202 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com>4 <http://rt2x00.serialmonkey.com>5 6 */7 8/*9 Module: rt2x00mmio10 Abstract: rt2x00 generic mmio device routines.11 */12 13#include <linux/dma-mapping.h>14#include <linux/kernel.h>15#include <linux/module.h>16#include <linux/slab.h>17 18#include "rt2x00.h"19#include "rt2x00mmio.h"20 21/*22 * Register access.23 */24int rt2x00mmio_regbusy_read(struct rt2x00_dev *rt2x00dev,25 const unsigned int offset,26 const struct rt2x00_field32 field,27 u32 *reg)28{29 unsigned int i;30 31 if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))32 return 0;33 34 for (i = 0; i < REGISTER_BUSY_COUNT; i++) {35 *reg = rt2x00mmio_register_read(rt2x00dev, offset);36 if (!rt2x00_get_field32(*reg, field))37 return 1;38 udelay(REGISTER_BUSY_DELAY);39 }40 41 printk_once(KERN_ERR "%s() Indirect register access failed: "42 "offset=0x%.08x, value=0x%.08x\n", __func__, offset, *reg);43 *reg = ~0;44 45 return 0;46}47EXPORT_SYMBOL_GPL(rt2x00mmio_regbusy_read);48 49bool rt2x00mmio_rxdone(struct rt2x00_dev *rt2x00dev)50{51 struct data_queue *queue = rt2x00dev->rx;52 struct queue_entry *entry;53 struct queue_entry_priv_mmio *entry_priv;54 struct skb_frame_desc *skbdesc;55 int max_rx = 16;56 57 while (--max_rx) {58 entry = rt2x00queue_get_entry(queue, Q_INDEX);59 entry_priv = entry->priv_data;60 61 if (rt2x00dev->ops->lib->get_entry_state(entry))62 break;63 64 /*65 * Fill in desc fields of the skb descriptor66 */67 skbdesc = get_skb_frame_desc(entry->skb);68 skbdesc->desc = entry_priv->desc;69 skbdesc->desc_len = entry->queue->desc_size;70 71 /*72 * DMA is already done, notify rt2x00lib that73 * it finished successfully.74 */75 rt2x00lib_dmastart(entry);76 rt2x00lib_dmadone(entry);77 78 /*79 * Send the frame to rt2x00lib for further processing.80 */81 rt2x00lib_rxdone(entry, GFP_ATOMIC);82 }83 84 return !max_rx;85}86EXPORT_SYMBOL_GPL(rt2x00mmio_rxdone);87 88void rt2x00mmio_flush_queue(struct data_queue *queue, bool drop)89{90 unsigned int i;91 92 for (i = 0; !rt2x00queue_empty(queue) && i < 10; i++)93 msleep(50);94}95EXPORT_SYMBOL_GPL(rt2x00mmio_flush_queue);96 97/*98 * Device initialization handlers.99 */100static int rt2x00mmio_alloc_queue_dma(struct rt2x00_dev *rt2x00dev,101 struct data_queue *queue)102{103 struct queue_entry_priv_mmio *entry_priv;104 void *addr;105 dma_addr_t dma;106 unsigned int i;107 108 /*109 * Allocate DMA memory for descriptor and buffer.110 */111 addr = dma_alloc_coherent(rt2x00dev->dev,112 queue->limit * queue->desc_size, &dma,113 GFP_KERNEL);114 if (!addr)115 return -ENOMEM;116 117 /*118 * Initialize all queue entries to contain valid addresses.119 */120 for (i = 0; i < queue->limit; i++) {121 entry_priv = queue->entries[i].priv_data;122 entry_priv->desc = addr + i * queue->desc_size;123 entry_priv->desc_dma = dma + i * queue->desc_size;124 }125 126 return 0;127}128 129static void rt2x00mmio_free_queue_dma(struct rt2x00_dev *rt2x00dev,130 struct data_queue *queue)131{132 struct queue_entry_priv_mmio *entry_priv =133 queue->entries[0].priv_data;134 135 if (entry_priv->desc)136 dma_free_coherent(rt2x00dev->dev,137 queue->limit * queue->desc_size,138 entry_priv->desc, entry_priv->desc_dma);139 entry_priv->desc = NULL;140}141 142int rt2x00mmio_initialize(struct rt2x00_dev *rt2x00dev)143{144 struct data_queue *queue;145 int status;146 147 /*148 * Allocate DMA149 */150 queue_for_each(rt2x00dev, queue) {151 status = rt2x00mmio_alloc_queue_dma(rt2x00dev, queue);152 if (status)153 goto exit;154 }155 156 /*157 * Register interrupt handler.158 */159 status = request_irq(rt2x00dev->irq,160 rt2x00dev->ops->lib->irq_handler,161 IRQF_SHARED, rt2x00dev->name, rt2x00dev);162 if (status) {163 rt2x00_err(rt2x00dev, "IRQ %d allocation failed (error %d)\n",164 rt2x00dev->irq, status);165 goto exit;166 }167 168 return 0;169 170exit:171 queue_for_each(rt2x00dev, queue)172 rt2x00mmio_free_queue_dma(rt2x00dev, queue);173 174 return status;175}176EXPORT_SYMBOL_GPL(rt2x00mmio_initialize);177 178void rt2x00mmio_uninitialize(struct rt2x00_dev *rt2x00dev)179{180 struct data_queue *queue;181 182 /*183 * Free irq line.184 */185 free_irq(rt2x00dev->irq, rt2x00dev);186 187 /*188 * Free DMA189 */190 queue_for_each(rt2x00dev, queue)191 rt2x00mmio_free_queue_dma(rt2x00dev, queue);192}193EXPORT_SYMBOL_GPL(rt2x00mmio_uninitialize);194 195/*196 * rt2x00mmio module information.197 */198MODULE_AUTHOR(DRV_PROJECT);199MODULE_VERSION(DRV_VERSION);200MODULE_DESCRIPTION("rt2x00 mmio library");201MODULE_LICENSE("GPL");202