@@ -481,6 +481,17 @@ config PWM_ROCKCHIP
Generic PWM framework driver for the PWM controller found on
Rockchip SoCs.
+config PWM_RZG2L_GPT
+ tristate "Renesas RZ/G2L General PWM Timer support"
+ depends on ARCH_RENESAS || COMPILE_TEST
+ depends on HAS_IOMEM
+ help
+ This driver exposes the General 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-rzg2l-gpt.
+
config PWM_SAMSUNG
tristate "Samsung PWM support"
depends on PLAT_SAMSUNG || ARCH_S5PV210 || ARCH_EXYNOS || COMPILE_TEST
@@ -44,6 +44,7 @@ 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-$(CONFIG_PWM_RZG2L_GPT) += pwm-rzg2l-gpt.o
obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o
obj-$(CONFIG_PWM_SIFIVE) += pwm-sifive.o
obj-$(CONFIG_PWM_SL28CPLD) += pwm-sl28cpld.o
new file mode 100644
@@ -0,0 +1,537 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Renesas RZ/G2L General PWM Timer (GPT) driver
+ *
+ * Copyright (C) 2022 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:
+ * - Counter must be stopped before modifying Mode and Prescaler.
+ * - When PWM is disabled, the output is driven to inactive.
+ * - While the hardware supports both polarities, the driver (for now)
+ * only handles normal polarity.
+ * - When both channels are used, disabling the channel on one stops the
+ * other.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/limits.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/pwm.h>
+#include <linux/reset.h>
+#include <linux/time.h>
+
+#define RZG2L_GTCR 0x2c
+#define RZG2L_GTUDDTYC 0x30
+#define RZG2L_GTIOR 0x34
+#define RZG2L_GTBER 0x40
+#define RZG2L_GTCNT 0x48
+#define RZG2L_GTCCRA 0x4c
+#define RZG2L_GTCCRB 0x50
+#define RZG2L_GTPR 0x64
+
+#define RZG2L_GTCR_CST BIT(0)
+#define RZG2L_GTCR_MD GENMASK(18, 16)
+#define RZG2L_GTCR_TPCS GENMASK(26, 24)
+
+#define RZG2L_GTCR_MD_SAW_WAVE_PWM_MODE FIELD_PREP(RZG2L_GTCR_MD, 0)
+
+#define RZG2L_GTUDDTYC_UP BIT(0)
+#define RZG2L_GTUDDTYC_UDF BIT(1)
+#define RZG2L_UP_COUNTING (RZG2L_GTUDDTYC_UP | RZG2L_GTUDDTYC_UDF)
+
+#define RZG2L_GTIOR_GTIOA GENMASK(4, 0)
+#define RZG2L_GTIOR_GTIOB GENMASK(20, 16)
+#define RZG2L_GTIOR_OAE BIT(8)
+#define RZG2L_GTIOR_OBE BIT(24)
+
+#define RZG2L_INIT_OUT_LO_OUT_LO_END_TOGGLE 0x07
+#define RZG2L_INIT_OUT_HI_OUT_HI_END_TOGGLE 0x1b
+
+#define RZG2L_GTIOR_GTIOA_OUT_HI_END_TOGGLE_CMP_MATCH \
+ (RZG2L_INIT_OUT_HI_OUT_HI_END_TOGGLE | RZG2L_GTIOR_OAE)
+#define RZG2L_GTIOR_GTIOA_OUT_LO_END_TOGGLE_CMP_MATCH \
+ (RZG2L_INIT_OUT_LO_OUT_LO_END_TOGGLE | RZG2L_GTIOR_OAE)
+#define RZG2L_GTIOR_GTIOB_OUT_HI_END_TOGGLE_CMP_MATCH \
+ (FIELD_PREP(RZG2L_GTIOR_GTIOB, RZG2L_INIT_OUT_HI_OUT_HI_END_TOGGLE) | RZG2L_GTIOR_OBE)
+#define RZG2L_GTIOR_GTIOB_OUT_LO_END_TOGGLE_CMP_MATCH \
+ (FIELD_PREP(RZG2L_GTIOR_GTIOB, RZG2L_INIT_OUT_LO_OUT_LO_END_TOGGLE) | RZG2L_GTIOR_OBE)
+
+#define RZG2L_GTCCR(i) (0x4c + 4 * (i))
+
+#define RZG2L_MAX_HW_CHANNELS (8)
+#define RZG2L_CHANNELS_PER_IO (2)
+#define RZG2L_MAX_PWM_CHANNELS (RZG2L_MAX_HW_CHANNELS * RZG2L_CHANNELS_PER_IO)
+
+#define RZG2L_IS_IOB(a) ((a) & 0x1)
+#define RZG2L_GET_CH_INDEX(a) ((a) / 2)
+
+#define RZG2L_GET_CH_OFFS(i) (0x100 * (i))
+
+struct rzg2l_gpt_chip {
+ struct pwm_chip chip;
+ void __iomem *mmio;
+ struct reset_control *rstc;
+ struct clk *clk;
+ struct mutex lock;
+ u32 state_period;
+ u32 md_prescale;
+ unsigned long rate;
+ u32 user_count[RZG2L_MAX_HW_CHANNELS];
+};
+
+static inline struct rzg2l_gpt_chip *to_rzg2l_gpt_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct rzg2l_gpt_chip, chip);
+}
+
+static void rzg2l_gpt_write(struct rzg2l_gpt_chip *rzg2l_gpt, u32 reg, u32 data)
+{
+ writel(data, rzg2l_gpt->mmio + reg);
+}
+
+static u32 rzg2l_gpt_read(struct rzg2l_gpt_chip *rzg2l_gpt, u32 reg)
+{
+ return readl(rzg2l_gpt->mmio + reg);
+}
+
+static void rzg2l_gpt_modify(struct rzg2l_gpt_chip *rzg2l_gpt, u32 reg, u32 clr,
+ u32 set)
+{
+ rzg2l_gpt_write(rzg2l_gpt, reg,
+ (rzg2l_gpt_read(rzg2l_gpt, reg) & ~clr) | set);
+}
+
+static u8 rzg2l_gpt_calculate_prescale(struct rzg2l_gpt_chip *rzg2l_gpt,
+ u64 period_cycles)
+{
+ u32 prescaled_period_cycles;
+ u8 prescale;
+
+ prescaled_period_cycles = period_cycles >> 32;
+ if (prescaled_period_cycles >= 256)
+ prescale = 5;
+ else
+ prescale = (fls(prescaled_period_cycles) + 1) / 2;
+
+ return prescale;
+}
+
+static int rzg2l_gpt_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct rzg2l_gpt_chip *rzg2l_gpt = to_rzg2l_gpt_chip(chip);
+ u32 ch_index = RZG2L_GET_CH_INDEX(pwm->hwpwm);
+
+ mutex_lock(&rzg2l_gpt->lock);
+ rzg2l_gpt->user_count[ch_index]++;
+ mutex_unlock(&rzg2l_gpt->lock);
+
+ return 0;
+}
+
+static void rzg2l_gpt_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct rzg2l_gpt_chip *rzg2l_gpt = to_rzg2l_gpt_chip(chip);
+ u32 ch_index = RZG2L_GET_CH_INDEX(pwm->hwpwm);
+
+ mutex_lock(&rzg2l_gpt->lock);
+ rzg2l_gpt->user_count[ch_index]--;
+ mutex_unlock(&rzg2l_gpt->lock);
+}
+
+static bool rzg2l_gpt_is_ch_enabled(struct rzg2l_gpt_chip *rzg2l_gpt, u8 ch)
+{
+ u8 ch_index = RZG2L_GET_CH_INDEX(ch);
+ u32 offs = RZG2L_GET_CH_OFFS(ch_index);
+ bool is_counter_running, is_output_en;
+ u32 val;
+
+ val = rzg2l_gpt_read(rzg2l_gpt, offs + RZG2L_GTCR);
+ is_counter_running = val & RZG2L_GTCR_CST;
+
+ val = rzg2l_gpt_read(rzg2l_gpt, offs + RZG2L_GTIOR);
+ if (RZG2L_IS_IOB(ch))
+ is_output_en = val & RZG2L_GTIOR_OBE;
+ else
+ is_output_en = val & RZG2L_GTIOR_OAE;
+
+ return (is_counter_running && is_output_en);
+}
+
+static int rzg2l_gpt_enable(struct rzg2l_gpt_chip *rzg2l_gpt,
+ struct pwm_device *pwm)
+{
+ u8 ch_index = RZG2L_GET_CH_INDEX(pwm->hwpwm);
+ u32 offs = RZG2L_GET_CH_OFFS(ch_index);
+
+ /* Enable pin output */
+ if (RZG2L_IS_IOB(pwm->hwpwm))
+ rzg2l_gpt_modify(rzg2l_gpt, offs + RZG2L_GTIOR,
+ RZG2L_GTIOR_GTIOB | RZG2L_GTIOR_OBE,
+ RZG2L_GTIOR_GTIOB_OUT_HI_END_TOGGLE_CMP_MATCH);
+ else
+ rzg2l_gpt_modify(rzg2l_gpt, offs + RZG2L_GTIOR,
+ RZG2L_GTIOR_GTIOA | RZG2L_GTIOR_OAE,
+ RZG2L_GTIOR_GTIOA_OUT_HI_END_TOGGLE_CMP_MATCH);
+
+ /* Start count */
+ rzg2l_gpt_modify(rzg2l_gpt, offs + RZG2L_GTCR, 0, RZG2L_GTCR_CST);
+
+ return 0;
+}
+
+static void rzg2l_gpt_disable(struct rzg2l_gpt_chip *rzg2l_gpt,
+ struct pwm_device *pwm)
+{
+ u8 ch_index = RZG2L_GET_CH_INDEX(pwm->hwpwm);
+ u32 offs = RZG2L_GET_CH_OFFS(ch_index);
+
+ /* Disable pin output */
+ if (RZG2L_IS_IOB(pwm->hwpwm))
+ rzg2l_gpt_modify(rzg2l_gpt, offs + RZG2L_GTIOR, RZG2L_GTIOR_OBE, 0);
+ else
+ rzg2l_gpt_modify(rzg2l_gpt, offs + RZG2L_GTIOR, RZG2L_GTIOR_OAE, 0);
+
+ /* Stop count, Output low on GTIOCx pin when counting stops */
+ if (rzg2l_gpt->user_count[ch_index] <= 1)
+ rzg2l_gpt_modify(rzg2l_gpt, offs + RZG2L_GTCR, RZG2L_GTCR_CST, 0);
+}
+
+static bool rzg2l_gpt_cntr_need_stop(struct rzg2l_gpt_chip *rzg2l_gpt, u32 ch,
+ u8 prescale)
+{
+ u8 ch_index = RZG2L_GET_CH_INDEX(ch);
+ u32 offs = RZG2L_GET_CH_OFFS(ch_index);
+ u32 md_prescale;
+ u32 gtber;
+ bool ret;
+
+ md_prescale = rzg2l_gpt_read(rzg2l_gpt, offs + RZG2L_GTCR);
+ md_prescale &= RZG2L_GTCR_MD | RZG2L_GTCR_TPCS;
+
+ rzg2l_gpt->md_prescale = RZG2L_GTCR_MD_SAW_WAVE_PWM_MODE |
+ FIELD_PREP(RZG2L_GTCR_TPCS, prescale);
+
+ gtber = rzg2l_gpt_read(rzg2l_gpt, offs + RZG2L_GTBER);
+
+ if (gtber || md_prescale != rzg2l_gpt->md_prescale)
+ ret = true;
+ else
+ ret = false;
+
+ return ret;
+}
+
+static int rzg2l_gpt_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ struct rzg2l_gpt_chip *rzg2l_gpt = to_rzg2l_gpt_chip(chip);
+ u8 ch_index = RZG2L_GET_CH_INDEX(pwm->hwpwm);
+ u32 offs = RZG2L_GET_CH_OFFS(ch_index);
+ bool is_counter_running;
+ unsigned long pv, dc;
+ u64 period_cycles;
+ u64 duty_cycles;
+ u8 prescale;
+
+ /*
+ * Refuse clk rates > 1 GHz to prevent overflowing the following
+ * calculation.
+ */
+ if (rzg2l_gpt->rate > NSEC_PER_SEC)
+ return -EINVAL;
+
+ duty_cycles = state->duty_cycle;
+ if (!state->enabled)
+ duty_cycles = 0;
+
+ /*
+ * GPT counter is shared by multiple channels, so prescale and period
+ * can NOT be modified when there are multiple channels in use with
+ * different settings.
+ */
+ if (state->period != rzg2l_gpt->state_period &&
+ rzg2l_gpt->user_count[ch_index] > 1)
+ return -EBUSY;
+
+ /*
+ * GPT counter is shared by multiple channels, we cache the period value
+ * from the first enabled channel and use the same value for both
+ * channels.
+ */
+ rzg2l_gpt->state_period = state->period;
+
+ period_cycles = mul_u64_u32_div(state->period, rzg2l_gpt->rate, NSEC_PER_SEC);
+ prescale = rzg2l_gpt_calculate_prescale(rzg2l_gpt, period_cycles);
+
+ if (period_cycles >> (2 * prescale) <= U32_MAX)
+ pv = period_cycles >> (2 * prescale);
+ else
+ pv = U32_MAX;
+
+ duty_cycles = mul_u64_u32_div(duty_cycles, rzg2l_gpt->rate, NSEC_PER_SEC);
+
+ if (duty_cycles >> (2 * prescale) <= U32_MAX)
+ dc = duty_cycles >> (2 * prescale);
+ else
+ dc = U32_MAX;
+
+ /*
+ * Counter must be stopped before modifying mode, prescaler, timer
+ * counter and buffer enable registers. These registers are shared
+ * between both channels. So allow updating these registers only for the
+ * first enabled channel.
+ */
+ if (rzg2l_gpt->user_count[ch_index] <= 1 &&
+ rzg2l_gpt_cntr_need_stop(rzg2l_gpt, pwm->hwpwm, prescale))
+ rzg2l_gpt_modify(rzg2l_gpt,
+ offs + RZG2L_GTCR, RZG2L_GTCR_CST, 0);
+
+ is_counter_running = rzg2l_gpt_read(rzg2l_gpt,
+ offs + RZG2L_GTCR) & RZG2L_GTCR_CST;
+ if (!is_counter_running)
+ /* GPT set operating mode (saw-wave up-counting) */
+ rzg2l_gpt_modify(rzg2l_gpt, offs + RZG2L_GTCR, RZG2L_GTCR_MD,
+ RZG2L_GTCR_MD_SAW_WAVE_PWM_MODE);
+
+ /* Set count direction */
+ rzg2l_gpt_write(rzg2l_gpt, offs + RZG2L_GTUDDTYC, RZG2L_UP_COUNTING);
+ if (!is_counter_running)
+ /* Select count clock */
+ rzg2l_gpt_modify(rzg2l_gpt, offs + RZG2L_GTCR, RZG2L_GTCR_TPCS,
+ FIELD_PREP(RZG2L_GTCR_TPCS, prescale));
+
+ /* Set period */
+ rzg2l_gpt_write(rzg2l_gpt, offs + RZG2L_GTPR, pv);
+
+ /* Set duty cycle */
+ rzg2l_gpt_write(rzg2l_gpt, offs + RZG2L_GTCCR(RZG2L_IS_IOB(pwm->hwpwm)),
+ dc);
+ if (!is_counter_running) {
+ /* Set initial value for counter */
+ rzg2l_gpt_write(rzg2l_gpt, offs + RZG2L_GTCNT, 0);
+
+ /* Set no buffer operation */
+ rzg2l_gpt_write(rzg2l_gpt, offs + RZG2L_GTBER, 0);
+ }
+
+ return 0;
+}
+
+static void rzg2l_gpt_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct rzg2l_gpt_chip *rzg2l_gpt = to_rzg2l_gpt_chip(chip);
+ u32 ch_index = RZG2L_GET_CH_INDEX(pwm->hwpwm);
+ u32 offs = RZG2L_GET_CH_OFFS(ch_index);
+ u8 prescale;
+ u64 tmp;
+ u32 val;
+
+ pm_runtime_get_sync(chip->dev);
+ val = rzg2l_gpt_read(rzg2l_gpt, offs + RZG2L_GTCR);
+ state->enabled = rzg2l_gpt_is_ch_enabled(rzg2l_gpt, pwm->hwpwm);
+ if (state->enabled) {
+ prescale = FIELD_GET(RZG2L_GTCR_TPCS, val);
+
+ val = rzg2l_gpt_read(rzg2l_gpt, offs + RZG2L_GTPR);
+ tmp = NSEC_PER_SEC * (u64)val << (2 * prescale);
+ state->period = DIV_ROUND_UP_ULL(tmp, rzg2l_gpt->rate);
+
+ val = rzg2l_gpt_read(rzg2l_gpt,
+ offs + RZG2L_GTCCR(RZG2L_IS_IOB(pwm->hwpwm)));
+ tmp = NSEC_PER_SEC * (u64)val << (2 * prescale);
+ state->duty_cycle = DIV_ROUND_UP_ULL(tmp, rzg2l_gpt->rate);
+
+ /*
+ * if bootloader sets duty_cycle > period, then set the same
+ * value to period.
+ */
+ if (state->duty_cycle > state->period)
+ state->duty_cycle = state->period;
+ }
+
+ state->polarity = PWM_POLARITY_NORMAL;
+ pm_runtime_put(chip->dev);
+}
+
+static int rzg2l_gpt_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ struct rzg2l_gpt_chip *rzg2l_gpt = to_rzg2l_gpt_chip(chip);
+ struct pwm_state cur_state;
+ bool enabled;
+ int ret;
+
+ cur_state = pwm->state;
+ enabled = cur_state.enabled;
+ if (state->polarity != PWM_POLARITY_NORMAL)
+ return -EINVAL;
+
+ if (!enabled && state->enabled)
+ pm_runtime_get_sync(chip->dev);
+
+ mutex_lock(&rzg2l_gpt->lock);
+ ret = rzg2l_gpt_config(chip, pwm, state);
+ mutex_unlock(&rzg2l_gpt->lock);
+ if (ret && (ret != -EBUSY || state->enabled))
+ goto done;
+
+ if (!state->enabled) {
+ rzg2l_gpt_disable(rzg2l_gpt, pwm);
+ ret = 0;
+ goto done;
+ }
+
+ return rzg2l_gpt_enable(rzg2l_gpt, pwm);
+
+done:
+ if (enabled && !state->enabled)
+ pm_runtime_put(chip->dev);
+ return ret;
+}
+
+static const struct pwm_ops rzg2l_gpt_ops = {
+ .request = rzg2l_gpt_request,
+ .free = rzg2l_gpt_free,
+ .get_state = rzg2l_gpt_get_state,
+ .apply = rzg2l_gpt_apply,
+ .owner = THIS_MODULE,
+};
+
+static const struct of_device_id rzg2l_gpt_of_table[] = {
+ { .compatible = "renesas,rzg2l-gpt", },
+ { /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rzg2l_gpt_of_table);
+
+static int __maybe_unused rzg2l_gpt_pm_runtime_suspend(struct device *dev)
+{
+ struct rzg2l_gpt_chip *rzg2l_gpt = dev_get_drvdata(dev);
+
+ clk_disable_unprepare(rzg2l_gpt->clk);
+
+ return 0;
+}
+
+static int __maybe_unused rzg2l_gpt_pm_runtime_resume(struct device *dev)
+{
+ struct rzg2l_gpt_chip *rzg2l_gpt = dev_get_drvdata(dev);
+
+ clk_prepare_enable(rzg2l_gpt->clk);
+
+ return 0;
+}
+
+static const struct dev_pm_ops rzg2l_gpt_pm_ops = {
+ SET_RUNTIME_PM_OPS(rzg2l_gpt_pm_runtime_suspend, rzg2l_gpt_pm_runtime_resume, NULL)
+};
+
+static void rzg2l_gpt_reset_assert_pm_disable(void *data)
+{
+ struct rzg2l_gpt_chip *rzg2l_gpt = data;
+
+ pm_runtime_disable(rzg2l_gpt->chip.dev);
+ pm_runtime_set_suspended(rzg2l_gpt->chip.dev);
+ reset_control_assert(rzg2l_gpt->rstc);
+}
+
+static int rzg2l_gpt_probe(struct platform_device *pdev)
+{
+ DECLARE_BITMAP(ch_en_bits, RZG2L_MAX_PWM_CHANNELS);
+ struct rzg2l_gpt_chip *rzg2l_gpt;
+ int ret;
+ u32 i;
+
+ rzg2l_gpt = devm_kzalloc(&pdev->dev, sizeof(*rzg2l_gpt), GFP_KERNEL);
+ if (!rzg2l_gpt)
+ return -ENOMEM;
+
+ rzg2l_gpt->mmio = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(rzg2l_gpt->mmio))
+ return PTR_ERR(rzg2l_gpt->mmio);
+
+ rzg2l_gpt->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+ if (IS_ERR(rzg2l_gpt->rstc))
+ return dev_err_probe(&pdev->dev, PTR_ERR(rzg2l_gpt->rstc),
+ "get reset failed\n");
+
+ rzg2l_gpt->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(rzg2l_gpt->clk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(rzg2l_gpt->clk),
+ "cannot get clock\n");
+
+ ret = reset_control_deassert(rzg2l_gpt->rstc);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret,
+ "cannot deassert reset control\n");
+
+ rzg2l_gpt->rate = clk_get_rate(rzg2l_gpt->clk);
+
+ clk_prepare_enable(rzg2l_gpt->clk);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ ret = devm_add_action_or_reset(&pdev->dev,
+ rzg2l_gpt_reset_assert_pm_disable,
+ rzg2l_gpt);
+ if (ret < 0)
+ goto clk_disable;
+
+ mutex_init(&rzg2l_gpt->lock);
+ platform_set_drvdata(pdev, rzg2l_gpt);
+
+ /*
+ * We need to keep the clock on, in case the bootloader has enabled the
+ * PWM and is running during probe().
+ */
+ *ch_en_bits = 0;
+ for (i = 0; i < RZG2L_MAX_PWM_CHANNELS; i++) {
+ if (rzg2l_gpt_is_ch_enabled(rzg2l_gpt, i)) {
+ set_bit(i, ch_en_bits);
+ pm_runtime_get_sync(&pdev->dev);
+ }
+ }
+
+ rzg2l_gpt->chip.dev = &pdev->dev;
+ rzg2l_gpt->chip.ops = &rzg2l_gpt_ops;
+ rzg2l_gpt->chip.npwm = RZG2L_MAX_PWM_CHANNELS;
+
+ ret = devm_pwmchip_add(&pdev->dev, &rzg2l_gpt->chip);
+ if (ret) {
+ for (i = 0; i < RZG2L_MAX_PWM_CHANNELS; i++) {
+ if (test_bit(i, ch_en_bits))
+ pm_runtime_put(&pdev->dev);
+ }
+
+ dev_err_probe(&pdev->dev, ret, "failed to add PWM chip\n");
+ goto clk_disable;
+ }
+
+ return 0;
+
+clk_disable:
+ clk_disable_unprepare(rzg2l_gpt->clk);
+ return ret;
+}
+
+static struct platform_driver rzg2l_gpt_driver = {
+ .driver = {
+ .name = "pwm-rzg2l-gpt",
+ .pm = &rzg2l_gpt_pm_ops,
+ .of_match_table = of_match_ptr(rzg2l_gpt_of_table),
+ },
+ .probe = rzg2l_gpt_probe,
+};
+module_platform_driver(rzg2l_gpt_driver);
+
+MODULE_AUTHOR("Biju Das <biju.das.jz@bp.renesas.com>");
+MODULE_DESCRIPTION("Renesas RZ/G2L General PWM Timer (GPT) Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pwm-rzg2l-gpt");
RZ/G2L General PWM Timer (GPT) composed of 8 channels with 32-bit timer (GPT32E). It supports the following functions * 32 bits × 8 channels * Up-counting or down-counting (saw waves) or up/down-counting (triangle waves) for each counter. * Clock sources independently selectable for each channel * Two I/O pins per channel * Two output compare/input capture registers per channel * For the two output compare/input capture registers of each channel, four registers are provided as buffer registers and are capable of operating as comparison registers when buffering is not in use. * In output compare operation, buffer switching can be at crests or troughs, enabling the generation of laterally asymmetric PWM waveforms. * Registers for setting up frame cycles in each channel (with capability for generating interrupts at overflow or underflow) * Generation of dead times in PWM operation * Synchronous starting, stopping and clearing counters for arbitrary channels * Starting, stopping, clearing and up/down counters in response to input level comparison * Starting, clearing, stopping and up/down counters in response to a maximum of four external triggers * Output pin disable function by dead time error and detected short-circuits between output pins * A/D converter start triggers can be generated (GPT32E0 to GPT32E3) * Enables the noise filter for input capture and external trigger operation This patch adds basic pwm support for RZ/G2L GPT driver by creating separate logical channels for each IOs. Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> --- v9->v10: * Updated the error handling in probe(), clk_disable_unprepare called on the error path. * Removed ch_en array and started using bitmask instead. v8->v9: * deassert after devm_clk_get() to avoid reset stays deasserted,in case clk_get() fails. * Removed ch_offs from struct rzg2l_gpt_chip and use macro instead. * Updated error handling in probe() v7->v8: * Modelled as single PWM device handling multiple channels * Replaced shared reset->devm_reset_control_get_exclusive() * Replaced iowrite32->writel and ioread32->readl * Updated prescale calculation * Added PM runtime callbacks * Updated PM handling and removed "pwm_enabled_by_bootloader" variable * Introduced rzg2l_gpt_is_ch_enabled for checking enable status on both IO's * Moved enable/disable output pins from config->enable/disable. * Added rzg2l_gpt_cntr_need_stop() for caching prescalar/mode values. v6->v7: * Added the comment for cacheing rzg2l_gpt->state_period. * Fixed boundary values for pv and dc. * Added comment for modifying mode, prescaler, timer counter and buffer enable registers. * Fixed buffer overflow in get_state() * Removed unnecessary assignment of state->period value in get_state(). * Fixed state->duty_cycle value in get_state(). * Added a limitation for disabling the channels. v5->v6: * Updated macros RZG2L_GTIOR_GTIOB_OUT_HI_END_TOGGLE_CMP_MATCH and RZG2L_GTIOR_GTIOB_OUT_LO_END_TOGGLE_CMP_MATCH with computation involving FIELD_PREP macro. * Removed struct rzg2l_gpt_phase and started using RZG2L_GTCCR macro for duty_offset. * replaced misnomer real_period->state_period. * Added handling for values >= (1024 << 32) for both period and duty cycle. * Added comments for pwm {en,dis}abled by bootloader during probe. v4->v5: * Added Hardware manual details * Replaced the comment GTCNT->Counter * Removed the macros RZG2L_GPT_IO_PER_CHANNEL and chip.npwm directly used in probe. * Removed the unsed macro RZG2L_GTPR_MAX_VALUE * Added driver prefix for the type name and the variable. * Initialization of per_channel data moved from request->probe. * Updated clr parameter for rzg2l_gpt_modify for Start count. * Started using mutex and usage_count for handling shared period and prescalar for the 2 channels. * Updated the comment cycle->period. * Removed clk_disable from rzg2l_gpt_reset_assert_pm_disable() * Replaced pc->rzg2l_gpt. * Updated prescale calculation. * Moved pm_runtime_{get_sync,put} from {request,free}->{enable,disable} * Removed platform_set_drvdata as it is unused * Removed the variable pwm_enabled_by_bootloader * Added dev_err_probe in various error paths in probe. * Added an error message, if devm_pwmchip_add() fails. v3->v4: * Changed the local variable type i from u16->u8 and prescaled_period_ cycles from u64->u32 in calculate_prescale(). * Replaced mul_u64_u64_div_u64()->mul_u64_u32_div() * Dropped the comma after the sentinel. * Add a variable to track pwm enabled by bootloader and added comments in probe(). * Removed unnecessary rzg2l_gpt_reset_assert_pm_disable() from probe. * Replaced devm_clk_get()->devm_clk_get_prepared() * Removed devm_clk_get_optional_enabled() v2->v3: * Updated limitation section * Added prefix "RZG2L_" for all macros * Modified prescale calculation * Removed pwm_set_chip_data * Updated comment related to modifying Mode and Prescaler * Updated setting of prescale value in rzg2l_gpt_config() * Removed else branch from rzg2l_gpt_get_state() * removed the err label from rzg2l_gpt_apply() * Added devm_clk_get_optional_enabled() to retain clk on status, in case bootloader turns on the clk of pwm. * Replaced devm_reset_control_get_exclusive->devm_reset_control_get_shared as single reset shared between 8 channels. v1->v2: * Added Limitations section * dropped "_MASK" from the define names. * used named initializer for struct phase * Added gpt_pwm_device into a flexible array member in rzg2l_gpt_chip * Revised the logic for prescale * Added .get_state callback * Improved error handling in rzg2l_gpt_apply * Removed .remove callback * Tested driver with PWM_DEBUG enabled RFC->V1: * Updated macros * replaced rzg2l_gpt_write_mask()->rzg2l_gpt_modify() * Added rzg2l_gpt_read() --- drivers/pwm/Kconfig | 11 + drivers/pwm/Makefile | 1 + drivers/pwm/pwm-rzg2l-gpt.c | 537 ++++++++++++++++++++++++++++++++++++ 3 files changed, 549 insertions(+) create mode 100644 drivers/pwm/pwm-rzg2l-gpt.c