[PATCH v2] gpio: adp5588-gpio: support interrupt controller
From: Mike Frysinger
Date: Tue Oct 19 2010 - 16:35:28 EST
From: Michael Hennerich <michael.hennerich@xxxxxxxxxx>
This patch implements irq_chip functionality on ADP5588/5587 GPIO
expanders. Only level sensitive interrupts are supported.
Interrupts provided by this irq_chip must be requested using
request_threaded_irq().
Signed-off-by: Michael Hennerich <michael.hennerich@xxxxxxxxxx>
Signed-off-by: Mike Frysinger <vapier@xxxxxxxxxx>
---
v2
- update feedback from akpm
drivers/gpio/Kconfig | 7 +
drivers/gpio/adp5588-gpio.c | 277 +++++++++++++++++++++++++++++++++++++++----
include/linux/i2c/adp5588.h | 15 +++
3 files changed, 278 insertions(+), 21 deletions(-)
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 7face91..cc912d2 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -249,6 +249,13 @@ config GPIO_ADP5588
To compile this driver as a module, choose M here: the module will be
called adp5588-gpio.
+config GPIO_ADP5588_IRQ
+ bool "Interrupt controller support for ADP5588"
+ depends on GPIO_ADP5588=y
+ help
+ Say yes here to enable the adp5588 to be used as an interrupt
+ controller. It requires the driver to be built in the kernel.
+
comment "PCI GPIO expanders:"
config GPIO_CS5535
diff --git a/drivers/gpio/adp5588-gpio.c b/drivers/gpio/adp5588-gpio.c
index 2e8e9e2..0871f78 100644
--- a/drivers/gpio/adp5588-gpio.c
+++ b/drivers/gpio/adp5588-gpio.c
@@ -1,8 +1,8 @@
/*
* GPIO Chip driver for Analog Devices
- * ADP5588 I/O Expander and QWERTY Keypad Controller
+ * ADP5588/ADP5587 I/O Expander and QWERTY Keypad Controller
*
- * Copyright 2009 Analog Devices Inc.
+ * Copyright 2009-2010 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
@@ -13,21 +13,34 @@
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
#include <linux/i2c/adp5588.h>
-#define DRV_NAME "adp5588-gpio"
-#define MAXGPIO 18
-#define ADP_BANK(offs) ((offs) >> 3)
-#define ADP_BIT(offs) (1u << ((offs) & 0x7))
+#define DRV_NAME "adp5588-gpio"
+
+/*
+ * Early pre 4.0 Silicon required to delay readout by at least 25ms,
+ * since the Event Counter Register updated 25ms after the interrupt
+ * asserted.
+ */
+#define WA_DELAYED_READOUT_REVID(rev) ((rev) < 4)
struct adp5588_gpio {
struct i2c_client *client;
struct gpio_chip gpio_chip;
struct mutex lock; /* protect cached dir, dat_out */
+ /* protect serialized access to the interrupt controller bus */
+ struct mutex irq_lock;
unsigned gpio_start;
+ unsigned irq_base;
uint8_t dat_out[3];
uint8_t dir[3];
+ uint8_t int_lvl[3];
+ uint8_t int_en[3];
+ uint8_t irq_mask[3];
+ uint8_t irq_stat[3];
};
static int adp5588_gpio_read(struct i2c_client *client, u8 reg)
@@ -55,8 +68,8 @@ static int adp5588_gpio_get_value(struct gpio_chip *chip, unsigned off)
struct adp5588_gpio *dev =
container_of(chip, struct adp5588_gpio, gpio_chip);
- return !!(adp5588_gpio_read(dev->client, GPIO_DAT_STAT1 + ADP_BANK(off))
- & ADP_BIT(off));
+ return !!(adp5588_gpio_read(dev->client,
+ GPIO_DAT_STAT1 + ADP5588_BANK(off)) & ADP5588_BIT(off));
}
static void adp5588_gpio_set_value(struct gpio_chip *chip,
@@ -66,8 +79,8 @@ static void adp5588_gpio_set_value(struct gpio_chip *chip,
struct adp5588_gpio *dev =
container_of(chip, struct adp5588_gpio, gpio_chip);
- bank = ADP_BANK(off);
- bit = ADP_BIT(off);
+ bank = ADP5588_BANK(off);
+ bit = ADP5588_BIT(off);
mutex_lock(&dev->lock);
if (val)
@@ -87,10 +100,10 @@ static int adp5588_gpio_direction_input(struct gpio_chip *chip, unsigned off)
struct adp5588_gpio *dev =
container_of(chip, struct adp5588_gpio, gpio_chip);
- bank = ADP_BANK(off);
+ bank = ADP5588_BANK(off);
mutex_lock(&dev->lock);
- dev->dir[bank] &= ~ADP_BIT(off);
+ dev->dir[bank] &= ~ADP5588_BIT(off);
ret = adp5588_gpio_write(dev->client, GPIO_DIR1 + bank, dev->dir[bank]);
mutex_unlock(&dev->lock);
@@ -105,8 +118,8 @@ static int adp5588_gpio_direction_output(struct gpio_chip *chip,
struct adp5588_gpio *dev =
container_of(chip, struct adp5588_gpio, gpio_chip);
- bank = ADP_BANK(off);
- bit = ADP_BIT(off);
+ bank = ADP5588_BANK(off);
+ bit = ADP5588_BIT(off);
mutex_lock(&dev->lock);
dev->dir[bank] |= bit;
@@ -125,6 +138,213 @@ static int adp5588_gpio_direction_output(struct gpio_chip *chip,
return ret;
}
+#ifdef CONFIG_GPIO_ADP5588_IRQ
+static int adp5588_gpio_to_irq(struct gpio_chip *chip, unsigned off)
+{
+ struct adp5588_gpio *dev =
+ container_of(chip, struct adp5588_gpio, gpio_chip);
+ return dev->irq_base + off;
+}
+
+static void adp5588_irq_bus_lock(unsigned int irq)
+{
+ struct adp5588_gpio *dev = get_irq_chip_data(irq);
+ mutex_lock(&dev->irq_lock);
+}
+
+ /*
+ * genirq core code can issue chip->mask/unmask from atomic context.
+ * This doesn't work for slow busses where an access needs to sleep.
+ * bus_sync_unlock() is therefore called outside the atomic context,
+ * syncs the current irq mask state with the slow external controller
+ * and unlocks the bus.
+ */
+
+static void adp5588_irq_bus_sync_unlock(unsigned int irq)
+{
+ struct adp5588_gpio *dev = get_irq_chip_data(irq);
+ int i;
+
+ for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++)
+ if (dev->int_en[i] ^ dev->irq_mask[i]) {
+ dev->int_en[i] = dev->irq_mask[i];
+ adp5588_gpio_write(dev->client, GPIO_INT_EN1 + i,
+ dev->int_en[i]);
+ }
+
+ mutex_unlock(&dev->irq_lock);
+}
+
+static void adp5588_irq_mask(unsigned int irq)
+{
+ struct adp5588_gpio *dev = get_irq_chip_data(irq);
+ unsigned gpio = irq - dev->irq_base;
+
+ dev->irq_mask[ADP5588_BANK(gpio)] &= ~ADP5588_BIT(gpio);
+}
+
+static void adp5588_irq_unmask(unsigned int irq)
+{
+ struct adp5588_gpio *dev = get_irq_chip_data(irq);
+ unsigned gpio = irq - dev->irq_base;
+
+ dev->irq_mask[ADP5588_BANK(gpio)] |= ADP5588_BIT(gpio);
+}
+
+static int adp5588_irq_set_type(unsigned int irq, unsigned int type)
+{
+ struct adp5588_gpio *dev = get_irq_chip_data(irq);
+ uint16_t gpio = irq - dev->irq_base;
+ unsigned bank, bit;
+
+ if ((type & IRQ_TYPE_EDGE_BOTH)) {
+ dev_err(&dev->client->dev, "irq %d: unsupported type %d\n",
+ irq, type);
+ return -EINVAL;
+ }
+
+ bank = ADP5588_BANK(gpio);
+ bit = ADP5588_BIT(gpio);
+
+ if (type & IRQ_TYPE_LEVEL_HIGH)
+ dev->int_lvl[bank] |= bit;
+ else if (type & IRQ_TYPE_LEVEL_LOW)
+ dev->int_lvl[bank] &= ~bit;
+ else
+ return -EINVAL;
+
+ adp5588_gpio_direction_input(&dev->gpio_chip, gpio);
+ adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + bank,
+ dev->int_lvl[bank]);
+
+ return 0;
+}
+
+static struct irq_chip adp5588_irq_chip = {
+ .name = "adp5588",
+ .mask = adp5588_irq_mask,
+ .unmask = adp5588_irq_unmask,
+ .bus_lock = adp5588_irq_bus_lock,
+ .bus_sync_unlock = adp5588_irq_bus_sync_unlock,
+ .set_type = adp5588_irq_set_type,
+};
+
+static int adp5588_gpio_read_intstat(struct i2c_client *client, u8 *buf)
+{
+ int ret = i2c_smbus_read_i2c_block_data(client, GPIO_INT_STAT1, 3, buf);
+
+ if (ret < 0)
+ dev_err(&client->dev, "Read INT_STAT Error\n");
+
+ return ret;
+}
+
+static irqreturn_t adp5588_irq_handler(int irq, void *devid)
+{
+ struct adp5588_gpio *dev = devid;
+ unsigned status, bank, bit, pending;
+ int ret;
+ status = adp5588_gpio_read(dev->client, INT_STAT);
+
+ if (status & ADP5588_GPI_INT) {
+ ret = adp5588_gpio_read_intstat(dev->client, dev->irq_stat);
+ if (ret < 0)
+ memset(dev->irq_stat, 0, ARRAY_SIZE(dev->irq_stat));
+
+ for (bank = 0; bank <= ADP5588_BANK(ADP5588_MAXGPIO);
+ bank++, bit = 0) {
+ pending = dev->irq_stat[bank] & dev->irq_mask[bank];
+
+ while (pending) {
+ if (pending & (1 << bit)) {
+ handle_nested_irq(dev->irq_base +
+ (bank << 3) + bit);
+ pending &= ~(1 << bit);
+
+ }
+ bit++;
+ }
+ }
+ }
+
+ adp5588_gpio_write(dev->client, INT_STAT, status); /* Status is W1C */
+
+ return IRQ_HANDLED;
+}
+
+static int adp5588_irq_setup(struct adp5588_gpio *dev)
+{
+ struct i2c_client *client = dev->client;
+ struct adp5588_gpio_platform_data *pdata = client->dev.platform_data;
+ unsigned gpio;
+ int ret;
+
+ adp5588_gpio_write(client, CFG, ADP5588_AUTO_INC);
+ adp5588_gpio_write(client, INT_STAT, -1); /* status is W1C */
+ adp5588_gpio_read_intstat(client, dev->irq_stat); /* read to clear */
+
+ dev->irq_base = pdata->irq_base;
+ mutex_init(&dev->irq_lock);
+
+ for (gpio = 0; gpio < dev->gpio_chip.ngpio; gpio++) {
+ int irq = gpio + dev->irq_base;
+ set_irq_chip_data(irq, dev);
+ set_irq_chip_and_handler(irq, &adp5588_irq_chip,
+ handle_level_irq);
+ set_irq_nested_thread(irq, 1);
+#ifdef CONFIG_ARM
+ /*
+ * ARM needs us to explicitly flag the IRQ as VALID,
+ * once we do so, it will also set the noprobe.
+ */
+ set_irq_flags(irq, IRQF_VALID);
+#else
+ set_irq_noprobe(irq);
+#endif
+ }
+
+ ret = request_threaded_irq(client->irq,
+ NULL,
+ adp5588_irq_handler,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ dev_name(&client->dev), dev);
+ if (ret) {
+ dev_err(&client->dev, "failed to request irq %d\n",
+ client->irq);
+ goto out;
+ }
+
+ dev->gpio_chip.to_irq = adp5588_gpio_to_irq;
+ adp5588_gpio_write(client, CFG,
+ ADP5588_AUTO_INC | ADP5588_INT_CFG | ADP5588_GPI_INT);
+
+ return 0;
+
+out:
+ dev->irq_base = 0;
+ return ret;
+}
+
+static void adp5588_irq_teardown(struct adp5588_gpio *dev)
+{
+ if (dev->irq_base)
+ free_irq(dev->client->irq, dev);
+}
+
+#else
+static int adp5588_irq_setup(struct adp5588_gpio *dev)
+{
+ struct i2c_client *client = dev->client;
+ dev_warn(&client->dev, "interrupt support not compiled in\n");
+
+ return 0;
+}
+
+static void adp5588_irq_teardown(struct adp5588_gpio *dev)
+{
+}
+#endif /* CONFIG_GPIO_ADP5588_IRQ */
+
static int __devinit adp5588_gpio_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -160,37 +380,46 @@ static int __devinit adp5588_gpio_probe(struct i2c_client *client,
gc->can_sleep = 1;
gc->base = pdata->gpio_start;
- gc->ngpio = MAXGPIO;
+ gc->ngpio = ADP5588_MAXGPIO;
gc->label = client->name;
gc->owner = THIS_MODULE;
mutex_init(&dev->lock);
-
ret = adp5588_gpio_read(dev->client, DEV_ID);
if (ret < 0)
goto err;
revid = ret & ADP5588_DEVICE_ID_MASK;
- for (i = 0, ret = 0; i <= ADP_BANK(MAXGPIO); i++) {
+ for (i = 0, ret = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) {
dev->dat_out[i] = adp5588_gpio_read(client, GPIO_DAT_OUT1 + i);
dev->dir[i] = adp5588_gpio_read(client, GPIO_DIR1 + i);
ret |= adp5588_gpio_write(client, KP_GPIO1 + i, 0);
ret |= adp5588_gpio_write(client, GPIO_PULL1 + i,
(pdata->pullup_dis_mask >> (8 * i)) & 0xFF);
-
+ ret |= adp5588_gpio_write(client, GPIO_INT_EN1 + i, 0);
if (ret)
goto err;
}
+ if (pdata->irq_base) {
+ if (WA_DELAYED_READOUT_REVID(revid)) {
+ dev_warn(&client->dev, "GPIO int not supported\n");
+ } else {
+ ret = adp5588_irq_setup(dev);
+ if (ret)
+ goto err;
+ }
+ }
+
ret = gpiochip_add(&dev->gpio_chip);
if (ret)
- goto err;
+ goto err_irq;
- dev_info(&client->dev, "gpios %d..%d on a %s Rev. %d\n",
+ dev_info(&client->dev, "gpios %d..%d (IRQ Base %d) on a %s Rev. %d\n",
gc->base, gc->base + gc->ngpio - 1,
- client->name, revid);
+ pdata->irq_base, client->name, revid);
if (pdata->setup) {
ret = pdata->setup(client, gc->base, gc->ngpio, pdata->context);
@@ -199,8 +428,11 @@ static int __devinit adp5588_gpio_probe(struct i2c_client *client,
}
i2c_set_clientdata(client, dev);
+
return 0;
+err_irq:
+ adp5588_irq_teardown(dev);
err:
kfree(dev);
return ret;
@@ -222,6 +454,9 @@ static int __devexit adp5588_gpio_remove(struct i2c_client *client)
}
}
+ if (dev->irq_base)
+ free_irq(dev->client->irq, dev);
+
ret = gpiochip_remove(&dev->gpio_chip);
if (ret) {
dev_err(&client->dev, "gpiochip_remove failed %d\n", ret);
diff --git a/include/linux/i2c/adp5588.h b/include/linux/i2c/adp5588.h
index b02ff58..32dde3e 100644
--- a/include/linux/i2c/adp5588.h
+++ b/include/linux/i2c/adp5588.h
@@ -74,6 +74,20 @@
#define ADP5588_DEVICE_ID_MASK 0xF
+ /* Configuration Register1 */
+#define ADP5588_AUTO_INC (1 << 7)
+#define ADP5588_GPIEM_CFG (1 << 6)
+#define ADP5588_INT_CFG (1 << 4)
+#define ADP5588_GPI_IEN (1 << 1)
+
+/* Interrupt Status Register */
+#define ADP5588_GPI_INT (1 << 1)
+#define ADP5588_KE_INT (1 << 0)
+
+#define ADP5588_MAXGPIO 18
+#define ADP5588_BANK(offs) ((offs) >> 3)
+#define ADP5588_BIT(offs) (1u << ((offs) & 0x7))
+
/* Put one of these structures in i2c_board_info platform_data */
#define ADP5588_KEYMAPSIZE 80
@@ -129,6 +143,7 @@ struct i2c_client; /* forward declaration */
struct adp5588_gpio_platform_data {
unsigned gpio_start; /* GPIO Chip base # */
+ unsigned irq_base; /* interrupt base # */
unsigned pullup_dis_mask; /* Pull-Up Disable Mask */
int (*setup)(struct i2c_client *client,
int gpio, unsigned ngpio,
--
1.7.3.1
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