Merge tag 'gpio-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO changes from Linus Walleij:
 "So this is the LW GPIO patch stack for v3.7:
   - refactoring from Thierry Redding at Arnd Bergmann's request to use
     the seq_file iterator interface in gpiolib.
   - A new driver for Avionic Design's N-bit GPIO expander.
   - Two instances of mutexes replaced by spinlocks from Axel Lin to
     code that is supposed to be fastpath compliant.
   - IRQ demuxer and gpio_to_irq() support for pcf857x by Kuninori
     Morimoto.
   - Dynamic GPIO numbers, device tree support, daisy chaining and some
     other fixes for the 74x164 driver by Maxime Ripard.
   - IRQ domain and device tree support for the tc3589x driver by Lee
     Jones.
   - Some conversion to use managed resources devm_* code.
   - Some instances of clk_prepare() or clk_prepare_enable() added to
     support the new, stricter common clock framework.
   - Some for_each_set_bit() simplifications.
   - Then a lot of fixes as we fixed up all of the above tripping over
     our own shoelaces and that kind of thing."

* tag 'gpio-for-v3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (34 commits)
  gpio: pcf857x: select IRQ_DOMAIN
  gpio: Document device_node's det_debounce
  gpio-lpc32xx: Add GPI_28
  gpio: adnp: dt: Reference generic interrupt binding
  gpio: Add Avionic Design N-bit GPIO expander support
  gpio: pxa: using for_each_set_bit to simplify the code
  gpio_msm: using for_each_set_bit to simplify the code
  gpio: Enable the tc3298x GPIO expander driver for Device Tree
  gpio: Provide the tc3589x GPIO expander driver with an IRQ domain
  ARM: shmobile: kzm9g: use gpio-keys instead of gpio-keys-polled
  gpio: pcf857x: fixup smatch WARNING
  gpio: 74x164: Add support for the daisy-chaining
  gpio: 74x164: dts: Add documentation for the dt binding
  dt: Fix incorrect reference in gpio-led documentation
  gpio: 74x164: Add device tree support
  gpio: 74x164: Use dynamic gpio number assignment if no pdata is present
  gpio: 74x164: Use devm_kzalloc
  gpio: 74x164: Use module_spi_driver boiler plate function
  gpio: sx150x: Use irq_data_get_irq_chip_data() at appropriate places
  gpio: em: Use irq_data_get_irq_chip_data() at appropriate places
  ...

1 files changed, 122 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-pcf857x.c b/drivers/gpio/gpio-pcf857x.c
index 076e236d0da7..16af35cd2b10 100644
--- a/drivers/gpio/gpio-pcf857x.c
+++ b/drivers/gpio/gpio-pcf857x.c
@@ -23,7 +23,12 @@
 #include <linux/gpio.h>
 #include <linux/i2c.h>
 #include <linux/i2c/pcf857x.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
 
 
 static const struct i2c_device_id pcf857x_id[] = {
@@ -60,7 +65,12 @@ struct pcf857x {
 	struct gpio_chip	chip;
 	struct i2c_client	*client;
 	struct mutex		lock;		/* protect 'out' */
+	struct work_struct	work;		/* irq demux work */
+	struct irq_domain	*irq_domain;	/* for irq demux  */
+	spinlock_t		slock;		/* protect irq demux */
 	unsigned		out;		/* software latch */
+	unsigned		status;		/* current status */
+	int			irq;		/* real irq number */
 
 	int (*write)(struct i2c_client *client, unsigned data);
 	int (*read)(struct i2c_client *client);
@@ -150,6 +160,100 @@ static void pcf857x_set(struct gpio_chip *chip, unsigned offset, int value)
 
 /*-------------------------------------------------------------------------*/
 
+static int pcf857x_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+	struct pcf857x *gpio = container_of(chip, struct pcf857x, chip);
+
+	return irq_create_mapping(gpio->irq_domain, offset);
+}
+
+static void pcf857x_irq_demux_work(struct work_struct *work)
+{
+	struct pcf857x *gpio = container_of(work,
+					       struct pcf857x,
+					       work);
+	unsigned long change, i, status, flags;
+
+	status = gpio->read(gpio->client);
+
+	spin_lock_irqsave(&gpio->slock, flags);
+
+	change = gpio->status ^ status;
+	for_each_set_bit(i, &change, gpio->chip.ngpio)
+		generic_handle_irq(irq_find_mapping(gpio->irq_domain, i));
+	gpio->status = status;
+
+	spin_unlock_irqrestore(&gpio->slock, flags);
+}
+
+static irqreturn_t pcf857x_irq_demux(int irq, void *data)
+{
+	struct pcf857x	*gpio = data;
+
+	/*
+	 * pcf857x can't read/write data here,
+	 * since i2c data access might go to sleep.
+	 */
+	schedule_work(&gpio->work);
+
+	return IRQ_HANDLED;
+}
+
+static int pcf857x_irq_domain_map(struct irq_domain *domain, unsigned int virq,
+				 irq_hw_number_t hw)
+{
+	irq_set_chip_and_handler(virq,
+				 &dummy_irq_chip,
+				 handle_level_irq);
+	return 0;
+}
+
+static struct irq_domain_ops pcf857x_irq_domain_ops = {
+	.map	= pcf857x_irq_domain_map,
+};
+
+static void pcf857x_irq_domain_cleanup(struct pcf857x *gpio)
+{
+	if (gpio->irq_domain)
+		irq_domain_remove(gpio->irq_domain);
+
+	if (gpio->irq)
+		free_irq(gpio->irq, gpio);
+}
+
+static int pcf857x_irq_domain_init(struct pcf857x *gpio,
+				   struct pcf857x_platform_data *pdata,
+				   struct device *dev)
+{
+	int status;
+
+	gpio->irq_domain = irq_domain_add_linear(dev->of_node,
+						 gpio->chip.ngpio,
+						 &pcf857x_irq_domain_ops,
+						 NULL);
+	if (!gpio->irq_domain)
+		goto fail;
+
+	/* enable real irq */
+	status = request_irq(pdata->irq, pcf857x_irq_demux, 0,
+			     dev_name(dev), gpio);
+	if (status)
+		goto fail;
+
+	/* enable gpio_to_irq() */
+	INIT_WORK(&gpio->work, pcf857x_irq_demux_work);
+	gpio->chip.to_irq	= pcf857x_to_irq;
+	gpio->irq		= pdata->irq;
+
+	return 0;
+
+fail:
+	pcf857x_irq_domain_cleanup(gpio);
+	return -EINVAL;
+}
+
+/*-------------------------------------------------------------------------*/
+
 static int pcf857x_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
@@ -168,6 +272,7 @@ static int pcf857x_probe(struct i2c_client *client,
 		return -ENOMEM;
 
 	mutex_init(&gpio->lock);
+	spin_lock_init(&gpio->slock);
 
 	gpio->chip.base			= pdata ? pdata->gpio_base : -1;
 	gpio->chip.can_sleep		= 1;
@@ -179,6 +284,15 @@ static int pcf857x_probe(struct i2c_client *client,
 	gpio->chip.direction_output	= pcf857x_output;
 	gpio->chip.ngpio		= id->driver_data;
 
+	/* enable gpio_to_irq() if platform has settings */
+	if (pdata && pdata->irq) {
+		status = pcf857x_irq_domain_init(gpio, pdata, &client->dev);
+		if (status < 0) {
+			dev_err(&client->dev, "irq_domain init failed\n");
+			goto fail;
+		}
+	}
+
 	/* NOTE:  the OnSemi jlc1562b is also largely compatible with
 	 * these parts, notably for output.  It has a low-resolution
 	 * DAC instead of pin change IRQs; and its inputs can be the
@@ -248,6 +362,7 @@ static int pcf857x_probe(struct i2c_client *client,
 	 * all-ones reset state.  Otherwise it flags pins to be driven low.
 	 */
 	gpio->out = pdata ? ~pdata->n_latch : ~0;
+	gpio->status = gpio->out;
 
 	status = gpiochip_add(&gpio->chip);
 	if (status < 0)
@@ -278,6 +393,10 @@ static int pcf857x_probe(struct i2c_client *client,
 fail:
 	dev_dbg(&client->dev, "probe error %d for '%s'\n",
 			status, client->name);
+
+	if (pdata && pdata->irq)
+		pcf857x_irq_domain_cleanup(gpio);
+
 	kfree(gpio);
 	return status;
 }
@@ -299,6 +418,9 @@ static int pcf857x_remove(struct i2c_client *client)
 		}
 	}
 
+	if (pdata && pdata->irq)
+		pcf857x_irq_domain_cleanup(gpio);
+
 	status = gpiochip_remove(&gpio->chip);
 	if (status == 0)
 		kfree(gpio);