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 if (adis->data->burst_max_speed_hz) 55 adis->xfer[0].speed_hz = adis->data->burst_max_speed_hz; 56 adis->xfer[1].rx_buf = adis->buffer; 57 adis->xfer[1].bits_per_word = 8; 58 adis->xfer[1].len = burst_length; 59 if (adis->data->burst_max_speed_hz) 60 adis->xfer[1].speed_hz = adis->data->burst_max_speed_hz; 61 62 spi_message_init(&adis->msg); 63 spi_message_add_tail(&adis->xfer[0], &adis->msg); 64 spi_message_add_tail(&adis->xfer[1], &adis->msg); 65 66 return 0; 67 } 68 69 int adis_update_scan_mode(struct iio_dev *indio_dev, 70 const unsigned long *scan_mask) 71 { 72 struct adis *adis = iio_device_get_drvdata(indio_dev); 73 const struct iio_chan_spec *chan; 74 unsigned int scan_count; 75 unsigned int i, j; 76 __be16 *tx, *rx; 77 78 kfree(adis->xfer); 79 kfree(adis->buffer); 80 81 if (adis->data->burst_len) 82 return adis_update_scan_mode_burst(indio_dev, scan_mask); 83 84 scan_count = indio_dev->scan_bytes / 2; 85 86 adis->xfer = kcalloc(scan_count + 1, sizeof(*adis->xfer), GFP_KERNEL); 87 if (!adis->xfer) 88 return -ENOMEM; 89 90 adis->buffer = kcalloc(indio_dev->scan_bytes, 2, GFP_KERNEL); 91 if (!adis->buffer) { 92 kfree(adis->xfer); 93 adis->xfer = NULL; 94 return -ENOMEM; 95 } 96 97 rx = adis->buffer; 98 tx = rx + scan_count; 99 100 spi_message_init(&adis->msg); 101 102 for (j = 0; j <= scan_count; j++) { 103 adis->xfer[j].bits_per_word = 8; 104 if (j != scan_count) 105 adis->xfer[j].cs_change = 1; 106 adis->xfer[j].len = 2; 107 adis->xfer[j].delay.value = adis->data->read_delay; 108 adis->xfer[j].delay.unit = SPI_DELAY_UNIT_USECS; 109 if (j < scan_count) 110 adis->xfer[j].tx_buf = &tx[j]; 111 if (j >= 1) 112 adis->xfer[j].rx_buf = &rx[j - 1]; 113 spi_message_add_tail(&adis->xfer[j], &adis->msg); 114 } 115 116 chan = indio_dev->channels; 117 for (i = 0; i < indio_dev->num_channels; i++, chan++) { 118 if (!test_bit(chan->scan_index, scan_mask)) 119 continue; 120 if (chan->scan_type.storagebits == 32) 121 *tx++ = cpu_to_be16((chan->address + 2) << 8); 122 *tx++ = cpu_to_be16(chan->address << 8); 123 } 124 125 return 0; 126 } 127 EXPORT_SYMBOL_GPL(adis_update_scan_mode); 128 129 static irqreturn_t adis_trigger_handler(int irq, void *p) 130 { 131 struct iio_poll_func *pf = p; 132 struct iio_dev *indio_dev = pf->indio_dev; 133 struct adis *adis = iio_device_get_drvdata(indio_dev); 134 int ret; 135 136 if (adis->data->has_paging) { 137 mutex_lock(&adis->state_lock); 138 if (adis->current_page != 0) { 139 adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID); 140 adis->tx[1] = 0; 141 ret = spi_write(adis->spi, adis->tx, 2); 142 if (ret) { 143 dev_err(&adis->spi->dev, "Failed to change device page: %d\n", ret); 144 mutex_unlock(&adis->state_lock); 145 goto irq_done; 146 } 147 148 adis->current_page = 0; 149 } 150 } 151 152 ret = spi_sync(adis->spi, &adis->msg); 153 if (adis->data->has_paging) 154 mutex_unlock(&adis->state_lock); 155 if (ret) { 156 dev_err(&adis->spi->dev, "Failed to read data: %d", ret); 157 goto irq_done; 158 } 159 160 iio_push_to_buffers_with_timestamp(indio_dev, adis->buffer, 161 pf->timestamp); 162 163 irq_done: 164 iio_trigger_notify_done(indio_dev->trig); 165 166 return IRQ_HANDLED; 167 } 168 169 static void adis_buffer_cleanup(void *arg) 170 { 171 struct adis *adis = arg; 172 173 kfree(adis->buffer); 174 kfree(adis->xfer); 175 } 176 177 /** 178 * devm_adis_setup_buffer_and_trigger() - Sets up buffer and trigger for 179 * the managed adis device 180 * @adis: The adis device 181 * @indio_dev: The IIO device 182 * @trigger_handler: Optional trigger handler, may be NULL. 183 * 184 * Returns 0 on success, a negative error code otherwise. 185 * 186 * This function sets up the buffer and trigger for a adis devices. If 187 * 'trigger_handler' is NULL the default trigger handler will be used. The 188 * default trigger handler will simply read the registers assigned to the 189 * currently active channels. 190 */ 191 int 192 devm_adis_setup_buffer_and_trigger(struct adis *adis, struct iio_dev *indio_dev, 193 irq_handler_t trigger_handler) 194 { 195 int ret; 196 197 if (!trigger_handler) 198 trigger_handler = adis_trigger_handler; 199 200 ret = devm_iio_triggered_buffer_setup(&adis->spi->dev, indio_dev, 201 &iio_pollfunc_store_time, 202 trigger_handler, NULL); 203 if (ret) 204 return ret; 205 206 if (adis->spi->irq) { 207 ret = devm_adis_probe_trigger(adis, indio_dev); 208 if (ret) 209 return ret; 210 } 211 212 return devm_add_action_or_reset(&adis->spi->dev, adis_buffer_cleanup, 213 adis); 214 } 215 EXPORT_SYMBOL_GPL(devm_adis_setup_buffer_and_trigger); 216 217