From 348fb6f7fb4cc7ebc35d1cde6e5c2ada64b683c6 Mon Sep 17 00:00:00 2001 From: Lokesh Vutla Date: Thu, 12 Mar 2020 09:52:07 +0530 Subject: pwm: omap-dmtimer: Update description for PWM OMAP DM timer MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Update the description with a brief about how PWM is generated using OMAP DM timer and add limitations for the PWM generations. Also add a link to the reference manual. Suggested-by: Uwe Kleine-König Acked-by: Tony Lindgren Signed-off-by: Lokesh Vutla Acked-by: Uwe Kleine-König Signed-off-by: Thierry Reding --- drivers/pwm/pwm-omap-dmtimer.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'drivers/pwm') diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c index e4f5f710bfaa..92aac6c86b95 100644 --- a/drivers/pwm/pwm-omap-dmtimer.c +++ b/drivers/pwm/pwm-omap-dmtimer.c @@ -10,7 +10,15 @@ * * Description: * This file is the core OMAP support for the generic, Linux - * PWM driver / controller, using the OMAP's dual-mode timers. + * PWM driver / controller, using the OMAP's dual-mode timers + * with a timer counter that goes up. When it overflows it gets + * reloaded with the load value and the pwm output goes up. + * When counter matches with match register, the output goes down. + * Reference Manual: http://www.ti.com/lit/ug/spruh73q/spruh73q.pdf + * + * Limitations: + * - When PWM is stopped, timer counter gets stopped immediately. This + * doesn't allow the current PWM period to complete and stops abruptly. */ #include -- cgit v1.2.3