diff options
Diffstat (limited to 'drivers/input/serio/ambakmi.c')
| -rw-r--r-- | drivers/input/serio/ambakmi.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/drivers/input/serio/ambakmi.c b/drivers/input/serio/ambakmi.c new file mode 100644 index 000000000..c391700fc --- /dev/null +++ b/drivers/input/serio/ambakmi.c @@ -0,0 +1,210 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * linux/drivers/input/serio/ambakmi.c + * + * Copyright (C) 2000-2003 Deep Blue Solutions Ltd. + * Copyright (C) 2002 Russell King. + */ +#include <linux/module.h> +#include <linux/serio.h> +#include <linux/errno.h> +#include <linux/interrupt.h> +#include <linux/ioport.h> +#include <linux/device.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/amba/bus.h> +#include <linux/amba/kmi.h> +#include <linux/clk.h> + +#include <asm/io.h> +#include <asm/irq.h> + +#define KMI_BASE (kmi->base) + +struct amba_kmi_port { + struct serio *io; + struct clk *clk; + void __iomem *base; + unsigned int irq; + unsigned int divisor; + unsigned int open; +}; + +static irqreturn_t amba_kmi_int(int irq, void *dev_id) +{ + struct amba_kmi_port *kmi = dev_id; + unsigned int status = readb(KMIIR); + int handled = IRQ_NONE; + + while (status & KMIIR_RXINTR) { + serio_interrupt(kmi->io, readb(KMIDATA), 0); + status = readb(KMIIR); + handled = IRQ_HANDLED; + } + + return handled; +} + +static int amba_kmi_write(struct serio *io, unsigned char val) +{ + struct amba_kmi_port *kmi = io->port_data; + unsigned int timeleft = 10000; /* timeout in 100ms */ + + while ((readb(KMISTAT) & KMISTAT_TXEMPTY) == 0 && --timeleft) + udelay(10); + + if (timeleft) + writeb(val, KMIDATA); + + return timeleft ? 0 : SERIO_TIMEOUT; +} + +static int amba_kmi_open(struct serio *io) +{ + struct amba_kmi_port *kmi = io->port_data; + unsigned int divisor; + int ret; + + ret = clk_prepare_enable(kmi->clk); + if (ret) + goto out; + + divisor = clk_get_rate(kmi->clk) / 8000000 - 1; + writeb(divisor, KMICLKDIV); + writeb(KMICR_EN, KMICR); + + ret = request_irq(kmi->irq, amba_kmi_int, IRQF_SHARED, "kmi-pl050", + kmi); + if (ret) { + printk(KERN_ERR "kmi: failed to claim IRQ%d\n", kmi->irq); + writeb(0, KMICR); + goto clk_disable; + } + + writeb(KMICR_EN | KMICR_RXINTREN, KMICR); + + return 0; + + clk_disable: + clk_disable_unprepare(kmi->clk); + out: + return ret; +} + +static void amba_kmi_close(struct serio *io) +{ + struct amba_kmi_port *kmi = io->port_data; + + writeb(0, KMICR); + + free_irq(kmi->irq, kmi); + clk_disable_unprepare(kmi->clk); +} + +static int amba_kmi_probe(struct amba_device *dev, + const struct amba_id *id) +{ + struct amba_kmi_port *kmi; + struct serio *io; + int ret; + + ret = amba_request_regions(dev, NULL); + if (ret) + return ret; + + kmi = kzalloc(sizeof(struct amba_kmi_port), GFP_KERNEL); + io = kzalloc(sizeof(struct serio), GFP_KERNEL); + if (!kmi || !io) { + ret = -ENOMEM; + goto out; + } + + + io->id.type = SERIO_8042; + io->write = amba_kmi_write; + io->open = amba_kmi_open; + io->close = amba_kmi_close; + strscpy(io->name, dev_name(&dev->dev), sizeof(io->name)); + strscpy(io->phys, dev_name(&dev->dev), sizeof(io->phys)); + io->port_data = kmi; + io->dev.parent = &dev->dev; + + kmi->io = io; + kmi->base = ioremap(dev->res.start, resource_size(&dev->res)); + if (!kmi->base) { + ret = -ENOMEM; + goto out; + } + + kmi->clk = clk_get(&dev->dev, "KMIREFCLK"); + if (IS_ERR(kmi->clk)) { + ret = PTR_ERR(kmi->clk); + goto unmap; + } + + kmi->irq = dev->irq[0]; + amba_set_drvdata(dev, kmi); + + serio_register_port(kmi->io); + return 0; + + unmap: + iounmap(kmi->base); + out: + kfree(kmi); + kfree(io); + amba_release_regions(dev); + return ret; +} + +static void amba_kmi_remove(struct amba_device *dev) +{ + struct amba_kmi_port *kmi = amba_get_drvdata(dev); + + serio_unregister_port(kmi->io); + clk_put(kmi->clk); + iounmap(kmi->base); + kfree(kmi); + amba_release_regions(dev); +} + +static int __maybe_unused amba_kmi_resume(struct device *dev) +{ + struct amba_kmi_port *kmi = dev_get_drvdata(dev); + + /* kick the serio layer to rescan this port */ + serio_reconnect(kmi->io); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(amba_kmi_dev_pm_ops, NULL, amba_kmi_resume); + +static const struct amba_id amba_kmi_idtable[] = { + { + .id = 0x00041050, + .mask = 0x000fffff, + }, + { 0, 0 } +}; + +MODULE_DEVICE_TABLE(amba, amba_kmi_idtable); + +static struct amba_driver ambakmi_driver = { + .drv = { + .name = "kmi-pl050", + .owner = THIS_MODULE, + .pm = &amba_kmi_dev_pm_ops, + }, + .id_table = amba_kmi_idtable, + .probe = amba_kmi_probe, + .remove = amba_kmi_remove, +}; + +module_amba_driver(ambakmi_driver); + +MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>"); +MODULE_DESCRIPTION("AMBA KMI controller driver"); +MODULE_LICENSE("GPL"); |