From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10E75C77B75 for ; Tue, 18 Apr 2023 10:22:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231290AbjDRKWQ (ORCPT ); Tue, 18 Apr 2023 06:22:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46816 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230032AbjDRKVs (ORCPT ); Tue, 18 Apr 2023 06:21:48 -0400 Received: from relmlie5.idc.renesas.com (relmlor1.renesas.com [210.160.252.171]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 5AB9B6E9E; Tue, 18 Apr 2023 03:20:43 -0700 (PDT) X-IronPort-AV: E=Sophos;i="5.99,206,1677510000"; d="scan'208";a="156394551" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie5.idc.renesas.com with ESMTP; 18 Apr 2023 19:20:42 +0900 Received: from localhost.localdomain (unknown [10.226.92.32]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id C849E400A653; Tue, 18 Apr 2023 19:20:39 +0900 (JST) From: Biju Das To: Thierry Reding Cc: Biju Das , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , linux-pwm@vger.kernel.org, Geert Uytterhoeven , Prabhakar Mahadev Lad , linux-renesas-soc@vger.kernel.org Subject: [PATCH v16] pwm: Add Renesas RZ/G2L MTU3a PWM driver Date: Tue, 18 Apr 2023 11:20:37 +0100 Message-Id: <20230418102037.346405-1-biju.das.jz@bp.renesas.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org The RZ/G2L Multi-Function Timer Pulse Unit 3 (a.k.a MTU3a) uses one counter and two match components to configure duty_cycle and period to generate PWM output waveform. Add basic support for RZ/G2L MTU3a PWM driver by creating separate PWM channels for each IOs. Signed-off-by: Biju Das --- This patch series depend upon linux-next [1] [1] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?h=next-20230417&id=bbd4013b44e6c21b997c1fa18ee635a9f3b1c4cc v15->v16: * Fixed extra space around hwpwm check on rz_mtu3_get_channel(). * Dropped redundant is_channel_en check on rz_mtu3_pwm_is_ch_enabled(). * Replaced channel->base_pwm_number in struct rz_mtu3_channel_io_map. * Added comment for channel_map. * Dropped setting normal mode in rz_mtu3_pwm_disable(). * Replaced ddata->parent_ddata in probe() * Added support for modifying prescalar, if other PWM is off or handle it, if current prescale value is less than the one we want to set. * Added below helper functions rz_mtu3_pwm_calculate_pv_or_dc() and rz_mtu3_pwm_{read,write}_tgr_registers to simplify the code. v14->v15: * Updated copyright header and Limitations section * Moved register definitions to * Introduced new mapping table struct rz_mtu3_channel_io_map to hold the index of the lowest PWM and the number of PWMs handled by the HW channel. * Introduced struct rz_mtu3_pwm_channel to hold mtu3 channel data and mapping table. * Replaced rz_mtu3_get_hw_channel->rz_mtu3_get_channel and channel->hwpwm. The rz_mtu3_get_channel() returns struct rz_mtu3_pwm_channel* * Dropped rz_mtu3_pwm_is_second_channel() as same can be obtained directly with new mapping (ie, priv->map->channel == pwm->hwpwm) * Replaced ch_index->ch throughout and used "priv - rz_mtu3_pwm->channel_data" to find ch and dropped rz_mtu3_get_hw_channel_index(). * Optimized rz_mtu3_pwm_is_ch_enabled() by exit early, if is_channel_en is false. * Updated rz_mtu3_pwm_request() and added comments. * Introduced a bug in the driver by introducing enable_count, which increment/ decrement during enable()/disable(). * Reduced variable scope in rz_mtu3_pwm_get_state() by moving most of variables inside the if statement. * Updated probe() to assign the struct rz_mtu3_pwm_channel values. v13->v14: * Updated commit description * Updated Limitations section. * Replaced the macros RZ_MTU*->RZ_MTU3_CHAN_* in probe() * Fixed a kernel crash in error path by moving rz_mtu3_pwm->chip.dev before devm_add_action_or_reset() * Added pm_runtime_idle() and simplified error paths for devm_add_action_or_reset() and devm_pwmchip_add(). v12->v13: * Updated commit description * Moved RZ_MTU3_TMDR1_MD_* macros to rz_mtu3.h * Updated Limitations section. * Removed PWM mode1 references from the driver. * Dropped prescale and duty_cycle from struct rz_mtu3_pwm_chip. * Replaced rz_mtu3_pwm_mode1_num_ios->rz_mtu3_hw_channel_ios. * Avoided race condition in rz_mtu3_pwm_request()/rz_mtu3_pwm_free(). * Updated get_state() by adding dc > pv check and added a comment about overflow condition. * Moved overflow condition check from config->probe() * Replaced pm_runtime_resume_and_get with unconditional pm_runtime_get_sync() in config() * Added error check for clk_prepare_enable() in probe() and propagating error to the caller for pm_runtime_resume() * clk_get_rate() is called after enabling the clock and clk_rate_exclusive_put() v11->v12: * Updated header file to as core driver is in MFD. * Reordered get_state() v10->v11: * No change. v9->v10: * No change. v8->v9: * Added prescale/duty_cycle variables to struct rz_mtu3_pwm_chip and cached this values in rz_mtu3_pwm_config and used this cached values in get_state(), if PWM is disabled. * Added return code for get_state() v7->v8: * Simplified rz_mtu3_pwm_request by calling rz_mtu3_request_channel() * Simplified rz_mtu3_pwm_free by calling rz_mtu3_release_channel() v6->v7: * Added channel specific mutex lock to avoid race between counter device and rz_mtu3_pwm_{request,free} * Added pm_runtime_resume_and_get in rz_mtu3_pwm_enable() * Added pm_runtime_put_sync in rz_mtu3_pwm_disable() * Updated rz_mtu3_pwm_config() * Updated rz_mtu3_pwm_apply() v5->v6: * Updated commit and Kconfig description * Sorted the header * Replaced dev_get_drvdata from rz_mtu3_pwm_pm_disable() * Replaced SET_RUNTIME_PM_OPS->DEFINE_RUNTIME_DEV_PM_OPS and removed __maybe_unused from suspend/resume() v4->v5: * pwm device is instantiated by mtu3a core driver. v3->v4: * There is no resource associated with "rz-mtu3-pwm" compatible and moved the code to mfd subsystem as it binds against "rz-mtu". * Removed struct platform_driver rz_mtu3_pwm_driver. v2->v3: * No change. v1->v2: * Modelled as a single PWM device handling multiple channles. * Used PM framework to manage the clocks. --- drivers/pwm/Kconfig | 11 + drivers/pwm/Makefile | 1 + drivers/pwm/pwm-rz-mtu3.c | 539 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 551 insertions(+) create mode 100644 drivers/pwm/pwm-rz-mtu3.c diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 8df861b1f4a3..ac0517b51540 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -493,6 +493,17 @@ config PWM_ROCKCHIP Generic PWM framework driver for the PWM controller found on Rockchip SoCs. +config PWM_RZ_MTU3 + tristate "Renesas RZ/G2L MTU3a PWM Timer support" + depends on RZ_MTU3 || COMPILE_TEST + depends on HAS_IOMEM + help + This driver exposes the MTU3a PWM Timer controller found in Renesas + RZ/G2L like chips through the PWM API. + + To compile this driver as a module, choose M here: the module + will be called pwm-rz-mtu3. + 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 19899b912e00..68b7a15c2ca5 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -45,6 +45,7 @@ obj-$(CONFIG_PWM_RASPBERRYPI_POE) += pwm-raspberrypi-poe.o obj-$(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_SAMSUNG) += pwm-samsung.o obj-$(CONFIG_PWM_SIFIVE) += pwm-sifive.o obj-$(CONFIG_PWM_SL28CPLD) += pwm-sl28cpld.o diff --git a/drivers/pwm/pwm-rz-mtu3.c b/drivers/pwm/pwm-rz-mtu3.c new file mode 100644 index 000000000000..4e63c20e3198 --- /dev/null +++ b/drivers/pwm/pwm-rz-mtu3.c @@ -0,0 +1,539 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Renesas RZ/G2L MTU3a PWM Timer driver + * + * Copyright (C) 2023 Renesas Electronics Corporation + * + * Hardware manual for this IP can be found here + * https://www.renesas.com/eu/en/document/mah/rzg2l-group-rzg2lc-group-users-manual-hardware-0?language=en + * + * Limitations: + * - When PWM is disabled, the output is driven to Hi-Z. + * - While the hardware supports both polarities, the driver (for now) + * only handles normal polarity. + * - HW uses one counter and two match components to configure duty_cycle + * and period. + * - Multi-Function Timer Pulse Unit (a.k.a MTU) has 7 HW channels for PWM + * operations. (The channels are MTU{0..4, 6, 7}.) + * - MTU{1, 2} channels have a single IO, whereas all other HW channels have + * 2 IOs. + * - Each IO is modelled as an independent PWM channel. + * - rz_mtu3_channel_io_map table is used to map the PWM channel to the + * corresponding HW channel as there are difference in number of IOs + * between HW channels. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define RZ_MTU3_MAX_PWM_CHANNELS 12 +#define RZ_MTU3_MAX_HW_CHANNELS 7 + +/** + * struct rz_mtu3_channel_io_map - MTU3 pwm channel map + * + * @base_pwm_number: First PWM of a channel + * @num: number of IOs on the HW channel. + */ +struct rz_mtu3_channel_io_map { + u8 base_pwm_number; + u8 num_channel_ios; +}; + +/** + * struct rz_mtu3_pwm_channel - MTU3 pwm channel data + * + * @mtu: MTU3 channel data + * @map: MTU3 pwm channel map + */ +struct rz_mtu3_pwm_channel { + struct rz_mtu3_channel *mtu; + const struct rz_mtu3_channel_io_map *map; +}; + +/** + * struct rz_mtu3_pwm_chip - MTU3 pwm private data + * + * @chip: MTU3 pwm chip data + * @clk: MTU3 module clock + * @lock: Lock to prevent concurrent access for usage count + * @rate: MTU3 clock rate + * @user_count: MTU3 usage count + * @enable_count: MTU3 enable count + * @prescale: MTU3 prescale + * @channel_data: MTU3 pwm channel data + */ + +struct rz_mtu3_pwm_chip { + struct pwm_chip chip; + struct clk *clk; + struct mutex lock; + unsigned long rate; + u32 user_count[RZ_MTU3_MAX_HW_CHANNELS]; + u32 enable_count[RZ_MTU3_MAX_HW_CHANNELS]; + u8 prescale[RZ_MTU3_MAX_HW_CHANNELS]; + struct rz_mtu3_pwm_channel channel_data[RZ_MTU3_MAX_HW_CHANNELS]; +}; + +/* + * The MTU channels are {0..4, 6, 7} and the number of IO on MTU1 + * and MTU2 channel is 1 compared to 2 on others. + */ +static const struct rz_mtu3_channel_io_map channel_map[] = { + { 0, 2 }, { 2, 1 }, { 3, 1 }, { 4, 2 }, { 6, 2 }, { 8, 2 }, { 10, 2 } +}; + +static inline struct rz_mtu3_pwm_chip *to_rz_mtu3_pwm_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct rz_mtu3_pwm_chip, chip); +} + +static void rz_mtu3_pwm_read_tgr_registers(struct rz_mtu3_pwm_channel *priv, + u16 reg_pv_offset, u16 *pv_val, + u16 reg_dc_offset, u16 *dc_val) +{ + *pv_val = rz_mtu3_16bit_ch_read(priv->mtu, reg_pv_offset); + *dc_val = rz_mtu3_16bit_ch_read(priv->mtu, reg_dc_offset); +} + +static void rz_mtu3_pwm_write_tgr_registers(struct rz_mtu3_pwm_channel *priv, + u16 reg_pv_offset, u16 pv_val, + u16 reg_dc_offset, u16 dc_val) +{ + rz_mtu3_16bit_ch_write(priv->mtu, reg_pv_offset, pv_val); + rz_mtu3_16bit_ch_write(priv->mtu, reg_dc_offset, dc_val); +} + +static u8 rz_mtu3_pwm_calculate_prescale(struct rz_mtu3_pwm_chip *rz_mtu3, + u64 period_cycles) +{ + u32 prescaled_period_cycles; + u8 prescale; + + prescaled_period_cycles = period_cycles >> 16; + if (prescaled_period_cycles >= 16) + prescale = 3; + else + prescale = (fls(prescaled_period_cycles) + 1) / 2; + + return prescale; +} + +static struct rz_mtu3_pwm_channel * +rz_mtu3_get_channel(struct rz_mtu3_pwm_chip *rz_mtu3_pwm, u32 hwpwm) +{ + struct rz_mtu3_pwm_channel *priv = rz_mtu3_pwm->channel_data; + unsigned int ch; + + for (ch = 0; ch < RZ_MTU3_MAX_HW_CHANNELS; ch++, priv++) { + if (priv->map->base_pwm_number + priv->map->num_channel_ios > hwpwm) + break; + } + + return priv; +} + +static bool rz_mtu3_pwm_is_ch_enabled(struct rz_mtu3_pwm_chip *rz_mtu3_pwm, + u32 hwpwm) +{ + struct rz_mtu3_pwm_channel *priv; + bool is_channel_en; + u8 val; + + priv = rz_mtu3_get_channel(rz_mtu3_pwm, hwpwm); + is_channel_en = rz_mtu3_is_enabled(priv->mtu); + if (!is_channel_en) + return false; + + if (priv->map->base_pwm_number == hwpwm) + val = rz_mtu3_8bit_ch_read(priv->mtu, RZ_MTU3_TIORH); + else + val = rz_mtu3_8bit_ch_read(priv->mtu, RZ_MTU3_TIORL); + + return val & RZ_MTU3_TIOR_IOA; +} + +static int rz_mtu3_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip); + struct rz_mtu3_pwm_channel *priv; + bool is_mtu3_channel_available; + u32 ch; + + priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm); + ch = priv - rz_mtu3_pwm->channel_data; + + mutex_lock(&rz_mtu3_pwm->lock); + /* + * Each channel must be requested only once, so if the channel + * serves two PWMs and the other is already requested, skip over + * rz_mtu3_request_channel() + */ + if (!rz_mtu3_pwm->user_count[ch]) { + is_mtu3_channel_available = rz_mtu3_request_channel(priv->mtu); + if (!is_mtu3_channel_available) { + mutex_unlock(&rz_mtu3_pwm->lock); + return -EBUSY; + } + } + + rz_mtu3_pwm->user_count[ch]++; + mutex_unlock(&rz_mtu3_pwm->lock); + + return 0; +} + +static void rz_mtu3_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip); + struct rz_mtu3_pwm_channel *priv; + u32 ch; + + priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm); + ch = priv - rz_mtu3_pwm->channel_data; + + mutex_lock(&rz_mtu3_pwm->lock); + rz_mtu3_pwm->user_count[ch]--; + if (!rz_mtu3_pwm->user_count[ch]) + rz_mtu3_release_channel(priv->mtu); + + mutex_unlock(&rz_mtu3_pwm->lock); +} + +static int rz_mtu3_pwm_enable(struct rz_mtu3_pwm_chip *rz_mtu3_pwm, + struct pwm_device *pwm) +{ + struct rz_mtu3_pwm_channel *priv; + u32 ch; + u8 val; + int rc; + + rc = pm_runtime_resume_and_get(rz_mtu3_pwm->chip.dev); + if (rc) + return rc; + + priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm); + ch = priv - rz_mtu3_pwm->channel_data; + val = RZ_MTU3_TIOR_OC_IOB_TOGGLE | RZ_MTU3_TIOR_OC_IOA_H_COMP_MATCH; + + rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TMDR1, RZ_MTU3_TMDR1_MD_PWMMODE1); + if (priv->map->base_pwm_number == pwm->hwpwm) + rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TIORH, val); + else + rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TIORL, val); + + mutex_lock(&rz_mtu3_pwm->lock); + if (!rz_mtu3_pwm->enable_count[ch]) + rz_mtu3_enable(priv->mtu); + + rz_mtu3_pwm->enable_count[ch]++; + mutex_unlock(&rz_mtu3_pwm->lock); + + return 0; +} + +static void rz_mtu3_pwm_disable(struct rz_mtu3_pwm_chip *rz_mtu3_pwm, + struct pwm_device *pwm) +{ + struct rz_mtu3_pwm_channel *priv; + u32 ch; + + priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm); + ch = priv - rz_mtu3_pwm->channel_data; + + /* Disable output pins of MTU3 channel */ + if (priv->map->base_pwm_number == pwm->hwpwm) + rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TIORH, RZ_MTU3_TIOR_OC_RETAIN); + else + rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TIORL, RZ_MTU3_TIOR_OC_RETAIN); + + mutex_lock(&rz_mtu3_pwm->lock); + rz_mtu3_pwm->enable_count[ch]--; + if (!rz_mtu3_pwm->enable_count[ch]) + rz_mtu3_disable(priv->mtu); + + mutex_unlock(&rz_mtu3_pwm->lock); + + pm_runtime_put_sync(rz_mtu3_pwm->chip.dev); +} + +static int rz_mtu3_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip); + + pm_runtime_get_sync(chip->dev); + state->enabled = rz_mtu3_pwm_is_ch_enabled(rz_mtu3_pwm, pwm->hwpwm); + if (state->enabled) { + struct rz_mtu3_pwm_channel *priv; + u8 prescale, val; + u16 dc, pv; + u64 tmp; + + priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm); + if (priv->map->base_pwm_number == pwm->hwpwm) + rz_mtu3_pwm_read_tgr_registers(priv, RZ_MTU3_TGRA, &pv, + RZ_MTU3_TGRB, &dc); + else + rz_mtu3_pwm_read_tgr_registers(priv, RZ_MTU3_TGRC, &pv, + RZ_MTU3_TGRD, &dc); + + val = rz_mtu3_8bit_ch_read(priv->mtu, RZ_MTU3_TCR); + prescale = FIELD_GET(RZ_MTU3_TCR_TPCS, val); + + /* With prescale <= 7 and pv <= 0xffff this doesn't overflow. */ + tmp = NSEC_PER_SEC * (u64)pv << (2 * prescale); + state->period = DIV_ROUND_UP_ULL(tmp, rz_mtu3_pwm->rate); + tmp = NSEC_PER_SEC * (u64)dc << (2 * prescale); + state->duty_cycle = DIV_ROUND_UP_ULL(tmp, rz_mtu3_pwm->rate); + } + + if (state->duty_cycle > state->period) + state->duty_cycle = state->period; + + state->polarity = PWM_POLARITY_NORMAL; + pm_runtime_put(chip->dev); + + return 0; +} + +static u16 rz_mtu3_pwm_calculate_pv_or_dc(u64 period_or_duty_cycle, u8 prescale) +{ + return (period_or_duty_cycle >> (2 * prescale)) <= U16_MAX ? + period_or_duty_cycle >> (2 * prescale) : U16_MAX; +} + +static int rz_mtu3_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip); + struct rz_mtu3_pwm_channel *priv; + u64 period_cycles; + u64 duty_cycles; + u8 prescale; + u16 pv, dc; + u8 val; + u32 ch; + + priv = rz_mtu3_get_channel(rz_mtu3_pwm, pwm->hwpwm); + ch = priv - rz_mtu3_pwm->channel_data; + + period_cycles = mul_u64_u32_div(state->period, rz_mtu3_pwm->rate, + NSEC_PER_SEC); + prescale = rz_mtu3_pwm_calculate_prescale(rz_mtu3_pwm, period_cycles); + + /* + * Prescalar is shared by multiple channels, so prescale can + * NOT be modified when there are multiple channels in use with + * different settings. Modify prescalar if other PWM is off or handle + * it, if current prescale value is less than the one we want to set. + */ + if (rz_mtu3_pwm->enable_count[ch] > 1) { + if (rz_mtu3_pwm->prescale[ch] > prescale) + return -EBUSY; + + prescale = rz_mtu3_pwm->prescale[ch]; + } + + pv = rz_mtu3_pwm_calculate_pv_or_dc(period_cycles, prescale); + + duty_cycles = mul_u64_u32_div(state->duty_cycle, rz_mtu3_pwm->rate, + NSEC_PER_SEC); + dc = rz_mtu3_pwm_calculate_pv_or_dc(duty_cycles, prescale); + + /* + * 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(chip->dev); + + val = RZ_MTU3_TCR_CKEG_RISING | prescale; + + /* Counter must be stopped while updating TCR register */ + if (rz_mtu3_pwm->prescale[ch] != prescale && rz_mtu3_pwm->enable_count[ch]) + rz_mtu3_disable(priv->mtu); + + if (priv->map->base_pwm_number == pwm->hwpwm) { + rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TCR, + RZ_MTU3_TCR_CCLR_TGRA | val); + rz_mtu3_pwm_write_tgr_registers(priv, RZ_MTU3_TGRA, pv, + RZ_MTU3_TGRB, dc); + } else { + rz_mtu3_8bit_ch_write(priv->mtu, RZ_MTU3_TCR, + RZ_MTU3_TCR_CCLR_TGRC | val); + rz_mtu3_pwm_write_tgr_registers(priv, RZ_MTU3_TGRC, pv, + RZ_MTU3_TGRD, dc); + } + + if (rz_mtu3_pwm->prescale[ch] != prescale) { + /* + * Prescalar is shared by multiple channels, we cache the + * prescalar value from first enabled channel and use the same + * value for both channels. + */ + rz_mtu3_pwm->prescale[ch] = prescale; + + if (rz_mtu3_pwm->enable_count[ch]) + rz_mtu3_enable(priv->mtu); + } + + /* If the PWM is not enabled, turn the clock off again to save power. */ + if (!pwm->state.enabled) + pm_runtime_put(chip->dev); + + return 0; +} + +static int rz_mtu3_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct rz_mtu3_pwm_chip *rz_mtu3_pwm = to_rz_mtu3_pwm_chip(chip); + bool enabled = pwm->state.enabled; + int ret; + + if (state->polarity != PWM_POLARITY_NORMAL) + return -EINVAL; + + if (!state->enabled) { + if (enabled) + rz_mtu3_pwm_disable(rz_mtu3_pwm, pwm); + + return 0; + } + + mutex_lock(&rz_mtu3_pwm->lock); + ret = rz_mtu3_pwm_config(chip, pwm, state); + mutex_unlock(&rz_mtu3_pwm->lock); + if (ret) + return ret; + + if (!enabled) + ret = rz_mtu3_pwm_enable(rz_mtu3_pwm, pwm); + + return ret; +} + +static const struct pwm_ops rz_mtu3_pwm_ops = { + .request = rz_mtu3_pwm_request, + .free = rz_mtu3_pwm_free, + .get_state = rz_mtu3_pwm_get_state, + .apply = rz_mtu3_pwm_apply, + .owner = THIS_MODULE, +}; + +static int rz_mtu3_pwm_pm_runtime_suspend(struct device *dev) +{ + struct rz_mtu3_pwm_chip *rz_mtu3_pwm = dev_get_drvdata(dev); + + clk_disable_unprepare(rz_mtu3_pwm->clk); + + return 0; +} + +static int rz_mtu3_pwm_pm_runtime_resume(struct device *dev) +{ + struct rz_mtu3_pwm_chip *rz_mtu3_pwm = dev_get_drvdata(dev); + + return clk_prepare_enable(rz_mtu3_pwm->clk); +} + +static DEFINE_RUNTIME_DEV_PM_OPS(rz_mtu3_pwm_pm_ops, + rz_mtu3_pwm_pm_runtime_suspend, + rz_mtu3_pwm_pm_runtime_resume, NULL); + +static void rz_mtu3_pwm_pm_disable(void *data) +{ + struct rz_mtu3_pwm_chip *rz_mtu3_pwm = data; + + clk_rate_exclusive_put(rz_mtu3_pwm->clk); + pm_runtime_disable(rz_mtu3_pwm->chip.dev); + pm_runtime_set_suspended(rz_mtu3_pwm->chip.dev); +} + +static int rz_mtu3_pwm_probe(struct platform_device *pdev) +{ + struct rz_mtu3 *parent_ddata = dev_get_drvdata(pdev->dev.parent); + struct rz_mtu3_pwm_chip *rz_mtu3_pwm; + struct device *dev = &pdev->dev; + unsigned int i, j = 0; + int ret; + + rz_mtu3_pwm = devm_kzalloc(&pdev->dev, sizeof(*rz_mtu3_pwm), GFP_KERNEL); + if (!rz_mtu3_pwm) + return -ENOMEM; + + rz_mtu3_pwm->clk = parent_ddata->clk; + + for (i = 0; i < RZ_MTU_NUM_CHANNELS; i++) { + if (i == RZ_MTU3_CHAN_5 || i == RZ_MTU3_CHAN_8) + continue; + + rz_mtu3_pwm->channel_data[j].mtu = &parent_ddata->channels[i]; + rz_mtu3_pwm->channel_data[j].mtu->dev = dev; + rz_mtu3_pwm->channel_data[j].map = &channel_map[j]; + j++; + } + + mutex_init(&rz_mtu3_pwm->lock); + platform_set_drvdata(pdev, rz_mtu3_pwm); + ret = clk_prepare_enable(rz_mtu3_pwm->clk); + if (ret) + return dev_err_probe(dev, ret, "Clock enable failed\n"); + + clk_rate_exclusive_get(rz_mtu3_pwm->clk); + + rz_mtu3_pwm->rate = clk_get_rate(rz_mtu3_pwm->clk); + /* + * Refuse clk rates > 1 GHz to prevent overflow later for computing + * period and duty cycle. + */ + if (rz_mtu3_pwm->rate > NSEC_PER_SEC) { + ret = -EINVAL; + clk_rate_exclusive_put(rz_mtu3_pwm->clk); + goto disable_clock; + } + + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + rz_mtu3_pwm->chip.dev = &pdev->dev; + ret = devm_add_action_or_reset(&pdev->dev, rz_mtu3_pwm_pm_disable, + rz_mtu3_pwm); + if (ret < 0) + return ret; + + rz_mtu3_pwm->chip.ops = &rz_mtu3_pwm_ops; + rz_mtu3_pwm->chip.npwm = RZ_MTU3_MAX_PWM_CHANNELS; + ret = devm_pwmchip_add(&pdev->dev, &rz_mtu3_pwm->chip); + if (ret) + return dev_err_probe(&pdev->dev, ret, "failed to add PWM chip\n"); + + pm_runtime_idle(&pdev->dev); + + return 0; + +disable_clock: + clk_disable_unprepare(rz_mtu3_pwm->clk); + return ret; +} + +static struct platform_driver rz_mtu3_pwm_driver = { + .driver = { + .name = "pwm-rz-mtu3", + .pm = pm_ptr(&rz_mtu3_pwm_pm_ops), + }, + .probe = rz_mtu3_pwm_probe, +}; +module_platform_driver(rz_mtu3_pwm_driver); + +MODULE_AUTHOR("Biju Das "); +MODULE_ALIAS("platform:pwm-rz-mtu3"); +MODULE_DESCRIPTION("Renesas RZ/G2L MTU3a PWM Timer Driver"); +MODULE_LICENSE("GPL"); -- 2.25.1