diff options
Diffstat (limited to 'drivers/input/joystick/n64joy.c')
| -rw-r--r-- | drivers/input/joystick/n64joy.c | 345 |
1 files changed, 345 insertions, 0 deletions
diff --git a/drivers/input/joystick/n64joy.c b/drivers/input/joystick/n64joy.c new file mode 100644 index 000000000..9dbca3666 --- /dev/null +++ b/drivers/input/joystick/n64joy.c @@ -0,0 +1,345 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Support for the four N64 controllers. + * + * Copyright (c) 2021 Lauri Kasanen + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/input.h> +#include <linux/limits.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/timer.h> + +MODULE_AUTHOR("Lauri Kasanen <cand@gmx.com>"); +MODULE_DESCRIPTION("Driver for N64 controllers"); +MODULE_LICENSE("GPL"); + +#define PIF_RAM 0x1fc007c0 + +#define SI_DRAM_REG 0 +#define SI_READ_REG 1 +#define SI_WRITE_REG 4 +#define SI_STATUS_REG 6 + +#define SI_STATUS_DMA_BUSY BIT(0) +#define SI_STATUS_IO_BUSY BIT(1) + +#define N64_CONTROLLER_ID 0x0500 + +#define MAX_CONTROLLERS 4 + +static const char *n64joy_phys[MAX_CONTROLLERS] = { + "n64joy/port0", + "n64joy/port1", + "n64joy/port2", + "n64joy/port3", +}; + +struct n64joy_priv { + u64 si_buf[8] ____cacheline_aligned; + struct timer_list timer; + struct mutex n64joy_mutex; + struct input_dev *n64joy_dev[MAX_CONTROLLERS]; + u32 __iomem *reg_base; + u8 n64joy_opened; +}; + +struct joydata { + unsigned int: 16; /* unused */ + unsigned int err: 2; + unsigned int: 14; /* unused */ + + union { + u32 data; + + struct { + unsigned int a: 1; + unsigned int b: 1; + unsigned int z: 1; + unsigned int start: 1; + unsigned int up: 1; + unsigned int down: 1; + unsigned int left: 1; + unsigned int right: 1; + unsigned int: 2; /* unused */ + unsigned int l: 1; + unsigned int r: 1; + unsigned int c_up: 1; + unsigned int c_down: 1; + unsigned int c_left: 1; + unsigned int c_right: 1; + signed int x: 8; + signed int y: 8; + }; + }; +}; + +static void n64joy_write_reg(u32 __iomem *reg_base, const u8 reg, const u32 value) +{ + writel(value, reg_base + reg); +} + +static u32 n64joy_read_reg(u32 __iomem *reg_base, const u8 reg) +{ + return readl(reg_base + reg); +} + +static void n64joy_wait_si_dma(u32 __iomem *reg_base) +{ + while (n64joy_read_reg(reg_base, SI_STATUS_REG) & + (SI_STATUS_DMA_BUSY | SI_STATUS_IO_BUSY)) + cpu_relax(); +} + +static void n64joy_exec_pif(struct n64joy_priv *priv, const u64 in[8]) +{ + unsigned long flags; + + dma_cache_wback_inv((unsigned long) in, 8 * 8); + dma_cache_inv((unsigned long) priv->si_buf, 8 * 8); + + local_irq_save(flags); + + n64joy_wait_si_dma(priv->reg_base); + + barrier(); + n64joy_write_reg(priv->reg_base, SI_DRAM_REG, virt_to_phys(in)); + barrier(); + n64joy_write_reg(priv->reg_base, SI_WRITE_REG, PIF_RAM); + barrier(); + + n64joy_wait_si_dma(priv->reg_base); + + barrier(); + n64joy_write_reg(priv->reg_base, SI_DRAM_REG, virt_to_phys(priv->si_buf)); + barrier(); + n64joy_write_reg(priv->reg_base, SI_READ_REG, PIF_RAM); + barrier(); + + n64joy_wait_si_dma(priv->reg_base); + + local_irq_restore(flags); +} + +static const u64 polldata[] ____cacheline_aligned = { + 0xff010401ffffffff, + 0xff010401ffffffff, + 0xff010401ffffffff, + 0xff010401ffffffff, + 0xfe00000000000000, + 0, + 0, + 1 +}; + +static void n64joy_poll(struct timer_list *t) +{ + const struct joydata *data; + struct n64joy_priv *priv = container_of(t, struct n64joy_priv, timer); + struct input_dev *dev; + u32 i; + + n64joy_exec_pif(priv, polldata); + + data = (struct joydata *) priv->si_buf; + + for (i = 0; i < MAX_CONTROLLERS; i++) { + if (!priv->n64joy_dev[i]) + continue; + + dev = priv->n64joy_dev[i]; + + /* d-pad */ + input_report_key(dev, BTN_DPAD_UP, data[i].up); + input_report_key(dev, BTN_DPAD_DOWN, data[i].down); + input_report_key(dev, BTN_DPAD_LEFT, data[i].left); + input_report_key(dev, BTN_DPAD_RIGHT, data[i].right); + + /* c buttons */ + input_report_key(dev, BTN_FORWARD, data[i].c_up); + input_report_key(dev, BTN_BACK, data[i].c_down); + input_report_key(dev, BTN_LEFT, data[i].c_left); + input_report_key(dev, BTN_RIGHT, data[i].c_right); + + /* matching buttons */ + input_report_key(dev, BTN_START, data[i].start); + input_report_key(dev, BTN_Z, data[i].z); + + /* remaining ones: a, b, l, r */ + input_report_key(dev, BTN_0, data[i].a); + input_report_key(dev, BTN_1, data[i].b); + input_report_key(dev, BTN_2, data[i].l); + input_report_key(dev, BTN_3, data[i].r); + + input_report_abs(dev, ABS_X, data[i].x); + input_report_abs(dev, ABS_Y, data[i].y); + + input_sync(dev); + } + + mod_timer(&priv->timer, jiffies + msecs_to_jiffies(16)); +} + +static int n64joy_open(struct input_dev *dev) +{ + struct n64joy_priv *priv = input_get_drvdata(dev); + int err; + + err = mutex_lock_interruptible(&priv->n64joy_mutex); + if (err) + return err; + + if (!priv->n64joy_opened) { + /* + * We could use the vblank irq, but it's not important if + * the poll point slightly changes. + */ + timer_setup(&priv->timer, n64joy_poll, 0); + mod_timer(&priv->timer, jiffies + msecs_to_jiffies(16)); + } + + priv->n64joy_opened++; + + mutex_unlock(&priv->n64joy_mutex); + return err; +} + +static void n64joy_close(struct input_dev *dev) +{ + struct n64joy_priv *priv = input_get_drvdata(dev); + + mutex_lock(&priv->n64joy_mutex); + if (!--priv->n64joy_opened) + del_timer_sync(&priv->timer); + mutex_unlock(&priv->n64joy_mutex); +} + +static const u64 __initconst scandata[] ____cacheline_aligned = { + 0xff010300ffffffff, + 0xff010300ffffffff, + 0xff010300ffffffff, + 0xff010300ffffffff, + 0xfe00000000000000, + 0, + 0, + 1 +}; + +/* + * The target device is embedded and RAM-constrained. We save RAM + * by initializing in __init code that gets dropped late in boot. + * For the same reason there is no module or unloading support. + */ +static int __init n64joy_probe(struct platform_device *pdev) +{ + const struct joydata *data; + struct n64joy_priv *priv; + struct input_dev *dev; + int err = 0; + u32 i, j, found = 0; + + priv = kzalloc(sizeof(struct n64joy_priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + mutex_init(&priv->n64joy_mutex); + + priv->reg_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->reg_base)) { + err = PTR_ERR(priv->reg_base); + goto fail; + } + + /* The controllers are not hotpluggable, so we can scan in init */ + n64joy_exec_pif(priv, scandata); + + data = (struct joydata *) priv->si_buf; + + for (i = 0; i < MAX_CONTROLLERS; i++) { + if (!data[i].err && data[i].data >> 16 == N64_CONTROLLER_ID) { + found++; + + dev = priv->n64joy_dev[i] = input_allocate_device(); + if (!priv->n64joy_dev[i]) { + err = -ENOMEM; + goto fail; + } + + input_set_drvdata(dev, priv); + + dev->name = "N64 controller"; + dev->phys = n64joy_phys[i]; + dev->id.bustype = BUS_HOST; + dev->id.vendor = 0; + dev->id.product = data[i].data >> 16; + dev->id.version = 0; + dev->dev.parent = &pdev->dev; + + dev->open = n64joy_open; + dev->close = n64joy_close; + + /* d-pad */ + input_set_capability(dev, EV_KEY, BTN_DPAD_UP); + input_set_capability(dev, EV_KEY, BTN_DPAD_DOWN); + input_set_capability(dev, EV_KEY, BTN_DPAD_LEFT); + input_set_capability(dev, EV_KEY, BTN_DPAD_RIGHT); + /* c buttons */ + input_set_capability(dev, EV_KEY, BTN_LEFT); + input_set_capability(dev, EV_KEY, BTN_RIGHT); + input_set_capability(dev, EV_KEY, BTN_FORWARD); + input_set_capability(dev, EV_KEY, BTN_BACK); + /* matching buttons */ + input_set_capability(dev, EV_KEY, BTN_START); + input_set_capability(dev, EV_KEY, BTN_Z); + /* remaining ones: a, b, l, r */ + input_set_capability(dev, EV_KEY, BTN_0); + input_set_capability(dev, EV_KEY, BTN_1); + input_set_capability(dev, EV_KEY, BTN_2); + input_set_capability(dev, EV_KEY, BTN_3); + + for (j = 0; j < 2; j++) + input_set_abs_params(dev, ABS_X + j, + S8_MIN, S8_MAX, 0, 0); + + err = input_register_device(dev); + if (err) { + input_free_device(dev); + goto fail; + } + } + } + + pr_info("%u controller(s) connected\n", found); + + if (!found) + return -ENODEV; + + return 0; +fail: + for (i = 0; i < MAX_CONTROLLERS; i++) { + if (!priv->n64joy_dev[i]) + continue; + input_unregister_device(priv->n64joy_dev[i]); + } + return err; +} + +static struct platform_driver n64joy_driver = { + .driver = { + .name = "n64joy", + }, +}; + +static int __init n64joy_init(void) +{ + return platform_driver_probe(&n64joy_driver, n64joy_probe); +} + +module_init(n64joy_init); |