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author | blogic <blogic@3c298f89-4303-0410-b956-a3cf2f4a3e73> | 2012-10-05 10:12:53 +0000 |
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committer | blogic <blogic@3c298f89-4303-0410-b956-a3cf2f4a3e73> | 2012-10-05 10:12:53 +0000 |
commit | 5c105d9f3fd086aff195d3849dcf847d6b0bd927 (patch) | |
tree | 1229a11f725bfa58aa7c57a76898553bb5f6654a /target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c | |
download | openwrt-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.c | 288 |
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); |