ARM: 5628/1: ep93xx: Introduce Pulse Width Modulator (PWM) driver

The EP93xx features two PWMs (one on the EP9307) with the following
features:

  * Configurable dual output
  * Separate input clocks for each PWM output
  * 16-bit resolution
  * Programmable pulse width (duty cycle), interval (frequency), and
    polarity

This adds the necessary core support as well as the driver.  A sysfs
interface is provided to control the PWM outputs.

Signed-off-by: Matthieu Crapet <mcrapet@gmail.com>
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Ryan Mallon <ryan@bluewatersys.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/arm/mach-ep93xx/clock.c b/arch/arm/mach-ep93xx/clock.c
index b6b53447b1b4..3dd0e2a23095 100644
--- a/arch/arm/mach-ep93xx/clock.c
+++ b/arch/arm/mach-ep93xx/clock.c
@@ -72,6 +72,9 @@ static struct clk clk_keypad = {
         .enable_mask    = EP93XX_SYSCON_KEYTCHCLKDIV_KEN,
         .set_rate       = set_keytchclk_rate,
 };
+static struct clk clk_pwm = {
+        .rate           = EP93XX_EXT_CLK_RATE,
+};
 
 /* DMA Clocks */
 static struct clk clk_m2p0 = {
@@ -137,6 +140,7 @@ static struct clk_lookup clocks[] = {
         INIT_CK(NULL,                   "pll2",         &clk_pll2),
         INIT_CK("ep93xx-ohci",          NULL,           &clk_usb_host),
         INIT_CK("ep93xx-keypad",        NULL,           &clk_keypad),
+        INIT_CK(NULL,                   "pwm_clk",      &clk_pwm),
         INIT_CK(NULL,                   "m2p0",         &clk_m2p0),
         INIT_CK(NULL,                   "m2p1",         &clk_m2p1),
         INIT_CK(NULL,                   "m2p2",         &clk_m2p2),