of: Always use 'struct device.of_node' to get device node pointer.
[safe/jmp/linux-2.6] / drivers / gpio / pca953x.c
index 5a99e81..1db114b 100644 (file)
 
 #include <linux/module.h>
 #include <linux/init.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <linux/i2c.h>
 #include <linux/i2c/pca953x.h>
-
-#include <asm/gpio.h>
+#include <linux/slab.h>
+#ifdef CONFIG_OF_GPIO
+#include <linux/of_platform.h>
+#include <linux/of_gpio.h>
+#endif
 
 #define PCA953X_INPUT          0
 #define PCA953X_OUTPUT         1
 #define PCA953X_INVERT         2
 #define PCA953X_DIRECTION      3
 
+#define PCA953X_GPIOS         0x00FF
+#define PCA953X_INT           0x0100
+
 static const struct i2c_device_id pca953x_id[] = {
-       { "pca9534", 8, },
-       { "pca9535", 16, },
+       { "pca9534", 8  | PCA953X_INT, },
+       { "pca9535", 16 | PCA953X_INT, },
        { "pca9536", 4, },
-       { "pca9537", 4, },
-       { "pca9538", 8, },
-       { "pca9539", 16, },
-       /* REVISIT several pca955x parts should work here too */
+       { "pca9537", 4  | PCA953X_INT, },
+       { "pca9538", 8  | PCA953X_INT, },
+       { "pca9539", 16 | PCA953X_INT, },
+       { "pca9554", 8  | PCA953X_INT, },
+       { "pca9555", 16 | PCA953X_INT, },
+       { "pca9556", 8, },
+       { "pca9557", 8, },
+
+       { "max7310", 8, },
+       { "max7312", 16 | PCA953X_INT, },
+       { "max7313", 16 | PCA953X_INT, },
+       { "max7315", 8  | PCA953X_INT, },
+       { "pca6107", 8  | PCA953X_INT, },
+       { "tca6408", 8  | PCA953X_INT, },
+       { "tca6416", 16 | PCA953X_INT, },
+       /* NYET:  { "tca6424", 24, }, */
        { }
 };
 MODULE_DEVICE_TABLE(i2c, pca953x_id);
@@ -40,13 +61,21 @@ struct pca953x_chip {
        uint16_t reg_output;
        uint16_t reg_direction;
 
+#ifdef CONFIG_GPIO_PCA953X_IRQ
+       struct mutex irq_lock;
+       uint16_t irq_mask;
+       uint16_t irq_stat;
+       uint16_t irq_trig_raise;
+       uint16_t irq_trig_fall;
+       int      irq_base;
+#endif
+
        struct i2c_client *client;
+       struct pca953x_platform_data *dyn_pdata;
        struct gpio_chip gpio_chip;
+       char **names;
 };
 
-/* NOTE:  we can't currently rely on fault codes to come from SMBus
- * calls, so we map all errors to EIO here and return zero otherwise.
- */
 static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val)
 {
        int ret;
@@ -58,7 +87,7 @@ static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val)
 
        if (ret < 0) {
                dev_err(&chip->client->dev, "failed writing register\n");
-               return -EIO;
+               return ret;
        }
 
        return 0;
@@ -75,7 +104,7 @@ static int pca953x_read_reg(struct pca953x_chip *chip, int reg, uint16_t *val)
 
        if (ret < 0) {
                dev_err(&chip->client->dev, "failed reading register\n");
-               return -EIO;
+               return ret;
        }
 
        *val = (uint16_t)ret;
@@ -185,32 +214,300 @@ static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
        gc->base = chip->gpio_start;
        gc->ngpio = gpios;
        gc->label = chip->client->name;
+       gc->dev = &chip->client->dev;
        gc->owner = THIS_MODULE;
+       gc->names = chip->names;
+}
+
+#ifdef CONFIG_GPIO_PCA953X_IRQ
+static int pca953x_gpio_to_irq(struct gpio_chip *gc, unsigned off)
+{
+       struct pca953x_chip *chip;
+
+       chip = container_of(gc, struct pca953x_chip, gpio_chip);
+       return chip->irq_base + off;
+}
+
+static void pca953x_irq_mask(unsigned int irq)
+{
+       struct pca953x_chip *chip = get_irq_chip_data(irq);
+
+       chip->irq_mask &= ~(1 << (irq - chip->irq_base));
+}
+
+static void pca953x_irq_unmask(unsigned int irq)
+{
+       struct pca953x_chip *chip = get_irq_chip_data(irq);
+
+       chip->irq_mask |= 1 << (irq - chip->irq_base);
+}
+
+static void pca953x_irq_bus_lock(unsigned int irq)
+{
+       struct pca953x_chip *chip = get_irq_chip_data(irq);
+
+       mutex_lock(&chip->irq_lock);
+}
+
+static void pca953x_irq_bus_sync_unlock(unsigned int irq)
+{
+       struct pca953x_chip *chip = get_irq_chip_data(irq);
+
+       mutex_unlock(&chip->irq_lock);
+}
+
+static int pca953x_irq_set_type(unsigned int irq, unsigned int type)
+{
+       struct pca953x_chip *chip = get_irq_chip_data(irq);
+       uint16_t level = irq - chip->irq_base;
+       uint16_t mask = 1 << level;
+
+       if (!(type & IRQ_TYPE_EDGE_BOTH)) {
+               dev_err(&chip->client->dev, "irq %d: unsupported type %d\n",
+                       irq, type);
+               return -EINVAL;
+       }
+
+       if (type & IRQ_TYPE_EDGE_FALLING)
+               chip->irq_trig_fall |= mask;
+       else
+               chip->irq_trig_fall &= ~mask;
+
+       if (type & IRQ_TYPE_EDGE_RISING)
+               chip->irq_trig_raise |= mask;
+       else
+               chip->irq_trig_raise &= ~mask;
+
+       return pca953x_gpio_direction_input(&chip->gpio_chip, level);
+}
+
+static struct irq_chip pca953x_irq_chip = {
+       .name                   = "pca953x",
+       .mask                   = pca953x_irq_mask,
+       .unmask                 = pca953x_irq_unmask,
+       .bus_lock               = pca953x_irq_bus_lock,
+       .bus_sync_unlock        = pca953x_irq_bus_sync_unlock,
+       .set_type               = pca953x_irq_set_type,
+};
+
+static uint16_t pca953x_irq_pending(struct pca953x_chip *chip)
+{
+       uint16_t cur_stat;
+       uint16_t old_stat;
+       uint16_t pending;
+       uint16_t trigger;
+       int ret;
+
+       ret = pca953x_read_reg(chip, PCA953X_INPUT, &cur_stat);
+       if (ret)
+               return 0;
+
+       /* Remove output pins from the equation */
+       cur_stat &= chip->reg_direction;
+
+       old_stat = chip->irq_stat;
+       trigger = (cur_stat ^ old_stat) & chip->irq_mask;
+
+       if (!trigger)
+               return 0;
+
+       chip->irq_stat = cur_stat;
+
+       pending = (old_stat & chip->irq_trig_fall) |
+                 (cur_stat & chip->irq_trig_raise);
+       pending &= trigger;
+
+       return pending;
+}
+
+static irqreturn_t pca953x_irq_handler(int irq, void *devid)
+{
+       struct pca953x_chip *chip = devid;
+       uint16_t pending;
+       uint16_t level;
+
+       pending = pca953x_irq_pending(chip);
+
+       if (!pending)
+               return IRQ_HANDLED;
+
+       do {
+               level = __ffs(pending);
+               handle_nested_irq(level + chip->irq_base);
+
+               pending &= ~(1 << level);
+       } while (pending);
+
+       return IRQ_HANDLED;
+}
+
+static int pca953x_irq_setup(struct pca953x_chip *chip,
+                            const struct i2c_device_id *id)
+{
+       struct i2c_client *client = chip->client;
+       struct pca953x_platform_data *pdata = client->dev.platform_data;
+       int ret;
+
+       if (pdata->irq_base && (id->driver_data & PCA953X_INT)) {
+               int lvl;
+
+               ret = pca953x_read_reg(chip, PCA953X_INPUT,
+                                      &chip->irq_stat);
+               if (ret)
+                       goto out_failed;
+
+               /*
+                * There is no way to know which GPIO line generated the
+                * interrupt.  We have to rely on the previous read for
+                * this purpose.
+                */
+               chip->irq_stat &= chip->reg_direction;
+               chip->irq_base = pdata->irq_base;
+               mutex_init(&chip->irq_lock);
+
+               for (lvl = 0; lvl < chip->gpio_chip.ngpio; lvl++) {
+                       int irq = lvl + chip->irq_base;
+
+                       set_irq_chip_data(irq, chip);
+                       set_irq_chip_and_handler(irq, &pca953x_irq_chip,
+                                                handle_edge_irq);
+                       set_irq_nested_thread(irq, 1);
+#ifdef CONFIG_ARM
+                       set_irq_flags(irq, IRQF_VALID);
+#else
+                       set_irq_noprobe(irq);
+#endif
+               }
+
+               ret = request_threaded_irq(client->irq,
+                                          NULL,
+                                          pca953x_irq_handler,
+                                          IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+                                          dev_name(&client->dev), chip);
+               if (ret) {
+                       dev_err(&client->dev, "failed to request irq %d\n",
+                               client->irq);
+                       goto out_failed;
+               }
+
+               chip->gpio_chip.to_irq = pca953x_gpio_to_irq;
+       }
+
+       return 0;
+
+out_failed:
+       chip->irq_base = 0;
+       return ret;
+}
+
+static void pca953x_irq_teardown(struct pca953x_chip *chip)
+{
+       if (chip->irq_base)
+               free_irq(chip->client->irq, chip);
+}
+#else /* CONFIG_GPIO_PCA953X_IRQ */
+static int pca953x_irq_setup(struct pca953x_chip *chip,
+                            const struct i2c_device_id *id)
+{
+       struct i2c_client *client = chip->client;
+       struct pca953x_platform_data *pdata = client->dev.platform_data;
+
+       if (pdata->irq_base && (id->driver_data & PCA953X_INT))
+               dev_warn(&client->dev, "interrupt support not compiled in\n");
+
+       return 0;
+}
+
+static void pca953x_irq_teardown(struct pca953x_chip *chip)
+{
+}
+#endif
+
+/*
+ * Handlers for alternative sources of platform_data
+ */
+#ifdef CONFIG_OF_GPIO
+/*
+ * Translate OpenFirmware node properties into platform_data
+ */
+static struct pca953x_platform_data *
+pca953x_get_alt_pdata(struct i2c_client *client)
+{
+       struct pca953x_platform_data *pdata;
+       struct device_node *node;
+       const uint16_t *val;
+
+       node = client->dev.of_node;
+       if (node == NULL)
+               return NULL;
+
+       pdata = kzalloc(sizeof(struct pca953x_platform_data), GFP_KERNEL);
+       if (pdata == NULL) {
+               dev_err(&client->dev, "Unable to allocate platform_data\n");
+               return NULL;
+       }
+
+       pdata->gpio_base = -1;
+       val = of_get_property(node, "linux,gpio-base", NULL);
+       if (val) {
+               if (*val < 0)
+                       dev_warn(&client->dev,
+                                "invalid gpio-base in device tree\n");
+               else
+                       pdata->gpio_base = *val;
+       }
+
+       val = of_get_property(node, "polarity", NULL);
+       if (val)
+               pdata->invert = *val;
+
+       return pdata;
 }
+#else
+static struct pca953x_platform_data *
+pca953x_get_alt_pdata(struct i2c_client *client)
+{
+       return NULL;
+}
+#endif
 
 static int __devinit pca953x_probe(struct i2c_client *client,
                                   const struct i2c_device_id *id)
 {
        struct pca953x_platform_data *pdata;
        struct pca953x_chip *chip;
-       int ret, i;
-
-       pdata = client->dev.platform_data;
-       if (pdata == NULL)
-               return -ENODEV;
+       int ret;
 
        chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL);
        if (chip == NULL)
                return -ENOMEM;
 
+       pdata = client->dev.platform_data;
+       if (pdata == NULL) {
+               pdata = pca953x_get_alt_pdata(client);
+               /*
+                * Unlike normal platform_data, this is allocated
+                * dynamically and must be freed in the driver
+                */
+               chip->dyn_pdata = pdata;
+       }
+
+       if (pdata == NULL) {
+               dev_dbg(&client->dev, "no platform data\n");
+               ret = -EINVAL;
+               goto out_failed;
+       }
+
        chip->client = client;
 
        chip->gpio_start = pdata->gpio_base;
 
+       chip->names = pdata->names;
+
        /* initialize cached registers from their original values.
         * we can't share this chip with another i2c master.
         */
-       pca953x_setup_gpio(chip, id->driver_data);
+       pca953x_setup_gpio(chip, id->driver_data & PCA953X_GPIOS);
 
        ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output);
        if (ret)
@@ -225,6 +522,9 @@ static int __devinit pca953x_probe(struct i2c_client *client,
        if (ret)
                goto out_failed;
 
+       ret = pca953x_irq_setup(chip, id);
+       if (ret)
+               goto out_failed;
 
        ret = gpiochip_add(&chip->gpio_chip);
        if (ret)
@@ -241,6 +541,8 @@ static int __devinit pca953x_probe(struct i2c_client *client,
        return 0;
 
 out_failed:
+       pca953x_irq_teardown(chip);
+       kfree(chip->dyn_pdata);
        kfree(chip);
        return ret;
 }
@@ -268,6 +570,8 @@ static int pca953x_remove(struct i2c_client *client)
                return ret;
        }
 
+       pca953x_irq_teardown(chip);
+       kfree(chip->dyn_pdata);
        kfree(chip);
        return 0;
 }
@@ -285,7 +589,10 @@ static int __init pca953x_init(void)
 {
        return i2c_add_driver(&pca953x_driver);
 }
-module_init(pca953x_init);
+/* register after i2c postcore initcall and before
+ * subsys initcalls that may rely on these GPIOs
+ */
+subsys_initcall(pca953x_init);
 
 static void __exit pca953x_exit(void)
 {