1 files changed, 202 insertions, 89 deletions

diff --git a/drivers/gpio/gpio-pcf857x.c b/drivers/gpio/gpio-pcf857x.c
index 2d1de9e7e9b..27b46751ea7 100644
--- a/drivers/gpio/gpio-pcf857x.c
+++ b/drivers/gpio/gpio-pcf857x.c
@@ -18,12 +18,18 @@
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#include <linux/kernel.h>
-#include <linux/slab.h>
 #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/kernel.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
 
 
 static const struct i2c_device_id pcf857x_id[] = {
@@ -40,10 +46,32 @@ static const struct i2c_device_id pcf857x_id[] = {
 	{ "pca9675", 16 },
 	{ "max7328", 8 },
 	{ "max7329", 8 },
+	{ "tca9554", 8 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, pcf857x_id);
 
+#ifdef CONFIG_OF
+static const struct of_device_id pcf857x_of_table[] = {
+	{ .compatible = "nxp,pcf8574" },
+	{ .compatible = "nxp,pcf8574a" },
+	{ .compatible = "nxp,pca8574" },
+	{ .compatible = "nxp,pca9670" },
+	{ .compatible = "nxp,pca9672" },
+	{ .compatible = "nxp,pca9674" },
+	{ .compatible = "nxp,pcf8575" },
+	{ .compatible = "nxp,pca8575" },
+	{ .compatible = "nxp,pca9671" },
+	{ .compatible = "nxp,pca9673" },
+	{ .compatible = "nxp,pca9675" },
+	{ .compatible = "maxim,max7328" },
+	{ .compatible = "maxim,max7329" },
+	{ .compatible = "ti,tca9554" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, pcf857x_of_table);
+#endif
+
 /*
  * The pcf857x, pca857x, and pca967x chips only expose one read and one
  * write register.  Writing a "one" bit (to match the reset state) lets
@@ -60,62 +88,33 @@ struct pcf857x {
 	struct gpio_chip	chip;
 	struct i2c_client	*client;
 	struct mutex		lock;		/* protect 'out' */
+	struct irq_domain	*irq_domain;	/* for irq demux  */
+	spinlock_t		slock;		/* protect irq demux */
 	unsigned		out;		/* software latch */
+	unsigned		status;		/* current status */
+	unsigned		irq_mapped;	/* mapped gpio irqs */
+
+	int (*write)(struct i2c_client *client, unsigned data);
+	int (*read)(struct i2c_client *client);
 };
 
 /*-------------------------------------------------------------------------*/
 
 /* Talk to 8-bit I/O expander */
 
-static int pcf857x_input8(struct gpio_chip *chip, unsigned offset)
+static int i2c_write_le8(struct i2c_client *client, unsigned data)
 {
-	struct pcf857x	*gpio = container_of(chip, struct pcf857x, chip);
-	int		status;
-
-	mutex_lock(&gpio->lock);
-	gpio->out |= (1 << offset);
-	status = i2c_smbus_write_byte(gpio->client, gpio->out);
-	mutex_unlock(&gpio->lock);
-
-	return status;
+	return i2c_smbus_write_byte(client, data);
 }
 
-static int pcf857x_get8(struct gpio_chip *chip, unsigned offset)
+static int i2c_read_le8(struct i2c_client *client)
 {
-	struct pcf857x	*gpio = container_of(chip, struct pcf857x, chip);
-	s32		value;
-
-	value = i2c_smbus_read_byte(gpio->client);
-	return (value < 0) ? 0 : (value & (1 << offset));
+	return (int)i2c_smbus_read_byte(client);
 }
 
-static int pcf857x_output8(struct gpio_chip *chip, unsigned offset, int value)
-{
-	struct pcf857x	*gpio = container_of(chip, struct pcf857x, chip);
-	unsigned	bit = 1 << offset;
-	int		status;
-
-	mutex_lock(&gpio->lock);
-	if (value)
-		gpio->out |= bit;
-	else
-		gpio->out &= ~bit;
-	status = i2c_smbus_write_byte(gpio->client, gpio->out);
-	mutex_unlock(&gpio->lock);
-
-	return status;
-}
-
-static void pcf857x_set8(struct gpio_chip *chip, unsigned offset, int value)
-{
-	pcf857x_output8(chip, offset, value);
-}
-
-/*-------------------------------------------------------------------------*/
-
 /* Talk to 16-bit I/O expander */
 
-static int i2c_write_le16(struct i2c_client *client, u16 word)
+static int i2c_write_le16(struct i2c_client *client, unsigned word)
 {
 	u8 buf[2] = { word & 0xff, word >> 8, };
 	int status;
@@ -135,29 +134,31 @@ static int i2c_read_le16(struct i2c_client *client)
 	return (buf[1] << 8) | buf[0];
 }
 
-static int pcf857x_input16(struct gpio_chip *chip, unsigned offset)
+/*-------------------------------------------------------------------------*/
+
+static int pcf857x_input(struct gpio_chip *chip, unsigned offset)
 {
 	struct pcf857x	*gpio = container_of(chip, struct pcf857x, chip);
 	int		status;
 
 	mutex_lock(&gpio->lock);
 	gpio->out |= (1 << offset);
-	status = i2c_write_le16(gpio->client, gpio->out);
+	status = gpio->write(gpio->client, gpio->out);
 	mutex_unlock(&gpio->lock);
 
 	return status;
 }
 
-static int pcf857x_get16(struct gpio_chip *chip, unsigned offset)
+static int pcf857x_get(struct gpio_chip *chip, unsigned offset)
 {
 	struct pcf857x	*gpio = container_of(chip, struct pcf857x, chip);
 	int		value;
 
-	value = i2c_read_le16(gpio->client);
+	value = gpio->read(gpio->client);
 	return (value < 0) ? 0 : (value & (1 << offset));
 }
 
-static int pcf857x_output16(struct gpio_chip *chip, unsigned offset, int value)
+static int pcf857x_output(struct gpio_chip *chip, unsigned offset, int value)
 {
 	struct pcf857x	*gpio = container_of(chip, struct pcf857x, chip);
 	unsigned	bit = 1 << offset;
@@ -168,15 +169,113 @@ static int pcf857x_output16(struct gpio_chip *chip, unsigned offset, int value)
 		gpio->out |= bit;
 	else
 		gpio->out &= ~bit;
-	status = i2c_write_le16(gpio->client, gpio->out);
+	status = gpio->write(gpio->client, gpio->out);
 	mutex_unlock(&gpio->lock);
 
 	return status;
 }
 
-static void pcf857x_set16(struct gpio_chip *chip, unsigned offset, int value)
+static void pcf857x_set(struct gpio_chip *chip, unsigned offset, int value)
 {
-	pcf857x_output16(chip, offset, value);
+	pcf857x_output(chip, offset, value);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int pcf857x_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+	struct pcf857x *gpio = container_of(chip, struct pcf857x, chip);
+	int ret;
+
+	ret = irq_create_mapping(gpio->irq_domain, offset);
+	if (ret > 0)
+		gpio->irq_mapped |= (1 << offset);
+
+	return ret;
+}
+
+static irqreturn_t pcf857x_irq(int irq, void *data)
+{
+	struct pcf857x  *gpio = data;
+	unsigned long change, i, status, flags;
+
+	status = gpio->read(gpio->client);
+
+	spin_lock_irqsave(&gpio->slock, flags);
+
+	/*
+	 * call the interrupt handler iff gpio is used as
+	 * interrupt source, just to avoid bad irqs
+	 */
+
+	change = ((gpio->status ^ status) & gpio->irq_mapped);
+	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);
+
+	return IRQ_HANDLED;
+}
+
+static int pcf857x_irq_domain_map(struct irq_domain *domain, unsigned int irq,
+				 irq_hw_number_t hw)
+{
+	struct pcf857x *gpio = domain->host_data;
+
+	irq_set_chip_and_handler(irq,
+				 &dummy_irq_chip,
+				 handle_level_irq);
+#ifdef CONFIG_ARM
+	set_irq_flags(irq, IRQF_VALID);
+#else
+	irq_set_noprobe(irq);
+#endif
+	gpio->irq_mapped |= (1 << hw);
+
+	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);
+
+}
+
+static int pcf857x_irq_domain_init(struct pcf857x *gpio,
+				   struct i2c_client *client)
+{
+	int status;
+
+	gpio->irq_domain = irq_domain_add_linear(client->dev.of_node,
+						 gpio->chip.ngpio,
+						 &pcf857x_irq_domain_ops,
+						 gpio);
+	if (!gpio->irq_domain)
+		goto fail;
+
+	/* enable real irq */
+	status = devm_request_threaded_irq(&client->dev, client->irq,
+				NULL, pcf857x_irq, IRQF_ONESHOT |
+				IRQF_TRIGGER_FALLING | IRQF_SHARED,
+				dev_name(&client->dev), gpio);
+
+	if (status)
+		goto fail;
+
+	/* enable gpio_to_irq() */
+	gpio->chip.to_irq	= pcf857x_to_irq;
+
+	return 0;
+
+fail:
+	pcf857x_irq_domain_cleanup(gpio);
+	return -EINVAL;
 }
 
 /*-------------------------------------------------------------------------*/
@@ -184,26 +283,45 @@ static void pcf857x_set16(struct gpio_chip *chip, unsigned offset, int value)
 static int pcf857x_probe(struct i2c_client *client,
 			 const struct i2c_device_id *id)
 {
-	struct pcf857x_platform_data	*pdata;
+	struct pcf857x_platform_data	*pdata = dev_get_platdata(&client->dev);
+	struct device_node		*np = client->dev.of_node;
 	struct pcf857x			*gpio;
+	unsigned int			n_latch = 0;
 	int				status;
 
-	pdata = client->dev.platform_data;
-	if (!pdata) {
+	if (IS_ENABLED(CONFIG_OF) && np)
+		of_property_read_u32(np, "lines-initial-states", &n_latch);
+	else if (pdata)
+		n_latch = pdata->n_latch;
+	else
 		dev_dbg(&client->dev, "no platform data\n");
-	}
 
 	/* Allocate, initialize, and register this gpio_chip. */
-	gpio = kzalloc(sizeof *gpio, GFP_KERNEL);
+	gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL);
 	if (!gpio)
 		return -ENOMEM;
 
 	mutex_init(&gpio->lock);
-
-	gpio->chip.base = pdata ? pdata->gpio_base : -1;
-	gpio->chip.can_sleep = 1;
-	gpio->chip.dev = &client->dev;
-	gpio->chip.owner = THIS_MODULE;
+	spin_lock_init(&gpio->slock);
+
+	gpio->chip.base			= pdata ? pdata->gpio_base : -1;
+	gpio->chip.can_sleep		= true;
+	gpio->chip.dev			= &client->dev;
+	gpio->chip.owner		= THIS_MODULE;
+	gpio->chip.get			= pcf857x_get;
+	gpio->chip.set			= pcf857x_set;
+	gpio->chip.direction_input	= pcf857x_input;
+	gpio->chip.direction_output	= pcf857x_output;
+	gpio->chip.ngpio		= id->driver_data;
+
+	/* enable gpio_to_irq() if platform has settings */
+	if (client->irq) {
+		status = pcf857x_irq_domain_init(gpio, client);
+		if (status < 0) {
+			dev_err(&client->dev, "irq_domain init failed\n");
+			goto fail_irq_domain;
+		}
+	}
 
 	/* NOTE:  the OnSemi jlc1562b is also largely compatible with
 	 * these parts, notably for output.  It has a low-resolution
@@ -216,12 +334,9 @@ static int pcf857x_probe(struct i2c_client *client,
 	 *
 	 * NOTE: we don't distinguish here between *4 and *4a parts.
 	 */
-	gpio->chip.ngpio = id->driver_data;
 	if (gpio->chip.ngpio == 8) {
-		gpio->chip.direction_input = pcf857x_input8;
-		gpio->chip.get = pcf857x_get8;
-		gpio->chip.direction_output = pcf857x_output8;
-		gpio->chip.set = pcf857x_set8;
+		gpio->write	= i2c_write_le8;
+		gpio->read	= i2c_read_le8;
 
 		if (!i2c_check_functionality(client->adapter,
 				I2C_FUNC_SMBUS_BYTE))
@@ -238,10 +353,8 @@ static int pcf857x_probe(struct i2c_client *client,
 	 * NOTE: we don't distinguish here between '75 and '75c parts.
 	 */
 	} else if (gpio->chip.ngpio == 16) {
-		gpio->chip.direction_input = pcf857x_input16;
-		gpio->chip.get = pcf857x_get16;
-		gpio->chip.direction_output = pcf857x_output16;
-		gpio->chip.set = pcf857x_set16;
+		gpio->write	= i2c_write_le16;
+		gpio->read	= i2c_read_le16;
 
 		if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
 			status = -EIO;
@@ -274,25 +387,17 @@ static int pcf857x_probe(struct i2c_client *client,
 	 * may cause transient glitching since it can't know the last value
 	 * written (some pins may need to be driven low).
 	 *
-	 * Using pdata->n_latch avoids that trouble.  When left initialized
-	 * to zero, our software copy of the "latch" then matches the chip's
-	 * all-ones reset state.  Otherwise it flags pins to be driven low.
+	 * Using n_latch avoids that trouble.  When left initialized to zero,
+	 * our software copy of the "latch" then matches the chip's all-ones
+	 * reset state.  Otherwise it flags pins to be driven low.
 	 */
-	gpio->out = pdata ? ~pdata->n_latch : ~0;
+	gpio->out = ~n_latch;
+	gpio->status = gpio->out;
 
 	status = gpiochip_add(&gpio->chip);
 	if (status < 0)
 		goto fail;
 
-	/* NOTE: these chips can issue "some pin-changed" IRQs, which we
-	 * don't yet even try to use.  Among other issues, the relevant
-	 * genirq state isn't available to modular drivers; and most irq
-	 * methods can't be called from sleeping contexts.
-	 */
-
-	dev_info(&client->dev, "%s\n",
-			client->irq ? " (irq ignored)" : "");
-
 	/* Let platform code set up the GPIOs and their users.
 	 * Now is the first time anyone could use them.
 	 */
@@ -304,18 +409,24 @@ static int pcf857x_probe(struct i2c_client *client,
 			dev_warn(&client->dev, "setup --> %d\n", status);
 	}
 
+	dev_info(&client->dev, "probed\n");
+
 	return 0;
 
 fail:
+	if (client->irq)
+		pcf857x_irq_domain_cleanup(gpio);
+
+fail_irq_domain:
 	dev_dbg(&client->dev, "probe error %d for '%s'\n",
-			status, client->name);
-	kfree(gpio);
+		status, client->name);
+
 	return status;
 }
 
 static int pcf857x_remove(struct i2c_client *client)
 {
-	struct pcf857x_platform_data	*pdata = client->dev.platform_data;
+	struct pcf857x_platform_data	*pdata = dev_get_platdata(&client->dev);
 	struct pcf857x			*gpio = i2c_get_clientdata(client);
 	int				status = 0;
 
@@ -330,10 +441,11 @@ static int pcf857x_remove(struct i2c_client *client)
 		}
 	}
 
+	if (client->irq)
+		pcf857x_irq_domain_cleanup(gpio);
+
 	status = gpiochip_remove(&gpio->chip);
-	if (status == 0)
-		kfree(gpio);
-	else
+	if (status)
 		dev_err(&client->dev, "%s --> %d\n", "remove", status);
 	return status;
 }
@@ -342,6 +454,7 @@ static struct i2c_driver pcf857x_driver = {
 	.driver = {
 		.name	= "pcf857x",
 		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(pcf857x_of_table),
 	},
 	.probe	= pcf857x_probe,
 	.remove	= pcf857x_remove,