--- /dev/null
+/*
+ * Xilinx XPS PS/2 device driver
+ *
+ * (c) 2005 MontaVista Software, Inc.
+ * (c) 2008 Xilinx, Inc.
+ *
+ * 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, or (at your
+ * option) any later version.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+
+#include <linux/module.h>
+#include <linux/serio.h>
+#include <linux/interrupt.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/io.h>
+
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+
+#define DRIVER_NAME "xilinx_ps2"
+
+/* Register offsets for the xps2 device */
+#define XPS2_SRST_OFFSET 0x00000000 /* Software Reset register */
+#define XPS2_STATUS_OFFSET 0x00000004 /* Status register */
+#define XPS2_RX_DATA_OFFSET 0x00000008 /* Receive Data register */
+#define XPS2_TX_DATA_OFFSET 0x0000000C /* Transmit Data register */
+#define XPS2_GIER_OFFSET 0x0000002C /* Global Interrupt Enable reg */
+#define XPS2_IPISR_OFFSET 0x00000030 /* Interrupt Status register */
+#define XPS2_IPIER_OFFSET 0x00000038 /* Interrupt Enable register */
+
+/* Reset Register Bit Definitions */
+#define XPS2_SRST_RESET 0x0000000A /* Software Reset */
+
+/* Status Register Bit Positions */
+#define XPS2_STATUS_RX_FULL 0x00000001 /* Receive Full */
+#define XPS2_STATUS_TX_FULL 0x00000002 /* Transmit Full */
+
+/* Bit definitions for ISR/IER registers. Both the registers have the same bit
+ * definitions and are only defined once. */
+#define XPS2_IPIXR_WDT_TOUT 0x00000001 /* Watchdog Timeout Interrupt */
+#define XPS2_IPIXR_TX_NOACK 0x00000002 /* Transmit No ACK Interrupt */
+#define XPS2_IPIXR_TX_ACK 0x00000004 /* Transmit ACK (Data) Interrupt */
+#define XPS2_IPIXR_RX_OVF 0x00000008 /* Receive Overflow Interrupt */
+#define XPS2_IPIXR_RX_ERR 0x00000010 /* Receive Error Interrupt */
+#define XPS2_IPIXR_RX_FULL 0x00000020 /* Receive Data Interrupt */
+
+/* Mask for all the Transmit Interrupts */
+#define XPS2_IPIXR_TX_ALL (XPS2_IPIXR_TX_NOACK | XPS2_IPIXR_TX_ACK)
+
+/* Mask for all the Receive Interrupts */
+#define XPS2_IPIXR_RX_ALL (XPS2_IPIXR_RX_OVF | XPS2_IPIXR_RX_ERR | \
+ XPS2_IPIXR_RX_FULL)
+
+/* Mask for all the Interrupts */
+#define XPS2_IPIXR_ALL (XPS2_IPIXR_TX_ALL | XPS2_IPIXR_RX_ALL | \
+ XPS2_IPIXR_WDT_TOUT)
+
+/* Global Interrupt Enable mask */
+#define XPS2_GIER_GIE_MASK 0x80000000
+
+struct xps2data {
+ int irq;
+ u32 phys_addr;
+ u32 remap_size;
+ spinlock_t lock;
+ u8 rxb; /* Rx buffer */
+ void __iomem *base_address; /* virt. address of control registers */
+ unsigned int dfl;
+ struct serio serio; /* serio */
+};
+
+/************************************/
+/* XPS PS/2 data transmission calls */
+/************************************/
+
+/*
+ * xps2_recv() will attempt to receive a byte of data from the PS/2 port.
+ */
+static int xps2_recv(struct xps2data *drvdata, u8 *byte)
+{
+ u32 sr;
+ int status = -1;
+
+ /* If there is data available in the PS/2 receiver, read it */
+ sr = in_be32(drvdata->base_address + XPS2_STATUS_OFFSET);
+ if (sr & XPS2_STATUS_RX_FULL) {
+ *byte = in_be32(drvdata->base_address + XPS2_RX_DATA_OFFSET);
+ status = 0;
+ }
+
+ return status;
+}
+
+/*********************/
+/* Interrupt handler */
+/*********************/
+static irqreturn_t xps2_interrupt(int irq, void *dev_id)
+{
+ struct xps2data *drvdata = dev_id;
+ u32 intr_sr;
+ u8 c;
+ int status;
+
+ /* Get the PS/2 interrupts and clear them */
+ intr_sr = in_be32(drvdata->base_address + XPS2_IPISR_OFFSET);
+ out_be32(drvdata->base_address + XPS2_IPISR_OFFSET, intr_sr);
+
+ /* Check which interrupt is active */
+ if (intr_sr & XPS2_IPIXR_RX_OVF)
+ printk(KERN_WARNING "%s: receive overrun error\n",
+ drvdata->serio.name);
+
+ if (intr_sr & XPS2_IPIXR_RX_ERR)
+ drvdata->dfl |= SERIO_PARITY;
+
+ if (intr_sr & (XPS2_IPIXR_TX_NOACK | XPS2_IPIXR_WDT_TOUT))
+ drvdata->dfl |= SERIO_TIMEOUT;
+
+ if (intr_sr & XPS2_IPIXR_RX_FULL) {
+ status = xps2_recv(drvdata, &drvdata->rxb);
+
+ /* Error, if a byte is not received */
+ if (status) {
+ printk(KERN_ERR
+ "%s: wrong rcvd byte count (%d)\n",
+ drvdata->serio.name, status);
+ } else {
+ c = drvdata->rxb;
+ serio_interrupt(&drvdata->serio, c, drvdata->dfl);
+ drvdata->dfl = 0;
+ }
+ }
+
+ if (intr_sr & XPS2_IPIXR_TX_ACK)
+ drvdata->dfl = 0;
+
+ return IRQ_HANDLED;
+}
+
+/*******************/
+/* serio callbacks */
+/*******************/
+
+/*
+ * sxps2_write() sends a byte out through the PS/2 interface.
+ */
+static int sxps2_write(struct serio *pserio, unsigned char c)
+{
+ struct xps2data *drvdata = pserio->port_data;
+ unsigned long flags;
+ u32 sr;
+ int status = -1;
+
+ spin_lock_irqsave(&drvdata->lock, flags);
+
+ /* If the PS/2 transmitter is empty send a byte of data */
+ sr = in_be32(drvdata->base_address + XPS2_STATUS_OFFSET);
+ if (!(sr & XPS2_STATUS_TX_FULL)) {
+ out_be32(drvdata->base_address + XPS2_TX_DATA_OFFSET, c);
+ status = 0;
+ }
+
+ spin_unlock_irqrestore(&drvdata->lock, flags);
+
+ return status;
+}
+
+/*
+ * sxps2_open() is called when a port is open by the higher layer.
+ */
+static int sxps2_open(struct serio *pserio)
+{
+ struct xps2data *drvdata = pserio->port_data;
+ int retval;
+
+ retval = request_irq(drvdata->irq, &xps2_interrupt, 0,
+ DRIVER_NAME, drvdata);
+ if (retval) {
+ printk(KERN_ERR
+ "%s: Couldn't allocate interrupt %d\n",
+ drvdata->serio.name, drvdata->irq);
+ return retval;
+ }
+
+ /* start reception by enabling the interrupts */
+ out_be32(drvdata->base_address + XPS2_GIER_OFFSET, XPS2_GIER_GIE_MASK);
+ out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, XPS2_IPIXR_RX_ALL);
+ (void)xps2_recv(drvdata, &drvdata->rxb);
+
+ return 0; /* success */
+}
+
+/*
+ * sxps2_close() frees the interrupt.
+ */
+static void sxps2_close(struct serio *pserio)
+{
+ struct xps2data *drvdata = pserio->port_data;
+
+ /* Disable the PS2 interrupts */
+ out_be32(drvdata->base_address + XPS2_GIER_OFFSET, 0x00);
+ out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, 0x00);
+ free_irq(drvdata->irq, drvdata);
+}
+
+/*********************/
+/* Device setup code */
+/*********************/
+
+static int xps2_setup(struct device *dev, struct resource *regs_res,
+ struct resource *irq_res)
+{
+ struct xps2data *drvdata;
+ struct serio *serio;
+ unsigned long remap_size;
+ int retval;
+
+ if (!dev)
+ return -EINVAL;
+
+ if (!regs_res || !irq_res) {
+ dev_err(dev, "IO resource(s) not found\n");
+ return -EINVAL;
+ }
+
+ drvdata = kzalloc(sizeof(struct xps2data), GFP_KERNEL);
+ if (!drvdata) {
+ dev_err(dev, "Couldn't allocate device private record\n");
+ return -ENOMEM;
+ }
+
+ dev_set_drvdata(dev, drvdata);
+
+ spin_lock_init(&drvdata->lock);
+ drvdata->irq = irq_res->start;
+
+ remap_size = regs_res->end - regs_res->start + 1;
+ if (!request_mem_region(regs_res->start, remap_size, DRIVER_NAME)) {
+ dev_err(dev, "Couldn't lock memory region at 0x%08X\n",
+ (unsigned int)regs_res->start);
+ retval = -EBUSY;
+ goto failed1;
+ }
+
+ /* Fill in configuration data and add them to the list */
+ drvdata->phys_addr = regs_res->start;
+ drvdata->remap_size = remap_size;
+ drvdata->base_address = ioremap(regs_res->start, remap_size);
+ if (drvdata->base_address == NULL) {
+ dev_err(dev, "Couldn't ioremap memory at 0x%08X\n",
+ (unsigned int)regs_res->start);
+ retval = -EFAULT;
+ goto failed2;
+ }
+
+ /* Disable all the interrupts, just in case */
+ out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, 0);
+
+ /* Reset the PS2 device and abort any current transaction, to make sure
+ * we have the PS2 in a good state */
+ out_be32(drvdata->base_address + XPS2_SRST_OFFSET, XPS2_SRST_RESET);
+
+ dev_info(dev, "Xilinx PS2 at 0x%08X mapped to 0x%08X, irq=%d\n",
+ drvdata->phys_addr, (u32)drvdata->base_address, drvdata->irq);
+
+ serio = &drvdata->serio;
+ serio->id.type = SERIO_8042;
+ serio->write = sxps2_write;
+ serio->open = sxps2_open;
+ serio->close = sxps2_close;
+ serio->port_data = drvdata;
+ serio->dev.parent = dev;
+ snprintf(serio->name, sizeof(serio->name),
+ "Xilinx XPS PS/2 at %08X", drvdata->phys_addr);
+ snprintf(serio->phys, sizeof(serio->phys),
+ "xilinxps2/serio at %08X", drvdata->phys_addr);
+ serio_register_port(serio);
+
+ return 0; /* success */
+
+failed2:
+ release_mem_region(regs_res->start, remap_size);
+failed1:
+ kfree(drvdata);
+ dev_set_drvdata(dev, NULL);
+
+ return retval;
+}
+
+/***************************/
+/* OF Platform Bus Support */
+/***************************/
+
+static int __devinit xps2_of_probe(struct of_device *ofdev, const struct
+ of_device_id * match)
+{
+ struct resource r_irq; /* Interrupt resources */
+ struct resource r_mem; /* IO mem resources */
+ int rc = 0;
+
+ printk(KERN_INFO "Device Tree Probing \'%s\'\n",
+ ofdev->node->name);
+
+ /* Get iospace for the device */
+ rc = of_address_to_resource(ofdev->node, 0, &r_mem);
+ if (rc) {
+ dev_err(&ofdev->dev, "invalid address\n");
+ return rc;
+ }
+
+ /* Get IRQ for the device */
+ rc = of_irq_to_resource(ofdev->node, 0, &r_irq);
+ if (rc == NO_IRQ) {
+ dev_err(&ofdev->dev, "no IRQ found\n");
+ return rc;
+ }
+
+ return xps2_setup(&ofdev->dev, &r_mem, &r_irq);
+}
+
+static int __devexit xps2_of_remove(struct of_device *of_dev)
+{
+ struct device *dev = &of_dev->dev;
+ struct xps2data *drvdata;
+
+ if (!dev)
+ return -EINVAL;
+
+ drvdata = dev_get_drvdata(dev);
+
+ serio_unregister_port(&drvdata->serio);
+ iounmap(drvdata->base_address);
+ release_mem_region(drvdata->phys_addr, drvdata->remap_size);
+ kfree(drvdata);
+
+ dev_set_drvdata(dev, NULL);
+
+ return 0; /* success */
+}
+
+/* Match table for of_platform binding */
+static struct of_device_id xps2_of_match[] __devinitdata = {
+ { .compatible = "xlnx,xps-ps2-1.00.a", },
+ { /* end of list */ },
+};
+MODULE_DEVICE_TABLE(of, xps2_of_match);
+
+static struct of_platform_driver xps2_of_driver = {
+ .name = DRIVER_NAME,
+ .match_table = xps2_of_match,
+ .probe = xps2_of_probe,
+ .remove = __devexit_p(xps2_of_remove),
+};
+
+static int __init xps2_init(void)
+{
+ return of_register_platform_driver(&xps2_of_driver);
+}
+
+static void __exit xps2_cleanup(void)
+{
+ of_unregister_platform_driver(&xps2_of_driver);
+}
+
+module_init(xps2_init);
+module_exit(xps2_cleanup);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION("Xilinx XPS PS/2 driver");
+MODULE_LICENSE("GPL");
+
projects / karo-tx-linux.git / commitdiff