diff options
Diffstat (limited to 'drivers/input/serio/altera_ps2.c')
| -rw-r--r-- | drivers/input/serio/altera_ps2.c | 203 |
1 files changed, 203 insertions, 0 deletions
diff --git a/drivers/input/serio/altera_ps2.c b/drivers/input/serio/altera_ps2.c new file mode 100644 index 000000000000..320b7ca48bf8 --- /dev/null +++ b/drivers/input/serio/altera_ps2.c @@ -0,0 +1,203 @@ +/* + * Altera University Program PS2 controller driver + * + * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw> + * + * Based on sa1111ps2.c, which is: + * Copyright (C) 2002 Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/input.h> +#include <linux/serio.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> +#include <linux/io.h> + +#define DRV_NAME "altera_ps2" + +struct ps2if { + struct serio *io; + struct resource *iomem_res; + void __iomem *base; + unsigned irq; +}; + +/* + * Read all bytes waiting in the PS2 port. There should be + * at the most one, but we loop for safety. + */ +static irqreturn_t altera_ps2_rxint(int irq, void *dev_id) +{ + struct ps2if *ps2if = dev_id; + unsigned int status; + int handled = IRQ_NONE; + + while ((status = readl(ps2if->base)) & 0xffff0000) { + serio_interrupt(ps2if->io, status & 0xff, 0); + handled = IRQ_HANDLED; + } + + return handled; +} + +/* + * Write a byte to the PS2 port. + */ +static int altera_ps2_write(struct serio *io, unsigned char val) +{ + struct ps2if *ps2if = io->port_data; + + writel(val, ps2if->base); + return 0; +} + +static int altera_ps2_open(struct serio *io) +{ + struct ps2if *ps2if = io->port_data; + + /* clear fifo */ + while (readl(ps2if->base) & 0xffff0000) + /* empty */; + + writel(1, ps2if->base + 4); /* enable rx irq */ + return 0; +} + +static void altera_ps2_close(struct serio *io) +{ + struct ps2if *ps2if = io->port_data; + + writel(0, ps2if->base); /* disable rx irq */ +} + +/* + * Add one device to this driver. + */ +static int __devinit altera_ps2_probe(struct platform_device *pdev) +{ + struct ps2if *ps2if; + struct serio *serio; + int error, irq; + + ps2if = kzalloc(sizeof(struct ps2if), GFP_KERNEL); + serio = kzalloc(sizeof(struct serio), GFP_KERNEL); + if (!ps2if || !serio) { + error = -ENOMEM; + goto err_free_mem; + } + + serio->id.type = SERIO_8042; + serio->write = altera_ps2_write; + serio->open = altera_ps2_open; + serio->close = altera_ps2_close; + strlcpy(serio->name, dev_name(&pdev->dev), sizeof(serio->name)); + strlcpy(serio->phys, dev_name(&pdev->dev), sizeof(serio->phys)); + serio->port_data = ps2if; + serio->dev.parent = &pdev->dev; + ps2if->io = serio; + + ps2if->iomem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (ps2if->iomem_res == NULL) { + error = -ENOENT; + goto err_free_mem; + } + + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + error = -ENXIO; + goto err_free_mem; + } + ps2if->irq = irq; + + if (!request_mem_region(ps2if->iomem_res->start, + resource_size(ps2if->iomem_res), pdev->name)) { + error = -EBUSY; + goto err_free_mem; + } + + ps2if->base = ioremap(ps2if->iomem_res->start, + resource_size(ps2if->iomem_res)); + if (!ps2if->base) { + error = -ENOMEM; + goto err_free_res; + } + + error = request_irq(ps2if->irq, altera_ps2_rxint, 0, pdev->name, ps2if); + if (error) { + dev_err(&pdev->dev, "could not allocate IRQ %d: %d\n", + ps2if->irq, error); + goto err_unmap; + } + + dev_info(&pdev->dev, "base %p, irq %d\n", ps2if->base, ps2if->irq); + + serio_register_port(ps2if->io); + platform_set_drvdata(pdev, ps2if); + + return 0; + + err_unmap: + iounmap(ps2if->base); + err_free_res: + release_mem_region(ps2if->iomem_res->start, + resource_size(ps2if->iomem_res)); + err_free_mem: + kfree(ps2if); + kfree(serio); + return error; +} + +/* + * Remove one device from this driver. + */ +static int __devexit altera_ps2_remove(struct platform_device *pdev) +{ + struct ps2if *ps2if = platform_get_drvdata(pdev); + + platform_set_drvdata(pdev, NULL); + serio_unregister_port(ps2if->io); + free_irq(ps2if->irq, ps2if); + iounmap(ps2if->base); + release_mem_region(ps2if->iomem_res->start, + resource_size(ps2if->iomem_res)); + kfree(ps2if); + + return 0; +} + +/* + * Our device driver structure + */ +static struct platform_driver altera_ps2_driver = { + .probe = altera_ps2_probe, + .remove = __devexit_p(altera_ps2_remove), + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init altera_ps2_init(void) +{ + return platform_driver_register(&altera_ps2_driver); +} + +static void __exit altera_ps2_exit(void) +{ + platform_driver_unregister(&altera_ps2_driver); +} + +module_init(altera_ps2_init); +module_exit(altera_ps2_exit); + +MODULE_DESCRIPTION("Altera University Program PS2 controller driver"); +MODULE_AUTHOR("Thomas Chou <thomas@wytron.com.tw>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" DRV_NAME); |