// SPDX-License-Identifier: GPL-2.0-only

  /*
   * Simple USB RGB LED driver
   *
   * Copyright 2016 Heiner Kallweit <hkallweit1@gmail.com>
   * Based on drivers/hid/hid-thingm.c and
   * drivers/usb/misc/usbled.c

   */
  
  #include <linux/hid.h>
  #include <linux/hidraw.h>
  #include <linux/leds.h>
  #include <linux/module.h>
  #include <linux/mutex.h>
  
  #include "hid-ids.h"
  
  enum hidled_report_type {
  	RAW_REQUEST,
  	OUTPUT_REPORT
  };
  
  enum hidled_type {
  	RISO_KAGAKU,
  	DREAM_CHEEKY,

  	THINGM,

  	DELCOM,

  	LUXAFOR,

  };
  
  static unsigned const char riso_kagaku_tbl[] = {
  /* R+2G+4B -> riso kagaku color index */
  	[0] = 0, /* black   */
  	[1] = 2, /* red     */
  	[2] = 1, /* green   */
  	[3] = 5, /* yellow  */
  	[4] = 3, /* blue    */
  	[5] = 6, /* magenta */
  	[6] = 4, /* cyan    */
  	[7] = 7  /* white   */
  };
  
  #define RISO_KAGAKU_IX(r, g, b) riso_kagaku_tbl[((r)?1:0)+((g)?2:0)+((b)?4:0)]

  union delcom_packet {
  	__u8 data[8];
  	struct {
  		__u8 major_cmd;
  		__u8 minor_cmd;
  		__u8 data_lsb;
  		__u8 data_msb;
  	} tx;
  	struct {
  		__u8 cmd;
  	} rx;
  	struct {
  		__le16 family_code;
  		__le16 security_code;
  		__u8 fw_version;
  	} fw;
  };
  
  #define DELCOM_GREEN_LED	0
  #define DELCOM_RED_LED		1
  #define DELCOM_BLUE_LED		2

  struct hidled_device;

  struct hidled_rgb;

  
  struct hidled_config {
  	enum hidled_type	type;
  	const char		*name;
  	const char		*short_name;
  	enum led_brightness	max_brightness;

  	int			num_leds;

  	size_t			report_size;
  	enum hidled_report_type	report_type;

  	int (*init)(struct hidled_device *ldev);
  	int (*write)(struct led_classdev *cdev, enum led_brightness br);
  };
  
  struct hidled_led {
  	struct led_classdev	cdev;

  	struct hidled_rgb	*rgb;

  	char			name[32];
  };

  struct hidled_rgb {
  	struct hidled_device	*ldev;

  	struct hidled_led	red;
  	struct hidled_led	green;
  	struct hidled_led	blue;

  	u8			num;
  };
  
  struct hidled_device {
  	const struct hidled_config *config;

  	struct hid_device       *hdev;

  	struct hidled_rgb	*rgb;

  	u8			*buf;

  	struct mutex		lock;
  };
  
  #define MAX_REPORT_SIZE		16
  
  #define to_hidled_led(arg) container_of(arg, struct hidled_led, cdev)
  
  static bool riso_kagaku_switch_green_blue;
  module_param(riso_kagaku_switch_green_blue, bool, S_IRUGO | S_IWUSR);
  MODULE_PARM_DESC(riso_kagaku_switch_green_blue,
  	"switch green and blue RGB component for Riso Kagaku devices");
  
  static int hidled_send(struct hidled_device *ldev, __u8 *buf)
  {
  	int ret;

  	mutex_lock(&ldev->lock);

  	/*
  	 * buffer provided to hid_hw_raw_request must not be on the stack
  	 * and must not be part of a data structure
  	 */
  	memcpy(ldev->buf, buf, ldev->config->report_size);

  	if (ldev->config->report_type == RAW_REQUEST)

  		ret = hid_hw_raw_request(ldev->hdev, buf[0], ldev->buf,

  					 ldev->config->report_size,
  					 HID_FEATURE_REPORT,
  					 HID_REQ_SET_REPORT);
  	else if (ldev->config->report_type == OUTPUT_REPORT)

  		ret = hid_hw_output_report(ldev->hdev, ldev->buf,

  					   ldev->config->report_size);
  	else
  		ret = -EINVAL;
  
  	mutex_unlock(&ldev->lock);
  
  	if (ret < 0)
  		return ret;
  
  	return ret == ldev->config->report_size ? 0 : -EMSGSIZE;
  }

  /* reading data is supported for report type RAW_REQUEST only */
  static int hidled_recv(struct hidled_device *ldev, __u8 *buf)
  {
  	int ret;
  
  	if (ldev->config->report_type != RAW_REQUEST)
  		return -EINVAL;

  	mutex_lock(&ldev->lock);

  	memcpy(ldev->buf, buf, ldev->config->report_size);
  
  	ret = hid_hw_raw_request(ldev->hdev, buf[0], ldev->buf,

  				 ldev->config->report_size,
  				 HID_FEATURE_REPORT,
  				 HID_REQ_SET_REPORT);
  	if (ret < 0)
  		goto err;

  	ret = hid_hw_raw_request(ldev->hdev, buf[0], ldev->buf,

  				 ldev->config->report_size,
  				 HID_FEATURE_REPORT,
  				 HID_REQ_GET_REPORT);

  
  	memcpy(buf, ldev->buf, ldev->config->report_size);

  err:
  	mutex_unlock(&ldev->lock);
  
  	return ret < 0 ? ret : 0;
  }

  static u8 riso_kagaku_index(struct hidled_rgb *rgb)

  {
  	enum led_brightness r, g, b;

  	r = rgb->red.cdev.brightness;
  	g = rgb->green.cdev.brightness;
  	b = rgb->blue.cdev.brightness;

  
  	if (riso_kagaku_switch_green_blue)
  		return RISO_KAGAKU_IX(r, b, g);
  	else
  		return RISO_KAGAKU_IX(r, g, b);
  }
  
  static int riso_kagaku_write(struct led_classdev *cdev, enum led_brightness br)
  {
  	struct hidled_led *led = to_hidled_led(cdev);

  	struct hidled_rgb *rgb = led->rgb;

  	__u8 buf[MAX_REPORT_SIZE] = {};

  	buf[1] = riso_kagaku_index(rgb);

  	return hidled_send(rgb->ldev, buf);

  }
  
  static int dream_cheeky_write(struct led_classdev *cdev, enum led_brightness br)
  {
  	struct hidled_led *led = to_hidled_led(cdev);

  	struct hidled_rgb *rgb = led->rgb;

  	__u8 buf[MAX_REPORT_SIZE] = {};

  	buf[1] = rgb->red.cdev.brightness;
  	buf[2] = rgb->green.cdev.brightness;
  	buf[3] = rgb->blue.cdev.brightness;

  	buf[7] = 0x1a;
  	buf[8] = 0x05;

  	return hidled_send(rgb->ldev, buf);

  }
  
  static int dream_cheeky_init(struct hidled_device *ldev)
  {
  	__u8 buf[MAX_REPORT_SIZE] = {};
  
  	/* Dream Cheeky magic */
  	buf[1] = 0x1f;
  	buf[2] = 0x02;
  	buf[4] = 0x5f;
  	buf[7] = 0x1a;
  	buf[8] = 0x03;
  
  	return hidled_send(ldev, buf);
  }

  static int _thingm_write(struct led_classdev *cdev, enum led_brightness br,
  			 u8 offset)
  {
  	struct hidled_led *led = to_hidled_led(cdev);

  	__u8 buf[MAX_REPORT_SIZE] = { 1, 'c' };

  
  	buf[2] = led->rgb->red.cdev.brightness;
  	buf[3] = led->rgb->green.cdev.brightness;
  	buf[4] = led->rgb->blue.cdev.brightness;
  	buf[7] = led->rgb->num + offset;
  
  	return hidled_send(led->rgb->ldev, buf);
  }
  
  static int thingm_write_v1(struct led_classdev *cdev, enum led_brightness br)
  {
  	return _thingm_write(cdev, br, 0);
  }
  
  static int thingm_write(struct led_classdev *cdev, enum led_brightness br)
  {
  	return _thingm_write(cdev, br, 1);
  }
  
  static const struct hidled_config hidled_config_thingm_v1 = {
  	.name = "ThingM blink(1) v1",
  	.short_name = "thingm",
  	.max_brightness = 255,
  	.num_leds = 1,
  	.report_size = 9,
  	.report_type = RAW_REQUEST,

  	.write = thingm_write_v1,
  };
  
  static int thingm_init(struct hidled_device *ldev)
  {

  	__u8 buf[MAX_REPORT_SIZE] = { 1, 'v' };

  	int ret;
  
  	ret = hidled_recv(ldev, buf);
  	if (ret)
  		return ret;
  
  	/* Check for firmware major version 1 */
  	if (buf[3] == '1')
  		ldev->config = &hidled_config_thingm_v1;
  
  	return 0;
  }

  static inline int delcom_get_lednum(const struct hidled_led *led)
  {
  	if (led == &led->rgb->red)
  		return DELCOM_RED_LED;
  	else if (led == &led->rgb->green)
  		return DELCOM_GREEN_LED;
  	else
  		return DELCOM_BLUE_LED;
  }
  
  static int delcom_enable_led(struct hidled_led *led)
  {
  	union delcom_packet dp = { .tx.major_cmd = 101, .tx.minor_cmd = 12 };
  
  	dp.tx.data_lsb = 1 << delcom_get_lednum(led);
  	dp.tx.data_msb = 0;
  
  	return hidled_send(led->rgb->ldev, dp.data);
  }
  
  static int delcom_set_pwm(struct hidled_led *led)
  {
  	union delcom_packet dp = { .tx.major_cmd = 101, .tx.minor_cmd = 34 };
  
  	dp.tx.data_lsb = delcom_get_lednum(led);
  	dp.tx.data_msb = led->cdev.brightness;
  
  	return hidled_send(led->rgb->ldev, dp.data);
  }
  
  static int delcom_write(struct led_classdev *cdev, enum led_brightness br)
  {
  	struct hidled_led *led = to_hidled_led(cdev);
  	int ret;
  
  	/*
  	 * enable LED
  	 * We can't do this in the init function already because the device
  	 * is internally reset later.
  	 */
  	ret = delcom_enable_led(led);
  	if (ret)
  		return ret;
  
  	return delcom_set_pwm(led);
  }
  
  static int delcom_init(struct hidled_device *ldev)
  {
  	union delcom_packet dp = { .rx.cmd = 104 };
  	int ret;
  
  	ret = hidled_recv(ldev, dp.data);
  	if (ret)
  		return ret;
  	/*
  	 * Several Delcom devices share the same USB VID/PID
  	 * Check for family id 2 for Visual Signal Indicator
  	 */

  	return le16_to_cpu(dp.fw.family_code) == 2 ? 0 : -ENODEV;

  }

  static int luxafor_write(struct led_classdev *cdev, enum led_brightness br)
  {
  	struct hidled_led *led = to_hidled_led(cdev);
  	__u8 buf[MAX_REPORT_SIZE] = { [1] = 1 };
  
  	buf[2] = led->rgb->num + 1;
  	buf[3] = led->rgb->red.cdev.brightness;
  	buf[4] = led->rgb->green.cdev.brightness;
  	buf[5] = led->rgb->blue.cdev.brightness;
  
  	return hidled_send(led->rgb->ldev, buf);
  }

  static const struct hidled_config hidled_configs[] = {
  	{
  		.type = RISO_KAGAKU,
  		.name = "Riso Kagaku Webmail Notifier",
  		.short_name = "riso_kagaku",
  		.max_brightness = 1,

  		.num_leds = 1,

  		.report_size = 6,
  		.report_type = OUTPUT_REPORT,

  		.write = riso_kagaku_write,
  	},
  	{
  		.type = DREAM_CHEEKY,
  		.name = "Dream Cheeky Webmail Notifier",
  		.short_name = "dream_cheeky",
  		.max_brightness = 31,

  		.num_leds = 1,

  		.report_size = 9,
  		.report_type = RAW_REQUEST,

  		.init = dream_cheeky_init,
  		.write = dream_cheeky_write,
  	},

  	{
  		.type = THINGM,
  		.name = "ThingM blink(1)",
  		.short_name = "thingm",
  		.max_brightness = 255,
  		.num_leds = 2,
  		.report_size = 9,
  		.report_type = RAW_REQUEST,

  		.init = thingm_init,
  		.write = thingm_write,
  	},

  	{
  		.type = DELCOM,
  		.name = "Delcom Visual Signal Indicator G2",
  		.short_name = "delcom",
  		.max_brightness = 100,
  		.num_leds = 1,
  		.report_size = 8,
  		.report_type = RAW_REQUEST,
  		.init = delcom_init,
  		.write = delcom_write,
  	},

  	{
  		.type = LUXAFOR,
  		.name = "Greynut Luxafor",
  		.short_name = "luxafor",
  		.max_brightness = 255,
  		.num_leds = 6,
  		.report_size = 9,
  		.report_type = OUTPUT_REPORT,
  		.write = luxafor_write,
  	},

  };
  
  static int hidled_init_led(struct hidled_led *led, const char *color_name,

  			   struct hidled_rgb *rgb, unsigned int minor)

  {

  	const struct hidled_config *config = rgb->ldev->config;
  
  	if (config->num_leds > 1)
  		snprintf(led->name, sizeof(led->name), "%s%u:%s:led%u",
  			 config->short_name, minor, color_name, rgb->num);
  	else
  		snprintf(led->name, sizeof(led->name), "%s%u:%s",
  			 config->short_name, minor, color_name);

  	led->cdev.name = led->name;

  	led->cdev.max_brightness = config->max_brightness;
  	led->cdev.brightness_set_blocking = config->write;

  	led->cdev.flags = LED_HW_PLUGGABLE;

  	led->rgb = rgb;

  	return devm_led_classdev_register(&rgb->ldev->hdev->dev, &led->cdev);

  }

  static int hidled_init_rgb(struct hidled_rgb *rgb, unsigned int minor)

  {
  	int ret;
  
  	/* Register the red diode */

  	ret = hidled_init_led(&rgb->red, "red", rgb, minor);

  	if (ret)
  		return ret;
  
  	/* Register the green diode */

  	ret = hidled_init_led(&rgb->green, "green", rgb, minor);

  	if (ret)
  		return ret;
  
  	/* Register the blue diode */

  	return hidled_init_led(&rgb->blue, "blue", rgb, minor);

  }
  
  static int hidled_probe(struct hid_device *hdev, const struct hid_device_id *id)
  {
  	struct hidled_device *ldev;
  	unsigned int minor;
  	int ret, i;
  
  	ldev = devm_kzalloc(&hdev->dev, sizeof(*ldev), GFP_KERNEL);
  	if (!ldev)
  		return -ENOMEM;

  	ldev->buf = devm_kmalloc(&hdev->dev, MAX_REPORT_SIZE, GFP_KERNEL);
  	if (!ldev->buf)
  		return -ENOMEM;

  	ret = hid_parse(hdev);
  	if (ret)
  		return ret;
  
  	ldev->hdev = hdev;
  	mutex_init(&ldev->lock);
  
  	for (i = 0; !ldev->config && i < ARRAY_SIZE(hidled_configs); i++)
  		if (hidled_configs[i].type == id->driver_data)
  			ldev->config = &hidled_configs[i];
  
  	if (!ldev->config)
  		return -EINVAL;
  
  	if (ldev->config->init) {
  		ret = ldev->config->init(ldev);
  		if (ret)
  			return ret;
  	}

  	ldev->rgb = devm_kcalloc(&hdev->dev, ldev->config->num_leds,
  				 sizeof(struct hidled_rgb), GFP_KERNEL);
  	if (!ldev->rgb)
  		return -ENOMEM;

  	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
  	if (ret)
  		return ret;
  
  	minor = ((struct hidraw *) hdev->hidraw)->minor;

  	for (i = 0; i < ldev->config->num_leds; i++) {
  		ldev->rgb[i].ldev = ldev;
  		ldev->rgb[i].num = i;
  		ret = hidled_init_rgb(&ldev->rgb[i], minor);
  		if (ret) {
  			hid_hw_stop(hdev);
  			return ret;
  		}

  	}
  
  	hid_info(hdev, "%s initialized
  ", ldev->config->name);
  
  	return 0;
  }
  
  static const struct hid_device_id hidled_table[] = {
  	{ HID_USB_DEVICE(USB_VENDOR_ID_RISO_KAGAKU,
  	  USB_DEVICE_ID_RI_KA_WEBMAIL), .driver_data = RISO_KAGAKU },
  	{ HID_USB_DEVICE(USB_VENDOR_ID_DREAM_CHEEKY,
  	  USB_DEVICE_ID_DREAM_CHEEKY_WN), .driver_data = DREAM_CHEEKY },
  	{ HID_USB_DEVICE(USB_VENDOR_ID_DREAM_CHEEKY,
  	  USB_DEVICE_ID_DREAM_CHEEKY_FA), .driver_data = DREAM_CHEEKY },

  	{ HID_USB_DEVICE(USB_VENDOR_ID_THINGM,
  	  USB_DEVICE_ID_BLINK1), .driver_data = THINGM },

  	{ HID_USB_DEVICE(USB_VENDOR_ID_DELCOM,
  	  USB_DEVICE_ID_DELCOM_VISUAL_IND), .driver_data = DELCOM },

  	{ HID_USB_DEVICE(USB_VENDOR_ID_MICROCHIP,
  	  USB_DEVICE_ID_LUXAFOR), .driver_data = LUXAFOR },

  	{ }
  };
  MODULE_DEVICE_TABLE(hid, hidled_table);
  
  static struct hid_driver hidled_driver = {
  	.name = "hid-led",
  	.probe = hidled_probe,
  	.id_table = hidled_table,
  };
  
  module_hid_driver(hidled_driver);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Heiner Kallweit <hkallweit1@gmail.com>");
  MODULE_DESCRIPTION("Simple USB RGB LED driver");