[U-Boot] [PATCH 9/9 v2] Exynos: pwm: Use generic api to get pwm clk freq
Minkyu Kang
mk7.kang at samsung.com
Thu Mar 28 06:52:50 CET 2013
On 28/02/13 19:59, Akshay Saraswat wrote:
> Use generic api to get the pwm clock frequency
>
> Test with command "sf probe 1:0; time sf read 40008000 0 1000".
> Try with different numbers of bytes and see that sane values are obtained
> Build and boot U-boot with this patch, backlight works properly.
>
> Signed-off-by: Padmavathi Venna <padma.v at samsung.com>
> Signed-off-by: Akshay Saraswat <akshay.s at samsung.com>
> ---
> Changes since v1:
> - Restored get_pwm_clk call in case of non-exynos5 cpu.
>
> arch/arm/cpu/armv7/s5p-common/pwm.c | 17 ++++++++++++++---
> 1 file changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/cpu/armv7/s5p-common/pwm.c b/arch/arm/cpu/armv7/s5p-common/pwm.c
> index 6f401b8..f5e9a95 100644
> --- a/arch/arm/cpu/armv7/s5p-common/pwm.c
> +++ b/arch/arm/cpu/armv7/s5p-common/pwm.c
> @@ -28,6 +28,7 @@
> #include <asm/io.h>
> #include <asm/arch/pwm.h>
> #include <asm/arch/clk.h>
> +#include <asm/arch/periph.h>
>
> int pwm_enable(int pwm_id)
> {
> @@ -60,7 +61,10 @@ static unsigned long pwm_calc_tin(int pwm_id, unsigned long freq)
> unsigned long tin_parent_rate;
> unsigned int div;
>
> - tin_parent_rate = get_pwm_clk();
> + if (cpu_is_exynos5())
> + tin_parent_rate = clock_get_periph_rate(PERIPH_ID_PWM0);
> + else
> + tin_parent_rate = get_pwm_clk();
>
> for (div = 2; div <= 16; div *= 2) {
> if ((tin_parent_rate / (div << 16)) < freq)
> @@ -165,8 +169,15 @@ int pwm_init(int pwm_id, int div, int invert)
> ticks_per_period = -1UL;
> } else {
> const unsigned long pwm_hz = 1000;
> - unsigned long timer_rate_hz = get_pwm_clk() /
> - ((prescaler + 1) * (1 << div));
> + unsigned long timer_rate_hz;
> +
> + if (cpu_is_exynos5()) {
> + timer_rate_hz = clock_get_periph_rate(PERIPH_ID_PWM0)
> + / ((prescaler + 1) * (1 << div));
> + } else {
> + timer_rate_hz = get_pwm_clk() /
> + ((prescaler + 1) * (1 << div));
> + }
>
> ticks_per_period = timer_rate_hz / pwm_hz;
> }
>
How about this?
diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
index 956427c..a6051b0 100644
--- a/arch/arm/cpu/armv7/exynos/clock.c
+++ b/arch/arm/cpu/armv7/exynos/clock.c
@@ -1210,7 +1210,7 @@ unsigned long get_i2c_clk(void)
unsigned long get_pwm_clk(void)
{
if (cpu_is_exynos5())
- return exynos5_get_pwm_clk();
+ return clock_get_periph_rate(PERIPH_ID_PWM0);
else {
if (proid_is_exynos4412())
return exynos4x12_get_pwm_clk();
When we implement generic clock function for exynos4 then,
we can use clock_get_periph_rate instead of get_pwm_clk.
Thanks,
Minkyu Kang.
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