diff options
Diffstat (limited to 'drivers/net/wimax/i2400m/sdio-rx.c')
| -rw-r--r-- | drivers/net/wimax/i2400m/sdio-rx.c | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/drivers/net/wimax/i2400m/sdio-rx.c b/drivers/net/wimax/i2400m/sdio-rx.c new file mode 100644 index 00000000..fb6396dd --- /dev/null +++ b/drivers/net/wimax/i2400m/sdio-rx.c @@ -0,0 +1,301 @@ +/* + * Intel Wireless WiMAX Connection 2400m + * SDIO RX handling + * + * + * Copyright (C) 2007-2008 Intel Corporation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * + * Intel Corporation <linux-wimax@intel.com> + * Dirk Brandewie <dirk.j.brandewie@intel.com> + * - Initial implementation + * + * + * This handles the RX path on SDIO. + * + * The SDIO bus driver calls the "irq" routine when data is available. + * This is not a traditional interrupt routine since the SDIO bus + * driver calls us from its irq thread context. Because of this + * sleeping in the SDIO RX IRQ routine is okay. + * + * From there on, we obtain the size of the data that is available, + * allocate an skb, copy it and then pass it to the generic driver's + * RX routine [i2400m_rx()]. + * + * ROADMAP + * + * i2400ms_irq() + * i2400ms_rx() + * __i2400ms_rx_get_size() + * i2400m_is_boot_barker() + * i2400m_rx() + * + * i2400ms_rx_setup() + * + * i2400ms_rx_release() + */ +#include <linux/workqueue.h> +#include <linux/wait.h> +#include <linux/skbuff.h> +#include <linux/mmc/sdio.h> +#include <linux/mmc/sdio_func.h> +#include <linux/slab.h> +#include "i2400m-sdio.h" + +#define D_SUBMODULE rx +#include "sdio-debug-levels.h" + +static const __le32 i2400m_ACK_BARKER[4] = { + __constant_cpu_to_le32(I2400M_ACK_BARKER), + __constant_cpu_to_le32(I2400M_ACK_BARKER), + __constant_cpu_to_le32(I2400M_ACK_BARKER), + __constant_cpu_to_le32(I2400M_ACK_BARKER) +}; + + +/* + * Read and return the amount of bytes available for RX + * + * The RX size has to be read like this: byte reads of three + * sequential locations; then glue'em together. + * + * sdio_readl() doesn't work. + */ +static ssize_t __i2400ms_rx_get_size(struct i2400ms *i2400ms) +{ + int ret, cnt, val; + ssize_t rx_size; + unsigned xfer_size_addr; + struct sdio_func *func = i2400ms->func; + struct device *dev = &i2400ms->func->dev; + + d_fnstart(7, dev, "(i2400ms %p)\n", i2400ms); + xfer_size_addr = I2400MS_INTR_GET_SIZE_ADDR; + rx_size = 0; + for (cnt = 0; cnt < 3; cnt++) { + val = sdio_readb(func, xfer_size_addr + cnt, &ret); + if (ret < 0) { + dev_err(dev, "RX: Can't read byte %d of RX size from " + "0x%08x: %d\n", cnt, xfer_size_addr + cnt, ret); + rx_size = ret; + goto error_read; + } + rx_size = rx_size << 8 | (val & 0xff); + } + d_printf(6, dev, "RX: rx_size is %ld\n", (long) rx_size); +error_read: + d_fnend(7, dev, "(i2400ms %p) = %ld\n", i2400ms, (long) rx_size); + return rx_size; +} + + +/* + * Read data from the device (when in normal) + * + * Allocate an SKB of the right size, read the data in and then + * deliver it to the generic layer. + * + * We also check for a reboot barker. That means the device died and + * we have to reboot it. + */ +static +void i2400ms_rx(struct i2400ms *i2400ms) +{ + int ret; + struct sdio_func *func = i2400ms->func; + struct device *dev = &func->dev; + struct i2400m *i2400m = &i2400ms->i2400m; + struct sk_buff *skb; + ssize_t rx_size; + + d_fnstart(7, dev, "(i2400ms %p)\n", i2400ms); + rx_size = __i2400ms_rx_get_size(i2400ms); + if (rx_size < 0) { + ret = rx_size; + goto error_get_size; + } + /* + * Hardware quirk: make sure to clear the INTR status register + * AFTER getting the data transfer size. + */ + sdio_writeb(func, 1, I2400MS_INTR_CLEAR_ADDR, &ret); + + ret = -ENOMEM; + skb = alloc_skb(rx_size, GFP_ATOMIC); + if (NULL == skb) { + dev_err(dev, "RX: unable to alloc skb\n"); + goto error_alloc_skb; + } + ret = sdio_memcpy_fromio(func, skb->data, + I2400MS_DATA_ADDR, rx_size); + if (ret < 0) { + dev_err(dev, "RX: SDIO data read failed: %d\n", ret); + goto error_memcpy_fromio; + } + + rmb(); /* make sure we get boot_mode from dev_reset_handle */ + if (unlikely(i2400m->boot_mode == 1)) { + spin_lock(&i2400m->rx_lock); + i2400ms->bm_ack_size = rx_size; + spin_unlock(&i2400m->rx_lock); + memcpy(i2400m->bm_ack_buf, skb->data, rx_size); + wake_up(&i2400ms->bm_wfa_wq); + d_printf(5, dev, "RX: SDIO boot mode message\n"); + kfree_skb(skb); + goto out; + } + ret = -EIO; + if (unlikely(rx_size < sizeof(__le32))) { + dev_err(dev, "HW BUG? only %zu bytes received\n", rx_size); + goto error_bad_size; + } + if (likely(i2400m_is_d2h_barker(skb->data))) { + skb_put(skb, rx_size); + i2400m_rx(i2400m, skb); + } else if (unlikely(i2400m_is_boot_barker(i2400m, + skb->data, rx_size))) { + ret = i2400m_dev_reset_handle(i2400m, "device rebooted"); + dev_err(dev, "RX: SDIO reboot barker\n"); + kfree_skb(skb); + } else { + i2400m_unknown_barker(i2400m, skb->data, rx_size); + kfree_skb(skb); + } +out: + d_fnend(7, dev, "(i2400ms %p) = void\n", i2400ms); + return; + +error_memcpy_fromio: + kfree_skb(skb); +error_alloc_skb: +error_get_size: +error_bad_size: + d_fnend(7, dev, "(i2400ms %p) = %d\n", i2400ms, ret); +} + + +/* + * Process an interrupt from the SDIO card + * + * FIXME: need to process other events that are not just ready-to-read + * + * Checks there is data ready and then proceeds to read it. + */ +static +void i2400ms_irq(struct sdio_func *func) +{ + int ret; + struct i2400ms *i2400ms = sdio_get_drvdata(func); + struct device *dev = &func->dev; + int val; + + d_fnstart(6, dev, "(i2400ms %p)\n", i2400ms); + val = sdio_readb(func, I2400MS_INTR_STATUS_ADDR, &ret); + if (ret < 0) { + dev_err(dev, "RX: Can't read interrupt status: %d\n", ret); + goto error_no_irq; + } + if (!val) { + dev_err(dev, "RX: BUG? got IRQ but no interrupt ready?\n"); + goto error_no_irq; + } + i2400ms_rx(i2400ms); +error_no_irq: + d_fnend(6, dev, "(i2400ms %p) = void\n", i2400ms); +} + + +/* + * Setup SDIO RX + * + * Hooks up the IRQ handler and then enables IRQs. + */ +int i2400ms_rx_setup(struct i2400ms *i2400ms) +{ + int result; + struct sdio_func *func = i2400ms->func; + struct device *dev = &func->dev; + struct i2400m *i2400m = &i2400ms->i2400m; + + d_fnstart(5, dev, "(i2400ms %p)\n", i2400ms); + + init_waitqueue_head(&i2400ms->bm_wfa_wq); + spin_lock(&i2400m->rx_lock); + i2400ms->bm_wait_result = -EINPROGRESS; + /* + * Before we are about to enable the RX interrupt, make sure + * bm_ack_size is cleared to -EINPROGRESS which indicates + * no RX interrupt happened yet or the previous interrupt + * has been handled, we are ready to take the new interrupt + */ + i2400ms->bm_ack_size = -EINPROGRESS; + spin_unlock(&i2400m->rx_lock); + + sdio_claim_host(func); + result = sdio_claim_irq(func, i2400ms_irq); + if (result < 0) { + dev_err(dev, "Cannot claim IRQ: %d\n", result); + goto error_irq_claim; + } + result = 0; + sdio_writeb(func, 1, I2400MS_INTR_ENABLE_ADDR, &result); + if (result < 0) { + sdio_release_irq(func); + dev_err(dev, "Failed to enable interrupts %d\n", result); + } +error_irq_claim: + sdio_release_host(func); + d_fnend(5, dev, "(i2400ms %p) = %d\n", i2400ms, result); + return result; +} + + +/* + * Tear down SDIO RX + * + * Disables IRQs in the device and removes the IRQ handler. + */ +void i2400ms_rx_release(struct i2400ms *i2400ms) +{ + int result; + struct sdio_func *func = i2400ms->func; + struct device *dev = &func->dev; + struct i2400m *i2400m = &i2400ms->i2400m; + + d_fnstart(5, dev, "(i2400ms %p)\n", i2400ms); + spin_lock(&i2400m->rx_lock); + i2400ms->bm_ack_size = -EINTR; + spin_unlock(&i2400m->rx_lock); + wake_up_all(&i2400ms->bm_wfa_wq); + sdio_claim_host(func); + sdio_writeb(func, 0, I2400MS_INTR_ENABLE_ADDR, &result); + sdio_release_irq(func); + sdio_release_host(func); + d_fnend(5, dev, "(i2400ms %p) = %d\n", i2400ms, result); +} |