| /* |
| * Atmel ADC driver for SAMA5D2 devices and compatible. |
| * |
| * Copyright (C) 2015 Atmel, |
| * 2015 Ludovic Desroches <ludovic.desroches@atmel.com> |
| * |
| * This software is licensed under the terms of the GNU General Public |
| * License version 2, as published by the Free Software Foundation, and |
| * may be copied, distributed, and modified under those terms. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #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); |
| u32 cor; |
| |
| if (!chan) |
| continue; |
| /* these channel types cannot be handled by this trigger */ |
| if (chan->type == IIO_POSITIONRELATIVE || |
| chan->type == IIO_PRESSURE) |
| continue; |
| |
| if (state) { |
| cor = at91_adc_readl(st, AT91_SAMA5D2_COR); |
| |
| if (chan->differential) |
| cor |= (BIT(chan->channel) | |
| BIT(chan->channel2)) << |
| AT91_SAMA5D2_COR_DIFF_OFFSET; |
| else |
| cor &= ~(BIT(chan->channel) << |
| AT91_SAMA5D2_COR_DIFF_OFFSET); |
| |
| at91_adc_writel(st, AT91_SAMA5D2_COR, cor); |
| } |
| |
| 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, |
| chan->scan_type.realbits - 1); |
| 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 = |
| platform_get_drvdata(to_platform_device(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 = |
| platform_get_drvdata(to_platform_device(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 = |
| platform_get_drvdata(to_platform_device(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 = |
| platform_get_drvdata(to_platform_device(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"); |