Hi Uwe,
Gentle ping. Are you happy with this patch?
Cheers,
Biju
> -----Original Message-----
> From: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> Sent: Monday, May 22, 2023 6:15 PM
> To: Thierry Reding <thierry.reding@xxxxxxxxx>
> Cc: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>; Uwe Kleine-König <u.kleine-
> koenig@xxxxxxxxxxxxxx>; linux-pwm@xxxxxxxxxxxxxxx; Geert Uytterhoeven
> <geert+renesas@xxxxxxxxx>; Prabhakar Mahadev Lad <prabhakar.mahadev-
> lad.rj@xxxxxxxxxxxxxx>; linux-renesas-soc@xxxxxxxxxxxxxxx
> Subject: [PATCH v17] pwm: Add Renesas RZ/G2L MTU3a PWM driver
>
> 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 <biju.das.jz@xxxxxxxxxxxxxx>
> ---
> v16->v17:
> * Added a comment related to supported prescalar values in rz_mtu3_pwm_
> calculate_prescale().
> * Replaced pm_runtime_get_sync->pm_runtime_resume_and_get and
> propogated
> the error.
> * Improved the logic in rz_mtu3_pwm_calculate_pv_or_dc() by using
> min(period_or_duty_cycle >> (2 * prescale), (u64)U16_MAX);
> * Updated rz_mtu3_pwm_get_state() by moving duty > period check
> inside the top if block.
> 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 <linux/mfd/rz-mtu3.h>
> * 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 <linux/mfd/rz-mtu3.h> 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 | 551 ++++++++++++++++++++++++++++++++++++++
> 3 files changed, 563 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..bed8bd671e37
> --- /dev/null
> +++ b/drivers/pwm/pwm-rz-mtu3.c
> @@ -0,0 +1,551 @@
> +// 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-use
> +rs-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 <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/limits.h>
> +#include <linux/mfd/rz-mtu3.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/pwm.h>
> +#include <linux/time.h>
> +
> +#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;
> +
> + /*
> + * Supported prescale values are 1, 4, 16 and 64.
> + * TODO: Support prescale values 2, 8, 32, 256 and 1024.
> + */
> + 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);
> + int rc;
> +
> + rc = pm_runtime_resume_and_get(chip->dev);
> + if (rc)
> + return rc;
> +
> + 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 min(period_or_duty_cycle >> (2 * prescale), (u64)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) {
> + int rc;
> +
> + rc = pm_runtime_resume_and_get(chip->dev);
> + if (rc)
> + return rc;
> + }
> +
> + 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 <biju.das.jz@xxxxxxxxxxxxxx>");
> +MODULE_ALIAS("platform:pwm-rz-mtu3");
> +MODULE_DESCRIPTION("Renesas RZ/G2L MTU3a PWM Timer Driver");
> +MODULE_LICENSE("GPL");
>
> base-commit: 9f258af06b6268be8e960f63c3f66e88bdbbbdb0
> prerequisite-patch-id: 7d5c55db908971d16a58eb46b25d42dfb0f680ec
> prerequisite-patch-id: 6c15d33bb612750523d14af87a5cf9e6ff142540
> prerequisite-patch-id: e5e4d86a0a012a59f585b84ce7ae0d3f047787dc
> prerequisite-patch-id: d62b4e1326f1518fd30eb98a37bfb4998573979a
> prerequisite-patch-id: 15bf63b610cab275387a2bbee7ab2a0a48414f75
> --
> 2.25.1
