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alistair23-linux/drivers/gpio/gpio-mcp23s08.c
Linus Torvalds 80fb974798 This is the bulk of GPIO changes for the v3.16 series: 
- We are finalizing and fixing up the gpiochip irqchip helpers
   bringing a helpful irqchip implementation into the gpiolib
   core and avoiding duplicate code and, more importantly,
   duplicate bug fixes:
 
   - Support for using the helpers with threaded interrupt
     handlers as used on sleeping GPIO-irqchips
 
   - Do not set up hardware triggers for edges or levels if
     the default IRQ type is IRQ_TYPE_NONE - some drivers
     would exploit the fact that you could get default
     initialization of the IRQ type from the core at probe()
     but if no default type is set up from the helper, we
     should not call the driver to configure anything. Wait
     until a consumer requests the interrupt instead.
 
   - Make the irqchip helpers put the GPIO irqs into their
     own lock class. The GPIO irqchips can often emit
     (harmless, but annoying) lockdep warnings about recursions
     when they are in fact just cascaded IRQs. By putting
     them into their own lock class we help the lockdep core
     to keep track of things.
 
   - Switch the tc3589x GPIO expanders to use the irqchip
     helpers
 
   - Switch the OMAP GPIO driver to use the irqchip helpers
 
   - Add some documentation for the irqchip helpers
 
   - select IRQ_DOMAIN when using the helpers since some
     platforms may not be using this by default and it's a
     strict dependency.
 
 - Continued GPIO descriptor refactoring:
 
   - Remove the one instance of gpio_to_desc() from the
     device tree code, making the OF GPIO code use GPIO
     descriptors only.
 
   - Introduce gpiod_get_optional() and
     gpiod_get_optional_index() akin to the similar
     regulator functions for cases where the use of GPIO
     is optional and not strictly required.
 
   - Make of_get_named_gpiod_flags() private - we do not
     want to unnecessarily expose APIs to drivers that
     make the gpiolib harder than necessary to maintain
     and refactor. Privatize this function.
 
 - Support "-gpio" suffix for the OF GPIO retrieveal path.
   We used to look for "foo-gpios" or just "gpios" in device
   tree nodes, but it turns out that some drivers with a
   single GPIO line will just state "foo-gpio" (singularis).
   Sigh. Support this with a fallback looking for it, as
   this simplifies driver code and handles it in core code.
 
 - Switch the ACPI GPIO core to fetch GPIOs with the
   *_cansleep function variants as the GPIO operation
   region handler can sleep, and shall be able to handle
   gpiochips that sleep.
 
 - Tons of cleanups and janitorial work from Jingoo Han,
   Axel Lin, Javier Martinez Canillas and Abdoulaye Berthe.
   Notably Jingoo cut off a ton of pointless OOM messages.
 
 - Incremental development and fixes for various drivers,
   nothing really special here.
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Merge tag 'gpio-v3.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio into next

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v3.16 series.

  There is a lot of action in the GPIO subsystem doing refactorings and
  cleanups, almost as many deletions as insertions and minor feature
  growth and no new drivers this time.  Which is actually pretty nice.
  Some GPIO-related stuff will come in through the pin control tree as
  well.

  Details:

   - We are finalizing and fixing up the gpiochip irqchip helpers
     bringing a helpful irqchip implementation into the gpiolib core and
     avoiding duplicate code and, more importantly, duplicate bug fixes:

     * Support for using the helpers with threaded interrupt handlers as
       used on sleeping GPIO-irqchips

     * Do not set up hardware triggers for edges or levels if the
       default IRQ type is IRQ_TYPE_NONE - some drivers would exploit
       the fact that you could get default initialization of the IRQ
       type from the core at probe() but if no default type is set up
       from the helper, we should not call the driver to configure
       anything.  Wait until a consumer requests the interrupt instead.

     * Make the irqchip helpers put the GPIO irqs into their own lock
       class.  The GPIO irqchips can often emit (harmless, but annoying)
       lockdep warnings about recursions when they are in fact just
       cascaded IRQs.  By putting them into their own lock class we help
       the lockdep core to keep track of things.

     * Switch the tc3589x GPIO expanders to use the irqchip helpers

     * Switch the OMAP GPIO driver to use the irqchip helpers

     * Add some documentation for the irqchip helpers

     * select IRQ_DOMAIN when using the helpers since some platforms may
       not be using this by default and it's a strict dependency.

   - Continued GPIO descriptor refactoring:

     * Remove the one instance of gpio_to_desc() from the device tree
       code, making the OF GPIO code use GPIO descriptors only.

     * Introduce gpiod_get_optional() and gpiod_get_optional_index()
       akin to the similar regulator functions for cases where the use
       of GPIO is optional and not strictly required.

     * Make of_get_named_gpiod_flags() private - we do not want to
       unnecessarily expose APIs to drivers that make the gpiolib harder
       than necessary to maintain and refactor.  Privatize this
       function.

   - Support "-gpio" suffix for the OF GPIO retrieveal path.  We used to
     look for "foo-gpios" or just "gpios" in device tree nodes, but it
     turns out that some drivers with a single GPIO line will just state
     "foo-gpio" (singularis).  Sigh.  Support this with a fallback
     looking for it, as this simplifies driver code and handles it in
     core code.

   - Switch the ACPI GPIO core to fetch GPIOs with the *_cansleep
     function variants as the GPIO operation region handler can sleep,
     and shall be able to handle gpiochips that sleep.

   - Tons of cleanups and janitorial work from Jingoo Han, Axel Lin,
     Javier Martinez Canillas and Abdoulaye Berthe.  Notably Jingoo cut
     off a ton of pointless OOM messages.

   - Incremental development and fixes for various drivers, nothing
     really special here"

* tag 'gpio-v3.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (85 commits)
  gpio: select IRQ_DOMAIN for gpiolib irqchip helpers
  gpio: pca953x: use gpiolib irqchip helpers
  gpio: pcf857x: Add IRQF_SHARED when request irq
  gpio: pcf857x: Avoid calling irq_domain_cleanup twice
  gpio: mcp23s08: switch chip count to int
  gpio: dwapb: use a second irq chip
  gpio: ep93xx: Use devm_ioremap_resource()
  gpio: mcp23s08: fixed count variable for devicetree probing
  gpio: Add run-time dependencies to R-Car driver
  gpio: pch: add slab include
  Documentation / ACPI: Fix location of GPIO documentation
  gpio / ACPI: use *_cansleep version of gpiod_get/set APIs
  gpio: generic: add request function pointer
  gpio-pch: Fix Kconfig dependencies
  gpio: make of_get_named_gpiod_flags() private
  gpio: gpioep93xx: use devm functions
  gpio: janzttl: use devm function
  gpio: timberdale: use devm functions
  gpio: bt8xx: use devm function for memory allocation
  gpio: include linux/bug.h in interface header
  ...
2014-06-02 08:46:03 -07:00

1073 lines
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/*
* MCP23S08 SPI/I2C GPIO gpio expander driver
*
* The inputs and outputs of the mcp23s08, mcp23s17, mcp23008 and mcp23017 are
* supported.
* For the I2C versions of the chips (mcp23008 and mcp23017) generation of
* interrupts is also supported.
* The hardware of the SPI versions of the chips (mcp23s08 and mcp23s17) is
* also capable of generating interrupts, but the linux driver does not
* support that yet.
*/
#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_irq.h>
#include <linux/of_device.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
/* 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 MCP_GPPU 0x06
#define MCP_INTF 0x07
#define MCP_INTCAP 0x08
#define MCP_GPIO 0x09
#define MCP_OLAT 0x0a
struct mcp23s08;
struct mcp23s08_ops {
int (*read)(struct mcp23s08 *mcp, unsigned reg);
int (*write)(struct mcp23s08 *mcp, unsigned reg, unsigned val);
int (*read_regs)(struct mcp23s08 *mcp, unsigned reg,
u16 *vals, unsigned n);
};
struct mcp23s08 {
u8 addr;
u16 cache[11];
u16 irq_rise;
u16 irq_fall;
int irq;
bool irq_controller;
/* lock protects the cached values */
struct mutex lock;
struct mutex irq_lock;
struct irq_domain *irq_domain;
struct gpio_chip chip;
const struct mcp23s08_ops *ops;
void *data; /* ops specific data */
};
/* 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[];
};
/* This lock class tells lockdep that GPIO irqs are in a different
* category than their parents, so it won't report false recursion.
*/
static struct lock_class_key gpio_lock_class;
/*----------------------------------------------------------------------*/
#if IS_ENABLED(CONFIG_I2C)
static int mcp23008_read(struct mcp23s08 *mcp, unsigned reg)
{
return i2c_smbus_read_byte_data(mcp->data, reg);
}
static int mcp23008_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
{
return i2c_smbus_write_byte_data(mcp->data, reg, val);
}
static int
mcp23008_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
{
while (n--) {
int ret = mcp23008_read(mcp, reg++);
if (ret < 0)
return ret;
*vals++ = ret;
}
return 0;
}
static int mcp23017_read(struct mcp23s08 *mcp, unsigned reg)
{
return i2c_smbus_read_word_data(mcp->data, reg << 1);
}
static int mcp23017_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
{
return i2c_smbus_write_word_data(mcp->data, reg << 1, val);
}
static int
mcp23017_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
{
while (n--) {
int ret = mcp23017_read(mcp, reg++);
if (ret < 0)
return ret;
*vals++ = ret;
}
return 0;
}
static const struct mcp23s08_ops mcp23008_ops = {
.read = mcp23008_read,
.write = mcp23008_write,
.read_regs = mcp23008_read_regs,
};
static const struct mcp23s08_ops mcp23017_ops = {
.read = mcp23017_read,
.write = mcp23017_write,
.read_regs = mcp23017_read_regs,
};
#endif /* CONFIG_I2C */
/*----------------------------------------------------------------------*/
#ifdef CONFIG_SPI_MASTER
static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg)
{
u8 tx[2], rx[1];
int status;
tx[0] = mcp->addr | 0x01;
tx[1] = reg;
status = spi_write_then_read(mcp->data, tx, sizeof(tx), rx, sizeof(rx));
return (status < 0) ? status : rx[0];
}
static int mcp23s08_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
{
u8 tx[3];
tx[0] = mcp->addr;
tx[1] = reg;
tx[2] = val;
return spi_write_then_read(mcp->data, tx, sizeof(tx), NULL, 0);
}
static int
mcp23s08_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
{
u8 tx[2], *tmp;
int status;
if ((n + reg) > sizeof(mcp->cache))
return -EINVAL;
tx[0] = mcp->addr | 0x01;
tx[1] = reg;
tmp = (u8 *)vals;
status = spi_write_then_read(mcp->data, tx, sizeof(tx), tmp, n);
if (status >= 0) {
while (n--)
vals[n] = tmp[n]; /* expand to 16bit */
}
return status;
}
static int mcp23s17_read(struct mcp23s08 *mcp, unsigned reg)
{
u8 tx[2], rx[2];
int status;
tx[0] = mcp->addr | 0x01;
tx[1] = reg << 1;
status = spi_write_then_read(mcp->data, tx, sizeof(tx), rx, sizeof(rx));
return (status < 0) ? status : (rx[0] | (rx[1] << 8));
}
static int mcp23s17_write(struct mcp23s08 *mcp, unsigned reg, unsigned val)
{
u8 tx[4];
tx[0] = mcp->addr;
tx[1] = reg << 1;
tx[2] = val;
tx[3] = val >> 8;
return spi_write_then_read(mcp->data, tx, sizeof(tx), NULL, 0);
}
static int
mcp23s17_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n)
{
u8 tx[2];
int status;
if ((n + reg) > sizeof(mcp->cache))
return -EINVAL;
tx[0] = mcp->addr | 0x01;
tx[1] = reg << 1;
status = spi_write_then_read(mcp->data, tx, sizeof(tx),
(u8 *)vals, n * 2);
if (status >= 0) {
while (n--)
vals[n] = __le16_to_cpu((__le16)vals[n]);
}
return status;
}
static const struct mcp23s08_ops mcp23s08_ops = {
.read = mcp23s08_read,
.write = mcp23s08_write,
.read_regs = mcp23s08_read_regs,
};
static const struct mcp23s08_ops mcp23s17_ops = {
.read = mcp23s17_read,
.write = mcp23s17_write,
.read_regs = mcp23s17_read_regs,
};
#endif /* CONFIG_SPI_MASTER */
/*----------------------------------------------------------------------*/
static int mcp23s08_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
int status;
mutex_lock(&mcp->lock);
mcp->cache[MCP_IODIR] |= (1 << offset);
status = mcp->ops->write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
mutex_unlock(&mcp->lock);
return status;
}
static int mcp23s08_get(struct gpio_chip *chip, unsigned offset)
{
struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
int status;
mutex_lock(&mcp->lock);
/* REVISIT reading this clears any IRQ ... */
status = mcp->ops->read(mcp, MCP_GPIO);
if (status < 0)
status = 0;
else {
mcp->cache[MCP_GPIO] = status;
status = !!(status & (1 << offset));
}
mutex_unlock(&mcp->lock);
return status;
}
static int __mcp23s08_set(struct mcp23s08 *mcp, unsigned mask, int value)
{
unsigned olat = mcp->cache[MCP_OLAT];
if (value)
olat |= mask;
else
olat &= ~mask;
mcp->cache[MCP_OLAT] = olat;
return mcp->ops->write(mcp, MCP_OLAT, olat);
}
static void mcp23s08_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
unsigned mask = 1 << 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 = container_of(chip, struct mcp23s08, chip);
unsigned mask = 1 << offset;
int status;
mutex_lock(&mcp->lock);
status = __mcp23s08_set(mcp, mask, value);
if (status == 0) {
mcp->cache[MCP_IODIR] &= ~mask;
status = mcp->ops->write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
}
mutex_unlock(&mcp->lock);
return status;
}
/*----------------------------------------------------------------------*/
static irqreturn_t mcp23s08_irq(int irq, void *data)
{
struct mcp23s08 *mcp = data;
int intcap, intf, i;
unsigned int child_irq;
mutex_lock(&mcp->lock);
intf = mcp->ops->read(mcp, MCP_INTF);
if (intf < 0) {
mutex_unlock(&mcp->lock);
return IRQ_HANDLED;
}
mcp->cache[MCP_INTF] = intf;
intcap = mcp->ops->read(mcp, MCP_INTCAP);
if (intcap < 0) {
mutex_unlock(&mcp->lock);
return IRQ_HANDLED;
}
mcp->cache[MCP_INTCAP] = intcap;
mutex_unlock(&mcp->lock);
for (i = 0; i < mcp->chip.ngpio; i++) {
if ((BIT(i) & mcp->cache[MCP_INTF]) &&
((BIT(i) & intcap & mcp->irq_rise) ||
(mcp->irq_fall & ~intcap & BIT(i)))) {
child_irq = irq_find_mapping(mcp->irq_domain, i);
handle_nested_irq(child_irq);
}
}
return IRQ_HANDLED;
}
static int mcp23s08_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
return irq_find_mapping(mcp->irq_domain, offset);
}
static void mcp23s08_irq_mask(struct irq_data *data)
{
struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
unsigned int pos = data->hwirq;
mcp->cache[MCP_GPINTEN] &= ~BIT(pos);
}
static void mcp23s08_irq_unmask(struct irq_data *data)
{
struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
unsigned int pos = data->hwirq;
mcp->cache[MCP_GPINTEN] |= BIT(pos);
}
static int mcp23s08_irq_set_type(struct irq_data *data, unsigned int type)
{
struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
unsigned int pos = data->hwirq;
int status = 0;
if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
mcp->cache[MCP_INTCON] &= ~BIT(pos);
mcp->irq_rise |= BIT(pos);
mcp->irq_fall |= BIT(pos);
} else if (type & IRQ_TYPE_EDGE_RISING) {
mcp->cache[MCP_INTCON] &= ~BIT(pos);
mcp->irq_rise |= BIT(pos);
mcp->irq_fall &= ~BIT(pos);
} else if (type & IRQ_TYPE_EDGE_FALLING) {
mcp->cache[MCP_INTCON] &= ~BIT(pos);
mcp->irq_rise &= ~BIT(pos);
mcp->irq_fall |= BIT(pos);
} else
return -EINVAL;
return status;
}
static void mcp23s08_irq_bus_lock(struct irq_data *data)
{
struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
mutex_lock(&mcp->irq_lock);
}
static void mcp23s08_irq_bus_unlock(struct irq_data *data)
{
struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
mutex_lock(&mcp->lock);
mcp->ops->write(mcp, MCP_GPINTEN, mcp->cache[MCP_GPINTEN]);
mcp->ops->write(mcp, MCP_DEFVAL, mcp->cache[MCP_DEFVAL]);
mcp->ops->write(mcp, MCP_INTCON, mcp->cache[MCP_INTCON]);
mutex_unlock(&mcp->lock);
mutex_unlock(&mcp->irq_lock);
}
static int mcp23s08_irq_reqres(struct irq_data *data)
{
struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
if (gpio_lock_as_irq(&mcp->chip, data->hwirq)) {
dev_err(mcp->chip.dev,
"unable to lock HW IRQ %lu for IRQ usage\n",
data->hwirq);
return -EINVAL;
}
return 0;
}
static void mcp23s08_irq_relres(struct irq_data *data)
{
struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
gpio_unlock_as_irq(&mcp->chip, data->hwirq);
}
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,
.irq_request_resources = mcp23s08_irq_reqres,
.irq_release_resources = mcp23s08_irq_relres,
};
static int mcp23s08_irq_setup(struct mcp23s08 *mcp)
{
struct gpio_chip *chip = &mcp->chip;
int err, irq, j;
mutex_init(&mcp->irq_lock);
mcp->irq_domain = irq_domain_add_linear(chip->of_node, chip->ngpio,
&irq_domain_simple_ops, mcp);
if (!mcp->irq_domain)
return -ENODEV;
err = devm_request_threaded_irq(chip->dev, mcp->irq, NULL, mcp23s08_irq,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
dev_name(chip->dev), mcp);
if (err != 0) {
dev_err(chip->dev, "unable to request IRQ#%d: %d\n",
mcp->irq, err);
return err;
}
chip->to_irq = mcp23s08_gpio_to_irq;
for (j = 0; j < mcp->chip.ngpio; j++) {
irq = irq_create_mapping(mcp->irq_domain, j);
irq_set_lockdep_class(irq, &gpio_lock_class);
irq_set_chip_data(irq, mcp);
irq_set_chip(irq, &mcp23s08_irq_chip);
irq_set_nested_thread(irq, true);
#ifdef CONFIG_ARM
set_irq_flags(irq, IRQF_VALID);
#else
irq_set_noprobe(irq);
#endif
}
return 0;
}
static void mcp23s08_irq_teardown(struct mcp23s08 *mcp)
{
unsigned int irq, i;
free_irq(mcp->irq, mcp);
for (i = 0; i < mcp->chip.ngpio; i++) {
irq = irq_find_mapping(mcp->irq_domain, i);
if (irq > 0)
irq_dispose_mapping(irq);
}
irq_domain_remove(mcp->irq_domain);
}
/*----------------------------------------------------------------------*/
#ifdef CONFIG_DEBUG_FS
#include <linux/seq_file.h>
/*
* 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;
mcp = container_of(chip, struct mcp23s08, chip);
/* NOTE: we only handle one bank for now ... */
bank = '0' + ((mcp->addr >> 1) & 0x7);
mutex_lock(&mcp->lock);
t = mcp->ops->read_regs(mcp, 0, mcp->cache, ARRAY_SIZE(mcp->cache));
if (t < 0) {
seq_printf(s, " I/O ERROR %d\n", t);
goto done;
}
for (t = 0, mask = 1; 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",
chip->base + t, bank, t, label,
(mcp->cache[MCP_IODIR] & mask) ? "in " : "out",
(mcp->cache[MCP_GPIO] & mask) ? "hi" : "lo",
(mcp->cache[MCP_GPPU] & mask) ? "up" : " ");
/* NOTE: ignoring the irq-related registers */
seq_puts(s, "\n");
}
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 base, unsigned pullups)
{
int status;
bool mirror = false;
mutex_init(&mcp->lock);
mcp->data = data;
mcp->addr = addr;
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
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:
mcp->ops = &mcp23s08_ops;
mcp->chip.ngpio = 8;
mcp->chip.label = "mcp23s08";
break;
case MCP_TYPE_S17:
mcp->ops = &mcp23s17_ops;
mcp->chip.ngpio = 16;
mcp->chip.label = "mcp23s17";
break;
#endif /* CONFIG_SPI_MASTER */
#if IS_ENABLED(CONFIG_I2C)
case MCP_TYPE_008:
mcp->ops = &mcp23008_ops;
mcp->chip.ngpio = 8;
mcp->chip.label = "mcp23008";
break;
case MCP_TYPE_017:
mcp->ops = &mcp23017_ops;
mcp->chip.ngpio = 16;
mcp->chip.label = "mcp23017";
break;
#endif /* CONFIG_I2C */
default:
dev_err(dev, "invalid device type (%d)\n", type);
return -EINVAL;
}
mcp->chip.base = base;
mcp->chip.can_sleep = true;
mcp->chip.dev = 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.
*/
status = mcp->ops->read(mcp, MCP_IOCON);
if (status < 0)
goto fail;
mcp->irq_controller = of_property_read_bool(mcp->chip.of_node,
"interrupt-controller");
if (mcp->irq && mcp->irq_controller && (type == MCP_TYPE_017))
mirror = of_property_read_bool(mcp->chip.of_node,
"microchip,irq-mirror");
if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN) || mirror) {
/* mcp23s17 has IOCON twice, make sure they are in sync */
status &= ~(IOCON_SEQOP | (IOCON_SEQOP << 8));
status |= IOCON_HAEN | (IOCON_HAEN << 8);
status &= ~(IOCON_INTPOL | (IOCON_INTPOL << 8));
if (mirror)
status |= IOCON_MIRROR | (IOCON_MIRROR << 8);
status = mcp->ops->write(mcp, MCP_IOCON, status);
if (status < 0)
goto fail;
}
/* configure ~100K pullups */
status = mcp->ops->write(mcp, MCP_GPPU, pullups);
if (status < 0)
goto fail;
status = mcp->ops->read_regs(mcp, 0, mcp->cache, ARRAY_SIZE(mcp->cache));
if (status < 0)
goto fail;
/* disable inverter on input */
if (mcp->cache[MCP_IPOL] != 0) {
mcp->cache[MCP_IPOL] = 0;
status = mcp->ops->write(mcp, MCP_IPOL, 0);
if (status < 0)
goto fail;
}
/* disable irqs */
if (mcp->cache[MCP_GPINTEN] != 0) {
mcp->cache[MCP_GPINTEN] = 0;
status = mcp->ops->write(mcp, MCP_GPINTEN, 0);
if (status < 0)
goto fail;
}
status = gpiochip_add(&mcp->chip);
if (status < 0)
goto fail;
if (mcp->irq && mcp->irq_controller) {
status = mcp23s08_irq_setup(mcp);
if (status) {
mcp23s08_irq_teardown(mcp);
goto fail;
}
}
fail:
if (status < 0)
dev_dbg(dev, "can't setup chip %d, --> %d\n",
addr, status);
return status;
}
/*----------------------------------------------------------------------*/
#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,
},
/* 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,
},
/* 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;
struct mcp23s08 *mcp;
int status, base, pullups;
const struct of_device_id *match;
match = of_match_device(of_match_ptr(mcp23s08_i2c_of_match),
&client->dev);
pdata = dev_get_platdata(&client->dev);
if (match || !pdata) {
base = -1;
pullups = 0;
client->irq = irq_of_parse_and_map(client->dev.of_node, 0);
} else {
if (!gpio_is_valid(pdata->base)) {
dev_dbg(&client->dev, "invalid platform data\n");
return -EINVAL;
}
base = pdata->base;
pullups = pdata->chip[0].pullups;
}
mcp = kzalloc(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, base, pullups);
if (status)
goto fail;
i2c_set_clientdata(client, mcp);
return 0;
fail:
kfree(mcp);
return status;
}
static int mcp230xx_remove(struct i2c_client *client)
{
struct mcp23s08 *mcp = i2c_get_clientdata(client);
int status;
if (client->irq && mcp->irq_controller)
mcp23s08_irq_teardown(mcp);
status = gpiochip_remove(&mcp->chip);
if (status == 0)
kfree(mcp);
return status;
}
static const struct i2c_device_id mcp230xx_id[] = {
{ "mcp23008", MCP_TYPE_008 },
{ "mcp23017", MCP_TYPE_017 },
{ },
};
MODULE_DEVICE_TABLE(i2c, mcp230xx_id);
static struct i2c_driver mcp230xx_driver = {
.driver = {
.name = "mcp230xx",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(mcp23s08_i2c_of_match),
},
.probe = mcp230xx_probe,
.remove = mcp230xx_remove,
.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;
unsigned addr;
int chips = 0;
struct mcp23s08_driver_data *data;
int status, type;
unsigned base = -1,
ngpio = 0,
pullups[ARRAY_SIZE(pdata->chip)];
const struct of_device_id *match;
u32 spi_present_mask = 0;
match = of_match_device(of_match_ptr(mcp23s08_spi_of_match), &spi->dev);
if (match) {
type = (int)(uintptr_t)match->data;
status = of_property_read_u32(spi->dev.of_node,
"microchip,spi-present-mask", &spi_present_mask);
if (status) {
status = of_property_read_u32(spi->dev.of_node,
"mcp,spi-present-mask", &spi_present_mask);
if (status) {
dev_err(&spi->dev,
"DT has no spi-present-mask\n");
return -ENODEV;
}
}
if ((spi_present_mask <= 0) || (spi_present_mask >= 256)) {
dev_err(&spi->dev, "invalid spi-present-mask\n");
return -ENODEV;
}
for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) {
pullups[addr] = 0;
if (spi_present_mask & (1 << addr))
chips++;
}
if (!chips)
return -ENODEV;
} else {
type = spi_get_device_id(spi)->driver_data;
pdata = dev_get_platdata(&spi->dev);
if (!pdata || !gpio_is_valid(pdata->base)) {
dev_dbg(&spi->dev,
"invalid or missing platform data\n");
return -EINVAL;
}
for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) {
if (!pdata->chip[addr].is_present)
continue;
chips++;
if ((type == MCP_TYPE_S08) && (addr > 3)) {
dev_err(&spi->dev,
"mcp23s08 only supports address 0..3\n");
return -EINVAL;
}
spi_present_mask |= 1 << addr;
pullups[addr] = pdata->chip[addr].pullups;
}
base = pdata->base;
}
if (!chips)
return -ENODEV;
data = kzalloc(sizeof(*data) + chips * sizeof(struct mcp23s08),
GFP_KERNEL);
if (!data)
return -ENOMEM;
spi_set_drvdata(spi, data);
for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) {
if (!(spi_present_mask & (1 << addr)))
continue;
chips--;
if (chips < 0) {
dev_err(&spi->dev, "FATAL: invalid negative chip id\n");
goto fail;
}
data->mcp[addr] = &data->chip[chips];
status = mcp23s08_probe_one(data->mcp[addr], &spi->dev, spi,
0x40 | (addr << 1), type, base,
pullups[addr]);
if (status < 0)
goto fail;
if (base != -1)
base += (type == MCP_TYPE_S17) ? 16 : 8;
ngpio += (type == MCP_TYPE_S17) ? 16 : 8;
}
data->ngpio = ngpio;
/* NOTE: these chips have a relatively sane IRQ framework, with
* per-signal masking and level/edge triggering. It's not yet
* handled here...
*/
return 0;
fail:
for (addr = 0; addr < ARRAY_SIZE(data->mcp); addr++) {
int tmp;
if (!data->mcp[addr])
continue;
tmp = gpiochip_remove(&data->mcp[addr]->chip);
if (tmp < 0)
dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
}
kfree(data);
return status;
}
static int mcp23s08_remove(struct spi_device *spi)
{
struct mcp23s08_driver_data *data = spi_get_drvdata(spi);
unsigned addr;
int status = 0;
for (addr = 0; addr < ARRAY_SIZE(data->mcp); addr++) {
int tmp;
if (!data->mcp[addr])
continue;
tmp = gpiochip_remove(&data->mcp[addr]->chip);
if (tmp < 0) {
dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
status = tmp;
}
}
if (status == 0)
kfree(data);
return status;
}
static const struct spi_device_id mcp23s08_ids[] = {
{ "mcp23s08", MCP_TYPE_S08 },
{ "mcp23s17", MCP_TYPE_S17 },
{ },
};
MODULE_DEVICE_TABLE(spi, mcp23s08_ids);
static struct spi_driver mcp23s08_driver = {
.probe = mcp23s08_probe,
.remove = mcp23s08_remove,
.id_table = mcp23s08_ids,
.driver = {
.name = "mcp23s08",
.owner = THIS_MODULE,
.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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