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

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@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@mediatek.com"); +MODULE_AUTHOR("CK Hu ck.hu@mediatek.com"); +MODULE_DESCRIPTION("PARADE ps8640 DSI-eDP converter driver"); +MODULE_LICENSE("GPL v2");