forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
468 lines
12 KiB
468 lines
12 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* Nano River Technologies viperboard i2c master driver |
|
* |
|
* (C) 2012 by Lemonage GmbH |
|
* Author: Lars Poeschel <[email protected]> |
|
* All rights reserved. |
|
*/ |
|
|
|
#include <linux/kernel.h> |
|
#include <linux/errno.h> |
|
#include <linux/module.h> |
|
#include <linux/slab.h> |
|
#include <linux/types.h> |
|
#include <linux/mutex.h> |
|
#include <linux/platform_device.h> |
|
|
|
#include <linux/usb.h> |
|
#include <linux/i2c.h> |
|
|
|
#include <linux/mfd/viperboard.h> |
|
|
|
struct vprbrd_i2c { |
|
struct i2c_adapter i2c; |
|
u8 bus_freq_param; |
|
}; |
|
|
|
/* i2c bus frequency module parameter */ |
|
static u8 i2c_bus_param; |
|
static unsigned int i2c_bus_freq = 100; |
|
module_param(i2c_bus_freq, int, 0); |
|
MODULE_PARM_DESC(i2c_bus_freq, |
|
"i2c bus frequency in khz (default is 100) valid values: 10, 100, 200, 400, 1000, 3000, 6000"); |
|
|
|
static int vprbrd_i2c_status(struct i2c_adapter *i2c, |
|
struct vprbrd_i2c_status *status, bool prev_error) |
|
{ |
|
u16 bytes_xfer; |
|
int ret; |
|
struct vprbrd *vb = (struct vprbrd *)i2c->algo_data; |
|
|
|
/* check for protocol error */ |
|
bytes_xfer = sizeof(struct vprbrd_i2c_status); |
|
|
|
ret = usb_control_msg(vb->usb_dev, usb_rcvctrlpipe(vb->usb_dev, 0), |
|
VPRBRD_USB_REQUEST_I2C, VPRBRD_USB_TYPE_IN, 0x0000, 0x0000, |
|
status, bytes_xfer, VPRBRD_USB_TIMEOUT_MS); |
|
|
|
if (ret != bytes_xfer) |
|
prev_error = true; |
|
|
|
if (prev_error) { |
|
dev_err(&i2c->dev, "failure in usb communication\n"); |
|
return -EREMOTEIO; |
|
} |
|
|
|
dev_dbg(&i2c->dev, " status = %d\n", status->status); |
|
if (status->status != 0x00) { |
|
dev_err(&i2c->dev, "failure: i2c protocol error\n"); |
|
return -EPROTO; |
|
} |
|
return 0; |
|
} |
|
|
|
static int vprbrd_i2c_receive(struct usb_device *usb_dev, |
|
struct vprbrd_i2c_read_msg *rmsg, int bytes_xfer) |
|
{ |
|
int ret, bytes_actual; |
|
int error = 0; |
|
|
|
/* send the read request */ |
|
ret = usb_bulk_msg(usb_dev, |
|
usb_sndbulkpipe(usb_dev, VPRBRD_EP_OUT), rmsg, |
|
sizeof(struct vprbrd_i2c_read_hdr), &bytes_actual, |
|
VPRBRD_USB_TIMEOUT_MS); |
|
|
|
if ((ret < 0) |
|
|| (bytes_actual != sizeof(struct vprbrd_i2c_read_hdr))) { |
|
dev_err(&usb_dev->dev, "failure transmitting usb\n"); |
|
error = -EREMOTEIO; |
|
} |
|
|
|
/* read the actual data */ |
|
ret = usb_bulk_msg(usb_dev, |
|
usb_rcvbulkpipe(usb_dev, VPRBRD_EP_IN), rmsg, |
|
bytes_xfer, &bytes_actual, VPRBRD_USB_TIMEOUT_MS); |
|
|
|
if ((ret < 0) || (bytes_xfer != bytes_actual)) { |
|
dev_err(&usb_dev->dev, "failure receiving usb\n"); |
|
error = -EREMOTEIO; |
|
} |
|
return error; |
|
} |
|
|
|
static int vprbrd_i2c_addr(struct usb_device *usb_dev, |
|
struct vprbrd_i2c_addr_msg *amsg) |
|
{ |
|
int ret, bytes_actual; |
|
|
|
ret = usb_bulk_msg(usb_dev, |
|
usb_sndbulkpipe(usb_dev, VPRBRD_EP_OUT), amsg, |
|
sizeof(struct vprbrd_i2c_addr_msg), &bytes_actual, |
|
VPRBRD_USB_TIMEOUT_MS); |
|
|
|
if ((ret < 0) || |
|
(sizeof(struct vprbrd_i2c_addr_msg) != bytes_actual)) { |
|
dev_err(&usb_dev->dev, "failure transmitting usb\n"); |
|
return -EREMOTEIO; |
|
} |
|
return 0; |
|
} |
|
|
|
static int vprbrd_i2c_read(struct vprbrd *vb, struct i2c_msg *msg) |
|
{ |
|
int ret; |
|
u16 remain_len, len1, len2, start = 0x0000; |
|
struct vprbrd_i2c_read_msg *rmsg = |
|
(struct vprbrd_i2c_read_msg *)vb->buf; |
|
|
|
remain_len = msg->len; |
|
rmsg->header.cmd = VPRBRD_I2C_CMD_READ; |
|
while (remain_len > 0) { |
|
rmsg->header.addr = cpu_to_le16(start + 0x4000); |
|
if (remain_len <= 255) { |
|
len1 = remain_len; |
|
len2 = 0x00; |
|
rmsg->header.len0 = remain_len; |
|
rmsg->header.len1 = 0x00; |
|
rmsg->header.len2 = 0x00; |
|
rmsg->header.len3 = 0x00; |
|
rmsg->header.len4 = 0x00; |
|
rmsg->header.len5 = 0x00; |
|
remain_len = 0; |
|
} else if (remain_len <= 510) { |
|
len1 = remain_len; |
|
len2 = 0x00; |
|
rmsg->header.len0 = remain_len - 255; |
|
rmsg->header.len1 = 0xff; |
|
rmsg->header.len2 = 0x00; |
|
rmsg->header.len3 = 0x00; |
|
rmsg->header.len4 = 0x00; |
|
rmsg->header.len5 = 0x00; |
|
remain_len = 0; |
|
} else if (remain_len <= 512) { |
|
len1 = remain_len; |
|
len2 = 0x00; |
|
rmsg->header.len0 = remain_len - 510; |
|
rmsg->header.len1 = 0xff; |
|
rmsg->header.len2 = 0xff; |
|
rmsg->header.len3 = 0x00; |
|
rmsg->header.len4 = 0x00; |
|
rmsg->header.len5 = 0x00; |
|
remain_len = 0; |
|
} else if (remain_len <= 767) { |
|
len1 = 512; |
|
len2 = remain_len - 512; |
|
rmsg->header.len0 = 0x02; |
|
rmsg->header.len1 = 0xff; |
|
rmsg->header.len2 = 0xff; |
|
rmsg->header.len3 = remain_len - 512; |
|
rmsg->header.len4 = 0x00; |
|
rmsg->header.len5 = 0x00; |
|
remain_len = 0; |
|
} else if (remain_len <= 1022) { |
|
len1 = 512; |
|
len2 = remain_len - 512; |
|
rmsg->header.len0 = 0x02; |
|
rmsg->header.len1 = 0xff; |
|
rmsg->header.len2 = 0xff; |
|
rmsg->header.len3 = remain_len - 767; |
|
rmsg->header.len4 = 0xff; |
|
rmsg->header.len5 = 0x00; |
|
remain_len = 0; |
|
} else if (remain_len <= 1024) { |
|
len1 = 512; |
|
len2 = remain_len - 512; |
|
rmsg->header.len0 = 0x02; |
|
rmsg->header.len1 = 0xff; |
|
rmsg->header.len2 = 0xff; |
|
rmsg->header.len3 = remain_len - 1022; |
|
rmsg->header.len4 = 0xff; |
|
rmsg->header.len5 = 0xff; |
|
remain_len = 0; |
|
} else { |
|
len1 = 512; |
|
len2 = 512; |
|
rmsg->header.len0 = 0x02; |
|
rmsg->header.len1 = 0xff; |
|
rmsg->header.len2 = 0xff; |
|
rmsg->header.len3 = 0x02; |
|
rmsg->header.len4 = 0xff; |
|
rmsg->header.len5 = 0xff; |
|
remain_len -= 1024; |
|
start += 1024; |
|
} |
|
rmsg->header.tf1 = cpu_to_le16(len1); |
|
rmsg->header.tf2 = cpu_to_le16(len2); |
|
|
|
/* first read transfer */ |
|
ret = vprbrd_i2c_receive(vb->usb_dev, rmsg, len1); |
|
if (ret < 0) |
|
return ret; |
|
/* copy the received data */ |
|
memcpy(msg->buf + start, rmsg, len1); |
|
|
|
/* second read transfer if neccessary */ |
|
if (len2 > 0) { |
|
ret = vprbrd_i2c_receive(vb->usb_dev, rmsg, len2); |
|
if (ret < 0) |
|
return ret; |
|
/* copy the received data */ |
|
memcpy(msg->buf + start + 512, rmsg, len2); |
|
} |
|
} |
|
return 0; |
|
} |
|
|
|
static int vprbrd_i2c_write(struct vprbrd *vb, struct i2c_msg *msg) |
|
{ |
|
int ret, bytes_actual; |
|
u16 remain_len, bytes_xfer, |
|
start = 0x0000; |
|
struct vprbrd_i2c_write_msg *wmsg = |
|
(struct vprbrd_i2c_write_msg *)vb->buf; |
|
|
|
remain_len = msg->len; |
|
wmsg->header.cmd = VPRBRD_I2C_CMD_WRITE; |
|
wmsg->header.last = 0x00; |
|
wmsg->header.chan = 0x00; |
|
wmsg->header.spi = 0x0000; |
|
while (remain_len > 0) { |
|
wmsg->header.addr = cpu_to_le16(start + 0x4000); |
|
if (remain_len > 503) { |
|
wmsg->header.len1 = 0xff; |
|
wmsg->header.len2 = 0xf8; |
|
remain_len -= 503; |
|
bytes_xfer = 503 + sizeof(struct vprbrd_i2c_write_hdr); |
|
start += 503; |
|
} else if (remain_len > 255) { |
|
wmsg->header.len1 = 0xff; |
|
wmsg->header.len2 = (remain_len - 255); |
|
bytes_xfer = remain_len + |
|
sizeof(struct vprbrd_i2c_write_hdr); |
|
remain_len = 0; |
|
} else { |
|
wmsg->header.len1 = remain_len; |
|
wmsg->header.len2 = 0x00; |
|
bytes_xfer = remain_len + |
|
sizeof(struct vprbrd_i2c_write_hdr); |
|
remain_len = 0; |
|
} |
|
memcpy(wmsg->data, msg->buf + start, |
|
bytes_xfer - sizeof(struct vprbrd_i2c_write_hdr)); |
|
|
|
ret = usb_bulk_msg(vb->usb_dev, |
|
usb_sndbulkpipe(vb->usb_dev, |
|
VPRBRD_EP_OUT), wmsg, |
|
bytes_xfer, &bytes_actual, VPRBRD_USB_TIMEOUT_MS); |
|
if ((ret < 0) || (bytes_xfer != bytes_actual)) |
|
return -EREMOTEIO; |
|
} |
|
return 0; |
|
} |
|
|
|
static int vprbrd_i2c_xfer(struct i2c_adapter *i2c, struct i2c_msg *msgs, |
|
int num) |
|
{ |
|
struct i2c_msg *pmsg; |
|
int i, ret, |
|
error = 0; |
|
struct vprbrd *vb = (struct vprbrd *)i2c->algo_data; |
|
struct vprbrd_i2c_addr_msg *amsg = |
|
(struct vprbrd_i2c_addr_msg *)vb->buf; |
|
struct vprbrd_i2c_status *smsg = (struct vprbrd_i2c_status *)vb->buf; |
|
|
|
dev_dbg(&i2c->dev, "master xfer %d messages:\n", num); |
|
|
|
for (i = 0 ; i < num ; i++) { |
|
pmsg = &msgs[i]; |
|
|
|
dev_dbg(&i2c->dev, |
|
" %d: %s (flags %d) %d bytes to 0x%02x\n", |
|
i, pmsg->flags & I2C_M_RD ? "read" : "write", |
|
pmsg->flags, pmsg->len, pmsg->addr); |
|
|
|
mutex_lock(&vb->lock); |
|
/* directly send the message */ |
|
if (pmsg->flags & I2C_M_RD) { |
|
/* read data */ |
|
amsg->cmd = VPRBRD_I2C_CMD_ADDR; |
|
amsg->unknown2 = 0x00; |
|
amsg->unknown3 = 0x00; |
|
amsg->addr = pmsg->addr; |
|
amsg->unknown1 = 0x01; |
|
amsg->len = cpu_to_le16(pmsg->len); |
|
/* send the addr and len, we're interested to board */ |
|
ret = vprbrd_i2c_addr(vb->usb_dev, amsg); |
|
if (ret < 0) |
|
error = ret; |
|
|
|
ret = vprbrd_i2c_read(vb, pmsg); |
|
if (ret < 0) |
|
error = ret; |
|
|
|
ret = vprbrd_i2c_status(i2c, smsg, error); |
|
if (ret < 0) |
|
error = ret; |
|
/* in case of protocol error, return the error */ |
|
if (error < 0) |
|
goto error; |
|
} else { |
|
/* write data */ |
|
ret = vprbrd_i2c_write(vb, pmsg); |
|
|
|
amsg->cmd = VPRBRD_I2C_CMD_ADDR; |
|
amsg->unknown2 = 0x00; |
|
amsg->unknown3 = 0x00; |
|
amsg->addr = pmsg->addr; |
|
amsg->unknown1 = 0x00; |
|
amsg->len = cpu_to_le16(pmsg->len); |
|
/* send the addr, the data goes to to board */ |
|
ret = vprbrd_i2c_addr(vb->usb_dev, amsg); |
|
if (ret < 0) |
|
error = ret; |
|
|
|
ret = vprbrd_i2c_status(i2c, smsg, error); |
|
if (ret < 0) |
|
error = ret; |
|
|
|
if (error < 0) |
|
goto error; |
|
} |
|
mutex_unlock(&vb->lock); |
|
} |
|
return num; |
|
error: |
|
mutex_unlock(&vb->lock); |
|
return error; |
|
} |
|
|
|
static u32 vprbrd_i2c_func(struct i2c_adapter *i2c) |
|
{ |
|
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; |
|
} |
|
|
|
/* This is the actual algorithm we define */ |
|
static const struct i2c_algorithm vprbrd_algorithm = { |
|
.master_xfer = vprbrd_i2c_xfer, |
|
.functionality = vprbrd_i2c_func, |
|
}; |
|
|
|
static const struct i2c_adapter_quirks vprbrd_quirks = { |
|
.max_read_len = 2048, |
|
.max_write_len = 2048, |
|
}; |
|
|
|
static int vprbrd_i2c_probe(struct platform_device *pdev) |
|
{ |
|
struct vprbrd *vb = dev_get_drvdata(pdev->dev.parent); |
|
struct vprbrd_i2c *vb_i2c; |
|
int ret; |
|
int pipe; |
|
|
|
vb_i2c = devm_kzalloc(&pdev->dev, sizeof(*vb_i2c), GFP_KERNEL); |
|
if (vb_i2c == NULL) |
|
return -ENOMEM; |
|
|
|
/* setup i2c adapter description */ |
|
vb_i2c->i2c.owner = THIS_MODULE; |
|
vb_i2c->i2c.class = I2C_CLASS_HWMON; |
|
vb_i2c->i2c.algo = &vprbrd_algorithm; |
|
vb_i2c->i2c.quirks = &vprbrd_quirks; |
|
vb_i2c->i2c.algo_data = vb; |
|
/* save the param in usb capabable memory */ |
|
vb_i2c->bus_freq_param = i2c_bus_param; |
|
|
|
snprintf(vb_i2c->i2c.name, sizeof(vb_i2c->i2c.name), |
|
"viperboard at bus %03d device %03d", |
|
vb->usb_dev->bus->busnum, vb->usb_dev->devnum); |
|
|
|
/* setting the bus frequency */ |
|
if ((i2c_bus_param <= VPRBRD_I2C_FREQ_10KHZ) |
|
&& (i2c_bus_param >= VPRBRD_I2C_FREQ_6MHZ)) { |
|
pipe = usb_sndctrlpipe(vb->usb_dev, 0); |
|
ret = usb_control_msg(vb->usb_dev, pipe, |
|
VPRBRD_USB_REQUEST_I2C_FREQ, VPRBRD_USB_TYPE_OUT, |
|
0x0000, 0x0000, &vb_i2c->bus_freq_param, 1, |
|
VPRBRD_USB_TIMEOUT_MS); |
|
if (ret != 1) { |
|
dev_err(&pdev->dev, "failure setting i2c_bus_freq to %d\n", |
|
i2c_bus_freq); |
|
return -EIO; |
|
} |
|
} else { |
|
dev_err(&pdev->dev, |
|
"invalid i2c_bus_freq setting:%d\n", i2c_bus_freq); |
|
return -EIO; |
|
} |
|
|
|
vb_i2c->i2c.dev.parent = &pdev->dev; |
|
|
|
/* attach to i2c layer */ |
|
i2c_add_adapter(&vb_i2c->i2c); |
|
|
|
platform_set_drvdata(pdev, vb_i2c); |
|
|
|
return 0; |
|
} |
|
|
|
static int vprbrd_i2c_remove(struct platform_device *pdev) |
|
{ |
|
struct vprbrd_i2c *vb_i2c = platform_get_drvdata(pdev); |
|
|
|
i2c_del_adapter(&vb_i2c->i2c); |
|
|
|
return 0; |
|
} |
|
|
|
static struct platform_driver vprbrd_i2c_driver = { |
|
.driver.name = "viperboard-i2c", |
|
.driver.owner = THIS_MODULE, |
|
.probe = vprbrd_i2c_probe, |
|
.remove = vprbrd_i2c_remove, |
|
}; |
|
|
|
static int __init vprbrd_i2c_init(void) |
|
{ |
|
switch (i2c_bus_freq) { |
|
case 6000: |
|
i2c_bus_param = VPRBRD_I2C_FREQ_6MHZ; |
|
break; |
|
case 3000: |
|
i2c_bus_param = VPRBRD_I2C_FREQ_3MHZ; |
|
break; |
|
case 1000: |
|
i2c_bus_param = VPRBRD_I2C_FREQ_1MHZ; |
|
break; |
|
case 400: |
|
i2c_bus_param = VPRBRD_I2C_FREQ_400KHZ; |
|
break; |
|
case 200: |
|
i2c_bus_param = VPRBRD_I2C_FREQ_200KHZ; |
|
break; |
|
case 100: |
|
i2c_bus_param = VPRBRD_I2C_FREQ_100KHZ; |
|
break; |
|
case 10: |
|
i2c_bus_param = VPRBRD_I2C_FREQ_10KHZ; |
|
break; |
|
default: |
|
pr_warn("invalid i2c_bus_freq (%d)\n", i2c_bus_freq); |
|
i2c_bus_param = VPRBRD_I2C_FREQ_100KHZ; |
|
} |
|
|
|
return platform_driver_register(&vprbrd_i2c_driver); |
|
} |
|
subsys_initcall(vprbrd_i2c_init); |
|
|
|
static void __exit vprbrd_i2c_exit(void) |
|
{ |
|
platform_driver_unregister(&vprbrd_i2c_driver); |
|
} |
|
module_exit(vprbrd_i2c_exit); |
|
|
|
MODULE_AUTHOR("Lars Poeschel <[email protected]>"); |
|
MODULE_DESCRIPTION("I2C master driver for Nano River Techs Viperboard"); |
|
MODULE_LICENSE("GPL"); |
|
MODULE_ALIAS("platform:viperboard-i2c");
|
|
|