Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753121AbbLOG7H (ORCPT ); Tue, 15 Dec 2015 01:59:07 -0500 Received: from mail-vk0-f52.google.com ([209.85.213.52]:35132 "EHLO mail-vk0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752696AbbLOG7E (ORCPT ); Tue, 15 Dec 2015 01:59:04 -0500 MIME-Version: 1.0 In-Reply-To: <1450150210-21951-2-git-send-email-jitao.shi@mediatek.com> References: <1450150210-21951-1-git-send-email-jitao.shi@mediatek.com> <1450150210-21951-2-git-send-email-jitao.shi@mediatek.com> From: Daniel Kurtz Date: Tue, 15 Dec 2015 14:58:42 +0800 X-Google-Sender-Auth: Dpk1UlxTWLLqT92t3F9UqV5OEjg Message-ID: Subject: Re: [PATCH v6 2/2] drm/bridge: Add I2C based driver for ps8640 bridge To: Jitao Shi Cc: Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , David Airlie , Matthias Brugger , dri-devel , Andy Yan , Ajay Kumar , Vincent Palatin , cawa cheng , bibby.hsieh@mediatek.com, Russell King , Thierry Reding , "open list:OPEN FIRMWARE AND..." , linux-mediatek@lists.infradead.org, Yingjoe Chen , =?UTF-8?B?RWRkaWUgSHVhbmcgKOm7g+aZuuWCkSk=?= , "linux-arm-kernel@lists.infradead.org" , Rahul Sharma , srv_heupstream , "linux-kernel@vger.kernel.org" , Sascha Hauer Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 19697 Lines: 603 On Tue, Dec 15, 2015 at 11:30 AM, Jitao Shi wrote: > This patch adds drm_bridge driver for parade DSI to eDP bridge chip. > > Signed-off-by: Jitao Shi > --- > Changes since v5 > -fix compile errors when CONFIG_GPIOLIB=n > --- > drivers/gpu/drm/bridge/Kconfig | 10 + > drivers/gpu/drm/bridge/Makefile | 1 + > drivers/gpu/drm/bridge/parade-ps8640.c | 472 ++++++++++++++++++++++++++++++++ > 3 files changed, 483 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 6dddd39..dcfdbc9 100644 > --- a/drivers/gpu/drm/bridge/Kconfig > +++ b/drivers/gpu/drm/bridge/Kconfig > @@ -41,4 +41,14 @@ config DRM_PARADE_PS8622 > ---help--- > Parade eDP-LVDS bridge chip driver. > > +config DRM_PARADE_PS8640 > + tristate "Parade PS8640 MIPI DSI to eDP Converter" > + depends on OF > + 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 d4e28be..272e3c01 100644 > --- a/drivers/gpu/drm/bridge/Makefile > +++ b/drivers/gpu/drm/bridge/Makefile > @@ -4,3 +4,4 @@ obj-$(CONFIG_DRM_DW_HDMI) += dw_hdmi.o > obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw_hdmi-ahb-audio.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..bf0c3c37 > --- /dev/null > +++ b/drivers/gpu/drm/bridge/parade-ps8640.c > @@ -0,0 +1,472 @@ > +/* > + * 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 > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +#include > +#include > +#include > +#include > +#include > + > +#define PAGE2_GPIO_L 0xa6 > +#define PAGE2_GPIO_H 0xa7 > +#define PS_GPIO9 BIT(1) > +#define PAGE2_I2C_BYPASS 0xea > +#define I2C_BYPASS_EN 0xd0 > + > +#define PAGE3_SET_ADD 0xfe > +#define PAGE3_SET_VAL 0xff > +#define VDO_CTL_ADD 0x13 > +#define VDO_DIS 0x18 > +#define VDO_EN 0x1c > + > +#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 *page[6]; > + 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; > + bool enabled; > +}; > + > +static int ps8640_regr(struct i2c_client *client, u8 reg, u8 *value) > +{ > + int ret; > + > + ret = i2c_master_send(client, ®, 1); > + if (ret <= 0) { > + dev_err(&client->dev, "Failed to send i2c command, ret=%d\n", > + ret); > + return ret; > + } > + > + ret = i2c_master_recv(client, value, 1); > + if (ret <= 0) { > + dev_err(&client->dev, "Failed to recv i2c data, ret=%d\n", ret); > + return ret; > + } i2c_transfer should be a bit more efficient for reading one byte. > + > + return 0; > +} > + > +static int ps8640_regw(struct i2c_client *client, u8 reg, u8 value) > +{ > + int ret; > + char buf[2]; > + > + buf[0] = reg; > + buf[1] = value; > + ret = i2c_master_send(client, buf, ARRAY_SIZE(buf)); > + if (ret <= 0) { > + dev_err(&client->dev, "Failed to send i2c command, ret=%d\n", > + ret); > + return ret; > + } > + > + return 0; > +} > + > +static bool ps8640_check_valid_id(struct ps8640 *ps_bridge) > +{ > + struct i2c_client *client = ps_bridge->page[4]; > + u8 rev_id_low, rev_id_high, chip_id_low, chip_id_high; > + int retry_cnt = 0; > + > + do { > + ps8640_regr(client, PAGE4_CHIP_H, &chip_id_high); Check return value and propagate if non-zero. > + if (chip_id_high != 0x30) > + dev_info(&client->dev, "chip_id_high = 0x%x\n", > + chip_id_high); > + } while ((retry_cnt++ < 2) && (chip_id_high != 0x30)); Why is this loop retrying? What could be happening here? Please add a comment. > + > + ps8640_regr(client, PAGE4_REV_L, &rev_id_low); > + ps8640_regr(client, PAGE4_REV_H, &rev_id_high); > + ps8640_regr(client, PAGE4_CHIP_L, &chip_id_low); Can you just read all 4 bytes in a single i2c transaction? > + > + if ((rev_id_low == 0x00) && (rev_id_high == 0x0a) && > + (chip_id_low == 0x00) && (chip_id_high == 0x30)) > + return true; > + > + return false; return -ENODEV if no device is found? > +} > + > +static void ps8640_show_mcu_fw_version(struct ps8640 *ps_bridge) > +{ > + struct i2c_client *client = ps_bridge->page[5]; > + u8 major_ver, minor_ver; > + > + ps8640_regr(client, 0x4, &major_ver); > + ps8640_regr(client, 0x5, &minor_ver); Please #define these FW version registers. Also, can you read them in a single i2c transaction? > + > + 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->page[3]; > + > + if (ps8640_check_valid_id(ps_bridge)) { Usually it is prefered to fail fast, so: ret = ps8640_check_valid_id(ps_bridge); if (ret) return ret; ... return 0; > + ps8640_regw(client, PAGE3_SET_ADD, VDO_CTL_ADD); > + ps8640_regw(client, PAGE3_SET_VAL, VDO_DIS); Combine into 1 i2c transaction. > + ps8640_regw(client, PAGE3_SET_ADD, VDO_CTL_ADD); > + ps8640_regw(client, PAGE3_SET_VAL, VDO_DIS); Why are you doing this twice? Add a comment. > + return 0; > + } > + > + return -EINVAL; > +} > + > +static void ps8640_prepare(struct ps8640 *ps_bridge) > +{ > + struct i2c_client *client = ps_bridge->page[2]; > + int err, retry_cnt = 0; > + u8 set_vdo_done; > + > + if (ps_bridge->enabled) > + return; > + > + err = drm_panel_prepare(ps_bridge->panel); > + if (err < 0) { > + DRM_ERROR("failed to prepare panel: %d\n", err); > + return; > + } > + > + /* delay for power stable */ > + usleep_range(500, 700); > + > + err = regulator_enable(ps_bridge->pwr_1v2_supply); > + if (err < 0) { > + DRM_ERROR("failed to enable vdd12-supply: %d\n", err); > + goto err_panel_unprepare; > + } > + > + err = regulator_enable(ps_bridge->pwr_3v3_supply); > + if (err < 0) { > + DRM_ERROR("failed to enable vdd33-supply: %d\n", err); > + goto err_regulator_disable; Slightly less confusing: goto err_regulator_1v2_disable; > + } > + > + 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); 50 ms seems pretty slow polling interval. How long is this expected to take? > + ps8640_regr(client, 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; > + > + return; > + > +err_regulator_disable: > + regulator_disable(ps_bridge->pwr_1v2_supply); > +err_panel_unprepare: > + drm_panel_unprepare(ps_bridge->panel); > +} > + > +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); > + int err; > + > + ps8640_bdg_enable(ps_bridge); > + > + err = drm_panel_enable(ps_bridge->panel); > + if (err < 0) > + DRM_ERROR("failed to enable panel: %d\n", err); > +} > + > +static void ps8640_disable(struct drm_bridge *bridge) > +{ > + struct ps8640 *ps_bridge = bridge_to_ps8640(bridge); > + int err; > + > + if (!ps_bridge->enabled) > + return; > + > + ps_bridge->enabled = false; > + > + err = drm_panel_disable(ps_bridge->panel); > + if (err < 0) > + DRM_ERROR("failed to disable panel: %d\n", err); > + > + regulator_disable(ps_bridge->pwr_1v2_supply); > + regulator_disable(ps_bridge->pwr_3v3_supply); Not sure if it matters, but... since you enabled them 1v2 then 3v3, its usually better to turn them off in opposite order, so: 3v3 then 1v2. > + 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); > + int err; > + > + err = drm_panel_unprepare(ps_bridge->panel); > + if (err) > + DRM_ERROR("failed to unprepare panel: %d\n", err); > +} > + > +static int ps8640_get_modes(struct drm_connector *connector) > +{ > + struct ps8640 *ps_bridge = connector_to_ps8640(connector); > + struct i2c_client *client = ps_bridge->page[2]; > + > + ps8640_prepare(ps_bridge); > + ps8640_regw(client, PAGE2_I2C_BYPASS, I2C_BYPASS_EN); Do you need to unset bypass mode after getting modes? If not, perhaps you can just set this once during prepare? > + > + 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 = { Indentation looks a bit funny. I think you want another tab here. > + .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; Always? > +} > + > +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: %d\n", ret); > + 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 *port, *out_ep; > + struct device_node *panel_node = NULL; > + int i, ret; > + > + ps_bridge = devm_kzalloc(dev, sizeof(*ps_bridge), GFP_KERNEL); > + if (!ps_bridge) > + return -ENOMEM; > + > + /* port@1 is ps8640 output port */ > + port = of_graph_get_port_by_id(np, 1); > + if (port) { > + out_ep = of_get_child_by_name(port, "endpoint"); > + of_node_put(port); > + 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->page[0] = client; > + for (i = 1; i < 6; i++) > + ps_bridge->page[i] = i2c_new_dummy(client->adapter, > + client->addr + i); Can you add a comment somewhere explaining what these extra i2c clients are for? Also, if after this in probe() fails, unregister our these i2c_clients. Or, move this after the devm_*() calls. > + > + ps_bridge->pwr_3v3_supply = devm_regulator_get(dev, "vdd33"); > + if (IS_ERR(ps_bridge->pwr_3v3_supply)) { > + ret = PTR_ERR(ps_bridge->pwr_3v3_supply); > + dev_err(dev, "cannot get vdd33 supply: %d\n", ret); > + return ret; > + } > + > + ps_bridge->pwr_1v2_supply = devm_regulator_get(dev, "vdd12"); > + if (IS_ERR(ps_bridge->pwr_1v2_supply)) { > + ret = PTR_ERR(ps_bridge->pwr_1v2_supply); > + dev_err(dev, "cannot get vdd12 supply: %d\n", ret); > + return ret; > + } > + > + 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); > + dev_err(dev, "cannot get gpio_mode_sel_n %d\n", ret); > + return ret; > + } > + > + ps_bridge->gpio_slp_n = devm_gpiod_get(&client->dev, "sleep", > + GPIOD_OUT_HIGH); > + if (IS_ERR(ps_bridge->gpio_slp_n)) { > + ret = PTR_ERR(ps_bridge->gpio_slp_n); > + dev_err(dev, "cannot get gpio_slp_n: %d\n", ret); > + 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); > + dev_err(dev, "cannot get gpio_rst_n: %d\n", ret); > + return ret; > + } > + > + ps_bridge->bridge.funcs = &ps8640_bridge_funcs; > + ps_bridge->bridge.of_node = dev->of_node; > + ret = drm_bridge_add(&ps_bridge->bridge); > + if (ret) { > + dev_err(dev, "Failed to add bridge: %d\n", ret); > + 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); > + i2c_unregister_device() the pages. > + 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", > + .of_match_table = ps8640_match, > + }, > +}; > +module_i2c_driver(ps8640_driver); > + > +MODULE_AUTHOR("Jitao Shi "); > +MODULE_AUTHOR("CK Hu "); > +MODULE_DESCRIPTION("PARADE ps8640 DSI-eDP converter driver"); > +MODULE_LICENSE("GPL v2"); > -- > 1.7.9.5 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/dri-devel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/