From 39c1e3aba23b308e871501f4a105a1ccd7cb495d Mon Sep 17 00:00:00 2001
From: Pierre-noel Bouteville <pn_bouteville@yahoo.fr>
Date: Mon, 30 May 2016 11:58:22 -0600
Subject: [PATCH] Allow to not use all channet in a lower part of PWM

---
 arch/arm/src/stm32/stm32_pwm.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/arm/src/stm32/stm32_pwm.c b/arch/arm/src/stm32/stm32_pwm.c
index 8779d18692..76783804ea 100644
--- a/arch/arm/src/stm32/stm32_pwm.c
+++ b/arch/arm/src/stm32/stm32_pwm.c
@@ -1314,6 +1314,15 @@ static int pwm_timer(FAR struct stm32_pwmtimer_s *priv,
       duty = info->channels[i].duty;
       channel = info->channels[i].channel;
 
+      /* A value of zero means to skip this channel */
+
+      if (channel == 0)
+        {
+          continue;
+        }
+
+      /* Find the channel */
+
       for (j = 0; j < PWM_NCHANNELS; j++)
         {
           if (priv->channels[j].channel == channel)