Messages in this thread Patch in this message | | | From | Guru Das Srinagesh <> | Subject | [PATCH v7 06/13] pwm: pwm-imx-tpm: Use 64-bit division macros for period and duty cycle | Date | Mon, 9 Mar 2020 12:35:09 -0700 |
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Because period and duty cycle are defined in the PWM framework structs as ints with units of nanoseconds, the maximum time duration that can be set is limited to ~2.147 seconds. Redefining them as u64 values will enable larger time durations to be set.
As a first step, prepare drivers to handle the switch to u64 period and duty_cycle by replacing division operations involving pwm period and duty cycle with their 64-bit equivalents as appropriate. The actual switch to u64 period and duty_cycle follows as a separate patch.
Where the dividend is 64-bit but the divisor is 32-bit, use *_ULL macros: - DIV_ROUND_UP_ULL - DIV_ROUND_CLOSEST_ULL - div_u64
Where the divisor is 64-bit (dividend may be 32-bit or 64-bit), use DIV64_* macros: - DIV64_U64_ROUND_CLOSEST - div64_u64
Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Pengutronix Kernel Team <kernel@pengutronix.de> Cc: Fabio Estevam <festevam@gmail.com> Cc: NXP Linux Team <linux-imx@nxp.com>
Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org> --- drivers/pwm/pwm-imx-tpm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/pwm/pwm-imx-tpm.c b/drivers/pwm/pwm-imx-tpm.c index 9145f61..53bf364 100644 --- a/drivers/pwm/pwm-imx-tpm.c +++ b/drivers/pwm/pwm-imx-tpm.c @@ -126,7 +126,7 @@ static int pwm_imx_tpm_round_state(struct pwm_chip *chip, real_state->duty_cycle = state->duty_cycle; tmp = (u64)p->mod * real_state->duty_cycle; - p->val = DIV_ROUND_CLOSEST_ULL(tmp, real_state->period); + p->val = DIV64_U64_ROUND_CLOSEST(tmp, real_state->period); real_state->polarity = state->polarity; real_state->enabled = state->enabled; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
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