--- /dev/null
+// 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 (!priv->reg_base) {
+ err = -EINVAL;
+ 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);
git.samba.org / sfrench / cifs-2.6.git / commitdiff