diff options
Diffstat (limited to 'drivers/gpio/gpio-mcp23s08.c')
| -rw-r--r-- | drivers/gpio/gpio-mcp23s08.c | 291 |
1 files changed, 266 insertions, 25 deletions
diff --git a/drivers/gpio/gpio-mcp23s08.c b/drivers/gpio/gpio-mcp23s08.c index 2deb0c5e54a..57adbc90fda 100644 --- a/drivers/gpio/gpio-mcp23s08.c +++ b/drivers/gpio/gpio-mcp23s08.c @@ -1,5 +1,13 @@ /* - * 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> @@ -12,7 +20,8 @@ #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> /** @@ -34,6 +43,7 @@ #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) @@ -57,8 +67,14 @@ 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; @@ -77,6 +93,11 @@ struct mcp23s08_driver_data { 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) @@ -152,7 +173,7 @@ static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg) tx[0] = mcp->addr | 0x01; tx[1] = reg; - status = spi_write_then_read(mcp->data, tx, sizeof tx, rx, sizeof rx); + status = spi_write_then_read(mcp->data, tx, sizeof(tx), rx, sizeof(rx)); return (status < 0) ? status : rx[0]; } @@ -163,7 +184,7 @@ static int mcp23s08_write(struct mcp23s08 *mcp, unsigned reg, unsigned val) tx[0] = mcp->addr; tx[1] = reg; tx[2] = val; - return spi_write_then_read(mcp->data, tx, sizeof tx, NULL, 0); + return spi_write_then_read(mcp->data, tx, sizeof(tx), NULL, 0); } static int @@ -172,13 +193,13 @@ mcp23s08_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n) u8 tx[2], *tmp; int status; - if ((n + reg) > sizeof mcp->cache) + 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); + status = spi_write_then_read(mcp->data, tx, sizeof(tx), tmp, n); if (status >= 0) { while (n--) vals[n] = tmp[n]; /* expand to 16bit */ @@ -193,7 +214,7 @@ static int mcp23s17_read(struct mcp23s08 *mcp, unsigned reg) tx[0] = mcp->addr | 0x01; tx[1] = reg << 1; - status = spi_write_then_read(mcp->data, tx, sizeof tx, rx, sizeof rx); + status = spi_write_then_read(mcp->data, tx, sizeof(tx), rx, sizeof(rx)); return (status < 0) ? status : (rx[0] | (rx[1] << 8)); } @@ -205,7 +226,7 @@ static int mcp23s17_write(struct mcp23s08 *mcp, unsigned reg, unsigned val) tx[1] = reg << 1; tx[2] = val; tx[3] = val >> 8; - return spi_write_then_read(mcp->data, tx, sizeof tx, NULL, 0); + return spi_write_then_read(mcp->data, tx, sizeof(tx), NULL, 0); } static int @@ -214,12 +235,12 @@ mcp23s17_read_regs(struct mcp23s08 *mcp, unsigned reg, u16 *vals, unsigned n) u8 tx[2]; int status; - if ((n + reg) > sizeof mcp->cache) + 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, + status = spi_write_then_read(mcp->data, tx, sizeof(tx), (u8 *)vals, n * 2); if (status >= 0) { while (n--) @@ -316,6 +337,195 @@ mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value) } /*----------------------------------------------------------------------*/ +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 @@ -357,7 +567,7 @@ static void mcp23s08_dbg_show(struct seq_file *s, struct gpio_chip *chip) (mcp->cache[MCP_GPIO] & mask) ? "hi" : "lo", (mcp->cache[MCP_GPPU] & mask) ? "up" : " "); /* NOTE: ignoring the irq-related registers */ - seq_printf(s, "\n"); + seq_puts(s, "\n"); } done: mutex_unlock(&mcp->lock); @@ -370,10 +580,11 @@ done: /*----------------------------------------------------------------------*/ 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); @@ -425,20 +636,32 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev, } 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; @@ -470,6 +693,16 @@ static int mcp23s08_probe_one(struct mcp23s08 *mcp, struct device *dev, } 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", @@ -481,7 +714,7 @@ fail: #ifdef CONFIG_OF #ifdef CONFIG_SPI_MASTER -static struct of_device_id mcp23s08_spi_of_match[] = { +static const struct of_device_id mcp23s08_spi_of_match[] = { { .compatible = "microchip,mcp23s08", .data = (void *) MCP_TYPE_S08, @@ -505,7 +738,7 @@ MODULE_DEVICE_TABLE(of, mcp23s08_spi_of_match); #endif #if IS_ENABLED(CONFIG_I2C) -static struct of_device_id mcp23s08_i2c_of_match[] = { +static const struct of_device_id mcp23s08_i2c_of_match[] = { { .compatible = "microchip,mcp23008", .data = (void *) MCP_TYPE_008, @@ -546,6 +779,7 @@ static int mcp230xx_probe(struct i2c_client *client, 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"); @@ -555,10 +789,11 @@ static int mcp230xx_probe(struct i2c_client *client, pullups = pdata->chip[0].pullups; } - mcp = kzalloc(sizeof *mcp, GFP_KERNEL); + 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) @@ -579,6 +814,9 @@ 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); @@ -629,7 +867,7 @@ static int mcp23s08_probe(struct spi_device *spi) { struct mcp23s08_platform_data *pdata; unsigned addr; - unsigned chips = 0; + int chips = 0; struct mcp23s08_driver_data *data; int status, type; unsigned base = -1, @@ -640,7 +878,7 @@ static int mcp23s08_probe(struct spi_device *spi) 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) { @@ -657,8 +895,11 @@ static int mcp23s08_probe(struct spi_device *spi) return -ENODEV; } - for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) + for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) { pullups[addr] = 0; + if (spi_present_mask & (1 << addr)) + chips++; + } } else { type = spi_get_device_id(spi)->driver_data; pdata = dev_get_platdata(&spi->dev); @@ -681,13 +922,13 @@ static int mcp23s08_probe(struct spi_device *spi) pullups[addr] = pdata->chip[addr].pullups; } - if (!chips) - return -ENODEV; - base = pdata->base; } - data = kzalloc(sizeof *data + chips * sizeof(struct mcp23s08), + if (!chips) + return -ENODEV; + + data = kzalloc(sizeof(*data) + chips * sizeof(struct mcp23s08), GFP_KERNEL); if (!data) return -ENOMEM; |