| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Eugen Hristev | 6071 | 79.22% | 8 | 47.06% |
| Ludovic Desroches | 1564 | 20.41% | 5 | 29.41% |
| Dan Carpenter | 15 | 0.20% | 1 | 5.88% |
| Marek Vašut | 7 | 0.09% | 1 | 5.88% |
| Kefeng Wang | 4 | 0.05% | 1 | 5.88% |
| Thomas Gleixner | 2 | 0.03% | 1 | 5.88% |
| Total | 7663 | 17 |
// SPDX-License-Identifier: GPL-2.0-only /* * Atmel ADC driver for SAMA5D2 devices and compatible. * * Copyright (C) 2015 Atmel, * 2015 Ludovic Desroches <ludovic.desroches@atmel.com> */ #include <linux/bitops.h> #include <linux/clk.h> #include <linux/dma-mapping.h> #include <linux/dmaengine.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/module.h> #include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/sched.h> #include <linux/wait.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> #include <linux/iio/buffer.h> #include <linux/iio/trigger.h> #include <linux/iio/trigger_consumer.h> #include <linux/iio/triggered_buffer.h> #include <linux/pinctrl/consumer.h> #include <linux/regulator/consumer.h> /* Control Register */ #define AT91_SAMA5D2_CR 0x00 /* Software Reset */ #define AT91_SAMA5D2_CR_SWRST BIT(0) /* Start Conversion */ #define AT91_SAMA5D2_CR_START BIT(1) /* Touchscreen Calibration */ #define AT91_SAMA5D2_CR_TSCALIB BIT(2) /* Comparison Restart */ #define AT91_SAMA5D2_CR_CMPRST BIT(4) /* Mode Register */ #define AT91_SAMA5D2_MR 0x04 /* Trigger Selection */ #define AT91_SAMA5D2_MR_TRGSEL(v) ((v) << 1) /* ADTRG */ #define AT91_SAMA5D2_MR_TRGSEL_TRIG0 0 /* TIOA0 */ #define AT91_SAMA5D2_MR_TRGSEL_TRIG1 1 /* TIOA1 */ #define AT91_SAMA5D2_MR_TRGSEL_TRIG2 2 /* TIOA2 */ #define AT91_SAMA5D2_MR_TRGSEL_TRIG3 3 /* PWM event line 0 */ #define AT91_SAMA5D2_MR_TRGSEL_TRIG4 4 /* PWM event line 1 */ #define AT91_SAMA5D2_MR_TRGSEL_TRIG5 5 /* TIOA3 */ #define AT91_SAMA5D2_MR_TRGSEL_TRIG6 6 /* RTCOUT0 */ #define AT91_SAMA5D2_MR_TRGSEL_TRIG7 7 /* Sleep Mode */ #define AT91_SAMA5D2_MR_SLEEP BIT(5) /* Fast Wake Up */ #define AT91_SAMA5D2_MR_FWUP BIT(6) /* Prescaler Rate Selection */ #define AT91_SAMA5D2_MR_PRESCAL(v) ((v) << AT91_SAMA5D2_MR_PRESCAL_OFFSET) #define AT91_SAMA5D2_MR_PRESCAL_OFFSET 8 #define AT91_SAMA5D2_MR_PRESCAL_MAX 0xff #define AT91_SAMA5D2_MR_PRESCAL_MASK GENMASK(15, 8) /* Startup Time */ #define AT91_SAMA5D2_MR_STARTUP(v) ((v) << 16) #define AT91_SAMA5D2_MR_STARTUP_MASK GENMASK(19, 16) /* Analog Change */ #define AT91_SAMA5D2_MR_ANACH BIT(23) /* Tracking Time */ #define AT91_SAMA5D2_MR_TRACKTIM(v) ((v) << 24) #define AT91_SAMA5D2_MR_TRACKTIM_MAX 0xff /* Transfer Time */ #define AT91_SAMA5D2_MR_TRANSFER(v) ((v) << 28) #define AT91_SAMA5D2_MR_TRANSFER_MAX 0x3 /* Use Sequence Enable */ #define AT91_SAMA5D2_MR_USEQ BIT(31) /* Channel Sequence Register 1 */ #define AT91_SAMA5D2_SEQR1 0x08 /* Channel Sequence Register 2 */ #define AT91_SAMA5D2_SEQR2 0x0c /* Channel Enable Register */ #define AT91_SAMA5D2_CHER 0x10 /* Channel Disable Register */ #define AT91_SAMA5D2_CHDR 0x14 /* Channel Status Register */ #define AT91_SAMA5D2_CHSR 0x18 /* Last Converted Data Register */ #define AT91_SAMA5D2_LCDR 0x20 /* Interrupt Enable Register */ #define AT91_SAMA5D2_IER 0x24 /* Interrupt Enable Register - TS X measurement ready */ #define AT91_SAMA5D2_IER_XRDY BIT(20) /* Interrupt Enable Register - TS Y measurement ready */ #define AT91_SAMA5D2_IER_YRDY BIT(21) /* Interrupt Enable Register - TS pressure measurement ready */ #define AT91_SAMA5D2_IER_PRDY BIT(22) /* Interrupt Enable Register - general overrun error */ #define AT91_SAMA5D2_IER_GOVRE BIT(25) /* Interrupt Enable Register - Pen detect */ #define AT91_SAMA5D2_IER_PEN BIT(29) /* Interrupt Enable Register - No pen detect */ #define AT91_SAMA5D2_IER_NOPEN BIT(30) /* Interrupt Disable Register */ #define AT91_SAMA5D2_IDR 0x28 /* Interrupt Mask Register */ #define AT91_SAMA5D2_IMR 0x2c /* Interrupt Status Register */ #define AT91_SAMA5D2_ISR 0x30 /* Interrupt Status Register - Pen touching sense status */ #define AT91_SAMA5D2_ISR_PENS BIT(31) /* Last Channel Trigger Mode Register */ #define AT91_SAMA5D2_LCTMR 0x34 /* Last Channel Compare Window Register */ #define AT91_SAMA5D2_LCCWR 0x38 /* Overrun Status Register */ #define AT91_SAMA5D2_OVER 0x3c /* Extended Mode Register */ #define AT91_SAMA5D2_EMR 0x40 /* Extended Mode Register - Oversampling rate */ #define AT91_SAMA5D2_EMR_OSR(V) ((V) << 16) #define AT91_SAMA5D2_EMR_OSR_MASK GENMASK(17, 16) #define AT91_SAMA5D2_EMR_OSR_1SAMPLES 0 #define AT91_SAMA5D2_EMR_OSR_4SAMPLES 1 #define AT91_SAMA5D2_EMR_OSR_16SAMPLES 2 /* Extended Mode Register - Averaging on single trigger event */ #define AT91_SAMA5D2_EMR_ASTE(V) ((V) << 20) /* Compare Window Register */ #define AT91_SAMA5D2_CWR 0x44 /* Channel Gain Register */ #define AT91_SAMA5D2_CGR 0x48 /* Channel Offset Register */ #define AT91_SAMA5D2_COR 0x4c #define AT91_SAMA5D2_COR_DIFF_OFFSET 16 /* Channel Data Register 0 */ #define AT91_SAMA5D2_CDR0 0x50 /* Analog Control Register */ #define AT91_SAMA5D2_ACR 0x94 /* Analog Control Register - Pen detect sensitivity mask */ #define AT91_SAMA5D2_ACR_PENDETSENS_MASK GENMASK(1, 0) /* Touchscreen Mode Register */ #define AT91_SAMA5D2_TSMR 0xb0 /* Touchscreen Mode Register - No touch mode */ #define AT91_SAMA5D2_TSMR_TSMODE_NONE 0 /* Touchscreen Mode Register - 4 wire screen, no pressure measurement */ #define AT91_SAMA5D2_TSMR_TSMODE_4WIRE_NO_PRESS 1 /* Touchscreen Mode Register - 4 wire screen, pressure measurement */ #define AT91_SAMA5D2_TSMR_TSMODE_4WIRE_PRESS 2 /* Touchscreen Mode Register - 5 wire screen */ #define AT91_SAMA5D2_TSMR_TSMODE_5WIRE 3 /* Touchscreen Mode Register - Average samples mask */ #define AT91_SAMA5D2_TSMR_TSAV_MASK GENMASK(5, 4) /* Touchscreen Mode Register - Average samples */ #define AT91_SAMA5D2_TSMR_TSAV(x) ((x) << 4) /* Touchscreen Mode Register - Touch/trigger frequency ratio mask */ #define AT91_SAMA5D2_TSMR_TSFREQ_MASK GENMASK(11, 8) /* Touchscreen Mode Register - Touch/trigger frequency ratio */ #define AT91_SAMA5D2_TSMR_TSFREQ(x) ((x) << 8) /* Touchscreen Mode Register - Pen Debounce Time mask */ #define AT91_SAMA5D2_TSMR_PENDBC_MASK GENMASK(31, 28) /* Touchscreen Mode Register - Pen Debounce Time */ #define AT91_SAMA5D2_TSMR_PENDBC(x) ((x) << 28) /* Touchscreen Mode Register - No DMA for touch measurements */ #define AT91_SAMA5D2_TSMR_NOTSDMA BIT(22) /* Touchscreen Mode Register - Disable pen detection */ #define AT91_SAMA5D2_TSMR_PENDET_DIS (0 << 24) /* Touchscreen Mode Register - Enable pen detection */ #define AT91_SAMA5D2_TSMR_PENDET_ENA BIT(24) /* Touchscreen X Position Register */ #define AT91_SAMA5D2_XPOSR 0xb4 /* Touchscreen Y Position Register */ #define AT91_SAMA5D2_YPOSR 0xb8 /* Touchscreen Pressure Register */ #define AT91_SAMA5D2_PRESSR 0xbc /* Trigger Register */ #define AT91_SAMA5D2_TRGR 0xc0 /* Mask for TRGMOD field of TRGR register */ #define AT91_SAMA5D2_TRGR_TRGMOD_MASK GENMASK(2, 0) /* No trigger, only software trigger can start conversions */ #define AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER 0 /* Trigger Mode external trigger rising edge */ #define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE 1 /* Trigger Mode external trigger falling edge */ #define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL 2 /* Trigger Mode external trigger any edge */ #define AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY 3 /* Trigger Mode internal periodic */ #define AT91_SAMA5D2_TRGR_TRGMOD_PERIODIC 5 /* Trigger Mode - trigger period mask */ #define AT91_SAMA5D2_TRGR_TRGPER_MASK GENMASK(31, 16) /* Trigger Mode - trigger period */ #define AT91_SAMA5D2_TRGR_TRGPER(x) ((x) << 16) /* Correction Select Register */ #define AT91_SAMA5D2_COSR 0xd0 /* Correction Value Register */ #define AT91_SAMA5D2_CVR 0xd4 /* Channel Error Correction Register */ #define AT91_SAMA5D2_CECR 0xd8 /* Write Protection Mode Register */ #define AT91_SAMA5D2_WPMR 0xe4 /* Write Protection Status Register */ #define AT91_SAMA5D2_WPSR 0xe8 /* Version Register */ #define AT91_SAMA5D2_VERSION 0xfc #define AT91_SAMA5D2_HW_TRIG_CNT 3 #define AT91_SAMA5D2_SINGLE_CHAN_CNT 12 #define AT91_SAMA5D2_DIFF_CHAN_CNT 6 #define AT91_SAMA5D2_TIMESTAMP_CHAN_IDX (AT91_SAMA5D2_SINGLE_CHAN_CNT + \ AT91_SAMA5D2_DIFF_CHAN_CNT + 1) #define AT91_SAMA5D2_TOUCH_X_CHAN_IDX (AT91_SAMA5D2_SINGLE_CHAN_CNT + \ AT91_SAMA5D2_DIFF_CHAN_CNT * 2) #define AT91_SAMA5D2_TOUCH_Y_CHAN_IDX (AT91_SAMA5D2_TOUCH_X_CHAN_IDX + 1) #define AT91_SAMA5D2_TOUCH_P_CHAN_IDX (AT91_SAMA5D2_TOUCH_Y_CHAN_IDX + 1) #define AT91_SAMA5D2_MAX_CHAN_IDX AT91_SAMA5D2_TOUCH_P_CHAN_IDX #define AT91_SAMA5D2_TOUCH_SAMPLE_PERIOD_US 2000 /* 2ms */ #define AT91_SAMA5D2_TOUCH_PEN_DETECT_DEBOUNCE_US 200 #define AT91_SAMA5D2_XYZ_MASK GENMASK(11, 0) #define AT91_SAMA5D2_MAX_POS_BITS 12 /* * Maximum number of bytes to hold conversion from all channels * without the timestamp. */ #define AT91_BUFFER_MAX_CONVERSION_BYTES ((AT91_SAMA5D2_SINGLE_CHAN_CNT + \ AT91_SAMA5D2_DIFF_CHAN_CNT) * 2) /* This total must also include the timestamp */ #define AT91_BUFFER_MAX_BYTES (AT91_BUFFER_MAX_CONVERSION_BYTES + 8) #define AT91_BUFFER_MAX_HWORDS (AT91_BUFFER_MAX_BYTES / 2) #define AT91_HWFIFO_MAX_SIZE_STR "128" #define AT91_HWFIFO_MAX_SIZE 128 /* Possible values for oversampling ratio */ #define AT91_OSR_1SAMPLES 1 #define AT91_OSR_4SAMPLES 4 #define AT91_OSR_16SAMPLES 16 #define AT91_SAMA5D2_CHAN_SINGLE(num, addr) \ { \ .type = IIO_VOLTAGE, \ .channel = num, \ .address = addr, \ .scan_index = num, \ .scan_type = { \ .sign = 'u', \ .realbits = 14, \ .storagebits = 16, \ }, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ)|\ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ .datasheet_name = "CH"#num, \ .indexed = 1, \ } #define AT91_SAMA5D2_CHAN_DIFF(num, num2, addr) \ { \ .type = IIO_VOLTAGE, \ .differential = 1, \ .channel = num, \ .channel2 = num2, \ .address = addr, \ .scan_index = num + AT91_SAMA5D2_SINGLE_CHAN_CNT, \ .scan_type = { \ .sign = 's', \ .realbits = 14, \ .storagebits = 16, \ }, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ)|\ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ .datasheet_name = "CH"#num"-CH"#num2, \ .indexed = 1, \ } #define AT91_SAMA5D2_CHAN_TOUCH(num, name, mod) \ { \ .type = IIO_POSITIONRELATIVE, \ .modified = 1, \ .channel = num, \ .channel2 = mod, \ .scan_index = num, \ .scan_type = { \ .sign = 'u', \ .realbits = 12, \ .storagebits = 16, \ }, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ)|\ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ .datasheet_name = name, \ } #define AT91_SAMA5D2_CHAN_PRESSURE(num, name) \ { \ .type = IIO_PRESSURE, \ .channel = num, \ .scan_index = num, \ .scan_type = { \ .sign = 'u', \ .realbits = 12, \ .storagebits = 16, \ }, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ)|\ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \ .datasheet_name = name, \ } #define at91_adc_readl(st, reg) readl_relaxed(st->base + reg) #define at91_adc_writel(st, reg, val) writel_relaxed(val, st->base + reg) struct at91_adc_soc_info { unsigned startup_time; unsigned min_sample_rate; unsigned max_sample_rate; }; struct at91_adc_trigger { char *name; unsigned int trgmod_value; unsigned int edge_type; bool hw_trig; }; /** * at91_adc_dma - at91-sama5d2 dma information struct * @dma_chan: the dma channel acquired * @rx_buf: dma coherent allocated area * @rx_dma_buf: dma handler for the buffer * @phys_addr: physical address of the ADC base register * @buf_idx: index inside the dma buffer where reading was last done * @rx_buf_sz: size of buffer used by DMA operation * @watermark: number of conversions to copy before DMA triggers irq * @dma_ts: hold the start timestamp of dma operation */ struct at91_adc_dma { struct dma_chan *dma_chan; u8 *rx_buf; dma_addr_t rx_dma_buf; phys_addr_t phys_addr; int buf_idx; int rx_buf_sz; int watermark; s64 dma_ts; }; /** * at91_adc_touch - at91-sama5d2 touchscreen information struct * @sample_period_val: the value for periodic trigger interval * @touching: is the pen touching the screen or not * @x_pos: temporary placeholder for pressure computation * @channels_bitmask: bitmask with the touchscreen channels enabled * @workq: workqueue for buffer data pushing */ struct at91_adc_touch { u16 sample_period_val; bool touching; u16 x_pos; unsigned long channels_bitmask; struct work_struct workq; }; struct at91_adc_state { void __iomem *base; int irq; struct clk *per_clk; struct regulator *reg; struct regulator *vref; int vref_uv; unsigned int current_sample_rate; struct iio_trigger *trig; const struct at91_adc_trigger *selected_trig; const struct iio_chan_spec *chan; bool conversion_done; u32 conversion_value; unsigned int oversampling_ratio; struct at91_adc_soc_info soc_info; wait_queue_head_t wq_data_available; struct at91_adc_dma dma_st; struct at91_adc_touch touch_st; u16 buffer[AT91_BUFFER_MAX_HWORDS]; /* * lock to prevent concurrent 'single conversion' requests through * sysfs. */ struct mutex lock; }; static const struct at91_adc_trigger at91_adc_trigger_list[] = { { .name = "external_rising", .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_RISE, .edge_type = IRQ_TYPE_EDGE_RISING, .hw_trig = true, }, { .name = "external_falling", .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_FALL, .edge_type = IRQ_TYPE_EDGE_FALLING, .hw_trig = true, }, { .name = "external_any", .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_EXT_TRIG_ANY, .edge_type = IRQ_TYPE_EDGE_BOTH, .hw_trig = true, }, { .name = "software", .trgmod_value = AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER, .edge_type = IRQ_TYPE_NONE, .hw_trig = false, }, }; static const struct iio_chan_spec at91_adc_channels[] = { AT91_SAMA5D2_CHAN_SINGLE(0, 0x50), AT91_SAMA5D2_CHAN_SINGLE(1, 0x54), AT91_SAMA5D2_CHAN_SINGLE(2, 0x58), AT91_SAMA5D2_CHAN_SINGLE(3, 0x5c), AT91_SAMA5D2_CHAN_SINGLE(4, 0x60), AT91_SAMA5D2_CHAN_SINGLE(5, 0x64), AT91_SAMA5D2_CHAN_SINGLE(6, 0x68), AT91_SAMA5D2_CHAN_SINGLE(7, 0x6c), AT91_SAMA5D2_CHAN_SINGLE(8, 0x70), AT91_SAMA5D2_CHAN_SINGLE(9, 0x74), AT91_SAMA5D2_CHAN_SINGLE(10, 0x78), AT91_SAMA5D2_CHAN_SINGLE(11, 0x7c), AT91_SAMA5D2_CHAN_DIFF(0, 1, 0x50), AT91_SAMA5D2_CHAN_DIFF(2, 3, 0x58), AT91_SAMA5D2_CHAN_DIFF(4, 5, 0x60), AT91_SAMA5D2_CHAN_DIFF(6, 7, 0x68), AT91_SAMA5D2_CHAN_DIFF(8, 9, 0x70), AT91_SAMA5D2_CHAN_DIFF(10, 11, 0x78), IIO_CHAN_SOFT_TIMESTAMP(AT91_SAMA5D2_TIMESTAMP_CHAN_IDX), AT91_SAMA5D2_CHAN_TOUCH(AT91_SAMA5D2_TOUCH_X_CHAN_IDX, "x", IIO_MOD_X), AT91_SAMA5D2_CHAN_TOUCH(AT91_SAMA5D2_TOUCH_Y_CHAN_IDX, "y", IIO_MOD_Y), AT91_SAMA5D2_CHAN_PRESSURE(AT91_SAMA5D2_TOUCH_P_CHAN_IDX, "pressure"), }; static int at91_adc_chan_xlate(struct iio_dev *indio_dev, int chan) { int i; for (i = 0; i < indio_dev->num_channels; i++) { if (indio_dev->channels[i].scan_index == chan) return i; } return -EINVAL; } static inline struct iio_chan_spec const * at91_adc_chan_get(struct iio_dev *indio_dev, int chan) { int index = at91_adc_chan_xlate(indio_dev, chan); if (index < 0) return NULL; return indio_dev->channels + index; } static inline int at91_adc_of_xlate(struct iio_dev *indio_dev, const struct of_phandle_args *iiospec) { return at91_adc_chan_xlate(indio_dev, iiospec->args[0]); } static void at91_adc_config_emr(struct at91_adc_state *st) { /* configure the extended mode register */ unsigned int emr = at91_adc_readl(st, AT91_SAMA5D2_EMR); /* select oversampling per single trigger event */ emr |= AT91_SAMA5D2_EMR_ASTE(1); /* delete leftover content if it's the case */ emr &= ~AT91_SAMA5D2_EMR_OSR_MASK; /* select oversampling ratio from configuration */ switch (st->oversampling_ratio) { case AT91_OSR_1SAMPLES: emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_1SAMPLES) & AT91_SAMA5D2_EMR_OSR_MASK; break; case AT91_OSR_4SAMPLES: emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_4SAMPLES) & AT91_SAMA5D2_EMR_OSR_MASK; break; case AT91_OSR_16SAMPLES: emr |= AT91_SAMA5D2_EMR_OSR(AT91_SAMA5D2_EMR_OSR_16SAMPLES) & AT91_SAMA5D2_EMR_OSR_MASK; break; } at91_adc_writel(st, AT91_SAMA5D2_EMR, emr); } static int at91_adc_adjust_val_osr(struct at91_adc_state *st, int *val) { if (st->oversampling_ratio == AT91_OSR_1SAMPLES) { /* * in this case we only have 12 bits of real data, but channel * is registered as 14 bits, so shift left two bits */ *val <<= 2; } else if (st->oversampling_ratio == AT91_OSR_4SAMPLES) { /* * in this case we have 13 bits of real data, but channel * is registered as 14 bits, so left shift one bit */ *val <<= 1; } return IIO_VAL_INT; } static void at91_adc_adjust_val_osr_array(struct at91_adc_state *st, void *buf, int len) { int i = 0, val; u16 *buf_u16 = (u16 *) buf; /* * We are converting each two bytes (each sample). * First convert the byte based array to u16, and convert each sample * separately. * Each value is two bytes in an array of chars, so to not shift * more than we need, save the value separately. * len is in bytes, so divide by two to get number of samples. */ while (i < len / 2) { val = buf_u16[i]; at91_adc_adjust_val_osr(st, &val); buf_u16[i] = val; i++; } } static int at91_adc_configure_touch(struct at91_adc_state *st, bool state) { u32 clk_khz = st->current_sample_rate / 1000; int i = 0; u16 pendbc; u32 tsmr, acr; if (!state) { /* disabling touch IRQs and setting mode to no touch enabled */ at91_adc_writel(st, AT91_SAMA5D2_IDR, AT91_SAMA5D2_IER_PEN | AT91_SAMA5D2_IER_NOPEN); at91_adc_writel(st, AT91_SAMA5D2_TSMR, 0); return 0; } /* * debounce time is in microseconds, we need it in milliseconds to * multiply with kilohertz, so, divide by 1000, but after the multiply. * round up to make sure pendbc is at least 1 */ pendbc = round_up(AT91_SAMA5D2_TOUCH_PEN_DETECT_DEBOUNCE_US * clk_khz / 1000, 1); /* get the required exponent */ while (pendbc >> i++) ; pendbc = i; tsmr = AT91_SAMA5D2_TSMR_TSMODE_4WIRE_PRESS; tsmr |= AT91_SAMA5D2_TSMR_TSAV(2) & AT91_SAMA5D2_TSMR_TSAV_MASK; tsmr |= AT91_SAMA5D2_TSMR_PENDBC(pendbc) & AT91_SAMA5D2_TSMR_PENDBC_MASK; tsmr |= AT91_SAMA5D2_TSMR_NOTSDMA; tsmr |= AT91_SAMA5D2_TSMR_PENDET_ENA; tsmr |= AT91_SAMA5D2_TSMR_TSFREQ(2) & AT91_SAMA5D2_TSMR_TSFREQ_MASK; at91_adc_writel(st, AT91_SAMA5D2_TSMR, tsmr); acr = at91_adc_readl(st, AT91_SAMA5D2_ACR); acr &= ~AT91_SAMA5D2_ACR_PENDETSENS_MASK; acr |= 0x02 & AT91_SAMA5D2_ACR_PENDETSENS_MASK; at91_adc_writel(st, AT91_SAMA5D2_ACR, acr); /* Sample Period Time = (TRGPER + 1) / ADCClock */ st->touch_st.sample_period_val = round_up((AT91_SAMA5D2_TOUCH_SAMPLE_PERIOD_US * clk_khz / 1000) - 1, 1); /* enable pen detect IRQ */ at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_PEN); return 0; } static u16 at91_adc_touch_pos(struct at91_adc_state *st, int reg) { u32 val; u32 scale, result, pos; /* * to obtain the actual position we must divide by scale * and multiply with max, where * max = 2^AT91_SAMA5D2_MAX_POS_BITS - 1 */ /* first half of register is the x or y, second half is the scale */ val = at91_adc_readl(st, reg); if (!val) dev_dbg(&iio_priv_to_dev(st)->dev, "pos is 0\n"); pos = val & AT91_SAMA5D2_XYZ_MASK; result = (pos << AT91_SAMA5D2_MAX_POS_BITS) - pos; scale = (val >> 16) & AT91_SAMA5D2_XYZ_MASK; if (scale == 0) { dev_err(&iio_priv_to_dev(st)->dev, "scale is 0\n"); return 0; } result /= scale; return result; } static u16 at91_adc_touch_x_pos(struct at91_adc_state *st) { st->touch_st.x_pos = at91_adc_touch_pos(st, AT91_SAMA5D2_XPOSR); return st->touch_st.x_pos; } static u16 at91_adc_touch_y_pos(struct at91_adc_state *st) { return at91_adc_touch_pos(st, AT91_SAMA5D2_YPOSR); } static u16 at91_adc_touch_pressure(struct at91_adc_state *st) { u32 val; u32 z1, z2; u32 pres; u32 rxp = 1; u32 factor = 1000; /* calculate the pressure */ val = at91_adc_readl(st, AT91_SAMA5D2_PRESSR); z1 = val & AT91_SAMA5D2_XYZ_MASK; z2 = (val >> 16) & AT91_SAMA5D2_XYZ_MASK; if (z1 != 0) pres = rxp * (st->touch_st.x_pos * factor / 1024) * (z2 * factor / z1 - factor) / factor; else pres = 0xFFFF; /* no pen contact */ /* * The pressure from device grows down, minimum is 0xFFFF, maximum 0x0. * We compute it this way, but let's return it in the expected way, * growing from 0 to 0xFFFF. */ return 0xFFFF - pres; } static int at91_adc_read_position(struct at91_adc_state *st, int chan, u16 *val) { *val = 0; if (!st->touch_st.touching) return -ENODATA; if (chan == AT91_SAMA5D2_TOUCH_X_CHAN_IDX) *val = at91_adc_touch_x_pos(st); else if (chan == AT91_SAMA5D2_TOUCH_Y_CHAN_IDX) *val = at91_adc_touch_y_pos(st); else return -ENODATA; return IIO_VAL_INT; } static int at91_adc_read_pressure(struct at91_adc_state *st, int chan, u16 *val) { *val = 0; if (!st->touch_st.touching) return -ENODATA; if (chan == AT91_SAMA5D2_TOUCH_P_CHAN_IDX) *val = at91_adc_touch_pressure(st); else return -ENODATA; return IIO_VAL_INT; } static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state) { struct iio_dev *indio = iio_trigger_get_drvdata(trig); struct at91_adc_state *st = iio_priv(indio); u32 status = at91_adc_readl(st, AT91_SAMA5D2_TRGR); u8 bit; /* clear TRGMOD */ status &= ~AT91_SAMA5D2_TRGR_TRGMOD_MASK; if (state) status |= st->selected_trig->trgmod_value; /* set/unset hw trigger */ at91_adc_writel(st, AT91_SAMA5D2_TRGR, status); for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) { struct iio_chan_spec const *chan = at91_adc_chan_get(indio, bit); if (!chan) continue; /* these channel types cannot be handled by this trigger */ if (chan->type == IIO_POSITIONRELATIVE || chan->type == IIO_PRESSURE) continue; if (state) { at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel)); /* enable irq only if not using DMA */ if (!st->dma_st.dma_chan) { at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel)); } } else { /* disable irq only if not using DMA */ if (!st->dma_st.dma_chan) { at91_adc_writel(st, AT91_SAMA5D2_IDR, BIT(chan->channel)); } at91_adc_writel(st, AT91_SAMA5D2_CHDR, BIT(chan->channel)); } } return 0; } static int at91_adc_reenable_trigger(struct iio_trigger *trig) { struct iio_dev *indio = iio_trigger_get_drvdata(trig); struct at91_adc_state *st = iio_priv(indio); /* if we are using DMA, we must not reenable irq after each trigger */ if (st->dma_st.dma_chan) return 0; enable_irq(st->irq); /* Needed to ACK the DRDY interruption */ at91_adc_readl(st, AT91_SAMA5D2_LCDR); return 0; } static const struct iio_trigger_ops at91_adc_trigger_ops = { .set_trigger_state = &at91_adc_configure_trigger, .try_reenable = &at91_adc_reenable_trigger, .validate_device = iio_trigger_validate_own_device, }; static int at91_adc_dma_size_done(struct at91_adc_state *st) { struct dma_tx_state state; enum dma_status status; int i, size; status = dmaengine_tx_status(st->dma_st.dma_chan, st->dma_st.dma_chan->cookie, &state); if (status != DMA_IN_PROGRESS) return 0; /* Transferred length is size in bytes from end of buffer */ i = st->dma_st.rx_buf_sz - state.residue; /* Return available bytes */ if (i >= st->dma_st.buf_idx) size = i - st->dma_st.buf_idx; else size = st->dma_st.rx_buf_sz + i - st->dma_st.buf_idx; return size; } static void at91_dma_buffer_done(void *data) { struct iio_dev *indio_dev = data; iio_trigger_poll_chained(indio_dev->trig); } static int at91_adc_dma_start(struct iio_dev *indio_dev) { struct at91_adc_state *st = iio_priv(indio_dev); struct dma_async_tx_descriptor *desc; dma_cookie_t cookie; int ret; u8 bit; if (!st->dma_st.dma_chan) return 0; /* we start a new DMA, so set buffer index to start */ st->dma_st.buf_idx = 0; /* * compute buffer size w.r.t. watermark and enabled channels. * scan_bytes is aligned so we need an exact size for DMA */ st->dma_st.rx_buf_sz = 0; for_each_set_bit(bit, indio_dev->active_scan_mask, indio_dev->num_channels) { struct iio_chan_spec const *chan = at91_adc_chan_get(indio_dev, bit); if (!chan) continue; st->dma_st.rx_buf_sz += chan->scan_type.storagebits / 8; } st->dma_st.rx_buf_sz *= st->dma_st.watermark; /* Prepare a DMA cyclic transaction */ desc = dmaengine_prep_dma_cyclic(st->dma_st.dma_chan, st->dma_st.rx_dma_buf, st->dma_st.rx_buf_sz, st->dma_st.rx_buf_sz / 2, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT); if (!desc) { dev_err(&indio_dev->dev, "cannot prepare DMA cyclic\n"); return -EBUSY; } desc->callback = at91_dma_buffer_done; desc->callback_param = indio_dev; cookie = dmaengine_submit(desc); ret = dma_submit_error(cookie); if (ret) { dev_err(&indio_dev->dev, "cannot submit DMA cyclic\n"); dmaengine_terminate_async(st->dma_st.dma_chan); return ret; } /* enable general overrun error signaling */ at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_GOVRE); /* Issue pending DMA requests */ dma_async_issue_pending(st->dma_st.dma_chan); /* consider current time as DMA start time for timestamps */ st->dma_st.dma_ts = iio_get_time_ns(indio_dev); dev_dbg(&indio_dev->dev, "DMA cyclic started\n"); return 0; } static int at91_adc_buffer_postenable(struct iio_dev *indio_dev) { int ret; struct at91_adc_state *st = iio_priv(indio_dev); /* check if we are enabling triggered buffer or the touchscreen */ if (bitmap_subset(indio_dev->active_scan_mask, &st->touch_st.channels_bitmask, AT91_SAMA5D2_MAX_CHAN_IDX + 1)) { /* touchscreen enabling */ return at91_adc_configure_touch(st, true); } /* if we are not in triggered mode, we cannot enable the buffer. */ if (!(indio_dev->currentmode & INDIO_ALL_TRIGGERED_MODES)) return -EINVAL; /* we continue with the triggered buffer */ ret = at91_adc_dma_start(indio_dev); if (ret) { dev_err(&indio_dev->dev, "buffer postenable failed\n"); return ret; } return iio_triggered_buffer_postenable(indio_dev); } static int at91_adc_buffer_predisable(struct iio_dev *indio_dev) { struct at91_adc_state *st = iio_priv(indio_dev); int ret; u8 bit; /* check if we are disabling triggered buffer or the touchscreen */ if (bitmap_subset(indio_dev->active_scan_mask, &st->touch_st.channels_bitmask, AT91_SAMA5D2_MAX_CHAN_IDX + 1)) { /* touchscreen disable */ return at91_adc_configure_touch(st, false); } /* if we are not in triggered mode, nothing to do here */ if (!(indio_dev->currentmode & INDIO_ALL_TRIGGERED_MODES)) return -EINVAL; /* continue with the triggered buffer */ ret = iio_triggered_buffer_predisable(indio_dev); if (ret < 0) dev_err(&indio_dev->dev, "buffer predisable failed\n"); if (!st->dma_st.dma_chan) return ret; /* if we are using DMA we must clear registers and end DMA */ dmaengine_terminate_sync(st->dma_st.dma_chan); /* * For each enabled channel we must read the last converted value * to clear EOC status and not get a possible interrupt later. * This value is being read by DMA from LCDR anyway */ for_each_set_bit(bit, indio_dev->active_scan_mask, indio_dev->num_channels) { struct iio_chan_spec const *chan = at91_adc_chan_get(indio_dev, bit); if (!chan) continue; /* these channel types are virtual, no need to do anything */ if (chan->type == IIO_POSITIONRELATIVE || chan->type == IIO_PRESSURE) continue; if (st->dma_st.dma_chan) at91_adc_readl(st, chan->address); } /* read overflow register to clear possible overflow status */ at91_adc_readl(st, AT91_SAMA5D2_OVER); return ret; } static const struct iio_buffer_setup_ops at91_buffer_setup_ops = { .postenable = &at91_adc_buffer_postenable, .predisable = &at91_adc_buffer_predisable, }; static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *indio, char *trigger_name) { struct iio_trigger *trig; int ret; trig = devm_iio_trigger_alloc(&indio->dev, "%s-dev%d-%s", indio->name, indio->id, trigger_name); if (!trig) return NULL; trig->dev.parent = indio->dev.parent; iio_trigger_set_drvdata(trig, indio); trig->ops = &at91_adc_trigger_ops; ret = devm_iio_trigger_register(&indio->dev, trig); if (ret) return ERR_PTR(ret); return trig; } static int at91_adc_trigger_init(struct iio_dev *indio) { struct at91_adc_state *st = iio_priv(indio); st->trig = at91_adc_allocate_trigger(indio, st->selected_trig->name); if (IS_ERR(st->trig)) { dev_err(&indio->dev, "could not allocate trigger\n"); return PTR_ERR(st->trig); } return 0; } static void at91_adc_trigger_handler_nodma(struct iio_dev *indio_dev, struct iio_poll_func *pf) { struct at91_adc_state *st = iio_priv(indio_dev); int i = 0; int val; u8 bit; for_each_set_bit(bit, indio_dev->active_scan_mask, indio_dev->num_channels) { struct iio_chan_spec const *chan = at91_adc_chan_get(indio_dev, bit); if (!chan) continue; /* * Our external trigger only supports the voltage channels. * In case someone requested a different type of channel * just put zeroes to buffer. * This should not happen because we check the scan mode * and scan mask when we enable the buffer, and we don't allow * the buffer to start with a mixed mask (voltage and something * else). * Thus, emit a warning. */ if (chan->type == IIO_VOLTAGE) { val = at91_adc_readl(st, chan->address); at91_adc_adjust_val_osr(st, &val); st->buffer[i] = val; } else { st->buffer[i] = 0; WARN(true, "This trigger cannot handle this type of channel"); } i++; } iio_push_to_buffers_with_timestamp(indio_dev, st->buffer, pf->timestamp); } static void at91_adc_trigger_handler_dma(struct iio_dev *indio_dev) { struct at91_adc_state *st = iio_priv(indio_dev); int transferred_len = at91_adc_dma_size_done(st); s64 ns = iio_get_time_ns(indio_dev); s64 interval; int sample_index = 0, sample_count, sample_size; u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR); /* if we reached this point, we cannot sample faster */ if (status & AT91_SAMA5D2_IER_GOVRE) pr_info_ratelimited("%s: conversion overrun detected\n", indio_dev->name); sample_size = div_s64(st->dma_st.rx_buf_sz, st->dma_st.watermark); sample_count = div_s64(transferred_len, sample_size); /* * interval between samples is total time since last transfer handling * divided by the number of samples (total size divided by sample size) */ interval = div_s64((ns - st->dma_st.dma_ts), sample_count); while (transferred_len >= sample_size) { /* * for all the values in the current sample, * adjust the values inside the buffer for oversampling */ at91_adc_adjust_val_osr_array(st, &st->dma_st.rx_buf[st->dma_st.buf_idx], sample_size); iio_push_to_buffers_with_timestamp(indio_dev, (st->dma_st.rx_buf + st->dma_st.buf_idx), (st->dma_st.dma_ts + interval * sample_index)); /* adjust remaining length */ transferred_len -= sample_size; /* adjust buffer index */ st->dma_st.buf_idx += sample_size; /* in case of reaching end of buffer, reset index */ if (st->dma_st.buf_idx >= st->dma_st.rx_buf_sz) st->dma_st.buf_idx = 0; sample_index++; } /* adjust saved time for next transfer handling */ st->dma_st.dma_ts = iio_get_time_ns(indio_dev); } static irqreturn_t at91_adc_trigger_handler(int irq, void *p) { struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct at91_adc_state *st = iio_priv(indio_dev); if (st->dma_st.dma_chan) at91_adc_trigger_handler_dma(indio_dev); else at91_adc_trigger_handler_nodma(indio_dev, pf); iio_trigger_notify_done(indio_dev->trig); return IRQ_HANDLED; } static int at91_adc_buffer_init(struct iio_dev *indio) { struct at91_adc_state *st = iio_priv(indio); if (st->selected_trig->hw_trig) { return devm_iio_triggered_buffer_setup(&indio->dev, indio, &iio_pollfunc_store_time, &at91_adc_trigger_handler, &at91_buffer_setup_ops); } /* * we need to prepare the buffer ops in case we will get * another buffer attached (like a callback buffer for the touchscreen) */ indio->setup_ops = &at91_buffer_setup_ops; return 0; } static unsigned at91_adc_startup_time(unsigned startup_time_min, unsigned adc_clk_khz) { static const unsigned int startup_lookup[] = { 0, 8, 16, 24, 64, 80, 96, 112, 512, 576, 640, 704, 768, 832, 896, 960 }; unsigned ticks_min, i; /* * Since the adc frequency is checked before, there is no reason * to not meet the startup time constraint. */ ticks_min = startup_time_min * adc_clk_khz / 1000; for (i = 0; i < ARRAY_SIZE(startup_lookup); i++) if (startup_lookup[i] > ticks_min) break; return i; } static void at91_adc_setup_samp_freq(struct at91_adc_state *st, unsigned freq) { struct iio_dev *indio_dev = iio_priv_to_dev(st); unsigned f_per, prescal, startup, mr; f_per = clk_get_rate(st->per_clk); prescal = (f_per / (2 * freq)) - 1; startup = at91_adc_startup_time(st->soc_info.startup_time, freq / 1000); mr = at91_adc_readl(st, AT91_SAMA5D2_MR); mr &= ~(AT91_SAMA5D2_MR_STARTUP_MASK | AT91_SAMA5D2_MR_PRESCAL_MASK); mr |= AT91_SAMA5D2_MR_STARTUP(startup); mr |= AT91_SAMA5D2_MR_PRESCAL(prescal); at91_adc_writel(st, AT91_SAMA5D2_MR, mr); dev_dbg(&indio_dev->dev, "freq: %u, startup: %u, prescal: %u\n", freq, startup, prescal); st->current_sample_rate = freq; } static inline unsigned at91_adc_get_sample_freq(struct at91_adc_state *st) { return st->current_sample_rate; } static void at91_adc_touch_data_handler(struct iio_dev *indio_dev) { struct at91_adc_state *st = iio_priv(indio_dev); u8 bit; u16 val; int i = 0; for_each_set_bit(bit, indio_dev->active_scan_mask, AT91_SAMA5D2_MAX_CHAN_IDX + 1) { struct iio_chan_spec const *chan = at91_adc_chan_get(indio_dev, bit); if (chan->type == IIO_POSITIONRELATIVE) at91_adc_read_position(st, chan->channel, &val); else if (chan->type == IIO_PRESSURE) at91_adc_read_pressure(st, chan->channel, &val); else continue; st->buffer[i] = val; i++; } /* * Schedule work to push to buffers. * This is intended to push to the callback buffer that another driver * registered. We are still in a handler from our IRQ. If we push * directly, it means the other driver has it's callback called * from our IRQ context. Which is something we better avoid. * Let's schedule it after our IRQ is completed. */ schedule_work(&st->touch_st.workq); } static void at91_adc_pen_detect_interrupt(struct at91_adc_state *st) { at91_adc_writel(st, AT91_SAMA5D2_IDR, AT91_SAMA5D2_IER_PEN); at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_NOPEN | AT91_SAMA5D2_IER_XRDY | AT91_SAMA5D2_IER_YRDY | AT91_SAMA5D2_IER_PRDY); at91_adc_writel(st, AT91_SAMA5D2_TRGR, AT91_SAMA5D2_TRGR_TRGMOD_PERIODIC | AT91_SAMA5D2_TRGR_TRGPER(st->touch_st.sample_period_val)); st->touch_st.touching = true; } static void at91_adc_no_pen_detect_interrupt(struct at91_adc_state *st) { struct iio_dev *indio_dev = iio_priv_to_dev(st); at91_adc_writel(st, AT91_SAMA5D2_TRGR, AT91_SAMA5D2_TRGR_TRGMOD_NO_TRIGGER); at91_adc_writel(st, AT91_SAMA5D2_IDR, AT91_SAMA5D2_IER_NOPEN | AT91_SAMA5D2_IER_XRDY | AT91_SAMA5D2_IER_YRDY | AT91_SAMA5D2_IER_PRDY); st->touch_st.touching = false; at91_adc_touch_data_handler(indio_dev); at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_PEN); } static void at91_adc_workq_handler(struct work_struct *workq) { struct at91_adc_touch *touch_st = container_of(workq, struct at91_adc_touch, workq); struct at91_adc_state *st = container_of(touch_st, struct at91_adc_state, touch_st); struct iio_dev *indio_dev = iio_priv_to_dev(st); iio_push_to_buffers(indio_dev, st->buffer); } static irqreturn_t at91_adc_interrupt(int irq, void *private) { struct iio_dev *indio = private; struct at91_adc_state *st = iio_priv(indio); u32 status = at91_adc_readl(st, AT91_SAMA5D2_ISR); u32 imr = at91_adc_readl(st, AT91_SAMA5D2_IMR); u32 rdy_mask = AT91_SAMA5D2_IER_XRDY | AT91_SAMA5D2_IER_YRDY | AT91_SAMA5D2_IER_PRDY; if (!(status & imr)) return IRQ_NONE; if (status & AT91_SAMA5D2_IER_PEN) { /* pen detected IRQ */ at91_adc_pen_detect_interrupt(st); } else if ((status & AT91_SAMA5D2_IER_NOPEN)) { /* nopen detected IRQ */ at91_adc_no_pen_detect_interrupt(st); } else if ((status & AT91_SAMA5D2_ISR_PENS) && ((status & rdy_mask) == rdy_mask)) { /* periodic trigger IRQ - during pen sense */ at91_adc_touch_data_handler(indio); } else if (status & AT91_SAMA5D2_ISR_PENS) { /* * touching, but the measurements are not ready yet. * read and ignore. */ status = at91_adc_readl(st, AT91_SAMA5D2_XPOSR); status = at91_adc_readl(st, AT91_SAMA5D2_YPOSR); status = at91_adc_readl(st, AT91_SAMA5D2_PRESSR); } else if (iio_buffer_enabled(indio) && !st->dma_st.dma_chan) { /* triggered buffer without DMA */ disable_irq_nosync(irq); iio_trigger_poll(indio->trig); } else if (iio_buffer_enabled(indio) && st->dma_st.dma_chan) { /* triggered buffer with DMA - should not happen */ disable_irq_nosync(irq); WARN(true, "Unexpected irq occurred\n"); } else if (!iio_buffer_enabled(indio)) { /* software requested conversion */ st->conversion_value = at91_adc_readl(st, st->chan->address); st->conversion_done = true; wake_up_interruptible(&st->wq_data_available); } return IRQ_HANDLED; } static int at91_adc_read_info_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val) { struct at91_adc_state *st = iio_priv(indio_dev); u32 cor = 0; u16 tmp_val; int ret; /* * Keep in mind that we cannot use software trigger or touchscreen * if external trigger is enabled */ if (chan->type == IIO_POSITIONRELATIVE) { ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; mutex_lock(&st->lock); ret = at91_adc_read_position(st, chan->channel, &tmp_val); *val = tmp_val; mutex_unlock(&st->lock); iio_device_release_direct_mode(indio_dev); return at91_adc_adjust_val_osr(st, val); } if (chan->type == IIO_PRESSURE) { ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; mutex_lock(&st->lock); ret = at91_adc_read_pressure(st, chan->channel, &tmp_val); *val = tmp_val; mutex_unlock(&st->lock); iio_device_release_direct_mode(indio_dev); return at91_adc_adjust_val_osr(st, val); } /* in this case we have a voltage channel */ ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; mutex_lock(&st->lock); st->chan = chan; if (chan->differential) cor = (BIT(chan->channel) | BIT(chan->channel2)) << AT91_SAMA5D2_COR_DIFF_OFFSET; at91_adc_writel(st, AT91_SAMA5D2_COR, cor); at91_adc_writel(st, AT91_SAMA5D2_CHER, BIT(chan->channel)); at91_adc_writel(st, AT91_SAMA5D2_IER, BIT(chan->channel)); at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_START); ret = wait_event_interruptible_timeout(st->wq_data_available, st->conversion_done, msecs_to_jiffies(1000)); if (ret == 0) ret = -ETIMEDOUT; if (ret > 0) { *val = st->conversion_value; ret = at91_adc_adjust_val_osr(st, val); if (chan->scan_type.sign == 's') *val = sign_extend32(*val, 11); st->conversion_done = false; } at91_adc_writel(st, AT91_SAMA5D2_IDR, BIT(chan->channel)); at91_adc_writel(st, AT91_SAMA5D2_CHDR, BIT(chan->channel)); /* Needed to ACK the DRDY interruption */ at91_adc_readl(st, AT91_SAMA5D2_LCDR); mutex_unlock(&st->lock); iio_device_release_direct_mode(indio_dev); return ret; } static int at91_adc_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct at91_adc_state *st = iio_priv(indio_dev); switch (mask) { case IIO_CHAN_INFO_RAW: return at91_adc_read_info_raw(indio_dev, chan, val); case IIO_CHAN_INFO_SCALE: *val = st->vref_uv / 1000; if (chan->differential) *val *= 2; *val2 = chan->scan_type.realbits; return IIO_VAL_FRACTIONAL_LOG2; case IIO_CHAN_INFO_SAMP_FREQ: *val = at91_adc_get_sample_freq(st); return IIO_VAL_INT; case IIO_CHAN_INFO_OVERSAMPLING_RATIO: *val = st->oversampling_ratio; return IIO_VAL_INT; default: return -EINVAL; } } static int at91_adc_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, int val2, long mask) { struct at91_adc_state *st = iio_priv(indio_dev); switch (mask) { case IIO_CHAN_INFO_OVERSAMPLING_RATIO: if ((val != AT91_OSR_1SAMPLES) && (val != AT91_OSR_4SAMPLES) && (val != AT91_OSR_16SAMPLES)) return -EINVAL; /* if no change, optimize out */ if (val == st->oversampling_ratio) return 0; st->oversampling_ratio = val; /* update ratio */ at91_adc_config_emr(st); return 0; case IIO_CHAN_INFO_SAMP_FREQ: if (val < st->soc_info.min_sample_rate || val > st->soc_info.max_sample_rate) return -EINVAL; at91_adc_setup_samp_freq(st, val); return 0; default: return -EINVAL; }; } static void at91_adc_dma_init(struct platform_device *pdev) { struct iio_dev *indio_dev = platform_get_drvdata(pdev); struct at91_adc_state *st = iio_priv(indio_dev); struct dma_slave_config config = {0}; /* * We make the buffer double the size of the fifo, * such that DMA uses one half of the buffer (full fifo size) * and the software uses the other half to read/write. */ unsigned int pages = DIV_ROUND_UP(AT91_HWFIFO_MAX_SIZE * AT91_BUFFER_MAX_CONVERSION_BYTES * 2, PAGE_SIZE); if (st->dma_st.dma_chan) return; st->dma_st.dma_chan = dma_request_slave_channel(&pdev->dev, "rx"); if (!st->dma_st.dma_chan) { dev_info(&pdev->dev, "can't get DMA channel\n"); goto dma_exit; } st->dma_st.rx_buf = dma_alloc_coherent(st->dma_st.dma_chan->device->dev, pages * PAGE_SIZE, &st->dma_st.rx_dma_buf, GFP_KERNEL); if (!st->dma_st.rx_buf) { dev_info(&pdev->dev, "can't allocate coherent DMA area\n"); goto dma_chan_disable; } /* Configure DMA channel to read data register */ config.direction = DMA_DEV_TO_MEM; config.src_addr = (phys_addr_t)(st->dma_st.phys_addr + AT91_SAMA5D2_LCDR); config.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; config.src_maxburst = 1; config.dst_maxburst = 1; if (dmaengine_slave_config(st->dma_st.dma_chan, &config)) { dev_info(&pdev->dev, "can't configure DMA slave\n"); goto dma_free_area; } dev_info(&pdev->dev, "using %s for rx DMA transfers\n", dma_chan_name(st->dma_st.dma_chan)); return; dma_free_area: dma_free_coherent(st->dma_st.dma_chan->device->dev, pages * PAGE_SIZE, st->dma_st.rx_buf, st->dma_st.rx_dma_buf); dma_chan_disable: dma_release_channel(st->dma_st.dma_chan); st->dma_st.dma_chan = 0; dma_exit: dev_info(&pdev->dev, "continuing without DMA support\n"); } static void at91_adc_dma_disable(struct platform_device *pdev) { struct iio_dev *indio_dev = platform_get_drvdata(pdev); struct at91_adc_state *st = iio_priv(indio_dev); unsigned int pages = DIV_ROUND_UP(AT91_HWFIFO_MAX_SIZE * AT91_BUFFER_MAX_CONVERSION_BYTES * 2, PAGE_SIZE); /* if we are not using DMA, just return */ if (!st->dma_st.dma_chan) return; /* wait for all transactions to be terminated first*/ dmaengine_terminate_sync(st->dma_st.dma_chan); dma_free_coherent(st->dma_st.dma_chan->device->dev, pages * PAGE_SIZE, st->dma_st.rx_buf, st->dma_st.rx_dma_buf); dma_release_channel(st->dma_st.dma_chan); st->dma_st.dma_chan = 0; dev_info(&pdev->dev, "continuing without DMA support\n"); } static int at91_adc_set_watermark(struct iio_dev *indio_dev, unsigned int val) { struct at91_adc_state *st = iio_priv(indio_dev); if (val > AT91_HWFIFO_MAX_SIZE) return -EINVAL; if (!st->selected_trig->hw_trig) { dev_dbg(&indio_dev->dev, "we need hw trigger for DMA\n"); return 0; } dev_dbg(&indio_dev->dev, "new watermark is %u\n", val); st->dma_st.watermark = val; /* * The logic here is: if we have watermark 1, it means we do * each conversion with it's own IRQ, thus we don't need DMA. * If the watermark is higher, we do DMA to do all the transfers in bulk */ if (val == 1) at91_adc_dma_disable(to_platform_device(&indio_dev->dev)); else if (val > 1) at91_adc_dma_init(to_platform_device(&indio_dev->dev)); return 0; } static int at91_adc_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask) { struct at91_adc_state *st = iio_priv(indio_dev); if (bitmap_subset(scan_mask, &st->touch_st.channels_bitmask, AT91_SAMA5D2_MAX_CHAN_IDX + 1)) return 0; /* * if the new bitmap is a combination of touchscreen and regular * channels, then we are not fine */ if (bitmap_intersects(&st->touch_st.channels_bitmask, scan_mask, AT91_SAMA5D2_MAX_CHAN_IDX + 1)) return -EINVAL; return 0; } static void at91_adc_hw_init(struct at91_adc_state *st) { at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_SWRST); at91_adc_writel(st, AT91_SAMA5D2_IDR, 0xffffffff); /* * Transfer field must be set to 2 according to the datasheet and * allows different analog settings for each channel. */ at91_adc_writel(st, AT91_SAMA5D2_MR, AT91_SAMA5D2_MR_TRANSFER(2) | AT91_SAMA5D2_MR_ANACH); at91_adc_setup_samp_freq(st, st->soc_info.min_sample_rate); /* configure extended mode register */ at91_adc_config_emr(st); } static ssize_t at91_adc_get_fifo_state(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct at91_adc_state *st = iio_priv(indio_dev); return scnprintf(buf, PAGE_SIZE, "%d\n", !!st->dma_st.dma_chan); } static ssize_t at91_adc_get_watermark(struct device *dev, struct device_attribute *attr, char *buf) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct at91_adc_state *st = iio_priv(indio_dev); return scnprintf(buf, PAGE_SIZE, "%d\n", st->dma_st.watermark); } static IIO_DEVICE_ATTR(hwfifo_enabled, 0444, at91_adc_get_fifo_state, NULL, 0); static IIO_DEVICE_ATTR(hwfifo_watermark, 0444, at91_adc_get_watermark, NULL, 0); static IIO_CONST_ATTR(hwfifo_watermark_min, "2"); static IIO_CONST_ATTR(hwfifo_watermark_max, AT91_HWFIFO_MAX_SIZE_STR); static IIO_CONST_ATTR(oversampling_ratio_available, __stringify(AT91_OSR_1SAMPLES) " " __stringify(AT91_OSR_4SAMPLES) " " __stringify(AT91_OSR_16SAMPLES)); static struct attribute *at91_adc_attributes[] = { &iio_const_attr_oversampling_ratio_available.dev_attr.attr, NULL, }; static const struct attribute_group at91_adc_attribute_group = { .attrs = at91_adc_attributes, }; static const struct attribute *at91_adc_fifo_attributes[] = { &iio_const_attr_hwfifo_watermark_min.dev_attr.attr, &iio_const_attr_hwfifo_watermark_max.dev_attr.attr, &iio_dev_attr_hwfifo_watermark.dev_attr.attr, &iio_dev_attr_hwfifo_enabled.dev_attr.attr, NULL, }; static const struct iio_info at91_adc_info = { .attrs = &at91_adc_attribute_group, .read_raw = &at91_adc_read_raw, .write_raw = &at91_adc_write_raw, .update_scan_mode = &at91_adc_update_scan_mode, .of_xlate = &at91_adc_of_xlate, .hwfifo_set_watermark = &at91_adc_set_watermark, }; static int at91_adc_probe(struct platform_device *pdev) { struct iio_dev *indio_dev; struct at91_adc_state *st; struct resource *res; int ret, i; u32 edge_type = IRQ_TYPE_NONE; indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*st)); if (!indio_dev) return -ENOMEM; indio_dev->dev.parent = &pdev->dev; indio_dev->name = dev_name(&pdev->dev); indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE; indio_dev->info = &at91_adc_info; indio_dev->channels = at91_adc_channels; indio_dev->num_channels = ARRAY_SIZE(at91_adc_channels); st = iio_priv(indio_dev); bitmap_set(&st->touch_st.channels_bitmask, AT91_SAMA5D2_TOUCH_X_CHAN_IDX, 1); bitmap_set(&st->touch_st.channels_bitmask, AT91_SAMA5D2_TOUCH_Y_CHAN_IDX, 1); bitmap_set(&st->touch_st.channels_bitmask, AT91_SAMA5D2_TOUCH_P_CHAN_IDX, 1); st->oversampling_ratio = AT91_OSR_1SAMPLES; ret = of_property_read_u32(pdev->dev.of_node, "atmel,min-sample-rate-hz", &st->soc_info.min_sample_rate); if (ret) { dev_err(&pdev->dev, "invalid or missing value for atmel,min-sample-rate-hz\n"); return ret; } ret = of_property_read_u32(pdev->dev.of_node, "atmel,max-sample-rate-hz", &st->soc_info.max_sample_rate); if (ret) { dev_err(&pdev->dev, "invalid or missing value for atmel,max-sample-rate-hz\n"); return ret; } ret = of_property_read_u32(pdev->dev.of_node, "atmel,startup-time-ms", &st->soc_info.startup_time); if (ret) { dev_err(&pdev->dev, "invalid or missing value for atmel,startup-time-ms\n"); return ret; } ret = of_property_read_u32(pdev->dev.of_node, "atmel,trigger-edge-type", &edge_type); if (ret) { dev_dbg(&pdev->dev, "atmel,trigger-edge-type not specified, only software trigger available\n"); } st->selected_trig = NULL; /* find the right trigger, or no trigger at all */ for (i = 0; i < AT91_SAMA5D2_HW_TRIG_CNT + 1; i++) if (at91_adc_trigger_list[i].edge_type == edge_type) { st->selected_trig = &at91_adc_trigger_list[i]; break; } if (!st->selected_trig) { dev_err(&pdev->dev, "invalid external trigger edge value\n"); return -EINVAL; } init_waitqueue_head(&st->wq_data_available); mutex_init(&st->lock); INIT_WORK(&st->touch_st.workq, at91_adc_workq_handler); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return -EINVAL; /* if we plan to use DMA, we need the physical address of the regs */ st->dma_st.phys_addr = res->start; st->base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(st->base)) return PTR_ERR(st->base); st->irq = platform_get_irq(pdev, 0); if (st->irq <= 0) { if (!st->irq) st->irq = -ENXIO; return st->irq; } st->per_clk = devm_clk_get(&pdev->dev, "adc_clk"); if (IS_ERR(st->per_clk)) return PTR_ERR(st->per_clk); st->reg = devm_regulator_get(&pdev->dev, "vddana"); if (IS_ERR(st->reg)) return PTR_ERR(st->reg); st->vref = devm_regulator_get(&pdev->dev, "vref"); if (IS_ERR(st->vref)) return PTR_ERR(st->vref); ret = devm_request_irq(&pdev->dev, st->irq, at91_adc_interrupt, 0, pdev->dev.driver->name, indio_dev); if (ret) return ret; ret = regulator_enable(st->reg); if (ret) return ret; ret = regulator_enable(st->vref); if (ret) goto reg_disable; st->vref_uv = regulator_get_voltage(st->vref); if (st->vref_uv <= 0) { ret = -EINVAL; goto vref_disable; } at91_adc_hw_init(st); ret = clk_prepare_enable(st->per_clk); if (ret) goto vref_disable; platform_set_drvdata(pdev, indio_dev); ret = at91_adc_buffer_init(indio_dev); if (ret < 0) { dev_err(&pdev->dev, "couldn't initialize the buffer.\n"); goto per_clk_disable_unprepare; } if (st->selected_trig->hw_trig) { ret = at91_adc_trigger_init(indio_dev); if (ret < 0) { dev_err(&pdev->dev, "couldn't setup the triggers.\n"); goto per_clk_disable_unprepare; } /* * Initially the iio buffer has a length of 2 and * a watermark of 1 */ st->dma_st.watermark = 1; iio_buffer_set_attrs(indio_dev->buffer, at91_adc_fifo_attributes); } if (dma_coerce_mask_and_coherent(&indio_dev->dev, DMA_BIT_MASK(32))) dev_info(&pdev->dev, "cannot set DMA mask to 32-bit\n"); ret = iio_device_register(indio_dev); if (ret < 0) goto dma_disable; if (st->selected_trig->hw_trig) dev_info(&pdev->dev, "setting up trigger as %s\n", st->selected_trig->name); dev_info(&pdev->dev, "version: %x\n", readl_relaxed(st->base + AT91_SAMA5D2_VERSION)); return 0; dma_disable: at91_adc_dma_disable(pdev); per_clk_disable_unprepare: clk_disable_unprepare(st->per_clk); vref_disable: regulator_disable(st->vref); reg_disable: regulator_disable(st->reg); return ret; } static int at91_adc_remove(struct platform_device *pdev) { struct iio_dev *indio_dev = platform_get_drvdata(pdev); struct at91_adc_state *st = iio_priv(indio_dev); iio_device_unregister(indio_dev); at91_adc_dma_disable(pdev); clk_disable_unprepare(st->per_clk); regulator_disable(st->vref); regulator_disable(st->reg); return 0; } static __maybe_unused int at91_adc_suspend(struct device *dev) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct at91_adc_state *st = iio_priv(indio_dev); /* * Do a sofware reset of the ADC before we go to suspend. * this will ensure that all pins are free from being muxed by the ADC * and can be used by for other devices. * Otherwise, ADC will hog them and we can't go to suspend mode. */ at91_adc_writel(st, AT91_SAMA5D2_CR, AT91_SAMA5D2_CR_SWRST); clk_disable_unprepare(st->per_clk); regulator_disable(st->vref); regulator_disable(st->reg); return pinctrl_pm_select_sleep_state(dev); } static __maybe_unused int at91_adc_resume(struct device *dev) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct at91_adc_state *st = iio_priv(indio_dev); int ret; ret = pinctrl_pm_select_default_state(dev); if (ret) goto resume_failed; ret = regulator_enable(st->reg); if (ret) goto resume_failed; ret = regulator_enable(st->vref); if (ret) goto reg_disable_resume; ret = clk_prepare_enable(st->per_clk); if (ret) goto vref_disable_resume; at91_adc_hw_init(st); /* reconfiguring trigger hardware state */ if (!iio_buffer_enabled(indio_dev)) return 0; /* check if we are enabling triggered buffer or the touchscreen */ if (bitmap_subset(indio_dev->active_scan_mask, &st->touch_st.channels_bitmask, AT91_SAMA5D2_MAX_CHAN_IDX + 1)) { /* touchscreen enabling */ return at91_adc_configure_touch(st, true); } else { return at91_adc_configure_trigger(st->trig, true); } /* not needed but more explicit */ return 0; vref_disable_resume: regulator_disable(st->vref); reg_disable_resume: regulator_disable(st->reg); resume_failed: dev_err(&indio_dev->dev, "failed to resume\n"); return ret; } static SIMPLE_DEV_PM_OPS(at91_adc_pm_ops, at91_adc_suspend, at91_adc_resume); static const struct of_device_id at91_adc_dt_match[] = { { .compatible = "atmel,sama5d2-adc", }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, at91_adc_dt_match); static struct platform_driver at91_adc_driver = { .probe = at91_adc_probe, .remove = at91_adc_remove, .driver = { .name = "at91-sama5d2_adc", .of_match_table = at91_adc_dt_match, .pm = &at91_adc_pm_ops, }, }; module_platform_driver(at91_adc_driver) MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@atmel.com>"); MODULE_DESCRIPTION("Atmel AT91 SAMA5D2 ADC"); MODULE_LICENSE("GPL v2");
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