1/* 2 * Intel Wireless WiMAX Connection 2400m 3 * SDIO RX handling 4 * 5 * 6 * Copyright (C) 2007-2008 Intel Corporation. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * * Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * * Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in 16 * the documentation and/or other materials provided with the 17 * distribution. 18 * * Neither the name of Intel Corporation nor the names of its 19 * contributors may be used to endorse or promote products derived 20 * from this software without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 25 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 26 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 28 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 32 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 * 34 * 35 * Intel Corporation <linux-wimax@intel.com> 36 * Dirk Brandewie <dirk.j.brandewie@intel.com> 37 * - Initial implementation 38 * 39 * 40 * This handles the RX path on SDIO. 41 * 42 * The SDIO bus driver calls the "irq" routine when data is available. 43 * This is not a traditional interrupt routine since the SDIO bus 44 * driver calls us from its irq thread context. Because of this 45 * sleeping in the SDIO RX IRQ routine is okay. 46 * 47 * From there on, we obtain the size of the data that is available, 48 * allocate an skb, copy it and then pass it to the generic driver's 49 * RX routine [i2400m_rx()]. 50 * 51 * ROADMAP 52 * 53 * i2400ms_irq() 54 * i2400ms_rx() 55 * __i2400ms_rx_get_size() 56 * i2400m_is_boot_barker() 57 * i2400m_rx() 58 * 59 * i2400ms_rx_setup() 60 * 61 * i2400ms_rx_release() 62 */ 63#include <linux/workqueue.h> 64#include <linux/wait.h> 65#include <linux/skbuff.h> 66#include <linux/mmc/sdio.h> 67#include <linux/mmc/sdio_func.h> 68#include <linux/slab.h> 69#include "i2400m-sdio.h" 70 71#define D_SUBMODULE rx 72#include "sdio-debug-levels.h" 73 74static const __le32 i2400m_ACK_BARKER[4] = { 75 __constant_cpu_to_le32(I2400M_ACK_BARKER), 76 __constant_cpu_to_le32(I2400M_ACK_BARKER), 77 __constant_cpu_to_le32(I2400M_ACK_BARKER), 78 __constant_cpu_to_le32(I2400M_ACK_BARKER) 79}; 80 81 82/* 83 * Read and return the amount of bytes available for RX 84 * 85 * The RX size has to be read like this: byte reads of three 86 * sequential locations; then glue'em together. 87 * 88 * sdio_readl() doesn't work. 89 */ 90ssize_t __i2400ms_rx_get_size(struct i2400ms *i2400ms) 91{ 92 int ret, cnt, val; 93 ssize_t rx_size; 94 unsigned xfer_size_addr; 95 struct sdio_func *func = i2400ms->func; 96 struct device *dev = &i2400ms->func->dev; 97 98 d_fnstart(7, dev, "(i2400ms %p)\n", i2400ms); 99 xfer_size_addr = I2400MS_INTR_GET_SIZE_ADDR; 100 rx_size = 0; 101 for (cnt = 0; cnt < 3; cnt++) { 102 val = sdio_readb(func, xfer_size_addr + cnt, &ret); 103 if (ret < 0) { 104 dev_err(dev, "RX: Can't read byte %d of RX size from " 105 "0x%08x: %d\n", cnt, xfer_size_addr + cnt, ret); 106 rx_size = ret; 107 goto error_read; 108 } 109 rx_size = rx_size << 8 | (val & 0xff); 110 } 111 d_printf(6, dev, "RX: rx_size is %ld\n", (long) rx_size); 112error_read: 113 d_fnend(7, dev, "(i2400ms %p) = %ld\n", i2400ms, (long) rx_size); 114 return rx_size; 115} 116 117 118/* 119 * Read data from the device (when in normal) 120 * 121 * Allocate an SKB of the right size, read the data in and then 122 * deliver it to the generic layer. 123 * 124 * We also check for a reboot barker. That means the device died and 125 * we have to reboot it. 126 */ 127static 128void i2400ms_rx(struct i2400ms *i2400ms) 129{ 130 int ret; 131 struct sdio_func *func = i2400ms->func; 132 struct device *dev = &func->dev; 133 struct i2400m *i2400m = &i2400ms->i2400m; 134 struct sk_buff *skb; 135 ssize_t rx_size; 136 137 d_fnstart(7, dev, "(i2400ms %p)\n", i2400ms); 138 rx_size = __i2400ms_rx_get_size(i2400ms); 139 if (rx_size < 0) { 140 ret = rx_size; 141 goto error_get_size; 142 } 143 /* 144 * Hardware quirk: make sure to clear the INTR status register 145 * AFTER getting the data transfer size. 146 */ 147 sdio_writeb(func, 1, I2400MS_INTR_CLEAR_ADDR, &ret); 148 149 ret = -ENOMEM; 150 skb = alloc_skb(rx_size, GFP_ATOMIC); 151 if (NULL == skb) { 152 dev_err(dev, "RX: unable to alloc skb\n"); 153 goto error_alloc_skb; 154 } 155 ret = sdio_memcpy_fromio(func, skb->data, 156 I2400MS_DATA_ADDR, rx_size); 157 if (ret < 0) { 158 dev_err(dev, "RX: SDIO data read failed: %d\n", ret); 159 goto error_memcpy_fromio; 160 } 161 162 rmb(); /* make sure we get boot_mode from dev_reset_handle */ 163 if (unlikely(i2400m->boot_mode == 1)) { 164 spin_lock(&i2400m->rx_lock); 165 i2400ms->bm_ack_size = rx_size; 166 spin_unlock(&i2400m->rx_lock); 167 memcpy(i2400m->bm_ack_buf, skb->data, rx_size); 168 wake_up(&i2400ms->bm_wfa_wq); 169 d_printf(5, dev, "RX: SDIO boot mode message\n"); 170 kfree_skb(skb); 171 goto out; 172 } 173 ret = -EIO; 174 if (unlikely(rx_size < sizeof(__le32))) { 175 dev_err(dev, "HW BUG? only %zu bytes received\n", rx_size); 176 goto error_bad_size; 177 } 178 if (likely(i2400m_is_d2h_barker(skb->data))) { 179 skb_put(skb, rx_size); 180 i2400m_rx(i2400m, skb); 181 } else if (unlikely(i2400m_is_boot_barker(i2400m, 182 skb->data, rx_size))) { 183 ret = i2400m_dev_reset_handle(i2400m, "device rebooted"); 184 dev_err(dev, "RX: SDIO reboot barker\n"); 185 kfree_skb(skb); 186 } else { 187 i2400m_unknown_barker(i2400m, skb->data, rx_size); 188 kfree_skb(skb); 189 } 190out: 191 d_fnend(7, dev, "(i2400ms %p) = void\n", i2400ms); 192 return; 193 194error_memcpy_fromio: 195 kfree_skb(skb); 196error_alloc_skb: 197error_get_size: 198error_bad_size: 199 d_fnend(7, dev, "(i2400ms %p) = %d\n", i2400ms, ret); 200} 201 202 203static 204void i2400ms_irq(struct sdio_func *func) 205{ 206 int ret; 207 struct i2400ms *i2400ms = sdio_get_drvdata(func); 208 struct device *dev = &func->dev; 209 int val; 210 211 d_fnstart(6, dev, "(i2400ms %p)\n", i2400ms); 212 val = sdio_readb(func, I2400MS_INTR_STATUS_ADDR, &ret); 213 if (ret < 0) { 214 dev_err(dev, "RX: Can't read interrupt status: %d\n", ret); 215 goto error_no_irq; 216 } 217 if (!val) { 218 dev_err(dev, "RX: BUG? got IRQ but no interrupt ready?\n"); 219 goto error_no_irq; 220 } 221 i2400ms_rx(i2400ms); 222error_no_irq: 223 d_fnend(6, dev, "(i2400ms %p) = void\n", i2400ms); 224} 225 226 227/* 228 * Setup SDIO RX 229 * 230 * Hooks up the IRQ handler and then enables IRQs. 231 */ 232int i2400ms_rx_setup(struct i2400ms *i2400ms) 233{ 234 int result; 235 struct sdio_func *func = i2400ms->func; 236 struct device *dev = &func->dev; 237 struct i2400m *i2400m = &i2400ms->i2400m; 238 239 d_fnstart(5, dev, "(i2400ms %p)\n", i2400ms); 240 241 init_waitqueue_head(&i2400ms->bm_wfa_wq); 242 spin_lock(&i2400m->rx_lock); 243 i2400ms->bm_wait_result = -EINPROGRESS; 244 /* 245 * Before we are about to enable the RX interrupt, make sure 246 * bm_ack_size is cleared to -EINPROGRESS which indicates 247 * no RX interrupt happened yet or the previous interrupt 248 * has been handled, we are ready to take the new interrupt 249 */ 250 i2400ms->bm_ack_size = -EINPROGRESS; 251 spin_unlock(&i2400m->rx_lock); 252 253 sdio_claim_host(func); 254 result = sdio_claim_irq(func, i2400ms_irq); 255 if (result < 0) { 256 dev_err(dev, "Cannot claim IRQ: %d\n", result); 257 goto error_irq_claim; 258 } 259 result = 0; 260 sdio_writeb(func, 1, I2400MS_INTR_ENABLE_ADDR, &result); 261 if (result < 0) { 262 sdio_release_irq(func); 263 dev_err(dev, "Failed to enable interrupts %d\n", result); 264 } 265error_irq_claim: 266 sdio_release_host(func); 267 d_fnend(5, dev, "(i2400ms %p) = %d\n", i2400ms, result); 268 return result; 269} 270 271 272/* 273 * Tear down SDIO RX 274 * 275 * Disables IRQs in the device and removes the IRQ handler. 276 */ 277void i2400ms_rx_release(struct i2400ms *i2400ms) 278{ 279 int result; 280 struct sdio_func *func = i2400ms->func; 281 struct device *dev = &func->dev; 282 struct i2400m *i2400m = &i2400ms->i2400m; 283 284 d_fnstart(5, dev, "(i2400ms %p)\n", i2400ms); 285 spin_lock(&i2400m->rx_lock); 286 i2400ms->bm_ack_size = -EINTR; 287 spin_unlock(&i2400m->rx_lock); 288 wake_up_all(&i2400ms->bm_wfa_wq); 289 sdio_claim_host(func); 290 sdio_writeb(func, 0, I2400MS_INTR_ENABLE_ADDR, &result); 291 sdio_release_irq(func); 292 sdio_release_host(func); 293 d_fnend(5, dev, "(i2400ms %p) = %d\n", i2400ms, result); 294} 295