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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-19 08:19:07 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-19 08:19:07 -0800
commit74779e22261172ea728b989310f6ecc991b57d62 (patch)
treea6c71e02bf6cefc9e0d261dd1ab11f4a7433ed92 /drivers/pwm/pwm-lpc32xx.c
parent5031a2a7c12b837a0913c4139ebeb6bbff5e1aa5 (diff)
parent20e8ac3eea4dcfeea6ebeae57cd2c739fa48da11 (diff)
Merge tag 'for-3.8-rc1' of git://gitorious.org/linux-pwm/linux-pwm
Pull pwm changes from Thierry Reding: "A new driver has been added for the SPEAr platform and the TWL4030/6030 driver has been replaced by two drivers that control the regular PWMs and the PWM driven LEDs provided by the chips. The vt8500, tiecap, tiehrpwm, i.MX, LPC32xx and Samsung drivers have all been improved and the device tree bindings now support the PWM signal polarity." Fix up trivial conflicts due to __devinit/exit removal. * tag 'for-3.8-rc1' of git://gitorious.org/linux-pwm/linux-pwm: (21 commits) pwm: samsung: add missing s3c->pwm_id assignment pwm: lpc32xx: Set the chip base for dynamic allocation pwm: lpc32xx: Properly disable the clock on device removal pwm: lpc32xx: Fix the PWM polarity pwm: i.MX: eliminate build warning pwm: Export of_pwm_xlate_with_flags() pwm: Remove pwm-twl6030 driver pwm: New driver to support PWM driven LEDs on TWL4030/6030 series of PMICs pwm: New driver to support PWMs on TWL4030/6030 series of PMICs pwm: pwm-tiehrpwm: pinctrl support pwm: tiehrpwm: Add device-tree binding pwm: pwm-tiehrpwm: Adding TBCLK gating support. pwm: pwm-tiecap: pinctrl support pwm: tiecap: Add device-tree binding pwm: Add TI PWM subsystem driver pwm: Device tree support for PWM polarity pwm: vt8500: Ensure PWM clock is enabled during pwm_config pwm: vt8500: Fix build error pwm: spear: Staticize spear_pwm_config() pwm: Add SPEAr PWM chip driver support ...
Diffstat (limited to 'drivers/pwm/pwm-lpc32xx.c')
-rw-r--r--drivers/pwm/pwm-lpc32xx.c23
1 files changed, 21 insertions, 2 deletions
diff --git a/drivers/pwm/pwm-lpc32xx.c b/drivers/pwm/pwm-lpc32xx.c
index 015a82235620..14106440294f 100644
--- a/drivers/pwm/pwm-lpc32xx.c
+++ b/drivers/pwm/pwm-lpc32xx.c
@@ -49,9 +49,24 @@ static int lpc32xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
c = 0; /* 0 set division by 256 */
period_cycles = c;
+ /* The duty-cycle value is as follows:
+ *
+ * DUTY-CYCLE HIGH LEVEL
+ * 1 99.9%
+ * 25 90.0%
+ * 128 50.0%
+ * 220 10.0%
+ * 255 0.1%
+ * 0 0.0%
+ *
+ * In other words, the register value is duty-cycle % 256 with
+ * duty-cycle in the range 1-256.
+ */
c = 256 * duty_ns;
do_div(c, period_ns);
- duty_cycles = c;
+ if (c > 255)
+ c = 255;
+ duty_cycles = 256 - c;
writel(PWM_ENABLE | PWM_RELOADV(period_cycles) | PWM_DUTY(duty_cycles),
lpc32xx->base + (pwm->hwpwm << 2));
@@ -106,6 +121,7 @@ static int lpc32xx_pwm_probe(struct platform_device *pdev)
lpc32xx->chip.dev = &pdev->dev;
lpc32xx->chip.ops = &lpc32xx_pwm_ops;
lpc32xx->chip.npwm = 2;
+ lpc32xx->chip.base = -1;
ret = pwmchip_add(&lpc32xx->chip);
if (ret < 0) {
@@ -121,8 +137,11 @@ static int lpc32xx_pwm_probe(struct platform_device *pdev)
static int lpc32xx_pwm_remove(struct platform_device *pdev)
{
struct lpc32xx_pwm_chip *lpc32xx = platform_get_drvdata(pdev);
+ unsigned int i;
+
+ for (i = 0; i < lpc32xx->chip.npwm; i++)
+ pwm_disable(&lpc32xx->chip.pwms[i]);
- clk_disable(lpc32xx->clk);
return pwmchip_remove(&lpc32xx->chip);
}