| /* |
| * 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"); |
| |