diff options
Diffstat (limited to 'drivers/input/joystick/fsia6b.c')
-rw-r--r-- | drivers/input/joystick/fsia6b.c | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/drivers/input/joystick/fsia6b.c b/drivers/input/joystick/fsia6b.c new file mode 100644 index 0000000000..76ffdec5c1 --- /dev/null +++ b/drivers/input/joystick/fsia6b.c @@ -0,0 +1,231 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * FS-iA6B iBus RC receiver driver + * + * This driver provides all 14 channels of the FlySky FS-ia6B RC receiver + * as analog values. + * + * Additionally, the channels can be converted to discrete switch values. + * By default, it is configured for the offical FS-i6 remote control. + * If you use a different hardware configuration, you can configure it + * using the `switch_config` parameter. + */ + +#include <linux/device.h> +#include <linux/input.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/serio.h> +#include <linux/slab.h> +#include <linux/types.h> + +#define DRIVER_DESC "FS-iA6B iBus RC receiver" + +MODULE_AUTHOR("Markus Koch <markus@notsyncing.net>"); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +#define IBUS_SERVO_COUNT 14 + +static char *switch_config = "00000022320000"; +module_param(switch_config, charp, 0444); +MODULE_PARM_DESC(switch_config, + "Amount of switch positions per channel (14 characters, 0-3)"); + +static int fsia6b_axes[IBUS_SERVO_COUNT] = { + ABS_X, ABS_Y, + ABS_Z, ABS_RX, + ABS_RY, ABS_RZ, + ABS_HAT0X, ABS_HAT0Y, + ABS_HAT1X, ABS_HAT1Y, + ABS_HAT2X, ABS_HAT2Y, + ABS_HAT3X, ABS_HAT3Y +}; + +enum ibus_state { SYNC, COLLECT, PROCESS }; + +struct ibus_packet { + enum ibus_state state; + + int offset; + u16 ibuf; + u16 channel[IBUS_SERVO_COUNT]; +}; + +struct fsia6b { + struct input_dev *dev; + struct ibus_packet packet; + + char phys[32]; +}; + +static irqreturn_t fsia6b_serio_irq(struct serio *serio, + unsigned char data, unsigned int flags) +{ + struct fsia6b *fsia6b = serio_get_drvdata(serio); + int i; + int sw_state; + int sw_id = BTN_0; + + fsia6b->packet.ibuf = (data << 8) | ((fsia6b->packet.ibuf >> 8) & 0xFF); + + switch (fsia6b->packet.state) { + case SYNC: + if (fsia6b->packet.ibuf == 0x4020) + fsia6b->packet.state = COLLECT; + break; + + case COLLECT: + fsia6b->packet.state = PROCESS; + break; + + case PROCESS: + fsia6b->packet.channel[fsia6b->packet.offset] = + fsia6b->packet.ibuf; + fsia6b->packet.offset++; + + if (fsia6b->packet.offset == IBUS_SERVO_COUNT) { + fsia6b->packet.offset = 0; + fsia6b->packet.state = SYNC; + for (i = 0; i < IBUS_SERVO_COUNT; ++i) { + input_report_abs(fsia6b->dev, fsia6b_axes[i], + fsia6b->packet.channel[i]); + + sw_state = 0; + if (fsia6b->packet.channel[i] > 1900) + sw_state = 1; + else if (fsia6b->packet.channel[i] < 1100) + sw_state = 2; + + switch (switch_config[i]) { + case '3': + input_report_key(fsia6b->dev, + sw_id++, + sw_state == 0); + fallthrough; + case '2': + input_report_key(fsia6b->dev, + sw_id++, + sw_state == 1); + fallthrough; + case '1': + input_report_key(fsia6b->dev, + sw_id++, + sw_state == 2); + } + } + input_sync(fsia6b->dev); + } else { + fsia6b->packet.state = COLLECT; + } + break; + } + + return IRQ_HANDLED; +} + +static int fsia6b_serio_connect(struct serio *serio, struct serio_driver *drv) +{ + struct fsia6b *fsia6b; + struct input_dev *input_dev; + int err; + int i, j; + int sw_id = 0; + + fsia6b = kzalloc(sizeof(*fsia6b), GFP_KERNEL); + if (!fsia6b) + return -ENOMEM; + + fsia6b->packet.ibuf = 0; + fsia6b->packet.offset = 0; + fsia6b->packet.state = SYNC; + + serio_set_drvdata(serio, fsia6b); + + input_dev = input_allocate_device(); + if (!input_dev) { + err = -ENOMEM; + goto fail1; + } + fsia6b->dev = input_dev; + + snprintf(fsia6b->phys, sizeof(fsia6b->phys), "%s/input0", serio->phys); + + input_dev->name = DRIVER_DESC; + input_dev->phys = fsia6b->phys; + input_dev->id.bustype = BUS_RS232; + input_dev->id.vendor = SERIO_FSIA6B; + input_dev->id.product = serio->id.id; + input_dev->id.version = 0x0100; + input_dev->dev.parent = &serio->dev; + + for (i = 0; i < IBUS_SERVO_COUNT; i++) + input_set_abs_params(input_dev, fsia6b_axes[i], + 1000, 2000, 2, 2); + + /* Register switch configuration */ + for (i = 0; i < IBUS_SERVO_COUNT; i++) { + if (switch_config[i] < '0' || switch_config[i] > '3') { + dev_err(&fsia6b->dev->dev, + "Invalid switch configuration supplied for fsia6b.\n"); + err = -EINVAL; + goto fail2; + } + + for (j = '1'; j <= switch_config[i]; j++) { + input_set_capability(input_dev, EV_KEY, BTN_0 + sw_id); + sw_id++; + } + } + + err = serio_open(serio, drv); + if (err) + goto fail2; + + err = input_register_device(fsia6b->dev); + if (err) + goto fail3; + + return 0; + +fail3: serio_close(serio); +fail2: input_free_device(input_dev); +fail1: serio_set_drvdata(serio, NULL); + kfree(fsia6b); + return err; +} + +static void fsia6b_serio_disconnect(struct serio *serio) +{ + struct fsia6b *fsia6b = serio_get_drvdata(serio); + + serio_close(serio); + serio_set_drvdata(serio, NULL); + input_unregister_device(fsia6b->dev); + kfree(fsia6b); +} + +static const struct serio_device_id fsia6b_serio_ids[] = { + { + .type = SERIO_RS232, + .proto = SERIO_FSIA6B, + .id = SERIO_ANY, + .extra = SERIO_ANY, + }, + { 0 } +}; + +MODULE_DEVICE_TABLE(serio, fsia6b_serio_ids); + +static struct serio_driver fsia6b_serio_drv = { + .driver = { + .name = "fsia6b" + }, + .description = DRIVER_DESC, + .id_table = fsia6b_serio_ids, + .interrupt = fsia6b_serio_irq, + .connect = fsia6b_serio_connect, + .disconnect = fsia6b_serio_disconnect +}; + +module_serio_driver(fsia6b_serio_drv) |