From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: "Sasha Levin" <sashal@kernel.org>,
linux-pwm@vger.kernel.org,
"Thierry Reding" <thierry.reding@gmail.com>,
linux-arm-kernel@lists.infradead.org,
"Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
Subject: [PATCH AUTOSEL 5.7 317/388] pwm: imx27: Fix rounding behavior
Date: Wed, 17 Jun 2020 21:06:54 -0400 [thread overview]
Message-ID: <20200618010805.600873-317-sashal@kernel.org> (raw)
In-Reply-To: <20200618010805.600873-1-sashal@kernel.org>
From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[ Upstream commit aef1a3799b5cb3ba4841f6034497b179646ccc70 ]
To not trigger the warnings provided by CONFIG_PWM_DEBUG
- use up-rounding in .get_state()
- don't divide by the result of a division
- don't use the rounded counter value for the period length to calculate
the counter value for the duty cycle
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pwm/pwm-imx27.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/drivers/pwm/pwm-imx27.c b/drivers/pwm/pwm-imx27.c
index a6e40d4c485f..732a6f3701e8 100644
--- a/drivers/pwm/pwm-imx27.c
+++ b/drivers/pwm/pwm-imx27.c
@@ -150,13 +150,12 @@ static void pwm_imx27_get_state(struct pwm_chip *chip,
prescaler = MX3_PWMCR_PRESCALER_GET(val);
pwm_clk = clk_get_rate(imx->clk_per);
- pwm_clk = DIV_ROUND_CLOSEST_ULL(pwm_clk, prescaler);
val = readl(imx->mmio_base + MX3_PWMPR);
period = val >= MX3_PWMPR_MAX ? MX3_PWMPR_MAX : val;
/* PWMOUT (Hz) = PWMCLK / (PWMPR + 2) */
- tmp = NSEC_PER_SEC * (u64)(period + 2);
- state->period = DIV_ROUND_CLOSEST_ULL(tmp, pwm_clk);
+ tmp = NSEC_PER_SEC * (u64)(period + 2) * prescaler;
+ state->period = DIV_ROUND_UP_ULL(tmp, pwm_clk);
/*
* PWMSAR can be read only if PWM is enabled. If the PWM is disabled,
@@ -167,8 +166,8 @@ static void pwm_imx27_get_state(struct pwm_chip *chip,
else
val = imx->duty_cycle;
- tmp = NSEC_PER_SEC * (u64)(val);
- state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, pwm_clk);
+ tmp = NSEC_PER_SEC * (u64)(val) * prescaler;
+ state->duty_cycle = DIV_ROUND_UP_ULL(tmp, pwm_clk);
pwm_imx27_clk_disable_unprepare(imx);
}
@@ -220,22 +219,23 @@ static int pwm_imx27_apply(struct pwm_chip *chip, struct pwm_device *pwm,
struct pwm_imx27_chip *imx = to_pwm_imx27_chip(chip);
struct pwm_state cstate;
unsigned long long c;
+ unsigned long long clkrate;
int ret;
u32 cr;
pwm_get_state(pwm, &cstate);
- c = clk_get_rate(imx->clk_per);
- c *= state->period;
+ clkrate = clk_get_rate(imx->clk_per);
+ c = clkrate * state->period;
- do_div(c, 1000000000);
+ do_div(c, NSEC_PER_SEC);
period_cycles = c;
prescale = period_cycles / 0x10000 + 1;
period_cycles /= prescale;
- c = (unsigned long long)period_cycles * state->duty_cycle;
- do_div(c, state->period);
+ c = clkrate * state->duty_cycle;
+ do_div(c, NSEC_PER_SEC * prescale);
duty_cycles = c;
/*
--
2.25.1
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next prev parent reply other threads:[~2020-06-18 1:33 UTC|newest]
Thread overview: 74+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20200618010805.600873-1-sashal@kernel.org>
2020-06-18 1:01 ` [PATCH AUTOSEL 5.7 003/388] clk: sunxi: Fix incorrect usage of round_down() Sasha Levin
2020-06-18 1:01 ` [PATCH AUTOSEL 5.7 007/388] ASoC: SOF: imx8: Fix randbuild error Sasha Levin
2020-06-18 1:01 ` [PATCH AUTOSEL 5.7 017/388] ARM: integrator: Add some Kconfig selections Sasha Levin
2020-06-18 1:01 ` [PATCH AUTOSEL 5.7 018/388] ARM: dts: stm32: Add missing ethernet PHY reset on AV96 Sasha Levin
2020-06-18 1:01 ` [PATCH AUTOSEL 5.7 021/388] arm64: dts: meson-gxbb-kii-pro: fix board compatible Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 024/388] arm64: dts: meson: fixup SCP sram nodes Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 031/388] PCI: brcmstb: Fix window register offset from 4 to 8 Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 039/388] clk: samsung: Mark top ISP and CAM clocks on Exynos542x as critical Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 042/388] usb: roles: Switch on role-switch uevent reporting Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 043/388] serial: 8250: Fix max baud limit in generic 8250 port Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 048/388] arm64: dts: armada-3720-turris-mox: forbid SDR104 on SDIO for FCC purposes Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 049/388] arm64: dts: armada-3720-turris-mox: fix SFP binding Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 050/388] arm64: dts: juno: Fix GIC child nodes Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 056/388] arm64: dts: fvp: " Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 057/388] PCI: aardvark: Don't blindly enable ASPM L0s and don't write to read-only register Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 059/388] arm64: dts: fvp/juno: Fix node address fields Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 062/388] coresight: tmc: Fix TMC mode read in tmc_read_prepare_etb() Sasha Levin
2020-06-18 1:02 ` [PATCH AUTOSEL 5.7 075/388] clk: zynqmp: fix memory leak in zynqmp_register_clocks Sasha Levin
2020-06-18 1:03 ` [PATCH AUTOSEL 5.7 089/388] clk: sprd: fix compile-testing Sasha Levin
2020-06-18 1:03 ` [PATCH AUTOSEL 5.7 094/388] ASoC: meson: fix memory leak of links if allocation of ldata fails Sasha Levin
2020-06-18 1:03 ` [PATCH AUTOSEL 5.7 103/388] ASoC: meson: add missing free_irq() in error path Sasha Levin
2020-06-18 1:03 ` [PATCH AUTOSEL 5.7 108/388] media: s5p-mfc: Properly handle dma_parms for the allocated devices Sasha Levin
2020-06-18 1:03 ` [PATCH AUTOSEL 5.7 114/388] ARM: dts: bcm283x: Use firmware PM driver for V3D Sasha Levin
2020-06-18 1:03 ` [PATCH AUTOSEL 5.7 115/388] arm64: dts: realtek: rtd129x: Fix GIC CPU masks for RTD1293 Sasha Levin
2020-06-18 1:03 ` [PATCH AUTOSEL 5.7 118/388] staging: mt7621-pci: fix PCIe interrupt mapping Sasha Levin
2020-06-18 1:03 ` [PATCH AUTOSEL 5.7 119/388] arm64: dts: mt8173: fix unit name warnings Sasha Levin
2020-06-18 1:03 ` [PATCH AUTOSEL 5.7 122/388] ARM: dts: sun8i-h2-plus-bananapi-m2-zero: Fix led polarity Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 151/388] clk: meson: meson8b: Fix the first parent of vid_pll_in_sel Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 152/388] clk: meson: meson8b: Fix the polarity of the RESET_N lines Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 153/388] clk: meson: meson8b: Fix the vclk_div{1, 2, 4, 6, 12}_en gate bits Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 158/388] arm64: dts: meson-g12b-ugoos-am6: fix board compatible Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 159/388] arm64: dts: meson: fix leds subnodes name Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 161/388] clk: meson: meson8b: Don't rely on u-boot to init all GP_PLL registers Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 164/388] ARM: dts: aspeed: ast2600: Set arch timer always-on Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 165/388] ARM: dts: aspeed: Change KCS nodes to v2 binding Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 168/388] usb: dwc3: meson-g12a: check return of dwc3_meson_g12a_usb_init Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 182/388] PCI: brcmstb: Assert fundamental reset on initialization Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 184/388] remoteproc/mediatek: fix invalid use of sizeof in scp_ipi_init() Sasha Levin
2020-06-18 1:04 ` [PATCH AUTOSEL 5.7 196/388] pinctrl: rockchip: fix memleak in rockchip_dt_node_to_map Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 214/388] arm64: dts: marvell: armada-37xx: Set pcie_reset_pin to gpio function Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 221/388] PCI: aardvark: Train link immediately after enabling training Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 222/388] PCI: aardvark: Improve link training Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 223/388] PCI: aardvark: Issue PERST via GPIO Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 227/388] iommu/arm-smmu-v3: Don't reserve implementation defined register space Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 229/388] usb/ohci-platform: Fix a warning when hibernating Sasha Levin
2020-06-18 9:56 ` Qais Yousef
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 235/388] coresight: Fix support for sparsely populated ports Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 236/388] coresight: etm4x: Fix use-after-free of per-cpu etm drvdata Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 238/388] clk: samsung: exynos5433: Add IGNORE_UNUSED flag to sclk_i2s1 Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 239/388] ARM: dts: meson: Switch existing boards with RGMII PHY to "rgmii-id" Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 244/388] firmware: imx: scu: Fix possible memory leak in imx_scu_probe() Sasha Levin
2020-06-18 1:05 ` [PATCH AUTOSEL 5.7 259/388] PCI: amlogic: meson: Don't use FAST_LINK_MODE to set up link Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 266/388] usb: gadget: lpc32xx_udc: don't dereference ep pointer before null check Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 269/388] pinctrl: Fix return value about devm_platform_ioremap_resource() Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 273/388] mfd: stmfx: Reset chip on resume as supply was disabled Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 274/388] mfd: stmfx: Fix stmfx_irq_init error path Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 275/388] mfd: stmfx: Disable IRQ in suspend to avoid spurious interrupt Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 282/388] clk: bcm2835: Fix return type of bcm2835_register_gate Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 284/388] clk: zynqmp: Fix divider2 calculation Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 292/388] misc: xilinx-sdfec: improve get_user_pages_fast() error handling Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 300/388] ARM: davinci: fix build failure without I2C Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 305/388] usb: dwc3: meson-g12a: fix error path when fetching the reset line fails Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 310/388] mailbox: imx: Fix return in imx_mu_scu_xlate() Sasha Levin
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 311/388] mailbox: zynqmp-ipi: Fix NULL vs IS_ERR() check in zynqmp_ipi_mbox_probe() Sasha Levin
2020-06-18 1:06 ` Sasha Levin [this message]
2020-06-18 1:06 ` [PATCH AUTOSEL 5.7 321/388] scsi: ufs: Don't update urgent bkops level when toggling auto bkops Sasha Levin
2020-06-18 1:07 ` [PATCH AUTOSEL 5.7 323/388] pinctrl: imxl: Fix an error handling path in 'imx1_pinctrl_core_probe()' Sasha Levin
2020-06-18 1:07 ` [PATCH AUTOSEL 5.7 324/388] pinctrl: sirf: add missing put_device() call in sirfsoc_gpio_probe() Sasha Levin
2020-06-18 1:07 ` [PATCH AUTOSEL 5.7 325/388] pinctrl: freescale: imx: Fix an error handling path in 'imx_pinctrl_probe()' Sasha Levin
2020-06-18 1:07 ` [PATCH AUTOSEL 5.7 326/388] pinctrl: freescale: imx: Use 'devm_of_iomap()' to avoid a resource leak in case of error " Sasha Levin
2020-06-18 1:07 ` [PATCH AUTOSEL 5.7 356/388] mailbox: imx: Add context save/restore for suspend/resume Sasha Levin
2020-06-18 1:07 ` [PATCH AUTOSEL 5.7 357/388] arm64: ftrace: Change CONFIG_FTRACE_WITH_REGS to CONFIG_DYNAMIC_FTRACE_WITH_REGS Sasha Levin
2020-06-18 1:07 ` [PATCH AUTOSEL 5.7 370/388] drm/sun4i: hdmi ddc clk: Fix size of m divider Sasha Levin
2020-06-18 1:07 ` [PATCH AUTOSEL 5.7 372/388] scsi: acornscsi: Fix an error handling path in acornscsi_probe() Sasha Levin
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