#define DRIVER_VERSION  "v1.1.13"
#define DRIVER_AUTHOR   "Multi-Tech"
#define DRIVER_DESC "MTS LoRa Accessory Card"
#define DRIVER_NAME "mtac-lora"
#define DEBUG 0

#include <linux/types.h>
#include <linux/gpio.h>
#include <linux/platform_device.h>
#include <linux/kmod.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/mtac.h>
#include <linux/mts_io.h>



static struct gpio_pin gpio_pins_mtac_lora_0_0[] = {
	// gpio pins for Accessory Card 1
	{
		.name = "AP1_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap1-reset",
		},
		.do_gpio_desc = 1
	},

	// gpio pins for Accessory Card 2
	{
		.name = "AP2_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap2-reset",
		},
		.do_gpio_desc = 1
	},
	{ },
};

static struct gpio_pin gpio_pins_mtac_lora_1_5[] = {
	// gpio pins for Accessory Card 1
	{
		.name = "AP1_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap1-reset",
		},
		.do_gpio_desc = 1
	},
	{
		.name = "AP1_GPIO1",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_IN,
			.label = "ap1-cdone",
		},
		.do_gpio_desc = 1
	},
	{
		.name = "AP1_GPIO2",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap1-creset",
		},
		.do_gpio_desc = 1
	},

	// gpio pins for Accessory Card 2
	{
		.name = "AP2_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap2-reset",
		},
		.do_gpio_desc = 1
	},
	{
		.name = "AP2_GPIO1",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_IN,
			.label = "ap2-cdone",
		},
		.do_gpio_desc = 1
	},
	{
		.name = "AP2_GPIO2",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap2-creset",
		},
		.do_gpio_desc = 1
	},
	{ },
};

static struct gpio_pin gpio_pins_mtac_lora_2g4_0_0[] = {
	// gpio pins for Accessory Card 1
	{
		.name = "AP1_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap1-reset",
		},
		.do_gpio_desc = 1
	},
	{
		.name = "AP1_GPIO1",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_LOW,
			.label = "ap1-boot",
		},
		.do_gpio_desc = 1
	},

	// gpio pins for Accessory Card 2
	{
		.name = "AP2_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap2-reset",
		},
		.do_gpio_desc = 1
	},
	{
		.name = "AP2_GPIO1",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_LOW,
			.label = "ap2-boot",
		},
		.do_gpio_desc = 1
	},
	{ },
};

static struct gpio_pin gpio_pins_mtac_lora_003_0_0[] = {
	// gpio pins for Accessory Card 1
	{
		.name = "AP1_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap1-reset",
		},
		.do_gpio_desc = 1
	},

	{
		.name = "AP1_GPIO4",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap1-creset",
		},
		.do_gpio_desc = 1
	},

	{
		.name = "AP1_LBTRESET",
		.pin = {
			.gpio = ~0U, 
			.flags = GPIOD_OUT_LOW,
			.label = "ap1-lbtreset",
		},
		.do_gpio_desc = 1
	},
	
	// gpio pins for Accessory Card 2
	{
		.name = "AP2_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap2-reset",
		},
		.do_gpio_desc = 1
	},

	{
		.name = "AP2_GPIO4",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap2-creset",
		},
		.do_gpio_desc = 1
	},

	{
		.name = "AP2_LBTRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_LOW,
			.label = "ap2-lbtreset",
		},
		.do_gpio_desc = 1
	},
	
	{ },
};

static struct gpio_pin gpio_pins_mtac_lora_003_0_1[] = {
	// gpio pins for Accessory Card 1
	{
		.name = "AP1_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap1-reset",
		},
		.do_gpio_desc = 1
	},

	{
		.name = "AP1_GPIO4",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap1-creset",
		},
		.do_gpio_desc = 1
	},

	{
		.name = "AP1_TBD1",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_LOW,
			.label = "ap1-lbtreset",
		},
		.do_gpio_desc = 1
	},
	
	// gpio pins for Accessory Card 2
	{
		.name = "AP2_NRESET",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap2-reset",
		},
		.do_gpio_desc = 1
	},

	{
		.name = "AP2_GPIO4",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_HIGH,
			.label = "ap2-creset",
		},
		.do_gpio_desc = 1
	},

	{
		.name = "AP2_TBD1",
		.pin = {
			.gpio = ~0U,
			.flags = GPIOD_OUT_LOW,
			.label = "ap2-lbtreset",
		},
		.do_gpio_desc = 1
	},
	
	{ },
};

ssize_t lora_show_eui(struct kobject *kobj, struct kobj_attribute *attr, char *buf)
{
	int retval = -1;
	int port;
	int port_index;
	struct mts_ap_eeprom_layout *app;


	port = mtac_port_from_kobject(kobj);
	if (port < 1) {
		log_error("mtac_port_from_kobject returned %d", port);
		return -1;
	}
	port_index = port - 1;

	app = (struct mts_ap_eeprom_layout *)mts_ap_eeprom[port_index];
	if (! strcmp(attr->attr.name, "eui")) {
		retval = sprintf(buf, "%02X:%02X:%02X:%02X:%02X:%02X:%02X:%02X\n",
			app->eui[0],
			app->eui[1],
			app->eui[2],
			app->eui[3],
			app->eui[4],
			app->eui[5],
			app->eui[6],
			app->eui[7]);
	}
	return retval;
}


static char* lora_gpio_pin_name_by_attr_name(const char* name, int port) {
	switch (port) {
		case port_1:
			if (! strcmp(name, "reset")) {
				return "ap1-reset";
			} else if (!strcmp(name,"lbtreset")) {
				return "ap1-lbtreset";
			} else if (!strcmp(name,"nreset")) {
				return "ap1-nreset";
			} else if (!strcmp(name,"cdone")) {
				return "ap1-cdone";
			} else if (!strcmp(name,"creset")) {
				return "ap1-creset";
			} else if (!strcmp(name,"boot")) {
				return "ap1-boot";
			} else {
				log_error("attribute name [%s] is invalid for LORA in port %d", name, port);
				return "";
			}

		case port_2:
			if (! strcmp(name, "reset")) {
				return "ap2-reset";
			} else if (!strcmp(name,"lbtreset")) {
				return "ap2-lbtreset";
			} else if (!strcmp(name,"nreset")) {
				return "ap2-nreset";
			} else if (!strcmp(name,"cdone")) {
				return "ap2-cdone";
			} else if (!strcmp(name,"creset")) {
				return "ap2-creset";
			} else if (!strcmp(name,"boot")) {
				return "ap2-boot";
			} else {
				log_error("attribute name [%s] is invalid for LORA in port %d", name, port);
				return "";
			}
	}
	/* NOTREACHED */
	return "";
}

// 1 cdone/boot  (optional)
// 1 creset (optional)
// 1 eui
// 1 reset
// 1 vendor-id
// 1 product-id
// 1 device-id
// 1 hw-version
// NULL

#define ATTRS_SIZE_1_5 9
#define ATTRS_SIZE_2G4_0_0 8
#define ATTRS_SIZE_0_0 7
#define ATTRS_SIZE_003_0_0 9 /*dev*/
#define ATTRS_SIZE_003_0_1 9 /*dev*/

// Set the hardware version if the ROM string matches one of the valid
// hardware versions.
// Lengths of strings must be the same for a match, then can compare
// text.  Without a length check a subset of a string could be a match.
#define COMPARE_AND_ASSIGN(CANDIDATE) 	((hw_version_len == (sizeof(HW_VERSION_ ## CANDIDATE)-1)) && \
	  (strncmp(ap_eeprom->hw_version, HW_VERSION_ ## CANDIDATE, sizeof(HW_VERSION_ ## CANDIDATE)) == 0)) \
		lora_hw_version = CANDIDATE;

static bool lora_setup(enum ap port) {
	int i;
	int port_index = port - 1;
	int index = 0;
	int count = 0;
	int ret;
	char buf[32];
	struct kobj_attribute* attr;
	struct attribute **attrs;
	int lora_hw_version;
	int hw_version_len;
	int ap_lora_attrs_size;
	struct mts_ap_eeprom_layout *ap_eeprom;
	struct kobject *subdir;

	ap_eeprom = (struct mts_ap_eeprom_layout *)mts_ap_eeprom[port_index];

	log_info("loading LORA accessory card in port %d hw: version %s", port, ap_eeprom->hw_version);
	sprintf(buf, "ap%d", port);
	subdir = kobject_create_and_add(buf, &mts_io_platform_device->dev.kobj);
	if (! subdir) {
		log_error("kobject_create_and_add in port %d failed", port);
		return false;
	}

	// create the link to the apX directory this card is in
	// if we're in the first slot, we get plain "lora"
	// if we're in a different slot, we might need to use "lora-2" to differentiate
	if (port > 1) {
		for (i = 1; i < port; i++) {
			if (mtac_port_info[i - 1]) {
				if (strstr(mtac_port_info[i - 1]->product_id, PRODUCT_ID_MTAC_LORA)) {
					count++;
				} else if (strstr(mtac_port_info[i - 1]->product_id, PRODUCT_ID_MTAC_LORA_003)) {
					count++;
				}
			}
		}
	}
	if (count > 0) {
		sprintf(buf, "lora-%d", count + 1);
	} else {
		sprintf(buf, "lora");
	}
	log_info("sysfs_create_link called");
	ret = sysfs_create_link(subdir->parent, subdir, buf);
	if (ret) {
		log_error("failed to link [%s] to [%s], %d", buf, subdir->name, ret);
	} else
		log_debug("created link [%s] to [%s], success:%d", buf, subdir->name, ret);


	// hw_version string length, null character not counted.
	hw_version_len = strnlen(ap_eeprom->hw_version,sizeof ap_eeprom->hw_version);

	/* Set LoRa hardware version. */
	if COMPARE_AND_ASSIGN(MTAC_LORA_0_0)
	else if COMPARE_AND_ASSIGN(MTAC_LORA_1_0)
	else if COMPARE_AND_ASSIGN(MTAC_LORA_1_5)
	else if COMPARE_AND_ASSIGN(MTAC_LORA_2G4_0_0)
	else if COMPARE_AND_ASSIGN(MTAC_LORA_003_0_0)
	else if COMPARE_AND_ASSIGN(MTAC_LORA_003_0_1)
	else {
		log_error("Unknown hw-version in port %d", port);
		return false;
	}

	if ((lora_hw_version == MTAC_LORA_0_0) || (lora_hw_version == MTAC_LORA_1_0)) {
		ap_lora_attrs_size = ATTRS_SIZE_0_0;
		mtac_set_port_pins(port_index,gpio_pins_mtac_lora_0_0,subdir);
	} else if ((lora_hw_version == MTAC_LORA_2G4_0_0) || (lora_hw_version == MTAC_LORA_2G4_0_0)) {
		ap_lora_attrs_size = ATTRS_SIZE_2G4_0_0;
		mtac_set_port_pins(port_index,gpio_pins_mtac_lora_2g4_0_0,subdir);
        } else if (lora_hw_version == MTAC_LORA_003_0_0) {
                ap_lora_attrs_size = ATTRS_SIZE_003_0_0;
                mtac_set_port_pins(port_index,gpio_pins_mtac_lora_003_0_0,subdir);
	} else if (lora_hw_version == MTAC_LORA_003_0_1) {
                ap_lora_attrs_size = ATTRS_SIZE_003_0_1;
                mtac_set_port_pins(port_index,gpio_pins_mtac_lora_003_0_1,subdir);
	} else {
		ap_lora_attrs_size = ATTRS_SIZE_1_5;
		mtac_set_port_pins(port_index,gpio_pins_mtac_lora_1_5,subdir);
	}


	attrs = kzalloc(sizeof(struct attribute*) * ap_lora_attrs_size, GFP_KERNEL);
	if (! attrs) {
		log_error("failed to allocate attribute space for port %d", port);
		return false;
	}
	log_debug("Allocated %d attrs @ %p",ap_lora_attrs_size,attrs);


	sprintf(buf, "reset");
	attr = mtac_create_attribute(buf, MTS_ATTR_MODE_RW);
	if (! attr) {
		log_error("failed to create attribute [%s] for LORA in port %d", buf, port);
		kfree(attrs);
		return false;
	}
	attr->show = mtac_attr_show_ap_gpio_pin;
	attr->store = mtac_attr_store_ap_gpio_pin;
	attrs[index++] = &attr->attr;

	if (lora_hw_version == MTAC_LORA_1_5) {
		//GPIO1 - cdone on FPGA - input to CPU
		sprintf(buf, "cdone");
		attr = mtac_create_attribute(buf, MTS_ATTR_MODE_RO);
		if (! attr) {
			log_error("failed to create attribute [%s] for LORA in port %d", buf, port);
			attrs[index] = NULL;
			mtac_port_info[port_index]->attr_group.attrs = attrs;
			return false;
		}
		attr->show = mtac_attr_show_ap_gpio_pin;
		attrs[index++] = &attr->attr;

		//GPIO2 reset on FPGA - output from CPU
		sprintf(buf, "creset");
		attr = mtac_create_attribute(buf, MTS_ATTR_MODE_RW);
		if (! attr) {
			log_error("failed to create attribute [%s] for LORA in port %d", buf, port);
			attrs[index] = NULL;
			mtac_port_info[port_index]->attr_group.attrs = attrs;
	 		return false;
	 	}
		attr->show = mtac_attr_show_ap_gpio_pin;
		attr->store = mtac_attr_store_ap_gpio_pin;
		attrs[index++] = &attr->attr;
		if(index >= ap_lora_attrs_size) {
			panic("Internal error, too many attributes on the LORA card index %d >= %d",
					index,ap_lora_attrs_size);
		}
	}

	if (lora_hw_version == MTAC_LORA_2G4_0_0) {
		//GPIO1 - boot on MCU controls reset into bootloader mode
		sprintf(buf, "boot");
		attr = mtac_create_attribute(buf, MTS_ATTR_MODE_RW);
		if (! attr) {
			log_error("failed to create attribute [%s] for LORA in port %d", buf, port);
			attrs[index] = NULL;
			mtac_port_info[port_index]->attr_group.attrs = attrs;
			return false;
		}
		attr->show = mtac_attr_show_ap_gpio_pin;
		attr->store = mtac_attr_store_ap_gpio_pin;
		attrs[index++] = &attr->attr;

		if(index >= ap_lora_attrs_size) {
			panic("Internal error, too many attributes on the LORA card index %d >= %d",
					index,ap_lora_attrs_size);
		}
	}

    if (lora_hw_version == MTAC_LORA_003_0_0 || lora_hw_version == MTAC_LORA_003_0_1) {
		log_debug("assigning lbtreset");
	        //GPIO1 - boot on MCU controls reset into bootloader mode
	        sprintf(buf, "lbtreset");
	        attr = mtac_create_attribute(buf, MTS_ATTR_MODE_RW);
	        if (! attr) {
	                log_error("failed to create attribute [%s] for LORA in port %d", buf, port);
	                attrs[index] = NULL;
	                mtac_port_info[port_index]->attr_group.attrs = attrs;
	                return false;
	        }
	        attr->show = mtac_attr_show_ap_gpio_pin;
	        attr->store = mtac_attr_store_ap_gpio_pin;
	        attrs[index++] = &attr->attr;

		if(index >= ap_lora_attrs_size) {
			panic("Internal error, too many attributes on the LORA card index %d >= %d",
				index,ap_lora_attrs_size);
    		}

		log_debug("assigning creset");
	        //NRESET - Resets both the 1303 and 1261 
	        sprintf(buf, "creset");
	        attr = mtac_create_attribute(buf, MTS_ATTR_MODE_RW);
	        if (! attr) {
	                log_error("failed to create attribute [%s] for LORA in port %d", buf, port);
	                attrs[index] = NULL;
	                mtac_port_info[port_index]->attr_group.attrs = attrs;
	                return false;
	        }
	        attr->show = mtac_attr_show_ap_gpio_pin;
	        attr->store = mtac_attr_store_ap_gpio_pin;
	        attrs[index++] = &attr->attr;

		if(index >= ap_lora_attrs_size) {
			panic("Internal error, too many attributes on the LORA card index %d >= %d",
				index,ap_lora_attrs_size);
    		}
	}

	sprintf(buf,"eui");
	attr = mtac_create_attribute("eui", MTS_ATTR_MODE_RO);
	if (! attr) {
		log_error("failed to create attribute [%s] for LORA in port %d", buf, port);
		attrs[index] = NULL;
		mtac_port_info[port_index]->attr_group.attrs = attrs;
		return false;
	}
	attr->show = lora_show_eui;
	attrs[index++] = &attr->attr;

	// add attributes for eeprom contents
	ret = mtac_add_product_info_attributes(port, attrs, &index);
	log_debug("Terminate addrs at index %d",index);
	attrs[index] = NULL;  // Terminate the array.
	mtac_port_info[port_index]->attr_group.attrs = attrs;  // attrs available for teardown.

	if (!ret) {
		log_error("failed to add product info attributes for LORA in port %d", port);
		return false;
	}
        log_debug("mtac_port_info[port_index=%d]->subdirs = %p mtac_port_info[port_index=%d]->attr_group=%p",
		port_index,mtac_port_info[port_index]->subdirs,port_index,&mtac_port_info[port_index]->attr_group);
	if (sysfs_create_group(mtac_port_info[port_index]->subdirs, &mtac_port_info[port_index]->attr_group)) {
		log_error("sysfs_create_group failed for LORA in port %d", port);
		return false;
	}

	return true;
}

static bool lora_teardown(enum ap port) {

	int port_index = port - 1;
	struct attribute **attrs = mtac_port_info[port_index]->attr_group.attrs;
	struct attribute *p;
	int i;

	log_info("unloading LORA accessory card in port %d", port);

	if(attrs) {
            // clean up allocated memory for attributes
            for(i=0;attrs[i];i++) {
		p = attrs[i];
		if (p->name) {
                    log_debug("Free name %s",p->name);
                    kfree(p->name);
		}
		log_debug("Free attribute %p",p);
		kfree(p);
            }
            log_debug("kfree %p",attrs);
            kfree(attrs);
	}
	// clean up our "apX/" kobject if it exists
	log_debug("free up directories");
	if (mtac_port_info[port_index]->subdirs) {
            log_debug("Free subdirs %p",mtac_port_info[port_index]->subdirs);
            kobject_put(mtac_port_info[port_index]->subdirs);
	}

	mtac_clear_port_pins(port_index);

	return true;
}

void set_lora_info(struct ap_info* info) {
	snprintf(info->product_id, 32, "%s", PRODUCT_ID_MTAC_LORA);
	info->setup = &lora_setup;
	info->teardown = &lora_teardown;
	info->gpio_pin_name_by_attr_name = &lora_gpio_pin_name_by_attr_name;
}

void set_lora_info_003(struct ap_info* info) {
	snprintf(info->product_id, 32, "%s", PRODUCT_ID_MTAC_LORA_003);
	info->setup = &lora_setup;
	info->teardown = &lora_teardown;
	info->gpio_pin_name_by_attr_name = &lora_gpio_pin_name_by_attr_name;
}

/*
 * Loop through all the slots, and set up the
 * mtac-lora driver for all slots.
 */
static int __init mtac_lora_init(void)
{
	int slot_count = 0;
	int slot_count_lora = 0;
	int slot_count_003 = 0;
	log_debug("mtac_find for LORA called");
	slot_count_lora = mtac_find(set_lora_info,PRODUCT_ID_MTAC_LORA);
	log_debug("mtac_find for MTAC-003 called");
	slot_count_003 = mtac_find(set_lora_info_003,PRODUCT_ID_MTAC_LORA_003);
	slot_count = slot_count_lora + slot_count_003;
	if (slot_count < 1) {
		log_debug("No MTAC LORA found");
		if (slot_count < 0)
			return slot_count;
		else
			return -ENXIO;
	}
	return 0;
}

/* We can only tear down our own device */
static void __exit mtac_lora_exit(void)
{
	mtac_free(PRODUCT_ID_MTAC_LORA,lora_setup,"lora");
	mtac_free(PRODUCT_ID_MTAC_LORA_003,lora_setup,"lora");
	log_info("exiting");
}

module_init(mtac_lora_init);
module_exit(mtac_lora_exit);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_VERSION(DRIVER_VERSION);
MODULE_LICENSE("GPL");