pwm: Add Renesas TPU PWM driver

The Timer Pulse Unit (TPU) is a 4-channels 16-bit timer used to generate
waveforms. This driver exposes PWM functions through the PWM API for
other drivers to use.

The code is loosely based on the leds-renesas-tpu driver by Magnus Damm
and the TPU PWM driver shipped in the Armadillo EVA 800 kernel sources.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Tested-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
diff --git a/include/linux/platform_data/pwm-renesas-tpu.h b/include/linux/platform_data/pwm-renesas-tpu.h
new file mode 100644
index 0000000..a7220b1
--- /dev/null
+++ b/include/linux/platform_data/pwm-renesas-tpu.h
@@ -0,0 +1,16 @@
+#ifndef __PWM_RENESAS_TPU_H__
+#define __PWM_RENESAS_TPU_H__
+
+#include <linux/pwm.h>
+
+#define TPU_CHANNEL_MAX		4
+
+struct tpu_pwm_channel_data {
+	enum pwm_polarity polarity;
+};
+
+struct tpu_pwm_platform_data {
+	struct tpu_pwm_channel_data channels[TPU_CHANNEL_MAX];
+};
+
+#endif /* __PWM_RENESAS_TPU_H__ */