dw-hdmi-qp.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (c) 2021-2022 Rockchip Electronics Co., Ltd.
 * Copyright (c) 2024 Collabora Ltd.
 *
 * Author: Algea Cao <[email protected]>
 * Author: Cristian Ciocaltea <[email protected]>
 */
#include <linux/completion.h>
#include <linux/hdmi.h>
#include <linux/export.h>
#include <linux/i2c.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/workqueue.h>

#include <drm/bridge/dw_hdmi_qp.h>
#include <drm/display/drm_hdmi_helper.h>
#include <drm/display/drm_hdmi_state_helper.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_connector.h>
#include <drm/drm_edid.h>
#include <drm/drm_modes.h>

#include <sound/hdmi-codec.h>

#include "dw-hdmi-qp.h"

#define DDC_CI_ADDR		0x37
#define DDC_SEGMENT_ADDR	0x30

#define HDMI14_MAX_TMDSCLK	340000000

#define SCRAMB_POLL_DELAY_MS	3000

/*
 * Unless otherwise noted, entries in this table are 100% optimization.
 * Values can be obtained from dw_hdmi_qp_compute_n() but that function is
 * slow so we pre-compute values we expect to see.
 *
 * The values for TMDS 25175, 25200, 27000, 54000, 74250 and 148500 kHz are
 * the recommended N values specified in the Audio chapter of the HDMI
 * specification.
 */
static const struct dw_hdmi_audio_tmds_n {
	unsigned long tmds;
	unsigned int n_32k;
	unsigned int n_44k1;
	unsigned int n_48k;
} common_tmds_n_table[] = {
	{ .tmds = 25175000,  .n_32k = 4576,  .n_44k1 = 7007,  .n_48k = 6864, },
	{ .tmds = 25200000,  .n_32k = 4096,  .n_44k1 = 6272,  .n_48k = 6144, },
	{ .tmds = 27000000,  .n_32k = 4096,  .n_44k1 = 6272,  .n_48k = 6144, },
	{ .tmds = 28320000,  .n_32k = 4096,  .n_44k1 = 5586,  .n_48k = 6144, },
	{ .tmds = 30240000,  .n_32k = 4096,  .n_44k1 = 5642,  .n_48k = 6144, },
	{ .tmds = 31500000,  .n_32k = 4096,  .n_44k1 = 5600,  .n_48k = 6144, },
	{ .tmds = 32000000,  .n_32k = 4096,  .n_44k1 = 5733,  .n_48k = 6144, },
	{ .tmds = 33750000,  .n_32k = 4096,  .n_44k1 = 6272,  .n_48k = 6144, },
	{ .tmds = 36000000,  .n_32k = 4096,  .n_44k1 = 5684,  .n_48k = 6144, },
	{ .tmds = 40000000,  .n_32k = 4096,  .n_44k1 = 5733,  .n_48k = 6144, },
	{ .tmds = 49500000,  .n_32k = 4096,  .n_44k1 = 5488,  .n_48k = 6144, },
	{ .tmds = 50000000,  .n_32k = 4096,  .n_44k1 = 5292,  .n_48k = 6144, },
	{ .tmds = 54000000,  .n_32k = 4096,  .n_44k1 = 6272,  .n_48k = 6144, },
	{ .tmds = 65000000,  .n_32k = 4096,  .n_44k1 = 7056,  .n_48k = 6144, },
	{ .tmds = 68250000,  .n_32k = 4096,  .n_44k1 = 5376,  .n_48k = 6144, },
	{ .tmds = 71000000,  .n_32k = 4096,  .n_44k1 = 7056,  .n_48k = 6144, },
	{ .tmds = 72000000,  .n_32k = 4096,  .n_44k1 = 5635,  .n_48k = 6144, },
	{ .tmds = 73250000,  .n_32k = 11648, .n_44k1 = 14112, .n_48k = 6144, },
	{ .tmds = 74250000,  .n_32k = 4096,  .n_44k1 = 6272,  .n_48k = 6144, },
	{ .tmds = 75000000,  .n_32k = 4096,  .n_44k1 = 5880,  .n_48k = 6144, },
	{ .tmds = 78750000,  .n_32k = 4096,  .n_44k1 = 5600,  .n_48k = 6144, },
	{ .tmds = 78800000,  .n_32k = 4096,  .n_44k1 = 5292,  .n_48k = 6144, },
	{ .tmds = 79500000,  .n_32k = 4096,  .n_44k1 = 4704,  .n_48k = 6144, },
	{ .tmds = 83500000,  .n_32k = 4096,  .n_44k1 = 7056,  .n_48k = 6144, },
	{ .tmds = 85500000,  .n_32k = 4096,  .n_44k1 = 5488,  .n_48k = 6144, },
	{ .tmds = 88750000,  .n_32k = 4096,  .n_44k1 = 14112, .n_48k = 6144, },
	{ .tmds = 97750000,  .n_32k = 4096,  .n_44k1 = 14112, .n_48k = 6144, },
	{ .tmds = 101000000, .n_32k = 4096,  .n_44k1 = 7056,  .n_48k = 6144, },
	{ .tmds = 106500000, .n_32k = 4096,  .n_44k1 = 4704,  .n_48k = 6144, },
	{ .tmds = 108000000, .n_32k = 4096,  .n_44k1 = 5684,  .n_48k = 6144, },
	{ .tmds = 115500000, .n_32k = 4096,  .n_44k1 = 5712,  .n_48k = 6144, },
	{ .tmds = 119000000, .n_32k = 4096,  .n_44k1 = 5544,  .n_48k = 6144, },
	{ .tmds = 135000000, .n_32k = 4096,  .n_44k1 = 5488,  .n_48k = 6144, },
	{ .tmds = 146250000, .n_32k = 11648, .n_44k1 = 6272,  .n_48k = 6144, },
	{ .tmds = 148500000, .n_32k = 4096,  .n_44k1 = 6272,  .n_48k = 6144, },
	{ .tmds = 154000000, .n_32k = 4096,  .n_44k1 = 5544,  .n_48k = 6144, },
	{ .tmds = 162000000, .n_32k = 4096,  .n_44k1 = 5684,  .n_48k = 6144, },

	/* For 297 MHz+ HDMI spec have some other rule for setting N */
	{ .tmds = 297000000, .n_32k = 3073,  .n_44k1 = 4704,  .n_48k = 5120, },
	{ .tmds = 594000000, .n_32k = 3073,  .n_44k1 = 9408,  .n_48k = 10240,},

	/* End of table */
	{ .tmds = 0,         .n_32k = 0,     .n_44k1 = 0,     .n_48k = 0,    },
};

/*
 * These are the CTS values as recommended in the Audio chapter of the HDMI
 * specification.
 */
static const struct dw_hdmi_audio_tmds_cts {
	unsigned long tmds;
	unsigned int cts_32k;
	unsigned int cts_44k1;
	unsigned int cts_48k;
} common_tmds_cts_table[] = {
	{ .tmds = 25175000,  .cts_32k = 28125,  .cts_44k1 = 31250,  .cts_48k = 28125,  },
	{ .tmds = 25200000,  .cts_32k = 25200,  .cts_44k1 = 28000,  .cts_48k = 25200,  },
	{ .tmds = 27000000,  .cts_32k = 27000,  .cts_44k1 = 30000,  .cts_48k = 27000,  },
	{ .tmds = 54000000,  .cts_32k = 54000,  .cts_44k1 = 60000,  .cts_48k = 54000,  },
	{ .tmds = 74250000,  .cts_32k = 74250,  .cts_44k1 = 82500,  .cts_48k = 74250,  },
	{ .tmds = 148500000, .cts_32k = 148500, .cts_44k1 = 165000, .cts_48k = 148500, },

	/* End of table */
	{ .tmds = 0,         .cts_32k = 0,      .cts_44k1 = 0,      .cts_48k = 0,      },
};

struct dw_hdmi_qp_i2c {
	struct i2c_adapter	adap;

	struct mutex		lock;	/* used to serialize data transfers */
	struct completion	cmp;
	u8			stat;

	u8			slave_reg;
	bool			is_regaddr;
	bool			is_segment;
};

struct dw_hdmi_qp {
	struct drm_bridge bridge;

	struct device *dev;
	struct dw_hdmi_qp_i2c *i2c;

	struct {
		const struct dw_hdmi_qp_phy_ops *ops;
		void *data;
	} phy;

	struct regmap *regm;

	unsigned long tmds_char_rate;
};

static void dw_hdmi_qp_write(struct dw_hdmi_qp *hdmi, unsigned int val,
			     int offset)
{
	regmap_write(hdmi->regm, offset, val);
}

static unsigned int dw_hdmi_qp_read(struct dw_hdmi_qp *hdmi, int offset)
{
	unsigned int val = 0;

	regmap_read(hdmi->regm, offset, &val);

	return val;
}

static void dw_hdmi_qp_mod(struct dw_hdmi_qp *hdmi, unsigned int data,
			   unsigned int mask, unsigned int reg)
{
	regmap_update_bits(hdmi->regm, reg, mask, data);
}

static struct dw_hdmi_qp *dw_hdmi_qp_from_bridge(struct drm_bridge *bridge)
{
	return container_of(bridge, struct dw_hdmi_qp, bridge);
}

static void dw_hdmi_qp_set_cts_n(struct dw_hdmi_qp *hdmi, unsigned int cts,
				 unsigned int n)
{
	/* Set N */
	dw_hdmi_qp_mod(hdmi, n, AUDPKT_ACR_N_VALUE, AUDPKT_ACR_CONTROL0);

	/* Set CTS */
	if (cts)
		dw_hdmi_qp_mod(hdmi, AUDPKT_ACR_CTS_OVR_EN, AUDPKT_ACR_CTS_OVR_EN_MSK,
			       AUDPKT_ACR_CONTROL1);
	else
		dw_hdmi_qp_mod(hdmi, 0, AUDPKT_ACR_CTS_OVR_EN_MSK,
			       AUDPKT_ACR_CONTROL1);

	dw_hdmi_qp_mod(hdmi, AUDPKT_ACR_CTS_OVR_VAL(cts), AUDPKT_ACR_CTS_OVR_VAL_MSK,
		       AUDPKT_ACR_CONTROL1);
}

static int dw_hdmi_qp_match_tmds_n_table(struct dw_hdmi_qp *hdmi,
					 unsigned long pixel_clk,
					 unsigned long freq)
{
	const struct dw_hdmi_audio_tmds_n *tmds_n = NULL;
	int i;

	for (i = 0; common_tmds_n_table[i].tmds != 0; i++) {
		if (pixel_clk == common_tmds_n_table[i].tmds) {
			tmds_n = &common_tmds_n_table[i];
			break;
		}
	}

	if (!tmds_n)
		return -ENOENT;

	switch (freq) {
	case 32000:
		return tmds_n->n_32k;
	case 44100:
	case 88200:
	case 176400:
		return (freq / 44100) * tmds_n->n_44k1;
	case 48000:
	case 96000:
	case 192000:
		return (freq / 48000) * tmds_n->n_48k;
	default:
		return -ENOENT;
	}
}

static u32 dw_hdmi_qp_audio_math_diff(unsigned int freq, unsigned int n,
				      unsigned int pixel_clk)
{
	u64 cts = mul_u32_u32(pixel_clk, n);

	return do_div(cts, 128 * freq);
}

static unsigned int dw_hdmi_qp_compute_n(struct dw_hdmi_qp *hdmi,
					 unsigned long pixel_clk,
					 unsigned long freq)
{
	unsigned int min_n = DIV_ROUND_UP((128 * freq), 1500);
	unsigned int max_n = (128 * freq) / 300;
	unsigned int ideal_n = (128 * freq) / 1000;
	unsigned int best_n_distance = ideal_n;
	unsigned int best_n = 0;
	u64 best_diff = U64_MAX;
	int n;

	/* If the ideal N could satisfy the audio math, then just take it */
	if (dw_hdmi_qp_audio_math_diff(freq, ideal_n, pixel_clk) == 0)
		return ideal_n;

	for (n = min_n; n <= max_n; n++) {
		u64 diff = dw_hdmi_qp_audio_math_diff(freq, n, pixel_clk);

		if (diff < best_diff ||
		    (diff == best_diff && abs(n - ideal_n) < best_n_distance)) {
			best_n = n;
			best_diff = diff;
			best_n_distance = abs(best_n - ideal_n);
		}

		/*
		 * The best N already satisfy the audio math, and also be
		 * the closest value to ideal N, so just cut the loop.
		 */
		if (best_diff == 0 && (abs(n - ideal_n) > best_n_distance))
			break;
	}

	return best_n;
}

static unsigned int dw_hdmi_qp_find_n(struct dw_hdmi_qp *hdmi, unsigned long pixel_clk,
				      unsigned long sample_rate)
{
	int n = dw_hdmi_qp_match_tmds_n_table(hdmi, pixel_clk, sample_rate);

	if (n > 0)
		return n;

	dev_warn(hdmi->dev, "Rate %lu missing; compute N dynamically\n",
		 pixel_clk);

	return dw_hdmi_qp_compute_n(hdmi, pixel_clk, sample_rate);
}

static unsigned int dw_hdmi_qp_find_cts(struct dw_hdmi_qp *hdmi, unsigned long pixel_clk,
					unsigned long sample_rate)
{
	const struct dw_hdmi_audio_tmds_cts *tmds_cts = NULL;
	int i;

	for (i = 0; common_tmds_cts_table[i].tmds != 0; i++) {
		if (pixel_clk == common_tmds_cts_table[i].tmds) {
			tmds_cts = &common_tmds_cts_table[i];
			break;
		}
	}

	if (!tmds_cts)
		return 0;

	switch (sample_rate) {
	case 32000:
		return tmds_cts->cts_32k;
	case 44100:
	case 88200:
	case 176400:
		return tmds_cts->cts_44k1;
	case 48000:
	case 96000:
	case 192000:
		return tmds_cts->cts_48k;
	default:
		return -ENOENT;
	}
}

static void dw_hdmi_qp_set_audio_interface(struct dw_hdmi_qp *hdmi,
					   struct hdmi_codec_daifmt *fmt,
					   struct hdmi_codec_params *hparms)
{
	u32 conf0 = 0;

	/* Reset the audio data path of the AVP */
	dw_hdmi_qp_write(hdmi, AVP_DATAPATH_PACKET_AUDIO_SWINIT_P, GLOBAL_SWRESET_REQUEST);

	/* Disable AUDS, ACR, AUDI */
	dw_hdmi_qp_mod(hdmi, 0,
		       PKTSCHED_ACR_TX_EN | PKTSCHED_AUDS_TX_EN | PKTSCHED_AUDI_TX_EN,
		       PKTSCHED_PKT_EN);

	/* Clear the audio FIFO */
	dw_hdmi_qp_write(hdmi, AUDIO_FIFO_CLR_P, AUDIO_INTERFACE_CONTROL0);

	/* Select I2S interface as the audio source */
	dw_hdmi_qp_mod(hdmi, AUD_IF_I2S, AUD_IF_SEL_MSK, AUDIO_INTERFACE_CONFIG0);

	/* Enable the active i2s lanes */
	switch (hparms->channels) {
	case 7 ... 8:
		conf0 |= I2S_LINES_EN(3);
		fallthrough;
	case 5 ... 6:
		conf0 |= I2S_LINES_EN(2);
		fallthrough;
	case 3 ... 4:
		conf0 |= I2S_LINES_EN(1);
		fallthrough;
	default:
		conf0 |= I2S_LINES_EN(0);
		break;
	}

	dw_hdmi_qp_mod(hdmi, conf0, I2S_LINES_EN_MSK, AUDIO_INTERFACE_CONFIG0);

	/*
	 * Enable bpcuv generated internally for L-PCM, or received
	 * from stream for NLPCM/HBR.
	 */
	switch (fmt->bit_fmt) {
	case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
		conf0 = (hparms->channels == 8) ? AUD_HBR : AUD_ASP;
		conf0 |= I2S_BPCUV_RCV_EN;
		break;
	default:
		conf0 = AUD_ASP | I2S_BPCUV_RCV_DIS;
		break;
	}

	dw_hdmi_qp_mod(hdmi, conf0, I2S_BPCUV_RCV_MSK | AUD_FORMAT_MSK,
		       AUDIO_INTERFACE_CONFIG0);

	/* Enable audio FIFO auto clear when overflow */
	dw_hdmi_qp_mod(hdmi, AUD_FIFO_INIT_ON_OVF_EN, AUD_FIFO_INIT_ON_OVF_MSK,
		       AUDIO_INTERFACE_CONFIG0);
}

/*
 * When transmitting IEC60958 linear PCM audio, these registers allow to
 * configure the channel status information of all the channel status
 * bits in the IEC60958 frame. For the moment this configuration is only
 * used when the I2S audio interface, General Purpose Audio (GPA),
 * or AHB audio DMA (AHBAUDDMA) interface is active
 * (for S/PDIF interface this information comes from the stream).
 */
static void dw_hdmi_qp_set_channel_status(struct dw_hdmi_qp *hdmi,
					  u8 *channel_status, bool ref2stream)
{
	/*
	 * AUDPKT_CHSTATUS_OVR0: { RSV, RSV, CS1, CS0 }
	 * AUDPKT_CHSTATUS_OVR1: { CS6, CS5, CS4, CS3 }
	 *
	 *      |  7  |  6  |  5  |  4  |  3  |  2  |  1  |  0  |
	 * CS0: |   Mode    |        d        |  c  |  b  |  a  |
	 * CS1: |               Category Code                   |
	 * CS2: |    Channel Number     |     Source Number     |
	 * CS3: |    Clock Accuracy     |     Sample Freq       |
	 * CS4: |    Ori Sample Freq    |     Word Length       |
	 * CS5: |                                   |   CGMS-A  |
	 * CS6~CS23: Reserved
	 *
	 * a: use of channel status block
	 * b: linear PCM identification: 0 for lpcm, 1 for nlpcm
	 * c: copyright information
	 * d: additional format information
	 */

	if (ref2stream)
		channel_status[0] |= IEC958_AES0_NONAUDIO;

	if ((dw_hdmi_qp_read(hdmi, AUDIO_INTERFACE_CONFIG0) & GENMASK(25, 24)) == AUD_HBR) {
		/* fixup cs for HBR */
		channel_status[3] = (channel_status[3] & 0xf0) | IEC958_AES3_CON_FS_768000;
		channel_status[4] = (channel_status[4] & 0x0f) | IEC958_AES4_CON_ORIGFS_NOTID;
	}

	dw_hdmi_qp_write(hdmi, channel_status[0] | (channel_status[1] << 8),
			 AUDPKT_CHSTATUS_OVR0);

	regmap_bulk_write(hdmi->regm, AUDPKT_CHSTATUS_OVR1, &channel_status[3], 1);

	if (ref2stream)
		dw_hdmi_qp_mod(hdmi, 0,
			       AUDPKT_PBIT_FORCE_EN_MASK | AUDPKT_CHSTATUS_OVR_EN_MASK,
			       AUDPKT_CONTROL0);
	else
		dw_hdmi_qp_mod(hdmi, AUDPKT_PBIT_FORCE_EN | AUDPKT_CHSTATUS_OVR_EN,
			       AUDPKT_PBIT_FORCE_EN_MASK | AUDPKT_CHSTATUS_OVR_EN_MASK,
			       AUDPKT_CONTROL0);
}

static void dw_hdmi_qp_set_sample_rate(struct dw_hdmi_qp *hdmi, unsigned long long tmds_char_rate,
				       unsigned int sample_rate)
{
	unsigned int n, cts;

	n = dw_hdmi_qp_find_n(hdmi, tmds_char_rate, sample_rate);
	cts = dw_hdmi_qp_find_cts(hdmi, tmds_char_rate, sample_rate);

	dw_hdmi_qp_set_cts_n(hdmi, cts, n);
}

static int dw_hdmi_qp_audio_enable(struct drm_bridge *bridge,
				   struct drm_connector *connector)
{
	struct dw_hdmi_qp *hdmi = dw_hdmi_qp_from_bridge(bridge);

	if (hdmi->tmds_char_rate)
		dw_hdmi_qp_mod(hdmi, 0, AVP_DATAPATH_PACKET_AUDIO_SWDISABLE, GLOBAL_SWDISABLE);

	return 0;
}

static int dw_hdmi_qp_audio_prepare(struct drm_bridge *bridge,
				    struct drm_connector *connector,
				    struct hdmi_codec_daifmt *fmt,
				    struct hdmi_codec_params *hparms)
{
	struct dw_hdmi_qp *hdmi = dw_hdmi_qp_from_bridge(bridge);
	bool ref2stream = false;

	if (!hdmi->tmds_char_rate)
		return -ENODEV;

	if (fmt->bit_clk_provider | fmt->frame_clk_provider) {
		dev_err(hdmi->dev, "unsupported clock settings\n");
		return -EINVAL;
	}

	if (fmt->bit_fmt == SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE)
		ref2stream = true;

	dw_hdmi_qp_set_audio_interface(hdmi, fmt, hparms);
	dw_hdmi_qp_set_sample_rate(hdmi, hdmi->tmds_char_rate, hparms->sample_rate);
	dw_hdmi_qp_set_channel_status(hdmi, hparms->iec.status, ref2stream);
	drm_atomic_helper_connector_hdmi_update_audio_infoframe(connector, &hparms->cea);

	return 0;
}

static void dw_hdmi_qp_audio_disable_regs(struct dw_hdmi_qp *hdmi)
{
	/*
	 * Keep ACR, AUDI, AUDS packet always on to make SINK device
	 * active for better compatibility and user experience.
	 *
	 * This also fix POP sound on some SINK devices which wakeup
	 * from suspend to active.
	 */
	dw_hdmi_qp_mod(hdmi, I2S_BPCUV_RCV_DIS, I2S_BPCUV_RCV_MSK,
		       AUDIO_INTERFACE_CONFIG0);
	dw_hdmi_qp_mod(hdmi, AUDPKT_PBIT_FORCE_EN | AUDPKT_CHSTATUS_OVR_EN,
		       AUDPKT_PBIT_FORCE_EN_MASK | AUDPKT_CHSTATUS_OVR_EN_MASK,
		       AUDPKT_CONTROL0);

	dw_hdmi_qp_mod(hdmi, AVP_DATAPATH_PACKET_AUDIO_SWDISABLE,
		       AVP_DATAPATH_PACKET_AUDIO_SWDISABLE, GLOBAL_SWDISABLE);
}

static void dw_hdmi_qp_audio_disable(struct drm_bridge *bridge,
				     struct drm_connector *connector)
{
	struct dw_hdmi_qp *hdmi = dw_hdmi_qp_from_bridge(bridge);

	drm_atomic_helper_connector_hdmi_clear_audio_infoframe(connector);

	if (hdmi->tmds_char_rate)
		dw_hdmi_qp_audio_disable_regs(hdmi);
}

static int dw_hdmi_qp_i2c_read(struct dw_hdmi_qp *hdmi,
			       unsigned char *buf, unsigned int length)
{
	struct dw_hdmi_qp_i2c *i2c = hdmi->i2c;
	int stat;

	if (!i2c->is_regaddr) {
		dev_dbg(hdmi->dev, "set read register address to 0\n");
		i2c->slave_reg = 0x00;
		i2c->is_regaddr = true;
	}

	while (length--) {
		reinit_completion(&i2c->cmp);

		dw_hdmi_qp_mod(hdmi, i2c->slave_reg++ << 12, I2CM_ADDR,
			       I2CM_INTERFACE_CONTROL0);

		if (i2c->is_segment)
			dw_hdmi_qp_mod(hdmi, I2CM_EXT_READ, I2CM_WR_MASK,
				       I2CM_INTERFACE_CONTROL0);
		else
			dw_hdmi_qp_mod(hdmi, I2CM_FM_READ, I2CM_WR_MASK,
				       I2CM_INTERFACE_CONTROL0);

		stat = wait_for_completion_timeout(&i2c->cmp, HZ / 10);
		if (!stat) {
			dev_err(hdmi->dev, "i2c read timed out\n");
			dw_hdmi_qp_write(hdmi, 0x01, I2CM_CONTROL0);
			return -EAGAIN;
		}

		/* Check for error condition on the bus */
		if (i2c->stat & I2CM_NACK_RCVD_IRQ) {
			dev_err(hdmi->dev, "i2c read error\n");
			dw_hdmi_qp_write(hdmi, 0x01, I2CM_CONTROL0);
			return -EIO;
		}

		*buf++ = dw_hdmi_qp_read(hdmi, I2CM_INTERFACE_RDDATA_0_3) & 0xff;
		dw_hdmi_qp_mod(hdmi, 0, I2CM_WR_MASK, I2CM_INTERFACE_CONTROL0);
	}

	i2c->is_segment = false;

	return 0;
}

static int dw_hdmi_qp_i2c_write(struct dw_hdmi_qp *hdmi,
				unsigned char *buf, unsigned int length)
{
	struct dw_hdmi_qp_i2c *i2c = hdmi->i2c;
	int stat;

	if (!i2c->is_regaddr) {
		/* Use the first write byte as register address */
		i2c->slave_reg = buf[0];
		length--;
		buf++;
		i2c->is_regaddr = true;
	}

	while (length--) {
		reinit_completion(&i2c->cmp);

		dw_hdmi_qp_write(hdmi, *buf++, I2CM_INTERFACE_WRDATA_0_3);
		dw_hdmi_qp_mod(hdmi, i2c->slave_reg++ << 12, I2CM_ADDR,
			       I2CM_INTERFACE_CONTROL0);
		dw_hdmi_qp_mod(hdmi, I2CM_FM_WRITE, I2CM_WR_MASK,
			       I2CM_INTERFACE_CONTROL0);

		stat = wait_for_completion_timeout(&i2c->cmp, HZ / 10);
		if (!stat) {
			dev_err(hdmi->dev, "i2c write time out!\n");
			dw_hdmi_qp_write(hdmi, 0x01, I2CM_CONTROL0);
			return -EAGAIN;
		}

		/* Check for error condition on the bus */
		if (i2c->stat & I2CM_NACK_RCVD_IRQ) {
			dev_err(hdmi->dev, "i2c write nack!\n");
			dw_hdmi_qp_write(hdmi, 0x01, I2CM_CONTROL0);
			return -EIO;
		}

		dw_hdmi_qp_mod(hdmi, 0, I2CM_WR_MASK, I2CM_INTERFACE_CONTROL0);
	}

	return 0;
}

static int dw_hdmi_qp_i2c_xfer(struct i2c_adapter *adap,
			       struct i2c_msg *msgs, int num)
{
	struct dw_hdmi_qp *hdmi = i2c_get_adapdata(adap);
	struct dw_hdmi_qp_i2c *i2c = hdmi->i2c;
	u8 addr = msgs[0].addr;
	int i, ret = 0;

	if (addr == DDC_CI_ADDR)
		/*
		 * The internal I2C controller does not support the multi-byte
		 * read and write operations needed for DDC/CI.
		 * FIXME: Blacklist the DDC/CI address until we filter out
		 * unsupported I2C operations.
		 */
		return -EOPNOTSUPP;

	for (i = 0; i < num; i++) {
		if (msgs[i].len == 0) {
			dev_err(hdmi->dev,
				"unsupported transfer %d/%d, no data\n",
				i + 1, num);
			return -EOPNOTSUPP;
		}
	}

	guard(mutex)(&i2c->lock);

	/* Unmute DONE and ERROR interrupts */
	dw_hdmi_qp_mod(hdmi, I2CM_NACK_RCVD_MASK_N | I2CM_OP_DONE_MASK_N,
		       I2CM_NACK_RCVD_MASK_N | I2CM_OP_DONE_MASK_N,
		       MAINUNIT_1_INT_MASK_N);

	/* Set slave device address taken from the first I2C message */
	if (addr == DDC_SEGMENT_ADDR && msgs[0].len == 1)
		addr = DDC_ADDR;

	dw_hdmi_qp_mod(hdmi, addr << 5, I2CM_SLVADDR, I2CM_INTERFACE_CONTROL0);

	/* Set slave device register address on transfer */
	i2c->is_regaddr = false;

	/* Set segment pointer for I2C extended read mode operation */
	i2c->is_segment = false;

	for (i = 0; i < num; i++) {
		if (msgs[i].addr == DDC_SEGMENT_ADDR && msgs[i].len == 1) {
			i2c->is_segment = true;
			dw_hdmi_qp_mod(hdmi, DDC_SEGMENT_ADDR, I2CM_SEG_ADDR,
				       I2CM_INTERFACE_CONTROL1);
			dw_hdmi_qp_mod(hdmi, *msgs[i].buf << 7, I2CM_SEG_PTR,
				       I2CM_INTERFACE_CONTROL1);
		} else {
			if (msgs[i].flags & I2C_M_RD)
				ret = dw_hdmi_qp_i2c_read(hdmi, msgs[i].buf,
							  msgs[i].len);
			else
				ret = dw_hdmi_qp_i2c_write(hdmi, msgs[i].buf,
							   msgs[i].len);
		}
		if (ret < 0)
			break;
	}

	if (!ret)
		ret = num;

	/* Mute DONE and ERROR interrupts */
	dw_hdmi_qp_mod(hdmi, 0, I2CM_OP_DONE_MASK_N | I2CM_NACK_RCVD_MASK_N,
		       MAINUNIT_1_INT_MASK_N);

	return ret;
}

static u32 dw_hdmi_qp_i2c_func(struct i2c_adapter *adapter)
{
	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}

static const struct i2c_algorithm dw_hdmi_qp_algorithm = {
	.master_xfer	= dw_hdmi_qp_i2c_xfer,
	.functionality	= dw_hdmi_qp_i2c_func,
};

static struct i2c_adapter *dw_hdmi_qp_i2c_adapter(struct dw_hdmi_qp *hdmi)
{
	struct dw_hdmi_qp_i2c *i2c;
	struct i2c_adapter *adap;
	int ret;

	i2c = devm_kzalloc(hdmi->dev, sizeof(*i2c), GFP_KERNEL);
	if (!i2c)
		return ERR_PTR(-ENOMEM);

	mutex_init(&i2c->lock);
	init_completion(&i2c->cmp);

	adap = &i2c->adap;
	adap->owner = THIS_MODULE;
	adap->dev.parent = hdmi->dev;
	adap->algo = &dw_hdmi_qp_algorithm;
	strscpy(adap->name, "DesignWare HDMI QP", sizeof(adap->name));

	i2c_set_adapdata(adap, hdmi);

	ret = devm_i2c_add_adapter(hdmi->dev, adap);
	if (ret) {
		dev_warn(hdmi->dev, "cannot add %s I2C adapter\n", adap->name);
		devm_kfree(hdmi->dev, i2c);
		return ERR_PTR(ret);
	}

	hdmi->i2c = i2c;
	dev_info(hdmi->dev, "registered %s I2C bus driver\n", adap->name);

	return adap;
}

static int dw_hdmi_qp_config_avi_infoframe(struct dw_hdmi_qp *hdmi,
					   const u8 *buffer, size_t len)
{
	u32 val, i, j;

	if (len != HDMI_INFOFRAME_SIZE(AVI)) {
		dev_err(hdmi->dev, "failed to configure avi infoframe\n");
		return -EINVAL;
	}

	/*
	 * DW HDMI QP IP uses a different byte format from standard AVI info
	 * frames, though generally the bits are in the correct bytes.
	 */
	val = buffer[1] << 8 | buffer[2] << 16;
	dw_hdmi_qp_write(hdmi, val, PKT_AVI_CONTENTS0);

	for (i = 0; i < 4; i++) {
		for (j = 0; j < 4; j++) {
			if (i * 4 + j >= 14)
				break;
			if (!j)
				val = buffer[i * 4 + j + 3];
			val |= buffer[i * 4 + j + 3] << (8 * j);
		}

		dw_hdmi_qp_write(hdmi, val, PKT_AVI_CONTENTS1 + i * 4);
	}

	dw_hdmi_qp_mod(hdmi, 0, PKTSCHED_AVI_FIELDRATE, PKTSCHED_PKT_CONFIG1);

	dw_hdmi_qp_mod(hdmi, PKTSCHED_AVI_TX_EN | PKTSCHED_GCP_TX_EN,
		       PKTSCHED_AVI_TX_EN | PKTSCHED_GCP_TX_EN, PKTSCHED_PKT_EN);

	return 0;
}

static int dw_hdmi_qp_config_drm_infoframe(struct dw_hdmi_qp *hdmi,
					   const u8 *buffer, size_t len)
{
	u32 val, i;

	if (len != HDMI_INFOFRAME_SIZE(DRM)) {
		dev_err(hdmi->dev, "failed to configure drm infoframe\n");
		return -EINVAL;
	}

	dw_hdmi_qp_mod(hdmi, 0, PKTSCHED_DRMI_TX_EN, PKTSCHED_PKT_EN);

	val = buffer[1] << 8 | buffer[2] << 16;
	dw_hdmi_qp_write(hdmi, val, PKT_DRMI_CONTENTS0);

	for (i = 0; i <= buffer[2]; i++) {
		if (i % 4 == 0)
			val = buffer[3 + i];
		val |= buffer[3 + i] << ((i % 4) * 8);

		if ((i % 4 == 3) || i == buffer[2])
			dw_hdmi_qp_write(hdmi, val,
					 PKT_DRMI_CONTENTS1 + ((i / 4) * 4));
	}

	dw_hdmi_qp_mod(hdmi, 0, PKTSCHED_DRMI_FIELDRATE, PKTSCHED_PKT_CONFIG1);
	dw_hdmi_qp_mod(hdmi, PKTSCHED_DRMI_TX_EN, PKTSCHED_DRMI_TX_EN,
		       PKTSCHED_PKT_EN);

	return 0;
}

/*
 * Static values documented in the TRM
 * Different values are only used for debug purposes
 */
#define DW_HDMI_QP_AUDIO_INFOFRAME_HB1	0x1
#define DW_HDMI_QP_AUDIO_INFOFRAME_HB2	0xa

static int dw_hdmi_qp_config_audio_infoframe(struct dw_hdmi_qp *hdmi,
					     const u8 *buffer, size_t len)
{
	/*
	 * AUDI_CONTENTS0: { RSV, HB2, HB1, RSV }
	 * AUDI_CONTENTS1: { PB3, PB2, PB1, PB0 }
	 * AUDI_CONTENTS2: { PB7, PB6, PB5, PB4 }
	 *
	 * PB0: CheckSum
	 * PB1: | CT3    | CT2  | CT1  | CT0  | F13  | CC2 | CC1 | CC0 |
	 * PB2: | F27    | F26  | F25  | SF2  | SF1  | SF0 | SS1 | SS0 |
	 * PB3: | F37    | F36  | F35  | F34  | F33  | F32 | F31 | F30 |
	 * PB4: | CA7    | CA6  | CA5  | CA4  | CA3  | CA2 | CA1 | CA0 |
	 * PB5: | DM_INH | LSV3 | LSV2 | LSV1 | LSV0 | F52 | F51 | F50 |
	 * PB6~PB10: Reserved
	 *
	 * AUDI_CONTENTS0 default value defined by HDMI specification,
	 * and shall only be changed for debug purposes.
	 */
	u32 header_bytes = (DW_HDMI_QP_AUDIO_INFOFRAME_HB1 << 8) |
			  (DW_HDMI_QP_AUDIO_INFOFRAME_HB2 << 16);

	regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS0, &header_bytes, 1);
	regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS1, &buffer[3], 1);
	regmap_bulk_write(hdmi->regm, PKT_AUDI_CONTENTS2, &buffer[4], 1);

	/* Enable ACR, AUDI, AMD */
	dw_hdmi_qp_mod(hdmi,
		       PKTSCHED_ACR_TX_EN | PKTSCHED_AUDI_TX_EN | PKTSCHED_AMD_TX_EN,
		       PKTSCHED_ACR_TX_EN | PKTSCHED_AUDI_TX_EN | PKTSCHED_AMD_TX_EN,
		       PKTSCHED_PKT_EN);

	/* Enable AUDS */
	dw_hdmi_qp_mod(hdmi, PKTSCHED_AUDS_TX_EN, PKTSCHED_AUDS_TX_EN, PKTSCHED_PKT_EN);

	return 0;
}

static void dw_hdmi_qp_bridge_atomic_enable(struct drm_bridge *bridge,
					    struct drm_atomic_state *state)
{
	struct dw_hdmi_qp *hdmi = bridge->driver_private;
	struct drm_connector_state *conn_state;
	struct drm_connector *connector;
	unsigned int op_mode;

	connector = drm_atomic_get_new_connector_for_encoder(state, bridge->encoder);
	if (WARN_ON(!connector))
		return;

	conn_state = drm_atomic_get_new_connector_state(state, connector);
	if (WARN_ON(!conn_state))
		return;

	if (connector->display_info.is_hdmi) {
		dev_dbg(hdmi->dev, "%s mode=HDMI rate=%llu\n",
			__func__, conn_state->hdmi.tmds_char_rate);
		op_mode = 0;
		hdmi->tmds_char_rate = conn_state->hdmi.tmds_char_rate;
	} else {
		dev_dbg(hdmi->dev, "%s mode=DVI\n", __func__);
		op_mode = OPMODE_DVI;
	}

	hdmi->phy.ops->init(hdmi, hdmi->phy.data);

	dw_hdmi_qp_mod(hdmi, HDCP2_BYPASS, HDCP2_BYPASS, HDCP2LOGIC_CONFIG0);
	dw_hdmi_qp_mod(hdmi, op_mode, OPMODE_DVI, LINK_CONFIG0);

	drm_atomic_helper_connector_hdmi_update_infoframes(connector, state);
}

static void dw_hdmi_qp_bridge_atomic_disable(struct drm_bridge *bridge,
					     struct drm_atomic_state *state)
{
	struct dw_hdmi_qp *hdmi = bridge->driver_private;

	hdmi->tmds_char_rate = 0;

	hdmi->phy.ops->disable(hdmi, hdmi->phy.data);
}

static enum drm_connector_status
dw_hdmi_qp_bridge_detect(struct drm_bridge *bridge, struct drm_connector *connector)
{
	struct dw_hdmi_qp *hdmi = bridge->driver_private;

	return hdmi->phy.ops->read_hpd(hdmi, hdmi->phy.data);
}

static const struct drm_edid *
dw_hdmi_qp_bridge_edid_read(struct drm_bridge *bridge,
			    struct drm_connector *connector)
{
	struct dw_hdmi_qp *hdmi = bridge->driver_private;
	const struct drm_edid *drm_edid;

	drm_edid = drm_edid_read_ddc(connector, bridge->ddc);
	if (!drm_edid)
		dev_dbg(hdmi->dev, "failed to get edid\n");

	return drm_edid;
}

static enum drm_mode_status
dw_hdmi_qp_bridge_tmds_char_rate_valid(const struct drm_bridge *bridge,
				       const struct drm_display_mode *mode,
				       unsigned long long rate)
{
	struct dw_hdmi_qp *hdmi = bridge->driver_private;

	if (rate > HDMI14_MAX_TMDSCLK) {
		dev_dbg(hdmi->dev, "Unsupported TMDS char rate: %lld\n", rate);
		return MODE_CLOCK_HIGH;
	}

	return MODE_OK;
}

static int dw_hdmi_qp_bridge_clear_infoframe(struct drm_bridge *bridge,
					     enum hdmi_infoframe_type type)
{
	struct dw_hdmi_qp *hdmi = bridge->driver_private;

	switch (type) {
	case HDMI_INFOFRAME_TYPE_AVI:
		dw_hdmi_qp_mod(hdmi, 0, PKTSCHED_AVI_TX_EN | PKTSCHED_GCP_TX_EN,
			       PKTSCHED_PKT_EN);
		break;

	case HDMI_INFOFRAME_TYPE_DRM:
		dw_hdmi_qp_mod(hdmi, 0, PKTSCHED_DRMI_TX_EN, PKTSCHED_PKT_EN);
		break;

	case HDMI_INFOFRAME_TYPE_AUDIO:
		dw_hdmi_qp_mod(hdmi, 0,
			       PKTSCHED_ACR_TX_EN |
			       PKTSCHED_AUDS_TX_EN |
			       PKTSCHED_AUDI_TX_EN,
			       PKTSCHED_PKT_EN);
		break;
	default:
		dev_dbg(hdmi->dev, "Unsupported infoframe type %x\n", type);
	}

	return 0;
}

static int dw_hdmi_qp_bridge_write_infoframe(struct drm_bridge *bridge,
					     enum hdmi_infoframe_type type,
					     const u8 *buffer, size_t len)
{
	struct dw_hdmi_qp *hdmi = bridge->driver_private;

	dw_hdmi_qp_bridge_clear_infoframe(bridge, type);

	switch (type) {
	case HDMI_INFOFRAME_TYPE_AVI:
		return dw_hdmi_qp_config_avi_infoframe(hdmi, buffer, len);

	case HDMI_INFOFRAME_TYPE_DRM:
		return dw_hdmi_qp_config_drm_infoframe(hdmi, buffer, len);

	case HDMI_INFOFRAME_TYPE_AUDIO:
		return dw_hdmi_qp_config_audio_infoframe(hdmi, buffer, len);

	default:
		dev_dbg(hdmi->dev, "Unsupported infoframe type %x\n", type);
		return 0;
	}
}

static const struct drm_bridge_funcs dw_hdmi_qp_bridge_funcs = {
	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
	.atomic_reset = drm_atomic_helper_bridge_reset,
	.atomic_enable = dw_hdmi_qp_bridge_atomic_enable,
	.atomic_disable = dw_hdmi_qp_bridge_atomic_disable,
	.detect = dw_hdmi_qp_bridge_detect,
	.edid_read = dw_hdmi_qp_bridge_edid_read,
	.hdmi_tmds_char_rate_valid = dw_hdmi_qp_bridge_tmds_char_rate_valid,
	.hdmi_clear_infoframe = dw_hdmi_qp_bridge_clear_infoframe,
	.hdmi_write_infoframe = dw_hdmi_qp_bridge_write_infoframe,
	.hdmi_audio_startup = dw_hdmi_qp_audio_enable,
	.hdmi_audio_shutdown = dw_hdmi_qp_audio_disable,
	.hdmi_audio_prepare = dw_hdmi_qp_audio_prepare,
};

static irqreturn_t dw_hdmi_qp_main_hardirq(int irq, void *dev_id)
{
	struct dw_hdmi_qp *hdmi = dev_id;
	struct dw_hdmi_qp_i2c *i2c = hdmi->i2c;
	u32 stat;

	stat = dw_hdmi_qp_read(hdmi, MAINUNIT_1_INT_STATUS);

	i2c->stat = stat & (I2CM_OP_DONE_IRQ | I2CM_READ_REQUEST_IRQ |
			    I2CM_NACK_RCVD_IRQ);

	if (i2c->stat) {
		dw_hdmi_qp_write(hdmi, i2c->stat, MAINUNIT_1_INT_CLEAR);
		complete(&i2c->cmp);
	}

	if (stat)
		return IRQ_HANDLED;

	return IRQ_NONE;
}

static const struct regmap_config dw_hdmi_qp_regmap_config = {
	.reg_bits	= 32,
	.val_bits	= 32,
	.reg_stride	= 4,
	.max_register	= EARCRX_1_INT_FORCE,
};

static void dw_hdmi_qp_init_hw(struct dw_hdmi_qp *hdmi)
{
	dw_hdmi_qp_write(hdmi, 0, MAINUNIT_0_INT_MASK_N);
	dw_hdmi_qp_write(hdmi, 0, MAINUNIT_1_INT_MASK_N);
	dw_hdmi_qp_write(hdmi, 428571429, TIMER_BASE_CONFIG0);

	/* Software reset */
	dw_hdmi_qp_write(hdmi, 0x01, I2CM_CONTROL0);

	dw_hdmi_qp_write(hdmi, 0x085c085c, I2CM_FM_SCL_CONFIG0);

	dw_hdmi_qp_mod(hdmi, 0, I2CM_FM_EN, I2CM_INTERFACE_CONTROL0);

	/* Clear DONE and ERROR interrupts */
	dw_hdmi_qp_write(hdmi, I2CM_OP_DONE_CLEAR | I2CM_NACK_RCVD_CLEAR,
			 MAINUNIT_1_INT_CLEAR);

	if (hdmi->phy.ops->setup_hpd)
		hdmi->phy.ops->setup_hpd(hdmi, hdmi->phy.data);
}

struct dw_hdmi_qp *dw_hdmi_qp_bind(struct platform_device *pdev,
				   struct drm_encoder *encoder,
				   const struct dw_hdmi_qp_plat_data *plat_data)
{
	struct device *dev = &pdev->dev;
	struct dw_hdmi_qp *hdmi;
	void __iomem *regs;
	int ret;

	if (!plat_data->phy_ops || !plat_data->phy_ops->init ||
	    !plat_data->phy_ops->disable || !plat_data->phy_ops->read_hpd) {
		dev_err(dev, "Missing platform PHY ops\n");
		return ERR_PTR(-ENODEV);
	}

	hdmi = devm_drm_bridge_alloc(dev, struct dw_hdmi_qp, bridge,
				     &dw_hdmi_qp_bridge_funcs);
	if (IS_ERR(hdmi))
		return ERR_CAST(hdmi);

	hdmi->dev = dev;

	regs = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(regs))
		return ERR_CAST(regs);

	hdmi->regm = devm_regmap_init_mmio(dev, regs, &dw_hdmi_qp_regmap_config);
	if (IS_ERR(hdmi->regm)) {
		dev_err(dev, "Failed to configure regmap\n");
		return ERR_CAST(hdmi->regm);
	}

	hdmi->phy.ops = plat_data->phy_ops;
	hdmi->phy.data = plat_data->phy_data;

	dw_hdmi_qp_init_hw(hdmi);

	ret = devm_request_threaded_irq(dev, plat_data->main_irq,
					dw_hdmi_qp_main_hardirq, NULL,
					IRQF_SHARED, dev_name(dev), hdmi);
	if (ret)
		return ERR_PTR(ret);

	hdmi->bridge.driver_private = hdmi;
	hdmi->bridge.ops = DRM_BRIDGE_OP_DETECT |
			   DRM_BRIDGE_OP_EDID |
			   DRM_BRIDGE_OP_HDMI |
			   DRM_BRIDGE_OP_HDMI_AUDIO |
			   DRM_BRIDGE_OP_HPD;
	hdmi->bridge.of_node = pdev->dev.of_node;
	hdmi->bridge.type = DRM_MODE_CONNECTOR_HDMIA;
	hdmi->bridge.vendor = "Synopsys";
	hdmi->bridge.product = "DW HDMI QP TX";

	hdmi->bridge.ddc = dw_hdmi_qp_i2c_adapter(hdmi);
	if (IS_ERR(hdmi->bridge.ddc))
		return ERR_CAST(hdmi->bridge.ddc);

	hdmi->bridge.hdmi_audio_max_i2s_playback_channels = 8;
	hdmi->bridge.hdmi_audio_dev = dev;
	hdmi->bridge.hdmi_audio_dai_port = 1;

	ret = devm_drm_bridge_add(dev, &hdmi->bridge);
	if (ret)
		return ERR_PTR(ret);

	ret = drm_bridge_attach(encoder, &hdmi->bridge, NULL,
				DRM_BRIDGE_ATTACH_NO_CONNECTOR);
	if (ret)
		return ERR_PTR(ret);

	return hdmi;
}
EXPORT_SYMBOL_GPL(dw_hdmi_qp_bind);

void dw_hdmi_qp_resume(struct device *dev, struct dw_hdmi_qp *hdmi)
{
	dw_hdmi_qp_init_hw(hdmi);
}
EXPORT_SYMBOL_GPL(dw_hdmi_qp_resume);

MODULE_AUTHOR("Algea Cao <[email protected]>");
MODULE_AUTHOR("Cristian Ciocaltea <[email protected]>");
MODULE_DESCRIPTION("DW HDMI QP transmitter library");
MODULE_LICENSE("GPL");