linux/drivers/gpio/gpio-adp5588.c

504 lines
12 KiB
C

/*
* GPIO Chip driver for Analog Devices
* ADP5588/ADP5587 I/O Expander and QWERTY Keypad Controller
*
* Copyright 2009-2010 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/i2c/adp5588.h>
#define DRV_NAME "adp5588-gpio"
/*
* Early pre 4.0 Silicon required to delay readout by at least 25ms,
* since the Event Counter Register updated 25ms after the interrupt
* asserted.
*/
#define WA_DELAYED_READOUT_REVID(rev) ((rev) < 4)
struct adp5588_gpio {
struct i2c_client *client;
struct gpio_chip gpio_chip;
struct mutex lock; /* protect cached dir, dat_out */
/* protect serialized access to the interrupt controller bus */
struct mutex irq_lock;
unsigned gpio_start;
unsigned irq_base;
uint8_t dat_out[3];
uint8_t dir[3];
uint8_t int_lvl[3];
uint8_t int_en[3];
uint8_t irq_mask[3];
uint8_t irq_stat[3];
};
static int adp5588_gpio_read(struct i2c_client *client, u8 reg)
{
int ret = i2c_smbus_read_byte_data(client, reg);
if (ret < 0)
dev_err(&client->dev, "Read Error\n");
return ret;
}
static int adp5588_gpio_write(struct i2c_client *client, u8 reg, u8 val)
{
int ret = i2c_smbus_write_byte_data(client, reg, val);
if (ret < 0)
dev_err(&client->dev, "Write Error\n");
return ret;
}
static int adp5588_gpio_get_value(struct gpio_chip *chip, unsigned off)
{
struct adp5588_gpio *dev =
container_of(chip, struct adp5588_gpio, gpio_chip);
unsigned bank = ADP5588_BANK(off);
unsigned bit = ADP5588_BIT(off);
int val;
mutex_lock(&dev->lock);
if (dev->dir[bank] & bit)
val = dev->dat_out[bank];
else
val = adp5588_gpio_read(dev->client, GPIO_DAT_STAT1 + bank);
mutex_unlock(&dev->lock);
return !!(val & bit);
}
static void adp5588_gpio_set_value(struct gpio_chip *chip,
unsigned off, int val)
{
unsigned bank, bit;
struct adp5588_gpio *dev =
container_of(chip, struct adp5588_gpio, gpio_chip);
bank = ADP5588_BANK(off);
bit = ADP5588_BIT(off);
mutex_lock(&dev->lock);
if (val)
dev->dat_out[bank] |= bit;
else
dev->dat_out[bank] &= ~bit;
adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank,
dev->dat_out[bank]);
mutex_unlock(&dev->lock);
}
static int adp5588_gpio_direction_input(struct gpio_chip *chip, unsigned off)
{
int ret;
unsigned bank;
struct adp5588_gpio *dev =
container_of(chip, struct adp5588_gpio, gpio_chip);
bank = ADP5588_BANK(off);
mutex_lock(&dev->lock);
dev->dir[bank] &= ~ADP5588_BIT(off);
ret = adp5588_gpio_write(dev->client, GPIO_DIR1 + bank, dev->dir[bank]);
mutex_unlock(&dev->lock);
return ret;
}
static int adp5588_gpio_direction_output(struct gpio_chip *chip,
unsigned off, int val)
{
int ret;
unsigned bank, bit;
struct adp5588_gpio *dev =
container_of(chip, struct adp5588_gpio, gpio_chip);
bank = ADP5588_BANK(off);
bit = ADP5588_BIT(off);
mutex_lock(&dev->lock);
dev->dir[bank] |= bit;
if (val)
dev->dat_out[bank] |= bit;
else
dev->dat_out[bank] &= ~bit;
ret = adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank,
dev->dat_out[bank]);
ret |= adp5588_gpio_write(dev->client, GPIO_DIR1 + bank,
dev->dir[bank]);
mutex_unlock(&dev->lock);
return ret;
}
#ifdef CONFIG_GPIO_ADP5588_IRQ
static int adp5588_gpio_to_irq(struct gpio_chip *chip, unsigned off)
{
struct adp5588_gpio *dev =
container_of(chip, struct adp5588_gpio, gpio_chip);
return dev->irq_base + off;
}
static void adp5588_irq_bus_lock(struct irq_data *d)
{
struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
mutex_lock(&dev->irq_lock);
}
/*
* genirq core code can issue chip->mask/unmask from atomic context.
* This doesn't work for slow busses where an access needs to sleep.
* bus_sync_unlock() is therefore called outside the atomic context,
* syncs the current irq mask state with the slow external controller
* and unlocks the bus.
*/
static void adp5588_irq_bus_sync_unlock(struct irq_data *d)
{
struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
int i;
for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++)
if (dev->int_en[i] ^ dev->irq_mask[i]) {
dev->int_en[i] = dev->irq_mask[i];
adp5588_gpio_write(dev->client, GPIO_INT_EN1 + i,
dev->int_en[i]);
}
mutex_unlock(&dev->irq_lock);
}
static void adp5588_irq_mask(struct irq_data *d)
{
struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
unsigned gpio = d->irq - dev->irq_base;
dev->irq_mask[ADP5588_BANK(gpio)] &= ~ADP5588_BIT(gpio);
}
static void adp5588_irq_unmask(struct irq_data *d)
{
struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
unsigned gpio = d->irq - dev->irq_base;
dev->irq_mask[ADP5588_BANK(gpio)] |= ADP5588_BIT(gpio);
}
static int adp5588_irq_set_type(struct irq_data *d, unsigned int type)
{
struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
uint16_t gpio = d->irq - dev->irq_base;
unsigned bank, bit;
if ((type & IRQ_TYPE_EDGE_BOTH)) {
dev_err(&dev->client->dev, "irq %d: unsupported type %d\n",
d->irq, type);
return -EINVAL;
}
bank = ADP5588_BANK(gpio);
bit = ADP5588_BIT(gpio);
if (type & IRQ_TYPE_LEVEL_HIGH)
dev->int_lvl[bank] |= bit;
else if (type & IRQ_TYPE_LEVEL_LOW)
dev->int_lvl[bank] &= ~bit;
else
return -EINVAL;
adp5588_gpio_direction_input(&dev->gpio_chip, gpio);
adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + bank,
dev->int_lvl[bank]);
return 0;
}
static struct irq_chip adp5588_irq_chip = {
.name = "adp5588",
.irq_mask = adp5588_irq_mask,
.irq_unmask = adp5588_irq_unmask,
.irq_bus_lock = adp5588_irq_bus_lock,
.irq_bus_sync_unlock = adp5588_irq_bus_sync_unlock,
.irq_set_type = adp5588_irq_set_type,
};
static int adp5588_gpio_read_intstat(struct i2c_client *client, u8 *buf)
{
int ret = i2c_smbus_read_i2c_block_data(client, GPIO_INT_STAT1, 3, buf);
if (ret < 0)
dev_err(&client->dev, "Read INT_STAT Error\n");
return ret;
}
static irqreturn_t adp5588_irq_handler(int irq, void *devid)
{
struct adp5588_gpio *dev = devid;
unsigned status, bank, bit, pending;
int ret;
status = adp5588_gpio_read(dev->client, INT_STAT);
if (status & ADP5588_GPI_INT) {
ret = adp5588_gpio_read_intstat(dev->client, dev->irq_stat);
if (ret < 0)
memset(dev->irq_stat, 0, ARRAY_SIZE(dev->irq_stat));
for (bank = 0, bit = 0; bank <= ADP5588_BANK(ADP5588_MAXGPIO);
bank++, bit = 0) {
pending = dev->irq_stat[bank] & dev->irq_mask[bank];
while (pending) {
if (pending & (1 << bit)) {
handle_nested_irq(dev->irq_base +
(bank << 3) + bit);
pending &= ~(1 << bit);
}
bit++;
}
}
}
adp5588_gpio_write(dev->client, INT_STAT, status); /* Status is W1C */
return IRQ_HANDLED;
}
static int adp5588_irq_setup(struct adp5588_gpio *dev)
{
struct i2c_client *client = dev->client;
struct adp5588_gpio_platform_data *pdata =
dev_get_platdata(&client->dev);
unsigned gpio;
int ret;
adp5588_gpio_write(client, CFG, ADP5588_AUTO_INC);
adp5588_gpio_write(client, INT_STAT, -1); /* status is W1C */
adp5588_gpio_read_intstat(client, dev->irq_stat); /* read to clear */
dev->irq_base = pdata->irq_base;
mutex_init(&dev->irq_lock);
for (gpio = 0; gpio < dev->gpio_chip.ngpio; gpio++) {
int irq = gpio + dev->irq_base;
irq_set_chip_data(irq, dev);
irq_set_chip_and_handler(irq, &adp5588_irq_chip,
handle_level_irq);
irq_set_nested_thread(irq, 1);
#ifdef CONFIG_ARM
/*
* ARM needs us to explicitly flag the IRQ as VALID,
* once we do so, it will also set the noprobe.
*/
set_irq_flags(irq, IRQF_VALID);
#else
irq_set_noprobe(irq);
#endif
}
ret = request_threaded_irq(client->irq,
NULL,
adp5588_irq_handler,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
dev_name(&client->dev), dev);
if (ret) {
dev_err(&client->dev, "failed to request irq %d\n",
client->irq);
goto out;
}
dev->gpio_chip.to_irq = adp5588_gpio_to_irq;
adp5588_gpio_write(client, CFG,
ADP5588_AUTO_INC | ADP5588_INT_CFG | ADP5588_GPI_INT);
return 0;
out:
dev->irq_base = 0;
return ret;
}
static void adp5588_irq_teardown(struct adp5588_gpio *dev)
{
if (dev->irq_base)
free_irq(dev->client->irq, dev);
}
#else
static int adp5588_irq_setup(struct adp5588_gpio *dev)
{
struct i2c_client *client = dev->client;
dev_warn(&client->dev, "interrupt support not compiled in\n");
return 0;
}
static void adp5588_irq_teardown(struct adp5588_gpio *dev)
{
}
#endif /* CONFIG_GPIO_ADP5588_IRQ */
static int adp5588_gpio_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct adp5588_gpio_platform_data *pdata =
dev_get_platdata(&client->dev);
struct adp5588_gpio *dev;
struct gpio_chip *gc;
int ret, i, revid;
if (pdata == NULL) {
dev_err(&client->dev, "missing platform data\n");
return -ENODEV;
}
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_BYTE_DATA)) {
dev_err(&client->dev, "SMBUS Byte Data not Supported\n");
return -EIO;
}
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (dev == NULL)
return -ENOMEM;
dev->client = client;
gc = &dev->gpio_chip;
gc->direction_input = adp5588_gpio_direction_input;
gc->direction_output = adp5588_gpio_direction_output;
gc->get = adp5588_gpio_get_value;
gc->set = adp5588_gpio_set_value;
gc->can_sleep = true;
gc->base = pdata->gpio_start;
gc->ngpio = ADP5588_MAXGPIO;
gc->label = client->name;
gc->owner = THIS_MODULE;
gc->names = pdata->names;
mutex_init(&dev->lock);
ret = adp5588_gpio_read(dev->client, DEV_ID);
if (ret < 0)
goto err;
revid = ret & ADP5588_DEVICE_ID_MASK;
for (i = 0, ret = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) {
dev->dat_out[i] = adp5588_gpio_read(client, GPIO_DAT_OUT1 + i);
dev->dir[i] = adp5588_gpio_read(client, GPIO_DIR1 + i);
ret |= adp5588_gpio_write(client, KP_GPIO1 + i, 0);
ret |= adp5588_gpio_write(client, GPIO_PULL1 + i,
(pdata->pullup_dis_mask >> (8 * i)) & 0xFF);
ret |= adp5588_gpio_write(client, GPIO_INT_EN1 + i, 0);
if (ret)
goto err;
}
if (pdata->irq_base) {
if (WA_DELAYED_READOUT_REVID(revid)) {
dev_warn(&client->dev, "GPIO int not supported\n");
} else {
ret = adp5588_irq_setup(dev);
if (ret)
goto err;
}
}
ret = gpiochip_add(&dev->gpio_chip);
if (ret)
goto err_irq;
dev_info(&client->dev, "IRQ Base: %d Rev.: %d\n",
pdata->irq_base, revid);
if (pdata->setup) {
ret = pdata->setup(client, gc->base, gc->ngpio, pdata->context);
if (ret < 0)
dev_warn(&client->dev, "setup failed, %d\n", ret);
}
i2c_set_clientdata(client, dev);
return 0;
err_irq:
adp5588_irq_teardown(dev);
err:
kfree(dev);
return ret;
}
static int adp5588_gpio_remove(struct i2c_client *client)
{
struct adp5588_gpio_platform_data *pdata =
dev_get_platdata(&client->dev);
struct adp5588_gpio *dev = i2c_get_clientdata(client);
int ret;
if (pdata->teardown) {
ret = pdata->teardown(client,
dev->gpio_chip.base, dev->gpio_chip.ngpio,
pdata->context);
if (ret < 0) {
dev_err(&client->dev, "teardown failed %d\n", ret);
return ret;
}
}
if (dev->irq_base)
free_irq(dev->client->irq, dev);
ret = gpiochip_remove(&dev->gpio_chip);
if (ret) {
dev_err(&client->dev, "gpiochip_remove failed %d\n", ret);
return ret;
}
kfree(dev);
return 0;
}
static const struct i2c_device_id adp5588_gpio_id[] = {
{DRV_NAME, 0},
{}
};
MODULE_DEVICE_TABLE(i2c, adp5588_gpio_id);
static struct i2c_driver adp5588_gpio_driver = {
.driver = {
.name = DRV_NAME,
},
.probe = adp5588_gpio_probe,
.remove = adp5588_gpio_remove,
.id_table = adp5588_gpio_id,
};
module_i2c_driver(adp5588_gpio_driver);
MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("GPIO ADP5588 Driver");
MODULE_LICENSE("GPL");