/*
- * MCP23S08 SPI/GPIO gpio expander driver
+ * 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/spi/mcp23s08.h>
#include <linux/slab.h>
#include <asm/byteorder.h>
-#include <linux/of.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
#include <linux/of_device.h>
/**
#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)
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;
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)
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 unsigned int mcp23s08_irq_startup(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);
+
+ mcp23s08_irq_unmask(data);
+ return 0;
+}
+
+static void mcp23s08_irq_shutdown(struct irq_data *data)
+{
+ struct mcp23s08 *mcp = irq_data_get_irq_chip_data(data);
+
+ mcp23s08_irq_mask(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_startup = mcp23s08_irq_startup,
+ .irq_shutdown = mcp23s08_irq_shutdown,
+};
+
+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
/*----------------------------------------------------------------------*/
static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev,
- void *data, unsigned addr,
- unsigned type, unsigned base, unsigned pullups)
+ void *data, unsigned addr, unsigned type,
+ unsigned base, unsigned pullups)
{
int status;
+ bool mirror = false;
mutex_init(&mcp->lock);
}
mcp->chip.base = base;
- mcp->chip.can_sleep = 1;
+ 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;
- if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN)) {
+
+ 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;
}
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",
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");
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)
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);
match = of_match_device(of_match_ptr(mcp23s08_spi_of_match), &spi->dev);
if (match) {
- type = (int)match->data;
+ type = (int)(uintptr_t)match->data;
status = of_property_read_u32(spi->dev.of_node,
"microchip,spi-present-mask", &spi_present_mask);
if (status) {
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