rt2x00: rt2x00pci: fix build error on Ralink RT3x5x SoCs

The rt2800pci driver supports the built-in wireless
MAC of the Ralink RT3x5x SoCs. However building the
driver for these SoCs leads to the following error:

    LD      init/built-in.o
  drivers/built-in.o: In function `rt2800pci_rxdone_tasklet':
  <...>/drivers/net/wireless/rt2x00/rt2800pci.c:1012: undefined reference to `rt2x00pci_rxdone'
  drivers/built-in.o:(.rodata+0x4780): undefined reference to `rt2x00pci_initialize'
  drivers/built-in.o:(.rodata+0x4784): undefined reference to `rt2x00pci_uninitialize'
  drivers/built-in.o:(.rodata+0x47bc): undefined reference to `rt2x00pci_flush_queue'
  drivers/built-in.o:(.rodata+0x4818): undefined reference to `rt2x00pci_regbusy_read'
  make[5]: *** [vmlinux] Error 1

The missing functions are provided by the rt2x00pci
module. This module is only selected by the rt2800pci
driver if PCI support is enabled in the kernel, because
some parts of the rt2x00pci code depends on PCI support.

PCI support is not available on the RT3x5x SoCs because
those have no PCI host controller at all.

Move the non PCI specific code from rt2x00pci into a
separate module. This makes it possible to use that
code even if PCI support is disabled. The affected
functions are used by all of the rt2x00 PCI drivers
so select the new module for those drivers.

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/Kconfig

@@ -20,6 +20,7 @@ if RT2X00
 config RT2400PCI
 	tristate "Ralink rt2400 (PCI/PCMCIA) support"
 	depends on PCI
+	select RT2X00_LIB_MMIO
 	select RT2X00_LIB_PCI
 	select EEPROM_93CX6
 	---help---
@@ -31,6 +32,7 @@ config RT2400PCI
 config RT2500PCI
 	tristate "Ralink rt2500 (PCI/PCMCIA) support"
 	depends on PCI
+	select RT2X00_LIB_MMIO
 	select RT2X00_LIB_PCI
 	select EEPROM_93CX6
 	---help---
@@ -43,6 +45,7 @@ config RT61PCI
 	tristate "Ralink rt2501/rt61 (PCI/PCMCIA) support"
 	depends on PCI
 	select RT2X00_LIB_PCI
+	select RT2X00_LIB_MMIO
 	select RT2X00_LIB_FIRMWARE
 	select RT2X00_LIB_CRYPTO
 	select CRC_ITU_T
@@ -57,6 +60,7 @@ config RT2800PCI
 	tristate "Ralink rt27xx/rt28xx/rt30xx (PCI/PCIe/PCMCIA) support"
 	depends on PCI || SOC_RT288X || SOC_RT305X
 	select RT2800_LIB
+	select RT2X00_LIB_MMIO
 	select RT2X00_LIB_PCI if PCI
 	select RT2X00_LIB_SOC if SOC_RT288X || SOC_RT305X
 	select RT2X00_LIB_FIRMWARE
@@ -185,6 +189,9 @@ endif
 config RT2800_LIB
 	tristate
 
+config RT2X00_LIB_MMIO
+	tristate
+
 config RT2X00_LIB_PCI
 	tristate
 	select RT2X00_LIB

drivers/net/wireless/rt2x00/Makefile

@@ -9,6 +9,7 @@ rt2x00lib-$(CONFIG_RT2X00_LIB_FIRMWARE)	+= rt2x00firmware.o
 rt2x00lib-$(CONFIG_RT2X00_LIB_LEDS)	+= rt2x00leds.o
 
 obj-$(CONFIG_RT2X00_LIB)		+= rt2x00lib.o
+obj-$(CONFIG_RT2X00_LIB_MMIO)		+= rt2x00mmio.o
 obj-$(CONFIG_RT2X00_LIB_PCI)		+= rt2x00pci.o
 obj-$(CONFIG_RT2X00_LIB_SOC)		+= rt2x00soc.o
 obj-$(CONFIG_RT2X00_LIB_USB)		+= rt2x00usb.o

drivers/net/wireless/rt2x00/rt2400pci.c

@@ -34,6 +34,7 @@
 #include <linux/slab.h>
 
 #include "rt2x00.h"
+#include "rt2x00mmio.h"
 #include "rt2x00pci.h"
 #include "rt2400pci.h"
 

drivers/net/wireless/rt2x00/rt2500pci.c

@@ -34,6 +34,7 @@
 #include <linux/slab.h>
 
 #include "rt2x00.h"
+#include "rt2x00mmio.h"
 #include "rt2x00pci.h"
 #include "rt2500pci.h"
 

drivers/net/wireless/rt2x00/rt2800pci.c

@@ -41,6 +41,7 @@
 #include <linux/eeprom_93cx6.h>
 
 #include "rt2x00.h"
+#include "rt2x00mmio.h"
 #include "rt2x00pci.h"
 #include "rt2x00soc.h"
 #include "rt2800lib.h"

drivers/net/wireless/rt2x00/rt2x00mmio.c

@@ -0,0 +1,216 @@
+/*
+	Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com>
+	<http://rt2x00.serialmonkey.com>
+
+	This program is free software; you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation; either version 2 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to the
+	Free Software Foundation, Inc.,
+	59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+/*
+	Module: rt2x00mmio
+	Abstract: rt2x00 generic mmio device routines.
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "rt2x00.h"
+#include "rt2x00mmio.h"
+
+/*
+ * Register access.
+ */
+int rt2x00pci_regbusy_read(struct rt2x00_dev *rt2x00dev,
+			   const unsigned int offset,
+			   const struct rt2x00_field32 field,
+			   u32 *reg)
+{
+	unsigned int i;
+
+	if (!test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
+		return 0;
+
+	for (i = 0; i < REGISTER_BUSY_COUNT; i++) {
+		rt2x00pci_register_read(rt2x00dev, offset, reg);
+		if (!rt2x00_get_field32(*reg, field))
+			return 1;
+		udelay(REGISTER_BUSY_DELAY);
+	}
+
+	printk_once(KERN_ERR "%s() Indirect register access failed: "
+	      "offset=0x%.08x, value=0x%.08x\n", __func__, offset, *reg);
+	*reg = ~0;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rt2x00pci_regbusy_read);
+
+bool rt2x00pci_rxdone(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_queue *queue = rt2x00dev->rx;
+	struct queue_entry *entry;
+	struct queue_entry_priv_pci *entry_priv;
+	struct skb_frame_desc *skbdesc;
+	int max_rx = 16;
+
+	while (--max_rx) {
+		entry = rt2x00queue_get_entry(queue, Q_INDEX);
+		entry_priv = entry->priv_data;
+
+		if (rt2x00dev->ops->lib->get_entry_state(entry))
+			break;
+
+		/*
+		 * Fill in desc fields of the skb descriptor
+		 */
+		skbdesc = get_skb_frame_desc(entry->skb);
+		skbdesc->desc = entry_priv->desc;
+		skbdesc->desc_len = entry->queue->desc_size;
+
+		/*
+		 * DMA is already done, notify rt2x00lib that
+		 * it finished successfully.
+		 */
+		rt2x00lib_dmastart(entry);
+		rt2x00lib_dmadone(entry);
+
+		/*
+		 * Send the frame to rt2x00lib for further processing.
+		 */
+		rt2x00lib_rxdone(entry, GFP_ATOMIC);
+	}
+
+	return !max_rx;
+}
+EXPORT_SYMBOL_GPL(rt2x00pci_rxdone);
+
+void rt2x00pci_flush_queue(struct data_queue *queue, bool drop)
+{
+	unsigned int i;
+
+	for (i = 0; !rt2x00queue_empty(queue) && i < 10; i++)
+		msleep(10);
+}
+EXPORT_SYMBOL_GPL(rt2x00pci_flush_queue);
+
+/*
+ * Device initialization handlers.
+ */
+static int rt2x00pci_alloc_queue_dma(struct rt2x00_dev *rt2x00dev,
+				     struct data_queue *queue)
+{
+	struct queue_entry_priv_pci *entry_priv;
+	void *addr;
+	dma_addr_t dma;
+	unsigned int i;
+
+	/*
+	 * Allocate DMA memory for descriptor and buffer.
+	 */
+	addr = dma_alloc_coherent(rt2x00dev->dev,
+				  queue->limit * queue->desc_size,
+				  &dma, GFP_KERNEL);
+	if (!addr)
+		return -ENOMEM;
+
+	memset(addr, 0, queue->limit * queue->desc_size);
+
+	/*
+	 * Initialize all queue entries to contain valid addresses.
+	 */
+	for (i = 0; i < queue->limit; i++) {
+		entry_priv = queue->entries[i].priv_data;
+		entry_priv->desc = addr + i * queue->desc_size;
+		entry_priv->desc_dma = dma + i * queue->desc_size;
+	}
+
+	return 0;
+}
+
+static void rt2x00pci_free_queue_dma(struct rt2x00_dev *rt2x00dev,
+				     struct data_queue *queue)
+{
+	struct queue_entry_priv_pci *entry_priv =
+	    queue->entries[0].priv_data;
+
+	if (entry_priv->desc)
+		dma_free_coherent(rt2x00dev->dev,
+				  queue->limit * queue->desc_size,
+				  entry_priv->desc, entry_priv->desc_dma);
+	entry_priv->desc = NULL;
+}
+
+int rt2x00pci_initialize(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_queue *queue;
+	int status;
+
+	/*
+	 * Allocate DMA
+	 */
+	queue_for_each(rt2x00dev, queue) {
+		status = rt2x00pci_alloc_queue_dma(rt2x00dev, queue);
+		if (status)
+			goto exit;
+	}
+
+	/*
+	 * Register interrupt handler.
+	 */
+	status = request_irq(rt2x00dev->irq,
+			     rt2x00dev->ops->lib->irq_handler,
+			     IRQF_SHARED, rt2x00dev->name, rt2x00dev);
+	if (status) {
+		ERROR(rt2x00dev, "IRQ %d allocation failed (error %d).\n",
+		      rt2x00dev->irq, status);
+		goto exit;
+	}
+
+	return 0;
+
+exit:
+	queue_for_each(rt2x00dev, queue)
+		rt2x00pci_free_queue_dma(rt2x00dev, queue);
+
+	return status;
+}
+EXPORT_SYMBOL_GPL(rt2x00pci_initialize);
+
+void rt2x00pci_uninitialize(struct rt2x00_dev *rt2x00dev)
+{
+	struct data_queue *queue;
+
+	/*
+	 * Free irq line.
+	 */
+	free_irq(rt2x00dev->irq, rt2x00dev);
+
+	/*
+	 * Free DMA
+	 */
+	queue_for_each(rt2x00dev, queue)
+		rt2x00pci_free_queue_dma(rt2x00dev, queue);
+}
+EXPORT_SYMBOL_GPL(rt2x00pci_uninitialize);
+
+/*
+ * rt2x00mmio module information.
+ */
+MODULE_AUTHOR(DRV_PROJECT);
+MODULE_VERSION(DRV_VERSION);
+MODULE_DESCRIPTION("rt2x00 mmio library");
+MODULE_LICENSE("GPL");