media: cec: move driver for TDA9950 from drm/i2c
authorDmitry Baryshkov <dmitry.baryshkov@linaro.org>
Mon, 13 Jan 2025 09:53:45 +0000 (11:53 +0200)
committerDmitry Baryshkov <dmitry.baryshkov@linaro.org>
Wed, 12 Feb 2025 22:17:42 +0000 (00:17 +0200)
Move the driver for NXP TDA9950 / CEC part of TDA998x together to
drivers/media/i2c, close to other CEC drivers. Specify 'default
DRM_I2C_NXP_TDA998X' in order to simplify migration from old config
files as the Kconfig name has been changed to follow media/cec style.

Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
Link: https://patchwork.freedesktop.org/patch/msgid/20250113-drm-move-tda998x-v3-2-214e0682a5e4@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
drivers/gpu/drm/i2c/Kconfig
drivers/gpu/drm/i2c/Makefile
drivers/gpu/drm/i2c/tda9950.c [deleted file]
drivers/media/cec/i2c/Kconfig
drivers/media/cec/i2c/Makefile
drivers/media/cec/i2c/tda9950.c [new file with mode: 0644]

index d5200f67958e68a8ec73401f1d3b79cbe0aa303d..1aa2a0bf5cc183b4ce92fc4f7eb61fd0065250d1 100644 (file)
@@ -10,9 +10,4 @@ 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
index 31fd35527d99d7eb23851d290175a3ff0c756772..45791fbfae983eecf58565109cf8eecb6431643b 100644 (file)
@@ -1,4 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0
 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
deleted file mode 100644 (file)
index cbff851..0000000
+++ /dev/null
@@ -1,507 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- *  TDA9950 Consumer Electronics Control driver
- *
- * 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[CEC_MAX_MSG_SIZE + 3];
-       int ret;
-
-       if (WARN_ON(cnt > sizeof(buf) - 1))
-               return -EINVAL;
-
-       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 */
-               if (tx_status != CEC_TX_STATUS_OK)
-                       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)
-{
-       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_CAP_CONNECTOR_INFO,
-                                         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_cec_adap_register(priv->hdmi, NULL,
-                                                     priv->adap);
-       if (!priv->notify)
-               return -ENOMEM;
-
-       ret = cec_register_adapter(priv->adap, priv->hdmi);
-       if (ret < 0) {
-               cec_notifier_cec_adap_unregister(priv->notify, priv->adap);
-               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);
-
-       return 0;
-}
-
-static void tda9950_remove(struct i2c_client *client)
-{
-       struct tda9950_priv *priv = i2c_get_clientdata(client);
-
-       cec_notifier_cec_adap_unregister(priv->notify, priv->adap);
-       cec_unregister_adapter(priv->adap);
-}
-
-static struct i2c_device_id tda9950_ids[] = {
-       { "tda9950" },
-       { }
-};
-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@armlinux.org.uk>");
-MODULE_DESCRIPTION("TDA9950/TDA998x Consumer Electronics Control Driver");
-MODULE_LICENSE("GPL v2");
index d912d143fb3129c6b3d0133dbfceffdd48bd543d..b9d21643eef1892ccff508b1864db30e83570212 100644 (file)
@@ -13,3 +13,12 @@ config CEC_CH7322
          generic CEC framework interface.
          CEC bus is present in the HDMI connector and enables communication
          between compatible devices.
+
+config CEC_NXP_TDA9950
+       tristate "NXP Semiconductors TDA9950/TDA998X HDMI CEC"
+       select CEC_NOTIFIER
+       select CEC_CORE
+       default DRM_I2C_NXP_TDA998X
+       help
+         This is a driver for the NXP TDA9950 CEC controller and for the CEC
+         controller block integrated into several NXP TDA998x HDMI encoders.
index d7496dfd0fa49631299ff56c20e946757e50cdb2..95c9eda5258361c4d9196acb527e0c1b4351dbe0 100644 (file)
@@ -3,3 +3,4 @@
 # Makefile for the CEC I2C device drivers.
 #
 obj-$(CONFIG_CEC_CH7322) += ch7322.o
+obj-$(CONFIG_CEC_NXP_TDA9950) += tda9950.o
diff --git a/drivers/media/cec/i2c/tda9950.c b/drivers/media/cec/i2c/tda9950.c
new file mode 100644 (file)
index 0000000..cbff851
--- /dev/null
@@ -0,0 +1,507 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  TDA9950 Consumer Electronics Control driver
+ *
+ * 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[CEC_MAX_MSG_SIZE + 3];
+       int ret;
+
+       if (WARN_ON(cnt > sizeof(buf) - 1))
+               return -EINVAL;
+
+       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 */
+               if (tx_status != CEC_TX_STATUS_OK)
+                       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)
+{
+       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_CAP_CONNECTOR_INFO,
+                                         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_cec_adap_register(priv->hdmi, NULL,
+                                                     priv->adap);
+       if (!priv->notify)
+               return -ENOMEM;
+
+       ret = cec_register_adapter(priv->adap, priv->hdmi);
+       if (ret < 0) {
+               cec_notifier_cec_adap_unregister(priv->notify, priv->adap);
+               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);
+
+       return 0;
+}
+
+static void tda9950_remove(struct i2c_client *client)
+{
+       struct tda9950_priv *priv = i2c_get_clientdata(client);
+
+       cec_notifier_cec_adap_unregister(priv->notify, priv->adap);
+       cec_unregister_adapter(priv->adap);
+}
+
+static struct i2c_device_id tda9950_ids[] = {
+       { "tda9950" },
+       { }
+};
+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@armlinux.org.uk>");
+MODULE_DESCRIPTION("TDA9950/TDA998x Consumer Electronics Control Driver");
+MODULE_LICENSE("GPL v2");