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 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
adis_update_scan_mode(struct iio_dev * indio_dev,const unsigned long * scan_mask)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_NS_GPL(adis_update_scan_mode, IIO_ADISLIB);
128
adis_trigger_handler(int irq,void * p)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
adis_buffer_cleanup(void * arg)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
devm_adis_setup_buffer_and_trigger(struct adis * adis,struct iio_dev * indio_dev,irq_handler_t trigger_handler)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_NS_GPL(devm_adis_setup_buffer_and_trigger, IIO_ADISLIB);
216
217