/* * linux/drivers/input/serio/sa1111ps2.c * * 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 as published by * the Free Software Foundation; either version 2 of the License. */ #include <linux/module.h> #include <linux/init.h> #include <linux/input.h> #include <linux/serio.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/ioport.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <asm/io.h> #include <asm/hardware/sa1111.h> #define PS2CR 0x0000 #define PS2STAT 0x0004 #define PS2DATA 0x0008 #define PS2CLKDIV 0x000c #define PS2PRECNT 0x0010 #define PS2CR_ENA 0x08 #define PS2CR_FKD 0x02 #define PS2CR_FKC 0x01 #define PS2STAT_STP 0x0100 #define PS2STAT_TXE 0x0080 #define PS2STAT_TXB 0x0040 #define PS2STAT_RXF 0x0020 #define PS2STAT_RXB 0x0010 #define PS2STAT_ENA 0x0008 #define PS2STAT_RXP 0x0004 #define PS2STAT_KBD 0x0002 #define PS2STAT_KBC 0x0001 struct ps2if { struct serio *io; struct sa1111_dev *dev; void __iomem *base; unsigned int open; spinlock_t lock; unsigned int head; unsigned int tail; unsigned char buf[4]; }; /* * Read all bytes waiting in the PS2 port. There should be * at the most one, but we loop for safety. If there was a * framing error, we have to manually clear the status. */ static irqreturn_t ps2_rxint(int irq, void *dev_id) { struct ps2if *ps2if = dev_id; unsigned int scancode, flag, status; status = sa1111_readl(ps2if->base + PS2STAT); while (status & PS2STAT_RXF) { if (status & PS2STAT_STP) sa1111_writel(PS2STAT_STP, ps2if->base + PS2STAT); flag = (status & PS2STAT_STP ? SERIO_FRAME : 0) | (status & PS2STAT_RXP ? 0 : SERIO_PARITY); scancode = sa1111_readl(ps2if->base + PS2DATA) & 0xff; if (hweight8(scancode) & 1) flag ^= SERIO_PARITY; serio_interrupt(ps2if->io, scancode, flag); status = sa1111_readl(ps2if->base + PS2STAT); } return IRQ_HANDLED; } /* * Completion of ps2 write */ static irqreturn_t ps2_txint(int irq, void *dev_id) { struct ps2if *ps2if = dev_id; unsigned int status; spin_lock(&ps2if->lock); status = sa1111_readl(ps2if->base + PS2STAT); if (ps2if->head == ps2if->tail) { disable_irq_nosync(irq); /* done */ } else if (status & PS2STAT_TXE) { sa1111_writel(ps2if->buf[ps2if->tail], ps2if->base + PS2DATA); ps2if->tail = (ps2if->tail + 1) & (sizeof(ps2if->buf) - 1); } spin_unlock(&ps2if->lock); return IRQ_HANDLED; } /* * Write a byte to the PS2 port. We have to wait for the * port to indicate that the transmitter is empty. */ static int ps2_write(struct serio *io, unsigned char val) { struct ps2if *ps2if = io->port_data; unsigned long flags; unsigned int head; spin_lock_irqsave(&ps2if->lock, flags); /* * If the TX register is empty, we can go straight out. */ if (sa1111_readl(ps2if->base + PS2STAT) & PS2STAT_TXE) { sa1111_writel(val, ps2if->base + PS2DATA); } else { if (ps2if->head == ps2if->tail) enable_irq(ps2if->dev->irq[1]); head = (ps2if->head + 1) & (sizeof(ps2if->buf) - 1); if (head != ps2if->tail) { ps2if->buf[ps2if->head] = val; ps2if->head = head; } } spin_unlock_irqrestore(&ps2if->lock, flags); return 0; } static int ps2_open(struct serio *io) { struct ps2if *ps2if = io->port_data; int ret; ret = sa1111_enable_device(ps2if->dev); if (ret) return ret; ret = request_irq(ps2if->dev->irq[0], ps2_rxint, 0, SA1111_DRIVER_NAME(ps2if->dev), ps2if); if (ret) { printk(KERN_ERR "sa1111ps2: could not allocate IRQ%d: %d\n", ps2if->dev->irq[0], ret); sa1111_disable_device(ps2if->dev); return ret; } ret = request_irq(ps2if->dev->irq[1], ps2_txint, 0, SA1111_DRIVER_NAME(ps2if->dev), ps2if); if (ret) { printk(KERN_ERR "sa1111ps2: could not allocate IRQ%d: %d\n", ps2if->dev->irq[1], ret); free_irq(ps2if->dev->irq[0], ps2if); sa1111_disable_device(ps2if->dev); return ret; } ps2if->open = 1; enable_irq_wake(ps2if->dev->irq[0]); sa1111_writel(PS2CR_ENA, ps2if->base + PS2CR); return 0; } static void ps2_close(struct serio *io) { struct ps2if *ps2if = io->port_data; sa1111_writel(0, ps2if->base + PS2CR); disable_irq_wake(ps2if->dev->irq[0]); ps2if->open = 0; free_irq(ps2if->dev->irq[1], ps2if); free_irq(ps2if->dev->irq[0], ps2if); sa1111_disable_device(ps2if->dev); } /* * Clear the input buffer. */ static void ps2_clear_input(struct ps2if *ps2if) { int maxread = 100; while (maxread--) { if ((sa1111_readl(ps2if->base + PS2DATA) & 0xff) == 0xff) break; } } static unsigned int ps2_test_one(struct ps2if *ps2if, unsigned int mask) { unsigned int val; sa1111_writel(PS2CR_ENA | mask, ps2if->base + PS2CR); udelay(2); val = sa1111_readl(ps2if->base + PS2STAT); return val & (PS2STAT_KBC | PS2STAT_KBD); } /* * Test the keyboard interface. We basically check to make sure that * we can drive each line to the keyboard independently of each other. */ static int ps2_test(struct ps2if *ps2if) { unsigned int stat; int ret = 0; stat = ps2_test_one(ps2if, PS2CR_FKC); if (stat != PS2STAT_KBD) { printk("PS/2 interface test failed[1]: %02x\n", stat); ret = -ENODEV; } stat = ps2_test_one(ps2if, 0); if (stat != (PS2STAT_KBC | PS2STAT_KBD)) { printk("PS/2 interface test failed[2]: %02x\n", stat); ret = -ENODEV; } stat = ps2_test_one(ps2if, PS2CR_FKD); if (stat != PS2STAT_KBC) { printk("PS/2 interface test failed[3]: %02x\n", stat); ret = -ENODEV; } sa1111_writel(0, ps2if->base + PS2CR); return ret; } /* * Add one device to this driver. */ static int ps2_probe(struct sa1111_dev *dev) { struct ps2if *ps2if; struct serio *serio; int ret; ps2if = kzalloc(sizeof(struct ps2if), GFP_KERNEL); serio = kzalloc(sizeof(struct serio), GFP_KERNEL); if (!ps2if || !serio) { ret = -ENOMEM; goto free; } serio->id.type = SERIO_8042; serio->write = ps2_write; serio->open = ps2_open; serio->close = ps2_close; strlcpy(serio->name, dev_name(&dev->dev), sizeof(serio->name)); strlcpy(serio->phys, dev_name(&dev->dev), sizeof(serio->phys)); serio->port_data = ps2if; serio->dev.parent = &dev->dev; ps2if->io = serio; ps2if->dev = dev; sa1111_set_drvdata(dev, ps2if); spin_lock_init(&ps2if->lock); /* * Request the physical region for this PS2 port. */ if (!request_mem_region(dev->res.start, dev->res.end - dev->res.start + 1, SA1111_DRIVER_NAME(dev))) { ret = -EBUSY; goto free; } /* * Our parent device has already mapped the region. */ ps2if->base = dev->mapbase; sa1111_enable_device(ps2if->dev); /* Incoming clock is 8MHz */ sa1111_writel(0, ps2if->base + PS2CLKDIV); sa1111_writel(127, ps2if->base + PS2PRECNT); /* * Flush any pending input. */ ps2_clear_input(ps2if); /* * Test the keyboard interface. */ ret = ps2_test(ps2if); if (ret) goto out; /* * Flush any pending input. */ ps2_clear_input(ps2if); sa1111_disable_device(ps2if->dev); serio_register_port(ps2if->io); return 0; out: sa1111_disable_device(ps2if->dev); release_mem_region(dev->res.start, resource_size(&dev->res)); free: sa1111_set_drvdata(dev, NULL); kfree(ps2if); kfree(serio); return ret; } /* * Remove one device from this driver. */ static int ps2_remove(struct sa1111_dev *dev) { struct ps2if *ps2if = sa1111_get_drvdata(dev); serio_unregister_port(ps2if->io); release_mem_region(dev->res.start, resource_size(&dev->res)); sa1111_set_drvdata(dev, NULL); kfree(ps2if); return 0; } /* * Our device driver structure */ static struct sa1111_driver ps2_driver = { .drv = { .name = "sa1111-ps2", .owner = THIS_MODULE, }, .devid = SA1111_DEVID_PS2, .probe = ps2_probe, .remove = ps2_remove, }; static int __init ps2_init(void) { return sa1111_driver_register(&ps2_driver); } static void __exit ps2_exit(void) { sa1111_driver_unregister(&ps2_driver); } module_init(ps2_init); module_exit(ps2_exit); MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>"); MODULE_DESCRIPTION("SA1111 PS2 controller driver"); MODULE_LICENSE("GPL");