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Release 4.14 drivers/mfd/cros_ec_i2c.c

Directory: drivers/mfd
/*
 * ChromeOS EC multi-function device (I2C)
 *
 * Copyright (C) 2012 Google, Inc
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/mfd/cros_ec.h>
#include <linux/mfd/cros_ec_commands.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

/**
 * Request format for protocol v3
 * byte 0       0xda (EC_COMMAND_PROTOCOL_3)
 * byte 1-8     struct ec_host_request
 * byte 10-     response data
 */

struct ec_host_request_i2c {
	/* Always 0xda to backward compatible with v2 struct */
	
uint8_t  command_protocol;
	
struct ec_host_request ec_request;

} __packed;


/*
 * Response format for protocol v3
 * byte 0       result code
 * byte 1       packet_length
 * byte 2-9     struct ec_host_response
 * byte 10-     response data
 */

struct ec_host_response_i2c {
	
uint8_t result;
	
uint8_t packet_length;
	
struct ec_host_response ec_response;

} __packed;


static inline struct cros_ec_device *to_ec_dev(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); return i2c_get_clientdata(client); }

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Stephen Barber1963.33%150.00%
Simon Glass1136.67%150.00%
Total30100.00%2100.00%


static int cros_ec_pkt_xfer_i2c(struct cros_ec_device *ec_dev, struct cros_ec_command *msg) { struct i2c_client *client = ec_dev->priv; int ret = -ENOMEM; int i; int packet_len; u8 *out_buf = NULL; u8 *in_buf = NULL; u8 sum; struct i2c_msg i2c_msg[2]; struct ec_host_response *ec_response; struct ec_host_request_i2c *ec_request_i2c; struct ec_host_response_i2c *ec_response_i2c; int request_header_size = sizeof(struct ec_host_request_i2c); int response_header_size = sizeof(struct ec_host_response_i2c); i2c_msg[0].addr = client->addr; i2c_msg[0].flags = 0; i2c_msg[1].addr = client->addr; i2c_msg[1].flags = I2C_M_RD; packet_len = msg->insize + response_header_size; BUG_ON(packet_len > ec_dev->din_size); in_buf = ec_dev->din; i2c_msg[1].len = packet_len; i2c_msg[1].buf = (char *) in_buf; packet_len = msg->outsize + request_header_size; BUG_ON(packet_len > ec_dev->dout_size); out_buf = ec_dev->dout; i2c_msg[0].len = packet_len; i2c_msg[0].buf = (char *) out_buf; /* create request data */ ec_request_i2c = (struct ec_host_request_i2c *) out_buf; ec_request_i2c->command_protocol = EC_COMMAND_PROTOCOL_3; ec_dev->dout++; ret = cros_ec_prepare_tx(ec_dev, msg); ec_dev->dout--; /* send command to EC and read answer */ ret = i2c_transfer(client->adapter, i2c_msg, 2); if (ret < 0) { dev_dbg(ec_dev->dev, "i2c transfer failed: %d\n", ret); goto done; } else if (ret != 2) { dev_err(ec_dev->dev, "failed to get response: %d\n", ret); ret = -EIO; goto done; } ec_response_i2c = (struct ec_host_response_i2c *) in_buf; msg->result = ec_response_i2c->result; ec_response = &ec_response_i2c->ec_response; switch (msg->result) { case EC_RES_SUCCESS: break; case EC_RES_IN_PROGRESS: ret = -EAGAIN; dev_dbg(ec_dev->dev, "command 0x%02x in progress\n", msg->command); goto done; default: dev_dbg(ec_dev->dev, "command 0x%02x returned %d\n", msg->command, msg->result); /* * When we send v3 request to v2 ec, ec won't recognize the * 0xda (EC_COMMAND_PROTOCOL_3) and will return with status * EC_RES_INVALID_COMMAND with zero data length. * * In case of invalid command for v3 protocol the data length * will be at least sizeof(struct ec_host_response) */ if (ec_response_i2c->result == EC_RES_INVALID_COMMAND && ec_response_i2c->packet_length == 0) { ret = -EPROTONOSUPPORT; goto done; } } if (ec_response_i2c->packet_length < sizeof(struct ec_host_response)) { dev_err(ec_dev->dev, "response of %u bytes too short; not a full header\n", ec_response_i2c->packet_length); ret = -EBADMSG; goto done; } if (msg->insize < ec_response->data_len) { dev_err(ec_dev->dev, "response data size is too large: expected %u, got %u\n", msg->insize, ec_response->data_len); ret = -EMSGSIZE; goto done; } /* copy response packet payload and compute checksum */ sum = 0; for (i = 0; i < sizeof(struct ec_host_response); i++) sum += ((u8 *)ec_response)[i]; memcpy(msg->data, in_buf + response_header_size, ec_response->data_len); for (i = 0; i < ec_response->data_len; i++) sum += msg->data[i]; /* All bytes should sum to zero */ if (sum) { dev_err(ec_dev->dev, "bad packet checksum\n"); ret = -EBADMSG; goto done; } ret = ec_response->data_len; done: if (msg->command == EC_CMD_REBOOT_EC) msleep(EC_REBOOT_DELAY_MS); return ret; }

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Stephen Barber61098.71%150.00%
Simon Glass81.29%150.00%
Total618100.00%2100.00%


static int cros_ec_cmd_xfer_i2c(struct cros_ec_device *ec_dev, struct cros_ec_command *msg) { struct i2c_client *client = ec_dev->priv; int ret = -ENOMEM; int i; int len; int packet_len; u8 *out_buf = NULL; u8 *in_buf = NULL; u8 sum; struct i2c_msg i2c_msg[2]; i2c_msg[0].addr = client->addr; i2c_msg[0].flags = 0; i2c_msg[1].addr = client->addr; i2c_msg[1].flags = I2C_M_RD; /* * allocate larger packet (one byte for checksum, one byte for * length, and one for result code) */ packet_len = msg->insize + 3; in_buf = kzalloc(packet_len, GFP_KERNEL); if (!in_buf) goto done; i2c_msg[1].len = packet_len; i2c_msg[1].buf = (char *)in_buf; /* * allocate larger packet (one byte for checksum, one for * command code, one for length, and one for command version) */ packet_len = msg->outsize + 4; out_buf = kzalloc(packet_len, GFP_KERNEL); if (!out_buf) goto done; i2c_msg[0].len = packet_len; i2c_msg[0].buf = (char *)out_buf; out_buf[0] = EC_CMD_VERSION0 + msg->version; out_buf[1] = msg->command; out_buf[2] = msg->outsize; /* copy message payload and compute checksum */ sum = out_buf[0] + out_buf[1] + out_buf[2]; for (i = 0; i < msg->outsize; i++) { out_buf[3 + i] = msg->data[i]; sum += out_buf[3 + i]; } out_buf[3 + msg->outsize] = sum; /* send command to EC and read answer */ ret = i2c_transfer(client->adapter, i2c_msg, 2); if (ret < 0) { dev_err(ec_dev->dev, "i2c transfer failed: %d\n", ret); goto done; } else if (ret != 2) { dev_err(ec_dev->dev, "failed to get response: %d\n", ret); ret = -EIO; goto done; } /* check response error code */ msg->result = i2c_msg[1].buf[0]; ret = cros_ec_check_result(ec_dev, msg); if (ret) goto done; len = in_buf[1]; if (len > msg->insize) { dev_err(ec_dev->dev, "packet too long (%d bytes, expected %d)", len, msg->insize); ret = -ENOSPC; goto done; } /* copy response packet payload and compute checksum */ sum = in_buf[0] + in_buf[1]; for (i = 0; i < len; i++) { msg->data[i] = in_buf[2 + i]; sum += in_buf[2 + i]; } dev_dbg(ec_dev->dev, "packet: %*ph, sum = %02x\n", i2c_msg[1].len, in_buf, sum); if (sum != in_buf[2 + len]) { dev_err(ec_dev->dev, "bad packet checksum\n"); ret = -EBADMSG; goto done; } ret = len; done: kfree(in_buf); kfree(out_buf); if (msg->command == EC_CMD_REBOOT_EC) msleep(EC_REBOOT_DELAY_MS); return ret; }

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Simon Glass48485.82%114.29%
Douglas Anderson468.16%114.29%
Bill Richardson193.37%342.86%
Stephen Barber132.30%114.29%
Javier Martinez Canillas20.35%114.29%
Total564100.00%7100.00%


static int cros_ec_i2c_probe(struct i2c_client *client, const struct i2c_device_id *dev_id) { struct device *dev = &client->dev; struct cros_ec_device *ec_dev = NULL; int err; ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL); if (!ec_dev) return -ENOMEM; i2c_set_clientdata(client, ec_dev); ec_dev->dev = dev; ec_dev->priv = client; ec_dev->irq = client->irq; ec_dev->cmd_xfer = cros_ec_cmd_xfer_i2c; ec_dev->pkt_xfer = cros_ec_pkt_xfer_i2c; ec_dev->phys_name = client->adapter->name; ec_dev->din_size = sizeof(struct ec_host_response_i2c) + sizeof(struct ec_response_get_protocol_info); ec_dev->dout_size = sizeof(struct ec_host_request_i2c); err = cros_ec_register(ec_dev); if (err) { dev_err(dev, "cannot register EC\n"); return err; } return 0; }

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Simon Glass12778.40%120.00%
Stephen Barber3219.75%240.00%
Bill Richardson21.23%120.00%
Thierry Reding10.62%120.00%
Total162100.00%5100.00%


static int cros_ec_i2c_remove(struct i2c_client *client) { struct cros_ec_device *ec_dev = i2c_get_clientdata(client); cros_ec_remove(ec_dev); return 0; }

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Simon Glass2896.55%150.00%
Thierry Reding13.45%150.00%
Total29100.00%2100.00%

#ifdef CONFIG_PM_SLEEP
static int cros_ec_i2c_suspend(struct device *dev) { struct cros_ec_device *ec_dev = to_ec_dev(dev); return cros_ec_suspend(ec_dev); }

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Simon Glass27100.00%1100.00%
Total27100.00%1100.00%


static int cros_ec_i2c_resume(struct device *dev) { struct cros_ec_device *ec_dev = to_ec_dev(dev); return cros_ec_resume(ec_dev); }

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Simon Glass27100.00%1100.00%
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#endif static SIMPLE_DEV_PM_OPS(cros_ec_i2c_pm_ops, cros_ec_i2c_suspend, cros_ec_i2c_resume); static const struct of_device_id cros_ec_i2c_of_match[] = { { .compatible = "google,cros-ec-i2c", }, { /* sentinel */ }, }; MODULE_DEVICE_TABLE(of, cros_ec_i2c_of_match); static const struct i2c_device_id cros_ec_i2c_id[] = { { "cros-ec-i2c", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, cros_ec_i2c_id); static struct i2c_driver cros_ec_driver = { .driver = { .name = "cros-ec-i2c", .of_match_table = of_match_ptr(cros_ec_i2c_of_match), .pm = &cros_ec_i2c_pm_ops, }, .probe = cros_ec_i2c_probe, .remove = cros_ec_i2c_remove, .id_table = cros_ec_i2c_id, }; module_i2c_driver(cros_ec_driver); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("ChromeOS EC multi function device");

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Simon Glass82750.30%110.00%
Stephen Barber70943.13%220.00%
Douglas Anderson462.80%110.00%
Javier Martinez Canillas372.25%220.00%
Bill Richardson211.28%330.00%
Thierry Reding40.24%110.00%
Total1644100.00%10100.00%
Directory: drivers/mfd
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