1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2012 Analog Devices, Inc. 4 * Author: Lars-Peter Clausen <lars@metafoo.de> 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/export.h> 9 #include <linux/module.h> 10 #include <linux/iio/iio.h> 11 #include <linux/iio/buffer.h> 12 #include <linux/iio/kfifo_buf.h> 13 #include <linux/iio/triggered_buffer.h> 14 #include <linux/iio/trigger_consumer.h> 15 16 /** 17 * iio_triggered_buffer_setup() - Setup triggered buffer and pollfunc 18 * @indio_dev: IIO device structure 19 * @h: Function which will be used as pollfunc top half 20 * @thread: Function which will be used as pollfunc bottom half 21 * @setup_ops: Buffer setup functions to use for this device. 22 * If NULL the default setup functions for triggered 23 * buffers will be used. 24 * 25 * This function combines some common tasks which will normally be performed 26 * when setting up a triggered buffer. It will allocate the buffer and the 27 * pollfunc. 28 * 29 * Before calling this function the indio_dev structure should already be 30 * completely initialized, but not yet registered. In practice this means that 31 * this function should be called right before iio_device_register(). 32 * 33 * To free the resources allocated by this function call 34 * iio_triggered_buffer_cleanup(). 35 */ 36 int iio_triggered_buffer_setup(struct iio_dev *indio_dev, 37 irqreturn_t (*h)(int irq, void *p), 38 irqreturn_t (*thread)(int irq, void *p), 39 const struct iio_buffer_setup_ops *setup_ops) 40 { 41 struct iio_buffer *buffer; 42 int ret; 43 44 buffer = iio_kfifo_allocate(); 45 if (!buffer) { 46 ret = -ENOMEM; 47 goto error_ret; 48 } 49 50 iio_device_attach_buffer(indio_dev, buffer); 51 52 indio_dev->pollfunc = iio_alloc_pollfunc(h, 53 thread, 54 IRQF_ONESHOT, 55 indio_dev, 56 "%s_consumer%d", 57 indio_dev->name, 58 indio_dev->id); 59 if (indio_dev->pollfunc == NULL) { 60 ret = -ENOMEM; 61 goto error_kfifo_free; 62 } 63 64 /* Ring buffer functions - here trigger setup related */ 65 indio_dev->setup_ops = setup_ops; 66 67 /* Flag that polled ring buffering is possible */ 68 indio_dev->modes |= INDIO_BUFFER_TRIGGERED; 69 70 return 0; 71 72 error_kfifo_free: 73 iio_kfifo_free(indio_dev->buffer); 74 error_ret: 75 return ret; 76 } 77 EXPORT_SYMBOL(iio_triggered_buffer_setup); 78 79 /** 80 * iio_triggered_buffer_cleanup() - Free resources allocated by iio_triggered_buffer_setup() 81 * @indio_dev: IIO device structure 82 */ 83 void iio_triggered_buffer_cleanup(struct iio_dev *indio_dev) 84 { 85 iio_dealloc_pollfunc(indio_dev->pollfunc); 86 iio_kfifo_free(indio_dev->buffer); 87 } 88 EXPORT_SYMBOL(iio_triggered_buffer_cleanup); 89 90 static void devm_iio_triggered_buffer_clean(struct device *dev, void *res) 91 { 92 iio_triggered_buffer_cleanup(*(struct iio_dev **)res); 93 } 94 95 int devm_iio_triggered_buffer_setup(struct device *dev, 96 struct iio_dev *indio_dev, 97 irqreturn_t (*h)(int irq, void *p), 98 irqreturn_t (*thread)(int irq, void *p), 99 const struct iio_buffer_setup_ops *ops) 100 { 101 struct iio_dev **ptr; 102 int ret; 103 104 ptr = devres_alloc(devm_iio_triggered_buffer_clean, sizeof(*ptr), 105 GFP_KERNEL); 106 if (!ptr) 107 return -ENOMEM; 108 109 *ptr = indio_dev; 110 111 ret = iio_triggered_buffer_setup(indio_dev, h, thread, ops); 112 if (!ret) 113 devres_add(dev, ptr); 114 else 115 devres_free(ptr); 116 117 return ret; 118 } 119 EXPORT_SYMBOL_GPL(devm_iio_triggered_buffer_setup); 120 121 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); 122 MODULE_DESCRIPTION("IIO helper functions for setting up triggered buffers"); 123 MODULE_LICENSE("GPL"); 124