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Immutable branch between MFD and PWM due for the v4.18 merge window (v2)
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This commit is contained in:
Thierry Reding
commit
91348b1453
@ -19,6 +19,11 @@ Required parameters:
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||||
Optional parameters:
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- resets: Phandle to the parent reset controller.
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See ../reset/st,stm32-rcc.txt
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- dmas: List of phandle to dma channels that can be used for
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this timer instance. There may be up to 7 dma channels.
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- dma-names: List of dma names. Must match 'dmas' property. Valid
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names are: "ch1", "ch2", "ch3", "ch4", "up", "trig",
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"com".
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Optional subnodes:
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- pwm: See ../pwm/pwm-stm32.txt
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@ -44,3 +49,18 @@ Example:
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reg = <0>;
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};
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};
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Example with all dmas:
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timer@40010000 {
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...
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dmas = <&dmamux1 11 0x400 0x0>,
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<&dmamux1 12 0x400 0x0>,
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<&dmamux1 13 0x400 0x0>,
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<&dmamux1 14 0x400 0x0>,
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<&dmamux1 15 0x400 0x0>,
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<&dmamux1 16 0x400 0x0>,
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<&dmamux1 17 0x400 0x0>;
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dma-names = "ch1", "ch2", "ch3", "ch4", "up", "trig", "com";
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...
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child nodes...
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};
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@ -4,16 +4,156 @@
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* Author: Benjamin Gaignard <benjamin.gaignard@st.com>
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*/
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#include <linux/bitfield.h>
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#include <linux/mfd/stm32-timers.h>
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#include <linux/module.h>
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#include <linux/of_platform.h>
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#include <linux/reset.h>
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#define STM32_TIMERS_MAX_REGISTERS 0x3fc
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/* DIER register DMA enable bits */
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static const u32 stm32_timers_dier_dmaen[STM32_TIMERS_MAX_DMAS] = {
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TIM_DIER_CC1DE,
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TIM_DIER_CC2DE,
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TIM_DIER_CC3DE,
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TIM_DIER_CC4DE,
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TIM_DIER_UIE,
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TIM_DIER_TDE,
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TIM_DIER_COMDE
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};
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static void stm32_timers_dma_done(void *p)
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{
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struct stm32_timers_dma *dma = p;
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struct dma_tx_state state;
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enum dma_status status;
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status = dmaengine_tx_status(dma->chan, dma->chan->cookie, &state);
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if (status == DMA_COMPLETE)
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complete(&dma->completion);
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}
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/**
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* stm32_timers_dma_burst_read - Read from timers registers using DMA.
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*
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* Read from STM32 timers registers using DMA on a single event.
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* @dev: reference to stm32_timers MFD device
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* @buf: DMA'able destination buffer
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* @id: stm32_timers_dmas event identifier (ch[1..4], up, trig or com)
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* @reg: registers start offset for DMA to read from (like CCRx for capture)
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* @num_reg: number of registers to read upon each DMA request, starting @reg.
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* @bursts: number of bursts to read (e.g. like two for pwm period capture)
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* @tmo_ms: timeout (milliseconds)
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*/
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int stm32_timers_dma_burst_read(struct device *dev, u32 *buf,
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enum stm32_timers_dmas id, u32 reg,
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unsigned int num_reg, unsigned int bursts,
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unsigned long tmo_ms)
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{
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struct stm32_timers *ddata = dev_get_drvdata(dev);
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unsigned long timeout = msecs_to_jiffies(tmo_ms);
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struct regmap *regmap = ddata->regmap;
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struct stm32_timers_dma *dma = &ddata->dma;
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size_t len = num_reg * bursts * sizeof(u32);
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struct dma_async_tx_descriptor *desc;
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struct dma_slave_config config;
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dma_cookie_t cookie;
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dma_addr_t dma_buf;
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u32 dbl, dba;
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long err;
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int ret;
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/* Sanity check */
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if (id < STM32_TIMERS_DMA_CH1 || id >= STM32_TIMERS_MAX_DMAS)
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return -EINVAL;
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if (!num_reg || !bursts || reg > STM32_TIMERS_MAX_REGISTERS ||
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(reg + num_reg * sizeof(u32)) > STM32_TIMERS_MAX_REGISTERS)
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return -EINVAL;
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if (!dma->chans[id])
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return -ENODEV;
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mutex_lock(&dma->lock);
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/* Select DMA channel in use */
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dma->chan = dma->chans[id];
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dma_buf = dma_map_single(dev, buf, len, DMA_FROM_DEVICE);
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if (dma_mapping_error(dev, dma_buf)) {
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ret = -ENOMEM;
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goto unlock;
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}
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/* Prepare DMA read from timer registers, using DMA burst mode */
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memset(&config, 0, sizeof(config));
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config.src_addr = (dma_addr_t)dma->phys_base + TIM_DMAR;
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config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
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ret = dmaengine_slave_config(dma->chan, &config);
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if (ret)
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goto unmap;
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desc = dmaengine_prep_slave_single(dma->chan, dma_buf, len,
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DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
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if (!desc) {
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ret = -EBUSY;
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goto unmap;
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}
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desc->callback = stm32_timers_dma_done;
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desc->callback_param = dma;
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cookie = dmaengine_submit(desc);
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ret = dma_submit_error(cookie);
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if (ret)
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goto dma_term;
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reinit_completion(&dma->completion);
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dma_async_issue_pending(dma->chan);
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/* Setup and enable timer DMA burst mode */
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dbl = FIELD_PREP(TIM_DCR_DBL, bursts - 1);
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dba = FIELD_PREP(TIM_DCR_DBA, reg >> 2);
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ret = regmap_write(regmap, TIM_DCR, dbl | dba);
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if (ret)
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goto dma_term;
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/* Clear pending flags before enabling DMA request */
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ret = regmap_write(regmap, TIM_SR, 0);
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if (ret)
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goto dcr_clr;
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ret = regmap_update_bits(regmap, TIM_DIER, stm32_timers_dier_dmaen[id],
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stm32_timers_dier_dmaen[id]);
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if (ret)
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goto dcr_clr;
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err = wait_for_completion_interruptible_timeout(&dma->completion,
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timeout);
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if (err == 0)
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ret = -ETIMEDOUT;
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else if (err < 0)
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ret = err;
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regmap_update_bits(regmap, TIM_DIER, stm32_timers_dier_dmaen[id], 0);
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regmap_write(regmap, TIM_SR, 0);
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dcr_clr:
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regmap_write(regmap, TIM_DCR, 0);
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dma_term:
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dmaengine_terminate_all(dma->chan);
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unmap:
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dma_unmap_single(dev, dma_buf, len, DMA_FROM_DEVICE);
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unlock:
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dma->chan = NULL;
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mutex_unlock(&dma->lock);
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return ret;
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}
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EXPORT_SYMBOL_GPL(stm32_timers_dma_burst_read);
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static const struct regmap_config stm32_timers_regmap_cfg = {
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.reg_bits = 32,
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.val_bits = 32,
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.reg_stride = sizeof(u32),
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.max_register = 0x3fc,
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.max_register = STM32_TIMERS_MAX_REGISTERS,
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};
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static void stm32_timers_get_arr_size(struct stm32_timers *ddata)
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@ -27,12 +167,45 @@ static void stm32_timers_get_arr_size(struct stm32_timers *ddata)
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regmap_write(ddata->regmap, TIM_ARR, 0x0);
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}
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static void stm32_timers_dma_probe(struct device *dev,
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struct stm32_timers *ddata)
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{
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int i;
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char name[4];
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init_completion(&ddata->dma.completion);
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mutex_init(&ddata->dma.lock);
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/* Optional DMA support: get valid DMA channel(s) or NULL */
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for (i = STM32_TIMERS_DMA_CH1; i <= STM32_TIMERS_DMA_CH4; i++) {
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snprintf(name, ARRAY_SIZE(name), "ch%1d", i + 1);
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ddata->dma.chans[i] = dma_request_slave_channel(dev, name);
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}
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ddata->dma.chans[STM32_TIMERS_DMA_UP] =
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dma_request_slave_channel(dev, "up");
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ddata->dma.chans[STM32_TIMERS_DMA_TRIG] =
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dma_request_slave_channel(dev, "trig");
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ddata->dma.chans[STM32_TIMERS_DMA_COM] =
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dma_request_slave_channel(dev, "com");
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}
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static void stm32_timers_dma_remove(struct device *dev,
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struct stm32_timers *ddata)
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{
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int i;
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for (i = STM32_TIMERS_DMA_CH1; i < STM32_TIMERS_MAX_DMAS; i++)
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if (ddata->dma.chans[i])
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dma_release_channel(ddata->dma.chans[i]);
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}
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static int stm32_timers_probe(struct platform_device *pdev)
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{
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struct device *dev = &pdev->dev;
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struct stm32_timers *ddata;
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struct resource *res;
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void __iomem *mmio;
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int ret;
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ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
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if (!ddata)
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@ -43,6 +216,9 @@ static int stm32_timers_probe(struct platform_device *pdev)
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if (IS_ERR(mmio))
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return PTR_ERR(mmio);
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/* Timer physical addr for DMA */
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ddata->dma.phys_base = res->start;
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ddata->regmap = devm_regmap_init_mmio_clk(dev, "int", mmio,
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&stm32_timers_regmap_cfg);
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if (IS_ERR(ddata->regmap))
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@ -54,9 +230,29 @@ static int stm32_timers_probe(struct platform_device *pdev)
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stm32_timers_get_arr_size(ddata);
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stm32_timers_dma_probe(dev, ddata);
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platform_set_drvdata(pdev, ddata);
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return devm_of_platform_populate(&pdev->dev);
|
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ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
|
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if (ret)
|
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stm32_timers_dma_remove(dev, ddata);
|
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|
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return ret;
|
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}
|
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|
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static int stm32_timers_remove(struct platform_device *pdev)
|
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{
|
||||
struct stm32_timers *ddata = platform_get_drvdata(pdev);
|
||||
|
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/*
|
||||
* Don't use devm_ here: enfore of_platform_depopulate() happens before
|
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* 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,
|
||||
|
||||
@ -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,
|
||||
|
||||
@ -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
|
||||
|
||||
Loading…
Reference in New Issue
Block a user