--- /dev/null
+/*
+ * PXA930 track ball mouse driver
+ *
+ * Copyright (C) 2007 Marvell International Ltd.
+ * 2008-02-28: Yong Yao <yaoyong@marvell.com>
+ * initial version
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+#include <mach/hardware.h>
+#include <linux/platform_data/mouse-pxa930_trkball.h>
+
+/* Trackball Controller Register Definitions */
+#define TBCR (0x000C)
+#define TBCNTR (0x0010)
+#define TBSBC (0x0014)
+
+#define TBCR_TBRST (1 << 1)
+#define TBCR_TBSB (1 << 10)
+
+#define TBCR_Y_FLT(n) (((n) & 0xf) << 6)
+#define TBCR_X_FLT(n) (((n) & 0xf) << 2)
+
+#define TBCNTR_YM(n) (((n) >> 24) & 0xff)
+#define TBCNTR_YP(n) (((n) >> 16) & 0xff)
+#define TBCNTR_XM(n) (((n) >> 8) & 0xff)
+#define TBCNTR_XP(n) ((n) & 0xff)
+
+#define TBSBC_TBSBC (0x1)
+
+struct pxa930_trkball {
+ struct pxa930_trkball_platform_data *pdata;
+
+ /* Memory Mapped Register */
+ struct resource *mem;
+ void __iomem *mmio_base;
+
+ struct input_dev *input;
+};
+
+static irqreturn_t pxa930_trkball_interrupt(int irq, void *dev_id)
+{
+ struct pxa930_trkball *trkball = dev_id;
+ struct input_dev *input = trkball->input;
+ int tbcntr, x, y;
+
+ /* According to the spec software must read TBCNTR twice:
+ * if the read value is the same, the reading is valid
+ */
+ tbcntr = __raw_readl(trkball->mmio_base + TBCNTR);
+
+ if (tbcntr == __raw_readl(trkball->mmio_base + TBCNTR)) {
+ x = (TBCNTR_XP(tbcntr) - TBCNTR_XM(tbcntr)) / 2;
+ y = (TBCNTR_YP(tbcntr) - TBCNTR_YM(tbcntr)) / 2;
+
+ input_report_rel(input, REL_X, x);
+ input_report_rel(input, REL_Y, y);
+ input_sync(input);
+ }
+
+ __raw_writel(TBSBC_TBSBC, trkball->mmio_base + TBSBC);
+ __raw_writel(0, trkball->mmio_base + TBSBC);
+
+ return IRQ_HANDLED;
+}
+
+/* For TBCR, we need to wait for a while to make sure it has been modified. */
+static int write_tbcr(struct pxa930_trkball *trkball, int v)
+{
+ int i = 100;
+
+ __raw_writel(v, trkball->mmio_base + TBCR);
+
+ while (--i) {
+ if (__raw_readl(trkball->mmio_base + TBCR) == v)
+ break;
+ msleep(1);
+ }
+
+ if (i == 0) {
+ pr_err("%s: timed out writing TBCR(%x)!\n", __func__, v);
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+static void pxa930_trkball_config(struct pxa930_trkball *trkball)
+{
+ uint32_t tbcr;
+
+ /* According to spec, need to write the filters of x,y to 0xf first! */
+ tbcr = __raw_readl(trkball->mmio_base + TBCR);
+ write_tbcr(trkball, tbcr | TBCR_X_FLT(0xf) | TBCR_Y_FLT(0xf));
+ write_tbcr(trkball, TBCR_X_FLT(trkball->pdata->x_filter) |
+ TBCR_Y_FLT(trkball->pdata->y_filter));
+
+ /* According to spec, set TBCR_TBRST first, before clearing it! */
+ tbcr = __raw_readl(trkball->mmio_base + TBCR);
+ write_tbcr(trkball, tbcr | TBCR_TBRST);
+ write_tbcr(trkball, tbcr & ~TBCR_TBRST);
+
+ __raw_writel(TBSBC_TBSBC, trkball->mmio_base + TBSBC);
+ __raw_writel(0, trkball->mmio_base + TBSBC);
+
+ pr_debug("%s: final TBCR=%x!\n", __func__,
+ __raw_readl(trkball->mmio_base + TBCR));
+}
+
+static int pxa930_trkball_open(struct input_dev *dev)
+{
+ struct pxa930_trkball *trkball = input_get_drvdata(dev);
+
+ pxa930_trkball_config(trkball);
+
+ return 0;
+}
+
+static void pxa930_trkball_disable(struct pxa930_trkball *trkball)
+{
+ uint32_t tbcr = __raw_readl(trkball->mmio_base + TBCR);
+
+ /* Held in reset, gate the 32-KHz input clock off */
+ write_tbcr(trkball, tbcr | TBCR_TBRST);
+}
+
+static void pxa930_trkball_close(struct input_dev *dev)
+{
+ struct pxa930_trkball *trkball = input_get_drvdata(dev);
+
+ pxa930_trkball_disable(trkball);
+}
+
+static int pxa930_trkball_probe(struct platform_device *pdev)
+{
+ struct pxa930_trkball *trkball;
+ struct input_dev *input;
+ struct resource *res;
+ int irq, error;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "failed to get trkball irq\n");
+ return -ENXIO;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "failed to get register memory\n");
+ return -ENXIO;
+ }
+
+ trkball = kzalloc(sizeof(struct pxa930_trkball), GFP_KERNEL);
+ if (!trkball)
+ return -ENOMEM;
+
+ trkball->pdata = dev_get_platdata(&pdev->dev);
+ if (!trkball->pdata) {
+ dev_err(&pdev->dev, "no platform data defined\n");
+ error = -EINVAL;
+ goto failed;
+ }
+
+ trkball->mmio_base = ioremap_nocache(res->start, resource_size(res));
+ if (!trkball->mmio_base) {
+ dev_err(&pdev->dev, "failed to ioremap registers\n");
+ error = -ENXIO;
+ goto failed;
+ }
+
+ /* held the module in reset, will be enabled in open() */
+ pxa930_trkball_disable(trkball);
+
+ error = request_irq(irq, pxa930_trkball_interrupt, 0,
+ pdev->name, trkball);
+ if (error) {
+ dev_err(&pdev->dev, "failed to request irq: %d\n", error);
+ goto failed_free_io;
+ }
+
+ platform_set_drvdata(pdev, trkball);
+
+ input = input_allocate_device();
+ if (!input) {
+ dev_err(&pdev->dev, "failed to allocate input device\n");
+ error = -ENOMEM;
+ goto failed_free_irq;
+ }
+
+ input->name = pdev->name;
+ input->id.bustype = BUS_HOST;
+ input->open = pxa930_trkball_open;
+ input->close = pxa930_trkball_close;
+ input->dev.parent = &pdev->dev;
+ input_set_drvdata(input, trkball);
+
+ trkball->input = input;
+
+ input_set_capability(input, EV_REL, REL_X);
+ input_set_capability(input, EV_REL, REL_Y);
+
+ error = input_register_device(input);
+ if (error) {
+ dev_err(&pdev->dev, "unable to register input device\n");
+ goto failed_free_input;
+ }
+
+ return 0;
+
+failed_free_input:
+ input_free_device(input);
+failed_free_irq:
+ free_irq(irq, trkball);
+failed_free_io:
+ iounmap(trkball->mmio_base);
+failed:
+ kfree(trkball);
+ return error;
+}
+
+static int pxa930_trkball_remove(struct platform_device *pdev)
+{
+ struct pxa930_trkball *trkball = platform_get_drvdata(pdev);
+ int irq = platform_get_irq(pdev, 0);
+
+ input_unregister_device(trkball->input);
+ free_irq(irq, trkball);
+ iounmap(trkball->mmio_base);
+ kfree(trkball);
+
+ return 0;
+}
+
+static struct platform_driver pxa930_trkball_driver = {
+ .driver = {
+ .name = "pxa930-trkball",
+ },
+ .probe = pxa930_trkball_probe,
+ .remove = pxa930_trkball_remove,
+};
+module_platform_driver(pxa930_trkball_driver);
+
+MODULE_AUTHOR("Yong Yao <yaoyong@marvell.com>");
+MODULE_DESCRIPTION("PXA930 Trackball Mouse Driver");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff