From patchwork Thu Feb 8 23:24:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Fabrizio Castro X-Patchwork-Id: 13550760 X-Patchwork-Delegate: geert@linux-m68k.org Received: from relmlie6.idc.renesas.com (relmlor2.renesas.com [210.160.252.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id F358255C0A; Thu, 8 Feb 2024 23:24:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=210.160.252.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707434700; cv=none; b=dYP5pR0JX5j/1iqwegatuj2phsY7fENfX9jh9m6327Rrp/Rs+VrzuJ6Q0uV80K1g0ai6nzI+FsivTcf4Kgh2Qmca9Jn2ViKmwQAq7gPBU6Nb7x+sizvr+B44fpjI8IAZyCpWGRWj+10r+v1IrAZL8aqzL6HTYOJoxo2fFsAvKn0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707434700; c=relaxed/simple; bh=WBaTzJzhM55xdVCvz86FKgtFn3EQiv0Ts6ceDlSKVNg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=TK6D/3Fl3DFQwHrrsLNqFA0kJ0gVnLFD0QxoShkTy3wS1Cc6mLOWn3yV0+3dIiumS62kNV5vvIXE6nfxV6CKYAHcoAAAtoDtz0gGgwVR4Sfy5P6FtsDdDRF6iJcoXdRjItMtmT7yyiUVBVt7RwLgQkYmZjEiV69bEyLQMg0Cbts= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=renesas.com; spf=pass smtp.mailfrom=renesas.com; arc=none smtp.client-ip=210.160.252.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=renesas.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=renesas.com X-IronPort-AV: E=Sophos;i="6.05,255,1701097200"; d="scan'208";a="197291931" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie6.idc.renesas.com with ESMTP; 09 Feb 2024 08:24:57 +0900 Received: from mulinux.home (unknown [10.226.92.227]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id CD10A4009BDC; Fri, 9 Feb 2024 08:24:54 +0900 (JST) From: Fabrizio Castro To: =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , Philipp Zabel , Geert Uytterhoeven Cc: Biju Das , Magnus Damm , linux-kernel@vger.kernel.org, linux-pwm@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Fabrizio Castro Subject: [PATCH v6 2/4] pwm: Add support for RZ/V2M PWM driver Date: Thu, 8 Feb 2024 23:24:09 +0000 Message-Id: <20240208232411.316936-3-fabrizio.castro.jz@renesas.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240208232411.316936-1-fabrizio.castro.jz@renesas.com> References: <20240208232411.316936-1-fabrizio.castro.jz@renesas.com> Precedence: bulk X-Mailing-List: linux-renesas-soc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Biju Das The RZ/V2{M, MA} PWM Timer supports the following functions: * The PWM has 24-bit counters which operate at PWM_CLK (48 MHz). * The frequency division ratio for internal counter operation is selectable as PWM_CLK divided by 1, 16, 256, or 2048. * The period as well as the duty cycle is adjustable. * The low-level and high-level order of the PWM signals can be inverted. * The duty cycle of the PWM signal is selectable in the range from 0 to 100%. * The minimum resolution is 20.83 ns. * Three interrupt sources: Rising and falling edges of the PWM signal and clearing of the counter * Counter operation and the bus interface are asynchronous and both can operate independently of the magnitude relationship of the respective clock periods. Signed-off-by: Biju Das Signed-off-by: Fabrizio Castro --- v5->v6: * Added Fab's Signed-off-by. * Updated copyright year to 2024. * Added include of limits.h. * Added variable max_period to rzv2m_pwm_chip. * Simplified the calculations by calculating max_period during probe, based on the numerical limits of the formula and the u64 data type. * Added rzv2m_pwm_mul_u64_u64_div_u64_roundup. * Added rzv2m_pwm_prescale_to_shift to fix the calculation of the frequency divider. * Improved the calculations and the variable names of rzv2m_pwm_get_state. * Improved the calculations of rzv2m_pwm_config. * Removed .owner from rzv2m_pwm_ops. * Improved rzv2m_pwm_pm_runtime_resume and renamed its err variable to ret. * Removed of_match_ptr. * Added Fab as module author. v4->v5: * Sorted KConfig file * Sorted Make file * Updated copyright header 2022->2023. * Updated limitation section. * Replaced the variable chip->rzv2m_pwm in rzv2m_pwm_wait_delay() * Replaced polarity logic as per HW manual dutycycle = Ton/Ton+Toff, so eventhough native polarity is inverted from period point of view it is correct. * Added logic for supporting 0% , 100% and remaining duty cycle. * On config() replaced * pm_runtime_resume_and_get()->pm_runtime_get_sync() * Counter is stopped while updating period/polarity to avoid glitches. * Added error check for clk_prepare_enable() * Introduced is_ch_enabled variable to cache channel enable status. * clk_get_rate is called after enabling the clock and * clk_rate_exclusive_get() * Added comment for delay * Replaced 1000000000UL->NSEC_PER_SEC. * Improved error handling in probe(). v3->v4: * Documented the hardware properties in "Limitations" section * Dropped the macros F2CYCLE_NSEC, U24_MASK and U24_MAX. * Added RZV2M_PWMCYC_PERIOD macro for U24_MAX * Dropped rzv2m_pwm_freq_div variable and started using 1 << (4 * i) for calculating divider as it is power of 16. * Reordered the functions to have rzv2m_pwm_config() directly before rzv2m_pwm_apply(). * Improved the logic for calculating period and duty cycle in config() * Merged multiple RZV2M_PWMCTR register writes to a single write in * config() * replaced pwm_is_enabled()->pwm->state.enabled * Avoided assigning bit value as enum pwm_polarity instead used enum * constant. * Fixed various issues in probe error path. * Updated the logic for PWM cycle setting register * A 100% duty cycle is only possible with PWMLOW > PWMCYC. So restricting PWMCYC values < 0xffffff * The native polarity of the hardware is inverted (i.e. it starts with the low part). So switched the inversion bit handling. v2->v3: * Added return code for rzv2m_pwm_get_state() * Added comment in rzv2m_pwm_reset_assert_pm_disable() v1->v2: * Replaced devm_reset_control_get_optional_shared->devm_reset_control_get_shared drivers/pwm/Kconfig | 11 + drivers/pwm/Makefile | 1 + drivers/pwm/pwm-rzv2m.c | 469 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 481 insertions(+) create mode 100644 drivers/pwm/pwm-rzv2m.c diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 4b956d661755..55d46e6183a2 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -524,6 +524,17 @@ config PWM_RZ_MTU3 To compile this driver as a module, choose M here: the module will be called pwm-rz-mtu3. +config PWM_RZV2M + tristate "Renesas RZ/V2M PWM support" + depends on ARCH_R9A09G011 || COMPILE_TEST + depends on HAS_IOMEM + help + This driver exposes the PWM controller found in Renesas + RZ/V2M like chips through the PWM API. + + To compile this driver as a module, choose M here: the module + will be called pwm-rzv2m. + config PWM_SAMSUNG tristate "Samsung PWM support" depends on PLAT_SAMSUNG || ARCH_S5PV210 || ARCH_EXYNOS || COMPILE_TEST diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index c5ec9e168ee7..cf5a4a1c3b1a 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -48,6 +48,7 @@ obj-$(CONFIG_PWM_RCAR) += pwm-rcar.o obj-$(CONFIG_PWM_RENESAS_TPU) += pwm-renesas-tpu.o obj-$(CONFIG_PWM_ROCKCHIP) += pwm-rockchip.o obj-$(CONFIG_PWM_RZ_MTU3) += pwm-rz-mtu3.o +obj-$(CONFIG_PWM_RZV2M) += pwm-rzv2m.o obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o obj-$(CONFIG_PWM_SIFIVE) += pwm-sifive.o obj-$(CONFIG_PWM_SL28CPLD) += pwm-sl28cpld.o diff --git a/drivers/pwm/pwm-rzv2m.c b/drivers/pwm/pwm-rzv2m.c new file mode 100644 index 000000000000..7aa07576a3c8 --- /dev/null +++ b/drivers/pwm/pwm-rzv2m.c @@ -0,0 +1,469 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Renesas RZ/V2M PWM Timer (PWM) driver + * + * Copyright (C) 2024 Renesas Electronics Corporation + * + * Hardware manual for this IP can be found here + * https://www.renesas.com/in/en/document/mah/rzv2m-users-manual-hardware?language=en + * + * Limitations: + * - Changes to the duty cycle configuration get effective only after the next + * period end. + * - The duty cycle can be changed only by modifying the PWMLOW register + *   value and changing the pulse width at low level. The duty cycle becomes + *   0% for the low width when the value of the PWMLOW register is 0x0h + *   and 100% for the low width when the value of the PWMLOW > PWMCYC. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define RZV2M_PWMCTR 0x0 +#define RZV2M_PWMCYC 0x4 +#define RZV2M_PWMLOW 0x8 +#define RZV2M_PWMCNT 0xc + +#define RZV2M_PWMCTR_PWMPS GENMASK(17, 16) +#define RZV2M_PWMCTR_PWMHL BIT(3) +#define RZV2M_PWMCTR_PWMTM BIT(2) +#define RZV2M_PWMCTR_PWME BIT(1) + +#define RZV2M_PWMCYC_PERIOD GENMASK(23, 0) +#define RZV2M_PWMLOW_PERIOD GENMASK(23, 0) + +struct rzv2m_pwm_chip { + u64 max_period; + struct pwm_chip chip; + void __iomem *mmio; + struct reset_control *rstc; + struct clk *apb_clk; + struct clk *pwm_clk; + unsigned long rate; + unsigned long delay; + unsigned long pwm_cyc; + enum pwm_polarity polarity; + bool is_ch_enabled; +}; + +static inline u64 rzv2m_pwm_mul_u64_u64_div_u64_roundup(u64 a, u64 b, u64 c) +{ + u64 ab = a * b; + + return ab / c + (ab % c ? 1 : 0); +} + +static inline struct rzv2m_pwm_chip *to_rzv2m_pwm_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct rzv2m_pwm_chip, chip); +} + +static void rzv2m_pwm_wait_delay(struct rzv2m_pwm_chip *rzv2m_pwm) +{ + /* delay timer when change the setting register */ + ndelay(rzv2m_pwm->delay); +} + +static void rzv2m_pwm_write(struct rzv2m_pwm_chip *rzv2m_pwm, u32 reg, u32 data) +{ + writel(data, rzv2m_pwm->mmio + reg); +} + +static u32 rzv2m_pwm_read(struct rzv2m_pwm_chip *rzv2m_pwm, u32 reg) +{ + return readl(rzv2m_pwm->mmio + reg); +} + +static void rzv2m_pwm_modify(struct rzv2m_pwm_chip *rzv2m_pwm, u32 reg, u32 clr, + u32 set) +{ + rzv2m_pwm_write(rzv2m_pwm, reg, + (rzv2m_pwm_read(rzv2m_pwm, reg) & ~clr) | set); +} + +static u8 rzv2m_pwm_calculate_prescale(struct rzv2m_pwm_chip *rzv2m_pwm, + u64 period_cycles) +{ + u32 prescaled_period_cycles; + u8 prescale; + + prescaled_period_cycles = period_cycles >> 24; + if (prescaled_period_cycles >= 256) + prescale = 3; + else + prescale = (fls(prescaled_period_cycles) + 3) / 4; + + return prescale; +} + +static inline int rzv2m_pwm_prescale_to_shift(u8 prescale) +{ + return prescale == 3 ? 11 : prescale * 4; +} + +static int rzv2m_pwm_enable(struct rzv2m_pwm_chip *rzv2m_pwm) +{ + int rc; + + rc = pm_runtime_resume_and_get(rzv2m_pwm->chip.dev); + if (rc) + return rc; + + rzv2m_pwm_modify(rzv2m_pwm, RZV2M_PWMCTR, RZV2M_PWMCTR_PWME, + RZV2M_PWMCTR_PWME); + rzv2m_pwm_wait_delay(rzv2m_pwm); + rzv2m_pwm->is_ch_enabled = true; + + return 0; +} + +static void rzv2m_pwm_disable(struct rzv2m_pwm_chip *rzv2m_pwm) +{ + rzv2m_pwm_modify(rzv2m_pwm, RZV2M_PWMCTR, RZV2M_PWMCTR_PWME, 0); + rzv2m_pwm_wait_delay(rzv2m_pwm); + pm_runtime_put_sync(rzv2m_pwm->chip.dev); + rzv2m_pwm->is_ch_enabled = false; +} + +static int rzv2m_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct rzv2m_pwm_chip *rzv2m_pwm = to_rzv2m_pwm_chip(chip); + u16 frequency_divisor; + u32 ctr, cyc, low; + u8 prescale; + + pm_runtime_get_sync(chip->dev); + ctr = rzv2m_pwm_read(rzv2m_pwm, RZV2M_PWMCTR); + state->enabled = FIELD_GET(RZV2M_PWMCTR_PWME, ctr); + state->polarity = FIELD_GET(RZV2M_PWMCTR_PWMHL, ctr) ? + PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL; + prescale = FIELD_GET(RZV2M_PWMCTR_PWMPS, ctr); + frequency_divisor = 1 << rzv2m_pwm_prescale_to_shift(prescale); + + cyc = rzv2m_pwm_read(rzv2m_pwm, RZV2M_PWMCYC); + state->period = rzv2m_pwm_mul_u64_u64_div_u64_roundup(cyc + 1, + NSEC_PER_SEC * frequency_divisor, + rzv2m_pwm->rate); + + low = rzv2m_pwm_read(rzv2m_pwm, RZV2M_PWMLOW); + state->duty_cycle = rzv2m_pwm_mul_u64_u64_div_u64_roundup(cyc + 1 - low, + NSEC_PER_SEC * frequency_divisor, + rzv2m_pwm->rate); + + return pm_runtime_put(chip->dev); +} + +static int rzv2m_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct rzv2m_pwm_chip *rzv2m_pwm = to_rzv2m_pwm_chip(chip); + u64 period = state->period, duty_cycle = state->duty_cycle; + u16 frequency_divisor; + u64 pwm_cyc, pwm_low; + u8 prescale; + u32 pwm_ctr; + + /* + * Clamp period and duty cycle to their maximum values for our current + * configuration rather than letting our calculations overflow. + */ + if (period > rzv2m_pwm->max_period) { + period = rzv2m_pwm->max_period; + if (duty_cycle > rzv2m_pwm->max_period) + duty_cycle = period; + } + + /* + * Formula for calculating PWM Cycle Setting Register: + * PWM cycle = (PWM period(ns) / (PWM_CLK period(ns) × Div ratio)) - 1 + */ + pwm_cyc = (period * rzv2m_pwm->rate) / NSEC_PER_SEC; + pwm_cyc = pwm_cyc ? pwm_cyc : 1; + + prescale = rzv2m_pwm_calculate_prescale(rzv2m_pwm, pwm_cyc - 1); + frequency_divisor = 1 << rzv2m_pwm_prescale_to_shift(prescale); + if (frequency_divisor > 1) { + pwm_cyc = (period * rzv2m_pwm->rate) / + (NSEC_PER_SEC * frequency_divisor); + pwm_cyc = pwm_cyc ? pwm_cyc : 1; + } + + if (pwm_cyc && !FIELD_FIT(RZV2M_PWMCYC_PERIOD, pwm_cyc - 1)) + pwm_cyc = RZV2M_PWMCYC_PERIOD + 1; + + /* + * Formula for calculating PWMLOW register: + * PWMLOW register = PWM cycle * Low pulse width ratio (%) + */ + pwm_low = (duty_cycle * rzv2m_pwm->rate) / + (NSEC_PER_SEC * frequency_divisor); + + pwm_low = pwm_cyc - pwm_low; + if (!FIELD_FIT(RZV2M_PWMLOW_PERIOD, pwm_low)) + pwm_low = RZV2M_PWMLOW_PERIOD; + + pwm_cyc--; + + /* + * If the PWM channel is disabled, make sure to turn on the clock + * before writing the register. + */ + if (!pwm->state.enabled) + pm_runtime_get_sync(rzv2m_pwm->chip.dev); + + /* + * To change the setting value of the PWM cycle setting register + * (PWMm_PWMCYC) or polarity, set the PWME bit of the PWM control + * register (PWMm_PWMCTR) to 0b and stop the counter operation. + */ + if (rzv2m_pwm->polarity != state->polarity || rzv2m_pwm->pwm_cyc != pwm_cyc) { + rzv2m_pwm_modify(rzv2m_pwm, RZV2M_PWMCTR, RZV2M_PWMCTR_PWME, 0); + rzv2m_pwm_wait_delay(rzv2m_pwm); + } + + rzv2m_pwm_write(rzv2m_pwm, RZV2M_PWMCYC, pwm_cyc); + rzv2m_pwm_write(rzv2m_pwm, RZV2M_PWMLOW, pwm_low); + + pwm_ctr = FIELD_PREP(RZV2M_PWMCTR_PWMPS, prescale); + if (state->polarity == PWM_POLARITY_INVERSED) + pwm_ctr |= RZV2M_PWMCTR_PWMHL; + + rzv2m_pwm_modify(rzv2m_pwm, RZV2M_PWMCTR, RZV2M_PWMCTR_PWMTM | + RZV2M_PWMCTR_PWMPS | RZV2M_PWMCTR_PWMHL, pwm_ctr); + + if (rzv2m_pwm->polarity != state->polarity || rzv2m_pwm->pwm_cyc != pwm_cyc) { + rzv2m_pwm->polarity = state->polarity; + rzv2m_pwm->pwm_cyc = pwm_cyc; + rzv2m_pwm_modify(rzv2m_pwm, RZV2M_PWMCTR, RZV2M_PWMCTR_PWME, + RZV2M_PWMCTR_PWME); + } + + rzv2m_pwm_wait_delay(rzv2m_pwm); + + /* If the PWM is not enabled, turn the clock off again to save power. */ + if (!pwm->state.enabled) + pm_runtime_put(rzv2m_pwm->chip.dev); + + return 0; +} + +static int rzv2m_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct rzv2m_pwm_chip *rzv2m_pwm = to_rzv2m_pwm_chip(chip); + bool enabled = pwm->state.enabled; + int ret; + + if (!state->enabled) { + if (enabled) + rzv2m_pwm_disable(rzv2m_pwm); + + return 0; + } + + ret = rzv2m_pwm_config(chip, pwm, state); + if (ret) + return ret; + + if (!enabled) + ret = rzv2m_pwm_enable(rzv2m_pwm); + + return ret; +} + +static const struct pwm_ops rzv2m_pwm_ops = { + .get_state = rzv2m_pwm_get_state, + .apply = rzv2m_pwm_apply, +}; + +static int rzv2m_pwm_pm_runtime_suspend(struct device *dev) +{ + struct rzv2m_pwm_chip *rzv2m_pwm = dev_get_drvdata(dev); + + clk_disable_unprepare(rzv2m_pwm->pwm_clk); + clk_disable_unprepare(rzv2m_pwm->apb_clk); + + return 0; +} + +static int rzv2m_pwm_pm_runtime_resume(struct device *dev) +{ + struct rzv2m_pwm_chip *rzv2m_pwm = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(rzv2m_pwm->apb_clk); + if (ret) + return ret; + + ret = clk_prepare_enable(rzv2m_pwm->pwm_clk); + if (ret) + clk_disable_unprepare(rzv2m_pwm->apb_clk); + + return ret; +} + +static DEFINE_RUNTIME_DEV_PM_OPS(rzv2m_pwm_pm_ops, + rzv2m_pwm_pm_runtime_suspend, + rzv2m_pwm_pm_runtime_resume, NULL); + +static void rzv2m_pwm_reset_assert_pm_disable(void *data) +{ + struct rzv2m_pwm_chip *rzv2m_pwm = data; + + /* + * The below check is for making balanced PM usage count in probe/remove + * eg: boot loader is turning on PWM and probe increments the PM usage + * count. Before apply, if there is unbind/remove callback we need to + * decrement the PM usage count. + */ + if (rzv2m_pwm->is_ch_enabled) + pm_runtime_put(rzv2m_pwm->chip.dev); + + clk_rate_exclusive_put(rzv2m_pwm->pwm_clk); + clk_rate_exclusive_put(rzv2m_pwm->apb_clk); + pm_runtime_disable(rzv2m_pwm->chip.dev); + pm_runtime_set_suspended(rzv2m_pwm->chip.dev); + reset_control_assert(rzv2m_pwm->rstc); +} + +static int rzv2m_pwm_probe(struct platform_device *pdev) +{ + struct rzv2m_pwm_chip *rzv2m_pwm; + unsigned long apb_clk_rate; + int ret; + + rzv2m_pwm = devm_kzalloc(&pdev->dev, sizeof(*rzv2m_pwm), GFP_KERNEL); + if (!rzv2m_pwm) + return -ENOMEM; + + rzv2m_pwm->mmio = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(rzv2m_pwm->mmio)) + return PTR_ERR(rzv2m_pwm->mmio); + + rzv2m_pwm->apb_clk = devm_clk_get(&pdev->dev, "apb"); + if (IS_ERR(rzv2m_pwm->apb_clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(rzv2m_pwm->apb_clk), + "cannot get apb clock\n"); + + rzv2m_pwm->pwm_clk = devm_clk_get(&pdev->dev, "pwm"); + if (IS_ERR(rzv2m_pwm->pwm_clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(rzv2m_pwm->pwm_clk), + "cannot get pwm clock\n"); + + rzv2m_pwm->rstc = devm_reset_control_get_shared(&pdev->dev, NULL); + if (IS_ERR(rzv2m_pwm->rstc)) + return dev_err_probe(&pdev->dev, PTR_ERR(rzv2m_pwm->rstc), + "get reset failed\n"); + + platform_set_drvdata(pdev, rzv2m_pwm); + ret = reset_control_deassert(rzv2m_pwm->rstc); + if (ret) { + return dev_err_probe(&pdev->dev, ret, + "cannot deassert reset control\n"); + } + + ret = clk_prepare_enable(rzv2m_pwm->apb_clk); + if (ret < 0) + goto err_reset; + + ret = clk_prepare_enable(rzv2m_pwm->pwm_clk); + if (ret < 0) + goto disable_apb_clk; + + clk_rate_exclusive_get(rzv2m_pwm->apb_clk); + clk_rate_exclusive_get(rzv2m_pwm->pwm_clk); + apb_clk_rate = clk_get_rate(rzv2m_pwm->apb_clk); + if (!apb_clk_rate) + goto err_rate_put; + + rzv2m_pwm->rate = clk_get_rate(rzv2m_pwm->pwm_clk); + if (!rzv2m_pwm->rate) + goto err_rate_put; + rzv2m_pwm->max_period = U64_MAX / rzv2m_pwm->rate; + + /* + * The registers other than the PWM interrupt register (PWMINT) are + * always synchronized with PWM_CLK at regular intervals. It takes some + * time (Min: 2 × PCLK + 4 × PWM_CLK to Max: 6 × PCLK + 9 × PWM_CLK) for + * the value set in the register to be reflected in the PWM circuit + * because there is a synchronizer between the register and the PWM + * circuit. + */ + rzv2m_pwm->delay = 6 * DIV_ROUND_UP(NSEC_PER_SEC, apb_clk_rate) + + 9 * DIV_ROUND_UP(NSEC_PER_SEC, rzv2m_pwm->rate); + + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + /* + * We need to keep the clock on, in case the bootloader has enabled the + * PWM and is running during probe(). + */ + if (!!(rzv2m_pwm_read(rzv2m_pwm, RZV2M_PWMCTR) & RZV2M_PWMCTR_PWME)) { + u32 val; + + pm_runtime_get_sync(&pdev->dev); + rzv2m_pwm->is_ch_enabled = true; + rzv2m_pwm->pwm_cyc = rzv2m_pwm_read(rzv2m_pwm, RZV2M_PWMCYC); + val = rzv2m_pwm_read(rzv2m_pwm, RZV2M_PWMCTR); + rzv2m_pwm->polarity = FIELD_GET(RZV2M_PWMCTR_PWMHL, val) ? + PWM_POLARITY_NORMAL : PWM_POLARITY_INVERSED; + } + + rzv2m_pwm->chip.dev = &pdev->dev; + ret = devm_add_action_or_reset(&pdev->dev, + rzv2m_pwm_reset_assert_pm_disable, + rzv2m_pwm); + if (ret) + return ret; + + rzv2m_pwm->chip.ops = &rzv2m_pwm_ops; + rzv2m_pwm->chip.npwm = 1; + ret = devm_pwmchip_add(&pdev->dev, &rzv2m_pwm->chip); + if (ret) + return dev_err_probe(&pdev->dev, ret, "failed to add PWM chip\n"); + + pm_runtime_idle(&pdev->dev); + + return 0; + +err_rate_put: + clk_rate_exclusive_put(rzv2m_pwm->pwm_clk); + clk_rate_exclusive_put(rzv2m_pwm->apb_clk); + clk_disable_unprepare(rzv2m_pwm->pwm_clk); +disable_apb_clk: + clk_disable_unprepare(rzv2m_pwm->apb_clk); +err_reset: + reset_control_assert(rzv2m_pwm->rstc); + return ret; +} + +static const struct of_device_id rzv2m_pwm_of_table[] = { + { .compatible = "renesas,rzv2m-pwm", }, + { /* Sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rzv2m_pwm_of_table); + +static struct platform_driver rzv2m_pwm_driver = { + .driver = { + .name = "pwm-rzv2m", + .pm = pm_ptr(&rzv2m_pwm_pm_ops), + .of_match_table = rzv2m_pwm_of_table, + }, + .probe = rzv2m_pwm_probe, +}; +module_platform_driver(rzv2m_pwm_driver); + +MODULE_AUTHOR("Biju Das "); +MODULE_AUTHOR("Fabrizio Castro "); +MODULE_DESCRIPTION("Renesas RZ/V2M PWM Timer Driver"); +MODULE_LICENSE("GPL");