linux/drivers/pinctrl/pinctrl-mcp23s08.c
Andy Shevchenko 8a8d6bbe1d pinctrl: Get rid of duplicate of_node assignment in the drivers
GPIO library does copy the of_node from the parent device of
the GPIO chip, there is no need to repeat this in the individual
drivers. Remove these assignment all at once.

For the details one may look into the of_gpio_dev_init() implementation.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20211214125855.33207-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2021-12-16 04:18:30 +01:00

647 lines
17 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* MCP23S08 SPI/I2C GPIO driver */
#include <linux/bitops.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/mutex.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/export.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/consumer.h>
#include <linux/slab.h>
#include <asm/byteorder.h>
#include <linux/interrupt.h>
#include <linux/regmap.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
#include "pinctrl-mcp23s08.h"
/* Registers are all 8 bits wide.
*
* The mcp23s17 has twice as many bits, and can be configured to work
* with either 16 bit registers or with two adjacent 8 bit banks.
*/
#define MCP_IODIR 0x00 /* init/reset: all ones */
#define MCP_IPOL 0x01
#define MCP_GPINTEN 0x02
#define MCP_DEFVAL 0x03
#define MCP_INTCON 0x04
#define MCP_IOCON 0x05
# define IOCON_MIRROR (1 << 6)
# define IOCON_SEQOP (1 << 5)
# define IOCON_HAEN (1 << 3)
# define IOCON_ODR (1 << 2)
# define IOCON_INTPOL (1 << 1)
# define IOCON_INTCC (1)
#define MCP_GPPU 0x06
#define MCP_INTF 0x07
#define MCP_INTCAP 0x08
#define MCP_GPIO 0x09
#define MCP_OLAT 0x0a
static const struct reg_default mcp23x08_defaults[] = {
{.reg = MCP_IODIR, .def = 0xff},
{.reg = MCP_IPOL, .def = 0x00},
{.reg = MCP_GPINTEN, .def = 0x00},
{.reg = MCP_DEFVAL, .def = 0x00},
{.reg = MCP_INTCON, .def = 0x00},
{.reg = MCP_IOCON, .def = 0x00},
{.reg = MCP_GPPU, .def = 0x00},
{.reg = MCP_OLAT, .def = 0x00},
};
static const struct regmap_range mcp23x08_volatile_range = {
.range_min = MCP_INTF,
.range_max = MCP_GPIO,
};
static const struct regmap_access_table mcp23x08_volatile_table = {
.yes_ranges = &mcp23x08_volatile_range,
.n_yes_ranges = 1,
};
static const struct regmap_range mcp23x08_precious_range = {
.range_min = MCP_GPIO,
.range_max = MCP_GPIO,
};
static const struct regmap_access_table mcp23x08_precious_table = {
.yes_ranges = &mcp23x08_precious_range,
.n_yes_ranges = 1,
};
const struct regmap_config mcp23x08_regmap = {
.reg_bits = 8,
.val_bits = 8,
.reg_stride = 1,
.volatile_table = &mcp23x08_volatile_table,
.precious_table = &mcp23x08_precious_table,
.reg_defaults = mcp23x08_defaults,
.num_reg_defaults = ARRAY_SIZE(mcp23x08_defaults),
.cache_type = REGCACHE_FLAT,
.max_register = MCP_OLAT,
};
EXPORT_SYMBOL_GPL(mcp23x08_regmap);
static const struct reg_default mcp23x17_defaults[] = {
{.reg = MCP_IODIR << 1, .def = 0xffff},
{.reg = MCP_IPOL << 1, .def = 0x0000},
{.reg = MCP_GPINTEN << 1, .def = 0x0000},
{.reg = MCP_DEFVAL << 1, .def = 0x0000},
{.reg = MCP_INTCON << 1, .def = 0x0000},
{.reg = MCP_IOCON << 1, .def = 0x0000},
{.reg = MCP_GPPU << 1, .def = 0x0000},
{.reg = MCP_OLAT << 1, .def = 0x0000},
};
static const struct regmap_range mcp23x17_volatile_range = {
.range_min = MCP_INTF << 1,
.range_max = MCP_GPIO << 1,
};
static const struct regmap_access_table mcp23x17_volatile_table = {
.yes_ranges = &mcp23x17_volatile_range,
.n_yes_ranges = 1,
};
static const struct regmap_range mcp23x17_precious_range = {
.range_min = MCP_INTCAP << 1,
.range_max = MCP_GPIO << 1,
};
static const struct regmap_access_table mcp23x17_precious_table = {
.yes_ranges = &mcp23x17_precious_range,
.n_yes_ranges = 1,
};
const struct regmap_config mcp23x17_regmap = {
.reg_bits = 8,
.val_bits = 16,
.reg_stride = 2,
.max_register = MCP_OLAT << 1,
.volatile_table = &mcp23x17_volatile_table,
.precious_table = &mcp23x17_precious_table,
.reg_defaults = mcp23x17_defaults,
.num_reg_defaults = ARRAY_SIZE(mcp23x17_defaults),
.cache_type = REGCACHE_FLAT,
.val_format_endian = REGMAP_ENDIAN_LITTLE,
};
EXPORT_SYMBOL_GPL(mcp23x17_regmap);
static int mcp_read(struct mcp23s08 *mcp, unsigned int reg, unsigned int *val)
{
return regmap_read(mcp->regmap, reg << mcp->reg_shift, val);
}
static int mcp_write(struct mcp23s08 *mcp, unsigned int reg, unsigned int val)
{
return regmap_write(mcp->regmap, reg << mcp->reg_shift, val);
}
static int mcp_set_mask(struct mcp23s08 *mcp, unsigned int reg,
unsigned int mask, bool enabled)
{
u16 val = enabled ? 0xffff : 0x0000;
return regmap_update_bits(mcp->regmap, reg << mcp->reg_shift,
mask, val);
}
static int mcp_set_bit(struct mcp23s08 *mcp, unsigned int reg,
unsigned int pin, bool enabled)
{
u16 mask = BIT(pin);
return mcp_set_mask(mcp, reg, mask, enabled);
}
static const struct pinctrl_pin_desc mcp23x08_pins[] = {
PINCTRL_PIN(0, "gpio0"),
PINCTRL_PIN(1, "gpio1"),
PINCTRL_PIN(2, "gpio2"),
PINCTRL_PIN(3, "gpio3"),
PINCTRL_PIN(4, "gpio4"),
PINCTRL_PIN(5, "gpio5"),
PINCTRL_PIN(6, "gpio6"),
PINCTRL_PIN(7, "gpio7"),
};
static const struct pinctrl_pin_desc mcp23x17_pins[] = {
PINCTRL_PIN(0, "gpio0"),
PINCTRL_PIN(1, "gpio1"),
PINCTRL_PIN(2, "gpio2"),
PINCTRL_PIN(3, "gpio3"),
PINCTRL_PIN(4, "gpio4"),
PINCTRL_PIN(5, "gpio5"),
PINCTRL_PIN(6, "gpio6"),
PINCTRL_PIN(7, "gpio7"),
PINCTRL_PIN(8, "gpio8"),
PINCTRL_PIN(9, "gpio9"),
PINCTRL_PIN(10, "gpio10"),
PINCTRL_PIN(11, "gpio11"),
PINCTRL_PIN(12, "gpio12"),
PINCTRL_PIN(13, "gpio13"),
PINCTRL_PIN(14, "gpio14"),
PINCTRL_PIN(15, "gpio15"),
};
static int mcp_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
{
return 0;
}
static const char *mcp_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
unsigned int group)
{
return NULL;
}
static int mcp_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
unsigned int group,
const unsigned int **pins,
unsigned int *num_pins)
{
return -ENOTSUPP;
}
static const struct pinctrl_ops mcp_pinctrl_ops = {
.get_groups_count = mcp_pinctrl_get_groups_count,
.get_group_name = mcp_pinctrl_get_group_name,
.get_group_pins = mcp_pinctrl_get_group_pins,
#ifdef CONFIG_OF
.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
.dt_free_map = pinconf_generic_dt_free_map,
#endif
};
static int mcp_pinconf_get(struct pinctrl_dev *pctldev, unsigned int pin,
unsigned long *config)
{
struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
enum pin_config_param param = pinconf_to_config_param(*config);
unsigned int data, status;
int ret;
switch (param) {
case PIN_CONFIG_BIAS_PULL_UP:
ret = mcp_read(mcp, MCP_GPPU, &data);
if (ret < 0)
return ret;
status = (data & BIT(pin)) ? 1 : 0;
break;
default:
return -ENOTSUPP;
}
*config = 0;
return status ? 0 : -EINVAL;
}
static int mcp_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
unsigned long *configs, unsigned int num_configs)
{
struct mcp23s08 *mcp = pinctrl_dev_get_drvdata(pctldev);
enum pin_config_param param;
u32 arg;
int ret = 0;
int i;
for (i = 0; i < num_configs; i++) {
param = pinconf_to_config_param(configs[i]);
arg = pinconf_to_config_argument(configs[i]);
switch (param) {
case PIN_CONFIG_BIAS_PULL_UP:
ret = mcp_set_bit(mcp, MCP_GPPU, pin, arg);
break;
default:
dev_dbg(mcp->dev, "Invalid config param %04x\n", param);
return -ENOTSUPP;
}
}
return ret;
}
static const struct pinconf_ops mcp_pinconf_ops = {
.pin_config_get = mcp_pinconf_get,
.pin_config_set = mcp_pinconf_set,
.is_generic = true,
};
/*----------------------------------------------------------------------*/
static int mcp23s08_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct mcp23s08 *mcp = gpiochip_get_data(chip);
int status;
mutex_lock(&mcp->lock);
status = mcp_set_bit(mcp, MCP_IODIR, offset, true);
mutex_unlock(&mcp->lock);
return status;
}
static int mcp23s08_get(struct gpio_chip *chip, unsigned offset)
{
struct mcp23s08 *mcp = gpiochip_get_data(chip);
int status, ret;
mutex_lock(&mcp->lock);
/* REVISIT reading this clears any IRQ ... */
ret = mcp_read(mcp, MCP_GPIO, &status);
if (ret < 0)
status = 0;
else {
mcp->cached_gpio = status;
status = !!(status & (1 << offset));
}
mutex_unlock(&mcp->lock);
return status;
}
static int __mcp23s08_set(struct mcp23s08 *mcp, unsigned mask, bool value)
{
return mcp_set_mask(mcp, MCP_OLAT, mask, value);
}
static void mcp23s08_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct mcp23s08 *mcp = gpiochip_get_data(chip);
unsigned mask = BIT(offset);
mutex_lock(&mcp->lock);
__mcp23s08_set(mcp, mask, !!value);
mutex_unlock(&mcp->lock);
}
static int
mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
{
struct mcp23s08 *mcp = gpiochip_get_data(chip);
unsigned mask = BIT(offset);
int status;
mutex_lock(&mcp->lock);
status = __mcp23s08_set(mcp, mask, value);
if (status == 0) {
status = mcp_set_mask(mcp, MCP_IODIR, mask, false);
}
mutex_unlock(&mcp->lock);
return status;
}
/*----------------------------------------------------------------------*/
static irqreturn_t mcp23s08_irq(int irq, void *data)
{
struct mcp23s08 *mcp = data;
int intcap, intcon, intf, i, gpio, gpio_orig, intcap_mask, defval;
unsigned int child_irq;
bool intf_set, intcap_changed, gpio_bit_changed,
defval_changed, gpio_set;
mutex_lock(&mcp->lock);
if (mcp_read(mcp, MCP_INTF, &intf))
goto unlock;
if (intf == 0) {
/* There is no interrupt pending */
goto unlock;
}
if (mcp_read(mcp, MCP_INTCAP, &intcap))
goto unlock;
if (mcp_read(mcp, MCP_INTCON, &intcon))
goto unlock;
if (mcp_read(mcp, MCP_DEFVAL, &defval))
goto unlock;
/* This clears the interrupt(configurable on S18) */
if (mcp_read(mcp, MCP_GPIO, &gpio))
goto unlock;
gpio_orig = mcp->cached_gpio;
mcp->cached_gpio = gpio;
mutex_unlock(&mcp->lock);
dev_dbg(mcp->chip.parent,
"intcap 0x%04X intf 0x%04X gpio_orig 0x%04X gpio 0x%04X\n",
intcap, intf, gpio_orig, gpio);
for (i = 0; i < mcp->chip.ngpio; i++) {
/* We must check all of the inputs on the chip,
* otherwise we may not notice a change on >=2 pins.
*
* On at least the mcp23s17, INTCAP is only updated
* one byte at a time(INTCAPA and INTCAPB are
* not written to at the same time - only on a per-bank
* basis).
*
* INTF only contains the single bit that caused the
* interrupt per-bank. On the mcp23s17, there is
* INTFA and INTFB. If two pins are changed on the A
* side at the same time, INTF will only have one bit
* set. If one pin on the A side and one pin on the B
* side are changed at the same time, INTF will have
* two bits set. Thus, INTF can't be the only check
* to see if the input has changed.
*/
intf_set = intf & BIT(i);
if (i < 8 && intf_set)
intcap_mask = 0x00FF;
else if (i >= 8 && intf_set)
intcap_mask = 0xFF00;
else
intcap_mask = 0x00;
intcap_changed = (intcap_mask &
(intcap & BIT(i))) !=
(intcap_mask & (BIT(i) & gpio_orig));
gpio_set = BIT(i) & gpio;
gpio_bit_changed = (BIT(i) & gpio_orig) !=
(BIT(i) & gpio);
defval_changed = (BIT(i) & intcon) &&
((BIT(i) & gpio) !=
(BIT(i) & defval));
if (((gpio_bit_changed || intcap_changed) &&
(BIT(i) & mcp->irq_rise) && gpio_set) ||
((gpio_bit_changed || intcap_changed) &&
(BIT(i) & mcp->irq_fall) && !gpio_set) ||
defval_changed) {
child_irq = irq_find_mapping(mcp->chip.irq.domain, i);
handle_nested_irq(child_irq);
}
}
return IRQ_HANDLED;
unlock:
mutex_unlock(&mcp->lock);
return IRQ_HANDLED;
}
static void mcp23s08_irq_mask(struct irq_data *data)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
struct mcp23s08 *mcp = gpiochip_get_data(gc);
unsigned int pos = data->hwirq;
mcp_set_bit(mcp, MCP_GPINTEN, pos, false);
}
static void mcp23s08_irq_unmask(struct irq_data *data)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
struct mcp23s08 *mcp = gpiochip_get_data(gc);
unsigned int pos = data->hwirq;
mcp_set_bit(mcp, MCP_GPINTEN, pos, true);
}
static int mcp23s08_irq_set_type(struct irq_data *data, unsigned int type)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
struct mcp23s08 *mcp = gpiochip_get_data(gc);
unsigned int pos = data->hwirq;
if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
mcp_set_bit(mcp, MCP_INTCON, pos, false);
mcp->irq_rise |= BIT(pos);
mcp->irq_fall |= BIT(pos);
} else if (type & IRQ_TYPE_EDGE_RISING) {
mcp_set_bit(mcp, MCP_INTCON, pos, false);
mcp->irq_rise |= BIT(pos);
mcp->irq_fall &= ~BIT(pos);
} else if (type & IRQ_TYPE_EDGE_FALLING) {
mcp_set_bit(mcp, MCP_INTCON, pos, false);
mcp->irq_rise &= ~BIT(pos);
mcp->irq_fall |= BIT(pos);
} else if (type & IRQ_TYPE_LEVEL_HIGH) {
mcp_set_bit(mcp, MCP_INTCON, pos, true);
mcp_set_bit(mcp, MCP_DEFVAL, pos, false);
} else if (type & IRQ_TYPE_LEVEL_LOW) {
mcp_set_bit(mcp, MCP_INTCON, pos, true);
mcp_set_bit(mcp, MCP_DEFVAL, pos, true);
} else
return -EINVAL;
return 0;
}
static void mcp23s08_irq_bus_lock(struct irq_data *data)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
struct mcp23s08 *mcp = gpiochip_get_data(gc);
mutex_lock(&mcp->lock);
regcache_cache_only(mcp->regmap, true);
}
static void mcp23s08_irq_bus_unlock(struct irq_data *data)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
struct mcp23s08 *mcp = gpiochip_get_data(gc);
regcache_cache_only(mcp->regmap, false);
regcache_sync(mcp->regmap);
mutex_unlock(&mcp->lock);
}
static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
{
struct gpio_chip *chip = &mcp->chip;
int err;
unsigned long irqflags = IRQF_ONESHOT | IRQF_SHARED;
if (mcp->irq_active_high)
irqflags |= IRQF_TRIGGER_HIGH;
else
irqflags |= IRQF_TRIGGER_LOW;
err = devm_request_threaded_irq(chip->parent, mcp->irq, NULL,
mcp23s08_irq,
irqflags, dev_name(chip->parent), mcp);
if (err != 0) {
dev_err(chip->parent, "unable to request IRQ#%d: %d\n",
mcp->irq, err);
return err;
}
return 0;
}
/*----------------------------------------------------------------------*/
int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
unsigned int addr, unsigned int type, unsigned int base)
{
int status, ret;
bool mirror = false;
bool open_drain = false;
mutex_init(&mcp->lock);
mcp->dev = dev;
mcp->addr = addr;
mcp->irq_active_high = false;
mcp->irq_chip.name = dev_name(dev);
mcp->irq_chip.irq_mask = mcp23s08_irq_mask;
mcp->irq_chip.irq_unmask = mcp23s08_irq_unmask;
mcp->irq_chip.irq_set_type = mcp23s08_irq_set_type;
mcp->irq_chip.irq_bus_lock = mcp23s08_irq_bus_lock;
mcp->irq_chip.irq_bus_sync_unlock = mcp23s08_irq_bus_unlock;
mcp->chip.direction_input = mcp23s08_direction_input;
mcp->chip.get = mcp23s08_get;
mcp->chip.direction_output = mcp23s08_direction_output;
mcp->chip.set = mcp23s08_set;
#ifdef CONFIG_OF_GPIO
mcp->chip.of_gpio_n_cells = 2;
#endif
mcp->chip.base = base;
mcp->chip.can_sleep = true;
mcp->chip.parent = dev;
mcp->chip.owner = THIS_MODULE;
mcp->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
* and MCP_IOCON.HAEN = 1, so we work with all chips.
*/
ret = mcp_read(mcp, MCP_IOCON, &status);
if (ret < 0)
return dev_err_probe(dev, ret, "can't identify chip %d\n", addr);
mcp->irq_controller =
device_property_read_bool(dev, "interrupt-controller");
if (mcp->irq && mcp->irq_controller) {
mcp->irq_active_high =
device_property_read_bool(dev,
"microchip,irq-active-high");
mirror = device_property_read_bool(dev, "microchip,irq-mirror");
open_drain = device_property_read_bool(dev, "drive-open-drain");
}
if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN) || mirror ||
mcp->irq_active_high || open_drain) {
/* mcp23s17 has IOCON twice, make sure they are in sync */
status &= ~(IOCON_SEQOP | (IOCON_SEQOP << 8));
status |= IOCON_HAEN | (IOCON_HAEN << 8);
if (mcp->irq_active_high)
status |= IOCON_INTPOL | (IOCON_INTPOL << 8);
else
status &= ~(IOCON_INTPOL | (IOCON_INTPOL << 8));
if (mirror)
status |= IOCON_MIRROR | (IOCON_MIRROR << 8);
if (open_drain)
status |= IOCON_ODR | (IOCON_ODR << 8);
if (type == MCP_TYPE_S18 || type == MCP_TYPE_018)
status |= IOCON_INTCC | (IOCON_INTCC << 8);
ret = mcp_write(mcp, MCP_IOCON, status);
if (ret < 0)
return dev_err_probe(dev, ret, "can't write IOCON %d\n", addr);
}
if (mcp->irq && mcp->irq_controller) {
struct gpio_irq_chip *girq = &mcp->chip.irq;
girq->chip = &mcp->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;
}
ret = devm_gpiochip_add_data(dev, &mcp->chip, mcp);
if (ret < 0)
return dev_err_probe(dev, ret, "can't add GPIO chip\n");
mcp->pinctrl_desc.pctlops = &mcp_pinctrl_ops;
mcp->pinctrl_desc.confops = &mcp_pinconf_ops;
mcp->pinctrl_desc.npins = mcp->chip.ngpio;
if (mcp->pinctrl_desc.npins == 8)
mcp->pinctrl_desc.pins = mcp23x08_pins;
else if (mcp->pinctrl_desc.npins == 16)
mcp->pinctrl_desc.pins = mcp23x17_pins;
mcp->pinctrl_desc.owner = THIS_MODULE;
mcp->pctldev = devm_pinctrl_register(dev, &mcp->pinctrl_desc, mcp);
if (IS_ERR(mcp->pctldev))
return dev_err_probe(dev, PTR_ERR(mcp->pctldev), "can't register controller\n");
if (mcp->irq) {
ret = mcp23s08_irq_setup(mcp);
if (ret)
return dev_err_probe(dev, ret, "can't setup IRQ\n");
}
return 0;
}
EXPORT_SYMBOL_GPL(mcp23s08_probe_one);
MODULE_LICENSE("GPL");