[PATCH] powerpc: Xilinx: PS2: Added new XPS PS2 driver
John Linn
john.linn at xilinx.com
Tue Jul 1 00:24:48 EST 2008
Added a new driver for Xilinx XPS PS2 IP. This driver is
a flat driver to better match the Linux driver pattern.
Signed-off-by: Sadanand <sadanan at xilinx.com>
Signed-off-by: John Linn <john.linn at xilinx.com>
---
drivers/input/serio/Kconfig | 5 +
drivers/input/serio/Makefile | 1 +
drivers/input/serio/xilinx_ps2.c | 464 ++++++++++++++++++++++++++++++++++++++
drivers/input/serio/xilinx_ps2.h | 97 ++++++++
4 files changed, 567 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/serio/xilinx_ps2.c
create mode 100644 drivers/input/serio/xilinx_ps2.h
diff --git a/drivers/input/serio/Kconfig b/drivers/input/serio/Kconfig
index ec4b661..0e62b39 100644
--- a/drivers/input/serio/Kconfig
+++ b/drivers/input/serio/Kconfig
@@ -190,4 +190,9 @@ config SERIO_RAW
To compile this driver as a module, choose M here: the
module will be called serio_raw.
+config SERIO_XILINX_XPS_PS2
+ tristate "Xilinx XPS PS/2 Controller Support"
+ help
+ This driver supports XPS PS/2 IP from Xilinx EDK.
+
endif
diff --git a/drivers/input/serio/Makefile b/drivers/input/serio/Makefile
index 38b8868..9b6c813 100644
--- a/drivers/input/serio/Makefile
+++ b/drivers/input/serio/Makefile
@@ -21,3 +21,4 @@ obj-$(CONFIG_SERIO_PCIPS2) += pcips2.o
obj-$(CONFIG_SERIO_MACEPS2) += maceps2.o
obj-$(CONFIG_SERIO_LIBPS2) += libps2.o
obj-$(CONFIG_SERIO_RAW) += serio_raw.o
+obj-$(CONFIG_SERIO_XILINX_XPS_PS2) += xilinx_ps2.o
diff --git a/drivers/input/serio/xilinx_ps2.c b/drivers/input/serio/xilinx_ps2.c
new file mode 100644
index 0000000..670d47f
--- /dev/null
+++ b/drivers/input/serio/xilinx_ps2.c
@@ -0,0 +1,464 @@
+/*
+ * xilinx_ps2.c
+ *
+ * Xilinx PS/2 driver to interface PS/2 component to Linux
+ *
+ * Author: MontaVista Software, Inc.
+ * source at mvista.com
+ *
+ * (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 <asm/io.h>
+
+#ifdef CONFIG_OF /* For open firmware */
+ #include <linux/of_device.h>
+ #include <linux/of_platform.h>
+#endif /* CONFIG_OF */
+
+#include "xilinx_ps2.h"
+
+#define DRIVER_NAME "xilinx_ps2"
+#define DRIVER_DESCRIPTION "Xilinx XPS PS/2 driver"
+
+#define XPS2_NAME_DESC "Xilinx XPS PS/2 Port #%d"
+#define XPS2_PHYS_DESC "xilinxps2/serio%d"
+
+
+static DECLARE_MUTEX(cfg_sem);
+
+/*********************/
+/* Interrupt handler */
+/*********************/
+static irqreturn_t xps2_interrupt(int irq, void *dev_id)
+{
+ struct xps2data *drvdata = (struct xps2data *)dev_id;
+ u32 intr_sr;
+ u32 ier;
+ u8 c;
+ u8 retval;
+
+ /* 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_ERR "%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) {
+ retval = xps2_recv(drvdata, &drvdata->rxb);
+
+ /* Error, if 1 byte is not received */
+ if (retval != 1) {
+ printk(KERN_ERR
+ "%s: wrong rcvd byte count (%d)\n",
+ drvdata->serio.name, retval);
+ }
+ c = drvdata->rxb;
+ serio_interrupt(&drvdata->serio, c, drvdata->dfl);
+ drvdata->dfl = 0;
+ }
+
+ if (intr_sr & XPS2_IPIXR_TX_ACK) {
+
+ /* Disable the TX interrupts after the transmission is
+ * complete */
+ ier = in_be32(drvdata->base_address + XPS2_IPIER_OFFSET);
+ ier &= (~(XPS2_IPIXR_TX_ACK & XPS2_IPIXR_ALL ));
+ out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, ier);
+ drvdata->dfl = 0;
+ }
+
+ return IRQ_HANDLED;
+}
+
+/*******************/
+/* serio callbacks */
+/*******************/
+
+/*
+ * sxps2_write() sends a byte out through the PS/2 interface.
+ *
+ * The sole purpose of drvdata->tx_end is to prevent the driver
+ * from locking up in the do {} while; loop when nothing is connected
+ * to the given PS/2 port. That's why we do not try to recover
+ * from the transmission failure.
+ * drvdata->tx_end needs not to be initialized to some "far in the
+ * future" value, as the very first attempt to xps2_send() a byte
+ * is always successful, and drvdata->tx_end will be set to a proper
+ * value at that moment - before the 1st use in the comparison.
+ */
+static int sxps2_write(struct serio *pserio, unsigned char c)
+{
+ struct xps2data *drvdata = pserio->port_data;
+ unsigned long flags;
+ int retval;
+
+ do {
+ spin_lock_irqsave(&drvdata->lock, flags);
+ retval = xps2_send(drvdata, &c);
+ spin_unlock_irqrestore(&drvdata->lock, flags);
+
+ if (retval == 1) {
+ drvdata->tx_end = jiffies + HZ;
+ return 0; /* success */
+ }
+ } while (!time_after(jiffies, drvdata->tx_end));
+
+ return 1; /* transmission is frozen */
+}
+
+/*
+ * 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);
+}
+
+/*************************/
+/* XPS PS/2 driver calls */
+/*************************/
+
+/*
+ * xps2_initialize() initializes the Xilinx PS/2 device.
+ */
+static int xps2_initialize(struct xps2data *drvdata)
+{
+ /* 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);
+
+ return 0;
+}
+
+/*
+ * xps2_send() sends the specified byte of data to the PS/2 port in interrupt
+ * mode.
+ */
+static u8 xps2_send(struct xps2data *drvdata, u8 *byte)
+{
+ u32 sr;
+ u32 ier;
+ u8 retval = 0;
+
+ /* Enter a critical region by disabling the PS/2 transmit interrupts to
+ * allow this call to stop a previous operation that may be interrupt
+ * driven. Only stop the transmit interrupt since this critical region
+ * is not really exited in the normal manner */
+ ier = in_be32(drvdata->base_address + XPS2_IPIER_OFFSET);
+ ier &= (~(XPS2_IPIXR_TX_ALL & XPS2_IPIXR_ALL ));
+ out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, ier);
+
+ /* 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) == 0) {
+ out_be32(drvdata->base_address + XPS2_TX_DATA_OFFSET, *byte);
+ retval = 1;
+ }
+
+ /* Enable the TX interrupts to track the status of the transmission */
+ ier = in_be32(drvdata->base_address + XPS2_IPIER_OFFSET);
+ ier |= ((XPS2_IPIXR_TX_ALL | XPS2_IPIXR_WDT_TOUT ));
+ out_be32(drvdata->base_address + XPS2_IPIER_OFFSET, ier);
+
+ return retval; /* no. of bytes sent */
+}
+
+/*
+ * xps2_recv() will attempt to receive a byte of data from the PS/2 port.
+ */
+static u8 xps2_recv(struct xps2data *drvdata, u8 *byte)
+{
+ u32 sr;
+ u8 retval = 0;
+
+ /* 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);
+ retval = 1;
+ }
+
+ return retval; /* no. of bytes received */
+}
+
+/******************************/
+/* The platform device driver */
+/******************************/
+
+static int xps2_probe(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+
+ struct resource *irq_res = NULL; /* Interrupt resources */
+ struct resource *regs_res = NULL; /* IO mem resources */
+
+ if (!dev) {
+ dev_err(dev, "Probe called with NULL param\n");
+ return -EINVAL;
+ }
+
+ /* Find irq number, map the control registers in */
+ irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ regs_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ return xps2_setup(dev, pdev->id, regs_res, irq_res);
+}
+
+/*
+ * Shared device initialization code.
+ */
+static int xps2_setup(struct device *dev, int id, struct resource *regs_res,
+ struct resource *irq_res)
+{
+ struct xps2data *drvdata;
+ unsigned long remap_size;
+ int retval;
+
+ if (!dev)
+ return -EINVAL;
+
+ drvdata = kzalloc(sizeof(struct xps2data), GFP_KERNEL);
+ if (!drvdata) {
+ dev_err(dev, "Couldn't allocate device private record\n");
+ return -ENOMEM;
+ }
+ spin_lock_init(&drvdata->lock);
+ dev_set_drvdata(dev, (void *)drvdata);
+
+ if (!regs_res || !irq_res) {
+ dev_err(dev, "IO resource(s) not found\n");
+ retval = -EFAULT;
+ goto failed1;
+ }
+
+ 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;
+ }
+
+ /* Initialize the PS/2 interface */
+ down(&cfg_sem);
+ if (xps2_initialize(drvdata)) {
+ up(&cfg_sem);
+ dev_err(dev,"Could not initialize device\n");
+ retval = -ENODEV;
+ goto failed3;
+ }
+ up(&cfg_sem);
+
+ dev_info(dev, "Xilinx PS2 at 0x%08X mapped to 0x%08X, irq=%d\n",
+ drvdata->phys_addr, (u32)drvdata->base_address, drvdata->irq);
+
+ drvdata->serio.id.type = SERIO_8042;
+ drvdata->serio.write = sxps2_write;
+ drvdata->serio.open = sxps2_open;
+ drvdata->serio.close = sxps2_close;
+ drvdata->serio.port_data = drvdata;
+ drvdata->serio.dev.parent = dev;
+ snprintf(drvdata->serio.name, sizeof(drvdata->serio.name),
+ XPS2_NAME_DESC, id);
+ snprintf(drvdata->serio.phys, sizeof(drvdata->serio.phys),
+ XPS2_PHYS_DESC, id);
+ serio_register_port(&drvdata->serio);
+
+ return 0; /* success */
+
+failed3:
+ iounmap(drvdata->base_address);
+
+failed2:
+ release_mem_region(regs_res->start, remap_size);
+
+failed1:
+ kfree(drvdata);
+ dev_set_drvdata(dev, NULL);
+
+ return retval;
+}
+
+/*
+ * xps2_remove() dissociates the driver with the Xilinx PS/2 device.
+ */
+static int xps2_remove(struct device *dev)
+{
+ struct xps2data *drvdata;
+
+ if (!dev)
+ return -EINVAL;
+
+ drvdata = (struct xps2data *)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 */
+}
+
+static struct device_driver xps2_driver = {
+ .name = DRIVER_NAME,
+ .bus = &platform_bus_type,
+ .probe = xps2_probe,
+ .remove = xps2_remove
+};
+
+#ifdef CONFIG_OF
+static int __devinit xps2_of_probe(struct of_device *ofdev, const struct
+ of_device_id *match)
+{
+ struct resource r_irq_struct;
+ struct resource r_mem_struct;
+ struct resource *r_irq = &r_irq_struct; /* Interrupt resources */
+ struct resource *r_mem = &r_mem_struct; /* IO mem resources */
+ int rc = 0;
+ const unsigned int *id;
+
+ 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_warn(&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_warn(&ofdev->dev, "no IRQ found\n");
+ return rc;
+ }
+
+ id = of_get_property(ofdev->node, "port-number", NULL);
+ return xps2_setup(&ofdev->dev, id ? *id : -1, r_mem, r_irq);
+}
+
+static int __devexit xps2_of_remove(struct of_device *dev)
+{
+ return xps2_remove(&dev->dev);
+}
+
+static struct of_device_id __devinitdata xps2_of_match[] = {
+ { .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),
+};
+#endif /* CONFIG_OF */
+
+static int __init xps2_init(void)
+{
+ int status = driver_register(&xps2_driver);
+#ifdef CONFIG_OF
+ status |= of_register_platform_driver(&xps2_of_driver);
+#endif /* CONFIG_OF */
+ return status;
+}
+
+static void __exit xps2_cleanup(void)
+{
+ driver_unregister(&xps2_driver);
+#ifdef CONFIG_OF
+ of_unregister_platform_driver(&xps2_of_driver);
+#endif /* CONFIG_OF */
+}
+
+module_init(xps2_init);
+module_exit(xps2_cleanup);
+
+MODULE_AUTHOR("Xilinx, Inc.");
+MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
+MODULE_LICENSE("GPL");
+
diff --git a/drivers/input/serio/xilinx_ps2.h b/drivers/input/serio/xilinx_ps2.h
new file mode 100644
index 0000000..4db73ca
--- /dev/null
+++ b/drivers/input/serio/xilinx_ps2.h
@@ -0,0 +1,97 @@
+/*****************************************************************************
+ *
+ * Author: 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.
+ *
+ * XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS"
+ * AS A COURTESY TO YOU, SOLELY FOR USE IN DEVELOPING PROGRAMS AND
+ * SOLUTIONS FOR XILINX DEVICES. BY PROVIDING THIS DESIGN, CODE,
+ * OR INFORMATION AS ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE,
+ * APPLICATION OR STANDARD, XILINX IS MAKING NO REPRESENTATION
+ * THAT THIS IMPLEMENTATION IS FREE FROM ANY CLAIMS OF INFRINGEMENT,
+ * AND YOU ARE RESPONSIBLE FOR OBTAINING ANY RIGHTS YOU MAY REQUIRE
+ * FOR YOUR IMPLEMENTATION. XILINX EXPRESSLY DISCLAIMS ANY
+ * WARRANTY WHATSOEVER WITH RESPECT TO THE ADEQUACY OF THE
+ * IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OR
+ * REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM CLAIMS OF
+ * INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE.
+ *
+ * Xilinx products are not intended for use in life support appliances,
+ * devices, or systems. Use in such applications is expressly prohibited.
+ *
+ * (c) Copyright 2008 Xilinx Inc.
+ * All rights reserved.
+ *
+ * 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.
+ *
+ *****************************************************************************/
+
+#ifndef XILINX_PS2_H_ /* prevent circular inclusions */
+#define XILINX_PS2_H_ /* by using protection macros */
+
+/* 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 long tx_end;
+ unsigned int dfl;
+ struct serio serio; /* serio */
+};
+
+static u8 xps2_send(struct xps2data *drvdata, u8 *buffer_ptr);
+static u8 xps2_recv(struct xps2data *drvdata, u8 *buffer_ptr);
+static int xps2_initialize(struct xps2data *drvdata);
+static int xps2_setup(struct device *dev, int id, struct resource *regs_res,
+ struct resource *irq_res);
+
+#endif /* end of protection macro */
+
--
1.5.2.1
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