| 92809eee | 28-Mar-2013 |
Gabe Black <gabeblack@google.com> |
Exynos: Tidy up the pwm_config function in the exynos pwm driver
Some small fixes in the exynos pwm driver:
1. NS_IN_HZ is non-sensical since these are not compatible units. This constant actually
Exynos: Tidy up the pwm_config function in the exynos pwm driver
Some small fixes in the exynos pwm driver:
1. NS_IN_HZ is non-sensical since these are not compatible units. This constant actually describes the number of nanoseconds in a second. Renamed it to NS_IN_SEC. Also dropped the unnecessary parenthesis. 2. The variable "period" is not used to hold a period, it's used to hold a frequency. Renamed it to "frequency". 3. tcmp is an unsigned value, so (tcmp < 0) will never be true and the if which checks that condition will never execute. Also, there should be no problem if the pwm never switches, so there's no reason to subtract one from tcmp and therefore no reason to compare it against zero. Removed both ifs. If they weren't removed, tcmp should be a signed value. 4. Add a check for a 0 period.
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: Gabe Black <gabeblack@google.com> Signed-off-by: Akshay Saraswat <akshay.s@samsung.com> Acked-by: Simon Glass <sjg@chromium.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
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| 34b5ee1f | 28-Mar-2013 |
Gabe Black <gabeblack@google.com> |
Exynos: Avoid a divide by zero by specifying a non-zero period for pwm 4
The pwm_config function in the exynos pwm driver divides by its period period parameter. A function was calling pwm_config wi
Exynos: Avoid a divide by zero by specifying a non-zero period for pwm 4
The pwm_config function in the exynos pwm driver divides by its period period parameter. A function was calling pwm_config with a 0ns period and a 0ns duty cycle. That doesn't actually make any sense physically, and results in a divide by zero in the driver. This change changes the parameters to be a 100000ns period and duty cycle.
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: Gabe Black <gabeblack@google.com> Signed-off-by: Akshay Saraswat <akshay.s@samsung.com> Acked-by: Simon Glass <sjg@chromium.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
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| c059f274 | 28-Mar-2013 |
Gabe Black <gabeblack@google.com> |
Exynos: pwm: Fix two bugs in the exynos pwm configuration code
First, the "div" value was being used incorrectly to compute the frequency of the PWM timer. The value passed in is a constant which re
Exynos: pwm: Fix two bugs in the exynos pwm configuration code
First, the "div" value was being used incorrectly to compute the frequency of the PWM timer. The value passed in is a constant which reflects the value that would be found in a configuration register, 0 to 4. That should correspond to a scaling factor of 1, 2, 4, 8, or 16, 1 << div, but div + 1 was being used instead.
Second, the reset value of the timers were being calculated to give an overall frequency, thrown out, and set to a maximum value. This was done so that PWM 4 could be used as the system clock by counting down from a high value, but it was applied indiscriminantly. It should at most be applied only to PWM 4.
This change also takes the opportunity to tidy up the pwm_init function.
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: Gabe Black <gabeblack@google.com> Signed-off-by: Akshay Saraswat <akshay.s@samsung.com> Acked-by: Simon Glass <sjg@chromium.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
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| f24869d3 | 28-Mar-2013 |
Che-Liang Chiou <clchiou@chromium.org> |
Exynos: Add timer_get_us function
timer_get_us returns the time in microseconds since a certain reference point of history. However, it does not guarantee to return an accurate time after a long pe
Exynos: Add timer_get_us function
timer_get_us returns the time in microseconds since a certain reference point of history. However, it does not guarantee to return an accurate time after a long period; instead, it wraps around (that is, the reference point is reset to some other point of history) after some periods. The frequency of wrapping around is about an hour (or 2^32 microseconds).
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
Signed-off-by: Che-Liang Chiou <clchiou@chromium.org> Signed-off-by: Akshay Saraswat <akshay.s@samsung.com> Acked-by: Simon Glass <sjg@chromium.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
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| 5d845f27 | 16-May-2011 |
Minkyu Kang <mk7.kang@samsung.com> |
S5PC2XX: Support the cpu revision
S5PC210 SoC have two cpu revisions, and have some difference. So, support the cpu revision for each revision.
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com> Sig
S5PC2XX: Support the cpu revision
S5PC210 SoC have two cpu revisions, and have some difference. So, support the cpu revision for each revision.
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
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