diff options
Diffstat (limited to 'drivers/input/serio/xilinx_ps2.c')
| -rw-r--r-- | drivers/input/serio/xilinx_ps2.c | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/drivers/input/serio/xilinx_ps2.c b/drivers/input/serio/xilinx_ps2.c new file mode 100644 index 00000000000..0ed044d5e68 --- /dev/null +++ b/drivers/input/serio/xilinx_ps2.c @@ -0,0 +1,380 @@ +/* + * 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"); + |