From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BB579C433C1 for ; Tue, 30 Mar 2021 15:28:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A7F76196A for ; Tue, 30 Mar 2021 15:28:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232082AbhC3P14 (ORCPT ); Tue, 30 Mar 2021 11:27:56 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:42750 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232413AbhC3P1d (ORCPT ); Tue, 30 Mar 2021 11:27:33 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: eballetbo) with ESMTPSA id 43F631F4594F Subject: Re: [PATCH v5 2/2] drm/bridge: anx7688: Add ANX7688 bridge driver support To: Dafna Hirschfeld , devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org Cc: a.hajda@samsung.com, narmstrong@baylibre.com, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@siol.net, airlied@linux.ie, daniel@ffwll.ch, chunkuang.hu@kernel.org, p.zabel@pengutronix.de, drinkcat@chromium.org, hsinyi@chromium.org, kernel@collabora.com, dafna3@gmail.com, robh+dt@kernel.org References: <20210305124351.15079-1-dafna.hirschfeld@collabora.com> <20210305124351.15079-3-dafna.hirschfeld@collabora.com> From: Enric Balletbo i Serra Message-ID: <5ba237ee-e5a0-6e33-4c2f-491bbd2b27c4@collabora.com> Date: Tue, 30 Mar 2021 17:27:28 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: <20210305124351.15079-3-dafna.hirschfeld@collabora.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Dafna, Thank you for your patch and to work on this. On 5/3/21 13:43, Dafna Hirschfeld wrote: > From: Enric Balletbo i Serra > > This driver adds support for the ANX7688 HDMI to DP converter block of the > ANX7688 device. > > For our use case, the only reason the Linux kernel driver is necessary is > to reject resolutions that require more bandwidth than what is available > on the DP side. DP bandwidth and lane count are reported by the bridge via > 2 registers and, as far as we know, only chips that have a firmware > version greater than 0.85 support these two registers. > Maybe we should mention that this driver can be extended to support the typec controller part which is not implemented right now because due our hardware configuration we can't test. > Signed-off-by: Nicolas Boichat > Signed-off-by: Hsin-Yi Wang > [The driver is OF only so should depends on CONFIG_OF] > Reported-by: kbuild test robot > Signed-off-by: Enric Balletbo i Serra > [convert the driver to be a i2c driver] > Signed-off-by: Dafna Hirschfeld > --- > drivers/gpu/drm/bridge/analogix/Kconfig | 11 ++ > drivers/gpu/drm/bridge/analogix/Makefile | 1 + > .../drm/bridge/analogix/analogix-anx7688.c | 186 ++++++++++++++++++ You put the binding in bindings/usb/analogix,anx7688.yaml, which I think is the right place. So to be coherent that should go under usb/typec. But we only implemented the HDMI to DP bridge part (port0) because is what we can really test. But this chip is more a typec controller than a bridge, so maybe it should be placed there. > 3 files changed, 198 insertions(+) > create mode 100644 drivers/gpu/drm/bridge/analogix/analogix-anx7688.c > > diff --git a/drivers/gpu/drm/bridge/analogix/Kconfig b/drivers/gpu/drm/bridge/analogix/Kconfig > index 024ea2a570e7..323327aabc38 100644 > --- a/drivers/gpu/drm/bridge/analogix/Kconfig > +++ b/drivers/gpu/drm/bridge/analogix/Kconfig > @@ -11,6 +11,17 @@ config DRM_ANALOGIX_ANX6345 > ANX6345 transforms the LVTTL RGB output of an > application processor to eDP or DisplayPort. > > +config DRM_ANALOGIX_ANX7688 > + tristate "Analogix ANX7688 bridge" > + depends on OF > + select DRM_KMS_HELPER > + select REGMAP_I2C > + help > + ANX7688 is an ultra-low power 4K Ultra-HD (4096x2160p60) > + mobile HD transmitter designed for portable > + devices. The ANX7688 converts HDMI 2.0 to > + DisplayPort 1.3 Ultra-HD. > + > config DRM_ANALOGIX_ANX78XX > tristate "Analogix ANX78XX bridge" > select DRM_ANALOGIX_DP > diff --git a/drivers/gpu/drm/bridge/analogix/Makefile b/drivers/gpu/drm/bridge/analogix/Makefile > index 44da392bb9f9..8f2272b8b732 100644 > --- a/drivers/gpu/drm/bridge/analogix/Makefile > +++ b/drivers/gpu/drm/bridge/analogix/Makefile > @@ -2,5 +2,6 @@ > analogix_dp-objs := analogix_dp_core.o analogix_dp_reg.o analogix-i2c-dptx.o > obj-$(CONFIG_DRM_ANALOGIX_ANX6345) += analogix-anx6345.o > obj-$(CONFIG_DRM_ANALOGIX_ANX7625) += anx7625.o > +obj-$(CONFIG_DRM_ANALOGIX_ANX7688) += analogix-anx7688.o > obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o > obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix_dp.o > diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx7688.c b/drivers/gpu/drm/bridge/analogix/analogix-anx7688.c > new file mode 100644 > index 000000000000..85a4b1a23035 > --- /dev/null > +++ b/drivers/gpu/drm/bridge/analogix/analogix-anx7688.c > @@ -0,0 +1,186 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * ANX7688 HDMI->DP bridge driver > + * > + * Copyright 2020 Google LLC > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* Register addresses */ > +#define ANX7688_VENDOR_ID_REG 0x00 > +#define ANX7688_DEVICE_ID_REG 0x02 > + > +#define ANX7688_FW_VERSION_REG 0x80 > + > +#define ANX7688_DP_BANDWIDTH_REG 0x85 > +#define ANX7688_DP_LANE_COUNT_REG 0x86 > + > +#define ANX7688_VENDOR_ID 0x1f29 > +#define ANX7688_DEVICE_ID 0x7688 > + > +/* First supported firmware version (0.85) */ > +#define ANX7688_MINIMUM_FW_VERSION 0x0085 > + > +static const struct regmap_config anx7688_regmap_config = { > + .reg_bits = 8, > + .val_bits = 8, > +}; > + > +struct anx7688 { > + struct i2c_client *client; > + struct regmap *regmap; > + struct drm_bridge bridge; > + bool filter; > +}; > + > +static inline struct anx7688 * > +bridge_to_anx7688(struct drm_bridge *bridge) > +{ > + return container_of(bridge, struct anx7688, bridge); > +} > + > +static bool anx7688_bridge_mode_fixup(struct drm_bridge *bridge, > + const struct drm_display_mode *mode, > + struct drm_display_mode *adjusted_mode) > +{ > + struct anx7688 *anx = bridge_to_anx7688(bridge); > + int totalbw, requiredbw; > + u8 dpbw, lanecount; > + u8 regs[2]; > + int ret; > + > + if (!anx->filter) > + return true; > + > + /* Read both regs 0x85 (bandwidth) and 0x86 (lane count). */ > + ret = regmap_bulk_read(anx->regmap, ANX7688_DP_BANDWIDTH_REG, regs, 2); > + if (ret < 0) { > + DRM_ERROR("Failed to read bandwidth/lane count\n"); > + return false; > + } > + dpbw = regs[0]; > + lanecount = regs[1]; > + > + /* Maximum 0x19 bandwidth (6.75 Gbps Turbo mode), 2 lanes */ > + if (dpbw > 0x19 || lanecount > 2) { > + DRM_ERROR("Invalid bandwidth/lane count (%02x/%d)\n", dpbw, > + lanecount); > + return false; > + } > + > + /* Compute available bandwidth (kHz) */ > + totalbw = dpbw * lanecount * 270000 * 8 / 10; > + > + /* Required bandwidth (8 bpc, kHz) */ > + requiredbw = mode->clock * 8 * 3; > + > + DRM_DEBUG_KMS("DP bandwidth: %d kHz (%02x/%d); mode requires %d Khz\n", > + totalbw, dpbw, lanecount, requiredbw); > + > + if (totalbw == 0) { > + DRM_ERROR("Bandwidth/lane count are 0, not rejecting modes\n"); > + return true; > + } > + > + return totalbw >= requiredbw; > +} > + > +static const struct drm_bridge_funcs anx7688_bridge_funcs = { > + .mode_fixup = anx7688_bridge_mode_fixup, > +}; > + > +static int anx7688_bridge_probe(struct i2c_client *client) > +{ > + struct device *dev = &client->dev; > + struct anx7688 *anx7688; > + u16 vendor, device, fw_version; > + u8 buffer[4]; > + int ret; > + > + anx7688 = devm_kzalloc(dev, sizeof(*anx7688), GFP_KERNEL); > + if (!anx7688) > + return -ENOMEM; > + > + anx7688->client = client; > + i2c_set_clientdata(client, anx7688); > + > + anx7688->regmap = devm_regmap_init_i2c(client, &anx7688_regmap_config); > + > + /* Read both vendor and device id (4 bytes). */ > + ret = regmap_bulk_read(anx7688->regmap, ANX7688_VENDOR_ID_REG, > + buffer, 4); > + if (ret) { > + dev_err(dev, "Failed to read chip vendor/device id\n"); > + return ret; > + } > + > + vendor = (u16)buffer[1] << 8 | buffer[0]; > + device = (u16)buffer[3] << 8 | buffer[2]; > + if (vendor != ANX7688_VENDOR_ID || device != ANX7688_DEVICE_ID) { > + dev_err(dev, "Invalid vendor/device id %04x/%04x\n", > + vendor, device); > + return -ENODEV; > + } > + > + ret = regmap_bulk_read(anx7688->regmap, ANX7688_FW_VERSION_REG, > + buffer, 2); > + if (ret) { > + dev_err(&client->dev, "Failed to read firmware version\n"); > + return ret; > + } > + > + fw_version = (u16)buffer[0] << 8 | buffer[1]; > + dev_info(dev, "ANX7688 firmware version 0x%04x\n", fw_version); > + > + anx7688->bridge.of_node = dev->of_node; > + > + /* FW version >= 0.85 supports bandwidth/lane count registers */ > + if (fw_version >= ANX7688_MINIMUM_FW_VERSION) > + anx7688->filter = true; > + else > + /* Warn, but not fail, for backwards compatibility */ > + DRM_WARN("Old ANX7688 FW version (0x%04x), not filtering\n", > + fw_version); > + > + anx7688->bridge.funcs = &anx7688_bridge_funcs; > + drm_bridge_add(&anx7688->bridge); > + > + return 0; > +} > + > +static int anx7688_bridge_remove(struct i2c_client *client) > +{ > + struct anx7688 *anx7688 = i2c_get_clientdata(client); > + > + drm_bridge_remove(&anx7688->bridge); > + > + return 0; > +} > + > +static const struct of_device_id anx7688_bridge_match_table[] = { > + { .compatible = "analogix,anx7688", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, anx7688_bridge_match_table); > + > +static struct i2c_driver anx7688_bridge_driver = { > + .probe_new = anx7688_bridge_probe, > + .remove = anx7688_bridge_remove, > + .driver = { > + .name = "anx7688-bridge", > + .of_match_table = anx7688_bridge_match_table, > + }, > +}; > + > +module_i2c_driver(anx7688_bridge_driver); > + > +MODULE_DESCRIPTION("ANX7688 HDMI->DP bridge driver"); > +MODULE_AUTHOR("Nicolas Boichat "); > +MODULE_AUTHOR("Enric Balletbo i Serra "); > +MODULE_LICENSE("GPL"); >