industrialio-buffer.c (527c465a3c8716d93201ae34b7fc52679610596d) industrialio-buffer.c (0123635a77f72e0787f6f8b3ac796a40f796fcc4)
1/* The industrial I/O core
2 *
3 * Copyright (c) 2008 Jonathan Cameron
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
8 *

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66 to_wait = min_t(size_t, to_wait, 1);
67 to_flush = 0;
68 }
69
70 avail = iio_buffer_data_available(buf);
71
72 if (avail >= to_wait) {
73 /* force a flush for non-blocking reads */
1/* The industrial I/O core
2 *
3 * Copyright (c) 2008 Jonathan Cameron
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published by
7 * the Free Software Foundation.
8 *

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66 to_wait = min_t(size_t, to_wait, 1);
67 to_flush = 0;
68 }
69
70 avail = iio_buffer_data_available(buf);
71
72 if (avail >= to_wait) {
73 /* force a flush for non-blocking reads */
74 if (!to_wait && !avail && to_flush)
75 iio_buffer_flush_hwfifo(indio_dev, buf, to_flush);
74 if (!to_wait && avail < to_flush)
75 iio_buffer_flush_hwfifo(indio_dev, buf,
76 to_flush - avail);
76 return true;
77 }
78
79 if (to_flush)
80 flushed = iio_buffer_flush_hwfifo(indio_dev, buf,
81 to_wait - avail);
82 if (flushed <= 0)
83 return false;
84
85 if (avail + flushed >= to_wait)
86 return true;
87
88 return false;
89}
90
91/**
92 * iio_buffer_read_first_n_outer() - chrdev read for buffer access
77 return true;
78 }
79
80 if (to_flush)
81 flushed = iio_buffer_flush_hwfifo(indio_dev, buf,
82 to_wait - avail);
83 if (flushed <= 0)
84 return false;
85
86 if (avail + flushed >= to_wait)
87 return true;
88
89 return false;
90}
91
92/**
93 * iio_buffer_read_first_n_outer() - chrdev read for buffer access
94 * @filp: File structure pointer for the char device
95 * @buf: Destination buffer for iio buffer read
96 * @n: First n bytes to read
97 * @f_ps: Long offset provided by the user as a seek position
93 *
94 * This function relies on all buffer implementations having an
95 * iio_buffer as their first element.
98 *
99 * This function relies on all buffer implementations having an
100 * iio_buffer as their first element.
101 *
102 * Return: negative values corresponding to error codes or ret != 0
103 * for ending the reading activity
96 **/
97ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf,
98 size_t n, loff_t *f_ps)
99{
100 struct iio_dev *indio_dev = filp->private_data;
101 struct iio_buffer *rb = indio_dev->buffer;
102 size_t datum_size;
104 **/
105ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf,
106 size_t n, loff_t *f_ps)
107{
108 struct iio_dev *indio_dev = filp->private_data;
109 struct iio_buffer *rb = indio_dev->buffer;
110 size_t datum_size;
103 size_t to_wait = 0;
104 size_t to_read;
111 size_t to_wait;
105 int ret;
106
107 if (!indio_dev->info)
108 return -ENODEV;
109
110 if (!rb || !rb->access->read_first_n)
111 return -EINVAL;
112
113 datum_size = rb->bytes_per_datum;
114
115 /*
116 * If datum_size is 0 there will never be anything to read from the
117 * buffer, so signal end of file now.
118 */
119 if (!datum_size)
120 return 0;
121
112 int ret;
113
114 if (!indio_dev->info)
115 return -ENODEV;
116
117 if (!rb || !rb->access->read_first_n)
118 return -EINVAL;
119
120 datum_size = rb->bytes_per_datum;
121
122 /*
123 * If datum_size is 0 there will never be anything to read from the
124 * buffer, so signal end of file now.
125 */
126 if (!datum_size)
127 return 0;
128
122 to_read = min_t(size_t, n / datum_size, rb->watermark);
129 if (filp->f_flags & O_NONBLOCK)
130 to_wait = 0;
131 else
132 to_wait = min_t(size_t, n / datum_size, rb->watermark);
123
133
124 if (!(filp->f_flags & O_NONBLOCK))
125 to_wait = to_read;
126
127 do {
128 ret = wait_event_interruptible(rb->pollq,
134 do {
135 ret = wait_event_interruptible(rb->pollq,
129 iio_buffer_ready(indio_dev, rb, to_wait, to_read));
136 iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size));
130 if (ret)
131 return ret;
132
133 if (!indio_dev->info)
134 return -ENODEV;
135
136 ret = rb->access->read_first_n(rb, n, buf);
137 if (ret == 0 && (filp->f_flags & O_NONBLOCK))
138 ret = -EAGAIN;
139 } while (ret == 0);
140
141 return ret;
142}
143
144/**
145 * iio_buffer_poll() - poll the buffer to find out if it has data
137 if (ret)
138 return ret;
139
140 if (!indio_dev->info)
141 return -ENODEV;
142
143 ret = rb->access->read_first_n(rb, n, buf);
144 if (ret == 0 && (filp->f_flags & O_NONBLOCK))
145 ret = -EAGAIN;
146 } while (ret == 0);
147
148 return ret;
149}
150
151/**
152 * iio_buffer_poll() - poll the buffer to find out if it has data
153 * @filp: File structure pointer for device access
154 * @wait: Poll table structure pointer for which the driver adds
155 * a wait queue
156 *
157 * Return: (POLLIN | POLLRDNORM) if data is available for reading
158 * or 0 for other cases
146 */
147unsigned int iio_buffer_poll(struct file *filp,
148 struct poll_table_struct *wait)
149{
150 struct iio_dev *indio_dev = filp->private_data;
151 struct iio_buffer *rb = indio_dev->buffer;
152
153 if (!indio_dev->info)

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1131 return 0;
1132
1133 /* Ensure return value is 0 or 1. */
1134 return !!test_bit(bit, buffer->scan_mask);
1135};
1136EXPORT_SYMBOL_GPL(iio_scan_mask_query);
1137
1138/**
159 */
160unsigned int iio_buffer_poll(struct file *filp,
161 struct poll_table_struct *wait)
162{
163 struct iio_dev *indio_dev = filp->private_data;
164 struct iio_buffer *rb = indio_dev->buffer;
165
166 if (!indio_dev->info)

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1144 return 0;
1145
1146 /* Ensure return value is 0 or 1. */
1147 return !!test_bit(bit, buffer->scan_mask);
1148};
1149EXPORT_SYMBOL_GPL(iio_scan_mask_query);
1150
1151/**
1139 * struct iio_demux_table() - table describing demux memcpy ops
1152 * struct iio_demux_table - table describing demux memcpy ops
1140 * @from: index to copy from
1141 * @to: index to copy to
1142 * @length: how many bytes to copy
1143 * @l: list head used for management
1144 */
1145struct iio_demux_table {
1146 unsigned from;
1147 unsigned to;

--- 225 unchanged lines hidden --- 		1153 * @from: index to copy from
1154 * @to: index to copy to
1155 * @length: how many bytes to copy
1156 * @l: list head used for management
1157 */
1158struct iio_demux_table {
1159 unsigned from;
1160 unsigned to;

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