[PATCHv3 2/2] drm: adv7511/33: add HDMI CEC support

[Hans Verkuil <hverkuil@xs4all.nl>]

From: Hans Verkuil <hans.verkuil@cisco.com>

Add support for HDMI CEC to the drm adv7511/adv7533 drivers.

The CEC registers that we need to use are identical for both drivers,
but they appear at different offsets in the register map.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
 drivers/gpu/drm/bridge/adv7511/Kconfig       |   8 +
 drivers/gpu/drm/bridge/adv7511/Makefile      |   1 +
 drivers/gpu/drm/bridge/adv7511/adv7511.h     |  43 +++-
 drivers/gpu/drm/bridge/adv7511/adv7511_cec.c | 337 +++++++++++++++++++++++++++
 drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 116 +++++++--
 drivers/gpu/drm/bridge/adv7511/adv7533.c     |  38 +--
 6 files changed, 485 insertions(+), 58 deletions(-)
 create mode 100644 drivers/gpu/drm/bridge/adv7511/adv7511_cec.c

diff --git a/drivers/gpu/drm/bridge/adv7511/Kconfig b/drivers/gpu/drm/bridge/adv7511/Kconfig
index 2fed567f9943..592b9d2ec034 100644
--- a/drivers/gpu/drm/bridge/adv7511/Kconfig
+++ b/drivers/gpu/drm/bridge/adv7511/Kconfig
@@ -21,3 +21,11 @@ config DRM_I2C_ADV7533
 	default y
 	help
 	  Support for the Analog Devices ADV7533 DSI to HDMI encoder.
+
+config DRM_I2C_ADV7511_CEC
+	bool "ADV7511/33 HDMI CEC driver"
+	depends on DRM_I2C_ADV7511
+	select CEC_CORE
+	default y
+	help
+	  When selected the HDMI transmitter will support the CEC feature.
diff --git a/drivers/gpu/drm/bridge/adv7511/Makefile b/drivers/gpu/drm/bridge/adv7511/Makefile
index 5ba675534f6e..5bb384938a71 100644
--- a/drivers/gpu/drm/bridge/adv7511/Makefile
+++ b/drivers/gpu/drm/bridge/adv7511/Makefile
@@ -1,4 +1,5 @@
 adv7511-y := adv7511_drv.o
 adv7511-$(CONFIG_DRM_I2C_ADV7511_AUDIO) += adv7511_audio.o
+adv7511-$(CONFIG_DRM_I2C_ADV7511_CEC) += adv7511_cec.o
 adv7511-$(CONFIG_DRM_I2C_ADV7533) += adv7533.o
 obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511.o
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h b/drivers/gpu/drm/bridge/adv7511/adv7511.h
index fe18a5d2d84b..543a5eb91624 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511.h
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511.h
@@ -195,6 +195,25 @@
 #define ADV7511_PACKET_GM(x)	    ADV7511_PACKET(5, x)
 #define ADV7511_PACKET_SPARE(x)	    ADV7511_PACKET(6, x)
 
+#define ADV7511_REG_CEC_TX_FRAME_HDR	0x00
+#define ADV7511_REG_CEC_TX_FRAME_DATA0	0x01
+#define ADV7511_REG_CEC_TX_FRAME_LEN	0x10
+#define ADV7511_REG_CEC_TX_ENABLE	0x11
+#define ADV7511_REG_CEC_TX_RETRY	0x12
+#define ADV7511_REG_CEC_TX_LOW_DRV_CNT	0x14
+#define ADV7511_REG_CEC_RX_FRAME_HDR	0x15
+#define ADV7511_REG_CEC_RX_FRAME_DATA0	0x16
+#define ADV7511_REG_CEC_RX_FRAME_LEN	0x25
+#define ADV7511_REG_CEC_RX_ENABLE	0x26
+#define ADV7511_REG_CEC_RX_BUFFERS	0x4a
+#define ADV7511_REG_CEC_LOG_ADDR_MASK	0x4b
+#define ADV7511_REG_CEC_LOG_ADDR_0_1	0x4c
+#define ADV7511_REG_CEC_LOG_ADDR_2	0x4d
+#define ADV7511_REG_CEC_CLK_DIV		0x4e
+#define ADV7511_REG_CEC_SOFT_RESET	0x50
+
+#define ADV7533_REG_CEC_OFFSET		0x70
+
 enum adv7511_input_clock {
 	ADV7511_INPUT_CLOCK_1X,
 	ADV7511_INPUT_CLOCK_2X,
@@ -297,6 +316,8 @@ enum adv7511_type {
 	ADV7533,
 };
 
+#define ADV7511_MAX_ADDRS 3
+
 struct adv7511 {
 	struct i2c_client *i2c_main;
 	struct i2c_client *i2c_edid;
@@ -343,15 +364,27 @@ struct adv7511 {
 
 	enum adv7511_type type;
 	struct platform_device *audio_pdev;
+
+	struct cec_adapter *cec_adap;
+	u8   cec_addr[ADV7511_MAX_ADDRS];
+	u8   cec_valid_addrs;
+	bool cec_enabled_adap;
+	struct clk *cec_clk;
+	u32 cec_clk_freq;
 };
 
+#ifdef CONFIG_DRM_I2C_ADV7511_CEC
+int adv7511_cec_init(struct device *dev, struct adv7511 *adv7511,
+		     unsigned int offset);
+void adv7511_cec_irq_process(struct adv7511 *adv7511, unsigned int irq1);
+#endif
+
 #ifdef CONFIG_DRM_I2C_ADV7533
 void adv7533_dsi_power_on(struct adv7511 *adv);
 void adv7533_dsi_power_off(struct adv7511 *adv);
 void adv7533_mode_set(struct adv7511 *adv, struct drm_display_mode *mode);
 int adv7533_patch_registers(struct adv7511 *adv);
-void adv7533_uninit_cec(struct adv7511 *adv);
-int adv7533_init_cec(struct adv7511 *adv);
+int adv7533_patch_cec_registers(struct adv7511 *adv);
 int adv7533_attach_dsi(struct adv7511 *adv);
 void adv7533_detach_dsi(struct adv7511 *adv);
 int adv7533_parse_dt(struct device_node *np, struct adv7511 *adv);
@@ -374,11 +407,7 @@ static inline int adv7533_patch_registers(struct adv7511 *adv)
 	return -ENODEV;
 }
 
-static inline void adv7533_uninit_cec(struct adv7511 *adv)
-{
-}
-
-static inline int adv7533_init_cec(struct adv7511 *adv)
+static inline int adv7533_patch_cec_registers(struct adv7511 *adv)
 {
 	return -ENODEV;
 }
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_cec.c b/drivers/gpu/drm/bridge/adv7511/adv7511_cec.c
new file mode 100644
index 000000000000..b33d730e4d73
--- /dev/null
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_cec.c
@@ -0,0 +1,337 @@
+/*
+ * adv7511_cec.c - Analog Devices ADV7511/33 cec driver
+ *
+ * Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+
+#include <media/cec.h>
+
+#include "adv7511.h"
+
+#define ADV7511_INT1_CEC_MASK \
+	(ADV7511_INT1_CEC_TX_READY | ADV7511_INT1_CEC_TX_ARBIT_LOST | \
+	 ADV7511_INT1_CEC_TX_RETRY_TIMEOUT | ADV7511_INT1_CEC_RX_READY1)
+
+static void adv_cec_tx_raw_status(struct adv7511 *adv7511, u8 tx_raw_status)
+{
+	unsigned int offset = adv7511->type == ADV7533 ?
+					ADV7533_REG_CEC_OFFSET : 0;
+	unsigned int val;
+
+	if (regmap_read(adv7511->regmap_cec,
+			ADV7511_REG_CEC_TX_ENABLE + offset, &val))
+		return;
+
+	if ((val & 0x01) == 0)
+		return;
+
+	if (tx_raw_status & ADV7511_INT1_CEC_TX_ARBIT_LOST) {
+		cec_transmit_attempt_done(adv7511->cec_adap,
+					  CEC_TX_STATUS_ARB_LOST);
+		return;
+	}
+	if (tx_raw_status & ADV7511_INT1_CEC_TX_RETRY_TIMEOUT) {
+		u8 status;
+		u8 err_cnt = 0;
+		u8 nack_cnt = 0;
+		u8 low_drive_cnt = 0;
+		unsigned int cnt;
+
+		/*
+		 * We set this status bit since this hardware performs
+		 * retransmissions.
+		 */
+		status = CEC_TX_STATUS_MAX_RETRIES;
+		if (regmap_read(adv7511->regmap_cec,
+			    ADV7511_REG_CEC_TX_LOW_DRV_CNT + offset, &cnt)) {
+			err_cnt = 1;
+			status |= CEC_TX_STATUS_ERROR;
+		} else {
+			nack_cnt = cnt & 0xf;
+			if (nack_cnt)
+				status |= CEC_TX_STATUS_NACK;
+			low_drive_cnt = cnt >> 4;
+			if (low_drive_cnt)
+				status |= CEC_TX_STATUS_LOW_DRIVE;
+		}
+		cec_transmit_done(adv7511->cec_adap, status,
+				  0, nack_cnt, low_drive_cnt, err_cnt);
+		return;
+	}
+	if (tx_raw_status & ADV7511_INT1_CEC_TX_READY) {
+		cec_transmit_attempt_done(adv7511->cec_adap, CEC_TX_STATUS_OK);
+		return;
+	}
+}
+
+void adv7511_cec_irq_process(struct adv7511 *adv7511, unsigned int irq1)
+{
+	unsigned int offset = adv7511->type == ADV7533 ?
+					ADV7533_REG_CEC_OFFSET : 0;
+	const u32 irq_tx_mask = ADV7511_INT1_CEC_TX_READY |
+				ADV7511_INT1_CEC_TX_ARBIT_LOST |
+				ADV7511_INT1_CEC_TX_RETRY_TIMEOUT;
+	struct cec_msg msg = {};
+	unsigned int len;
+	unsigned int val;
+	u8 i;
+
+	if (irq1 & irq_tx_mask)
+		adv_cec_tx_raw_status(adv7511, irq1);
+
+	if (!(irq1 & ADV7511_INT1_CEC_RX_READY1))
+		return;
+
+	if (regmap_read(adv7511->regmap_cec,
+			ADV7511_REG_CEC_RX_FRAME_LEN + offset, &len))
+		return;
+
+	msg.len = len & 0x1f;
+
+	if (msg.len > 16)
+		msg.len = 16;
+
+	if (!msg.len)
+		return;
+
+	for (i = 0; i < msg.len; i++) {
+		regmap_read(adv7511->regmap_cec,
+			    i + ADV7511_REG_CEC_RX_FRAME_HDR + offset, &val);
+		msg.msg[i] = val;
+	}
+
+	/* toggle to re-enable rx 1 */
+	regmap_write(adv7511->regmap_cec,
+		     ADV7511_REG_CEC_RX_BUFFERS + offset, 1);
+	regmap_write(adv7511->regmap_cec,
+		     ADV7511_REG_CEC_RX_BUFFERS + offset, 0);
+	cec_received_msg(adv7511->cec_adap, &msg);
+}
+
+static int adv7511_cec_adap_enable(struct cec_adapter *adap, bool enable)
+{
+	struct adv7511 *adv7511 = cec_get_drvdata(adap);
+	unsigned int offset = adv7511->type == ADV7533 ?
+					ADV7533_REG_CEC_OFFSET : 0;
+
+	if (adv7511->i2c_cec == NULL)
+		return -EIO;
+
+	if (!adv7511->cec_enabled_adap && enable) {
+		/* power up cec section */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_CLK_DIV + offset,
+				   0x03, 0x01);
+		/* legacy mode and clear all rx buffers */
+		regmap_write(adv7511->regmap_cec,
+			     ADV7511_REG_CEC_RX_BUFFERS + offset, 0x07);
+		regmap_write(adv7511->regmap_cec,
+			     ADV7511_REG_CEC_RX_BUFFERS + offset, 0);
+		/* initially disable tx */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_TX_ENABLE + offset, 1, 0);
+		/* enabled irqs: */
+		/* tx: ready */
+		/* tx: arbitration lost */
+		/* tx: retry timeout */
+		/* rx: ready 1 */
+		regmap_update_bits(adv7511->regmap,
+				   ADV7511_REG_INT_ENABLE(1), 0x3f,
+				   ADV7511_INT1_CEC_MASK);
+	} else if (adv7511->cec_enabled_adap && !enable) {
+		regmap_update_bits(adv7511->regmap,
+				   ADV7511_REG_INT_ENABLE(1), 0x3f, 0);
+		/* disable address mask 1-3 */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
+				   0x70, 0x00);
+		/* power down cec section */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_CLK_DIV + offset,
+				   0x03, 0x00);
+		adv7511->cec_valid_addrs = 0;
+	}
+	adv7511->cec_enabled_adap = enable;
+	return 0;
+}
+
+static int adv7511_cec_adap_log_addr(struct cec_adapter *adap, u8 addr)
+{
+	struct adv7511 *adv7511 = cec_get_drvdata(adap);
+	unsigned int offset = adv7511->type == ADV7533 ?
+					ADV7533_REG_CEC_OFFSET : 0;
+	unsigned int i, free_idx = ADV7511_MAX_ADDRS;
+
+	if (!adv7511->cec_enabled_adap)
+		return addr == CEC_LOG_ADDR_INVALID ? 0 : -EIO;
+
+	if (addr == CEC_LOG_ADDR_INVALID) {
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
+				   0x70, 0);
+		adv7511->cec_valid_addrs = 0;
+		return 0;
+	}
+
+	for (i = 0; i < ADV7511_MAX_ADDRS; i++) {
+		bool is_valid = adv7511->cec_valid_addrs & (1 << i);
+
+		if (free_idx == ADV7511_MAX_ADDRS && !is_valid)
+			free_idx = i;
+		if (is_valid && adv7511->cec_addr[i] == addr)
+			return 0;
+	}
+	if (i == ADV7511_MAX_ADDRS) {
+		i = free_idx;
+		if (i == ADV7511_MAX_ADDRS)
+			return -ENXIO;
+	}
+	adv7511->cec_addr[i] = addr;
+	adv7511->cec_valid_addrs |= 1 << i;
+
+	switch (i) {
+	case 0:
+		/* enable address mask 0 */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
+				   0x10, 0x10);
+		/* set address for mask 0 */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_LOG_ADDR_0_1 + offset,
+				   0x0f, addr);
+		break;
+	case 1:
+		/* enable address mask 1 */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
+				   0x20, 0x20);
+		/* set address for mask 1 */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_LOG_ADDR_0_1 + offset,
+				   0xf0, addr << 4);
+		break;
+	case 2:
+		/* enable address mask 2 */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_LOG_ADDR_MASK + offset,
+				   0x40, 0x40);
+		/* set address for mask 1 */
+		regmap_update_bits(adv7511->regmap_cec,
+				   ADV7511_REG_CEC_LOG_ADDR_2 + offset,
+				   0x0f, addr);
+		break;
+	}
+	return 0;
+}
+
+static int adv7511_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
+				     u32 signal_free_time, struct cec_msg *msg)
+{
+	struct adv7511 *adv7511 = cec_get_drvdata(adap);
+	unsigned int offset = adv7511->type == ADV7533 ?
+					ADV7533_REG_CEC_OFFSET : 0;
+	u8 len = msg->len;
+	unsigned int i;
+
+	/*
+	 * The number of retries is the number of attempts - 1, but retry
+	 * at least once. It's not clear if a value of 0 is allowed, so
+	 * let's do at least one retry.
+	 */
+	regmap_update_bits(adv7511->regmap_cec,
+			   ADV7511_REG_CEC_TX_RETRY + offset,
+			   0x70, max(1, attempts - 1) << 4);
+
+	/* blocking, clear cec tx irq status */
+	regmap_update_bits(adv7511->regmap, ADV7511_REG_INT(1), 0x38, 0x38);
+
+	/* write data */
+	for (i = 0; i < len; i++)
+		regmap_write(adv7511->regmap_cec,
+			     i + ADV7511_REG_CEC_TX_FRAME_HDR + offset,
+			     msg->msg[i]);
+
+	/* set length (data + header) */
+	regmap_write(adv7511->regmap_cec,
+		     ADV7511_REG_CEC_TX_FRAME_LEN + offset, len);
+	/* start transmit, enable tx */
+	regmap_write(adv7511->regmap_cec,
+		     ADV7511_REG_CEC_TX_ENABLE + offset, 0x01);
+	return 0;
+}
+
+static const struct cec_adap_ops adv7511_cec_adap_ops = {
+	.adap_enable = adv7511_cec_adap_enable,
+	.adap_log_addr = adv7511_cec_adap_log_addr,
+	.adap_transmit = adv7511_cec_adap_transmit,
+};
+
+static int adv7511_cec_parse_dt(struct device *dev, struct adv7511 *adv7511)
+{
+	adv7511->cec_clk = devm_clk_get(dev, "cec");
+	if (IS_ERR(adv7511->cec_clk)) {
+		int ret = PTR_ERR(adv7511->cec_clk);
+
+		adv7511->cec_clk = NULL;
+		return ret;
+	}
+	clk_prepare_enable(adv7511->cec_clk);
+	adv7511->cec_clk_freq = clk_get_rate(adv7511->cec_clk);
+	return 0;
+}
+
+int adv7511_cec_init(struct device *dev, struct adv7511 *adv7511,
+		     unsigned int offset)
+{
+	int ret = adv7511_cec_parse_dt(dev, adv7511);
+
+	if (ret)
+		return ret;
+
+	adv7511->cec_adap = cec_allocate_adapter(&adv7511_cec_adap_ops,
+		adv7511, dev_name(dev), CEC_CAP_DEFAULTS, ADV7511_MAX_ADDRS);
+	if (IS_ERR(adv7511->cec_adap))
+		return PTR_ERR(adv7511->cec_adap);
+
+	regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL + offset, 0);
+	/* cec soft reset */
+	regmap_write(adv7511->regmap_cec,
+		     ADV7511_REG_CEC_SOFT_RESET + offset, 0x01);
+	regmap_write(adv7511->regmap_cec,
+		     ADV7511_REG_CEC_SOFT_RESET + offset, 0x00);
+
+	/* legacy mode */
+	regmap_write(adv7511->regmap_cec,
+		     ADV7511_REG_CEC_RX_BUFFERS + offset, 0x00);
+
+	regmap_write(adv7511->regmap_cec,
+		     ADV7511_REG_CEC_CLK_DIV + offset,
+		     ((adv7511->cec_clk_freq / 750000) - 1) << 2);
+
+	ret = cec_register_adapter(adv7511->cec_adap, dev);
+	if (ret) {
+		cec_delete_adapter(adv7511->cec_adap);
+		adv7511->cec_adap = NULL;
+	}
+	return ret;
+}
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
index b2431aee7887..3a33075dbb22 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
@@ -11,12 +11,15 @@
 #include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/slab.h>
+#include <linux/clk.h>
 
 #include <drm/drmP.h>
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_edid.h>
 
+#include <media/cec.h>
+
 #include "adv7511.h"
 
 /* ADI recommended values for proper operation. */
@@ -339,8 +342,10 @@ static void __adv7511_power_on(struct adv7511 *adv7511)
 		 */
 		regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(0),
 			     ADV7511_INT0_EDID_READY | ADV7511_INT0_HPD);
-		regmap_write(adv7511->regmap, ADV7511_REG_INT_ENABLE(1),
-			     ADV7511_INT1_DDC_ERROR);
+		regmap_update_bits(adv7511->regmap,
+				   ADV7511_REG_INT_ENABLE(1),
+				   ADV7511_INT1_DDC_ERROR,
+				   ADV7511_INT1_DDC_ERROR);
 	}
 
 	/*
@@ -376,6 +381,9 @@ static void __adv7511_power_off(struct adv7511 *adv7511)
 	regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER,
 			   ADV7511_POWER_POWER_DOWN,
 			   ADV7511_POWER_POWER_DOWN);
+	regmap_update_bits(adv7511->regmap,
+			   ADV7511_REG_INT_ENABLE(1),
+			   ADV7511_INT1_DDC_ERROR, 0);
 	regcache_mark_dirty(adv7511->regmap);
 }
 
@@ -426,6 +434,8 @@ static void adv7511_hpd_work(struct work_struct *work)
 
 	if (adv7511->connector.status != status) {
 		adv7511->connector.status = status;
+		if (status == connector_status_disconnected)
+			cec_phys_addr_invalidate(adv7511->cec_adap);
 		drm_kms_helper_hotplug_event(adv7511->connector.dev);
 	}
 }
@@ -456,6 +466,10 @@ static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd)
 			wake_up_all(&adv7511->wq);
 	}
 
+#ifdef CONFIG_DRM_I2C_ADV7511_CEC
+	adv7511_cec_irq_process(adv7511, irq1);
+#endif
+
 	return 0;
 }
 
@@ -599,6 +613,8 @@ static int adv7511_get_modes(struct adv7511 *adv7511,
 
 	adv7511_set_config_csc(adv7511, connector, adv7511->rgb);
 
+	cec_s_phys_addr_from_edid(adv7511->cec_adap, edid);
+
 	return count;
 }
 
@@ -919,6 +935,65 @@ static void adv7511_uninit_regulators(struct adv7511 *adv)
 	regulator_bulk_disable(adv->num_supplies, adv->supplies);
 }
 
+static bool adv7511_cec_register_volatile(struct device *dev, unsigned int reg)
+{
+	struct i2c_client *i2c = to_i2c_client(dev);
+	struct adv7511 *adv7511 = i2c_get_clientdata(i2c);
+
+	if (adv7511->type == ADV7533)
+		reg -= ADV7533_REG_CEC_OFFSET;
+
+	switch (reg) {
+	case ADV7511_REG_CEC_RX_FRAME_HDR:
+	case ADV7511_REG_CEC_RX_FRAME_DATA0...
+		ADV7511_REG_CEC_RX_FRAME_DATA0 + 14:
+	case ADV7511_REG_CEC_RX_FRAME_LEN:
+	case ADV7511_REG_CEC_RX_BUFFERS:
+	case ADV7511_REG_CEC_TX_LOW_DRV_CNT:
+		return true;
+	}
+
+	return false;
+}
+
+static const struct regmap_config adv7511_cec_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+
+	.max_register = 0xff,
+	.cache_type = REGCACHE_RBTREE,
+	.volatile_reg = adv7511_cec_register_volatile,
+};
+
+static int adv7511_init_cec_regmap(struct adv7511 *adv)
+{
+	int ret;
+
+	adv->i2c_cec = i2c_new_dummy(adv->i2c_main->adapter,
+				     adv->i2c_main->addr - 1);
+	if (!adv->i2c_cec)
+		return -ENOMEM;
+	i2c_set_clientdata(adv->i2c_cec, adv);
+
+	adv->regmap_cec = devm_regmap_init_i2c(adv->i2c_cec,
+					&adv7511_cec_regmap_config);
+	if (IS_ERR(adv->regmap_cec)) {
+		ret = PTR_ERR(adv->regmap_cec);
+		goto err;
+	}
+
+	if (adv->type == ADV7533) {
+		ret = adv7533_patch_cec_registers(adv);
+		if (ret)
+			goto err;
+	}
+
+	return 0;
+err:
+	i2c_unregister_device(adv->i2c_cec);
+	return ret;
+}
+
 static int adv7511_parse_dt(struct device_node *np,
 			    struct adv7511_link_config *config)
 {
@@ -1009,6 +1084,7 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
 	struct device *dev = &i2c->dev;
 	unsigned int main_i2c_addr = i2c->addr << 1;
 	unsigned int edid_i2c_addr = main_i2c_addr + 4;
+	unsigned int offset;
 	unsigned int val;
 	int ret;
 
@@ -1092,11 +1168,9 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
 		goto uninit_regulators;
 	}
 
-	if (adv7511->type == ADV7533) {
-		ret = adv7533_init_cec(adv7511);
-		if (ret)
-			goto err_i2c_unregister_edid;
-	}
+	ret = adv7511_init_cec_regmap(adv7511);
+	if (ret)
+		goto err_i2c_unregister_edid;
 
 	INIT_WORK(&adv7511->hpd_work, adv7511_hpd_work);
 
@@ -1111,10 +1185,6 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
 			goto err_unregister_cec;
 	}
 
-	/* CEC is unused for now */
-	regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL,
-		     ADV7511_CEC_CTRL_POWER_DOWN);
-
 	adv7511_power_off(adv7511);
 
 	i2c_set_clientdata(i2c, adv7511);
@@ -1129,10 +1199,23 @@ static int adv7511_probe(struct i2c_client *i2c, const struct i2c_device_id *id)
 
 	adv7511_audio_init(dev, adv7511);
 
+	offset = adv7511->type == ADV7533 ? ADV7533_REG_CEC_OFFSET : 0;
+
+#ifdef CONFIG_DRM_I2C_ADV7511_CEC
+	ret = adv7511_cec_init(dev, adv7511, offset);
+	if (ret)
+		goto err_unregister_cec;
+#else
+	regmap_write(adv7511->regmap, ADV7511_REG_CEC_CTRL + offset,
+		     ADV7511_CEC_CTRL_POWER_DOWN);
+#endif
+
 	return 0;
 
 err_unregister_cec:
-	adv7533_uninit_cec(adv7511);
+	i2c_unregister_device(adv7511->i2c_cec);
+	if (adv7511->cec_clk)
+		clk_disable_unprepare(adv7511->cec_clk);
 err_i2c_unregister_edid:
 	i2c_unregister_device(adv7511->i2c_edid);
 uninit_regulators:
@@ -1145,10 +1228,11 @@ static int adv7511_remove(struct i2c_client *i2c)
 {
 	struct adv7511 *adv7511 = i2c_get_clientdata(i2c);
 
-	if (adv7511->type == ADV7533) {
+	if (adv7511->type == ADV7533)
 		adv7533_detach_dsi(adv7511);
-		adv7533_uninit_cec(adv7511);
-	}
+	i2c_unregister_device(adv7511->i2c_cec);
+	if (adv7511->cec_clk)
+		clk_disable_unprepare(adv7511->cec_clk);
 
 	adv7511_uninit_regulators(adv7511);
 
@@ -1156,6 +1240,8 @@ static int adv7511_remove(struct i2c_client *i2c)
 
 	adv7511_audio_exit(adv7511);
 
+	cec_unregister_adapter(adv7511->cec_adap);
+
 	i2c_unregister_device(adv7511->i2c_edid);
 
 	kfree(adv7511->edid);
diff --git a/drivers/gpu/drm/bridge/adv7511/adv7533.c b/drivers/gpu/drm/bridge/adv7511/adv7533.c
index ac804f81e2f6..185b6d842166 100644
--- a/drivers/gpu/drm/bridge/adv7511/adv7533.c
+++ b/drivers/gpu/drm/bridge/adv7511/adv7533.c
@@ -32,14 +32,6 @@ static const struct reg_sequence adv7533_cec_fixed_registers[] = {
 	{ 0x05, 0xc8 },
 };
 
-static const struct regmap_config adv7533_cec_regmap_config = {
-	.reg_bits = 8,
-	.val_bits = 8,
-
-	.max_register = 0xff,
-	.cache_type = REGCACHE_RBTREE,
-};
-
 static void adv7511_dsi_config_timing_gen(struct adv7511 *adv)
 {
 	struct mipi_dsi_device *dsi = adv->dsi;
@@ -145,37 +137,11 @@ int adv7533_patch_registers(struct adv7511 *adv)
 				     ARRAY_SIZE(adv7533_fixed_registers));
 }
 
-void adv7533_uninit_cec(struct adv7511 *adv)
-{
-	i2c_unregister_device(adv->i2c_cec);
-}
-
-int adv7533_init_cec(struct adv7511 *adv)
+int adv7533_patch_cec_registers(struct adv7511 *adv)
 {
-	int ret;
-
-	adv->i2c_cec = i2c_new_dummy(adv->i2c_main->adapter,
-				     adv->i2c_main->addr - 1);
-	if (!adv->i2c_cec)
-		return -ENOMEM;
-
-	adv->regmap_cec = devm_regmap_init_i2c(adv->i2c_cec,
-					&adv7533_cec_regmap_config);
-	if (IS_ERR(adv->regmap_cec)) {
-		ret = PTR_ERR(adv->regmap_cec);
-		goto err;
-	}
-
-	ret = regmap_register_patch(adv->regmap_cec,
+	return regmap_register_patch(adv->regmap_cec,
 				    adv7533_cec_fixed_registers,
 				    ARRAY_SIZE(adv7533_cec_fixed_registers));
-	if (ret)
-		goto err;
-
-	return 0;
-err:
-	adv7533_uninit_cec(adv);
-	return ret;
 }
 
 int adv7533_attach_dsi(struct adv7511 *adv)
-- 
2.14.1