On 04/20/2018 05:31 PM, Russell King - ARM Linux wrote:
> Hi Hans,
>
> Any comments?
I have been traveling and haven't had time to look at this. Next week will
be busy as well, but I expect to be able to look at it the week after that.
I remember from the previous series that I couldn't test it with my BeagleBone
Black board (the calibration gpio had to switch from in to out but it wasn't allowed
since it had an associated irq). That's still a problem?
I didn't see any changes in that area when I did a quick scan.
Regards,
Hans
>
> Thanks.
>
> On Mon, Apr 09, 2018 at 01:16:32PM +0100, Russell King wrote:
>> Add a CEC driver for the TDA9950, which is a stand-alone I2C CEC device,
>> but is also integrated into HDMI transceivers such as the TDA9989 and
>> TDA19989.
>>
>> The TDA9950 contains a command processor which handles retransmissions
>> and the low level bus protocol. The driver just has to read and write
>> the messages, and handle error conditions.
>>
>> Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
>> ---
>> drivers/gpu/drm/i2c/Kconfig | 5 +
>> drivers/gpu/drm/i2c/Makefile | 1 +
>> drivers/gpu/drm/i2c/tda9950.c | 509 ++++++++++++++++++++++++++++++++++
>> include/linux/platform_data/tda9950.h | 16 ++
>> 4 files changed, 531 insertions(+)
>> create mode 100644 drivers/gpu/drm/i2c/tda9950.c
>> create mode 100644 include/linux/platform_data/tda9950.h
>>
>> diff --git a/drivers/gpu/drm/i2c/Kconfig b/drivers/gpu/drm/i2c/Kconfig
>> index a6c92beb410a..3a232f5ff0a1 100644
>> --- a/drivers/gpu/drm/i2c/Kconfig
>> +++ b/drivers/gpu/drm/i2c/Kconfig
>> @@ -26,4 +26,9 @@ config DRM_I2C_NXP_TDA998X
>> help
>> Support for NXP Semiconductors TDA998X HDMI encoders.
>>
>> +config DRM_I2C_NXP_TDA9950
>> + tristate "NXP Semiconductors TDA9950/TDA998X HDMI CEC"
>> + select CEC_NOTIFIER
>> + select CEC_CORE
>> +
>> endmenu
>> diff --git a/drivers/gpu/drm/i2c/Makefile b/drivers/gpu/drm/i2c/Makefile
>> index b20100c18ffb..a962f6f08568 100644
>> --- a/drivers/gpu/drm/i2c/Makefile
>> +++ b/drivers/gpu/drm/i2c/Makefile
>> @@ -7,3 +7,4 @@ obj-$(CONFIG_DRM_I2C_SIL164) += sil164.o
>>
>> tda998x-y := tda998x_drv.o
>> obj-$(CONFIG_DRM_I2C_NXP_TDA998X) += tda998x.o
>> +obj-$(CONFIG_DRM_I2C_NXP_TDA9950) += tda9950.o
>> diff --git a/drivers/gpu/drm/i2c/tda9950.c b/drivers/gpu/drm/i2c/tda9950.c
>> new file mode 100644
>> index 000000000000..3f7396caad48
>> --- /dev/null
>> +++ b/drivers/gpu/drm/i2c/tda9950.c
>> @@ -0,0 +1,509 @@
>> +/*
>> + * TDA9950 Consumer Electronics Control driver
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + *
>> + * The NXP TDA9950 implements the HDMI Consumer Electronics Control
>> + * interface. The host interface is similar to a mailbox: the data
>> + * registers starting at REG_CDR0 are written to send a command to the
>> + * internal CPU, and replies are read from these registers.
>> + *
>> + * As the data registers represent a mailbox, they must be accessed
>> + * as a single I2C transaction. See the TDA9950 data sheet for details.
>> + */
>> +#include <linux/delay.h>
>> +#include <linux/i2c.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/module.h>
>> +#include <linux/platform_data/tda9950.h>
>> +#include <linux/slab.h>
>> +#include <drm/drm_edid.h>
>> +#include <media/cec.h>
>> +#include <media/cec-notifier.h>
>> +
>> +enum {
>> + REG_CSR = 0x00,
>> + CSR_BUSY = BIT(7),
>> + CSR_INT = BIT(6),
>> + CSR_ERR = BIT(5),
>> +
>> + REG_CER = 0x01,
>> +
>> + REG_CVR = 0x02,
>> +
>> + REG_CCR = 0x03,
>> + CCR_RESET = BIT(7),
>> + CCR_ON = BIT(6),
>> +
>> + REG_ACKH = 0x04,
>> + REG_ACKL = 0x05,
>> +
>> + REG_CCONR = 0x06,
>> + CCONR_ENABLE_ERROR = BIT(4),
>> + CCONR_RETRY_MASK = 7,
>> +
>> + REG_CDR0 = 0x07,
>> +
>> + CDR1_REQ = 0x00,
>> + CDR1_CNF = 0x01,
>> + CDR1_IND = 0x81,
>> + CDR1_ERR = 0x82,
>> + CDR1_IER = 0x83,
>> +
>> + CDR2_CNF_SUCCESS = 0x00,
>> + CDR2_CNF_OFF_STATE = 0x80,
>> + CDR2_CNF_BAD_REQ = 0x81,
>> + CDR2_CNF_CEC_ACCESS = 0x82,
>> + CDR2_CNF_ARB_ERROR = 0x83,
>> + CDR2_CNF_BAD_TIMING = 0x84,
>> + CDR2_CNF_NACK_ADDR = 0x85,
>> + CDR2_CNF_NACK_DATA = 0x86,
>> +};
>> +
>> +struct tda9950_priv {
>> + struct i2c_client *client;
>> + struct device *hdmi;
>> + struct cec_adapter *adap;
>> + struct tda9950_glue *glue;
>> + u16 addresses;
>> + struct cec_msg rx_msg;
>> + struct cec_notifier *notify;
>> + bool open;
>> +};
>> +
>> +static int tda9950_write_range(struct i2c_client *client, u8 addr, u8 *p, int cnt)
>> +{
>> + struct i2c_msg msg;
>> + u8 buf[cnt + 1];
>> + int ret;
>> +
>> + buf[0] = addr;
>> + memcpy(buf + 1, p, cnt);
>> +
>> + msg.addr = client->addr;
>> + msg.flags = 0;
>> + msg.len = cnt + 1;
>> + msg.buf = buf;
>> +
>> + dev_dbg(&client->dev, "wr 0x%02x: %*ph\n", addr, cnt, p);
>> +
>> + ret = i2c_transfer(client->adapter, &msg, 1);
>> + if (ret < 0)
>> + dev_err(&client->dev, "Error %d writing to cec:0x%x\n", ret, addr);
>> + return ret < 0 ? ret : 0;
>> +}
>> +
>> +static void tda9950_write(struct i2c_client *client, u8 addr, u8 val)
>> +{
>> + tda9950_write_range(client, addr, &val, 1);
>> +}
>> +
>> +static int tda9950_read_range(struct i2c_client *client, u8 addr, u8 *p, int cnt)
>> +{
>> + struct i2c_msg msg[2];
>> + int ret;
>> +
>> + msg[0].addr = client->addr;
>> + msg[0].flags = 0;
>> + msg[0].len = 1;
>> + msg[0].buf = &addr;
>> + msg[1].addr = client->addr;
>> + msg[1].flags = I2C_M_RD;
>> + msg[1].len = cnt;
>> + msg[1].buf = p;
>> +
>> + ret = i2c_transfer(client->adapter, msg, 2);
>> + if (ret < 0)
>> + dev_err(&client->dev, "Error %d reading from cec:0x%x\n", ret, addr);
>> +
>> + dev_dbg(&client->dev, "rd 0x%02x: %*ph\n", addr, cnt, p);
>> +
>> + return ret;
>> +}
>> +
>> +static u8 tda9950_read(struct i2c_client *client, u8 addr)
>> +{
>> + int ret;
>> + u8 val;
>> +
>> + ret = tda9950_read_range(client, addr, &val, 1);
>> + if (ret < 0)
>> + val = 0;
>> +
>> + return val;
>> +}
>> +
>> +static irqreturn_t tda9950_irq(int irq, void *data)
>> +{
>> + struct tda9950_priv *priv = data;
>> + unsigned int tx_status;
>> + u8 csr, cconr, buf[19];
>> + u8 arb_lost_cnt, nack_cnt, err_cnt;
>> +
>> + if (!priv->open)
>> + return IRQ_NONE;
>> +
>> + csr = tda9950_read(priv->client, REG_CSR);
>> + if (!(csr & CSR_INT))
>> + return IRQ_NONE;
>> +
>> + cconr = tda9950_read(priv->client, REG_CCONR) & CCONR_RETRY_MASK;
>> +
>> + tda9950_read_range(priv->client, REG_CDR0, buf, sizeof(buf));
>> +
>> + /*
>> + * This should never happen: the data sheet says that there will
>> + * always be a valid message if the interrupt line is asserted.
>> + */
>> + if (buf[0] == 0) {
>> + dev_warn(&priv->client->dev, "interrupt pending, but no message?\n");
>> + return IRQ_NONE;
>> + }
>> +
>> + switch (buf[1]) {
>> + case CDR1_CNF: /* transmit result */
>> + arb_lost_cnt = nack_cnt = err_cnt = 0;
>> + switch (buf[2]) {
>> + case CDR2_CNF_SUCCESS:
>> + tx_status = CEC_TX_STATUS_OK;
>> + break;
>> +
>> + case CDR2_CNF_ARB_ERROR:
>> + tx_status = CEC_TX_STATUS_ARB_LOST;
>> + arb_lost_cnt = cconr;
>> + break;
>> +
>> + case CDR2_CNF_NACK_ADDR:
>> + tx_status = CEC_TX_STATUS_NACK;
>> + nack_cnt = cconr;
>> + break;
>> +
>> + default: /* some other error, refer to TDA9950 docs */
>> + dev_err(&priv->client->dev, "CNF reply error 0x%02x\n",
>> + buf[2]);
>> + tx_status = CEC_TX_STATUS_ERROR;
>> + err_cnt = cconr;
>> + break;
>> + }
>> + /* TDA9950 executes all retries for us */
>> + tx_status |= CEC_TX_STATUS_MAX_RETRIES;
>> + cec_transmit_done(priv->adap, tx_status, arb_lost_cnt,
>> + nack_cnt, 0, err_cnt);
>> + break;
>> +
>> + case CDR1_IND:
>> + priv->rx_msg.len = buf[0] - 2;
>> + if (priv->rx_msg.len > CEC_MAX_MSG_SIZE)
>> + priv->rx_msg.len = CEC_MAX_MSG_SIZE;
>> +
>> + memcpy(priv->rx_msg.msg, buf + 2, priv->rx_msg.len);
>> + cec_received_msg(priv->adap, &priv->rx_msg);
>> + break;
>> +
>> + default: /* unknown */
>> + dev_err(&priv->client->dev, "unknown service id 0x%02x\n",
>> + buf[1]);
>> + break;
>> + }
>> +
>> + return IRQ_HANDLED;
>> +}
>> +
>> +static int tda9950_cec_transmit(struct cec_adapter *adap, u8 attempts,
>> + u32 signal_free_time, struct cec_msg *msg)
>> +{
>> + struct tda9950_priv *priv = adap->priv;
>> + u8 buf[CEC_MAX_MSG_SIZE + 2];
>> +
>> + buf[0] = 2 + msg->len;
>> + buf[1] = CDR1_REQ;
>> + memcpy(buf + 2, msg->msg, msg->len);
>> +
>> + if (attempts > 5)
>> + attempts = 5;
>> +
>> + tda9950_write(priv->client, REG_CCONR, attempts);
>> +
>> + return tda9950_write_range(priv->client, REG_CDR0, buf, 2 + msg->len);
>> +}
>> +
>> +static int tda9950_cec_adap_log_addr(struct cec_adapter *adap, u8 addr)
>> +{
>> + struct tda9950_priv *priv = adap->priv;
>> + u16 addresses;
>> + u8 buf[2];
>> +
>> + if (addr == CEC_LOG_ADDR_INVALID)
>> + addresses = priv->addresses = 0;
>> + else
>> + addresses = priv->addresses |= BIT(addr);
>> +
>> + /* TDA9950 doesn't want address 15 set */
>> + addresses &= 0x7fff;
>> + buf[0] = addresses >> 8;
>> + buf[1] = addresses;
>> +
>> + return tda9950_write_range(priv->client, REG_ACKH, buf, 2);
>> +}
>> +
>> +/*
>> + * When operating as part of the TDA998x, we need additional handling
>> + * to initialise and shut down the TDA9950 part of the device. These
>> + * two hooks are provided to allow the TDA998x code to perform those
>> + * activities.
>> + */
>> +static int tda9950_glue_open(struct tda9950_priv *priv)
>> +{
>> + int ret = 0;
>> +
>> + if (priv->glue && priv->glue->open)
>> + ret = priv->glue->open(priv->glue->data);
>> +
>> + priv->open = true;
>> +
>> + return ret;
>> +}
>> +
>> +static void tda9950_glue_release(struct tda9950_priv *priv)
>> +{
>> + priv->open = false;
>> +
>> + if (priv->glue && priv->glue->release)
>> + priv->glue->release(priv->glue->data);
>> +}
>> +
>> +static int tda9950_open(struct tda9950_priv *priv)
>> +{
>> + struct i2c_client *client = priv->client;
>> + int ret;
>> +
>> + ret = tda9950_glue_open(priv);
>> + if (ret)
>> + return ret;
>> +
>> + /* Reset the TDA9950, and wait 250ms for it to recover */
>> + tda9950_write(client, REG_CCR, CCR_RESET);
>> + msleep(250);
>> +
>> + tda9950_cec_adap_log_addr(priv->adap, CEC_LOG_ADDR_INVALID);
>> +
>> + /* Start the command processor */
>> + tda9950_write(client, REG_CCR, CCR_ON);
>> +
>> + return 0;
>> +}
>> +
>> +static void tda9950_release(struct tda9950_priv *priv)
>> +{
>> + struct i2c_client *client = priv->client;
>> + int timeout = 50;
>> + u8 csr;
>> +
>> + /* Stop the command processor */
>> + tda9950_write(client, REG_CCR, 0);
>> +
>> + /* Wait up to .5s for it to signal non-busy */
>> + do {
>> + csr = tda9950_read(client, REG_CSR);
>> + if (!(csr & CSR_BUSY) || --timeout)
>> + break;
>> + msleep(10);
>> + } while (1);
>> +
>> + /* Warn the user that their IRQ may die if it's shared. */
>> + if (csr & CSR_BUSY)
>> + dev_warn(&client->dev, "command processor failed to stop, irq%d may die (csr=0x%02x)\n",
>> + client->irq, csr);
>> +
>> + tda9950_glue_release(priv);
>> +}
>> +
>> +static int tda9950_cec_adap_enable(struct cec_adapter *adap, bool enable)
>> +{
>> + struct tda9950_priv *priv = adap->priv;
>> +
>> + if (!enable) {
>> + tda9950_release(priv);
>> + return 0;
>> + } else {
>> + return tda9950_open(priv);
>> + }
>> +}
>> +
>> +static const struct cec_adap_ops tda9950_cec_ops = {
>> + .adap_enable = tda9950_cec_adap_enable,
>> + .adap_log_addr = tda9950_cec_adap_log_addr,
>> + .adap_transmit = tda9950_cec_transmit,
>> +};
>> +
>> +/*
>> + * When operating as part of the TDA998x, we need to claim additional
>> + * resources. These two hooks permit the management of those resources.
>> + */
>> +static void tda9950_devm_glue_exit(void *data)
>> +{
>> + struct tda9950_glue *glue = data;
>> +
>> + if (glue && glue->exit)
>> + glue->exit(glue->data);
>> +}
>> +
>> +static int tda9950_devm_glue_init(struct device *dev, struct tda9950_glue *glue)
>> +{
>> + int ret;
>> +
>> + if (glue && glue->init) {
>> + ret = glue->init(glue->data);
>> + if (ret)
>> + return ret;
>> + }
>> +
>> + ret = devm_add_action(dev, tda9950_devm_glue_exit, glue);
>> + if (ret)
>> + tda9950_devm_glue_exit(glue);
>> +
>> + return ret;
>> +}
>> +
>> +static void tda9950_cec_del(void *data)
>> +{
>> + struct tda9950_priv *priv = data;
>> +
>> + cec_delete_adapter(priv->adap);
>> +}
>> +
>> +static int tda9950_probe(struct i2c_client *client,
>> + const struct i2c_device_id *id)
>> +{
>> + struct tda9950_glue *glue = client->dev.platform_data;
>> + struct device *dev = &client->dev;
>> + struct tda9950_priv *priv;
>> + unsigned long irqflags;
>> + int ret;
>> + u8 cvr;
>> +
>> + /*
>> + * We must have I2C functionality: our multi-byte accesses
>> + * must be performed as a single contiguous transaction.
>> + */
>> + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
>> + dev_err(&client->dev,
>> + "adapter does not support I2C functionality\n");
>> + return -ENXIO;
>> + }
>> +
>> + /* We must have an interrupt to be functional. */
>> + if (client->irq <= 0) {
>> + dev_err(&client->dev, "driver requires an interrupt\n");
>> + return -ENXIO;
>> + }
>> +
>> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>> + if (!priv)
>> + return -ENOMEM;
>> +
>> + priv->client = client;
>> + priv->glue = glue;
>> +
>> + i2c_set_clientdata(client, priv);
>> +
>> + /*
>> + * If we're part of a TDA998x, we want the class devices to be
>> + * associated with the HDMI Tx so we have a tight relationship
>> + * between the HDMI interface and the CEC interface.
>> + */
>> + priv->hdmi = dev;
>> + if (glue && glue->parent)
>> + priv->hdmi = glue->parent;
>> +
>> + priv->adap = cec_allocate_adapter(&tda9950_cec_ops, priv, "tda9950",
>> + CEC_CAP_DEFAULTS,
>> + CEC_MAX_LOG_ADDRS);
>> + if (IS_ERR(priv->adap))
>> + return PTR_ERR(priv->adap);
>> +
>> + ret = devm_add_action(dev, tda9950_cec_del, priv);
>> + if (ret) {
>> + cec_delete_adapter(priv->adap);
>> + return ret;
>> + }
>> +
>> + ret = tda9950_devm_glue_init(dev, glue);
>> + if (ret)
>> + return ret;
>> +
>> + ret = tda9950_glue_open(priv);
>> + if (ret)
>> + return ret;
>> +
>> + cvr = tda9950_read(client, REG_CVR);
>> +
>> + dev_info(&client->dev,
>> + "TDA9950 CEC interface, hardware version %u.%u\n",
>> + cvr >> 4, cvr & 15);
>> +
>> + tda9950_glue_release(priv);
>> +
>> + irqflags = IRQF_TRIGGER_FALLING;
>> + if (glue)
>> + irqflags = glue->irq_flags;
>> +
>> + ret = devm_request_threaded_irq(dev, client->irq, NULL, tda9950_irq,
>> + irqflags | IRQF_SHARED | IRQF_ONESHOT,
>> + dev_name(&client->dev), priv);
>> + if (ret < 0)
>> + return ret;
>> +
>> + priv->notify = cec_notifier_get(priv->hdmi);
>> + if (!priv->notify)
>> + return -ENOMEM;
>> +
>> + ret = cec_register_adapter(priv->adap, priv->hdmi);
>> + if (ret < 0) {
>> + cec_notifier_put(priv->notify);
>> + return ret;
>> + }
>> +
>> + /*
>> + * CEC documentation says we must not call cec_delete_adapter
>> + * after a successful call to cec_register_adapter().
>> + */
>> + devm_remove_action(dev, tda9950_cec_del, priv);
>> +
>> + cec_register_cec_notifier(priv->adap, priv->notify);
>> +
>> + return 0;
>> +}
>> +
>> +static int tda9950_remove(struct i2c_client *client)
>> +{
>> + struct tda9950_priv *priv = i2c_get_clientdata(client);
>> +
>> + cec_unregister_adapter(priv->adap);
>> + cec_notifier_put(priv->notify);
>> +
>> + return 0;
>> +}
>> +
>> +static struct i2c_device_id tda9950_ids[] = {
>> + { "tda9950", 0 },
>> + { },
>> +};
>> +MODULE_DEVICE_TABLE(i2c, tda9950_ids);
>> +
>> +static struct i2c_driver tda9950_driver = {
>> + .probe = tda9950_probe,
>> + .remove = tda9950_remove,
>> + .driver = {
>> + .name = "tda9950",
>> + },
>> + .id_table = tda9950_ids,
>> +};
>> +
>> +module_i2c_driver(tda9950_driver);
>> +
>> +MODULE_AUTHOR("Russell King <rmk+kernel@xxxxxxxxxxxxxxx>");
>> +MODULE_DESCRIPTION("TDA9950/TDA998x Consumer Electronics Control Driver");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/include/linux/platform_data/tda9950.h b/include/linux/platform_data/tda9950.h
>> new file mode 100644
>> index 000000000000..c65efd461102
>> --- /dev/null
>> +++ b/include/linux/platform_data/tda9950.h
>> @@ -0,0 +1,16 @@
>> +#ifndef LINUX_PLATFORM_DATA_TDA9950_H
>> +#define LINUX_PLATFORM_DATA_TDA9950_H
>> +
>> +struct device;
>> +
>> +struct tda9950_glue {
>> + struct device *parent;
>> + unsigned long irq_flags;
>> + void *data;
>> + int (*init)(void *);
>> + void (*exit)(void *);
>> + int (*open)(void *);
>> + void (*release)(void *);
>> +};
>> +
>> +#endif
>> --
>> 2.7.4
>>
>
