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

[linux-2.6-microblaze.git] / drivers / iio / dac / stx104.c

diff --git a/drivers/iio/dac/stx104.c b/drivers/iio/dac/stx104.c
index 174f4b7..792a971 100644 (file)
--- 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
 
@@ -33,16 +35,9 @@
 }
 
 #define STX104_EXTENT 16
-/**
- * The highest base address possible for an ISA device is 0x3FF; this results in
- * 1024 possible base addresses. Dividing the number of possible base addresses
- * by the address extent taken by each device results in the maximum number of
- * devices on a system.
- */
-#define MAX_NUM_STX104 (1024 / STX104_EXTENT)
 
-static unsigned base[MAX_NUM_STX104];
-static unsigned num_stx104;
+static unsigned int base[max_num_isa_dev(STX104_EXTENT)];
+static unsigned int num_stx104;
 module_param_array(base, uint, &num_stx104, 0);
 MODULE_PARM_DESC(base, "Apex Embedded Systems STX104 base addresses");
 
@@ -56,6 +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)
 {
@@ -95,15 +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",
@@ -124,28 +199,56 @@ 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;
+       }
 
-static struct isa_driver stx104_driver = {
-       .probe = stx104_probe,
-       .driver = {
-               .name = "stx104"
+       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;
        }
-};
 
-static void __exit stx104_exit(void)
-{
-       isa_unregister_driver(&stx104_driver);
+       return 0;
 }
 
-static int __init stx104_init(void)
+static int stx104_remove(struct device *dev, unsigned int id)
 {
-       return isa_register_driver(&stx104_driver, num_stx104);
+       struct stx104_gpio *const stx104gpio = dev_get_drvdata(dev);
+
+       gpiochip_remove(&stx104gpio->chip);
+
+       return 0;
 }
 
-module_init(stx104_init);
-module_exit(stx104_exit);
+static struct isa_driver stx104_driver = {
+       .probe = stx104_probe,
+       .driver = {
+               .name = "stx104"
+       },
+       .remove = stx104_remove
+};
+
+module_isa_driver(stx104_driver, num_stx104);
 
 MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
 MODULE_DESCRIPTION("Apex Embedded Systems STX104 DAC driver");