+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Xilinx XPS PS/2 device driver
- *
- * (c) 2005 MontaVista Software, Inc.
- * (c) 2008 Xilinx, Inc.
- */
-
-
-#include <linux/module.h>
-#include <linux/serio.h>
-#include <linux/interrupt.h>
-#include <linux/errno.h>
-#include <linux/slab.h>
-#include <linux/list.h>
-#include <linux/io.h>
-#include <linux/mod_devicetable.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
-#include <linux/platform_device.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;
- spinlock_t lock;
- void __iomem *base_address; /* virt. address of control registers */
- unsigned int flags;
- struct serio *serio; /* serio */
- struct device *dev;
-};
-
-/************************************/
-/* XPS PS/2 data transmission calls */
-/************************************/
-
-/**
- * xps2_recv() - attempts to receive a byte from the PS/2 port.
- * @drvdata: pointer to ps2 device private data structure
- * @byte: address where the read data will be copied
- *
- * If there is any data available in the PS/2 receiver, this functions reads
- * the data, otherwise it returns error.
- */
-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)
- dev_warn(drvdata->dev, "receive overrun error\n");
-
- if (intr_sr & XPS2_IPIXR_RX_ERR)
- drvdata->flags |= SERIO_PARITY;
-
- if (intr_sr & (XPS2_IPIXR_TX_NOACK | XPS2_IPIXR_WDT_TOUT))
- drvdata->flags |= SERIO_TIMEOUT;
-
- if (intr_sr & XPS2_IPIXR_RX_FULL) {
- status = xps2_recv(drvdata, &c);
-
- /* Error, if a byte is not received */
- if (status) {
- dev_err(drvdata->dev,
- "wrong rcvd byte count (%d)\n", status);
- } else {
- serio_interrupt(drvdata->serio, c, drvdata->flags);
- drvdata->flags = 0;
- }
- }
-
- return IRQ_HANDLED;
-}
-
-/*******************/
-/* serio callbacks */
-/*******************/
-
-/**
- * sxps2_write() - sends a byte out through the PS/2 port.
- * @pserio: pointer to the serio structure of the PS/2 port
- * @c: data that needs to be written to the PS/2 port
- *
- * This function checks if the PS/2 transmitter is empty and sends a byte.
- * Otherwise it returns error. Transmission fails only when nothing is connected
- * to the PS/2 port. Thats why, we do not try to resend the data in case of a
- * failure.
- */
-static int sxps2_write(struct serio *pserio, unsigned char c)
-{
- struct xps2data *drvdata = pserio->port_data;
- u32 sr;
-
- guard(spinlock_irqsave)(&drvdata->lock);
-
- /* 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)
- return -EAGAIN;
-
- out_be32(drvdata->base_address + XPS2_TX_DATA_OFFSET, c);
- return 0;
-}
-
-/**
- * sxps2_open() - called when a port is opened by the higher layer.
- * @pserio: pointer to the serio structure of the PS/2 device
- *
- * This function requests irq and enables interrupts for the PS/2 device.
- */
-static int sxps2_open(struct serio *pserio)
-{
- struct xps2data *drvdata = pserio->port_data;
- int error;
- u8 c;
-
- error = request_irq(drvdata->irq, &xps2_interrupt, 0,
- DRIVER_NAME, drvdata);
- if (error) {
- dev_err(drvdata->dev,
- "Couldn't allocate interrupt %d\n", drvdata->irq);
- return error;
- }
-
- /* 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, &c);
-
- return 0; /* success */
-}
-
-/**
- * sxps2_close() - frees the interrupt.
- * @pserio: pointer to the serio structure of the PS/2 device
- *
- * This function frees the irq and disables interrupts for the PS/2 device.
- */
-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);
-}
-
-/**
- * xps2_of_probe - probe method for the PS/2 device.
- * @ofdev: pointer to OF device structure
- *
- * This function probes the PS/2 device in the device tree.
- * It initializes the driver data structure and the hardware.
- * It returns 0, if the driver is bound to the PS/2 device, or a negative
- * value if there is an error.
- */
-static int xps2_of_probe(struct platform_device *ofdev)
-{
- struct resource r_mem; /* IO mem resources */
- struct xps2data *drvdata;
- struct serio *serio;
- struct device *dev = &ofdev->dev;
- resource_size_t remap_size, phys_addr;
- unsigned int irq;
- int error;
-
- dev_info(dev, "Device Tree Probing \'%pOFn\'\n", dev->of_node);
-
- /* Get iospace for the device */
- error = of_address_to_resource(dev->of_node, 0, &r_mem);
- if (error) {
- dev_err(dev, "invalid address\n");
- return error;
- }
-
- /* Get IRQ for the device */
- irq = irq_of_parse_and_map(dev->of_node, 0);
- if (!irq) {
- dev_err(dev, "no IRQ found\n");
- return -ENODEV;
- }
-
- drvdata = kzalloc_obj(*drvdata);
- serio = kzalloc_obj(*serio);
- if (!drvdata || !serio) {
- error = -ENOMEM;
- goto failed1;
- }
-
- spin_lock_init(&drvdata->lock);
- drvdata->irq = irq;
- drvdata->serio = serio;
- drvdata->dev = dev;
-
- phys_addr = r_mem.start;
- remap_size = resource_size(&r_mem);
- if (!request_mem_region(phys_addr, remap_size, DRIVER_NAME)) {
- dev_err(dev, "Couldn't lock memory region at 0x%08llX\n",
- (unsigned long long)phys_addr);
- error = -EBUSY;
- goto failed1;
- }
-
- /* Fill in configuration data and add them to the list */
- drvdata->base_address = ioremap(phys_addr, remap_size);
- if (drvdata->base_address == NULL) {
- dev_err(dev, "Couldn't ioremap memory at 0x%08llX\n",
- (unsigned long long)phys_addr);
- error = -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%08llX mapped to 0x%p, irq=%d\n",
- (unsigned long long)phys_addr, drvdata->base_address,
- drvdata->irq);
-
- 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 %08llX", (unsigned long long)phys_addr);
- snprintf(serio->phys, sizeof(serio->phys),
- "xilinxps2/serio at %08llX", (unsigned long long)phys_addr);
-
- serio_register_port(serio);
-
- platform_set_drvdata(ofdev, drvdata);
- return 0; /* success */
-
-failed2:
- release_mem_region(phys_addr, remap_size);
-failed1:
- kfree(serio);
- kfree(drvdata);
-
- return error;
-}
-
-/**
- * xps2_of_remove - unbinds the driver from the PS/2 device.
- * @of_dev: pointer to OF device structure
- *
- * This function is called if a device is physically removed from the system or
- * if the driver module is being unloaded. It frees any resources allocated to
- * the device.
- */
-static void xps2_of_remove(struct platform_device *of_dev)
-{
- struct xps2data *drvdata = platform_get_drvdata(of_dev);
- struct resource r_mem; /* IO mem resources */
-
- serio_unregister_port(drvdata->serio);
- iounmap(drvdata->base_address);
-
- /* Get iospace of the device */
- if (of_address_to_resource(of_dev->dev.of_node, 0, &r_mem))
- dev_err(drvdata->dev, "invalid address\n");
- else
- release_mem_region(r_mem.start, resource_size(&r_mem));
-
- kfree(drvdata);
-}
-
-/* Match table for of_platform binding */
-static const struct of_device_id xps2_of_match[] = {
- { .compatible = "xlnx,xps-ps2-1.00.a", },
- { /* end of list */ },
-};
-MODULE_DEVICE_TABLE(of, xps2_of_match);
-
-static struct platform_driver xps2_of_driver = {
- .driver = {
- .name = DRIVER_NAME,
- .of_match_table = xps2_of_match,
- },
- .probe = xps2_of_probe,
- .remove = xps2_of_remove,
-};
-module_platform_driver(xps2_of_driver);
-
-MODULE_AUTHOR("Xilinx, Inc.");
-MODULE_DESCRIPTION("Xilinx XPS PS/2 driver");
-MODULE_LICENSE("GPL");
-
projects / thirdparty / linux.git / commitdiff
