[PATCHv2 0/3] tc358743: add CEC support

[PATCHv2 0/3] tc358743: add CEC support

[Hans Verkuil]

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

This little patch series adds support for CEC to the Toshiba TC358743
HDMI to CSI bridge.

The CEC IP is identical to that of the tc358840 for which I already had
CEC support. So this is effectively the tc358840 CEC code copied to the
tc358743. An RFC version of the tc358840 has been posted to the mailinglist
in the past, but it is still not quite ready to be merged.

Once it is ready for merging I might decide to share the CEC code between the
two drivers, but for now just put it in the tc358743 code.

Tested with a Raspberry Pi 2B, Dave Stevenson's bcm283x camera receiver
driver and an Auvidea tc358743 board.

The first patch is a tiny fix for a potential issue in a stub function,
the other two add the CEC support to the tc358743 driver.

Regards,

	Hans

Changes since v1:

- Add tiny cec.h fix for stub function.
- Don't hardcode the physical address, instead read it from the EDID.


Hans Verkuil (3):
  cec.h: initialize *parent and *port in cec_phys_addr_validate
  tc358743_regs.h: add CEC registers
  tc358743: add CEC support

 drivers/media/i2c/Kconfig         |   8 ++
 drivers/media/i2c/tc358743.c      | 205 ++++++++++++++++++++++++++++++++++++--
 drivers/media/i2c/tc358743_regs.h |  94 ++++++++++++++++-
 include/media/cec.h               |   4 +
 4 files changed, 303 insertions(+), 8 deletions(-)

-- 
2.14.1

[PATCHv2 1/3] cec.h: initialize *parent and *port in cec_phys_addr_validate

[Hans Verkuil]

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

Make sure these values are set to avoid 'uninitialized variable'
warnings. Hasn't happened yet, but better safe than sorry.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
 include/media/cec.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/media/cec.h b/include/media/cec.h
index df6b3bd31284..b96423d7058a 100644
--- a/include/media/cec.h
+++ b/include/media/cec.h
@@ -417,6 +417,10 @@ static inline u16 cec_phys_addr_for_input(u16 phys_addr, u8 input)
 
 static inline int cec_phys_addr_validate(u16 phys_addr, u16 *parent, u16 *port)
 {
+	if (parent)
+		*parent = phys_addr;
+	if (port)
+		*port = 0;
 	return 0;
 }
 
-- 
2.14.1

[PATCHv2 2/3] tc358743_regs.h: add CEC registers

[Hans Verkuil]

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

Add the missing CEC register defines.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
 drivers/media/i2c/tc358743_regs.h | 94 ++++++++++++++++++++++++++++++++++++++-
 1 file changed, 92 insertions(+), 2 deletions(-)

diff --git a/drivers/media/i2c/tc358743_regs.h b/drivers/media/i2c/tc358743_regs.h
index 657ef50f215f..227b46471793 100644
--- a/drivers/media/i2c/tc358743_regs.h
+++ b/drivers/media/i2c/tc358743_regs.h
@@ -193,8 +193,98 @@
 #define CSI_START                             0x0518
 #define MASK_STRT                             0x00000001
 
-#define CECEN                                 0x0600
-#define MASK_CECEN                            0x0001
+/* *** CEC (32 bit) *** */
+#define CECHCLK				      0x0028	/* 16 bits */
+#define MASK_CECHCLK			      (0x7ff << 0)
+
+#define CECLCLK				      0x002a	/* 16 bits */
+#define MASK_CECLCLK			      (0x7ff << 0)
+
+#define CECEN				      0x0600
+#define MASK_CECEN			      0x0001
+
+#define CECADD				      0x0604
+#define CECRST				      0x0608
+#define MASK_CECRESET			      0x0001
+
+#define CECREN				      0x060c
+#define MASK_CECREN			      0x0001
+
+#define CECRCTL1			      0x0614
+#define MASK_CECACKDIS			      (1 << 24)
+#define MASK_CECHNC			      (3 << 20)
+#define MASK_CECLNC			      (7 << 16)
+#define MASK_CECMIN			      (7 << 12)
+#define MASK_CECMAX			      (7 << 8)
+#define MASK_CECDAT			      (7 << 4)
+#define MASK_CECTOUT			      (3 << 2)
+#define MASK_CECRIHLD			      (1 << 1)
+#define MASK_CECOTH			      (1 << 0)
+
+#define CECRCTL2			      0x0618
+#define MASK_CECSWAV3			      (7 << 12)
+#define MASK_CECSWAV2			      (7 << 8)
+#define MASK_CECSWAV1			      (7 << 4)
+#define MASK_CECSWAV0			      (7 << 0)
+
+#define CECRCTL3			      0x061c
+#define MASK_CECWAV3			      (7 << 20)
+#define MASK_CECWAV2			      (7 << 16)
+#define MASK_CECWAV1			      (7 << 12)
+#define MASK_CECWAV0			      (7 << 8)
+#define MASK_CECACKEI			      (1 << 4)
+#define MASK_CECMINEI			      (1 << 3)
+#define MASK_CECMAXEI			      (1 << 2)
+#define MASK_CECRSTEI			      (1 << 1)
+#define MASK_CECWAVEI			      (1 << 0)
+
+#define CECTEN				      0x0620
+#define MASK_CECTBUSY			      (1 << 1)
+#define MASK_CECTEN			      (1 << 0)
+
+#define CECTCTL				      0x0628
+#define MASK_CECSTRS			      (7 << 20)
+#define MASK_CECSPRD			      (7 << 16)
+#define MASK_CECDTRS			      (7 << 12)
+#define MASK_CECDPRD			      (15 << 8)
+#define MASK_CECBRD			      (1 << 4)
+#define MASK_CECFREE			      (15 << 0)
+
+#define CECRSTAT			      0x062c
+#define MASK_CECRIWA			      (1 << 6)
+#define MASK_CECRIOR			      (1 << 5)
+#define MASK_CECRIACK			      (1 << 4)
+#define MASK_CECRIMIN			      (1 << 3)
+#define MASK_CECRIMAX			      (1 << 2)
+#define MASK_CECRISTA			      (1 << 1)
+#define MASK_CECRIEND			      (1 << 0)
+
+#define CECTSTAT			      0x0630
+#define MASK_CECTIUR			      (1 << 4)
+#define MASK_CECTIACK			      (1 << 3)
+#define MASK_CECTIAL			      (1 << 2)
+#define MASK_CECTIEND			      (1 << 1)
+
+#define CECRBUF1			      0x0634
+#define MASK_CECRACK			      (1 << 9)
+#define MASK_CECEOM			      (1 << 8)
+#define MASK_CECRBYTE			      (0xff << 0)
+
+#define CECTBUF1			      0x0674
+#define MASK_CECTEOM			      (1 << 8)
+#define MASK_CECTBYTE			      (0xff << 0)
+
+#define CECRCTR				      0x06b4
+#define MASK_CECRCTR			      (0x1f << 0)
+
+#define CECIMSK				      0x06c0
+#define MASK_CECTIM			      (1 << 1)
+#define MASK_CECRIM			      (1 << 0)
+
+#define CECICLR				      0x06cc
+#define MASK_CECTICLR			      (1 << 1)
+#define MASK_CECRICLR			      (1 << 0)
+
 
 #define HDMI_INT0                             0x8500
 #define MASK_I_KEY                            0x80
-- 
2.14.1

[PATCHv2 3/3] tc358743: add CEC support

[Hans Verkuil]

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

Add CEC support for the tc358743 HDMI-CSI bridge.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
 drivers/media/i2c/Kconfig    |   8 ++
 drivers/media/i2c/tc358743.c | 205 +++++++++++++++++++++++++++++++++++++++++--
 2 files changed, 207 insertions(+), 6 deletions(-)

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 94153895fcd4..47113774a297 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -354,6 +354,14 @@ config VIDEO_TC358743
 	  To compile this driver as a module, choose M here: the
 	  module will be called tc358743.
 
+config VIDEO_TC358743_CEC
+	bool "Enable Toshiba TC358743 CEC support"
+	depends on VIDEO_TC358743
+	select CEC_CORE
+	---help---
+	  When selected the tc358743 will support the optional
+	  HDMI CEC feature.
+
 config VIDEO_TVP514X
 	tristate "Texas Instruments TVP514x video decoder"
 	depends on VIDEO_V4L2 && I2C
diff --git a/drivers/media/i2c/tc358743.c b/drivers/media/i2c/tc358743.c
index e6f5c363ccab..e1d8eef7055e 100644
--- a/drivers/media/i2c/tc358743.c
+++ b/drivers/media/i2c/tc358743.c
@@ -39,6 +39,7 @@
 #include <linux/workqueue.h>
 #include <linux/v4l2-dv-timings.h>
 #include <linux/hdmi.h>
+#include <media/cec.h>
 #include <media/v4l2-dv-timings.h>
 #include <media/v4l2-device.h>
 #include <media/v4l2-ctrls.h>
@@ -63,6 +64,7 @@ MODULE_LICENSE("GPL");
 
 #define I2C_MAX_XFER_SIZE  (EDID_BLOCK_SIZE + 2)
 
+#define POLL_INTERVAL_CEC_MS	10
 #define POLL_INTERVAL_MS	1000
 
 static const struct v4l2_dv_timings_cap tc358743_timings_cap = {
@@ -106,6 +108,8 @@ struct tc358743_state {
 	u8 csi_lanes_in_use;
 
 	struct gpio_desc *reset_gpio;
+
+	struct cec_adapter *cec_adap;
 };
 
 static void tc358743_enable_interrupts(struct v4l2_subdev *sd,
@@ -595,6 +599,7 @@ static void tc358743_set_ref_clk(struct v4l2_subdev *sd)
 	struct tc358743_platform_data *pdata = &state->pdata;
 	u32 sys_freq;
 	u32 lockdet_ref;
+	u32 cec_freq;
 	u16 fh_min;
 	u16 fh_max;
 
@@ -626,6 +631,15 @@ static void tc358743_set_ref_clk(struct v4l2_subdev *sd)
 	i2c_wr8_and_or(sd, NCO_F0_MOD, ~MASK_NCO_F0_MOD,
 			(pdata->refclk_hz == 27000000) ?
 			MASK_NCO_F0_MOD_27MHZ : 0x0);
+
+	/*
+	 * Trial and error suggests that the default register value
+	 * of 656 is for a 42 MHz reference clock. Use that to derive
+	 * a new value based on the actual reference clock.
+	 */
+	cec_freq = (656 * sys_freq) / 4200;
+	i2c_wr16(sd, CECHCLK, cec_freq);
+	i2c_wr16(sd, CECLCLK, cec_freq);
 }
 
 static void tc358743_set_csi_color_space(struct v4l2_subdev *sd)
@@ -814,11 +828,17 @@ static void tc358743_initial_setup(struct v4l2_subdev *sd)
 	struct tc358743_state *state = to_state(sd);
 	struct tc358743_platform_data *pdata = &state->pdata;
 
-	/* CEC and IR are not supported by this driver */
-	i2c_wr16_and_or(sd, SYSCTL, ~(MASK_CECRST | MASK_IRRST),
-			(MASK_CECRST | MASK_IRRST));
+	/*
+	 * IR is not supported by this driver.
+	 * CEC is only enabled if needed.
+	 */
+	i2c_wr16_and_or(sd, SYSCTL, ~(MASK_IRRST | MASK_CECRST),
+				     (MASK_IRRST | MASK_CECRST));
 
 	tc358743_reset(sd, MASK_CTXRST | MASK_HDMIRST);
+#ifdef CONFIG_VIDEO_TC358743_CEC
+	tc358743_reset(sd, MASK_CECRST);
+#endif
 	tc358743_sleep_mode(sd, false);
 
 	i2c_wr16(sd, FIFOCTL, pdata->fifo_level);
@@ -842,6 +862,133 @@ static void tc358743_initial_setup(struct v4l2_subdev *sd)
 	i2c_wr8(sd, VOUT_SET3, MASK_VOUT_EXTCNT);
 }
 
+/* --------------- CEC --------------- */
+
+#ifdef CONFIG_VIDEO_TC358743_CEC
+static int tc358743_cec_adap_enable(struct cec_adapter *adap, bool enable)
+{
+	struct tc358743_state *state = adap->priv;
+	struct v4l2_subdev *sd = &state->sd;
+
+	i2c_wr32(sd, CECIMSK, enable ? MASK_CECTIM | MASK_CECRIM : 0);
+	i2c_wr32(sd, CECICLR, MASK_CECTICLR | MASK_CECRICLR);
+	i2c_wr32(sd, CECEN, enable);
+	if (enable)
+		i2c_wr32(sd, CECREN, MASK_CECREN);
+	return 0;
+}
+
+static int tc358743_cec_adap_monitor_all_enable(struct cec_adapter *adap,
+						bool enable)
+{
+	struct tc358743_state *state = adap->priv;
+	struct v4l2_subdev *sd = &state->sd;
+	u32 reg;
+
+	reg = i2c_rd32(sd, CECRCTL1);
+	if (enable)
+		reg |= MASK_CECOTH;
+	else
+		reg &= ~MASK_CECOTH;
+	i2c_wr32(sd, CECRCTL1, reg);
+	return 0;
+}
+
+static int tc358743_cec_adap_log_addr(struct cec_adapter *adap, u8 log_addr)
+{
+	struct tc358743_state *state = adap->priv;
+	struct v4l2_subdev *sd = &state->sd;
+	unsigned int la = 0;
+
+	if (log_addr != CEC_LOG_ADDR_INVALID) {
+		la = i2c_rd32(sd, CECADD);
+		la |= 1 << log_addr;
+	}
+	i2c_wr32(sd, CECADD, la);
+	return 0;
+}
+
+static int tc358743_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
+				   u32 signal_free_time, struct cec_msg *msg)
+{
+	struct tc358743_state *state = adap->priv;
+	struct v4l2_subdev *sd = &state->sd;
+	unsigned int i;
+
+	i2c_wr32(sd, CECTCTL,
+		 (cec_msg_is_broadcast(msg) ? MASK_CECBRD : 0) |
+		 (signal_free_time - 1));
+	for (i = 0; i < msg->len; i++)
+		i2c_wr32(sd, CECTBUF1 + i * 4,
+			msg->msg[i] | ((i == msg->len - 1) ? MASK_CECTEOM : 0));
+	i2c_wr32(sd, CECTEN, MASK_CECTEN);
+	return 0;
+}
+
+static const struct cec_adap_ops tc358743_cec_adap_ops = {
+	.adap_enable = tc358743_cec_adap_enable,
+	.adap_log_addr = tc358743_cec_adap_log_addr,
+	.adap_transmit = tc358743_cec_adap_transmit,
+	.adap_monitor_all_enable = tc358743_cec_adap_monitor_all_enable,
+};
+
+static void tc358743_cec_isr(struct v4l2_subdev *sd, u16 intstatus,
+			     bool *handled)
+{
+	struct tc358743_state *state = to_state(sd);
+	unsigned int cec_rxint, cec_txint;
+	unsigned int clr = 0;
+
+	cec_rxint = i2c_rd32(sd, CECRSTAT);
+	cec_txint = i2c_rd32(sd, CECTSTAT);
+
+	if (intstatus & MASK_CEC_RINT)
+		clr |= MASK_CECRICLR;
+	if (intstatus & MASK_CEC_TINT)
+		clr |= MASK_CECTICLR;
+	i2c_wr32(sd, CECICLR, clr);
+
+	if ((intstatus & MASK_CEC_TINT) && cec_txint) {
+		if (cec_txint & MASK_CECTIEND)
+			cec_transmit_attempt_done(state->cec_adap,
+						  CEC_TX_STATUS_OK);
+		else if (cec_txint & MASK_CECTIAL)
+			cec_transmit_attempt_done(state->cec_adap,
+						  CEC_TX_STATUS_ARB_LOST);
+		else if (cec_txint & MASK_CECTIACK)
+			cec_transmit_attempt_done(state->cec_adap,
+						  CEC_TX_STATUS_NACK);
+		else if (cec_txint & MASK_CECTIUR) {
+			/*
+			 * Not sure when this bit is set. Treat
+			 * it as an error for now.
+			 */
+			cec_transmit_attempt_done(state->cec_adap,
+						  CEC_TX_STATUS_ERROR);
+		}
+		*handled = true;
+	}
+	if ((intstatus & MASK_CEC_RINT) &&
+	    (cec_rxint & MASK_CECRIEND)) {
+		struct cec_msg msg = {};
+		unsigned int i;
+		unsigned int v;
+
+		v = i2c_rd32(sd, CECRCTR);
+		msg.len = v & 0x1f;
+		for (i = 0; i < msg.len; i++) {
+			v = i2c_rd32(sd, CECRBUF1 + i * 4);
+			msg.msg[i] = v & 0xff;
+		}
+		cec_received_msg(state->cec_adap, &msg);
+		*handled = true;
+	}
+	i2c_wr16(sd, INTSTATUS,
+		 intstatus & (MASK_CEC_RINT | MASK_CEC_TINT));
+}
+
+#endif
+
 /* --------------- IRQ --------------- */
 
 static void tc358743_format_change(struct v4l2_subdev *sd)
@@ -1296,6 +1443,15 @@ static int tc358743_isr(struct v4l2_subdev *sd, u32 status, bool *handled)
 		intstatus &= ~MASK_HDMI_INT;
 	}
 
+#ifdef CONFIG_VIDEO_TC358743_CEC
+	if (intstatus & (MASK_CEC_RINT | MASK_CEC_TINT)) {
+		tc358743_cec_isr(sd, intstatus, handled);
+		i2c_wr16(sd, INTSTATUS,
+			 intstatus & (MASK_CEC_RINT | MASK_CEC_TINT));
+		intstatus &= ~(MASK_CEC_RINT | MASK_CEC_TINT);
+	}
+#endif
+
 	if (intstatus & MASK_CSI_INT) {
 		u32 csi_int = i2c_rd32(sd, CSI_INT);
 
@@ -1328,10 +1484,15 @@ static irqreturn_t tc358743_irq_handler(int irq, void *dev_id)
 static void tc358743_irq_poll_timer(unsigned long arg)
 {
 	struct tc358743_state *state = (struct tc358743_state *)arg;
+	unsigned int msecs;
 
 	schedule_work(&state->work_i2c_poll);
-
-	mod_timer(&state->timer, jiffies + msecs_to_jiffies(POLL_INTERVAL_MS));
+	/*
+	 * If CEC is present, then we need to poll more frequently,
+	 * otherwise we will miss CEC messages.
+	 */
+	msecs = state->cec_adap ? POLL_INTERVAL_CEC_MS : POLL_INTERVAL_MS;
+	mod_timer(&state->timer, jiffies + msecs_to_jiffies(msecs));
 }
 
 static void tc358743_work_i2c_poll(struct work_struct *work)
@@ -1621,6 +1782,8 @@ static int tc358743_s_edid(struct v4l2_subdev *sd,
 {
 	struct tc358743_state *state = to_state(sd);
 	u16 edid_len = edid->blocks * EDID_BLOCK_SIZE;
+	u16 pa;
+	int err;
 	int i;
 
 	v4l2_dbg(2, debug, sd, "%s, pad %d, start block %d, blocks %d\n",
@@ -1638,6 +1801,12 @@ static int tc358743_s_edid(struct v4l2_subdev *sd,
 		edid->blocks = EDID_NUM_BLOCKS_MAX;
 		return -E2BIG;
 	}
+	pa = cec_get_edid_phys_addr(edid->edid, edid->blocks * 128, NULL);
+	err = cec_phys_addr_validate(pa, &pa, NULL);
+	if (err)
+		return err;
+
+	cec_phys_addr_invalidate(state->cec_adap);
 
 	tc358743_disable_edid(sd);
 
@@ -1654,6 +1823,8 @@ static int tc358743_s_edid(struct v4l2_subdev *sd,
 
 	state->edid_blocks_written = edid->blocks;
 
+	cec_s_phys_addr(state->cec_adap, pa, false);
+
 	if (tx_5v_power_present(sd))
 		tc358743_enable_edid(sd);
 
@@ -1867,6 +2038,7 @@ static int tc358743_probe(struct i2c_client *client,
 	struct tc358743_state *state;
 	struct tc358743_platform_data *pdata = client->dev.platform_data;
 	struct v4l2_subdev *sd;
+	u16 irq_mask = MASK_HDMI_MSK | MASK_CSI_MSK;
 	int err;
 
 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
@@ -1945,6 +2117,17 @@ static int tc358743_probe(struct i2c_client *client,
 	INIT_DELAYED_WORK(&state->delayed_work_enable_hotplug,
 			tc358743_delayed_work_enable_hotplug);
 
+#ifdef CONFIG_VIDEO_TC358743_CEC
+	state->cec_adap = cec_allocate_adapter(&tc358743_cec_adap_ops,
+		state, dev_name(&client->dev),
+		CEC_CAP_DEFAULTS | CEC_CAP_MONITOR_ALL, CEC_MAX_LOG_ADDRS);
+	if (IS_ERR(state->cec_adap)) {
+		err = state->cec_adap ? PTR_ERR(state->cec_adap) : -ENOMEM;
+		goto err_hdl;
+	}
+	irq_mask |= MASK_CEC_RMSK | MASK_CEC_TMSK;
+#endif
+
 	tc358743_initial_setup(sd);
 
 	tc358743_s_dv_timings(sd, &default_timing);
@@ -1971,8 +2154,16 @@ static int tc358743_probe(struct i2c_client *client,
 		add_timer(&state->timer);
 	}
 
+	err = cec_register_adapter(state->cec_adap, &client->dev);
+	if (err < 0) {
+		pr_err("%s: failed to register the cec device\n", __func__);
+		cec_delete_adapter(state->cec_adap);
+		state->cec_adap = NULL;
+		goto err_work_queues;
+	}
+
 	tc358743_enable_interrupts(sd, tx_5v_power_present(sd));
-	i2c_wr16(sd, INTMASK, ~(MASK_HDMI_MSK | MASK_CSI_MSK) & 0xffff);
+	i2c_wr16(sd, INTMASK, ~irq_mask);
 
 	err = v4l2_ctrl_handler_setup(sd->ctrl_handler);
 	if (err)
@@ -1984,6 +2175,7 @@ static int tc358743_probe(struct i2c_client *client,
 	return 0;
 
 err_work_queues:
+	cec_unregister_adapter(state->cec_adap);
 	if (!state->i2c_client->irq)
 		flush_work(&state->work_i2c_poll);
 	cancel_delayed_work(&state->delayed_work_enable_hotplug);
@@ -2004,6 +2196,7 @@ static int tc358743_remove(struct i2c_client *client)
 		flush_work(&state->work_i2c_poll);
 	}
 	cancel_delayed_work(&state->delayed_work_enable_hotplug);
+	cec_unregister_adapter(state->cec_adap);
 	v4l2_async_unregister_subdev(sd);
 	v4l2_device_unregister_subdev(sd);
 	mutex_destroy(&state->confctl_mutex);
-- 
2.14.1