Merge tag 'gpio-v5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO fixes from Linus Walleij:
 "Some late GPIO fixes for the v5.9 series:

   - Fix compiler warnings on the OMAP when PM is disabled

   - Clear the interrupt when setting edge sensitivity on the Spreadtrum
     driver.

   - Fix up spurious interrupts on the TC35894.

   - Support threaded interrupts on the Siox controller.

   - Fix resource leaks on the mockup driver.

   - Fix line event handling in syscall compatible mode for the
     character device.

   - Fix an unitialized variable in the PCA953A driver.

   - Fix access to all GPIO IRQs on the Aspeed AST2600.

   - Fix line direction on the AMD FCH driver.

   - Use the bitmap API instead of compiler intrinsics for bit
     manipulation in the PCA953x driver"

* tag 'gpio-v5.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: pca953x: Correctly initialize registers 6 and 7 for PCA957x
  gpio: pca953x: Use bitmap API over implicit GCC extension
  gpio: amd-fch: correct logic of GPIO_LINE_DIRECTION
  gpio: aspeed: fix ast2600 bank properties
  gpio/aspeed-sgpio: don't enable all interrupts by default
  gpio/aspeed-sgpio: enable access to all 80 input & output sgpios
  gpio: pca953x: Fix uninitialized pending variable
  gpiolib: Fix line event handling in syscall compatible mode
  gpio: mockup: fix resource leak in error path
  gpio: siox: explicitly support only threaded irqs
  gpio: tc35894: fix up tc35894 interrupt configuration
  gpio: sprd: Clear interrupt when setting the type as edge
  gpio: omap: Fix warnings if PM is disabled

1 files changed, 30 insertions, 4 deletions

diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index e6c9b78adfc2..76c36b05aef6 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -423,6 +423,21 @@ static __poll_t lineevent_poll(struct file *file,
 	return events;
 }
 
+static ssize_t lineevent_get_size(void)
+{
+#ifdef __x86_64__
+	/* i386 has no padding after 'id' */
+	if (in_ia32_syscall()) {
+		struct compat_gpioeevent_data {
+			compat_u64	timestamp;
+			u32		id;
+		};
+
+		return sizeof(struct compat_gpioeevent_data);
+	}
+#endif
+	return sizeof(struct gpioevent_data);
+}
 
 static ssize_t lineevent_read(struct file *file,
 			      char __user *buf,
@@ -432,9 +447,20 @@ static ssize_t lineevent_read(struct file *file,
 	struct lineevent_state *le = file->private_data;
 	struct gpioevent_data ge;
 	ssize_t bytes_read = 0;
+	ssize_t ge_size;
 	int ret;
 
-	if (count < sizeof(ge))
+	/*
+	 * When compatible system call is being used the struct gpioevent_data,
+	 * in case of at least ia32, has different size due to the alignment
+	 * differences. Because we have first member 64 bits followed by one of
+	 * 32 bits there is no gap between them. The only difference is the
+	 * padding at the end of the data structure. Hence, we calculate the
+	 * actual sizeof() and pass this as an argument to copy_to_user() to
+	 * drop unneeded bytes from the output.
+	 */
+	ge_size = lineevent_get_size();
+	if (count < ge_size)
 		return -EINVAL;
 
 	do {
@@ -470,10 +496,10 @@ static ssize_t lineevent_read(struct file *file,
 			break;
 		}
 
-		if (copy_to_user(buf + bytes_read, &ge, sizeof(ge)))
+		if (copy_to_user(buf + bytes_read, &ge, ge_size))
 			return -EFAULT;
-		bytes_read += sizeof(ge);
-	} while (count >= bytes_read + sizeof(ge));
+		bytes_read += ge_size;
+	} while (count >= bytes_read + ge_size);
 
 	return bytes_read;
 }