Re: [PATCH 4/4] drm/bridge: dw-hdmi: add cec driver

On 05/30/2017 04:23 PM, Russell King wrote:

Add a CEC driver for the dw-hdmi hardware.

Signed-off-by: Russell King rmk+kernel@armlinux.org.uk

drivers/gpu/drm/bridge/synopsys/Kconfig | 8 + drivers/gpu/drm/bridge/synopsys/Makefile | 1 + drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c | 320 ++++++++++++++++++++++++++ drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.h | 19 ++ drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 40 +++- 5 files changed, 387 insertions(+), 1 deletion(-) create mode 100644 drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c create mode 100644 drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.h

diff --git a/drivers/gpu/drm/bridge/synopsys/Kconfig b/drivers/gpu/drm/bridge/synopsys/Kconfig index 40d2827a6d19..bd30a0a07272 100644 --- a/drivers/gpu/drm/bridge/synopsys/Kconfig +++ b/drivers/gpu/drm/bridge/synopsys/Kconfig @@ -21,3 +21,11 @@ config DRM_DW_HDMI_I2S_AUDIO help Support the I2S Audio interface which is part of the Synopsys Designware HDMI block.

+config DRM_DW_HDMI_CEC

• tristate "Synopsis Designware CEC interface"
• depends on DRM_DW_HDMI && MEDIA_CEC_SUPPORT
• select MEDIA_CEC_NOTIFIER
• help

•  Support the CE interface which is part of the Synopsis
  

•  Designware HDMI block.
  

diff --git a/drivers/gpu/drm/bridge/synopsys/Makefile b/drivers/gpu/drm/bridge/synopsys/Makefile index 17aa7a65b57e..6fe415903668 100644 --- a/drivers/gpu/drm/bridge/synopsys/Makefile +++ b/drivers/gpu/drm/bridge/synopsys/Makefile @@ -3,3 +3,4 @@ obj-$(CONFIG_DRM_DW_HDMI) += dw-hdmi.o obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o obj-$(CONFIG_DRM_DW_HDMI_I2S_AUDIO) += dw-hdmi-i2s-audio.o +obj-$(CONFIG_DRM_DW_HDMI_CEC) += dw-hdmi-cec.o diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c new file mode 100644 index 000000000000..761ef5ae687d --- /dev/null +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.c @@ -0,0 +1,320 @@ +/*

• • Designware HDMI CEC driver
• • Copyright (C) 2015-2017 Russell King.
• • 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.
• */

+#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/sched.h> +#include <linux/slab.h>

+#include <drm/drm_edid.h>

+#include <media/cec.h> +#include <media/cec-notifier.h>

+#include "dw-hdmi-cec.h"

+enum {

• HDMI_IH_CEC_STAT0 = 0x0106,
• HDMI_IH_MUTE_CEC_STAT0 = 0x0186,
• HDMI_CEC_CTRL = 0x7d00,
• CEC_CTRL_START = BIT(0),
• CEC_CTRL_NORMAL = 1 << 1,
• HDMI_CEC_STAT = 0x7d01,
• CEC_STAT_DONE = BIT(0),
• CEC_STAT_EOM = BIT(1),
• CEC_STAT_NACK = BIT(2),
• CEC_STAT_ARBLOST = BIT(3),
• CEC_STAT_ERROR_INIT = BIT(4),
• CEC_STAT_ERROR_FOLL = BIT(5),
• CEC_STAT_WAKEUP = BIT(6),
• HDMI_CEC_MASK = 0x7d02,
• HDMI_CEC_POLARITY = 0x7d03,
• HDMI_CEC_INT = 0x7d04,
• HDMI_CEC_ADDR_L = 0x7d05,
• HDMI_CEC_ADDR_H = 0x7d06,
• HDMI_CEC_TX_CNT = 0x7d07,
• HDMI_CEC_RX_CNT = 0x7d08,
• HDMI_CEC_TX_DATA0 = 0x7d10,
• HDMI_CEC_RX_DATA0 = 0x7d20,
• HDMI_CEC_LOCK = 0x7d30,
• HDMI_CEC_WKUPCTRL = 0x7d31,

+};

+struct dw_hdmi_cec {

• struct dw_hdmi *hdmi;
• const struct dw_hdmi_cec_ops *ops;
• u32 addresses;
• struct cec_adapter *adap;
• struct cec_msg rx_msg;
• unsigned int tx_status;
• bool tx_done;
• bool rx_done;
• struct cec_notifier *notify;
• int retries;
• int irq;

+};

+static void dw_hdmi_write(struct dw_hdmi_cec *cec, u8 val, int offset) +{

• cec->ops->write(cec->hdmi, val, offset);

+}

+static u8 dw_hdmi_read(struct dw_hdmi_cec *cec, int offset) +{

• return cec->ops->read(cec->hdmi, offset);

+}

+static int dw_hdmi_cec_log_addr(struct cec_adapter *adap, u8 logical_addr) +{

• struct dw_hdmi_cec *cec = adap->priv;
• u32 addresses;
• if (logical_addr == CEC_LOG_ADDR_INVALID)

• addresses = cec->addresses = 0;
  

• else

• addresses = cec->addresses |= BIT(logical_addr) | BIT(15);
  

• dw_hdmi_write(cec, addresses & 255, HDMI_CEC_ADDR_L);
• dw_hdmi_write(cec, addresses >> 8, HDMI_CEC_ADDR_H);
• return 0;

+}

+static int dw_hdmi_cec_transmit(struct cec_adapter *adap, u8 attempts,

• 		u32 signal_free_time, struct cec_msg *msg)
  

+{

• struct dw_hdmi_cec *cec = adap->priv;
• unsigned i;
• cec->retries = attempts;
• for (i = 0; i < msg->len; i++)

• dw_hdmi_write(cec, msg->msg[i], HDMI_CEC_TX_DATA0 + i);
  

• dw_hdmi_write(cec, msg->len, HDMI_CEC_TX_CNT);
• dw_hdmi_write(cec, CEC_CTRL_NORMAL | CEC_CTRL_START, HDMI_CEC_CTRL);
• return 0;

+}

+static irqreturn_t dw_hdmi_cec_hardirq(int irq, void *data) +{

• struct cec_adapter *adap = data;
• struct dw_hdmi_cec *cec = adap->priv;
• unsigned stat = dw_hdmi_read(cec, HDMI_IH_CEC_STAT0);
• irqreturn_t ret = IRQ_HANDLED;
• if (stat == 0)

• return IRQ_NONE;
  

• dw_hdmi_write(cec, stat, HDMI_IH_CEC_STAT0);
• if (stat & CEC_STAT_ERROR_INIT) {

• if (cec->retries) {
  

• 	unsigned v = dw_hdmi_read(cec, HDMI_CEC_CTRL);
  

• 	dw_hdmi_write(cec, v | CEC_CTRL_START, HDMI_CEC_CTRL);
  

• 	cec->retries -= 1;
  

• } else {
  

• 	cec->tx_status = CEC_TX_STATUS_MAX_RETRIES;
  

• 	cec->tx_done = true;
  

• 	ret = IRQ_WAKE_THREAD;
  

• }
  

• } else if (stat & CEC_STAT_DONE) {

• cec->tx_status = CEC_TX_STATUS_OK;
  

• cec->tx_done = true;
  

• ret = IRQ_WAKE_THREAD;
  

• } else if (stat & CEC_STAT_NACK) {

• cec->tx_status = CEC_TX_STATUS_NACK;
  

• cec->tx_done = true;
  

• ret = IRQ_WAKE_THREAD;
  

• }
• if (stat & CEC_STAT_EOM) {

• unsigned len, i;
  

• len = dw_hdmi_read(cec, HDMI_CEC_RX_CNT);
  

• if (len > sizeof(cec->rx_msg.msg))
  

• 	len = sizeof(cec->rx_msg.msg);
  

• for (i = 0; i < len; i++)
  

• 	cec->rx_msg.msg[i] =
  

• 		dw_hdmi_read(cec, HDMI_CEC_RX_DATA0 + i);
  

• dw_hdmi_write(cec, 0, HDMI_CEC_LOCK);
  

• cec->rx_msg.len = len;
  

• smp_wmb();
  

• cec->rx_done = true;
  

• ret = IRQ_WAKE_THREAD;
  

• }
• return ret;

+}

+static irqreturn_t dw_hdmi_cec_thread(int irq, void *data) +{

• struct cec_adapter *adap = data;
• struct dw_hdmi_cec *cec = adap->priv;
• if (cec->tx_done) {

• cec->tx_done = false;
  

• cec_transmit_done(adap, cec->tx_status, 0, 0, 0, 0);
  

• }
• if (cec->rx_done) {

• cec->rx_done = false;
  

• smp_rmb();
  

• cec_received_msg(adap, &cec->rx_msg);
  

• }
• return IRQ_HANDLED;

+}

+static int dw_hdmi_cec_enable(struct cec_adapter *adap, bool enable) +{

• struct dw_hdmi_cec *cec = adap->priv;
• if (!enable) {

• dw_hdmi_write(cec, ~0, HDMI_CEC_MASK);
  

• dw_hdmi_write(cec, ~0, HDMI_IH_MUTE_CEC_STAT0);
  

• dw_hdmi_write(cec, 0, HDMI_CEC_POLARITY);
  

• cec->ops->disable(cec->hdmi);
  

• } else {

• unsigned irqs;
  

• dw_hdmi_write(cec, 0, HDMI_CEC_CTRL);
  

• dw_hdmi_write(cec, ~0, HDMI_IH_CEC_STAT0);
  

• dw_hdmi_write(cec, 0, HDMI_CEC_LOCK);
  

• dw_hdmi_cec_log_addr(cec->adap, CEC_LOG_ADDR_INVALID);
  

• cec->ops->enable(cec->hdmi);
  

• irqs = CEC_STAT_ERROR_INIT | CEC_STAT_NACK | CEC_STAT_EOM |
  

•        CEC_STAT_DONE;
  

• dw_hdmi_write(cec, irqs, HDMI_CEC_POLARITY);
  

• dw_hdmi_write(cec, ~irqs, HDMI_CEC_MASK);
  

• dw_hdmi_write(cec, ~irqs, HDMI_IH_MUTE_CEC_STAT0);
  

• }
• return 0;

+}

+static const struct cec_adap_ops dw_hdmi_cec_ops = {

• .adap_enable = dw_hdmi_cec_enable,
• .adap_log_addr = dw_hdmi_cec_log_addr,
• .adap_transmit = dw_hdmi_cec_transmit,

+};

+static void dw_hdmi_cec_del(void *data) +{

• struct dw_hdmi_cec *cec = data;
• cec_delete_adapter(cec->adap);

+}

+static int dw_hdmi_cec_probe(struct platform_device *pdev) +{

• struct dw_hdmi_cec_data *data = dev_get_platdata(&pdev->dev);
• struct dw_hdmi_cec *cec;
• int ret;
• if (!data)

• return -ENXIO;
  

• /*

• * Our device is just a convenience - we want to link to the real
  

• * hardware device here, so that userspace can see the association
  

• * between the HDMI hardware and its associated CEC chardev.
  

• */
  

• cec = devm_kzalloc(&pdev->dev, sizeof(*cec), GFP_KERNEL);
• if (!cec)

• return -ENOMEM;
  

• cec->irq = data->irq;
• cec->ops = data->ops;
• cec->hdmi = data->hdmi;
• platform_set_drvdata(pdev, cec);
• dw_hdmi_write(cec, 0, HDMI_CEC_TX_CNT);
• dw_hdmi_write(cec, ~0, HDMI_CEC_MASK);
• dw_hdmi_write(cec, ~0, HDMI_IH_MUTE_CEC_STAT0);
• dw_hdmi_write(cec, 0, HDMI_CEC_POLARITY);
• cec->adap = cec_allocate_adapter(&dw_hdmi_cec_ops, cec, "dw_hdmi",

• 			 CEC_CAP_LOG_ADDRS | CEC_CAP_TRANSMIT |
  

• 			 CEC_CAP_RC, CEC_MAX_LOG_ADDRS);
  

• if (IS_ERR(cec->adap))

• return PTR_ERR(cec->adap);
  

• /* override the module pointer */
• cec->adap->owner = THIS_MODULE;
• ret = devm_add_action(&pdev->dev, dw_hdmi_cec_del, cec);
• if (ret) {

• cec_delete_adapter(cec->adap);
  

• return ret;
  

• }
• ret = devm_request_threaded_irq(&pdev->dev, cec->irq,

• 			dw_hdmi_cec_hardirq,
  

• 			dw_hdmi_cec_thread, IRQF_SHARED,
  

• 			"dw-hdmi-cec", cec->adap);
  

• if (ret < 0)

• return ret;
  

• cec->notify = cec_notifier_get(pdev->dev.parent);
• if (!cec->notify)

• return -ENOMEM;
  

• ret = cec_register_adapter(cec->adap, pdev->dev.parent);
• if (ret < 0) {

• cec_notifier_put(cec->notify);
  

• return ret;
  

• }
• /*

• * CEC documentation says we must not call cec_delete_adapter
  

• * after a successful call to cec_register_adapter().
  

• */
  

• devm_remove_action(&pdev->dev, dw_hdmi_cec_del, cec);
• cec_register_cec_notifier(cec->adap, cec->notify);
• return 0;

+}

+static int dw_hdmi_cec_remove(struct platform_device *pdev) +{

• struct dw_hdmi_cec *cec = platform_get_drvdata(pdev);
• cec_unregister_adapter(cec->adap);
• cec_notifier_put(cec->notify);
• return 0;

+}

+static struct platform_driver dw_hdmi_cec_driver = {

• .probe = dw_hdmi_cec_probe,
• .remove = dw_hdmi_cec_remove,
• .driver = {

• .name = "dw-hdmi-cec",
  

• },

+}; +module_platform_driver(dw_hdmi_cec_driver);

+MODULE_AUTHOR("Russell King rmk+kernel@armlinux.org.uk"); +MODULE_DESCRIPTION("Synopsis Designware HDMI CEC driver for i.MX"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS(PLATFORM_MODULE_PREFIX "dw-hdmi-cec"); diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.h b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.h new file mode 100644 index 000000000000..cf4dc121a2c4 --- /dev/null +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-cec.h @@ -0,0 +1,19 @@ +#ifndef DW_HDMI_CEC_H +#define DW_HDMI_CEC_H

+struct dw_hdmi;

+struct dw_hdmi_cec_ops {

• void (*write)(struct dw_hdmi *hdmi, u8 val, int offset);
• u8 (*read)(struct dw_hdmi *hdmi, int offset);
• void (*enable)(struct dw_hdmi *hdmi);
• void (*disable)(struct dw_hdmi *hdmi);

+};

+struct dw_hdmi_cec_data {

• struct dw_hdmi *hdmi;
• const struct dw_hdmi_cec_ops *ops;
• int irq;

+};

+#endif diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c index 58781d4c1034..5a389f1f58d9 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c @@ -35,6 +35,7 @@

#include "dw-hdmi.h" #include "dw-hdmi-audio.h" +#include "dw-hdmi-cec.h"

#include <media/cec-notifier.h>

@@ -133,6 +134,7 @@ struct dw_hdmi { unsigned int version;

struct platform_device *audio;

• struct platform_device *cec; struct device *dev; struct clk *isfr_clk; struct clk *iahb_clk;

@@ -1766,7 +1768,6 @@ static void initialize_hdmi_ih_mutes(struct dw_hdmi *hdmi) hdmi_writeb(hdmi, 0xff, HDMI_AUD_HBR_MASK); hdmi_writeb(hdmi, 0xff, HDMI_GP_MASK); hdmi_writeb(hdmi, 0xff, HDMI_A_APIINTMSK);

• hdmi_writeb(hdmi, 0xff, HDMI_CEC_MASK); hdmi_writeb(hdmi, 0xff, HDMI_I2CM_INT); hdmi_writeb(hdmi, 0xff, HDMI_I2CM_CTLINT);

@@ -2223,6 +2224,29 @@ static int dw_hdmi_detect_phy(struct dw_hdmi *hdmi) return -ENODEV; }

+static void dw_hdmi_cec_enable(struct dw_hdmi *hdmi) +{

• mutex_lock(&hdmi->mutex);
• hdmi->mc_clkdis &= ~HDMI_MC_CLKDIS_CECCLK_DISABLE;
• hdmi_writeb(hdmi, hdmi->mc_clkdis, HDMI_MC_CLKDIS);
• mutex_unlock(&hdmi->mutex);

+}

+static void dw_hdmi_cec_disable(struct dw_hdmi *hdmi) +{

• mutex_lock(&hdmi->mutex);
• hdmi->mc_clkdis |= HDMI_MC_CLKDIS_CECCLK_DISABLE;
• hdmi_writeb(hdmi, hdmi->mc_clkdis, HDMI_MC_CLKDIS);
• mutex_unlock(&hdmi->mutex);

+}

+static const struct dw_hdmi_cec_ops dw_hdmi_cec_ops = {

• .write = hdmi_writeb,
• .read = hdmi_readb,
• .enable = dw_hdmi_cec_enable,
• .disable = dw_hdmi_cec_disable,

+};

static const struct regmap_config hdmi_regmap_8bit_config = { .reg_bits = 32, .val_bits = 8, @@ -2245,6 +2269,7 @@ __dw_hdmi_probe(struct platform_device *pdev, struct device_node *np = dev->of_node; struct platform_device_info pdevinfo; struct device_node *ddc_node;

• struct dw_hdmi_cec_data cec; struct dw_hdmi *hdmi; struct resource *iores = NULL; int irq;

@@ -2445,6 +2470,17 @@ __dw_hdmi_probe(struct platform_device *pdev, hdmi->audio = platform_device_register_full(&pdevinfo); }

• cec.hdmi = hdmi;
• cec.ops = &dw_hdmi_cec_ops;
• cec.irq = irq;
• pdevinfo.name = "dw-hdmi-cec";
• pdevinfo.data = &cec;
• pdevinfo.size_data = sizeof(cec);
• pdevinfo.dma_mask = 0;
• hdmi->cec = platform_device_register_full(&pdevinfo);

Maybe you should check the config bit before enabling CEC :

/* CONFIG0_ID field values */ + HDMI_CONFIG0_CEC = 0x2,

if (config0 & HDMI_CONFIG0_CEC) { }

• /* Reset HDMI DDC I2C master controller and mute I2CM interrupts */ if (hdmi->i2c) dw_hdmi_i2c_init(hdmi);

@@ -2475,6 +2511,8 @@ static void __dw_hdmi_remove(struct dw_hdmi *hdmi) { if (hdmi->audio && !IS_ERR(hdmi->audio)) platform_device_unregister(hdmi->audio);

• if (!IS_ERR(hdmi->cec))

• platform_device_unregister(hdmi->cec);
  
  

  /* Disable all interrupts */ hdmi_writeb(hdmi, ~0, HDMI_IH_MUTE_PHY_STAT0);

Apart from that and the s/Synopsis/Synopsys/ typos:

Reviewed-by: Neil Armstrong narmstrong@baylibre.com

Neil