio_chip when adding the gpio_chip instead
   of adding it separately.
 
 Unrelated:
 
 - Delete the FMC subsystem.
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Merge tag 'gpio-v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the big slew of GPIO changes for the v5.3 kernel cycle. This
  is mostly incremental work this time.

  Three important things:

   - The FMC subsystem is deleted through my tree. This happens through
     GPIO as its demise was discussed in relation to a patch decoupling
     its GPIO implementation from the standard way of handling GPIO. As
     it turns out, that is not the only subsystem it reimplements and
     the authors think it is better do scratch it and start over using
     the proper kernel subsystems than try to polish the rust shiny. See
     the commit (ACKed by the maintainers) for details.

   - Arnd made a small devres patch that was ACKed by Greg and goes into
     the device core.

   - SPDX header change colissions may happen, because at times I've
     seen that quite a lot changed during the -rc:s in regards to SPDX.
     (It is good stuff, tglx has me convinced, and it is worth the
     occasional pain.)

  Apart from this is is nothing controversial or problematic.

  Summary:

  Core:

   - When a gpio_chip request GPIOs from itself, it can now fully
     control the line characteristics, both machine and consumer flags.
     This makes a lot of sense, but took some time before I figured out
     that this is how it has to work.

   - Several smallish documentation fixes.

  New drivers:

   - The PCA953x driver now supports the TI TCA9539.

   - The DaVinci driver now supports the K3 AM654 SoCs.

  Driver improvements:

   - Major overhaul and hardening of the OMAP driver by Russell King.

   - Starting to move some drivers to the new API passing irq_chip along
     with the gpio_chip when adding the gpio_chip instead of adding it
     separately.

  Unrelated:

   - Delete the FMC subsystem"

* tag 'gpio-v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (87 commits)
  Revert "gpio: tegra: Clean-up debugfs initialisation"
  gpiolib: Use spinlock_t instead of struct spinlock
  gpio: stp-xway: allow compile-testing
  gpio: stp-xway: get rid of the #include <lantiq_soc.h> dependency
  gpio: stp-xway: improve module clock error handling
  gpio: stp-xway: simplify error handling in xway_stp_probe()
  gpiolib: Clarify use of non-sleeping functions
  gpiolib: Fix references to gpiod_[gs]et_*value_cansleep() variants
  gpiolib: Document new gpio_chip.init_valid_mask field
  Documentation: gpio: Fix reference to gpiod_get_array()
  gpio: pl061: drop duplicate printing of device name
  gpio: altera: Pass irqchip when adding gpiochip
  gpio: siox: Use devm_ managed gpiochip
  gpio: siox: Add struct device *dev helper variable
  gpio: siox: Pass irqchip when adding gpiochip
  drivers: gpio: amd-fch: make resource struct const
  devres: allow const resource arguments
  gpio: ath79: Pass irqchip when adding gpiochip
  gpio: tegra: Clean-up debugfs initialisation
  gpio: siox: Switch to IRQ_TYPE_NONE
  ...
2019-07-09 09:07:00 -07:00

765 lines
18 KiB
C

// 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), &reg_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;
struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
int has_irq = max732x_features[id->driver_data] >> 32;
int irq_base = 0;
int ret;
if (((pdata && pdata->irq_base) || client->irq)
&& has_irq != INT_NONE) {
if (pdata)
irq_base = pdata->irq_base;
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;
}
ret = gpiochip_irqchip_add_nested(&chip->gpio_chip,
&max732x_irq_chip,
irq_base,
handle_simple_irq,
IRQ_TYPE_NONE);
if (ret) {
dev_err(&client->dev,
"could not connect irqchip to gpiochip\n");
return ret;
}
gpiochip_set_nested_irqchip(&chip->gpio_chip,
&max732x_irq_chip,
client->irq);
}
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;
struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
int has_irq = max732x_features[id->driver_data] >> 32;
if (((pdata && pdata->irq_base) || 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 = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
if (ret)
return ret;
ret = max732x_irq_setup(chip, id);
if (ret)
return ret;
if (pdata && pdata->setup) {
ret = pdata->setup(client, chip->gpio_chip.base,
chip->gpio_chip.ngpio, pdata->context);
if (ret < 0)
dev_warn(&client->dev, "setup failed, %d\n", ret);
}
i2c_set_clientdata(client, chip);
return 0;
}
static int max732x_remove(struct i2c_client *client)
{
struct max732x_platform_data *pdata = dev_get_platdata(&client->dev);
struct max732x_chip *chip = i2c_get_clientdata(client);
if (pdata && pdata->teardown) {
int ret;
ret = pdata->teardown(client, chip->gpio_chip.base,
chip->gpio_chip.ngpio, pdata->context);
if (ret < 0) {
dev_err(&client->dev, "%s failed, %d\n",
"teardown", ret);
return ret;
}
}
return 0;
}
static struct i2c_driver max732x_driver = {
.driver = {
.name = "max732x",
.of_match_table = of_match_ptr(max732x_of_table),
},
.probe = max732x_probe,
.remove = max732x_remove,
.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");