pca953x: pca953x driver fixes for x86 mrst

Our Moorestown platform has two max7315 chips which is covered by pca953x
i2c gpio driver.

A while ago this driver got updated with nested irq thread support, and it
broke the compatibity with "request_irq".  For example, the gpio_keys.c
driver can not work with this driver now.  This patch fixes the issue by
switching to generic_handle_irq.

Also fix the irq_base issue: irq_base == 0 is valid, and a "-1" value
should mean invalid. IRQ 0 is not a valid IRQ, irq_base of 0 is valid.

Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 6 deletions

diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
index a2b12aa1f2b9..501866662e05 100644
--- a/drivers/gpio/pca953x.c
+++ b/drivers/gpio/pca953x.c
@@ -345,7 +345,7 @@ static irqreturn_t pca953x_irq_handler(int irq, void *devid)
 
         do {
                 level = __ffs(pending);
-                handle_nested_irq(level + chip->irq_base);
+                generic_handle_irq(level + chip->irq_base);
 
                 pending &= ~(1 << level);
         } while (pending);
@@ -360,7 +360,8 @@ static int pca953x_irq_setup(struct pca953x_chip *chip,
         struct pca953x_platform_data *pdata = client->dev.platform_data;
         int ret;
 
-        if (pdata->irq_base && (id->driver_data & PCA953X_INT)) {
+        if (pdata->irq_base != -1
+                        && (id->driver_data & PCA953X_INT)) {
                 int lvl;
 
                 ret = pca953x_read_reg(chip, PCA953X_INPUT,
@@ -383,7 +384,6 @@ static int pca953x_irq_setup(struct pca953x_chip *chip,
                         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
@@ -394,6 +394,7 @@ static int pca953x_irq_setup(struct pca953x_chip *chip,
                 ret = request_threaded_irq(client->irq,
                                            NULL,
                                            pca953x_irq_handler,
+                                           IRQF_TRIGGER_RISING |
                                            IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
                                            dev_name(&client->dev), chip);
                 if (ret) {
@@ -408,13 +409,13 @@ static int pca953x_irq_setup(struct pca953x_chip *chip,
         return 0;
 
 out_failed:
-        chip->irq_base = 0;
+        chip->irq_base = -1;
         return ret;
 }
 
 static void pca953x_irq_teardown(struct pca953x_chip *chip)
 {
-        if (chip->irq_base)
+        if (chip->irq_base != -1)
                 free_irq(chip->client->irq, chip);
 }
 #else /* CONFIG_GPIO_PCA953X_IRQ */
@@ -424,7 +425,7 @@ static int pca953x_irq_setup(struct pca953x_chip *chip,
         struct i2c_client *client = chip->client;
         struct pca953x_platform_data *pdata = client->dev.platform_data;
 
-        if (pdata->irq_base && (id->driver_data & PCA953X_INT))
+        if (pdata->irq_base != -1 && (id->driver_data & PCA953X_INT))
                 dev_warn(&client->dev, "interrupt support not compiled in\n");
 
         return 0;