| /* |
| * Copyright (C) 2008 Jonathan Cameron |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * max1363_ring.c |
| */ |
| |
| #include <linux/interrupt.h> |
| #include <linux/slab.h> |
| #include <linux/kernel.h> |
| #include <linux/i2c.h> |
| #include <linux/bitops.h> |
| |
| #include "../iio.h" |
| #include "../buffer_generic.h" |
| #include "../ring_sw.h" |
| #include "../trigger_consumer.h" |
| |
| #include "max1363.h" |
| |
| int max1363_single_channel_from_ring(const long *mask, struct max1363_state *st) |
| { |
| struct iio_buffer *ring = iio_priv_to_dev(st)->buffer; |
| int count = 0, ret, index; |
| u8 *ring_data; |
| index = find_first_bit(mask, MAX1363_MAX_CHANNELS); |
| |
| if (!(test_bit(index, st->current_mode->modemask))) { |
| ret = -EBUSY; |
| goto error_ret; |
| } |
| |
| ring_data = kmalloc(ring->access->get_bytes_per_datum(ring), |
| GFP_KERNEL); |
| if (ring_data == NULL) { |
| ret = -ENOMEM; |
| goto error_ret; |
| } |
| ret = ring->access->read_last(ring, ring_data); |
| if (ret) |
| goto error_free_ring_data; |
| /* Need a count of channels prior to this one */ |
| |
| count = bitmap_weight(mask, index - 1); |
| if (st->chip_info->bits != 8) |
| ret = ((int)(ring_data[count*2 + 0] & 0x0F) << 8) |
| + (int)(ring_data[count*2 + 1]); |
| else |
| ret = ring_data[count]; |
| |
| error_free_ring_data: |
| kfree(ring_data); |
| error_ret: |
| return ret; |
| } |
| |
| |
| /** |
| * max1363_ring_preenable() - setup the parameters of the ring before enabling |
| * |
| * The complex nature of the setting of the nuber of bytes per datum is due |
| * to this driver currently ensuring that the timestamp is stored at an 8 |
| * byte boundary. |
| **/ |
| static int max1363_ring_preenable(struct iio_dev *indio_dev) |
| { |
| struct max1363_state *st = iio_priv(indio_dev); |
| struct iio_buffer *ring = indio_dev->buffer; |
| size_t d_size = 0; |
| unsigned long numvals; |
| |
| /* |
| * Need to figure out the current mode based upon the requested |
| * scan mask in iio_dev |
| */ |
| st->current_mode = max1363_match_mode(ring->scan_mask, |
| st->chip_info); |
| if (!st->current_mode) |
| return -EINVAL; |
| |
| max1363_set_scan_mode(st); |
| |
| numvals = bitmap_weight(st->current_mode->modemask, |
| indio_dev->masklength); |
| if (ring->access->set_bytes_per_datum) { |
| if (ring->scan_timestamp) |
| d_size += sizeof(s64); |
| if (st->chip_info->bits != 8) |
| d_size += numvals*2; |
| else |
| d_size += numvals; |
| if (ring->scan_timestamp && (d_size % 8)) |
| d_size += 8 - (d_size % 8); |
| ring->access->set_bytes_per_datum(ring, d_size); |
| } |
| |
| return 0; |
| } |
| |
| static irqreturn_t max1363_trigger_handler(int irq, void *p) |
| { |
| struct iio_poll_func *pf = p; |
| struct iio_dev *indio_dev = pf->indio_dev; |
| struct max1363_state *st = iio_priv(indio_dev); |
| s64 time_ns; |
| __u8 *rxbuf; |
| int b_sent; |
| size_t d_size; |
| unsigned long numvals = bitmap_weight(st->current_mode->modemask, |
| MAX1363_MAX_CHANNELS); |
| |
| /* Ensure the timestamp is 8 byte aligned */ |
| if (st->chip_info->bits != 8) |
| d_size = numvals*2 + sizeof(s64); |
| else |
| d_size = numvals + sizeof(s64); |
| if (d_size % sizeof(s64)) |
| d_size += sizeof(s64) - (d_size % sizeof(s64)); |
| |
| /* Monitor mode prevents reading. Whilst not currently implemented |
| * might as well have this test in here in the meantime as it does |
| * no harm. |
| */ |
| if (numvals == 0) |
| return IRQ_HANDLED; |
| |
| rxbuf = kmalloc(d_size, GFP_KERNEL); |
| if (rxbuf == NULL) |
| return -ENOMEM; |
| if (st->chip_info->bits != 8) |
| b_sent = i2c_master_recv(st->client, rxbuf, numvals*2); |
| else |
| b_sent = i2c_master_recv(st->client, rxbuf, numvals); |
| if (b_sent < 0) |
| goto done; |
| |
| time_ns = iio_get_time_ns(); |
| |
| memcpy(rxbuf + d_size - sizeof(s64), &time_ns, sizeof(time_ns)); |
| |
| indio_dev->buffer->access->store_to(indio_dev->buffer, rxbuf, time_ns); |
| done: |
| iio_trigger_notify_done(indio_dev->trig); |
| kfree(rxbuf); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static const struct iio_buffer_setup_ops max1363_ring_setup_ops = { |
| .postenable = &iio_triggered_buffer_postenable, |
| .preenable = &max1363_ring_preenable, |
| .predisable = &iio_triggered_buffer_predisable, |
| }; |
| |
| int max1363_register_ring_funcs_and_init(struct iio_dev *indio_dev) |
| { |
| struct max1363_state *st = iio_priv(indio_dev); |
| int ret = 0; |
| |
| indio_dev->buffer = iio_sw_rb_allocate(indio_dev); |
| if (!indio_dev->buffer) { |
| ret = -ENOMEM; |
| goto error_ret; |
| } |
| indio_dev->pollfunc = iio_alloc_pollfunc(NULL, |
| &max1363_trigger_handler, |
| IRQF_ONESHOT, |
| indio_dev, |
| "%s_consumer%d", |
| st->client->name, |
| indio_dev->id); |
| if (indio_dev->pollfunc == NULL) { |
| ret = -ENOMEM; |
| goto error_deallocate_sw_rb; |
| } |
| /* Effectively select the ring buffer implementation */ |
| indio_dev->buffer->access = &ring_sw_access_funcs; |
| /* Ring buffer functions - here trigger setup related */ |
| indio_dev->buffer->setup_ops = &max1363_ring_setup_ops; |
| |
| /* Flag that polled ring buffering is possible */ |
| indio_dev->modes |= INDIO_BUFFER_TRIGGERED; |
| |
| return 0; |
| |
| error_deallocate_sw_rb: |
| iio_sw_rb_free(indio_dev->buffer); |
| error_ret: |
| return ret; |
| } |
| |
| void max1363_ring_cleanup(struct iio_dev *indio_dev) |
| { |
| /* ensure that the trigger has been detached */ |
| iio_dealloc_pollfunc(indio_dev->pollfunc); |
| iio_sw_rb_free(indio_dev->buffer); |
| } |