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Diffstat (limited to 'drivers/input/serio/sa1111ps2.c')
-rw-r--r--drivers/input/serio/sa1111ps2.c386
1 files changed, 386 insertions, 0 deletions
diff --git a/drivers/input/serio/sa1111ps2.c b/drivers/input/serio/sa1111ps2.c
new file mode 100644
index 000000000..2724c3aa5
--- /dev/null
+++ b/drivers/input/serio/sa1111ps2.c
@@ -0,0 +1,386 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/drivers/input/serio/sa1111ps2.c
+ *
+ * Copyright (C) 2002 Russell King
+ */
+#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;
+ int rx_irq;
+ int tx_irq;
+ 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 = readl_relaxed(ps2if->base + PS2STAT);
+ while (status & PS2STAT_RXF) {
+ if (status & PS2STAT_STP)
+ writel_relaxed(PS2STAT_STP, ps2if->base + PS2STAT);
+
+ flag = (status & PS2STAT_STP ? SERIO_FRAME : 0) |
+ (status & PS2STAT_RXP ? 0 : SERIO_PARITY);
+
+ scancode = readl_relaxed(ps2if->base + PS2DATA) & 0xff;
+
+ if (hweight8(scancode) & 1)
+ flag ^= SERIO_PARITY;
+
+ serio_interrupt(ps2if->io, scancode, flag);
+
+ status = readl_relaxed(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 = readl_relaxed(ps2if->base + PS2STAT);
+ if (ps2if->head == ps2if->tail) {
+ disable_irq_nosync(irq);
+ /* done */
+ } else if (status & PS2STAT_TXE) {
+ writel_relaxed(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 (readl_relaxed(ps2if->base + PS2STAT) & PS2STAT_TXE) {
+ writel_relaxed(val, ps2if->base + PS2DATA);
+ } else {
+ if (ps2if->head == ps2if->tail)
+ enable_irq(ps2if->tx_irq);
+ 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->rx_irq, ps2_rxint, 0,
+ SA1111_DRIVER_NAME(ps2if->dev), ps2if);
+ if (ret) {
+ printk(KERN_ERR "sa1111ps2: could not allocate IRQ%d: %d\n",
+ ps2if->rx_irq, ret);
+ sa1111_disable_device(ps2if->dev);
+ return ret;
+ }
+
+ ret = request_irq(ps2if->tx_irq, ps2_txint, 0,
+ SA1111_DRIVER_NAME(ps2if->dev), ps2if);
+ if (ret) {
+ printk(KERN_ERR "sa1111ps2: could not allocate IRQ%d: %d\n",
+ ps2if->tx_irq, ret);
+ free_irq(ps2if->rx_irq, ps2if);
+ sa1111_disable_device(ps2if->dev);
+ return ret;
+ }
+
+ ps2if->open = 1;
+
+ enable_irq_wake(ps2if->rx_irq);
+
+ writel_relaxed(PS2CR_ENA, ps2if->base + PS2CR);
+ return 0;
+}
+
+static void ps2_close(struct serio *io)
+{
+ struct ps2if *ps2if = io->port_data;
+
+ writel_relaxed(0, ps2if->base + PS2CR);
+
+ disable_irq_wake(ps2if->rx_irq);
+
+ ps2if->open = 0;
+
+ free_irq(ps2if->tx_irq, ps2if);
+ free_irq(ps2if->rx_irq, ps2if);
+
+ sa1111_disable_device(ps2if->dev);
+}
+
+/*
+ * Clear the input buffer.
+ */
+static void ps2_clear_input(struct ps2if *ps2if)
+{
+ int maxread = 100;
+
+ while (maxread--) {
+ if ((readl_relaxed(ps2if->base + PS2DATA) & 0xff) == 0xff)
+ break;
+ }
+}
+
+static unsigned int ps2_test_one(struct ps2if *ps2if,
+ unsigned int mask)
+{
+ unsigned int val;
+
+ writel_relaxed(PS2CR_ENA | mask, ps2if->base + PS2CR);
+
+ udelay(10);
+
+ val = readl_relaxed(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;
+ }
+
+ writel_relaxed(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;
+ strscpy(serio->name, dev_name(&dev->dev), sizeof(serio->name));
+ strscpy(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);
+
+ ps2if->rx_irq = sa1111_get_irq(dev, 0);
+ if (ps2if->rx_irq <= 0) {
+ ret = ps2if->rx_irq ? : -ENXIO;
+ goto free;
+ }
+
+ ps2if->tx_irq = sa1111_get_irq(dev, 1);
+ if (ps2if->tx_irq <= 0) {
+ ret = ps2if->tx_irq ? : -ENXIO;
+ goto free;
+ }
+
+ /*
+ * 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 */
+ writel_relaxed(0, ps2if->base + PS2CLKDIV);
+ writel_relaxed(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 void 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);
+}
+
+/*
+ * 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");