Merge tag 'iio-for-4.8b' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Second round of new iio device support, features and cleanups in the 4.8 cycle

Firstly some contact detail updates:
* NXP took over freescale. Update the mma8452 header to reflect this.
* Martin Kepplinger email address change in mma8452 header.
* Adriana Reus has changed email address. Update .mailmap.
* Matt Ranostay has changed email address. Update .mailmap.

New Device Support
* max1363
  - add the missing i2c_device_ids for a couple of parts so they can actually
    be used.
* ms5867
  - add device ids for ms5805 and ms5837 parts.

New Features
* ad5755
  - DT support.  This one was a bit controversial and under review for a long
    time.  Still no one could come up with a better solution.
* stx104
  - add gpio support
* ti-adc081c
  - Add ACPI device ID matching.

Core changes
* Refuse to register triggers with duplicate names.  There is no way to
  distinguish between them so this makes no sense.  A few drivers do not
  generate unique names for each instance of the device present.  We can't
  fix this without changing ABI so leave them and wait for someone to
  actually take the rare step of two identical accelerometers on the same
  board.
* buffer-dma
  - use ARRAY_SIZE in a few appropriate locations.

Tools
* Fix the fact that the --trigger-num option in generic_buffer didn't allow
  0 which is perfectly valid in the ABI.

Cleanups
* as3935
  - improve error reporting.
  - remove redundant zeroing of a field in iio_priv.
* gp2ap020a00f
  - use the iio_device_claim_*_mode helpers rather than open coding locking
  around mode changes.
* isl29125
  - use the iio_device_claim_*_mode helpers rather than open coding locking.
* lidar
  - use the iio_device_claim_*_mode helpers rather than open coding locking.
* mma8452
  - more detail in devices supported description in comments (addresses and
  similar)
* sca3000
  - add a missing error check.
* tcs3414
  - use the iio_device_claim_*_mode helpers rather than open coding locking.
* tcs3472
  - use the iio_device_claim_*_mode helpers rather than open coding locking.

1 files changed, 123 insertions, 2 deletions

diff --git a/drivers/iio/dac/stx104.c b/drivers/iio/dac/stx104.c
index 27941220872f..792a97164cb2 100644
--- a/drivers/iio/dac/stx104.c
+++ b/drivers/iio/dac/stx104.c
@@ -14,6 +14,7 @@
 #include <linux/bitops.h>
 #include <linux/device.h>
 #include <linux/errno.h>
+#include <linux/gpio/driver.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/types.h>
 #include <linux/io.h>
@@ -21,6 +22,7 @@
 #include <linux/isa.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/spinlock.h>
 
 #define STX104_NUM_CHAN 2
 
@@ -49,6 +51,20 @@ struct stx104_iio {
 	unsigned base;
 };
 
+/**
+ * struct stx104_gpio - GPIO device private data structure
+ * @chip:	instance of the gpio_chip
+ * @lock:	synchronization lock to prevent I/O race conditions
+ * @base:	base port address of the GPIO device
+ * @out_state:	output bits state
+ */
+struct stx104_gpio {
+	struct gpio_chip chip;
+	spinlock_t lock;
+	unsigned int base;
+	unsigned int out_state;
+};
+
 static int stx104_read_raw(struct iio_dev *indio_dev,
 	struct iio_chan_spec const *chan, int *val, int *val2, long mask)
 {
@@ -88,15 +104,81 @@ static const struct iio_chan_spec stx104_channels[STX104_NUM_CHAN] = {
 	STX104_CHAN(1)
 };
 
+static int stx104_gpio_get_direction(struct gpio_chip *chip,
+	unsigned int offset)
+{
+	if (offset < 4)
+		return 1;
+
+	return 0;
+}
+
+static int stx104_gpio_direction_input(struct gpio_chip *chip,
+	unsigned int offset)
+{
+	if (offset >= 4)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int stx104_gpio_direction_output(struct gpio_chip *chip,
+	unsigned int offset, int value)
+{
+	if (offset < 4)
+		return -EINVAL;
+
+	chip->set(chip, offset, value);
+	return 0;
+}
+
+static int stx104_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+	struct stx104_gpio *const stx104gpio = gpiochip_get_data(chip);
+
+	if (offset >= 4)
+		return -EINVAL;
+
+	return !!(inb(stx104gpio->base) & BIT(offset));
+}
+
+static void stx104_gpio_set(struct gpio_chip *chip, unsigned int offset,
+	int value)
+{
+	struct stx104_gpio *const stx104gpio = gpiochip_get_data(chip);
+	const unsigned int mask = BIT(offset) >> 4;
+	unsigned long flags;
+
+	if (offset < 4)
+		return;
+
+	spin_lock_irqsave(&stx104gpio->lock, flags);
+
+	if (value)
+		stx104gpio->out_state |= mask;
+	else
+		stx104gpio->out_state &= ~mask;
+
+	outb(stx104gpio->out_state, stx104gpio->base);
+
+	spin_unlock_irqrestore(&stx104gpio->lock, flags);
+}
+
 static int stx104_probe(struct device *dev, unsigned int id)
 {
 	struct iio_dev *indio_dev;
 	struct stx104_iio *priv;
+	struct stx104_gpio *stx104gpio;
+	int err;
 
 	indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
 	if (!indio_dev)
 		return -ENOMEM;
 
+	stx104gpio = devm_kzalloc(dev, sizeof(*stx104gpio), GFP_KERNEL);
+	if (!stx104gpio)
+		return -ENOMEM;
+
 	if (!devm_request_region(dev, base[id], STX104_EXTENT,
 		dev_name(dev))) {
 		dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
@@ -117,14 +199,53 @@ static int stx104_probe(struct device *dev, unsigned int id)
 	outw(0, base[id] + 4);
 	outw(0, base[id] + 6);
 
-	return devm_iio_device_register(dev, indio_dev);
+	err = devm_iio_device_register(dev, indio_dev);
+	if (err) {
+		dev_err(dev, "IIO device registering failed (%d)\n", err);
+		return err;
+	}
+
+	stx104gpio->chip.label = dev_name(dev);
+	stx104gpio->chip.parent = dev;
+	stx104gpio->chip.owner = THIS_MODULE;
+	stx104gpio->chip.base = -1;
+	stx104gpio->chip.ngpio = 8;
+	stx104gpio->chip.get_direction = stx104_gpio_get_direction;
+	stx104gpio->chip.direction_input = stx104_gpio_direction_input;
+	stx104gpio->chip.direction_output = stx104_gpio_direction_output;
+	stx104gpio->chip.get = stx104_gpio_get;
+	stx104gpio->chip.set = stx104_gpio_set;
+	stx104gpio->base = base[id] + 3;
+	stx104gpio->out_state = 0x0;
+
+	spin_lock_init(&stx104gpio->lock);
+
+	dev_set_drvdata(dev, stx104gpio);
+
+	err = gpiochip_add_data(&stx104gpio->chip, stx104gpio);
+	if (err) {
+		dev_err(dev, "GPIO registering failed (%d)\n", err);
+		return err;
+	}
+
+	return 0;
+}
+
+static int stx104_remove(struct device *dev, unsigned int id)
+{
+	struct stx104_gpio *const stx104gpio = dev_get_drvdata(dev);
+
+	gpiochip_remove(&stx104gpio->chip);
+
+	return 0;
 }
 
 static struct isa_driver stx104_driver = {
 	.probe = stx104_probe,
 	.driver = {
 		.name = "stx104"
-	}
+	},
+	.remove = stx104_remove
 };
 
 module_isa_driver(stx104_driver, num_stx104);