[RFC v2 2/2] drm/bridge: Add I2C based driver for ps8640 bridge

jitao shi jitao.shi at mediatek.com
Sun Nov 1 19:54:56 PST 2015


On Mon, 2015-11-02 at 10:09 +0800, Jitao Shi wrote:
> This patch adds drm_bridge driver for parade DSI to eDP bridge chip.
> 
> Signed-off-by: Jitao Shi <jitao.shi at mediatek.com>
---
changes since v1:
        1. remove edid code
        2. remove some wrong comments
        3. tune some gpios name, make it easy understand the meaning
> ---
>  drivers/gpu/drm/bridge/Kconfig         |    9 +
>  drivers/gpu/drm/bridge/Makefile        |    1 +
>  drivers/gpu/drm/bridge/parade-ps8640.c |  479 ++++++++++++++++++++++++++++++++
>  3 files changed, 489 insertions(+)
>  create mode 100644 drivers/gpu/drm/bridge/parade-ps8640.c
> 
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index 2de52a5..8ecaeed 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -29,4 +29,13 @@ config DRM_PARADE_PS8622
>  	---help---
>  	  Parade eDP-LVDS bridge chip driver.
>  
> +config DRM_PARADE_PS8640
> +	bool "Parade PS8640 MIPI DSI to eDP Converter"
> +	select DRM_KMS_HELPER
> +	select DRM_PANEL
> +	---help---
> +	  Choose this option if you have PS8640 for display
> +	  The PS8640 is a high-performance and low-power
> +	  MIPI DSI to eDP converter
> +
>  endmenu
> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> index e2eef1c..da9e4a4 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -3,3 +3,4 @@ ccflags-y := -Iinclude/drm
>  obj-$(CONFIG_DRM_DW_HDMI) += dw_hdmi.o
>  obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
>  obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
> +obj-$(CONFIG_DRM_PARADE_PS8640) += parade-ps8640.o
> diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
> new file mode 100644
> index 0000000..52616ba
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/parade-ps8640.c
> @@ -0,0 +1,479 @@
> +/*
> + * Copyright (c) 2014 MediaTek Inc.
> + *
> + * 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.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_gpio.h>
> +#include <linux/i2c.h>
> +#include <linux/gpio.h>
> +#include <linux/delay.h>
> +#include <linux/of_graph.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include <drm/drmP.h>
> +#include <drm/drm_crtc_helper.h>
> +#include <drm/drm_crtc.h>
> +#include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_panel.h>
> +#include <drm/drm_atomic_helper.h>
> +
> +#define PAGE2_GPIO_L	0xa6
> +#define PAGE2_GPIO_H	0xa7
> +#define PS_GPIO9	BIT(1)
> +
> +#define PAGE4_REV_L	0xf0
> +#define PAGE4_REV_H	0xf1
> +#define PAGE4_CHIP_L	0xf2
> +#define PAGE4_CHIP_H	0xf3
> +
> +#define bridge_to_ps8640(e)	container_of(e, struct ps8640, bridge)
> +#define connector_to_ps8640(e)	container_of(e, struct ps8640, connector)
> +
> +struct ps8640 {
> +	struct drm_connector connector;
> +	struct drm_bridge bridge;
> +	struct i2c_client *client;
> +	struct ps8640_driver_data *driver_data;
> +	struct regulator *pwr_1v2_supply;
> +	struct regulator *pwr_3v3_supply;
> +	struct drm_panel *panel;
> +	struct gpio_desc *gpio_rst_n;
> +	struct gpio_desc *gpio_slp_n;
> +	struct gpio_desc *gpio_mode_sel_n;
> +	u16 base_reg;
> +	bool enabled;
> +};
> +
> +static int ps8640_regr(struct i2c_client *client, u16 i2c_addr,
> +		       u8 reg, u8 *value)
> +{
> +	int ret;
> +
> +	client->addr = i2c_addr;
> +
> +	ret = i2c_master_send(client, &reg, 1);
> +	if (ret <= 0) {
> +		DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = i2c_master_recv(client, value, 1);
> +	if (ret <= 0) {
> +		DRM_ERROR("Failed to recv i2c data, ret=%d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int ps8640_regw(struct i2c_client *client, u16 i2c_addr,
> +		       u8 reg, u8 value)
> +{
> +	int ret;
> +	char buf[2];
> +
> +	client->addr = i2c_addr;
> +
> +	buf[0] = reg;
> +	buf[1] = value;
> +	ret = i2c_master_send(client, buf, ARRAY_SIZE(buf));
> +	if (ret <= 0) {
> +		DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int ps8640_check_valid_id(struct ps8640 *ps_bridge)
> +{
> +	struct i2c_client *client = ps_bridge->client;
> +	u8 rev_id_low, rev_id_high, chip_id_low, chip_id_high;
> +	int retry_cnt = 0;
> +
> +	do {
> +		ps8640_regr(client, ps_bridge->base_reg + 4, PAGE4_CHIP_H,
> +			    &chip_id_high);
> +		if (chip_id_high != 0x30)
> +			DRM_INFO("chip_id_high = 0x%x\n", chip_id_high);
> +	} while ((retry_cnt++ < 2) && (chip_id_high != 0x30));
> +
> +	ps8640_regr(client, ps_bridge->base_reg + 4, PAGE4_REV_L, &rev_id_low);
> +	ps8640_regr(client, ps_bridge->base_reg + 4, PAGE4_REV_H, &rev_id_high);
> +	ps8640_regr(client, ps_bridge->base_reg + 4, PAGE4_CHIP_L,
> +		    &chip_id_low);
> +
> +	if ((rev_id_low == 0x00) && (rev_id_high == 0x0a) &&
> +	    (chip_id_low == 0x00) && (chip_id_high == 0x30))
> +		return 1;
> +
> +	return 0;
> +}
> +
> +static void ps8640_show_mcu_fw_version(struct ps8640 *ps_bridge)
> +{
> +	struct i2c_client *client = ps_bridge->client;
> +	u8 major_ver, minor_ver;
> +
> +	ps8640_regr(client, ps_bridge->base_reg + 5, 0x4, &major_ver);
> +	ps8640_regr(client, ps_bridge->base_reg + 5, 0x5, &minor_ver);
> +
> +	DRM_INFO_ONCE("ps8640 rom fw version %d.%d\n", major_ver, minor_ver);
> +}
> +
> +static int ps8640_bdg_enable(struct ps8640 *ps_bridge)
> +{
> +	struct i2c_client *client = ps_bridge->client;
> +
> +	if (ps8640_check_valid_id(ps_bridge)) {
> +		ps8640_regw(client, ps_bridge->base_reg + 3, 0xfe, 0x13);
> +		ps8640_regw(client, ps_bridge->base_reg + 3, 0xff, 0x18);
> +		ps8640_regw(client, ps_bridge->base_reg + 3, 0xfe, 0x13);
> +		ps8640_regw(client, ps_bridge->base_reg + 3, 0xff, 0x1c);
> +
> +		return 0;
> +	}
> +
> +	return -1;
> +}
> +
> +static void ps8640_prepare(struct ps8640 *ps_bridge)
> +{
> +	struct i2c_client *client = ps_bridge->client;
> +	int err, retry_cnt = 0;
> +	u8 set_vdo_done;
> +
> +	if (ps_bridge->enabled)
> +		return;
> +
> +	if (drm_panel_prepare(ps_bridge->panel)) {
> +		DRM_ERROR("failed to prepare panel\n");
> +		return;
> +	}
> +
> +	err = regulator_enable(ps_bridge->pwr_1v2_supply);
> +	if (err < 0) {
> +		DRM_ERROR("failed to enable pwr_1v2_supply: %d\n", err);
> +		return;
> +	}
> +
> +	err = regulator_enable(ps_bridge->pwr_3v3_supply);
> +	if (err < 0) {
> +		DRM_ERROR("failed to enable pwr_3v3_supply: %d\n", err);
> +		return;
> +	}
> +
> +	gpiod_set_value(ps_bridge->gpio_slp_n, 1);
> +	gpiod_set_value(ps_bridge->gpio_rst_n, 0);
> +	usleep_range(500, 700);
> +	gpiod_set_value(ps_bridge->gpio_rst_n, 1);
> +
> +	do {
> +		msleep(50);
> +		ps8640_regr(client, ps_bridge->base_reg + 2, PAGE2_GPIO_H,
> +			    &set_vdo_done);
> +	} while ((retry_cnt++ < 70) && ((set_vdo_done & PS_GPIO9) != PS_GPIO9));
> +
> +	ps8640_show_mcu_fw_version(ps_bridge);
> +	ps_bridge->enabled = true;
> +}
> +
> +static void ps8640_pre_enable(struct drm_bridge *bridge)
> +{
> +	struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
> +
> +	ps8640_prepare(ps_bridge);
> +}
> +
> +static void ps8640_enable(struct drm_bridge *bridge)
> +{
> +	struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
> +
> +	ps8640_bdg_enable(ps_bridge);
> +
> +	if (drm_panel_enable(ps_bridge->panel)) {
> +		DRM_ERROR("failed to enable panel\n");
> +		return;
> +	}
> +}
> +
> +static void ps8640_disable(struct drm_bridge *bridge)
> +{
> +	struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
> +
> +	if (!ps_bridge->enabled)
> +		return;
> +
> +	ps_bridge->enabled = false;
> +
> +	if (drm_panel_disable(ps_bridge->panel)) {
> +		DRM_ERROR("failed to disable panel\n");
> +		return;
> +	}
> +
> +	regulator_disable(ps_bridge->pwr_1v2_supply);
> +	regulator_disable(ps_bridge->pwr_3v3_supply);
> +	gpiod_set_value(ps_bridge->gpio_rst_n, 0);
> +	gpiod_set_value(ps_bridge->gpio_slp_n, 0);
> +}
> +
> +static void ps8640_post_disable(struct drm_bridge *bridge)
> +{
> +	struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
> +
> +	if (drm_panel_unprepare(ps_bridge->panel)) {
> +		DRM_ERROR("failed to unprepare panel\n");
> +		return;
> +	}
> +}
> +
> +static int ps8640_get_modes(struct drm_connector *connector)
> +{
> +	struct ps8640 *ps_bridge = connector_to_ps8640(connector);
> +	struct i2c_client *client = ps_bridge->client;
> +
> +	ps8640_prepare(ps_bridge);
> +	ps8640_regw(client, ps_bridge->base_reg + 2, 0xea, 0xd0);
> +
> +	return drm_panel_get_modes(ps_bridge->panel);
> +}
> +
> +static struct drm_encoder *ps8640_best_encoder(struct drm_connector *connector)
> +{
> +	struct ps8640 *ps_bridge;
> +
> +	ps_bridge = connector_to_ps8640(connector);
> +	return ps_bridge->bridge.encoder;
> +}
> +
> +static const struct drm_connector_helper_funcs
> +	ps8640_connector_helper_funcs = {
> +	.get_modes = ps8640_get_modes,
> +	.best_encoder = ps8640_best_encoder,
> +};
> +
> +static enum drm_connector_status ps8640_detect(struct drm_connector *connector,
> +					       bool force)
> +{
> +	return connector_status_connected;
> +}
> +
> +static void ps8640_connector_destroy(struct drm_connector *connector)
> +{
> +	drm_connector_unregister(connector);
> +	drm_connector_cleanup(connector);
> +}
> +
> +static const struct drm_connector_funcs ps8640_connector_funcs = {
> +	.dpms = drm_atomic_helper_connector_dpms,
> +	.fill_modes = drm_helper_probe_single_connector_modes,
> +	.detect = ps8640_detect,
> +	.destroy = ps8640_connector_destroy,
> +	.reset = drm_atomic_helper_connector_reset,
> +	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> +	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> +};
> +
> +int ps8640_bridge_attach(struct drm_bridge *bridge)
> +{
> +	struct ps8640 *ps_bridge = bridge_to_ps8640(bridge);
> +	int ret;
> +
> +	if (!bridge->encoder) {
> +		DRM_ERROR("Parent encoder object not found");
> +		return -ENODEV;
> +	}
> +
> +	ret = drm_connector_init(bridge->dev, &ps_bridge->connector,
> +				 &ps8640_connector_funcs,
> +				 DRM_MODE_CONNECTOR_eDP);
> +
> +	if (ret) {
> +		DRM_ERROR("Failed to initialize connector with drm\n");
> +		return ret;
> +	}
> +
> +	drm_connector_helper_add(&ps_bridge->connector,
> +				 &ps8640_connector_helper_funcs);
> +	drm_connector_register(&ps_bridge->connector);
> +
> +	ps_bridge->connector.dpms = DRM_MODE_DPMS_ON;
> +	drm_mode_connector_attach_encoder(&ps_bridge->connector,
> +					  bridge->encoder);
> +
> +	if (ps_bridge->panel)
> +		drm_panel_attach(ps_bridge->panel, &ps_bridge->connector);
> +
> +	return ret;
> +}
> +
> +static bool ps8640_bridge_mode_fixup(struct drm_bridge *bridge,
> +				     const struct drm_display_mode *mode,
> +				     struct drm_display_mode *adjusted_mode)
> +{
> +	return true;
> +}
> +
> +static const struct drm_bridge_funcs ps8640_bridge_funcs = {
> +	.attach = ps8640_bridge_attach,
> +	.mode_fixup = ps8640_bridge_mode_fixup,
> +	.disable = ps8640_disable,
> +	.post_disable = ps8640_post_disable,
> +	.pre_enable = ps8640_pre_enable,
> +	.enable = ps8640_enable,
> +};
> +
> +static int ps8640_probe(struct i2c_client *client,
> +			const struct i2c_device_id *id)
> +{
> +	struct device *dev = &client->dev;
> +	struct ps8640 *ps_bridge;
> +	struct device_node *np = dev->of_node;
> +	struct device_node *in_ep, *out_ep;
> +	struct device_node *panel_node = NULL;
> +	int ret;
> +	u32 temp_reg;
> +
> +	ps_bridge = devm_kzalloc(dev, sizeof(*ps_bridge), GFP_KERNEL);
> +	if (!ps_bridge)
> +		return -ENOMEM;
> +
> +	in_ep = of_graph_get_next_endpoint(np, NULL);
> +	if (in_ep) {
> +		out_ep = of_graph_get_next_endpoint(np, in_ep);
> +		of_node_put(in_ep);
> +		if (out_ep) {
> +			panel_node = of_graph_get_remote_port_parent(out_ep);
> +			of_node_put(out_ep);
> +		}
> +	}
> +	if (panel_node) {
> +		ps_bridge->panel = of_drm_find_panel(panel_node);
> +		of_node_put(panel_node);
> +		if (!ps_bridge->panel)
> +			return -EPROBE_DEFER;
> +	}
> +
> +	ps_bridge->client = client;
> +
> +	ps_bridge->pwr_3v3_supply = devm_regulator_get(dev, "vdd33-supply");
> +	if (IS_ERR(ps_bridge->pwr_3v3_supply)) {
> +		dev_err(dev, "cannot get ps_bridge->pwr_3v3_supply\n");
> +		return PTR_ERR(ps_bridge->pwr_3v3_supply);
> +	}
> +
> +	ps_bridge->pwr_1v2_supply = devm_regulator_get(dev, "vdd12-supply");
> +	if (IS_ERR(ps_bridge->pwr_1v2_supply)) {
> +		dev_err(dev, "cannot get ps_bridge->pwr_1v2_supply\n");
> +		return PTR_ERR(ps_bridge->pwr_1v2_supply);
> +	}
> +
> +	ps_bridge->gpio_mode_sel_n = devm_gpiod_get(&client->dev, "mode-sel",
> +						    GPIOD_OUT_HIGH);
> +	if (IS_ERR(ps_bridge->gpio_mode_sel_n)) {
> +		ret = PTR_ERR(ps_bridge->gpio_mode_sel_n);
> +		DRM_ERROR("cannot get gpio_mode_sel_n %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = gpiod_direction_output(ps_bridge->gpio_mode_sel_n, 1);
> +	if (ret) {
> +		DRM_ERROR("cannot configure gpio_mode_sel_n\n");
> +		return ret;
> +	}
> +
> +	ps_bridge->gpio_slp_n = devm_gpiod_get(&client->dev, "sleep-gpios",
> +					       GPIOD_OUT_HIGH);
> +	if (IS_ERR(ps_bridge->gpio_slp_n)) {
> +		ret = PTR_ERR(ps_bridge->gpio_slp_n);
> +		DRM_ERROR("cannot get gpio_slp_n %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = gpiod_direction_output(ps_bridge->gpio_slp_n, 1);
> +	if (ret) {
> +		DRM_ERROR("cannot configure gpio_slp_n\n");
> +		return ret;
> +	}
> +
> +	ps_bridge->gpio_rst_n = devm_gpiod_get(&client->dev, "reset",
> +					       GPIOD_OUT_HIGH);
> +	if (IS_ERR(ps_bridge->gpio_rst_n)) {
> +		ret = PTR_ERR(ps_bridge->gpio_rst_n);
> +		DRM_ERROR("cannot get gpio_rst_n %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = gpiod_direction_output(ps_bridge->gpio_rst_n, 1);
> +	if (ret) {
> +		DRM_ERROR("cannot configure gpio_rst_n\n");
> +		return ret;
> +	}
> +
> +	ret = of_property_read_u32(dev->of_node, "reg", &temp_reg);
> +	if (ret) {
> +		DRM_ERROR("Can't read base_reg value\n");
> +		return ret;
> +	}
> +	ps_bridge->base_reg = temp_reg;
> +
> +	ps_bridge->bridge.funcs = &ps8640_bridge_funcs;
> +	ps_bridge->bridge.of_node = dev->of_node;
> +	ret = drm_bridge_add(&ps_bridge->bridge);
> +	if (ret) {
> +		DRM_ERROR("Failed to add bridge\n");
> +		return ret;
> +	}
> +
> +	i2c_set_clientdata(client, ps_bridge);
> +
> +	return 0;
> +}
> +
> +static int ps8640_remove(struct i2c_client *client)
> +{
> +	struct ps8640 *ps_bridge = i2c_get_clientdata(client);
> +
> +	drm_bridge_remove(&ps_bridge->bridge);
> +
> +	return 0;
> +}
> +
> +static const struct i2c_device_id ps8640_i2c_table[] = {
> +	{"parade,ps8640", 0},
> +	{},
> +};
> +MODULE_DEVICE_TABLE(i2c, ps8640_i2c_table);
> +
> +static const struct of_device_id ps8640_match[] = {
> +	{ .compatible = "parade,ps8640" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, ps8640_match);
> +
> +static struct i2c_driver ps8640_driver = {
> +	.id_table = ps8640_i2c_table,
> +	.probe = ps8640_probe,
> +	.remove = ps8640_remove,
> +	.driver = {
> +		.name = "parade,ps8640",
> +		.owner = THIS_MODULE,
> +		.of_match_table = ps8640_match,
> +	},
> +};
> +module_i2c_driver(ps8640_driver);
> +
> +MODULE_AUTHOR("Jitao Shi <jitao.shi at mediatek.com>");
> +MODULE_AUTHOR("CK Hu <ck.hu at mediatek.com>");
> +MODULE_DESCRIPTION("PARADE ps8640 DSI-eDP converter driver");
> +MODULE_LICENSE("GPL v2");





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