releases/4.14.69/pwm-tiehrpwm-fix-disabling-of-output-of-pwms.patch

   1 From 38dabd91ff0bde33352ca3cc65ef515599b77a05 Mon Sep 17 00:00:00 2001
   2 From: Vignesh R <vigneshr@ti.com>
   3 Date: Mon, 11 Jun 2018 11:39:56 +0530
   4 Subject: pwm: tiehrpwm: Fix disabling of output of PWMs
   5
   6 From: Vignesh R <vigneshr@ti.com>
   7
   8 commit 38dabd91ff0bde33352ca3cc65ef515599b77a05 upstream.
   9
  10 pwm-tiehrpwm driver disables PWM output by putting it in low output
  11 state via active AQCSFRC register in ehrpwm_pwm_disable(). But, the
  12 AQCSFRC shadow register is not updated. Therefore, when shadow AQCSFRC
  13 register is re-enabled in ehrpwm_pwm_enable() (say to enable second PWM
  14 output), previous settings are lost as shadow register value is loaded
  15 into active register. This results in things like PWMA getting enabled
  16 automatically, when PWMB is enabled and vice versa. Fix this by
  17 updating AQCSFRC shadow register as well during ehrpwm_pwm_disable().
  18
  19 Fixes: 19891b20e7c2 ("pwm: pwm-tiehrpwm: PWM driver support for EHRPWM")
  20 Cc: stable@vger.kernel.org
  21 Signed-off-by: Vignesh R <vigneshr@ti.com>
  22 Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
  23 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  24
  25 ---
  26  drivers/pwm/pwm-tiehrpwm.c |    2 ++
  27  1 file changed, 2 insertions(+)
  28
  29 --- a/drivers/pwm/pwm-tiehrpwm.c
  30 +++ b/drivers/pwm/pwm-tiehrpwm.c
  31 @@ -381,6 +381,8 @@ static void ehrpwm_pwm_disable(struct pw
  32                 aqcsfrc_mask = AQCSFRC_CSFA_MASK;
  33         }
  34
  35 +       /* Update shadow register first before modifying active register */
  36 +       ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
  37         /*
  38          * Changes to immediate action on Action Qualifier. This puts
  39          * Action Qualifier control on PWM output from next TBCLK