path: root/drivers/gpu/drm/vc4/vc4_hdmi.c

/*
 * Copyright (C) 2015 Broadcom
 * Copyright (c) 2014 The Linux Foundation. All rights reserved.
 * Copyright (C) 2013 Red Hat
 * Author: Rob Clark <robdclark@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * DOC: VC4 Falcon HDMI module
 *
 * The HDMI core has a state machine and a PHY.  On BCM2835, most of
 * the unit operates off of the HSM clock from CPRMAN.  It also
 * internally uses the PLLH_PIX clock for the PHY.
 *
 * HDMI infoframes are kept within a small packet ram, where each
 * packet can be individually enabled for including in a frame.
 *
 * HDMI audio is implemented entirely within the HDMI IP block.  A
 * register in the HDMI encoder takes SPDIF frames from the DMA engine
 * and transfers them over an internal MAI (multi-channel audio
 * interconnect) bus to the encoder side for insertion into the video
 * blank regions.
 *
 * The driver's HDMI encoder does not yet support power management.
 * The HDMI encoder's power domain and the HSM/pixel clocks are kept
 * continuously running, and only the HDMI logic and packet ram are
 * powered off/on at disable/enable time.
 *
 * The driver does not yet support CEC control, though the HDMI
 * encoder block has CEC support.
 */

#include <drm/drm_atomic_helper.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_edid.h>
#include <linux/clk.h>
#include <linux/component.h>
#include <linux/i2c.h>
#include <linux/of_address.h>
#include <linux/of_gpio.h>
#include <linux/of_platform.h>
#include <linux/pm_runtime.h>
#include <linux/rational.h>
#include <sound/dmaengine_pcm.h>
#include <sound/pcm_drm_eld.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include "media/cec.h"
#include "vc4_drv.h"
#include "vc4_regs.h"

#define HSM_CLOCK_FREQ 163682864
#define CEC_CLOCK_FREQ 40000
#define CEC_CLOCK_DIV  (HSM_CLOCK_FREQ / CEC_CLOCK_FREQ)

/* HDMI audio information */
struct vc4_hdmi_audio {
	struct snd_soc_card card;
	struct snd_soc_dai_link link;
	int samplerate;
	int channels;
	struct snd_dmaengine_dai_dma_data dma_data;
	struct snd_pcm_substream *substream;
};

/* General HDMI hardware state. */
struct vc4_hdmi {
	struct platform_device *pdev;

	struct drm_encoder *encoder;
	struct drm_connector *connector;

	struct vc4_hdmi_audio audio;

	struct i2c_adapter *ddc;
	void __iomem *hdmicore_regs;
	void __iomem *hd_regs;
	int hpd_gpio;
	bool hpd_active_low;

	struct cec_adapter *cec_adap;
	struct cec_msg cec_rx_msg;
	bool cec_tx_ok;
	bool cec_irq_was_rx;

	struct clk *pixel_clock;
	struct clk *hsm_clock;
};

#define HDMI_READ(offset) readl(vc4->hdmi->hdmicore_regs + offset)
#define HDMI_WRITE(offset, val) writel(val, vc4->hdmi->hdmicore_regs + offset)
#define HD_READ(offset) readl(vc4->hdmi->hd_regs + offset)
#define HD_WRITE(offset, val) writel(val, vc4->hdmi->hd_regs + offset)

/* VC4 HDMI encoder KMS struct */
struct vc4_hdmi_encoder {
	struct vc4_encoder base;
	bool hdmi_monitor;
	bool limited_rgb_range;
	bool rgb_range_selectable;
};

static inline struct vc4_hdmi_encoder *
to_vc4_hdmi_encoder(struct drm_encoder *encoder)
{
	return container_of(encoder, struct vc4_hdmi_encoder, base.base);
}

/* VC4 HDMI connector KMS struct */
struct vc4_hdmi_connector {
	struct drm_connector base;

	/* Since the connector is attached to just the one encoder,
	 * this is the reference to it so we can do the best_encoder()
	 * hook.
	 */
	struct drm_encoder *encoder;
};

static inline struct vc4_hdmi_connector *
to_vc4_hdmi_connector(struct drm_connector *connector)
{
	return container_of(connector, struct vc4_hdmi_connector, base);
}

#define HDMI_REG(reg) { reg, #reg }
static const struct {
	u32 reg;
	const char *name;
} hdmi_regs[] = {
	HDMI_REG(VC4_HDMI_CORE_REV),
	HDMI_REG(VC4_HDMI_SW_RESET_CONTROL),
	HDMI_REG(VC4_HDMI_HOTPLUG_INT),
	HDMI_REG(VC4_HDMI_HOTPLUG),
	HDMI_REG(VC4_HDMI_MAI_CHANNEL_MAP),
	HDMI_REG(VC4_HDMI_MAI_CONFIG),
	HDMI_REG(VC4_HDMI_MAI_FORMAT),
	HDMI_REG(VC4_HDMI_AUDIO_PACKET_CONFIG),
	HDMI_REG(VC4_HDMI_RAM_PACKET_CONFIG),
	HDMI_REG(VC4_HDMI_HORZA),
	HDMI_REG(VC4_HDMI_HORZB),
	HDMI_REG(VC4_HDMI_FIFO_CTL),
	HDMI_REG(VC4_HDMI_SCHEDULER_CONTROL),
	HDMI_REG(VC4_HDMI_VERTA0),
	HDMI_REG(VC4_HDMI_VERTA1),
	HDMI_REG(VC4_HDMI_VERTB0),
	HDMI_REG(VC4_HDMI_VERTB1),
	HDMI_REG(VC4_HDMI_TX_PHY_RESET_CTL),
	HDMI_REG(VC4_HDMI_TX_PHY_CTL0),

	HDMI_REG(VC4_HDMI_CEC_CNTRL_1),
	HDMI_REG(VC4_HDMI_CEC_CNTRL_2),
	HDMI_REG(VC4_HDMI_CEC_CNTRL_3),
	HDMI_REG(VC4_HDMI_CEC_CNTRL_4),
	HDMI_REG(VC4_HDMI_CEC_CNTRL_5),
	HDMI_REG(VC4_HDMI_CPU_STATUS),
	HDMI_REG(VC4_HDMI_CPU_MASK_STATUS),

	HDMI_REG(VC4_HDMI_CEC_RX_DATA_1),
	HDMI_REG(VC4_HDMI_CEC_RX_DATA_2),
	HDMI_REG(VC4_HDMI_CEC_RX_DATA_3),
	HDMI_REG(VC4_HDMI_CEC_RX_DATA_4),
	HDMI_REG(VC4_HDMI_CEC_TX_DATA_1),
	HDMI_REG(VC4_HDMI_CEC_TX_DATA_2),
	HDMI_REG(VC4_HDMI_CEC_TX_DATA_3),
	HDMI_REG(VC4_HDMI_CEC_TX_DATA_4),
};

static const struct {
	u32 reg;
	const char *name;
} hd_regs[] = {
	HDMI_REG(VC4_HD_M_CTL),
	HDMI_REG(VC4_HD_MAI_CTL),
	HDMI_REG(VC4_HD_MAI_THR),
	HDMI_REG(VC4_HD_MAI_FMT),
	HDMI_REG(VC4_HD_MAI_SMP),
	HDMI_REG(VC4_HD_VID_CTL),
	HDMI_REG(VC4_HD_CSC_CTL),
	HDMI_REG(VC4_HD_FRAME_COUNT),
};

#ifdef CONFIG_DEBUG_FS
int vc4_hdmi_debugfs_regs(struct seq_file *m, void *unused)
{
	struct drm_info_node *node = (struct drm_info_node *)m->private;
	struct drm_device *dev = node->minor->dev;
	struct vc4_dev *vc4 = to_vc4_dev(dev);
	int i;

	for (i = 0; i < ARRAY_SIZE(hdmi_regs); i++) {
		seq_printf(m, "%s (0x%04x): 0x%08x\n",
			   hdmi_regs[i].name, hdmi_regs[i].reg,
			   HDMI_READ(hdmi_regs[i].reg));
	}

	for (i = 0; i < ARRAY_SIZE(hd_regs); i++) {
		seq_printf(m, "%s (0x%04x): 0x%08x\n",
			   hd_regs[i].name, hd_regs[i].reg,
			   HD_READ(hd_regs[i].reg));
	}

	return 0;
}
#endif /* CONFIG_DEBUG_FS */

static void vc4_hdmi_dump_regs(struct drm_device *dev)
{
	struct vc4_dev *vc4 = to_vc4_dev(dev);
	int i;

	for (i = 0; i < ARRAY_SIZE(hdmi_regs); i++) {
		DRM_INFO("0x%04x (%s): 0x%08x\n",
			 hdmi_regs[i].reg, hdmi_regs[i].name,
			 HDMI_READ(hdmi_regs[i].reg));
	}
	for (i = 0; i < ARRAY_SIZE(hd_regs); i++) {
		DRM_INFO("0x%04x (%s): 0x%08x\n",
			 hd_regs[i].reg, hd_regs[i].name,
			 HD_READ(hd_regs[i].reg));
	}
}

static enum drm_connector_status
vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
{
	struct drm_device *dev = connector->dev;
	struct vc4_dev *vc4 = to_vc4_dev(dev);

	if (vc4->hdmi->hpd_gpio) {
		if (gpio_get_value_cansleep(vc4->hdmi->hpd_gpio) ^
		    vc4->hdmi->hpd_active_low)
			return connector_status_connected;
		cec_phys_addr_invalidate(vc4->hdmi->cec_adap);
		return connector_status_disconnected;
	}

	if (drm_probe_ddc(vc4->hdmi->ddc))
		return connector_status_connected;

	if (HDMI_READ(VC4_HDMI_HOTPLUG) & VC4_HDMI_HOTPLUG_CONNECTED)
		return connector_status_connected;
	cec_phys_addr_invalidate(vc4->hdmi->cec_adap);
	return connector_status_disconnected;
}

static void vc4_hdmi_connector_destroy(struct drm_connector *connector)
{
	drm_connector_unregister(connector);
	drm_connector_cleanup(connector);
}

static int vc4_hdmi_connector_get_modes(struct drm_connector *connector)
{
	struct vc4_hdmi_connector *vc4_connector =
		to_vc4_hdmi_connector(connector);
	struct drm_encoder *encoder = vc4_connector->encoder;
	struct vc4_hdmi_encoder *vc4_encoder = to_vc4_hdmi_encoder(encoder);
	struct drm_device *dev = connector->dev;
	struct vc4_dev *vc4 = to_vc4_dev(dev);
	int ret = 0;
	struct edid *edid;

	edid = drm_get_edid(connector, vc4->hdmi->ddc);
	cec_s_phys_addr_from_edid(vc4->hdmi->cec_adap