2 * Copyright (C) 2008 Jonathan Cameron
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
11 #include <linux/interrupt.h>
12 #include <linux/slab.h>
13 #include <linux/kernel.h>
14 #include <linux/i2c.h>
15 #include <linux/bitops.h>
18 #include "../ring_generic.h"
19 #include "../ring_sw.h"
20 #include "../trigger_consumer.h"
24 int max1363_single_channel_from_ring(const long *mask, struct max1363_state *st)
26 struct iio_ring_buffer *ring = iio_priv_to_dev(st)->ring;
27 int count = 0, ret, index;
29 index = find_first_bit(mask, MAX1363_MAX_CHANNELS);
31 if (!(test_bit(index, st->current_mode->modemask))) {
36 ring_data = kmalloc(ring->access->get_bytes_per_datum(ring),
38 if (ring_data == NULL) {
42 ret = ring->access->read_last(ring, ring_data);
44 goto error_free_ring_data;
45 /* Need a count of channels prior to this one */
47 count = bitmap_weight(mask, index - 1);
48 if (st->chip_info->bits != 8)
49 ret = ((int)(ring_data[count*2 + 0] & 0x0F) << 8)
50 + (int)(ring_data[count*2 + 1]);
52 ret = ring_data[count];
62 * max1363_ring_preenable() - setup the parameters of the ring before enabling
64 * The complex nature of the setting of the nuber of bytes per datum is due
65 * to this driver currently ensuring that the timestamp is stored at an 8
68 static int max1363_ring_preenable(struct iio_dev *indio_dev)
70 struct max1363_state *st = iio_priv(indio_dev);
71 struct iio_ring_buffer *ring = indio_dev->ring;
73 unsigned long numvals;
76 * Need to figure out the current mode based upon the requested
77 * scan mask in iio_dev
79 st->current_mode = max1363_match_mode(ring->scan_mask,
81 if (!st->current_mode)
84 max1363_set_scan_mode(st);
86 numvals = bitmap_weight(st->current_mode->modemask,
87 indio_dev->masklength);
88 if (ring->access->set_bytes_per_datum) {
89 if (ring->scan_timestamp)
90 d_size += sizeof(s64);
91 if (st->chip_info->bits != 8)
95 if (ring->scan_timestamp && (d_size % 8))
96 d_size += 8 - (d_size % 8);
97 ring->access->set_bytes_per_datum(ring, d_size);
103 static irqreturn_t max1363_trigger_handler(int irq, void *p)
105 struct iio_poll_func *pf = p;
106 struct iio_dev *indio_dev = pf->indio_dev;
107 struct max1363_state *st = iio_priv(indio_dev);
112 unsigned long numvals = bitmap_weight(st->current_mode->modemask,
113 MAX1363_MAX_CHANNELS);
115 /* Ensure the timestamp is 8 byte aligned */
116 if (st->chip_info->bits != 8)
117 d_size = numvals*2 + sizeof(s64);
119 d_size = numvals + sizeof(s64);
120 if (d_size % sizeof(s64))
121 d_size += sizeof(s64) - (d_size % sizeof(s64));
123 /* Monitor mode prevents reading. Whilst not currently implemented
124 * might as well have this test in here in the meantime as it does
130 rxbuf = kmalloc(d_size, GFP_KERNEL);
133 if (st->chip_info->bits != 8)
134 b_sent = i2c_master_recv(st->client, rxbuf, numvals*2);
136 b_sent = i2c_master_recv(st->client, rxbuf, numvals);
140 time_ns = iio_get_time_ns();
142 memcpy(rxbuf + d_size - sizeof(s64), &time_ns, sizeof(time_ns));
144 indio_dev->ring->access->store_to(indio_dev->ring, rxbuf, time_ns);
146 iio_trigger_notify_done(indio_dev->trig);
152 static const struct iio_ring_setup_ops max1363_ring_setup_ops = {
153 .postenable = &iio_triggered_buffer_postenable,
154 .preenable = &max1363_ring_preenable,
155 .predisable = &iio_triggered_buffer_predisable,
158 int max1363_register_ring_funcs_and_init(struct iio_dev *indio_dev)
160 struct max1363_state *st = iio_priv(indio_dev);
163 indio_dev->ring = iio_sw_rb_allocate(indio_dev);
164 if (!indio_dev->ring) {
168 indio_dev->pollfunc = iio_alloc_pollfunc(NULL,
169 &max1363_trigger_handler,
175 if (indio_dev->pollfunc == NULL) {
177 goto error_deallocate_sw_rb;
179 /* Effectively select the ring buffer implementation */
180 indio_dev->ring->access = &ring_sw_access_funcs;
181 /* Ring buffer functions - here trigger setup related */
182 indio_dev->ring->setup_ops = &max1363_ring_setup_ops;
184 /* Flag that polled ring buffering is possible */
185 indio_dev->modes |= INDIO_RING_TRIGGERED;
189 error_deallocate_sw_rb:
190 iio_sw_rb_free(indio_dev->ring);
195 void max1363_ring_cleanup(struct iio_dev *indio_dev)
197 /* ensure that the trigger has been detached */
198 iio_dealloc_pollfunc(indio_dev->pollfunc);
199 iio_sw_rb_free(indio_dev->ring);