// SPDX-License-Identifier: GPL-2.0-only
/*
* PCA953x 4/8/16/24/40 bit I/O ports
*
* Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
* Copyright (C) 2007 Marvell International Ltd.
*
* Derived from drivers/i2c/chips/pca9539.c
*/
#include <linux/acpi.h>
#include <linux/bitmap.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_data/pca953x.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <asm/unaligned.h>
#define PCA953X_INPUT 0x00
#define PCA953X_OUTPUT 0x01
#define PCA953X_INVERT 0x02
#define PCA953X_DIRECTION 0x03
#define REG_ADDR_MASK GENMASK(5, 0)
#define REG_ADDR_EXT BIT(6)
#define REG_ADDR_AI BIT(7)
#define PCA957X_IN 0x00
#define PCA957X_INVRT 0x01
#define PCA957X_BKEN 0x02
#define PCA957X_PUPD 0x03
#define PCA957X_CFG 0x04
#define PCA957X_OUT 0x05
#define PCA957X_MSK 0x06
#define PCA957X_INTS 0x07
#define PCAL953X_OUT_STRENGTH 0x20
#define PCAL953X_IN_LATCH 0x22
#define PCAL953X_PULL_EN 0x23
#define PCAL953X_PULL_SEL 0x24
#define PCAL953X_INT_MASK 0x25
#define PCAL953X_INT_STAT 0x26
#define PCAL953X_OUT_CONF 0x27
#define PCAL6524_INT_EDGE 0x28
#define PCAL6524_INT_CLR 0x2a
#define PCAL6524_IN_STATUS 0x2b
#define PCAL6524_OUT_INDCONF 0x2c
#define PCAL6524_DEBOUNCE 0x2d
#define PCA_GPIO_MASK GENMASK(7, 0)
#define PCAL_GPIO_MASK GENMASK(4, 0)
#define PCAL_PINCTRL_MASK GENMASK(6, 5)
#define PCA_INT BIT(8)
#define PCA_PCAL BIT(9)
#define PCA_LATCH_INT (PCA_PCAL | PCA_INT)
#define PCA953X_TYPE BIT(12)
#define PCA957X_TYPE BIT(13)
#define PCAL653X_TYPE BIT(14)
#define PCA_TYPE_MASK GENMASK(15, 12)
#define PCA_CHIP_TYPE(x) ((x) & PCA_TYPE_MASK)
static const struct i2c_device_id pca953x_id[] = {
{ "pca6408", 8 | PCA953X_TYPE | PCA_INT, },
{ "pca6416", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca9505", 40 | PCA953X_TYPE | PCA_INT, },
{ "pca9506", 40 | PCA953X_TYPE | PCA_INT, },
{ "pca9534", 8 | PCA953X_TYPE | PCA_INT, },
{ "pca9535", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca9536", 4 | PCA953X_TYPE, },
{ "pca9537", 4 | PCA953X_TYPE | PCA_INT, },
{ "pca9538", 8 | PCA953X_TYPE | PCA_INT, },
{ "pca9539", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca9554", 8 | PCA953X_TYPE | PCA_INT, },
{ "pca9555", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca9556", 8 | PCA953X_TYPE, },
{ "pca9557", 8 | PCA953X_TYPE, },
{ "pca9574", 8 | PCA957X_TYPE | PCA_INT, },
{ "pca9575", 16 | PCA957X_TYPE | PCA_INT, },
{ "pca9698", 40 | PCA953X_TYPE, },
{ "pcal6408", 8 | PCA953X_TYPE | PCA_LATCH_INT, },
{ "pcal6416", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
{ "pcal6524", 24 | PCA953X_TYPE | PCA_LATCH_INT, },
{ "pcal6534", 34 | PCAL653X_TYPE | PCA_LATCH_INT, },
{ "pcal9535", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
{ "pcal9554b", 8 | PCA953X_TYPE | PCA_LATCH_INT, },
{ "pcal9555a", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
{ "max7310", 8 | PCA953X_TYPE, },
{ "max7312", 16 | PCA953X_TYPE | PCA_INT, },
{ "max7313", 16 | PCA953X_TYPE | PCA_INT, },
{ "max7315", 8 | PCA953X_TYPE | PCA_INT, },
{ "max7318", 16 | PCA953X_TYPE | PCA_INT, },
{ "pca6107", 8 | PCA953X_TYPE | PCA_INT, },
{ "tca6408", 8 | PCA953X_TYPE | PCA_INT, },
{ "tca6416", 16 | PCA953X_TYPE | PCA_INT, },
{ "tca6424", 24 | PCA953X_TYPE | PCA_INT, },
{ "tca9539", 16 | PCA953X_TYPE | PCA_INT, },
{ "tca9554", 8 | PCA953X_TYPE | PCA_INT, },
{ "xra1202", 8 | PCA953X_TYPE },
{ }
};
MODULE_DEVICE_TABLE(i2c, pca953x_id);
#ifdef CONFIG_GPIO_PCA953X_IRQ
#include <linux/dmi.h>
static const struct acpi_gpio_params pca953x_irq_gpios = { 0, 0, true };
static const struct acpi_gpio_mapping pca953x_acpi_irq_gpios[] = {
{ "irq-gpios", &pca953x_irq_gpios, 1, ACPI_GPIO_QUIRK_ABSOLUTE_NUMBER },
{ }
};
static int pca953x_acpi_get_irq(struct device *dev)
{
int ret;
ret = devm_acpi_dev_add_driver_gpios(dev, pca953x_acpi_irq_gpios);
if (ret)
dev_warn(dev, "can't add GPIO ACPI mapping\n");
ret = acpi_dev_gpio_irq_get_by(ACPI_COMPANION(dev), "irq-gpios", 0);
if (ret < 0)
return ret;
dev_info(dev, "ACPI interrupt quirk (IRQ %d)\n", ret);
return ret;
}
static const struct dmi_system_id pca953x_dmi_acpi_irq_info[] = {
{
/*
* On Intel Galileo Gen 2 board the IRQ pin of one of
* the I²C GPIO expanders, which has GpioInt() resource,
* is provided as an absolute number instead of being
* relative. Since first controller (gpio-sch.c) and
* second (gpio-dwapb.c) are at the fixed bases, we may
* safely refer to the number in the global space to get
* an IRQ out of it.
*/
.matches = {
DMI_EXACT_MATCH(DMI_BOARD_NAME, "GalileoGen2"),
},
},
{}
};
#endif
static const struct acpi_device_id pca953x_acpi_ids[] = {
{ "INT3491", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
{ }
};
MODULE_DEVICE_TABLE(acpi, pca953x_acpi_ids);
#define MAX_BANK 5
#define BANK_SZ 8
#define MAX_LINE (MAX_BANK * BANK_SZ)
#define NBANK(chip) DIV_ROUND_UP(chip->gpio_chip.ngpio, BANK_SZ)
struct pca953x_reg_config {
int direction;
int output;
int input;
int invert;
};
static const struct pca953x_reg_config pca953x_regs = {
.direction = PCA953X_DIRECTION,
.output = PCA953X_OUTPUT,
.input = PCA953X_INPUT,
.invert = PCA953X_INVERT,
};
static const struct pca953x_reg_config pca957x_regs = {
.direction = PCA957X_CFG,
.output = PCA957X_OUT,
.input = PCA957X_IN,
.invert = PCA957X_INVRT,
};
struct pca953x_chip {
unsigned gpio_start;
struct mutex i2c_lock;
struct regmap *regmap;
#ifdef CONFIG_GPIO_PCA953X_IRQ
struct mutex irq_lock;
DECLARE_BITMAP(irq_mask, MAX_LINE);
DECLARE_BITMAP(irq_stat, MAX_LINE);
DECLARE_BITMAP(irq_trig_raise, MAX_LINE);
DECLARE_BITMAP(irq_trig_fall, MAX_LINE);
#endif
atomic_t wakeup_path;
struct i2c_client *client;
struct gpio_chip gpio_chip;
const char *const *names;
unsigned long driver_data;
struct regulator *regulator;
const struct pca953x_reg_config *regs;
u8 (*recalc_addr)(struct pca953x_chip *chip, int reg, int off);
bool (*check_reg)(struct pca953x_chip *chip, unsigned int reg,
u32 checkbank);
};
static int pca953x_bank_shift(struct pca953x_chip *chip)
{
return fls((chip->gpio_chip.ngpio - 1) / BANK_SZ);
}
#define PCA953x_BANK_INPUT BIT(0)
#define PCA953x_BANK_OUTPUT BIT(1)
#define PCA953x_BANK_POLARITY BIT(2)
#define PCA953x_BANK_CONFIG BIT(3)
#define PCA957x_BANK_INPUT BIT(0)
#define PCA957x_BANK_POLARITY BIT(1)
#define PCA957x_BANK_BUSHOLD BIT(2)
#define PCA957x_BANK_CONFIG BIT(4)
#define PCA957x_BANK_OUTPUT BIT(5)
#define PCAL9xxx_BANK_IN_LATCH BIT(8 + 2)
#define PCAL9xxx_BANK_PULL_EN BIT(8 + 3)
#define PCAL9xxx_BANK_PULL_SEL BIT(8 + 4)
#define PCAL9xxx_BANK_IRQ_MASK BIT(8 + 5)
#define PCAL9xxx_BANK_IRQ_STAT BIT(8 + 6)
/*
* We care about the following registers:
* - Standard set, below 0x40, each port can be replicated up to 8 times
* - PCA953x standard
* Input port 0x00 + 0 * bank_size R
* Output port 0x00 + 1 * bank_size RW
* Polarity Inversion port 0x00 + 2 * bank_size RW
* Configuration port 0x00 + 3 * bank_size RW
* - PCA957x with mixed up registers
* Input port 0x00 + 0 * bank_size R
* Polarity Inversion port 0x00 + 1 * bank_size RW
* Bus hold port 0x00 + 2 * bank_size RW
* Configuration port 0x00 + 4 * bank_size RW
* Output port 0x00 + 5 * bank_size RW
*
* - Extended set, above 0x40, often chip specific.
* - PCAL6524/PCAL9555A with custom PCAL IRQ handling:
* Input latch register 0x40 + 2 * bank_size RW
* Pull-up/pull-down enable reg 0x40 + 3 * bank_size RW
* Pull-up/pull-down select reg 0x40 + 4 * bank_size RW
* Interrupt mask register 0x40 + 5 * bank_size RW
* Interrupt status register 0x40 + 6 * bank_size R
*
* - Registers with bit 0x80 set, the AI bit
* The bit is cleared and the registers fall into one of the
* categories above.
*/
static bool pca953x_check_register(struct pca953x_chip *chip, unsigned int reg,
u32 checkbank)
{
int bank_shift = pca953x_bank_shift(chip);
int bank = (reg & REG_ADDR_MASK) >> bank_shift;
int offset = reg & (BIT(bank_shift) - 1);
/* Special PCAL extended register check. */
if (reg & REG_ADDR_EXT) {
if (!(chip->driver_data & PCA_PCAL))
return false;
bank += 8;
}
/* Register is not in the matching bank. */
if (!(BIT(bank) & checkbank))
return false;
/* Register is not within allowed range of bank. */
if (offset >= NBANK(chip))
return false;
return true;
}
/*
* Unfortunately, whilst the PCAL6534 chip (and compatibles) broadly follow the
* same register layout as the PCAL6524, the spacing of the registers has been
* fundamentally altered by compacting them and thus does not obey the same
* rules, including being able to use bit shifting to determine bank. These
* chips hence need special handling here.
*/
static bool pcal6534_check_register(struct pca953x_chip *chip, unsigned int reg,
u32 checkbank)
{
int bank;
int offset;
if (reg >= 0x30) {
/*
* Reserved block between 14h and 2Fh does not align on
* expected bank boundaries like other devices.
*/
int temp = reg - 0x30;
bank = temp / NBANK(chip);
offset = temp - (bank * NBANK(chip));
bank += 8;
} else if (reg >= 0x54) {
/*
* Handle lack of reserved registers after output port
* configuration register to form a bank.
*/
int temp = reg - 0x54;
bank = temp / NBANK(chip);
offset = temp - (bank * NBANK(chip));
bank += 16;
} else {
bank = reg / NBANK(chip);
offset = reg - (bank * NBANK(chip));
}
/* Register is not in the matching bank. */
if (!(BIT(bank) & checkbank))
return false;
/* Register is not within allowed range of bank. */
if (offset >= NBANK(chip))
return false;
return true;
}
static bool pca953x_readable_register(struct device *dev, unsigned int reg)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
u32 bank;
if (PCA_CHIP_TYPE(chip->driver_data) == PCA957X_TYPE) {
bank = PCA957x_BANK_INPUT | PCA957x_BANK_OUTPUT |
PCA957x_BANK_POLARITY | PCA957x_BANK_CONFIG |
PCA957x_BANK_BUSHOLD;
} else {
bank = PCA953x_BANK_INPUT | PCA953x_BANK_OUTPUT |
PCA953x_BANK_POLARITY | PCA953x_BANK_CONFIG;
}
if (chip->driver_data & PCA_PCAL) {
bank |= PCAL9xxx_BANK_IN_LATCH | PCAL9xxx_BANK_PULL_EN |
PCAL9xxx_BANK_PULL_SEL | PCAL9xxx_BANK_IRQ_MASK |
PCAL9xxx_BANK_IRQ_STAT;
}
return chip->check_reg(chip, reg, bank);
}
static bool pca953x_writeable_register(struct device *dev, unsigned int reg)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
u32 bank;
if (PCA_CHIP_TYPE(chip->driver_data) == PCA957X_TYPE) {
bank = PCA957x_BANK_OUTPUT | PCA957x_BANK_POLARITY |
PCA957x_BANK_CONFIG | PCA957x_BANK_BUSHOLD;
} else {
bank = PCA953x_BANK_OUTPUT | PCA953x_BANK_POLARITY |
PCA953x_BANK_CONFIG;
}
if (chip->driver_data & PCA_PCAL)
bank |= PCAL9xxx_BANK_IN_LATCH | PCAL9xxx_BANK_PULL_EN |
PCAL9xxx_BANK_PULL_SEL | PCAL9xxx_BANK_IRQ_MASK;
return chip->check_reg(chip, reg, bank);
}
static bool pca953x_volatile_register(struct device *dev, unsigned int reg)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
u32 bank;
if (PCA_CHIP_TYPE(chip->driver_data) == PCA957X_TYPE)
bank = PCA957x_BANK_INPUT;
else
bank = PCA953x_BANK_INPUT;
if (chip->driver_data & PCA_PCAL)
bank |= PCAL9xxx_BANK_IRQ_STAT;
return chip->check_reg(chip, reg, bank);
}
static const struct regmap_config pca953x_i2c_regmap = {
.reg_bits = 8,
.val_bits = 8,
.use_single_read = true,
.use_single_write = true,
.readable_reg = pca953x_readable_register,
.writeable_reg = pca953x_writeable_register,
.volatile_reg = pca953x_volatile_register,
.disable_locking = true,
.cache_type = REGCACHE_RBTREE,
.max_register = 0x7f,
};
static const struct regmap_config pca953x_ai_i2c_regmap = {
.reg_bits = 8,
.val_bits = 8,
.read_flag_mask = REG_ADDR_AI,
.write_flag_mask = REG_ADDR_AI,
.readable_reg = pca953x_readable_register,
.writeable_reg = pca953x_writeable_register,
.volatile_reg = pca953x_volatile_register,
.disable_locking = true,
.cache_type = REGCACHE_RBTREE,
.max_register = 0x7f,
};
static u8 pca953x_recalc_addr(struct pca953x_chip *chip, int reg, int off)
{
int bank_shift = pca953x_bank_shift(chip);
int addr = (reg & PCAL_GPIO_MASK) << bank_shift;
int pinctrl = (reg & PCAL_PINCTRL_MASK) << 1;
u8 regaddr = pinctrl | addr | (off / BANK_SZ);
return regaddr;
}
/*
* The PCAL6534 and compatible chips have altered bank alignment that doesn't
* fit within the bit shifting scheme used for other devices.
*/
static u8 pcal6534_recalc_addr(struct pca953x_chip *chip, int reg, int off)
{
int addr;
int pinctrl;
addr = (reg & PCAL_GPIO_MASK) * NBANK(chip);
switch (reg) {
case PCAL953X_OUT_STRENGTH:
case PCAL953X_IN_LATCH:
case PCAL953X_PULL_EN:
case PCAL953X_PULL_SEL:
case PCAL953X_INT_MASK:
case PCAL953X_INT_STAT:
case PCAL953X_OUT_CONF:
pinctrl = ((reg & PCAL_PINCTRL_MASK) >> 1) + 0x20;
break;
case PCAL6524_INT_EDGE:
case PCAL6524_INT_CLR:
case PCAL6524_IN_STATUS:
case PCAL6524_OUT_INDCONF:
case PCAL6524_DEBOUNCE:
pinctrl = ((reg & PCAL_PINCTRL_MASK) >> 1) + 0x1c;
break;
default:
pinctrl = 0;
break;
}
return pinctrl + addr + (off / BANK_SZ);
}
static int pca953x_write_regs(struct pca953x_chip *chip, int reg, unsigned long *val)
{
u8 regaddr = chip->recalc_addr(chip, reg, 0);
u8 value[MAX_BANK];
int i, ret;
for (i = 0; i < NBANK(chip); i++)
value[i] = bitmap_get_value8(val, i * BANK_SZ);
ret = regmap_bulk_write(chip->regmap, regaddr, value, NBANK(chip));
if (ret < 0) {
dev_err(&chip->client->dev, "failed writing register\n");
return ret;
}
return 0;
}
static int pca953x_read_regs(struct pca953x_chip *chip, int reg, unsigned long *val)
{
u8 regaddr = chip->recalc_addr(chip, reg, 0);
u8 value[MAX_BANK];
int i, ret;
ret = regmap_bulk_read(chip->regmap, regaddr, value, NBANK(chip));
if (ret < 0) {
dev_err(&chip->client->dev, "failed reading register\n");
return ret;
}
for (i = 0; i < NBANK(chip); i++)
bitmap_set_value8(val, value[i], i * BANK_SZ);
return 0;
}
static int pca953x_gpio_direction_input(struct gpio_chip *gc, unsigned off)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 dirreg = chip->recalc_addr(chip, chip->regs->direction, off);
u8 bit = BIT(off % BANK_SZ);
int ret;
mutex_lock(&chip->i2c_lock);
ret = regmap_write_bits(chip->regmap, dirreg, bit, bit);
mutex_unlock(&chip->i2c_lock);
return ret;
}
static int pca953x_gpio_direction_output(struct gpio_chip *gc,
unsigned off, int val)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 dirreg = chip->recalc_addr(chip, chip->regs->direction, off);
u8 outreg = chip->recalc_addr(chip, chip->regs->output, off);
u8 bit = BIT(off % BANK_SZ);
int ret;
mutex_lock(&chip->i2c_lock);
/* set output level */
ret = regmap_write_bits(chip->regmap, outreg, bit, val ? bit : 0);
if (ret)
goto exit;
/* then direction */
ret = regmap_write_bits(chip->regmap, dirreg, bit, 0);
exit:
mutex_unlock(&chip->i2c_lock);
return ret;
}
static int pca953x_gpio_get_value(struct gpio_chip *gc, unsigned off)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 inreg = chip->recalc_addr(chip, chip->regs->input, off);
u8 bit = BIT(off % BANK_SZ);
u32 reg_val;
int ret;
mutex_lock(&chip->i2c_lock);
ret = regmap_read(chip->regmap, inreg, ®_val);
mutex_unlock(&chip->i2c_lock);
if (ret < 0)
return ret;
return !!(reg_val & bit);
}
static void pca953x_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 outreg = chip->recalc_addr(chip, chip->regs->output, off);
u8 bit = BIT(off % BANK_SZ);
mutex_lock(&chip->i2c_lock);
regmap_write_bits(chip->regmap, outreg, bit, val ? bit : 0);
mutex_unlock(&chip->i2c_lock);
}
static int pca953x_gpio_get_direction(struct gpio_chip *gc, unsigned off)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
u8 dirreg = chip->recalc_addr(chip, chip->regs->direction, off);
u8 bit = BIT(off % BANK_SZ);
u32 reg_val;
int ret;
mutex_lock(&chip->i2c_lock);
ret = regmap_read(chip->regmap, dirreg, ®_val);
mutex_unlock(&chip->i2c_lock);
if (ret < 0)
return ret;
if (reg_val & bit)
return GPIO_LINE_DIRECTION_IN;
return GPIO_LINE_DIRECTION_OUT;
}
static int pca953x_gpio_get_multiple(struct gpio_chip *gc,
unsigned long *mask, unsigned long *bits)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
DECLARE_BITMAP(reg_val, MAX_LINE);
int ret;
mutex_lock(&chip->i2c_lock);
ret = pca953x_read_regs(chip, chip->regs->input, reg_val);
mutex_unlock(&chip->i2c_lock);
if (ret)
return ret;
bitmap_replace(bits, bits, reg_val, mask, gc->ngpio);
return 0;
}
static void pca953x_gpio_set_multiple(struct gpio_chip *gc,
unsigned long *mask, unsigned long *bits)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
DECLARE_BITMAP(reg_val, MAX_LINE);
int ret;
mutex_lock(&chip->i2c_lock);
ret = pca953x_read_regs(chip, chip->regs->output, reg_val);
if (ret)
goto exit;
bitmap_replace(reg_val, reg_val, bits, mask, gc->ngpio);
pca953x_write_regs(chip, chip->regs->output, reg_val);
exit:
mutex_unlock(&chip->i2c_lock);
}
static int pca953x_gpio_set_pull_up_down(struct pca953x_chip *chip,
unsigned int offset,
unsigned long config)
{
enum pin_config_param param = pinconf_to_config_param(config);
u8 pull_en_reg = chip->recalc_addr(chip, PCAL953X_PULL_EN, offset);
u8 pull_sel_reg = chip->recalc_addr(chip, PCAL953X_PULL_SEL, offset);
u8 bit = BIT(offset % BANK_SZ);
int ret;
/*
* pull-up/pull-down configuration requires PCAL extended
* registers
*/
if (!(chip->driver_data & PCA_PCAL))
return -ENOTSUPP;
mutex_lock(&chip->i2c_lock);
/* Configure pull-up/pull-down */
if (param == PIN_CONFIG_BIAS_PULL_UP)
ret = regmap_write_bits(chip->regmap, pull_sel_reg, bit, bit);
else if (param == PIN_CONFIG_BIAS_PULL_DOWN)
ret = regmap_write_bits(chip->regmap, pull_sel_reg, bit, 0);
else
ret = 0;
if (ret)
goto exit;
/* Disable/Enable pull-up/pull-down */
if (param == PIN_CONFIG_BIAS_DISABLE)
ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, 0);
else
ret = regmap_write_bits(chip->regmap, pull_en_reg, bit, bit);
exit:
mutex_unlock(&chip->i2c_lock);
return ret;
}
static int pca953x_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
unsigned long config)
{
struct pca953x_chip *chip = gpiochip_get_data(gc);
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_BIAS_PULL_UP:
case PIN_CONFIG_BIAS_PULL_PIN_DEFAULT:
case PIN_CONFIG_BIAS_PULL_DOWN:
case PIN_CONFIG_BIAS_DISABLE:
return pca953x_gpio_set_pull_up_down(chip, offset, config);
default:
return -ENOTSUPP;
}
}
static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
{
struct gpio_chip *gc;
gc = &chip->gpio_chip;
gc->direction_input = pca953x_gpio_direction_input;
gc->direction_output = pca953x_gpio_direction_output;
gc->get = pca953x_gpio_get_value;
gc->set = pca953x_gpio_set_value;
gc->get_direction = pca953x_gpio_get_direction;
gc->get_multiple = pca953x_gpio_get_multiple;
gc->set_multiple = pca953x_gpio_set_multiple;
gc->set_config = pca953x_gpio_set_config;
gc->can_sleep = true;
gc->base = chip->gpio_start;
gc->ngpio = gpios;
gc->label = dev_name(&chip->client->dev);
gc->parent = &chip->client->dev;
gc->owner = THIS_MODULE;
gc->names = chip->names;
}
#ifdef CONFIG_GPIO_PCA953X_IRQ
static void pca953x_irq_mask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
irq_hw_number_t hwirq = irqd_to_hwirq(d);
clear_bit(hwirq, chip->irq_mask);
gpiochip_disable_irq(gc, hwirq);
}
static void pca953x_irq_unmask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
irq_hw_number_t hwirq = irqd_to_hwirq(d);
gpiochip_enable_irq(gc, hwirq);
set_bit(hwirq, chip->irq_mask);
}
static int pca953x_irq_set_wake(struct irq_data *d, unsigned int on)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
if (on)
atomic_inc(&chip->wakeup_path);
else
atomic_dec(&chip->wakeup_path);
return irq_set_irq_wake(chip->client->irq, on);
}
static void pca953x_irq_bus_lock(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
mutex_lock(&chip->irq_lock);
}
static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
DECLARE_BITMAP(irq_mask, MAX_LINE);
DECLARE_BITMAP(reg_direction, MAX_LINE);
int level;
if (chip->driver_data & PCA_PCAL) {
/* Enable latch on interrupt-enabled inputs */
pca953x_write_regs(chip, PCAL953X_IN_LATCH, chip->irq_mask);
bitmap_complement(irq_mask, chip->irq_mask, gc->ngpio);
/* Unmask enabled interrupts */
pca953x_write_regs(chip, PCAL953X_INT_MASK, irq_mask);
}
/* Switch direction to input if needed */
pca953x_read_regs(chip, chip->regs->direction, reg_direction);
bitmap_or(irq_mask, chip->irq_trig_fall, chip->irq_trig_raise, gc->ngpio);
bitmap_complement(reg_direction, reg_direction, gc->ngpio);
bitmap_and(irq_mask, irq_mask, reg_direction, gc->ngpio);
/* Look for any newly setup interrupt */
for_each_set_bit(level, irq_mask, gc->ngpio)
pca953x_gpio_direction_input(&chip->gpio_chip, level);
mutex_unlock(&chip->irq_lock);
}
static int pca953x_irq_set_type(struct irq_data *d, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
irq_hw_number_t hwirq = irqd_to_hwirq(d);
if (!(type & IRQ_TYPE_EDGE_BOTH)) {
dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
d->irq, type);
return -EINVAL;
}
assign_bit(hwirq, chip->irq_trig_fall, type & IRQ_TYPE_EDGE_FALLING);
assign_bit(hwirq, chip->irq_trig_raise, type & IRQ_TYPE_EDGE_RISING);
return 0;
}
static void pca953x_irq_shutdown(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct pca953x_chip *chip = gpiochip_get_data(gc);
irq_hw_number_t hwirq = irqd_to_hwirq(d);
clear_bit(hwirq, chip->irq_trig_raise);
clear_bit(hwirq, chip->irq_trig_fall);
}
static void pca953x_irq_print_chip(struct irq_data *data, struct seq_file *p)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
seq_printf(p, dev_name(gc->parent));
}
static const struct irq_chip pca953x_irq_chip = {
.irq_mask = pca953x_irq_mask,
.irq_unmask = pca953x_irq_unmask,
.irq_set_wake = pca953x_irq_set_wake,
.irq_bus_lock = pca953x_irq_bus_lock,
.irq_bus_sync_unlock = pca953x_irq_bus_sync_unlock,
.irq_set_type = pca953x_irq_set_type,
.irq_shutdown = pca953x_irq_shutdown,
.irq_print_chip = pca953x_irq_print_chip,
.flags = IRQCHIP_IMMUTABLE,
GPIOCHIP_IRQ_RESOURCE_HELPERS,
};
static bool pca953x_irq_pending(struct pca953x_chip *chip, unsigned long *pending)
{
struct gpio_chip *gc = &chip->gpio_chip;
DECLARE_BITMAP(reg_direction, MAX_LINE);
DECLARE_BITMAP(old_stat, MAX_LINE);
DECLARE_BITMAP(cur_stat, MAX_LINE);
DECLARE_BITMAP(new_stat, MAX_LINE);
DECLARE_BITMAP(trigger, MAX_LINE);
int ret;
if (chip->driver_data & PCA_PCAL) {
/* Read the current interrupt status from the device */
ret = pca953x_read_regs(chip, PCAL953X_INT_STAT, trigger);
if (ret)
return false;
/* Check latched inputs and clear interrupt status */
ret = pca953x_read_regs(chip, chip->regs->input, cur_stat);
if (ret)
return false;
/* Apply filter for rising/falling edge selection */
bitmap_replace(new_stat, chip->irq_trig_fall, chip->irq_trig_raise, cur_stat, gc->ngpio);
bitmap_and(pending, new_stat, trigger, gc->ngpio);
return !bitmap_empty(pending, gc->ngpio);
}
ret = pca953x_read_regs(chip, chip->regs->input, cur_stat);
if (ret)
return false;
/* Remove output pins from the equation */
pca953x_read_regs(chip, chip->regs->direction, reg_direction);
bitmap_copy(old_stat, chip->irq_stat, gc->ngpio);
bitmap_and(new_stat, cur_stat, reg_direction, gc->ngpio);
bitmap_xor(cur_stat, new_stat, old_stat, gc->ngpio);
bitmap_and(trigger, cur_stat, chip->irq_mask, gc->ngpio);
bitmap_copy(chip->irq_stat, new_stat, gc->ngpio);
if (bitmap_empty(trigger, gc->ngpio))
return false;
bitmap_and(cur_stat, chip->irq_trig_fall, old_stat, gc->ngpio);
bitmap_and(old_stat, chip->irq_trig_raise, new_stat, gc->ngpio);
bitmap_or(new_stat, old_stat, cur_stat, gc->ngpio);
bitmap_and(pending, new_stat, trigger, gc->ngpio);
return !bitmap_empty(pending, gc->ngpio);
}
static irqreturn_t pca953x_irq_handler(int irq, void *devid)
{
struct pca953x_chip *chip = devid;
struct gpio_chip *gc = &chip->gpio_chip;
DECLARE_BITMAP(pending, MAX_LINE);
int level;
bool ret;
bitmap_zero(pending, MAX_LINE);
mutex_lock(&chip->i2c_lock);
ret = pca953x_irq_pending(chip, pending);
mutex_unlock(&chip->i2c_lock);
if (ret) {
ret = 0;
for_each_set_bit(level, pending, gc->ngpio) {
int nested_irq = irq_find_mapping(gc->irq.domain, level);
if (unlikely(nested_irq <= 0)) {
dev_warn_ratelimited(gc->parent, "unmapped interrupt %d\n", level);
continue;
}
handle_nested_irq(nested_irq);
ret = 1;
}
}
return IRQ_RETVAL(ret);
}
static int pca953x_irq_setup(struct pca953x_chip *chip, int irq_base)
{
struct i2c_client *client = chip->client;
DECLARE_BITMAP(reg_direction, MAX_LINE);
DECLARE_BITMAP(irq_stat, MAX_LINE);
struct gpio_irq_chip *girq;
int ret;
if (dmi_first_match(pca953x_dmi_acpi_irq_info)) {
ret = pca953x_acpi_get_irq(&client->dev);
if (ret > 0)
client->irq = ret;
}
if (!client->irq)
return 0;
if (irq_base == -1)
return 0;
if (!(chip->driver_data & PCA_INT))
return 0;
ret = pca953x_read_regs(chip, chip->regs->input, irq_stat);
if (ret)
return ret;
/*
* There is no way to know which GPIO line generated the
* interrupt. We have to rely on the previous read for
* this purpose.
*/
pca953x_read_regs(chip, chip->regs->direction, reg_direction);
bitmap_and(chip->irq_stat, irq_stat, reg_direction, chip->gpio_chip.ngpio);
mutex_init(&chip->irq_lock);
girq = &chip->gpio_chip.irq;
gpio_irq_chip_set_chip(girq, &pca953x_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 */
ret = devm_request_threaded_irq(&client->dev, client->irq,
NULL, pca953x_irq_handler,
IRQF_ONESHOT | IRQF_SHARED,
dev_name(&client->dev), chip);
if (ret) {
dev_err(&client->dev, "failed to request irq %d\n",
client->irq);
return ret;
}
return 0;
}
#else /* CONFIG_GPIO_PCA953X_IRQ */
static int pca953x_irq_setup(struct pca953x_chip *chip,
int irq_base)
{
struct i2c_client *client = chip->client;
if (client->irq && irq_base != -1 && (chip->driver_data & PCA_INT))
dev_warn(&client->dev, "interrupt support not compiled in\n");
return 0;
}
#endif
static int device_pca95xx_init(struct pca953x_chip *chip, u32 invert)
{
DECLARE_BITMAP(val, MAX_LINE);
u8 regaddr;
int ret;
regaddr = chip->recalc_addr(chip, chip->regs->output, 0);
ret = regcache_sync_region(chip->regmap, regaddr,
regaddr + NBANK(chip) - 1);
if (ret)
goto out;
regaddr = chip->recalc_addr(chip, chip->regs->direction, 0);
ret = regcache_sync_region(chip->regmap, regaddr,
regaddr + NBANK(chip) - 1);
if (ret)
goto out;
/* set platform specific polarity inversion */
if (invert)
bitmap_fill(val, MAX_LINE);
else
bitmap_zero(val, MAX_LINE);
ret = pca953x_write_regs(chip, chip->regs->invert, val);
out:
return ret;
}
static int device_pca957x_init(struct pca953x_chip *chip, u32 invert)
{
DECLARE_BITMAP(val, MAX_LINE);
unsigned int i;
int ret;
ret = device_pca95xx_init(chip, invert);
if (ret)
goto out;
/* To enable register 6, 7 to control pull up and pull down */
for (i = 0; i < NBANK(chip); i++)
bitmap_set_value8(val, 0x02, i * BANK_SZ);
ret = pca953x_write_regs(chip, PCA957X_BKEN, val);
if (ret)
goto out;
return 0;
out:
return ret;
}
static int pca953x_probe(struct i2c_client *client,
const struct i2c_device_id *i2c_id)
{
struct pca953x_platform_data *pdata;
struct pca953x_chip *chip;
int irq_base = 0;
int ret;
u32 invert = 0;
struct regulator *reg;
const struct regmap_config *regmap_config;
chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
if (chip == NULL)
return -ENOMEM;
pdata = dev_get_platdata(&client->dev);
if (pdata) {
irq_base = pdata->irq_base;
chip->gpio_start = pdata->gpio_base;
invert = pdata->invert;
chip->names = pdata->names;
} else {
struct gpio_desc *reset_gpio;
chip->gpio_start = -1;
irq_base = 0;
/*
* See if we need to de-assert a reset pin.
*
* There is no known ACPI-enabled platforms that are
* using "reset" GPIO. Otherwise any of those platform
* must use _DSD method with corresponding property.
*/
reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
GPIOD_OUT_LOW);
if (IS_ERR(reset_gpio))
return PTR_ERR(reset_gpio);
}
chip->client = client;
reg = devm_regulator_get(&client->dev, "vcc");
if (IS_ERR(reg))
return dev_err_probe(&client->dev, PTR_ERR(reg), "reg get err\n");
ret = regulator_enable(reg);
if (ret) {
dev_err(&client->dev, "reg en err: %d\n", ret);
return ret;
}
chip->regulator = reg;
if (i2c_id) {
chip->driver_data = i2c_id->driver_data;
} else {
const void *match;
match = device_get_match_data(&client->dev);
if (!match) {
ret = -ENODEV;
goto err_exit;
}
chip->driver_data = (uintptr_t)match;
}
i2c_set_clientdata(client, chip);
pca953x_setup_gpio(chip, chip->driver_data & PCA_GPIO_MASK);
if (NBANK(chip) > 2 || PCA_CHIP_TYPE(chip->driver_data) == PCA957X_TYPE) {
dev_info(&client->dev, "using AI\n");
regmap_config = &pca953x_ai_i2c_regmap;
} else {
dev_info(&client->dev, "using no AI\n");
regmap_config = &pca953x_i2c_regmap;
}
if (PCA_CHIP_TYPE(chip->driver_data) == PCAL653X_TYPE) {
chip->recalc_addr = pcal6534_recalc_addr;
chip->check_reg = pcal6534_check_register;
} else {
chip->recalc_addr = pca953x_recalc_addr;
chip->check_reg = pca953x_check_register;
}
chip->regmap = devm_regmap_init_i2c(client, regmap_config);
if (IS_ERR(chip->regmap)) {
ret = PTR_ERR(chip->regmap);
goto err_exit;
}
regcache_mark_dirty(chip->regmap);
mutex_init(&chip->i2c_lock);
/*
* In case we have an i2c-mux controlled by a GPIO provided by an
* expander using the same driver higher on the device tree, read the
* i2c adapter nesting depth and use the retrieved value as lockdep
* subclass for chip->i2c_lock.
*
* REVISIT: This solution is not complete. It protects us from lockdep
* false positives when the expander controlling the i2c-mux is on
* a different level on the device tree, but not when it's on the same
* level on a different branch (in which case the subclass number
* would be the same).
*
* TODO: Once a correct solution is developed, a similar fix should be
* applied to all other i2c-controlled GPIO expanders (and potentially
* regmap-i2c).
*/
lockdep_set_subclass(&chip->i2c_lock,
i2c_adapter_depth(client->adapter));
/* initialize cached registers from their original values.
* we can't share this chip with another i2c master.
*/
if (PCA_CHIP_TYPE(chip->driver_data) == PCA957X_TYPE) {
chip->regs = &pca957x_regs;
ret = device_pca957x_init(chip, invert);
} else {
chip->regs = &pca953x_regs;
ret = device_pca95xx_init(chip, invert);
}
if (ret)
goto err_exit;
ret = pca953x_irq_setup(chip, irq_base);
if (ret)
goto err_exit;
ret = devm_gpiochip_add_data(&client->dev, &chip->gpio_chip, chip);
if (ret)
goto err_exit;
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);
}
return 0;
err_exit:
regulator_disable(chip->regulator);
return ret;
}
static void pca953x_remove(struct i2c_client *client)
{
struct pca953x_platform_data *pdata = dev_get_platdata(&client->dev);
struct pca953x_chip *chip = i2c_get_clientdata(client);
if (pdata && pdata->teardown) {
pdata->teardown(client, chip->gpio_chip.base,
chip->gpio_chip.ngpio, pdata->context);
}
regulator_disable(chip->regulator);
}
#ifdef CONFIG_PM_SLEEP
static int pca953x_regcache_sync(struct device *dev)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
int ret;
u8 regaddr;
/*
* The ordering between direction and output is important,
* sync these registers first and only then sync the rest.
*/
regaddr = chip->recalc_addr(chip, chip->regs->direction, 0);
ret = regcache_sync_region(chip->regmap, regaddr, regaddr + NBANK(chip) - 1);
if (ret) {
dev_err(dev, "Failed to sync GPIO dir registers: %d\n", ret);
return ret;
}
regaddr = chip->recalc_addr(chip, chip->regs->output, 0);
ret = regcache_sync_region(chip->regmap, regaddr, regaddr + NBANK(chip) - 1);
if (ret) {
dev_err(dev, "Failed to sync GPIO out registers: %d\n", ret);
return ret;
}
#ifdef CONFIG_GPIO_PCA953X_IRQ
if (chip->driver_data & PCA_PCAL) {
regaddr = chip->recalc_addr(chip, PCAL953X_IN_LATCH, 0);
ret = regcache_sync_region(chip->regmap, regaddr,
regaddr + NBANK(chip) - 1);
if (ret) {
dev_err(dev, "Failed to sync INT latch registers: %d\n",
ret);
return ret;
}
regaddr = chip->recalc_addr(chip, PCAL953X_INT_MASK, 0);
ret = regcache_sync_region(chip->regmap, regaddr,
regaddr + NBANK(chip) - 1);
if (ret) {
dev_err(dev, "Failed to sync INT mask registers: %d\n",
ret);
return ret;
}
}
#endif
return 0;
}
static int pca953x_suspend(struct device *dev)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
mutex_lock(&chip->i2c_lock);
regcache_cache_only(chip->regmap, true);
mutex_unlock(&chip->i2c_lock);
if (atomic_read(&chip->wakeup_path))
device_set_wakeup_path(dev);
else
regulator_disable(chip->regulator);
return 0;
}
static int pca953x_resume(struct device *dev)
{
struct pca953x_chip *chip = dev_get_drvdata(dev);
int ret;
if (!atomic_read(&chip->wakeup_path)) {
ret = regulator_enable(chip->regulator);
if (ret) {
dev_err(dev, "Failed to enable regulator: %d\n", ret);
return 0;
}
}
mutex_lock(&chip->i2c_lock);
regcache_cache_only(chip->regmap, false);
regcache_mark_dirty(chip->regmap);
ret = pca953x_regcache_sync(dev);
if (ret) {
mutex_unlock(&chip->i2c_lock);
return ret;
}
ret = regcache_sync(chip->regmap);
mutex_unlock(&chip->i2c_lock);
if (ret) {
dev_err(dev, "Failed to restore register map: %d\n", ret);
return ret;
}
return 0;
}
#endif
/* convenience to stop overlong match-table lines */
#define OF_653X(__nrgpio, __int) ((void *)(__nrgpio | PCAL653X_TYPE | __int))
#define OF_953X(__nrgpio, __int) (void *)(__nrgpio | PCA953X_TYPE | __int)
#define OF_957X(__nrgpio, __int) (void *)(__nrgpio | PCA957X_TYPE | __int)
static const struct of_device_id pca953x_dt_ids[] = {
{ .compatible = "nxp,pca6408", .data = OF_953X(8, PCA_INT), },
{ .compatible = "nxp,pca6416", .data = OF_953X(16, PCA_INT), },
{ .compatible = "nxp,pca9505", .data = OF_953X(40, PCA_INT), },
{ .compatible = "nxp,pca9506", .data = OF_953X(40, PCA_INT), },
{ .compatible = "nxp,pca9534", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "nxp,pca9535", .data = OF_953X(16, PCA_INT), },
{ .compatible = "nxp,pca9536", .data = OF_953X( 4, 0), },
{ .compatible = "nxp,pca9537", .data = OF_953X( 4, PCA_INT), },
{ .compatible = "nxp,pca9538", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "nxp,pca9539", .data = OF_953X(16, PCA_INT), },
{ .compatible = "nxp,pca9554", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "nxp,pca9555", .data = OF_953X(16, PCA_INT), },
{ .compatible = "nxp,pca9556", .data = OF_953X( 8, 0), },
{ .compatible = "nxp,pca9557", .data = OF_953X( 8, 0), },
{ .compatible = "nxp,pca9574", .data = OF_957X( 8, PCA_INT), },
{ .compatible = "nxp,pca9575", .data = OF_957X(16, PCA_INT), },
{ .compatible = "nxp,pca9698", .data = OF_953X(40, 0), },
{ .compatible = "nxp,pcal6408", .data = OF_953X(8, PCA_LATCH_INT), },
{ .compatible = "nxp,pcal6416", .data = OF_953X(16, PCA_LATCH_INT), },
{ .compatible = "nxp,pcal6524", .data = OF_953X(24, PCA_LATCH_INT), },
{ .compatible = "nxp,pcal6534", .data = OF_653X(34, PCA_LATCH_INT), },
{ .compatible = "nxp,pcal9535", .data = OF_953X(16, PCA_LATCH_INT), },
{ .compatible = "nxp,pcal9554b", .data = OF_953X( 8, PCA_LATCH_INT), },
{ .compatible = "nxp,pcal9555a", .data = OF_953X(16, PCA_LATCH_INT), },
{ .compatible = "maxim,max7310", .data = OF_953X( 8, 0), },
{ .compatible = "maxim,max7312", .data = OF_953X(16, PCA_INT), },
{ .compatible = "maxim,max7313", .data = OF_953X(16, PCA_INT), },
{ .compatible = "maxim,max7315", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "maxim,max7318", .data = OF_953X(16, PCA_INT), },
{ .compatible = "ti,pca6107", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "ti,pca9536", .data = OF_953X( 4, 0), },
{ .compatible = "ti,tca6408", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "ti,tca6416", .data = OF_953X(16, PCA_INT), },
{ .compatible = "ti,tca6424", .data = OF_953X(24, PCA_INT), },
{ .compatible = "ti,tca9539", .data = OF_953X(16, PCA_INT), },
{ .compatible = "onnn,cat9554", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "onnn,pca9654", .data = OF_953X( 8, PCA_INT), },
{ .compatible = "onnn,pca9655", .data = OF_953X(16, PCA_INT), },
{ .compatible = "exar,xra1202", .data = OF_953X( 8, 0), },
{ }
};
MODULE_DEVICE_TABLE(of, pca953x_dt_ids);
static SIMPLE_DEV_PM_OPS(pca953x_pm_ops, pca953x_suspend, pca953x_resume);
static struct i2c_driver pca953x_driver = {
.driver = {
.name = "pca953x",
.pm = &pca953x_pm_ops,
.of_match_table = pca953x_dt_ids,
.acpi_match_table = pca953x_acpi_ids,
},
.probe = pca953x_probe,
.remove = pca953x_remove,
.id_table = pca953x_id,
};
static int __init pca953x_init(void)
{
return i2c_add_driver(&pca953x_driver);
}
/* register after i2c postcore initcall and before
* subsys initcalls that may rely on these GPIOs
*/
subsys_initcall(pca953x_init);
static void __exit pca953x_exit(void)
{
i2c_del_driver(&pca953x_driver);
}
module_exit(pca953x_exit);
MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
MODULE_DESCRIPTION("GPIO expander driver for PCA953x");
MODULE_LICENSE("GPL");
