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linux/drivers/pinctrl/pinctrl-mcp23s08.c
Jan Kundrát 7547b5969e pinctrl: mcp23s08: debugfs: Do not restore the INTF register 
Apart from the usual stuff, the debugfs code is currently also used for
one non-obvious side effect. It attempts to check whether the chip's
registers are still set to an expected value, and if not, re-initializes
them. It seems that the driver has "always" done so.

The code, however, also checks the INTF register which normally
indicates which pins have caused the recent interrupt. That's a volatile
register, and the datasheet says that writes are ignored in there.

When I'm just cat-ing /sys/kernel/debug/gpio with no SPI traffic and no
nosie on the GPIO lines, I'm not getting any warnings. Once I actually
use these GPIOs and cat that file in parallel, I always seem to get a:

  mcp23s08 spi1.1: restoring reg 0x07 from 0x0000 to 0xffff (power-loss?)

This might be a sign that I should not leave my unused inputs floating,
but the code should not be checking a volatile register, anyway. Let's
simply skip this last item in the iteration. I was also considering
removing this enitre re-initialization because it's non-obvious, but the
code survived various refactorings already and has sign-offs by people
who know more than I do, so let's leave it as-is. For now :).

Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Reviewed-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-06-18 07:56:05 +02:00

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/* MCP23S08 SPI/I2C GPIO driver */
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/gpio.h>
#include <linux/i2c.h>
#include <linux/spi/spi.h>
#include <linux/spi/mcp23s08.h>
#include <linux/slab.h>
#include <asm/byteorder.h>
#include <linux/interrupt.h>
#include <linux/of_device.h>
#include <linux/regmap.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
/*
* MCP types supported by driver
*/
#define MCP_TYPE_S08 0
#define MCP_TYPE_S17 1
#define MCP_TYPE_008 2
#define MCP_TYPE_017 3
#define MCP_TYPE_S18 4
#define MCP_TYPE_018 5
#define MCP_MAX_DEV_PER_CS 8
/* 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
struct mcp23s08;
struct mcp23s08 {
u8 addr;
bool irq_active_high;
bool reg_shift;
u16 irq_rise;
u16 irq_fall;
int irq;
bool irq_controller;
int cached_gpio;
/* lock protects regmap access with bypass/cache flags */
struct mutex lock;
struct gpio_chip chip;
struct regmap *regmap;
struct device *dev;
struct pinctrl_dev *pctldev;
struct pinctrl_desc pinctrl_desc;
};
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,
};
static 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,
};
static const struct reg_default mcp23x16_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 mcp23x16_volatile_range = {
.range_min = MCP_INTF << 1,
.range_max = MCP_GPIO << 1,
};
static const struct regmap_access_table mcp23x16_volatile_table = {
.yes_ranges = &mcp23x16_volatile_range,
.n_yes_ranges = 1,
};
static const struct regmap_range mcp23x16_precious_range = {
.range_min = MCP_GPIO << 1,
.range_max = MCP_GPIO << 1,
};
static const struct regmap_access_table mcp23x16_precious_table = {
.yes_ranges = &mcp23x16_precious_range,
.n_yes_ranges = 1,
};
static const struct regmap_config mcp23x17_regmap = {
.reg_bits = 8,
.val_bits = 16,
.reg_stride = 2,
.max_register = MCP_OLAT << 1,
.volatile_table = &mcp23x16_volatile_table,
.precious_table = &mcp23x16_precious_table,
.reg_defaults = mcp23x16_defaults,
.num_reg_defaults = ARRAY_SIZE(mcp23x16_defaults),
.cache_type = REGCACHE_FLAT,
.val_format_endian = REGMAP_ENDIAN_LITTLE,
};
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:
dev_err(mcp->dev, "Invalid config param %04x\n", param);
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_err(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,
};
/*----------------------------------------------------------------------*/
#ifdef CONFIG_SPI_MASTER
static int mcp23sxx_spi_write(void *context, const void *data, size_t count)
{
struct mcp23s08 *mcp = context;
struct spi_device *spi = to_spi_device(mcp->dev);
struct spi_message m;
struct spi_transfer t[2] = { { .tx_buf = &mcp->addr, .len = 1, },
{ .tx_buf = data, .len = count, }, };
spi_message_init(&m);
spi_message_add_tail(&t[0], &m);
spi_message_add_tail(&t[1], &m);
return spi_sync(spi, &m);
}
static int mcp23sxx_spi_gather_write(void *context,
const void *reg, size_t reg_size,
const void *val, size_t val_size)
{
struct mcp23s08 *mcp = context;
struct spi_device *spi = to_spi_device(mcp->dev);
struct spi_message m;
struct spi_transfer t[3] = { { .tx_buf = &mcp->addr, .len = 1, },
{ .tx_buf = reg, .len = reg_size, },
{ .tx_buf = val, .len = val_size, }, };
spi_message_init(&m);
spi_message_add_tail(&t[0], &m);
spi_message_add_tail(&t[1], &m);
spi_message_add_tail(&t[2], &m);
return spi_sync(spi, &m);
}
static int mcp23sxx_spi_read(void *context, const void *reg, size_t reg_size,
void *val, size_t val_size)
{
struct mcp23s08 *mcp = context;
struct spi_device *spi = to_spi_device(mcp->dev);
u8 tx[2];
if (reg_size != 1)
return -EINVAL;
tx[0] = mcp->addr | 0x01;
tx[1] = *((u8 *) reg);
return spi_write_then_read(spi, tx, sizeof(tx), val, val_size);
}
static const struct regmap_bus mcp23sxx_spi_regmap = {
.write = mcp23sxx_spi_write,
.gather_write = mcp23sxx_spi_gather_write,
.read = mcp23sxx_spi_read,
};
#endif /* CONFIG_SPI_MASTER */
/*----------------------------------------------------------------------*/
/* A given spi_device can represent up to eight mcp23sxx chips
* sharing the same chipselect but using different addresses
* (e.g. chips #0 and #3 might be populated, but not #1 or $2).
* Driver data holds all the per-chip data.
*/
struct mcp23s08_driver_data {
unsigned ngpio;
struct mcp23s08 *mcp[8];
struct mcp23s08 chip[];
};
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 (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);
if (intf == 0) {
/* There is no interrupt pending */
return IRQ_HANDLED;
}
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;
int status = 0;
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 status;
}
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 struct irq_chip mcp23s08_irq_chip = {
.name = "gpio-mcp23xxx",
.irq_mask = mcp23s08_irq_mask,
.irq_unmask = mcp23s08_irq_unmask,
.irq_set_type = mcp23s08_irq_set_type,
.irq_bus_lock = mcp23s08_irq_bus_lock,
.irq_bus_sync_unlock = mcp23s08_irq_bus_unlock,
};
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;
}
err = gpiochip_irqchip_add_nested(chip,
&mcp23s08_irq_chip,
0,
handle_simple_irq,
IRQ_TYPE_NONE);
if (err) {
dev_err(chip->parent,
"could not connect irqchip to gpiochip: %d\n", err);
return err;
}
gpiochip_set_nested_irqchip(chip,
&mcp23s08_irq_chip,
mcp->irq);
return 0;
}
/*----------------------------------------------------------------------*/
#ifdef CONFIG_DEBUG_FS
#include <linux/seq_file.h>
/*
* This compares the chip's registers with the register
* cache and corrects any incorrectly set register. This
* can be used to fix state for MCP23xxx, that temporary
* lost its power supply.
*/
#define MCP23S08_CONFIG_REGS 7
static int __check_mcp23s08_reg_cache(struct mcp23s08 *mcp)
{
int cached[MCP23S08_CONFIG_REGS];
int err = 0, i;
/* read cached config registers */
for (i = 0; i < MCP23S08_CONFIG_REGS; i++) {
err = mcp_read(mcp, i, &cached[i]);
if (err)
goto out;
}
regcache_cache_bypass(mcp->regmap, true);
for (i = 0; i < MCP23S08_CONFIG_REGS; i++) {
int uncached;
err = mcp_read(mcp, i, &uncached);
if (err)
goto out;
if (uncached != cached[i]) {
dev_err(mcp->dev, "restoring reg 0x%02x from 0x%04x to 0x%04x (power-loss?)\n",
i, uncached, cached[i]);
mcp_write(mcp, i, cached[i]);
}
}
out:
if (err)
dev_err(mcp->dev, "read error: reg=%02x, err=%d", i, err);
regcache_cache_bypass(mcp->regmap, false);
return err;
}
/*
* This shows more info than the generic gpio dump code:
* pullups, deglitching, open drain drive.
*/
static void mcp23s08_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
struct mcp23s08 *mcp;
char bank;
int t;
unsigned mask;
int iodir, gpio, gppu;
mcp = gpiochip_get_data(chip);
/* NOTE: we only handle one bank for now ... */
bank = '0' + ((mcp->addr >> 1) & 0x7);
mutex_lock(&mcp->lock);
t = __check_mcp23s08_reg_cache(mcp);
if (t) {
seq_printf(s, " I/O Error\n");
goto done;
}
t = mcp_read(mcp, MCP_IODIR, &iodir);
if (t) {
seq_printf(s, " I/O Error\n");
goto done;
}
t = mcp_read(mcp, MCP_GPIO, &gpio);
if (t) {
seq_printf(s, " I/O Error\n");
goto done;
}
t = mcp_read(mcp, MCP_GPPU, &gppu);
if (t) {
seq_printf(s, " I/O Error\n");
goto done;
}
for (t = 0, mask = BIT(0); t < chip->ngpio; t++, mask <<= 1) {
const char *label;
label = gpiochip_is_requested(chip, t);
if (!label)
continue;
seq_printf(s, " gpio-%-3d P%c.%d (%-12s) %s %s %s\n",
chip->base + t, bank, t, label,
(iodir & mask) ? "in " : "out",
(gpio & mask) ? "hi" : "lo",
(gppu & mask) ? "up" : " ");
/* NOTE: ignoring the irq-related registers */
}
done:
mutex_unlock(&mcp->lock);
}
#else
#define mcp23s08_dbg_show NULL
#endif
/*----------------------------------------------------------------------*/
static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
void *data, unsigned addr, unsigned type,
unsigned int base, int cs)
{
int status, ret;
bool mirror = false;
bool open_drain = false;
struct regmap_config *one_regmap_config = NULL;
int raw_chip_address = (addr & ~0x40) >> 1;
mutex_init(&mcp->lock);
mcp->dev = dev;
mcp->addr = addr;
mcp->irq_active_high = false;
mcp->chip.direction_input = mcp23s08_direction_input;
mcp->chip.get = mcp23s08_get;
mcp->chip.direction_output = mcp23s08_direction_output;
mcp->chip.set = mcp23s08_set;
mcp->chip.dbg_show = mcp23s08_dbg_show;
#ifdef CONFIG_OF_GPIO
mcp->chip.of_gpio_n_cells = 2;
mcp->chip.of_node = dev->of_node;
#endif
switch (type) {
#ifdef CONFIG_SPI_MASTER
case MCP_TYPE_S08:
case MCP_TYPE_S17:
switch (type) {
case MCP_TYPE_S08:
one_regmap_config =
devm_kmemdup(dev, &mcp23x08_regmap,
sizeof(struct regmap_config), GFP_KERNEL);
mcp->reg_shift = 0;
mcp->chip.ngpio = 8;
mcp->chip.label = devm_kasprintf(dev, GFP_KERNEL,
"mcp23s08.%d", raw_chip_address);
break;
case MCP_TYPE_S17:
one_regmap_config =
devm_kmemdup(dev, &mcp23x17_regmap,
sizeof(struct regmap_config), GFP_KERNEL);
mcp->reg_shift = 1;
mcp->chip.ngpio = 16;
mcp->chip.label = devm_kasprintf(dev, GFP_KERNEL,
"mcp23s17.%d", raw_chip_address);
break;
}
if (!one_regmap_config)
return -ENOMEM;
one_regmap_config->name = devm_kasprintf(dev, GFP_KERNEL, "%d", raw_chip_address);
mcp->regmap = devm_regmap_init(dev, &mcp23sxx_spi_regmap, mcp,
one_regmap_config);
break;
case MCP_TYPE_S18:
mcp->regmap = devm_regmap_init(dev, &mcp23sxx_spi_regmap, mcp,
&mcp23x17_regmap);
mcp->reg_shift = 1;
mcp->chip.ngpio = 16;
mcp->chip.label = "mcp23s18";
break;
#endif /* CONFIG_SPI_MASTER */
#if IS_ENABLED(CONFIG_I2C)
case MCP_TYPE_008:
mcp->regmap = devm_regmap_init_i2c(data, &mcp23x08_regmap);
mcp->reg_shift = 0;
mcp->chip.ngpio = 8;
mcp->chip.label = "mcp23008";
break;
case MCP_TYPE_017:
mcp->regmap = devm_regmap_init_i2c(data, &mcp23x17_regmap);
mcp->reg_shift = 1;
mcp->chip.ngpio = 16;
mcp->chip.label = "mcp23017";
break;
case MCP_TYPE_018:
mcp->regmap = devm_regmap_init_i2c(data, &mcp23x17_regmap);
mcp->reg_shift = 1;
mcp->chip.ngpio = 16;
mcp->chip.label = "mcp23018";
break;
#endif /* CONFIG_I2C */
default:
dev_err(dev, "invalid device type (%d)\n", type);
return -EINVAL;
}
if (IS_ERR(mcp->regmap))
return PTR_ERR(mcp->regmap);
mcp->chip.base = base;
mcp->chip.can_sleep = true;
mcp->chip.parent = dev;
mcp->chip.owner = THIS_MODULE;
/* 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)
goto fail;
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)
goto fail;
}
if (mcp->irq && mcp->irq_controller) {
ret = mcp23s08_irq_setup(mcp);
if (ret)
goto fail;
}
ret = devm_gpiochip_add_data(dev, &mcp->chip, mcp);
if (ret < 0)
goto fail;
if (one_regmap_config) {
mcp->pinctrl_desc.name = devm_kasprintf(dev, GFP_KERNEL,
"mcp23xxx-pinctrl.%d", raw_chip_address);
if (!mcp->pinctrl_desc.name)
return -ENOMEM;
} else {
mcp->pinctrl_desc.name = "mcp23xxx-pinctrl";
}
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)) {
ret = PTR_ERR(mcp->pctldev);
goto fail;
}
fail:
if (ret < 0)
dev_dbg(dev, "can't setup chip %d, --> %d\n", addr, ret);
return ret;
}
/*----------------------------------------------------------------------*/
#ifdef CONFIG_OF
#ifdef CONFIG_SPI_MASTER
static const struct of_device_id mcp23s08_spi_of_match[] = {
{
.compatible = "microchip,mcp23s08",
.data = (void *) MCP_TYPE_S08,
},
{
.compatible = "microchip,mcp23s17",
.data = (void *) MCP_TYPE_S17,
},
{
.compatible = "microchip,mcp23s18",
.data = (void *) MCP_TYPE_S18,
},
/* NOTE: The use of the mcp prefix is deprecated and will be removed. */
{
.compatible = "mcp,mcp23s08",
.data = (void *) MCP_TYPE_S08,
},
{
.compatible = "mcp,mcp23s17",
.data = (void *) MCP_TYPE_S17,
},
{ },
};
MODULE_DEVICE_TABLE(of, mcp23s08_spi_of_match);
#endif
#if IS_ENABLED(CONFIG_I2C)
static const struct of_device_id mcp23s08_i2c_of_match[] = {
{
.compatible = "microchip,mcp23008",
.data = (void *) MCP_TYPE_008,
},
{
.compatible = "microchip,mcp23017",
.data = (void *) MCP_TYPE_017,
},
{
.compatible = "microchip,mcp23018",
.data = (void *) MCP_TYPE_018,
},
/* NOTE: The use of the mcp prefix is deprecated and will be removed. */
{
.compatible = "mcp,mcp23008",
.data = (void *) MCP_TYPE_008,
},
{
.compatible = "mcp,mcp23017",
.data = (void *) MCP_TYPE_017,
},
{ },
};
MODULE_DEVICE_TABLE(of, mcp23s08_i2c_of_match);
#endif
#endif /* CONFIG_OF */
#if IS_ENABLED(CONFIG_I2C)
static int mcp230xx_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct mcp23s08_platform_data *pdata, local_pdata;
struct mcp23s08 *mcp;
int status;
pdata = dev_get_platdata(&client->dev);
if (!pdata) {
pdata = &local_pdata;
pdata->base = -1;
}
mcp = devm_kzalloc(&client->dev, sizeof(*mcp), GFP_KERNEL);
if (!mcp)
return -ENOMEM;
mcp->irq = client->irq;
status = mcp23s08_probe_one(mcp, &client->dev, client, client->addr,
id->driver_data, pdata->base, 0);
if (status)
return status;
i2c_set_clientdata(client, mcp);
return 0;
}
static const struct i2c_device_id mcp230xx_id[] = {
{ "mcp23008", MCP_TYPE_008 },
{ "mcp23017", MCP_TYPE_017 },
{ "mcp23018", MCP_TYPE_018 },
{ },
};
MODULE_DEVICE_TABLE(i2c, mcp230xx_id);
static struct i2c_driver mcp230xx_driver = {
.driver = {
.name = "mcp230xx",
.of_match_table = of_match_ptr(mcp23s08_i2c_of_match),
},
.probe = mcp230xx_probe,
.id_table = mcp230xx_id,
};
static int __init mcp23s08_i2c_init(void)
{
return i2c_add_driver(&mcp230xx_driver);
}
static void mcp23s08_i2c_exit(void)
{
i2c_del_driver(&mcp230xx_driver);
}
#else
static int __init mcp23s08_i2c_init(void) { return 0; }
static void mcp23s08_i2c_exit(void) { }
#endif /* CONFIG_I2C */
/*----------------------------------------------------------------------*/
#ifdef CONFIG_SPI_MASTER
static int mcp23s08_probe(struct spi_device *spi)
{
struct mcp23s08_platform_data *pdata, local_pdata;
unsigned addr;
int chips = 0;
struct mcp23s08_driver_data *data;
int status, type;
unsigned ngpio = 0;
const struct of_device_id *match;
match = of_match_device(of_match_ptr(mcp23s08_spi_of_match), &spi->dev);
if (match)
type = (int)(uintptr_t)match->data;
else
type = spi_get_device_id(spi)->driver_data;
pdata = dev_get_platdata(&spi->dev);
if (!pdata) {
pdata = &local_pdata;
pdata->base = -1;
status = device_property_read_u32(&spi->dev,
"microchip,spi-present-mask", &pdata->spi_present_mask);
if (status) {
status = device_property_read_u32(&spi->dev,
"mcp,spi-present-mask",
&pdata->spi_present_mask);
if (status) {
dev_err(&spi->dev, "missing spi-present-mask");
return -ENODEV;
}
}
}
if (!pdata->spi_present_mask || pdata->spi_present_mask > 0xff) {
dev_err(&spi->dev, "invalid spi-present-mask");
return -ENODEV;
}
for (addr = 0; addr < MCP_MAX_DEV_PER_CS; addr++) {
if (pdata->spi_present_mask & BIT(addr))
chips++;
}
if (!chips)
return -ENODEV;
data = devm_kzalloc(&spi->dev,
sizeof(*data) + chips * sizeof(struct mcp23s08),
GFP_KERNEL);
if (!data)
return -ENOMEM;
spi_set_drvdata(spi, data);
for (addr = 0; addr < MCP_MAX_DEV_PER_CS; addr++) {
if (!(pdata->spi_present_mask & BIT(addr)))
continue;
chips--;
data->mcp[addr] = &data->chip[chips];
data->mcp[addr]->irq = spi->irq;
status = mcp23s08_probe_one(data->mcp[addr], &spi->dev, spi,
0x40 | (addr << 1), type,
pdata->base, addr);
if (status < 0)
return status;
if (pdata->base != -1)
pdata->base += data->mcp[addr]->chip.ngpio;
ngpio += data->mcp[addr]->chip.ngpio;
}
data->ngpio = ngpio;
return 0;
}
static const struct spi_device_id mcp23s08_ids[] = {
{ "mcp23s08", MCP_TYPE_S08 },
{ "mcp23s17", MCP_TYPE_S17 },
{ "mcp23s18", MCP_TYPE_S18 },
{ },
};
MODULE_DEVICE_TABLE(spi, mcp23s08_ids);
static struct spi_driver mcp23s08_driver = {
.probe = mcp23s08_probe,
.id_table = mcp23s08_ids,
.driver = {
.name = "mcp23s08",
.of_match_table = of_match_ptr(mcp23s08_spi_of_match),
},
};
static int __init mcp23s08_spi_init(void)
{
return spi_register_driver(&mcp23s08_driver);
}
static void mcp23s08_spi_exit(void)
{
spi_unregister_driver(&mcp23s08_driver);
}
#else
static int __init mcp23s08_spi_init(void) { return 0; }
static void mcp23s08_spi_exit(void) { }
#endif /* CONFIG_SPI_MASTER */
/*----------------------------------------------------------------------*/
static int __init mcp23s08_init(void)
{
int ret;
ret = mcp23s08_spi_init();
if (ret)
goto spi_fail;
ret = mcp23s08_i2c_init();
if (ret)
goto i2c_fail;
return 0;
i2c_fail:
mcp23s08_spi_exit();
spi_fail:
return ret;
}
/* register after spi/i2c postcore initcall and before
* subsys initcalls that may rely on these GPIOs
*/
subsys_initcall(mcp23s08_init);
static void __exit mcp23s08_exit(void)
{
mcp23s08_spi_exit();
mcp23s08_i2c_exit();
}
module_exit(mcp23s08_exit);
MODULE_LICENSE("GPL");
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