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authorblogic <blogic@3c298f89-4303-0410-b956-a3cf2f4a3e73>2012-10-05 10:12:53 +0000
committerblogic <blogic@3c298f89-4303-0410-b956-a3cf2f4a3e73>2012-10-05 10:12:53 +0000
commit5c105d9f3fd086aff195d3849dcf847d6b0bd927 (patch)
tree1229a11f725bfa58aa7c57a76898553bb5f6654a /target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c
downloadopenwrt-5c105d9f3fd086aff195d3849dcf847d6b0bd927.tar.gz
openwrt-5c105d9f3fd086aff195d3849dcf847d6b0bd927.zip
branch Attitude Adjustment
git-svn-id: svn://svn.openwrt.org/openwrt/branches/attitude_adjustment@33625 3c298f89-4303-0410-b956-a3cf2f4a3e73
Diffstat (limited to 'target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c')
-rw-r--r--target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c288
1 files changed, 288 insertions, 0 deletions
diff --git a/target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c b/target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c
new file mode 100644
index 000000000..654ac4ced
--- /dev/null
+++ b/target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c
@@ -0,0 +1,288 @@
+/*
+ * drivers/uio/uio_ubicom32ring.c
+ *
+ * Userspace I/O platform driver for Ubicom32 ring buffers
+ *
+ * (C) Copyright 2009, Ubicom, Inc.
+ *
+ * This file is part of the Ubicom32 Linux Kernel Port.
+ *
+ * Based on uio_ubicom32ring.c by Magnus Damm
+ *
+ * The Ubicom32 Linux Kernel Port 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.
+ *
+ * The Ubicom32 Linux Kernel Port 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 the Ubicom32 Linux Kernel Port. If not,
+ * see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/uio_driver.h>
+#include <linux/spinlock.h>
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/stringify.h>
+
+#include <asm/ip5000.h>
+#include <asm/ubicom32ring.h>
+
+#define DRIVER_NAME "uio_ubicom32ring"
+
+struct uio_ubicom32ring_data {
+ struct uio_info *uioinfo;
+
+ struct uio_ubicom32ring_regs *regs;
+
+ /*
+ * IRQ used to kick the ring buffer
+ */
+ int irq_tx;
+ int irq_rx;
+
+ spinlock_t lock;
+
+ unsigned long flags;
+
+ char name[0];
+};
+
+static irqreturn_t uio_ubicom32ring_handler(int irq, struct uio_info *dev_info)
+{
+ struct uio_ubicom32ring_data *priv = dev_info->priv;
+
+ /* Just disable the interrupt in the interrupt controller, and
+ * remember the state so we can allow user space to enable it later.
+ */
+
+ if (!test_and_set_bit(0, &priv->flags))
+ disable_irq_nosync(irq);
+
+ return IRQ_HANDLED;
+}
+
+static int uio_ubicom32ring_irqcontrol(struct uio_info *dev_info, s32 irq_on)
+{
+ struct uio_ubicom32ring_data *priv = dev_info->priv;
+ unsigned long flags;
+
+ /* Allow user space to enable and disable the interrupt
+ * in the interrupt controller, but keep track of the
+ * state to prevent per-irq depth damage.
+ *
+ * Serialize this operation to support multiple tasks.
+ */
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ if (irq_on & 2) {
+ /*
+ * Kick the ring buffer (if we can)
+ */
+ if (priv->irq_tx != 0xFF) {
+ ubicom32_set_interrupt(priv->irq_tx);
+ }
+ }
+
+ if (priv->irq_rx != 0xFF) {
+ if (irq_on & 1) {
+ if (test_and_clear_bit(0, &priv->flags))
+ enable_irq(dev_info->irq);
+ } else {
+ if (!test_and_set_bit(0, &priv->flags))
+ disable_irq(dev_info->irq);
+ }
+ }
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int uio_ubicom32ring_probe(struct platform_device *pdev)
+{
+ struct uio_info *uioinfo;
+ struct uio_mem *uiomem;
+ struct uio_ubicom32ring_data *priv;
+ struct uio_ubicom32ring_regs *regs;
+ struct resource *mem_resource;
+ struct resource *irqtx_resource;
+ struct resource *irqrx_resource;
+ int ret = -EINVAL;
+ int i;
+
+ uioinfo = kzalloc(sizeof(struct uio_info), GFP_KERNEL);
+ if (!uioinfo) {
+ dev_err(&pdev->dev, "unable to kmalloc\n");
+ return -ENOMEM;
+ }
+
+ /*
+ * Allocate private data with some string space after
+ */
+ i = sizeof(DRIVER_NAME) + 1;
+ i += pdev->dev.platform_data ? strlen(pdev->dev.platform_data) : 0;
+ priv = kzalloc(sizeof(struct uio_ubicom32ring_data) + i, GFP_KERNEL);
+ if (!priv) {
+ dev_err(&pdev->dev, "unable to kmalloc\n");
+ kfree(uioinfo);
+ return -ENOMEM;
+ }
+
+ strcpy(priv->name, DRIVER_NAME ":");
+ if (pdev->dev.platform_data) {
+ strcat(priv->name, pdev->dev.platform_data);
+ }
+ uioinfo->priv = priv;
+ uioinfo->name = priv->name;
+ uioinfo->version = "0.1";
+
+ priv->uioinfo = uioinfo;
+ spin_lock_init(&priv->lock);
+ priv->flags = 0; /* interrupt is enabled to begin with */
+
+ /*
+ * Get our resources, the IRQ_TX and IRQ_RX are optional.
+ */
+ priv->irq_tx = 0xFF;
+ irqtx_resource = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (irqtx_resource) {
+ priv->irq_tx = irqtx_resource->start;
+ }
+
+ uioinfo->irq = -1;
+ priv->irq_rx = 0xFF;
+ irqrx_resource = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
+ if (irqrx_resource) {
+ priv->irq_rx = irqrx_resource->start;
+ uioinfo->irq = priv->irq_rx;
+ uioinfo->handler = uio_ubicom32ring_handler;
+ }
+
+ mem_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!mem_resource || !mem_resource->start) {
+ dev_err(&pdev->dev, "No valid memory resource found\n");
+ ret = -ENODEV;
+ goto fail;
+ }
+ regs = (struct uio_ubicom32ring_regs *)mem_resource->start;
+ priv->regs = regs;
+
+ if (regs->version != UIO_UBICOM32RING_REG_VERSION) {
+ dev_err(&pdev->dev, "version %d not supported\n", regs->version);
+ ret = -ENODEV;
+ goto fail;
+ }
+
+ /*
+ * First range is the shared register space, if we have any
+ */
+ uiomem = &uioinfo->mem[0];
+ if (regs->regs_size) {
+ uiomem->memtype = UIO_MEM_PHYS;
+ uiomem->addr = (u32_t)regs->regs;
+ uiomem->size = regs->regs_size;
+ ++uiomem;
+ dev_info(&pdev->dev, "regs:%p (%u) / rings: %d found\n", regs->regs, regs->regs_size, regs->num_rings);
+ } else {
+ dev_info(&pdev->dev, "rings: %d found\n", regs->num_rings);
+ }
+
+ /*
+ * The rest of the range correspond to the rings
+ */
+ for (i = 0; i < regs->num_rings; i++) {
+ dev_info(&pdev->dev, "\t%d: entries:%d ring:%p\n",
+ i, regs->rings[i]->entries, &(regs->rings[i]->ring));
+ if (uiomem >= &uioinfo->mem[MAX_UIO_MAPS]) {
+ dev_warn(&pdev->dev, "device has more than "
+ __stringify(MAX_UIO_MAPS)
+ " I/O memory resources.\n");
+ break;
+ }
+
+ uiomem->memtype = UIO_MEM_PHYS;
+ uiomem->addr = (u32_t)&(regs->rings[i]->head);
+ uiomem->size = (regs->rings[i]->entries * sizeof(u32_t)) +
+ sizeof(struct uio_ubicom32ring_desc);
+ ++uiomem;
+ }
+
+ while (uiomem < &uioinfo->mem[MAX_UIO_MAPS]) {
+ uiomem->size = 0;
+ ++uiomem;
+ }
+
+ /* This driver requires no hardware specific kernel code to handle
+ * interrupts. Instead, the interrupt handler simply disables the
+ * interrupt in the interrupt controller. User space is responsible
+ * for performing hardware specific acknowledge and re-enabling of
+ * the interrupt in the interrupt controller.
+ *
+ * Interrupt sharing is not supported.
+ */
+ uioinfo->irq_flags = IRQF_DISABLED;
+ uioinfo->irqcontrol = uio_ubicom32ring_irqcontrol;
+
+ ret = uio_register_device(&pdev->dev, priv->uioinfo);
+ if (ret) {
+ dev_err(&pdev->dev, "unable to register uio device\n");
+ goto fail;
+ }
+
+ platform_set_drvdata(pdev, priv);
+
+ dev_info(&pdev->dev, "'%s' using irq: rx %d tx %d, regs %p\n",
+ priv->name, priv->irq_rx, priv->irq_tx, priv->regs);
+
+ return 0;
+
+fail:
+ kfree(uioinfo);
+ kfree(priv);
+ return ret;
+}
+
+static int uio_ubicom32ring_remove(struct platform_device *pdev)
+{
+ struct uio_ubicom32ring_data *priv = platform_get_drvdata(pdev);
+
+ uio_unregister_device(priv->uioinfo);
+ kfree(priv->uioinfo);
+ kfree(priv);
+ return 0;
+}
+
+static struct platform_driver uio_ubicom32ring = {
+ .probe = uio_ubicom32ring_probe,
+ .remove = uio_ubicom32ring_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init uio_ubicom32ring_init(void)
+{
+ return platform_driver_register(&uio_ubicom32ring);
+}
+
+static void __exit uio_ubicom32ring_exit(void)
+{
+ platform_driver_unregister(&uio_ubicom32ring);
+}
+
+module_init(uio_ubicom32ring_init);
+module_exit(uio_ubicom32ring_exit);
+
+MODULE_AUTHOR("Patrick Tjin");
+MODULE_DESCRIPTION("Userspace I/O driver for Ubicom32 ring buffers");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRIVER_NAME);