drivers/net/wimax/i2400m/sdio-rx.c - kernel/panda - Git at Google

 /*
  * 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);
 }
	/*
	* 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);
	}