diff options
Diffstat (limited to 'drivers/iio/adc/stm32-adc.c')
| -rw-r--r-- | drivers/iio/adc/stm32-adc.c | 209 |
1 files changed, 83 insertions, 126 deletions
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index 205e1699f954..80c3f963527b 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -28,115 +28,6 @@ #include "stm32-adc-core.h" -/* STM32F4 - Registers for each ADC instance */ -#define STM32F4_ADC_SR 0x00 -#define STM32F4_ADC_CR1 0x04 -#define STM32F4_ADC_CR2 0x08 -#define STM32F4_ADC_SMPR1 0x0C -#define STM32F4_ADC_SMPR2 0x10 -#define STM32F4_ADC_HTR 0x24 -#define STM32F4_ADC_LTR 0x28 -#define STM32F4_ADC_SQR1 0x2C -#define STM32F4_ADC_SQR2 0x30 -#define STM32F4_ADC_SQR3 0x34 -#define STM32F4_ADC_JSQR 0x38 -#define STM32F4_ADC_JDR1 0x3C -#define STM32F4_ADC_JDR2 0x40 -#define STM32F4_ADC_JDR3 0x44 -#define STM32F4_ADC_JDR4 0x48 -#define STM32F4_ADC_DR 0x4C - -/* STM32F4_ADC_SR - bit fields */ -#define STM32F4_STRT BIT(4) -#define STM32F4_EOC BIT(1) - -/* STM32F4_ADC_CR1 - bit fields */ -#define STM32F4_RES_SHIFT 24 -#define STM32F4_RES_MASK GENMASK(25, 24) -#define STM32F4_SCAN BIT(8) -#define STM32F4_EOCIE BIT(5) - -/* STM32F4_ADC_CR2 - bit fields */ -#define STM32F4_SWSTART BIT(30) -#define STM32F4_EXTEN_SHIFT 28 -#define STM32F4_EXTEN_MASK GENMASK(29, 28) -#define STM32F4_EXTSEL_SHIFT 24 -#define STM32F4_EXTSEL_MASK GENMASK(27, 24) -#define STM32F4_EOCS BIT(10) -#define STM32F4_DDS BIT(9) -#define STM32F4_DMA BIT(8) -#define STM32F4_ADON BIT(0) - -/* STM32H7 - Registers for each ADC instance */ -#define STM32H7_ADC_ISR 0x00 -#define STM32H7_ADC_IER 0x04 -#define STM32H7_ADC_CR 0x08 -#define STM32H7_ADC_CFGR 0x0C -#define STM32H7_ADC_SMPR1 0x14 -#define STM32H7_ADC_SMPR2 0x18 -#define STM32H7_ADC_PCSEL 0x1C -#define STM32H7_ADC_SQR1 0x30 -#define STM32H7_ADC_SQR2 0x34 -#define STM32H7_ADC_SQR3 0x38 -#define STM32H7_ADC_SQR4 0x3C -#define STM32H7_ADC_DR 0x40 -#define STM32H7_ADC_DIFSEL 0xC0 -#define STM32H7_ADC_CALFACT 0xC4 -#define STM32H7_ADC_CALFACT2 0xC8 - -/* STM32H7_ADC_ISR - bit fields */ -#define STM32MP1_VREGREADY BIT(12) -#define STM32H7_EOC BIT(2) -#define STM32H7_ADRDY BIT(0) - -/* STM32H7_ADC_IER - bit fields */ -#define STM32H7_EOCIE STM32H7_EOC - -/* STM32H7_ADC_CR - bit fields */ -#define STM32H7_ADCAL BIT(31) -#define STM32H7_ADCALDIF BIT(30) -#define STM32H7_DEEPPWD BIT(29) -#define STM32H7_ADVREGEN BIT(28) -#define STM32H7_LINCALRDYW6 BIT(27) -#define STM32H7_LINCALRDYW5 BIT(26) -#define STM32H7_LINCALRDYW4 BIT(25) -#define STM32H7_LINCALRDYW3 BIT(24) -#define STM32H7_LINCALRDYW2 BIT(23) -#define STM32H7_LINCALRDYW1 BIT(22) -#define STM32H7_ADCALLIN BIT(16) -#define STM32H7_BOOST BIT(8) -#define STM32H7_ADSTP BIT(4) -#define STM32H7_ADSTART BIT(2) -#define STM32H7_ADDIS BIT(1) -#define STM32H7_ADEN BIT(0) - -/* STM32H7_ADC_CFGR bit fields */ -#define STM32H7_EXTEN_SHIFT 10 -#define STM32H7_EXTEN_MASK GENMASK(11, 10) -#define STM32H7_EXTSEL_SHIFT 5 -#define STM32H7_EXTSEL_MASK GENMASK(9, 5) -#define STM32H7_RES_SHIFT 2 -#define STM32H7_RES_MASK GENMASK(4, 2) -#define STM32H7_DMNGT_SHIFT 0 -#define STM32H7_DMNGT_MASK GENMASK(1, 0) - -enum stm32h7_adc_dmngt { - STM32H7_DMNGT_DR_ONLY, /* Regular data in DR only */ - STM32H7_DMNGT_DMA_ONESHOT, /* DMA one shot mode */ - STM32H7_DMNGT_DFSDM, /* DFSDM mode */ - STM32H7_DMNGT_DMA_CIRC, /* DMA circular mode */ -}; - -/* STM32H7_ADC_CALFACT - bit fields */ -#define STM32H7_CALFACT_D_SHIFT 16 -#define STM32H7_CALFACT_D_MASK GENMASK(26, 16) -#define STM32H7_CALFACT_S_SHIFT 0 -#define STM32H7_CALFACT_S_MASK GENMASK(10, 0) - -/* STM32H7_ADC_CALFACT2 - bit fields */ -#define STM32H7_LINCALFACT_SHIFT 0 -#define STM32H7_LINCALFACT_MASK GENMASK(29, 0) - /* Number of linear calibration shadow registers / LINCALRDYW control bits */ #define STM32H7_LINCALFACT_NUM 6 @@ -211,7 +102,7 @@ struct stm32_adc_calib { }; /** - * stm32_adc_regs - stm32 ADC misc registers & bitfield desc + * struct stm32_adc_regs - stm32 ADC misc registers & bitfield desc * @reg: register offset * @mask: bitfield mask * @shift: left shift @@ -223,10 +114,12 @@ struct stm32_adc_regs { }; /** - * stm32_adc_regspec - stm32 registers definition, compatible dependent data + * struct stm32_adc_regspec - stm32 registers definition * @dr: data register offset * @ier_eoc: interrupt enable register & eocie bitfield + * @ier_ovr: interrupt enable register & overrun bitfield * @isr_eoc: interrupt status register & eoc bitfield + * @isr_ovr: interrupt status register & overrun bitfield * @sqr: reference to sequence registers array * @exten: trigger control register & bitfield * @extsel: trigger selection register & bitfield @@ -237,7 +130,9 @@ struct stm32_adc_regs { struct stm32_adc_regspec { const u32 dr; const struct stm32_adc_regs ier_eoc; + const struct stm32_adc_regs ier_ovr; const struct stm32_adc_regs isr_eoc; + const struct stm32_adc_regs isr_ovr; const struct stm32_adc_regs *sqr; const struct stm32_adc_regs exten; const struct stm32_adc_regs extsel; @@ -249,7 +144,7 @@ struct stm32_adc_regspec { struct stm32_adc; /** - * stm32_adc_cfg - stm32 compatible configuration data + * struct stm32_adc_cfg - stm32 compatible configuration data * @regs: registers descriptions * @adc_info: per instance input channels definitions * @trigs: external trigger sources @@ -292,8 +187,8 @@ struct stm32_adc_cfg { * @rx_buf: dma rx buffer cpu address * @rx_dma_buf: dma rx buffer bus address * @rx_buf_sz: dma rx buffer size - * @difsel bitmask to set single-ended/differential channel - * @pcsel bitmask to preselect channels on some devices + * @difsel: bitmask to set single-ended/differential channel + * @pcsel: bitmask to preselect channels on some devices * @smpr_val: sampling time settings (e.g. smpr1 / smpr2) * @cal: optional calibration data on some devices * @chan_name: channel name array @@ -363,7 +258,7 @@ static const struct stm32_adc_info stm32h7_adc_info = { .num_res = ARRAY_SIZE(stm32h7_adc_resolutions), }; -/** +/* * stm32f4_sq - describe regular sequence registers * - L: sequence len (register & bit field) * - SQ1..SQ16: sequence entries (register & bit field) @@ -410,7 +305,7 @@ static struct stm32_adc_trig_info stm32f4_adc_trigs[] = { {}, /* sentinel */ }; -/** +/* * stm32f4_smp_bits[] - describe sampling time register index & bit fields * Sorted so it can be indexed by channel number. */ @@ -446,7 +341,9 @@ static const unsigned int stm32f4_adc_smp_cycles[STM32_ADC_MAX_SMP + 1] = { static const struct stm32_adc_regspec stm32f4_adc_regspec = { .dr = STM32F4_ADC_DR, .ier_eoc = { STM32F4_ADC_CR1, STM32F4_EOCIE }, + .ier_ovr = { STM32F4_ADC_CR1, STM32F4_OVRIE }, .isr_eoc = { STM32F4_ADC_SR, STM32F4_EOC }, + .isr_ovr = { STM32F4_ADC_SR, STM32F4_OVR }, .sqr = stm32f4_sq, .exten = { STM32F4_ADC_CR2, STM32F4_EXTEN_MASK, STM32F4_EXTEN_SHIFT }, .extsel = { STM32F4_ADC_CR2, STM32F4_EXTSEL_MASK, @@ -501,7 +398,7 @@ static struct stm32_adc_trig_info stm32h7_adc_trigs[] = { {}, }; -/** +/* * stm32h7_smp_bits - describe sampling time register index & bit fields * Sorted so it can be indexed by channel number. */ @@ -538,7 +435,9 @@ static const unsigned int stm32h7_adc_smp_cycles[STM32_ADC_MAX_SMP + 1] = { static const struct stm32_adc_regspec stm32h7_adc_regspec = { .dr = STM32H7_ADC_DR, .ier_eoc = { STM32H7_ADC_IER, STM32H7_EOCIE }, + .ier_ovr = { STM32H7_ADC_IER, STM32H7_OVRIE }, .isr_eoc = { STM32H7_ADC_ISR, STM32H7_EOC }, + .isr_ovr = { STM32H7_ADC_ISR, STM32H7_OVR }, .sqr = stm32h7_sq, .exten = { STM32H7_ADC_CFGR, STM32H7_EXTEN_MASK, STM32H7_EXTEN_SHIFT }, .extsel = { STM32H7_ADC_CFGR, STM32H7_EXTSEL_MASK, @@ -615,6 +514,18 @@ static void stm32_adc_conv_irq_disable(struct stm32_adc *adc) adc->cfg->regs->ier_eoc.mask); } +static void stm32_adc_ovr_irq_enable(struct stm32_adc *adc) +{ + stm32_adc_set_bits(adc, adc->cfg->regs->ier_ovr.reg, + adc->cfg->regs->ier_ovr.mask); +} + +static void stm32_adc_ovr_irq_disable(struct stm32_adc *adc) +{ + stm32_adc_clr_bits(adc, adc->cfg->regs->ier_ovr.reg, + adc->cfg->regs->ier_ovr.mask); +} + static void stm32_adc_set_res(struct stm32_adc *adc) { const struct stm32_adc_regs *res = &adc->cfg->regs->res; @@ -1103,6 +1014,7 @@ static int stm32_adc_conf_scan_seq(struct iio_dev *indio_dev, /** * stm32_adc_get_trig_extsel() - Get external trigger selection + * @indio_dev: IIO device structure * @trig: trigger * * Returns trigger extsel value, if trig matches, -EINVAL otherwise. @@ -1313,6 +1225,19 @@ static int stm32_adc_read_raw(struct iio_dev *indio_dev, } } +static irqreturn_t stm32_adc_threaded_isr(int irq, void *data) +{ + struct stm32_adc *adc = data; + struct iio_dev *indio_dev = iio_priv_to_dev(adc); + const struct stm32_adc_regspec *regs = adc->cfg->regs; + u32 status = stm32_adc_readl(adc, regs->isr_eoc.reg); + + if (status & regs->isr_ovr.mask) + dev_err(&indio_dev->dev, "Overrun, stopping: restart needed\n"); + + return IRQ_HANDLED; +} + static irqreturn_t stm32_adc_isr(int irq, void *data) { struct stm32_adc *adc = data; @@ -1320,6 +1245,19 @@ static irqreturn_t stm32_adc_isr(int irq, void *data) const struct stm32_adc_regspec *regs = adc->cfg->regs; u32 status = stm32_adc_readl(adc, regs->isr_eoc.reg); + if (status & regs->isr_ovr.mask) { + /* + * Overrun occurred on regular conversions: data for wrong + * channel may be read. Unconditionally disable interrupts + * to stop processing data and print error message. + * Restarting the capture can be done by disabling, then + * re-enabling it (e.g. write 0, then 1 to buffer/enable). + */ + stm32_adc_ovr_irq_disable(adc); + stm32_adc_conv_irq_disable(adc); + return IRQ_WAKE_THREAD; + } + if (status & regs->isr_eoc.mask) { /* Reading DR also clears EOC status flag */ adc->buffer[adc->bufi] = stm32_adc_readw(adc, regs->dr); @@ -1406,6 +1344,10 @@ static int stm32_adc_of_xlate(struct iio_dev *indio_dev, /** * stm32_adc_debugfs_reg_access - read or write register value + * @indio_dev: IIO device structure + * @reg: register offset + * @writeval: value to write + * @readval: value to read * * To read a value from an ADC register: * echo [ADC reg offset] > direct_reg_access @@ -1508,7 +1450,7 @@ static int stm32_adc_dma_start(struct iio_dev *indio_dev) cookie = dmaengine_submit(desc); ret = dma_submit_error(cookie); if (ret) { - dmaengine_terminate_all(adc->dma_chan); + dmaengine_terminate_sync(adc->dma_chan); return ret; } @@ -1545,6 +1487,8 @@ static int __stm32_adc_buffer_postenable(struct iio_dev *indio_dev) /* Reset adc buffer index */ adc->bufi = 0; + stm32_adc_ovr_irq_enable(adc); + if (!adc->dma_chan) stm32_adc_conv_irq_enable(adc); @@ -1585,8 +1529,10 @@ static void __stm32_adc_buffer_predisable(struct iio_dev *indio_dev) if (!adc->dma_chan) stm32_adc_conv_irq_disable(adc); + stm32_adc_ovr_irq_disable(adc); + if (adc->dma_chan) - dmaengine_terminate_all(adc->dma_chan); + dmaengine_terminate_sync(adc->dma_chan); if (stm32_adc_set_trig(indio_dev, NULL)) dev_err(&indio_dev->dev, "Can't clear trigger\n"); @@ -1850,9 +1796,21 @@ static int stm32_adc_dma_request(struct iio_dev *indio_dev) struct dma_slave_config config; int ret; - adc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx"); - if (!adc->dma_chan) + adc->dma_chan = dma_request_chan(&indio_dev->dev, "rx"); + if (IS_ERR(adc->dma_chan)) { + ret = PTR_ERR(adc->dma_chan); + if (ret != -ENODEV) { + if (ret != -EPROBE_DEFER) + dev_err(&indio_dev->dev, + "DMA channel request failed with %d\n", + ret); + return ret; + } + + /* DMA is optional: fall back to IRQ mode */ + adc->dma_chan = NULL; return 0; + } adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, STM32_DMA_BUFFER_SIZE, @@ -1919,13 +1877,12 @@ static int stm32_adc_probe(struct platform_device *pdev) } adc->irq = platform_get_irq(pdev, 0); - if (adc->irq < 0) { - dev_err(&pdev->dev, "failed to get irq\n"); + if (adc->irq < 0) return adc->irq; - } - ret = devm_request_irq(&pdev->dev, adc->irq, stm32_adc_isr, - 0, pdev->name, adc); + ret = devm_request_threaded_irq(&pdev->dev, adc->irq, stm32_adc_isr, + stm32_adc_threaded_isr, + 0, pdev->name, adc); if (ret) { dev_err(&pdev->dev, "failed to request IRQ\n"); return ret; |
