Merge tag 'ib-mfd-pwm-v4.18-1' of... (91348b14) · Commits · EulixOS / Software / Kernel

Documentation/devicetree/bindings/mfd/stm32-timers.txt

+20 −0

Original line number	Diff line number	Diff line
		@@ -19,6 +19,11 @@ Required parameters:
		Optional parameters:
		- resets: Phandle to the parent reset controller.
		See ../reset/st,stm32-rcc.txt
		- dmas: List of phandle to dma channels that can be used for
		this timer instance. There may be up to 7 dma channels.
		- dma-names: List of dma names. Must match 'dmas' property. Valid
		names are: "ch1", "ch2", "ch3", "ch4", "up", "trig",
		"com".

		Optional subnodes:
		- pwm: See ../pwm/pwm-stm32.txt
		@@ -44,3 +49,18 @@ Example:
		reg = <0>;
		};
		};

		Example with all dmas:
		timer@40010000 {
		...
		dmas = <&dmamux1 11 0x400 0x0>,
		<&dmamux1 12 0x400 0x0>,
		<&dmamux1 13 0x400 0x0>,
		<&dmamux1 14 0x400 0x0>,
		<&dmamux1 15 0x400 0x0>,
		<&dmamux1 16 0x400 0x0>,
		<&dmamux1 17 0x400 0x0>;
		dma-names = "ch1", "ch2", "ch3", "ch4", "up", "trig", "com";
		...
		child nodes...
		};

drivers/mfd/stm32-timers.c

+199 −2

Original line number	Diff line number	Diff line
		@@ -4,16 +4,156 @@
		* Author: Benjamin Gaignard <benjamin.gaignard@st.com>
		*/

		#include <linux/bitfield.h>
		#include <linux/mfd/stm32-timers.h>
		#include <linux/module.h>
		#include <linux/of_platform.h>
		#include <linux/reset.h>

		#define STM32_TIMERS_MAX_REGISTERS 0x3fc

		/* DIER register DMA enable bits */
		static const u32 stm32_timers_dier_dmaen[STM32_TIMERS_MAX_DMAS] = {
		TIM_DIER_CC1DE,
		TIM_DIER_CC2DE,
		TIM_DIER_CC3DE,
		TIM_DIER_CC4DE,
		TIM_DIER_UIE,
		TIM_DIER_TDE,
		TIM_DIER_COMDE
		};

		static void stm32_timers_dma_done(void *p)
		{
		struct stm32_timers_dma *dma = p;
		struct dma_tx_state state;
		enum dma_status status;

		status = dmaengine_tx_status(dma->chan, dma->chan->cookie, &state);
		if (status == DMA_COMPLETE)
		complete(&dma->completion);
		}

		/**
		* stm32_timers_dma_burst_read - Read from timers registers using DMA.
		*
		* Read from STM32 timers registers using DMA on a single event.
		* @dev: reference to stm32_timers MFD device
		* @buf: DMA'able destination buffer
		* @id: stm32_timers_dmas event identifier (ch[1..4], up, trig or com)
		* @reg: registers start offset for DMA to read from (like CCRx for capture)
		* @num_reg: number of registers to read upon each DMA request, starting @reg.
		* @bursts: number of bursts to read (e.g. like two for pwm period capture)
		* @tmo_ms: timeout (milliseconds)
		*/
		int stm32_timers_dma_burst_read(struct device dev, u32 buf,
		enum stm32_timers_dmas id, u32 reg,
		unsigned int num_reg, unsigned int bursts,
		unsigned long tmo_ms)
		{
		struct stm32_timers *ddata = dev_get_drvdata(dev);
		unsigned long timeout = msecs_to_jiffies(tmo_ms);
		struct regmap *regmap = ddata->regmap;
		struct stm32_timers_dma *dma = &ddata->dma;
		size_t len = num_reg * bursts * sizeof(u32);
		struct dma_async_tx_descriptor *desc;
		struct dma_slave_config config;
		dma_cookie_t cookie;
		dma_addr_t dma_buf;
		u32 dbl, dba;
		long err;
		int ret;

		/* Sanity check */
		if (id < STM32_TIMERS_DMA_CH1 \|\| id >= STM32_TIMERS_MAX_DMAS)
		return -EINVAL;

		if (!num_reg \|\| !bursts \|\| reg > STM32_TIMERS_MAX_REGISTERS \|\|
		(reg + num_reg * sizeof(u32)) > STM32_TIMERS_MAX_REGISTERS)
		return -EINVAL;

		if (!dma->chans[id])
		return -ENODEV;
		mutex_lock(&dma->lock);

		/* Select DMA channel in use */
		dma->chan = dma->chans[id];
		dma_buf = dma_map_single(dev, buf, len, DMA_FROM_DEVICE);
		if (dma_mapping_error(dev, dma_buf)) {
		ret = -ENOMEM;
		goto unlock;
		}

		/* Prepare DMA read from timer registers, using DMA burst mode */
		memset(&config, 0, sizeof(config));
		config.src_addr = (dma_addr_t)dma->phys_base + TIM_DMAR;
		config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
		ret = dmaengine_slave_config(dma->chan, &config);
		if (ret)
		goto unmap;

		desc = dmaengine_prep_slave_single(dma->chan, dma_buf, len,
		DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
		if (!desc) {
		ret = -EBUSY;
		goto unmap;
		}

		desc->callback = stm32_timers_dma_done;
		desc->callback_param = dma;
		cookie = dmaengine_submit(desc);
		ret = dma_submit_error(cookie);
		if (ret)
		goto dma_term;

		reinit_completion(&dma->completion);
		dma_async_issue_pending(dma->chan);

		/* Setup and enable timer DMA burst mode */
		dbl = FIELD_PREP(TIM_DCR_DBL, bursts - 1);
		dba = FIELD_PREP(TIM_DCR_DBA, reg >> 2);
		ret = regmap_write(regmap, TIM_DCR, dbl \| dba);
		if (ret)
		goto dma_term;

		/* Clear pending flags before enabling DMA request */
		ret = regmap_write(regmap, TIM_SR, 0);
		if (ret)
		goto dcr_clr;

		ret = regmap_update_bits(regmap, TIM_DIER, stm32_timers_dier_dmaen[id],
		stm32_timers_dier_dmaen[id]);
		if (ret)
		goto dcr_clr;

		err = wait_for_completion_interruptible_timeout(&dma->completion,
		timeout);
		if (err == 0)
		ret = -ETIMEDOUT;
		else if (err < 0)
		ret = err;

		regmap_update_bits(regmap, TIM_DIER, stm32_timers_dier_dmaen[id], 0);
		regmap_write(regmap, TIM_SR, 0);
		dcr_clr:
		regmap_write(regmap, TIM_DCR, 0);
		dma_term:
		dmaengine_terminate_all(dma->chan);
		unmap:
		dma_unmap_single(dev, dma_buf, len, DMA_FROM_DEVICE);
		unlock:
		dma->chan = NULL;
		mutex_unlock(&dma->lock);

		return ret;
		}
		EXPORT_SYMBOL_GPL(stm32_timers_dma_burst_read);

		static const struct regmap_config stm32_timers_regmap_cfg = {
		.reg_bits = 32,
		.val_bits = 32,
		.reg_stride = sizeof(u32),
		.max_register = 0x3fc,
		.max_register = STM32_TIMERS_MAX_REGISTERS,
		};

		static void stm32_timers_get_arr_size(struct stm32_timers *ddata)
		@@ -27,12 +167,45 @@ static void stm32_timers_get_arr_size(struct stm32_timers *ddata)
		regmap_write(ddata->regmap, TIM_ARR, 0x0);
		}

		static void stm32_timers_dma_probe(struct device *dev,
		struct stm32_timers *ddata)
		{
		int i;
		char name[4];

		init_completion(&ddata->dma.completion);
		mutex_init(&ddata->dma.lock);

		/* Optional DMA support: get valid DMA channel(s) or NULL */
		for (i = STM32_TIMERS_DMA_CH1; i <= STM32_TIMERS_DMA_CH4; i++) {
		snprintf(name, ARRAY_SIZE(name), "ch%1d", i + 1);
		ddata->dma.chans[i] = dma_request_slave_channel(dev, name);
		}
		ddata->dma.chans[STM32_TIMERS_DMA_UP] =
		dma_request_slave_channel(dev, "up");
		ddata->dma.chans[STM32_TIMERS_DMA_TRIG] =
		dma_request_slave_channel(dev, "trig");
		ddata->dma.chans[STM32_TIMERS_DMA_COM] =
		dma_request_slave_channel(dev, "com");
		}

		static void stm32_timers_dma_remove(struct device *dev,
		struct stm32_timers *ddata)
		{
		int i;

		for (i = STM32_TIMERS_DMA_CH1; i < STM32_TIMERS_MAX_DMAS; i++)
		if (ddata->dma.chans[i])
		dma_release_channel(ddata->dma.chans[i]);
		}

		static int stm32_timers_probe(struct platform_device *pdev)
		{
		struct device *dev = &pdev->dev;
		struct stm32_timers *ddata;
		struct resource *res;
		void __iomem *mmio;
		int ret;

		ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
		if (!ddata)
		@@ -43,6 +216,9 @@ static int stm32_timers_probe(struct platform_device *pdev)
		if (IS_ERR(mmio))
		return PTR_ERR(mmio);

		/* Timer physical addr for DMA */
		ddata->dma.phys_base = res->start;

		ddata->regmap = devm_regmap_init_mmio_clk(dev, "int", mmio,
		&stm32_timers_regmap_cfg);
		if (IS_ERR(ddata->regmap))
		@@ -54,9 +230,29 @@ static int stm32_timers_probe(struct platform_device *pdev)

		stm32_timers_get_arr_size(ddata);

		stm32_timers_dma_probe(dev, ddata);

		platform_set_drvdata(pdev, ddata);

		return devm_of_platform_populate(&pdev->dev);
		ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
		if (ret)
		stm32_timers_dma_remove(dev, ddata);

		return ret;
		}

		static int stm32_timers_remove(struct platform_device *pdev)
		{
		struct stm32_timers *ddata = platform_get_drvdata(pdev);

		/*
		* Don't use devm_ here: enfore of_platform_depopulate() happens before
		* DMA are released, to avoid race on DMA.
		*/
		of_platform_depopulate(&pdev->dev);
		stm32_timers_dma_remove(&pdev->dev, ddata);

		return 0;
		}

		static const struct of_device_id stm32_timers_of_match[] = {
		@@ -67,6 +263,7 @@ MODULE_DEVICE_TABLE(of, stm32_timers_of_match);

		static struct platform_driver stm32_timers_driver = {
		.probe = stm32_timers_probe,
		.remove = stm32_timers_remove,
		.driver = {
		.name = "stm32-timers",
		.of_match_table = stm32_timers_of_match,

drivers/pwm/pwm-stm32.c

+257 −0

Original line number	Diff line number	Diff line
		@@ -8,6 +8,7 @@
		* pwm-atmel.c from Bo Shen
		*/

		#include <linux/bitfield.h>
		#include <linux/mfd/stm32-timers.h>
		#include <linux/module.h>
		#include <linux/of.h>
		@@ -25,6 +26,7 @@ struct stm32_pwm {
		struct regmap *regmap;
		u32 max_arr;
		bool have_complementary_output;
		u32 capture[4] ____cacheline_aligned; /* DMA'able buffer */
		};

		struct stm32_breakinput {
		@@ -62,6 +64,258 @@ static int write_ccrx(struct stm32_pwm *dev, int ch, u32 value)
		return -EINVAL;
		}

		#define TIM_CCER_CC12P (TIM_CCER_CC1P \| TIM_CCER_CC2P)
		#define TIM_CCER_CC12E (TIM_CCER_CC1E \| TIM_CCER_CC2E)
		#define TIM_CCER_CC34P (TIM_CCER_CC3P \| TIM_CCER_CC4P)
		#define TIM_CCER_CC34E (TIM_CCER_CC3E \| TIM_CCER_CC4E)

		/*
		* Capture using PWM input mode:
		* ___ ___
		* TI[1, 2, 3 or 4]: ........._\| \|________\|
		* ^0 ^1 ^2
		* . . .
		* . . XXXXX
		* . . XXXXX \|
		* . XXXXX . \|
		* XXXXX . . \|
		* COUNTER: ______XXXXX . . . \|_XXX
		* start^ . . . ^stop
		* . . . .
		* v v . v
		* v
		* CCR1/CCR3: tx..........t0...........t2
		* CCR2/CCR4: tx..............t1.........
		*
		* DMA burst transfer: \| \|
		* v v
		* DMA buffer: { t0, tx } { t2, t1 }
		* DMA done: ^
		*
		* 0: IC1/3 snapchot on rising edge: counter value -> CCR1/CCR3
		* + DMA transfer CCR[1/3] & CCR[2/4] values (t0, tx: doesn't care)
		* 1: IC2/4 snapchot on falling edge: counter value -> CCR2/CCR4
		* 2: IC1/3 snapchot on rising edge: counter value -> CCR1/CCR3
		* + DMA transfer CCR[1/3] & CCR[2/4] values (t2, t1)
		*
		* DMA done, compute:
		* - Period = t2 - t0
		* - Duty cycle = t1 - t0
		*/
		static int stm32_pwm_raw_capture(struct stm32_pwm priv, struct pwm_device pwm,
		unsigned long tmo_ms, u32 *raw_prd,
		u32 *raw_dty)
		{
		struct device *parent = priv->chip.dev->parent;
		enum stm32_timers_dmas dma_id;
		u32 ccen, ccr;
		int ret;

		/* Ensure registers have been updated, enable counter and capture */
		regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG);
		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, TIM_CR1_CEN);

		/* Use cc1 or cc3 DMA resp for PWM input channels 1 & 2 or 3 & 4 */
		dma_id = pwm->hwpwm < 2 ? STM32_TIMERS_DMA_CH1 : STM32_TIMERS_DMA_CH3;
		ccen = pwm->hwpwm < 2 ? TIM_CCER_CC12E : TIM_CCER_CC34E;
		ccr = pwm->hwpwm < 2 ? TIM_CCR1 : TIM_CCR3;
		regmap_update_bits(priv->regmap, TIM_CCER, ccen, ccen);

		/*
		* Timer DMA burst mode. Request 2 registers, 2 bursts, to get both
		* CCR1 & CCR2 (or CCR3 & CCR4) on each capture event.
		* We'll get two capture snapchots: { CCR1, CCR2 }, { CCR1, CCR2 }
		* or { CCR3, CCR4 }, { CCR3, CCR4 }
		*/
		ret = stm32_timers_dma_burst_read(parent, priv->capture, dma_id, ccr, 2,
		2, tmo_ms);
		if (ret)
		goto stop;

		/* Period: t2 - t0 (take care of counter overflow) */
		if (priv->capture[0] <= priv->capture[2])
		*raw_prd = priv->capture[2] - priv->capture[0];
		else
		*raw_prd = priv->max_arr - priv->capture[0] + priv->capture[2];

		/* Duty cycle capture requires at least two capture units */
		if (pwm->chip->npwm < 2)
		*raw_dty = 0;
		else if (priv->capture[0] <= priv->capture[3])
		*raw_dty = priv->capture[3] - priv->capture[0];
		else
		*raw_dty = priv->max_arr - priv->capture[0] + priv->capture[3];

		if (raw_dty > raw_prd) {
		/*
		* Race beetween PWM input and DMA: it may happen
		* falling edge triggers new capture on TI2/4 before DMA
		* had a chance to read CCR2/4. It means capture[1]
		* contains period + duty_cycle. So, subtract period.
		*/
		raw_dty -= raw_prd;
		}

		stop:
		regmap_update_bits(priv->regmap, TIM_CCER, ccen, 0);
		regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);

		return ret;
		}

		static int stm32_pwm_capture(struct pwm_chip chip, struct pwm_device pwm,
		struct pwm_capture *result, unsigned long tmo_ms)
		{
		struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
		unsigned long long prd, div, dty;
		unsigned long rate;
		unsigned int psc = 0, icpsc, scale;
		u32 raw_prd, raw_dty;
		int ret = 0;

		mutex_lock(&priv->lock);

		if (active_channels(priv)) {
		ret = -EBUSY;
		goto unlock;
		}

		ret = clk_enable(priv->clk);
		if (ret) {
		dev_err(priv->chip.dev, "failed to enable counter clock\n");
		goto unlock;
		}

		rate = clk_get_rate(priv->clk);
		if (!rate) {
		ret = -EINVAL;
		goto clk_dis;
		}

		/* prescaler: fit timeout window provided by upper layer */
		div = (unsigned long long)rate * (unsigned long long)tmo_ms;
		do_div(div, MSEC_PER_SEC);
		prd = div;
		while ((div > priv->max_arr) && (psc < MAX_TIM_PSC)) {
		psc++;
		div = prd;
		do_div(div, psc + 1);
		}
		regmap_write(priv->regmap, TIM_ARR, priv->max_arr);
		regmap_write(priv->regmap, TIM_PSC, psc);

		/* Map TI1 or TI2 PWM input to IC1 & IC2 (or TI3/4 to IC3 & IC4) */
		regmap_update_bits(priv->regmap,
		pwm->hwpwm < 2 ? TIM_CCMR1 : TIM_CCMR2,
		TIM_CCMR_CC1S \| TIM_CCMR_CC2S, pwm->hwpwm & 0x1 ?
		TIM_CCMR_CC1S_TI2 \| TIM_CCMR_CC2S_TI2 :
		TIM_CCMR_CC1S_TI1 \| TIM_CCMR_CC2S_TI1);

		/* Capture period on IC1/3 rising edge, duty cycle on IC2/4 falling. */
		regmap_update_bits(priv->regmap, TIM_CCER, pwm->hwpwm < 2 ?
		TIM_CCER_CC12P : TIM_CCER_CC34P, pwm->hwpwm < 2 ?
		TIM_CCER_CC2P : TIM_CCER_CC4P);

		ret = stm32_pwm_raw_capture(priv, pwm, tmo_ms, &raw_prd, &raw_dty);
		if (ret)
		goto stop;

		/*
		* Got a capture. Try to improve accuracy at high rates:
		* - decrease counter clock prescaler, scale up to max rate.
		* - use input prescaler, capture once every /2 /4 or /8 edges.
		*/
		if (raw_prd) {
		u32 max_arr = priv->max_arr - 0x1000; /* arbitrary margin */

		scale = max_arr / min(max_arr, raw_prd);
		} else {
		scale = priv->max_arr; /* bellow resolution, use max scale */
		}

		if (psc && scale > 1) {
		/* 2nd measure with new scale */
		psc /= scale;
		regmap_write(priv->regmap, TIM_PSC, psc);
		ret = stm32_pwm_raw_capture(priv, pwm, tmo_ms, &raw_prd,
		&raw_dty);
		if (ret)
		goto stop;
		}

		/* Compute intermediate period not to exceed timeout at low rates */
		prd = (unsigned long long)raw_prd * (psc + 1) * NSEC_PER_SEC;
		do_div(prd, rate);

		for (icpsc = 0; icpsc < MAX_TIM_ICPSC ; icpsc++) {
		/* input prescaler: also keep arbitrary margin */
		if (raw_prd >= (priv->max_arr - 0x1000) >> (icpsc + 1))
		break;
		if (prd >= (tmo_ms * NSEC_PER_MSEC) >> (icpsc + 2))
		break;
		}

		if (!icpsc)
		goto done;

		/* Last chance to improve period accuracy, using input prescaler */
		regmap_update_bits(priv->regmap,
		pwm->hwpwm < 2 ? TIM_CCMR1 : TIM_CCMR2,
		TIM_CCMR_IC1PSC \| TIM_CCMR_IC2PSC,
		FIELD_PREP(TIM_CCMR_IC1PSC, icpsc) \|
		FIELD_PREP(TIM_CCMR_IC2PSC, icpsc));

		ret = stm32_pwm_raw_capture(priv, pwm, tmo_ms, &raw_prd, &raw_dty);
		if (ret)
		goto stop;

		if (raw_dty >= (raw_prd >> icpsc)) {
		/*
		* We may fall here using input prescaler, when input
		* capture starts on high side (before falling edge).
		* Example with icpsc to capture on each 4 events:
		*
		* start 1st capture 2nd capture
		* v v v
		* ___ _____ _____ _____ _____ ____
		* TI1..4 \|__\| \|__\| \|__\| \|__\| \|__\|
		* v v . . . . . v v
		* icpsc1/3: . 0 . 1 . 2 . 3 . 0
		* icpsc2/4: 0 1 2 3 0
		* v v v v
		* CCR1/3 ......t0..............................t2
		* CCR2/4 ..t1..............................t1'...
		* . . .
		* Capture0: .<----------------------------->.
		* Capture1: .<-------------------------->. .
		* . . .
		* Period: .<------> . .
		* Low side: .<>.
		*
		* Result:
		* - Period = Capture0 / icpsc
		* - Duty = Period - Low side = Period - (Capture0 - Capture1)
		*/
		raw_dty = (raw_prd >> icpsc) - (raw_prd - raw_dty);
		}

		done:
		prd = (unsigned long long)raw_prd * (psc + 1) * NSEC_PER_SEC;
		result->period = DIV_ROUND_UP_ULL(prd, rate << icpsc);
		dty = (unsigned long long)raw_dty * (psc + 1) * NSEC_PER_SEC;
		result->duty_cycle = DIV_ROUND_UP_ULL(dty, rate);
		stop:
		regmap_write(priv->regmap, TIM_CCER, 0);
		regmap_write(priv->regmap, pwm->hwpwm < 2 ? TIM_CCMR1 : TIM_CCMR2, 0);
		regmap_write(priv->regmap, TIM_PSC, 0);
		clk_dis:
		clk_disable(priv->clk);
		unlock:
		mutex_unlock(&priv->lock);

		return ret;
		}

		static int stm32_pwm_config(struct stm32_pwm *priv, int ch,
		int duty_ns, int period_ns)
		{
		@@ -230,6 +484,9 @@ static int stm32_pwm_apply_locked(struct pwm_chip chip, struct pwm_device pwm,
		static const struct pwm_ops stm32pwm_ops = {
		.owner = THIS_MODULE,
		.apply = stm32_pwm_apply_locked,
		#if IS_ENABLED(CONFIG_DMA_ENGINE)
		.capture = stm32_pwm_capture,
		#endif
		};

		static int stm32_pwm_set_breakinput(struct stm32_pwm *priv,

include/linux/mfd/stm32-timers.h

+58 −0

Original line number	Diff line number	Diff line
		@@ -8,6 +8,8 @@
		#define _LINUX_STM32_GPTIMER_H_

		#include <linux/clk.h>
		#include <linux/dmaengine.h>
		#include <linux/dma-mapping.h>
		#include <linux/regmap.h>

		#define TIM_CR1 0x00 /* Control Register 1 */
		@@ -27,6 +29,8 @@
		#define TIM_CCR3 0x3C /* Capt/Comp Register 3 */
		#define TIM_CCR4 0x40 /* Capt/Comp Register 4 */
		#define TIM_BDTR 0x44 /* Break and Dead-Time Reg */
		#define TIM_DCR 0x48 /* DMA control register */
		#define TIM_DMAR 0x4C /* DMA register for transfer */

		#define TIM_CR1_CEN BIT(0) /* Counter Enable */
		#define TIM_CR1_DIR BIT(4) /* Counter Direction */
		@@ -36,17 +40,35 @@
		#define TIM_SMCR_SMS (BIT(0) \| BIT(1) \| BIT(2)) /* Slave mode selection */
		#define TIM_SMCR_TS (BIT(4) \| BIT(5) \| BIT(6)) /* Trigger selection */
		#define TIM_DIER_UIE BIT(0) /* Update interrupt */
		#define TIM_DIER_UDE BIT(8) /* Update DMA request Enable */
		#define TIM_DIER_CC1DE BIT(9) /* CC1 DMA request Enable */
		#define TIM_DIER_CC2DE BIT(10) /* CC2 DMA request Enable */
		#define TIM_DIER_CC3DE BIT(11) /* CC3 DMA request Enable */
		#define TIM_DIER_CC4DE BIT(12) /* CC4 DMA request Enable */
		#define TIM_DIER_COMDE BIT(13) /* COM DMA request Enable */
		#define TIM_DIER_TDE BIT(14) /* Trigger DMA request Enable */
		#define TIM_SR_UIF BIT(0) /* Update interrupt flag */
		#define TIM_EGR_UG BIT(0) /* Update Generation */
		#define TIM_CCMR_PE BIT(3) /* Channel Preload Enable */
		#define TIM_CCMR_M1 (BIT(6) \| BIT(5)) /* Channel PWM Mode 1 */
		#define TIM_CCMR_CC1S (BIT(0) \| BIT(1)) /* Capture/compare 1 sel */
		#define TIM_CCMR_IC1PSC GENMASK(3, 2) /* Input capture 1 prescaler */
		#define TIM_CCMR_CC2S (BIT(8) \| BIT(9)) /* Capture/compare 2 sel */
		#define TIM_CCMR_IC2PSC GENMASK(11, 10) /* Input capture 2 prescaler */
		#define TIM_CCMR_CC1S_TI1 BIT(0) /* IC1/IC3 selects TI1/TI3 */
		#define TIM_CCMR_CC1S_TI2 BIT(1) /* IC1/IC3 selects TI2/TI4 */
		#define TIM_CCMR_CC2S_TI2 BIT(8) /* IC2/IC4 selects TI2/TI4 */
		#define TIM_CCMR_CC2S_TI1 BIT(9) /* IC2/IC4 selects TI1/TI3 */
		#define TIM_CCER_CC1E BIT(0) /* Capt/Comp 1 out Ena */
		#define TIM_CCER_CC1P BIT(1) /* Capt/Comp 1 Polarity */
		#define TIM_CCER_CC1NE BIT(2) /* Capt/Comp 1N out Ena */
		#define TIM_CCER_CC1NP BIT(3) /* Capt/Comp 1N Polarity */
		#define TIM_CCER_CC2E BIT(4) /* Capt/Comp 2 out Ena */
		#define TIM_CCER_CC2P BIT(5) /* Capt/Comp 2 Polarity */
		#define TIM_CCER_CC3E BIT(8) /* Capt/Comp 3 out Ena */
		#define TIM_CCER_CC3P BIT(9) /* Capt/Comp 3 Polarity */
		#define TIM_CCER_CC4E BIT(12) /* Capt/Comp 4 out Ena */
		#define TIM_CCER_CC4P BIT(13) /* Capt/Comp 4 Polarity */
		#define TIM_CCER_CCXE (BIT(0) \| BIT(4) \| BIT(8) \| BIT(12))
		#define TIM_BDTR_BKE BIT(12) /* Break input enable */
		#define TIM_BDTR_BKP BIT(13) /* Break input polarity */
		@@ -56,8 +78,11 @@
		#define TIM_BDTR_BK2F (BIT(20) \| BIT(21) \| BIT(22) \| BIT(23))
		#define TIM_BDTR_BK2E BIT(24) /* Break 2 input enable */
		#define TIM_BDTR_BK2P BIT(25) /* Break 2 input polarity */
		#define TIM_DCR_DBA GENMASK(4, 0) /* DMA base addr */
		#define TIM_DCR_DBL GENMASK(12, 8) /* DMA burst len */

		#define MAX_TIM_PSC 0xFFFF
		#define MAX_TIM_ICPSC 0x3
		#define TIM_CR2_MMS_SHIFT 4
		#define TIM_CR2_MMS2_SHIFT 20
		#define TIM_SMCR_TS_SHIFT 4
		@@ -65,9 +90,42 @@
		#define TIM_BDTR_BKF_SHIFT 16
		#define TIM_BDTR_BK2F_SHIFT 20

		enum stm32_timers_dmas {
		STM32_TIMERS_DMA_CH1,
		STM32_TIMERS_DMA_CH2,
		STM32_TIMERS_DMA_CH3,
		STM32_TIMERS_DMA_CH4,
		STM32_TIMERS_DMA_UP,
		STM32_TIMERS_DMA_TRIG,
		STM32_TIMERS_DMA_COM,
		STM32_TIMERS_MAX_DMAS,
		};

		/**
		* struct stm32_timers_dma - STM32 timer DMA handling.
		* @completion: end of DMA transfer completion
		* @phys_base: control registers physical base address
		* @lock: protect DMA access
		* @chan: DMA channel in use
		* @chans: DMA channels available for this timer instance
		*/
		struct stm32_timers_dma {
		struct completion completion;
		phys_addr_t phys_base;
		struct mutex lock;
		struct dma_chan *chan;
		struct dma_chan *chans[STM32_TIMERS_MAX_DMAS];
		};

		struct stm32_timers {
		struct clk *clk;
		struct regmap *regmap;
		u32 max_arr;
		struct stm32_timers_dma dma; /* Only to be used by the parent */
		};

		int stm32_timers_dma_burst_read(struct device dev, u32 buf,
		enum stm32_timers_dmas id, u32 reg,
		unsigned int num_reg, unsigned int bursts,
		unsigned long tmo_ms);
		#endif