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>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
---
v17->v17 Resend:
* Added Rb tag from Uwe.
* Rebased against Linux 6.4-rc1
* Updated base-commit and dropped prerequisite patches.
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-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 <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: ac9a78681b921877518763ba0e89202254349d1b
--
2.25.1
