364 lines
		
	
	
		
			8.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			364 lines
		
	
	
		
			8.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| /*
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|  * Power supply driver for ChromeOS EC based Peripheral Device Charger.
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|  *
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|  * Copyright 2020 Google LLC.
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|  */
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| 
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| #include <linux/module.h>
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| #include <linux/notifier.h>
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| #include <linux/platform_data/cros_ec_commands.h>
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| #include <linux/platform_data/cros_ec_proto.h>
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| #include <linux/platform_device.h>
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| #include <linux/power_supply.h>
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| #include <linux/slab.h>
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| #include <linux/stringify.h>
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| #include <linux/types.h>
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| #include <asm/unaligned.h>
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| 
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| #define DRV_NAME		"cros-ec-pchg"
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| #define PCHG_DIR_PREFIX		"peripheral"
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| #define PCHG_DIR_NAME		PCHG_DIR_PREFIX "%d"
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| #define PCHG_DIR_NAME_LENGTH \
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| 		sizeof(PCHG_DIR_PREFIX __stringify(EC_PCHG_MAX_PORTS))
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| #define PCHG_CACHE_UPDATE_DELAY	msecs_to_jiffies(500)
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| 
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| struct port_data {
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| 	int port_number;
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| 	char name[PCHG_DIR_NAME_LENGTH];
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| 	struct power_supply *psy;
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| 	struct power_supply_desc psy_desc;
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| 	int psy_status;
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| 	int battery_percentage;
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| 	int charge_type;
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| 	struct charger_data *charger;
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| 	unsigned long last_update;
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| };
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| 
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| struct charger_data {
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| 	struct device *dev;
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| 	struct cros_ec_dev *ec_dev;
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| 	struct cros_ec_device *ec_device;
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| 	int num_registered_psy;
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| 	struct port_data *ports[EC_PCHG_MAX_PORTS];
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| 	struct notifier_block notifier;
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| };
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| 
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| static enum power_supply_property cros_pchg_props[] = {
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| 	POWER_SUPPLY_PROP_STATUS,
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| 	POWER_SUPPLY_PROP_CHARGE_TYPE,
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| 	POWER_SUPPLY_PROP_CAPACITY,
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| 	POWER_SUPPLY_PROP_SCOPE,
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| };
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| 
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| static int cros_pchg_ec_command(const struct charger_data *charger,
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| 				unsigned int version,
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| 				unsigned int command,
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| 				const void *outdata,
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| 				unsigned int outsize,
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| 				void *indata,
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| 				unsigned int insize)
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| {
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| 	struct cros_ec_dev *ec_dev = charger->ec_dev;
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| 	struct cros_ec_command *msg;
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| 	int ret;
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| 
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| 	msg = kzalloc(struct_size(msg, data, max(outsize, insize)), GFP_KERNEL);
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| 	if (!msg)
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| 		return -ENOMEM;
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| 
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| 	msg->version = version;
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| 	msg->command = ec_dev->cmd_offset + command;
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| 	msg->outsize = outsize;
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| 	msg->insize = insize;
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| 
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| 	if (outsize)
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| 		memcpy(msg->data, outdata, outsize);
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| 
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| 	ret = cros_ec_cmd_xfer_status(charger->ec_device, msg);
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| 	if (ret >= 0 && insize)
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| 		memcpy(indata, msg->data, insize);
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| 
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| 	kfree(msg);
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| 	return ret;
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| }
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| 
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| static const unsigned int pchg_cmd_version = 1;
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| 
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| static bool cros_pchg_cmd_ver_check(const struct charger_data *charger)
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| {
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| 	struct ec_params_get_cmd_versions_v1 req;
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| 	struct ec_response_get_cmd_versions rsp;
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| 	int ret;
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| 
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| 	req.cmd = EC_CMD_PCHG;
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| 	ret = cros_pchg_ec_command(charger, 1, EC_CMD_GET_CMD_VERSIONS,
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| 				   &req, sizeof(req), &rsp, sizeof(rsp));
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| 	if (ret < 0) {
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| 		dev_warn(charger->dev,
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| 			 "Unable to get versions of EC_CMD_PCHG (err:%d)\n",
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| 			 ret);
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| 		return false;
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| 	}
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| 
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| 	return !!(rsp.version_mask & BIT(pchg_cmd_version));
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| }
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| 
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| static int cros_pchg_port_count(const struct charger_data *charger)
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| {
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| 	struct ec_response_pchg_count rsp;
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| 	int ret;
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| 
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| 	ret = cros_pchg_ec_command(charger, 0, EC_CMD_PCHG_COUNT,
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| 				   NULL, 0, &rsp, sizeof(rsp));
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| 	if (ret < 0) {
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| 		dev_warn(charger->dev,
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| 			 "Unable to get number or ports (err:%d)\n", ret);
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| 		return ret;
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| 	}
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| 
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| 	return rsp.port_count;
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| }
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| 
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| static int cros_pchg_get_status(struct port_data *port)
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| {
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| 	struct charger_data *charger = port->charger;
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| 	struct ec_params_pchg req;
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| 	struct ec_response_pchg rsp;
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| 	struct device *dev = charger->dev;
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| 	int old_status = port->psy_status;
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| 	int old_percentage = port->battery_percentage;
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| 	int ret;
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| 
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| 	req.port = port->port_number;
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| 	ret = cros_pchg_ec_command(charger, pchg_cmd_version, EC_CMD_PCHG,
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| 				   &req, sizeof(req), &rsp, sizeof(rsp));
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| 	if (ret < 0) {
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| 		dev_err(dev, "Unable to get port.%d status (err:%d)\n",
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| 			port->port_number, ret);
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| 		return ret;
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| 	}
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| 
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| 	switch (rsp.state) {
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| 	case PCHG_STATE_RESET:
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| 	case PCHG_STATE_INITIALIZED:
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| 	case PCHG_STATE_ENABLED:
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| 	default:
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| 		port->psy_status = POWER_SUPPLY_STATUS_UNKNOWN;
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| 		port->charge_type = POWER_SUPPLY_CHARGE_TYPE_NONE;
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| 		break;
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| 	case PCHG_STATE_DETECTED:
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| 		port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
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| 		port->charge_type = POWER_SUPPLY_CHARGE_TYPE_TRICKLE;
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| 		break;
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| 	case PCHG_STATE_CHARGING:
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| 		port->psy_status = POWER_SUPPLY_STATUS_CHARGING;
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| 		port->charge_type = POWER_SUPPLY_CHARGE_TYPE_STANDARD;
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| 		break;
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| 	case PCHG_STATE_FULL:
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| 		port->psy_status = POWER_SUPPLY_STATUS_FULL;
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| 		port->charge_type = POWER_SUPPLY_CHARGE_TYPE_NONE;
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| 		break;
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| 	}
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| 
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| 	port->battery_percentage = rsp.battery_percentage;
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| 
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| 	if (port->psy_status != old_status ||
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| 			port->battery_percentage != old_percentage)
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| 		power_supply_changed(port->psy);
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| 
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| 	dev_dbg(dev,
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| 		"Port %d: state=%d battery=%d%%\n",
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| 		port->port_number, rsp.state, rsp.battery_percentage);
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| 
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| 	return 0;
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| }
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| 
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| static int cros_pchg_get_port_status(struct port_data *port, bool ratelimit)
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| {
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| 	int ret;
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| 
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| 	if (ratelimit &&
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| 	    time_is_after_jiffies(port->last_update + PCHG_CACHE_UPDATE_DELAY))
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| 		return 0;
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| 
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| 	ret = cros_pchg_get_status(port);
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| 	if (ret < 0)
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| 		return ret;
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| 
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| 	port->last_update = jiffies;
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| 
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| 	return ret;
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| }
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| 
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| static int cros_pchg_get_prop(struct power_supply *psy,
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| 			      enum power_supply_property psp,
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| 			      union power_supply_propval *val)
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| {
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| 	struct port_data *port = power_supply_get_drvdata(psy);
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| 
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| 	switch (psp) {
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| 	case POWER_SUPPLY_PROP_STATUS:
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| 	case POWER_SUPPLY_PROP_CAPACITY:
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| 	case POWER_SUPPLY_PROP_CHARGE_TYPE:
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| 		cros_pchg_get_port_status(port, true);
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| 		break;
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| 	default:
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| 		break;
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| 	}
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| 
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| 	switch (psp) {
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| 	case POWER_SUPPLY_PROP_STATUS:
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| 		val->intval = port->psy_status;
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| 		break;
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| 	case POWER_SUPPLY_PROP_CAPACITY:
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| 		val->intval = port->battery_percentage;
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| 		break;
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| 	case POWER_SUPPLY_PROP_CHARGE_TYPE:
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| 		val->intval = port->charge_type;
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| 		break;
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| 	case POWER_SUPPLY_PROP_SCOPE:
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| 		val->intval = POWER_SUPPLY_SCOPE_DEVICE;
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| 		break;
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| 	default:
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| 		return -EINVAL;
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| 	}
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| 
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| 	return 0;
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| }
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| 
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| static int cros_pchg_event(const struct charger_data *charger,
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| 			   unsigned long host_event)
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| {
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| 	int i;
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| 
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| 	for (i = 0; i < charger->num_registered_psy; i++)
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| 		cros_pchg_get_port_status(charger->ports[i], false);
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| 
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| 	return NOTIFY_OK;
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| }
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| 
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| static int cros_ec_notify(struct notifier_block *nb,
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| 			  unsigned long queued_during_suspend,
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| 			  void *data)
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| {
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| 	struct cros_ec_device *ec_dev = data;
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| 	struct charger_data *charger =
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| 			container_of(nb, struct charger_data, notifier);
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| 	u32 host_event;
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| 
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| 	if (ec_dev->event_data.event_type != EC_MKBP_EVENT_PCHG ||
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| 			ec_dev->event_size != sizeof(host_event))
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| 		return NOTIFY_DONE;
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| 
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| 	host_event = get_unaligned_le32(&ec_dev->event_data.data.host_event);
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| 
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| 	if (!(host_event & EC_MKBP_PCHG_DEVICE_EVENT))
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| 		return NOTIFY_DONE;
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| 
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| 	return cros_pchg_event(charger, host_event);
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| }
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| 
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| static int cros_pchg_probe(struct platform_device *pdev)
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| {
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| 	struct device *dev = &pdev->dev;
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| 	struct cros_ec_dev *ec_dev = dev_get_drvdata(dev->parent);
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| 	struct cros_ec_device *ec_device = ec_dev->ec_dev;
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| 	struct power_supply_desc *psy_desc;
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| 	struct charger_data *charger;
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| 	struct power_supply *psy;
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| 	struct port_data *port;
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| 	struct notifier_block *nb;
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| 	int num_ports;
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| 	int ret;
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| 	int i;
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| 
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| 	charger = devm_kzalloc(dev, sizeof(*charger), GFP_KERNEL);
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| 	if (!charger)
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| 		return -ENOMEM;
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| 
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| 	charger->dev = dev;
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| 	charger->ec_dev = ec_dev;
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| 	charger->ec_device = ec_device;
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| 
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| 	ret = cros_pchg_port_count(charger);
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| 	if (ret <= 0) {
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| 		/*
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| 		 * This feature is enabled by the EC and the kernel driver is
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| 		 * included by default for CrOS devices. Don't need to be loud
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| 		 * since this error can be normal.
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| 		 */
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| 		dev_info(dev, "No peripheral charge ports (err:%d)\n", ret);
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| 		return -ENODEV;
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| 	}
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| 
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| 	if (!cros_pchg_cmd_ver_check(charger)) {
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| 		dev_err(dev, "EC_CMD_PCHG version %d isn't available.\n",
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| 			pchg_cmd_version);
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| 		return -EOPNOTSUPP;
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| 	}
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| 
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| 	num_ports = ret;
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| 	if (num_ports > EC_PCHG_MAX_PORTS) {
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| 		dev_err(dev, "Too many peripheral charge ports (%d)\n",
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| 			num_ports);
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| 		return -ENOBUFS;
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| 	}
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| 
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| 	dev_info(dev, "%d peripheral charge ports found\n", num_ports);
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| 
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| 	for (i = 0; i < num_ports; i++) {
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| 		struct power_supply_config psy_cfg = {};
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| 
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| 		port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
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| 		if (!port)
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| 			return -ENOMEM;
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| 
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| 		port->charger = charger;
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| 		port->port_number = i;
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| 		snprintf(port->name, sizeof(port->name), PCHG_DIR_NAME, i);
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| 
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| 		psy_desc = &port->psy_desc;
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| 		psy_desc->name = port->name;
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| 		psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
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| 		psy_desc->get_property = cros_pchg_get_prop;
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| 		psy_desc->external_power_changed = NULL;
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| 		psy_desc->properties = cros_pchg_props;
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| 		psy_desc->num_properties = ARRAY_SIZE(cros_pchg_props);
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| 		psy_cfg.drv_data = port;
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| 
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| 		psy = devm_power_supply_register(dev, psy_desc, &psy_cfg);
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| 		if (IS_ERR(psy))
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| 			return dev_err_probe(dev, PTR_ERR(psy),
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| 					"Failed to register power supply\n");
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| 		port->psy = psy;
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| 
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| 		charger->ports[charger->num_registered_psy++] = port;
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| 	}
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| 
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| 	if (!charger->num_registered_psy)
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| 		return -ENODEV;
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| 
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| 	nb = &charger->notifier;
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| 	nb->notifier_call = cros_ec_notify;
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| 	ret = blocking_notifier_chain_register(&ec_dev->ec_dev->event_notifier,
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| 					       nb);
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| 	if (ret < 0)
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| 		dev_err(dev, "Failed to register notifier (err:%d)\n", ret);
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| 
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| 	return 0;
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| }
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| 
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| static struct platform_driver cros_pchg_driver = {
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| 	.driver = {
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| 		.name = DRV_NAME,
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| 	},
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| 	.probe = cros_pchg_probe
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| };
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| 
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| module_platform_driver(cros_pchg_driver);
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| 
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| MODULE_LICENSE("GPL");
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| MODULE_DESCRIPTION("ChromeOS EC peripheral device charger");
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| MODULE_ALIAS("platform:" DRV_NAME);
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