diff options
Diffstat (limited to 'drivers/input/mouse/pxa930_trkball.c')
| -rw-r--r-- | drivers/input/mouse/pxa930_trkball.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/drivers/input/mouse/pxa930_trkball.c b/drivers/input/mouse/pxa930_trkball.c new file mode 100644 index 000000000..f04ba12db --- /dev/null +++ b/drivers/input/mouse/pxa930_trkball.c @@ -0,0 +1,250 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * PXA930 track ball mouse driver + * + * Copyright (C) 2007 Marvell International Ltd. + * 2008-02-28: Yong Yao <yaoyong@marvell.com> + * initial version + */ + +#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 <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) + 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(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"); |