blob: b8755337b3941538e2022c087abfd514b022b019 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Driver for the Chrontel CH7322 CEC Controller
*
* Copyright 2020 Google LLC.
*/
/*
* Notes
*
* - This device powers on in Auto Mode which has limited functionality. This
* driver disables Auto Mode when it attaches.
*
*/
#include <linux/cec.h>
#include <linux/dmi.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/pci.h>
#include <linux/regmap.h>
#include <media/cec.h>
#include <media/cec-notifier.h>
#define CH7322_WRITE 0x00
#define CH7322_WRITE_MSENT 0x80
#define CH7322_WRITE_BOK 0x40
#define CH7322_WRITE_NMASK 0x0f
/* Write buffer is 0x01-0x10 */
#define CH7322_WRBUF 0x01
#define CH7322_WRBUF_LEN 0x10
#define CH7322_READ 0x40
#define CH7322_READ_NRDT 0x80
#define CH7322_READ_MSENT 0x20
#define CH7322_READ_NMASK 0x0f
/* Read buffer is 0x41-0x50 */
#define CH7322_RDBUF 0x41
#define CH7322_RDBUF_LEN 0x10
#define CH7322_MODE 0x11
#define CH7322_MODE_AUTO 0x78
#define CH7322_MODE_SW 0xb5
#define CH7322_RESET 0x12
#define CH7322_RESET_RST 0x00
#define CH7322_POWER 0x13
#define CH7322_POWER_FPD 0x04
#define CH7322_CFG0 0x17
#define CH7322_CFG0_EOBEN 0x40
#define CH7322_CFG0_PEOB 0x20
#define CH7322_CFG0_CLRSPP 0x10
#define CH7322_CFG0_FLOW 0x08
#define CH7322_CFG1 0x1a
#define CH7322_CFG1_STDBYO 0x04
#define CH7322_CFG1_HPBP 0x02
#define CH7322_CFG1_PIO 0x01
#define CH7322_INTCTL 0x1b
#define CH7322_INTCTL_INTPB 0x80
#define CH7322_INTCTL_STDBY 0x40
#define CH7322_INTCTL_HPDFALL 0x20
#define CH7322_INTCTL_HPDRISE 0x10
#define CH7322_INTCTL_RXMSG 0x08
#define CH7322_INTCTL_TXMSG 0x04
#define CH7322_INTCTL_NEWPHA 0x02
#define CH7322_INTCTL_ERROR 0x01
#define CH7322_DVCLKFNH 0x1d
#define CH7322_DVCLKFNL 0x1e
#define CH7322_CTL 0x31
#define CH7322_CTL_FSTDBY 0x80
#define CH7322_CTL_PLSEN 0x40
#define CH7322_CTL_PLSPB 0x20
#define CH7322_CTL_SPADL 0x10
#define CH7322_CTL_HINIT 0x08
#define CH7322_CTL_WPHYA 0x04
#define CH7322_CTL_H1T 0x02
#define CH7322_CTL_S1T 0x01
#define CH7322_PAWH 0x32
#define CH7322_PAWL 0x33
#define CH7322_ADDLW 0x34
#define CH7322_ADDLW_MASK 0xf0
#define CH7322_ADDLR 0x3d
#define CH7322_ADDLR_HPD 0x80
#define CH7322_ADDLR_MASK 0x0f
#define CH7322_INTDATA 0x3e
#define CH7322_INTDATA_MODE 0x80
#define CH7322_INTDATA_STDBY 0x40
#define CH7322_INTDATA_HPDFALL 0x20
#define CH7322_INTDATA_HPDRISE 0x10
#define CH7322_INTDATA_RXMSG 0x08
#define CH7322_INTDATA_TXMSG 0x04
#define CH7322_INTDATA_NEWPHA 0x02
#define CH7322_INTDATA_ERROR 0x01
#define CH7322_EVENT 0x3f
#define CH7322_EVENT_TXERR 0x80
#define CH7322_EVENT_HRST 0x40
#define CH7322_EVENT_HFST 0x20
#define CH7322_EVENT_PHACHG 0x10
#define CH7322_EVENT_ACTST 0x08
#define CH7322_EVENT_PHARDY 0x04
#define CH7322_EVENT_BSOK 0x02
#define CH7322_EVENT_ERRADCF 0x01
#define CH7322_DID 0x51
#define CH7322_DID_CH7322 0x5b
#define CH7322_DID_CH7323 0x5f
#define CH7322_REVISIONID 0x52
#define CH7322_PARH 0x53
#define CH7322_PARL 0x54
#define CH7322_IOCFG2 0x75
#define CH7322_IOCFG_CIO 0x80
#define CH7322_IOCFG_IOCFGMASK 0x78
#define CH7322_IOCFG_AUDIO 0x04
#define CH7322_IOCFG_SPAMST 0x02
#define CH7322_IOCFG_SPAMSP 0x01
#define CH7322_CTL3 0x7b
#define CH7322_CTL3_SWENA 0x80
#define CH7322_CTL3_FC_INIT 0x40
#define CH7322_CTL3_SML_FL 0x20
#define CH7322_CTL3_SM_RDST 0x10
#define CH7322_CTL3_SPP_CIAH 0x08
#define CH7322_CTL3_SPP_CIAL 0x04
#define CH7322_CTL3_SPP_ACTH 0x02
#define CH7322_CTL3_SPP_ACTL 0x01
/* BOK status means NACK */
#define CH7322_TX_FLAG_NACK BIT(0)
/* Device will retry automatically */
#define CH7322_TX_FLAG_RETRY BIT(1)
struct ch7322 {
struct i2c_client *i2c;
struct regmap *regmap;
struct cec_adapter *cec;
struct mutex mutex; /* device access mutex */
u8 tx_flags;
};
static const struct regmap_config ch7322_regmap = {
.reg_bits = 8,
.val_bits = 8,
.max_register = 0x7f,
.disable_locking = true,
};
static int ch7322_send_message(struct ch7322 *ch7322, const struct cec_msg *msg)
{
unsigned int val;
unsigned int len = msg->len;
int ret;
int i;
WARN_ON(!mutex_is_locked(&ch7322->mutex));
if (len > CH7322_WRBUF_LEN || len < 1)
return -EINVAL;
ret = regmap_read(ch7322->regmap, CH7322_WRITE, &val);
if (ret)
return ret;
/* Buffer not ready */
if (!(val & CH7322_WRITE_MSENT))
return -EBUSY;
if (cec_msg_opcode(msg) == -1 &&
cec_msg_initiator(msg) == cec_msg_destination(msg)) {
ch7322->tx_flags = CH7322_TX_FLAG_NACK | CH7322_TX_FLAG_RETRY;
} else if (cec_msg_is_broadcast(msg)) {
ch7322->tx_flags = CH7322_TX_FLAG_NACK;
} else {
ch7322->tx_flags = CH7322_TX_FLAG_RETRY;
}
ret = regmap_write(ch7322->regmap, CH7322_WRITE, len - 1);
if (ret)
return ret;
for (i = 0; i < len; i++) {
ret = regmap_write(ch7322->regmap,
CH7322_WRBUF + i, msg->msg[i]);
if (ret)
return ret;
}
return 0;
}
static int ch7322_receive_message(struct ch7322 *ch7322, struct cec_msg *msg)
{
unsigned int val;
int ret = 0;
int i;
WARN_ON(!mutex_is_locked(&ch7322->mutex));
ret = regmap_read(ch7322->regmap, CH7322_READ, &val);
if (ret)
return ret;
/* Message not ready */
if (!(val & CH7322_READ_NRDT))
return -EIO;
msg->len = (val & CH7322_READ_NMASK) + 1;
/* Read entire RDBUF to clear state */
for (i = 0; i < CH7322_RDBUF_LEN; i++) {
ret = regmap_read(ch7322->regmap, CH7322_RDBUF + i, &val);
if (ret)
return ret;
msg->msg[i] = (u8)val;
}
return 0;
}
static void ch7322_tx_done(struct ch7322 *ch7322)
{
int ret;
unsigned int val;
u8 status, flags;
mutex_lock(&ch7322->mutex);
ret = regmap_read(ch7322->regmap, CH7322_WRITE, &val);
flags = ch7322->tx_flags;
mutex_unlock(&ch7322->mutex);
/*
* The device returns a one-bit OK status which usually means ACK but
* actually means NACK when sending a logical address query or a
* broadcast.
*/
if (ret)
status = CEC_TX_STATUS_ERROR;
else if ((val & CH7322_WRITE_BOK) && (flags & CH7322_TX_FLAG_NACK))
status = CEC_TX_STATUS_NACK;
else if (val & CH7322_WRITE_BOK)
status = CEC_TX_STATUS_OK;
else if (flags & CH7322_TX_FLAG_NACK)
status = CEC_TX_STATUS_OK;
else
status = CEC_TX_STATUS_NACK;
if (status == CEC_TX_STATUS_NACK && (flags & CH7322_TX_FLAG_RETRY))
status |= CEC_TX_STATUS_MAX_RETRIES;
cec_transmit_attempt_done(ch7322->cec, status);
}
static void ch7322_rx_done(struct ch7322 *ch7322)
{
struct cec_msg msg;
int ret;
mutex_lock(&ch7322->mutex);
ret = ch7322_receive_message(ch7322, &msg);
mutex_unlock(&ch7322->mutex);
if (ret)
dev_err(&ch7322->i2c->dev, "cec receive error: %d\n", ret);
else
cec_received_msg(ch7322->cec, &msg);
}
/*
* This device can either monitor the DDC lines to obtain the physical address
* or it can allow the host to program it. This driver lets the device obtain
* it.
*/
static void ch7322_phys_addr(struct ch7322 *ch7322)
{
unsigned int pah, pal;
int ret = 0;
mutex_lock(&ch7322->mutex);
ret |= regmap_read(ch7322->regmap, CH7322_PARH, &pah);
ret |= regmap_read(ch7322->regmap, CH7322_PARL, &pal);
mutex_unlock(&ch7322->mutex);
if (ret)
dev_err(&ch7322->i2c->dev, "phys addr error\n");
else
cec_s_phys_addr(ch7322->cec, pal | (pah << 8), false);
}
static irqreturn_t ch7322_irq(int irq, void *dev)
{
struct ch7322 *ch7322 = dev;
unsigned int data = 0;
mutex_lock(&ch7322->mutex);
regmap_read(ch7322->regmap, CH7322_INTDATA, &data);
regmap_write(ch7322->regmap, CH7322_INTDATA, data);
mutex_unlock(&ch7322->mutex);
if (data & CH7322_INTDATA_HPDFALL)
cec_phys_addr_invalidate(ch7322->cec);
if (data & CH7322_INTDATA_TXMSG)
ch7322_tx_done(ch7322);
if (data & CH7322_INTDATA_RXMSG)
ch7322_rx_done(ch7322);
if (data & CH7322_INTDATA_NEWPHA)
ch7322_phys_addr(ch7322);
if (data & CH7322_INTDATA_ERROR)
dev_dbg(&ch7322->i2c->dev, "unknown error\n");
return IRQ_HANDLED;
}
/* This device is always enabled */
static int ch7322_cec_adap_enable(struct cec_adapter *adap, bool enable)
{
return 0;
}
static int ch7322_cec_adap_log_addr(struct cec_adapter *adap, u8 log_addr)
{
struct ch7322 *ch7322 = cec_get_drvdata(adap);
int ret;
mutex_lock(&ch7322->mutex);
ret = regmap_update_bits(ch7322->regmap, CH7322_ADDLW,
CH7322_ADDLW_MASK, log_addr << 4);
mutex_unlock(&ch7322->mutex);
return ret;
}
static int ch7322_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
u32 signal_free_time, struct cec_msg *msg)
{
struct ch7322 *ch7322 = cec_get_drvdata(adap);
int ret;
mutex_lock(&ch7322->mutex);
ret = ch7322_send_message(ch7322, msg);
mutex_unlock(&ch7322->mutex);
return ret;
}
static const struct cec_adap_ops ch7322_cec_adap_ops = {
.adap_enable = ch7322_cec_adap_enable,
.adap_log_addr = ch7322_cec_adap_log_addr,
.adap_transmit = ch7322_cec_adap_transmit,
};
#if IS_ENABLED(CONFIG_PCI) && IS_ENABLED(CONFIG_DMI)
struct ch7322_conn_match {
const char *dev_name;
const char *pci_name;
const char *port_name;
};
static struct ch7322_conn_match google_endeavour[] = {
{ "i2c-PRP0001:00", "0000:00:02.0", "Port B" },
{ "i2c-PRP0001:01", "0000:00:02.0", "Port C" },
{ },
};
static const struct dmi_system_id ch7322_dmi_table[] = {
{
.matches = {
DMI_MATCH(DMI_BOARD_VENDOR, "Google"),
DMI_MATCH(DMI_BOARD_NAME, "Endeavour"),
},
.driver_data = google_endeavour,
},
{ },
};
/* Make a best-effort attempt to locate a matching HDMI port */
static int ch7322_get_port(struct i2c_client *client,
struct device **dev,
const char **port)
{
const struct dmi_system_id *system;
const struct ch7322_conn_match *conn;
*dev = NULL;
*port = NULL;
system = dmi_first_match(ch7322_dmi_table);
if (!system)
return 0;
for (conn = system->driver_data; conn->dev_name; conn++) {
if (!strcmp(dev_name(&client->dev), conn->dev_name)) {
struct device *d;
d = bus_find_device_by_name(&pci_bus_type, NULL,
conn->pci_name);
if (!d)
return -EPROBE_DEFER;
put_device(d);
*dev = d;
*port = conn->port_name;
return 0;
}
}
return 0;
}
#else
static int ch7322_get_port(struct i2c_client *client,
struct device **dev,
const char **port)
{
*dev = NULL;
*port = NULL;
return 0;
}
#endif
static int ch7322_probe(struct i2c_client *client)
{
struct device *hdmi_dev;
const char *port_name;
struct ch7322 *ch7322;
struct cec_notifier *notifier = NULL;
u32 caps = CEC_CAP_DEFAULTS;
int ret;
unsigned int val;
ret = ch7322_get_port(client, &hdmi_dev, &port_name);
if (ret)
return ret;
if (hdmi_dev)
caps |= CEC_CAP_CONNECTOR_INFO;
ch7322 = devm_kzalloc(&client->dev, sizeof(*ch7322), GFP_KERNEL);
if (!ch7322)
return -ENOMEM;
ch7322->regmap = devm_regmap_init_i2c(client, &ch7322_regmap);
if (IS_ERR(ch7322->regmap))
return PTR_ERR(ch7322->regmap);
ret = regmap_read(ch7322->regmap, CH7322_DID, &val);
if (ret)
return ret;
if (val != CH7322_DID_CH7322)
return -EOPNOTSUPP;
mutex_init(&ch7322->mutex);
ch7322->i2c = client;
ch7322->tx_flags = 0;
i2c_set_clientdata(client, ch7322);
/* Disable auto mode */
ret = regmap_write(ch7322->regmap, CH7322_MODE, CH7322_MODE_SW);
if (ret)
goto err_mutex;
/* Enable logical address register */
ret = regmap_update_bits(ch7322->regmap, CH7322_CTL,
CH7322_CTL_SPADL, CH7322_CTL_SPADL);
if (ret)
goto err_mutex;
ch7322->cec = cec_allocate_adapter(&ch7322_cec_adap_ops, ch7322,
dev_name(&client->dev),
caps, 1);
if (IS_ERR(ch7322->cec)) {
ret = PTR_ERR(ch7322->cec);
goto err_mutex;
}
ch7322->cec->adap_controls_phys_addr = true;
if (hdmi_dev) {
notifier = cec_notifier_cec_adap_register(hdmi_dev,
port_name,
ch7322->cec);
if (!notifier) {
ret = -ENOMEM;
goto err_cec;
}
}
/* Configure, mask, and clear interrupt */
ret = regmap_write(ch7322->regmap, CH7322_CFG1, 0);
if (ret)
goto err_notifier;
ret = regmap_write(ch7322->regmap, CH7322_INTCTL, CH7322_INTCTL_INTPB);
if (ret)
goto err_notifier;
ret = regmap_write(ch7322->regmap, CH7322_INTDATA, 0xff);
if (ret)
goto err_notifier;
/* If HPD is up read physical address */
ret = regmap_read(ch7322->regmap, CH7322_ADDLR, &val);
if (ret)
goto err_notifier;
if (val & CH7322_ADDLR_HPD)
ch7322_phys_addr(ch7322);
ret = devm_request_threaded_irq(&client->dev, client->irq, NULL,
ch7322_irq,
IRQF_ONESHOT | IRQF_TRIGGER_RISING,
client->name, ch7322);
if (ret)
goto err_notifier;
/* Unmask interrupt */
mutex_lock(&ch7322->mutex);
ret = regmap_write(ch7322->regmap, CH7322_INTCTL, 0xff);
mutex_unlock(&ch7322->mutex);
if (ret)
goto err_notifier;
ret = cec_register_adapter(ch7322->cec, &client->dev);
if (ret)
goto err_notifier;
dev_info(&client->dev, "device registered\n");
return 0;
err_notifier:
if (notifier)
cec_notifier_cec_adap_unregister(notifier, ch7322->cec);
err_cec:
cec_delete_adapter(ch7322->cec);
err_mutex:
mutex_destroy(&ch7322->mutex);
return ret;
}
static void ch7322_remove(struct i2c_client *client)
{
struct ch7322 *ch7322 = i2c_get_clientdata(client);
/* Mask interrupt */
mutex_lock(&ch7322->mutex);
regmap_write(ch7322->regmap, CH7322_INTCTL, CH7322_INTCTL_INTPB);
mutex_unlock(&ch7322->mutex);
cec_unregister_adapter(ch7322->cec);
mutex_destroy(&ch7322->mutex);
dev_info(&client->dev, "device unregistered\n");
}
static const struct of_device_id ch7322_of_match[] = {
{ .compatible = "chrontel,ch7322", },
{},
};
MODULE_DEVICE_TABLE(of, ch7322_of_match);
static struct i2c_driver ch7322_i2c_driver = {
.driver = {
.name = "ch7322",
.of_match_table = ch7322_of_match,
},
.probe = ch7322_probe,
.remove = ch7322_remove,
};
module_i2c_driver(ch7322_i2c_driver);
MODULE_DESCRIPTION("Chrontel CH7322 CEC Controller Driver");
MODULE_AUTHOR("Jeff Chase <jnchase@google.com>");
MODULE_LICENSE("GPL");