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
adis_update_scan_mode_burst(struct iio_dev * indio_dev,const unsigned long * scan_mask)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
adis_update_scan_mode(struct iio_dev * indio_dev,const unsigned long * scan_mask)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_NS_GPL(adis_update_scan_mode, IIO_ADISLIB);
124
adis_trigger_handler(int irq,void * p)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->data->has_paging) {
133 mutex_lock(&adis->state_lock);
134 if (adis->current_page != 0) {
135 adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID);
136 adis->tx[1] = 0;
137 spi_write(adis->spi, adis->tx, 2);
138 }
139 }
140
141 ret = spi_sync(adis->spi, &adis->msg);
142 if (ret)
143 dev_err(&adis->spi->dev, "Failed to read data: %d", ret);
144
145
146 if (adis->data->has_paging) {
147 adis->current_page = 0;
148 mutex_unlock(&adis->state_lock);
149 }
150
151 iio_push_to_buffers_with_timestamp(indio_dev, adis->buffer,
152 pf->timestamp);
153
154 iio_trigger_notify_done(indio_dev->trig);
155
156 return IRQ_HANDLED;
157 }
158
adis_buffer_cleanup(void * arg)159 static void adis_buffer_cleanup(void *arg)
160 {
161 struct adis *adis = arg;
162
163 kfree(adis->buffer);
164 kfree(adis->xfer);
165 }
166
167 /**
168 * devm_adis_setup_buffer_and_trigger() - Sets up buffer and trigger for
169 * the managed adis device
170 * @adis: The adis device
171 * @indio_dev: The IIO device
172 * @trigger_handler: Optional trigger handler, may be NULL.
173 *
174 * Returns 0 on success, a negative error code otherwise.
175 *
176 * This function sets up the buffer and trigger for a adis devices. If
177 * 'trigger_handler' is NULL the default trigger handler will be used. The
178 * default trigger handler will simply read the registers assigned to the
179 * currently active channels.
180 */
181 int
devm_adis_setup_buffer_and_trigger(struct adis * adis,struct iio_dev * indio_dev,irq_handler_t trigger_handler)182 devm_adis_setup_buffer_and_trigger(struct adis *adis, struct iio_dev *indio_dev,
183 irq_handler_t trigger_handler)
184 {
185 int ret;
186
187 if (!trigger_handler)
188 trigger_handler = adis_trigger_handler;
189
190 ret = devm_iio_triggered_buffer_setup(&adis->spi->dev, indio_dev,
191 &iio_pollfunc_store_time,
192 trigger_handler, NULL);
193 if (ret)
194 return ret;
195
196 if (adis->spi->irq) {
197 ret = devm_adis_probe_trigger(adis, indio_dev);
198 if (ret)
199 return ret;
200 }
201
202 return devm_add_action_or_reset(&adis->spi->dev, adis_buffer_cleanup,
203 adis);
204 }
205 EXPORT_SYMBOL_NS_GPL(devm_adis_setup_buffer_and_trigger, IIO_ADISLIB);
206
207