1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Common library for ADIS16XXX devices 4 * 5 * Copyright 2012 Analog Devices Inc. 6 * Author: Lars-Peter Clausen <lars@metafoo.de> 7 */ 8 9 #include <linux/export.h> 10 #include <linux/interrupt.h> 11 #include <linux/mutex.h> 12 #include <linux/kernel.h> 13 #include <linux/spi/spi.h> 14 #include <linux/slab.h> 15 16 #include <linux/iio/iio.h> 17 #include <linux/iio/buffer.h> 18 #include <linux/iio/trigger_consumer.h> 19 #include <linux/iio/triggered_buffer.h> 20 #include <linux/iio/imu/adis.h> 21 22 static int adis_update_scan_mode_burst(struct iio_dev *indio_dev, 23 const unsigned long *scan_mask) 24 { 25 struct adis *adis = iio_device_get_drvdata(indio_dev); 26 unsigned int burst_length, burst_max_length; 27 u8 *tx; 28 29 burst_length = adis->data->burst_len + adis->burst_extra_len; 30 31 if (adis->data->burst_max_len) 32 burst_max_length = adis->data->burst_max_len; 33 else 34 burst_max_length = burst_length; 35 36 adis->xfer = kcalloc(2, sizeof(*adis->xfer), GFP_KERNEL); 37 if (!adis->xfer) 38 return -ENOMEM; 39 40 adis->buffer = kzalloc(burst_max_length + sizeof(u16), GFP_KERNEL); 41 if (!adis->buffer) { 42 kfree(adis->xfer); 43 adis->xfer = NULL; 44 return -ENOMEM; 45 } 46 47 tx = adis->buffer + burst_max_length; 48 tx[0] = ADIS_READ_REG(adis->data->burst_reg_cmd); 49 tx[1] = 0; 50 51 adis->xfer[0].tx_buf = tx; 52 adis->xfer[0].bits_per_word = 8; 53 adis->xfer[0].len = 2; 54 adis->xfer[1].rx_buf = adis->buffer; 55 adis->xfer[1].bits_per_word = 8; 56 adis->xfer[1].len = burst_length; 57 58 spi_message_init(&adis->msg); 59 spi_message_add_tail(&adis->xfer[0], &adis->msg); 60 spi_message_add_tail(&adis->xfer[1], &adis->msg); 61 62 return 0; 63 } 64 65 int adis_update_scan_mode(struct iio_dev *indio_dev, 66 const unsigned long *scan_mask) 67 { 68 struct adis *adis = iio_device_get_drvdata(indio_dev); 69 const struct iio_chan_spec *chan; 70 unsigned int scan_count; 71 unsigned int i, j; 72 __be16 *tx, *rx; 73 74 kfree(adis->xfer); 75 kfree(adis->buffer); 76 77 if (adis->data->burst_len) 78 return adis_update_scan_mode_burst(indio_dev, scan_mask); 79 80 scan_count = indio_dev->scan_bytes / 2; 81 82 adis->xfer = kcalloc(scan_count + 1, sizeof(*adis->xfer), GFP_KERNEL); 83 if (!adis->xfer) 84 return -ENOMEM; 85 86 adis->buffer = kcalloc(indio_dev->scan_bytes, 2, GFP_KERNEL); 87 if (!adis->buffer) { 88 kfree(adis->xfer); 89 adis->xfer = NULL; 90 return -ENOMEM; 91 } 92 93 rx = adis->buffer; 94 tx = rx + scan_count; 95 96 spi_message_init(&adis->msg); 97 98 for (j = 0; j <= scan_count; j++) { 99 adis->xfer[j].bits_per_word = 8; 100 if (j != scan_count) 101 adis->xfer[j].cs_change = 1; 102 adis->xfer[j].len = 2; 103 adis->xfer[j].delay.value = adis->data->read_delay; 104 adis->xfer[j].delay.unit = SPI_DELAY_UNIT_USECS; 105 if (j < scan_count) 106 adis->xfer[j].tx_buf = &tx[j]; 107 if (j >= 1) 108 adis->xfer[j].rx_buf = &rx[j - 1]; 109 spi_message_add_tail(&adis->xfer[j], &adis->msg); 110 } 111 112 chan = indio_dev->channels; 113 for (i = 0; i < indio_dev->num_channels; i++, chan++) { 114 if (!test_bit(chan->scan_index, scan_mask)) 115 continue; 116 if (chan->scan_type.storagebits == 32) 117 *tx++ = cpu_to_be16((chan->address + 2) << 8); 118 *tx++ = cpu_to_be16(chan->address << 8); 119 } 120 121 return 0; 122 } 123 EXPORT_SYMBOL_GPL(adis_update_scan_mode); 124 125 static irqreturn_t adis_trigger_handler(int irq, void *p) 126 { 127 struct iio_poll_func *pf = p; 128 struct iio_dev *indio_dev = pf->indio_dev; 129 struct adis *adis = iio_device_get_drvdata(indio_dev); 130 int ret; 131 132 if (!adis->buffer) 133 return -ENOMEM; 134 135 if (adis->data->has_paging) { 136 mutex_lock(&adis->state_lock); 137 if (adis->current_page != 0) { 138 adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID); 139 adis->tx[1] = 0; 140 spi_write(adis->spi, adis->tx, 2); 141 } 142 } 143 144 ret = spi_sync(adis->spi, &adis->msg); 145 if (ret) 146 dev_err(&adis->spi->dev, "Failed to read data: %d", ret); 147 148 149 if (adis->data->has_paging) { 150 adis->current_page = 0; 151 mutex_unlock(&adis->state_lock); 152 } 153 154 iio_push_to_buffers_with_timestamp(indio_dev, adis->buffer, 155 pf->timestamp); 156 157 iio_trigger_notify_done(indio_dev->trig); 158 159 return IRQ_HANDLED; 160 } 161 162 static void adis_buffer_cleanup(void *arg) 163 { 164 struct adis *adis = arg; 165 166 kfree(adis->buffer); 167 kfree(adis->xfer); 168 } 169 170 /** 171 * devm_adis_setup_buffer_and_trigger() - Sets up buffer and trigger for 172 * the managed adis device 173 * @adis: The adis device 174 * @indio_dev: The IIO device 175 * @trigger_handler: Optional trigger handler, may be NULL. 176 * 177 * Returns 0 on success, a negative error code otherwise. 178 * 179 * This function sets up the buffer and trigger for a adis devices. If 180 * 'trigger_handler' is NULL the default trigger handler will be used. The 181 * default trigger handler will simply read the registers assigned to the 182 * currently active channels. 183 */ 184 int 185 devm_adis_setup_buffer_and_trigger(struct adis *adis, struct iio_dev *indio_dev, 186 irq_handler_t trigger_handler) 187 { 188 int ret; 189 190 if (!trigger_handler) 191 trigger_handler = adis_trigger_handler; 192 193 ret = devm_iio_triggered_buffer_setup(&adis->spi->dev, indio_dev, 194 &iio_pollfunc_store_time, 195 trigger_handler, NULL); 196 if (ret) 197 return ret; 198 199 if (adis->spi->irq) { 200 ret = devm_adis_probe_trigger(adis, indio_dev); 201 if (ret) 202 return ret; 203 } 204 205 return devm_add_action_or_reset(&adis->spi->dev, adis_buffer_cleanup, 206 adis); 207 } 208 EXPORT_SYMBOL_GPL(devm_adis_setup_buffer_and_trigger); 209 210