From patchwork Tue Nov 28 08:42:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 13470669 Received: from mail-pl1-f181.google.com (mail-pl1-f181.google.com [209.85.214.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BB7B4134D7 for ; Tue, 28 Nov 2023 08:45:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="mnntOhVs" Received: by mail-pl1-f181.google.com with SMTP id d9443c01a7336-1cfa5840db3so32202905ad.2 for ; Tue, 28 Nov 2023 00:45:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1701161106; x=1701765906; darn=lists.linux.dev; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=kHxxwveZDRAPnfOWumxXktb5k7NbUjKgtDpJO55ZaA8=; b=mnntOhVsAa4m7xHEWzPSBdZUUrkBTYIhxgC+rue/VQ4KJe3fv9GtSa+OIztZliYOyM tQGapkIjdSYSDmQiMZ8664w117ZuW/Y+IL+OO6HxS0750diKQ2bxbcHcNudFfupdeEP1 ewsoKvltvTFkGETb4NULgjwGHBXvM+gMO4r8g= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1701161106; x=1701765906; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=kHxxwveZDRAPnfOWumxXktb5k7NbUjKgtDpJO55ZaA8=; b=UHueOEGQVgYFx0cF8xmRO/rX7BvYoiRNs5hjMaK5i+nvgGwVvPY7+zCmvRHZ4nsnhg +a+4SMnv214BTYRcl8VFWdhO2LRAHBEN7GdzMIrKSoSuvbLdtgeuKybBrcp8hC31T56i A7R6p8LSHARHsuM6S3TtMNC8xcdvPC3i2KSq2xz03lL+1uIKaU+SHjNmNhmQ+mi73CoR pZp4UQhPrYCR2zFaxDrWvHps0G/v1ufxMwCvbiwtYFEo1aZ1KHM/o1CA+ezFWWkZiQpR BTrCK/204sRgD/XZtebwdt9nyCMScNxc9ox7inIbUjm6KjoAY4n/WUxhvUi6LSTnmmb1 hxQQ== X-Gm-Message-State: AOJu0YxwR/Jq16msHRxWNLffYdxayYEBDBttjQ8TwH9VHNZ8QOIFSYox ekwC182JaJ2DlEyfkbL3Pkcejg== X-Google-Smtp-Source: AGHT+IFwNRanqg6iNjPiAn8C7xAInJUbYOtL1AJjn6XOh76hm70XQlF/qqZTYAqMlV2R/DvAZERpiQ== X-Received: by 2002:a17:902:d2c1:b0:1cf:ccc3:c9d7 with SMTP id n1-20020a170902d2c100b001cfccc3c9d7mr7924520plc.3.1701161106024; Tue, 28 Nov 2023 00:45:06 -0800 (PST) Received: from wenstp920.tpe.corp.google.com ([2401:fa00:1:10:a990:1e95:a915:9c70]) by smtp.gmail.com with ESMTPSA id j1-20020a170902c08100b001ab39cd875csm8358074pld.133.2023.11.28.00.45.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Nov 2023 00:45:05 -0800 (PST) From: Chen-Yu Tsai To: Rob Herring , Frank Rowand , Krzysztof Kozlowski , Conor Dooley , Matthias Brugger , AngeloGioacchino Del Regno , Wolfram Sang , Benson Leung , Tzung-Bi Shih Cc: Chen-Yu Tsai , chrome-platform@lists.linux.dev, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Douglas Anderson , Johan Hovold , Hsin-Yi Wang , Dmitry Torokhov , andriy.shevchenko@linux.intel.com, Jiri Kosina , linus.walleij@linaro.org, broonie@kernel.org, gregkh@linuxfoundation.org, hdegoede@redhat.com, james.clark@arm.com, james@equiv.tech, keescook@chromium.org, rafael@kernel.org, tglx@linutronix.de, Jeff LaBundy , linux-input@vger.kernel.org, linux-i2c@vger.kernel.org Subject: [RFC PATCH v3 1/5] of: dynamic: Add of_changeset_update_prop_string Date: Tue, 28 Nov 2023 16:42:30 +0800 Message-ID: <20231128084236.157152-2-wenst@chromium.org> X-Mailer: git-send-email 2.43.0.rc1.413.gea7ed67945-goog In-Reply-To: <20231128084236.157152-1-wenst@chromium.org> References: <20231128084236.157152-1-wenst@chromium.org> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add a helper function to add string property updates to an OF changeset. This is similar to of_changeset_add_prop_string(), but instead of adding the property (and failing if it exists), it will update the property. This shall be used later in the DT hardware prober. Signed-off-by: Chen-Yu Tsai --- New patch added in v3. --- drivers/of/dynamic.c | 47 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/of.h | 3 +++ 2 files changed, 50 insertions(+) diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c index f63250c650ca..d22aad938667 100644 --- a/drivers/of/dynamic.c +++ b/drivers/of/dynamic.c @@ -1039,3 +1039,50 @@ int of_changeset_add_prop_u32_array(struct of_changeset *ocs, return ret; } EXPORT_SYMBOL_GPL(of_changeset_add_prop_u32_array); + +static int of_changeset_update_prop_helper(struct of_changeset *ocs, + struct device_node *np, + const struct property *pp) +{ + struct property *new_pp; + int ret; + + new_pp = __of_prop_dup(pp, GFP_KERNEL); + if (!new_pp) + return -ENOMEM; + + ret = of_changeset_update_property(ocs, np, new_pp); + if (ret) { + kfree(new_pp->name); + kfree(new_pp->value); + kfree(new_pp); + } + + return ret; +} + +/** + * of_changeset_update_prop_string - Add a string property update to a changeset + * + * @ocs: changeset pointer + * @np: device node pointer + * @prop_name: name of the property to be updated + * @str: pointer to null terminated string + * + * Create a string property to be updated and add it to a changeset. + * + * Return: 0 on success, a negative error value in case of an error. + */ +int of_changeset_update_prop_string(struct of_changeset *ocs, + struct device_node *np, + const char *prop_name, const char *str) +{ + struct property prop; + + prop.name = (char *)prop_name; + prop.length = strlen(str) + 1; + prop.value = (void *)str; + + return of_changeset_update_prop_helper(ocs, np, &prop); +} +EXPORT_SYMBOL_GPL(of_changeset_update_prop_string); diff --git a/include/linux/of.h b/include/linux/of.h index 6a9ddf20e79a..c69bc7da380e 100644 --- a/include/linux/of.h +++ b/include/linux/of.h @@ -1601,6 +1601,9 @@ static inline int of_changeset_add_prop_u32(struct of_changeset *ocs, { return of_changeset_add_prop_u32_array(ocs, np, prop_name, &val, 1); } +int of_changeset_update_prop_string(struct of_changeset *ocs, + struct device_node *np, + const char *prop_name, const char *str); #else /* CONFIG_OF_DYNAMIC */ static inline int of_reconfig_notifier_register(struct notifier_block *nb) From patchwork Tue Nov 28 08:42:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 13470670 Received: from mail-pl1-f169.google.com (mail-pl1-f169.google.com [209.85.214.169]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D23C8199B2 for ; 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Tue, 28 Nov 2023 00:45:10 -0800 (PST) From: Chen-Yu Tsai To: Rob Herring , Frank Rowand , Krzysztof Kozlowski , Conor Dooley , Matthias Brugger , AngeloGioacchino Del Regno , Wolfram Sang , Benson Leung , Tzung-Bi Shih Cc: Chen-Yu Tsai , chrome-platform@lists.linux.dev, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Douglas Anderson , Johan Hovold , Hsin-Yi Wang , Dmitry Torokhov , andriy.shevchenko@linux.intel.com, Jiri Kosina , linus.walleij@linaro.org, broonie@kernel.org, gregkh@linuxfoundation.org, hdegoede@redhat.com, james.clark@arm.com, james@equiv.tech, keescook@chromium.org, rafael@kernel.org, tglx@linutronix.de, Jeff LaBundy , linux-input@vger.kernel.org, linux-i2c@vger.kernel.org Subject: [RFC PATCH v3 2/5] i2c: of: Introduce component probe function Date: Tue, 28 Nov 2023 16:42:31 +0800 Message-ID: <20231128084236.157152-3-wenst@chromium.org> X-Mailer: git-send-email 2.43.0.rc1.413.gea7ed67945-goog In-Reply-To: <20231128084236.157152-1-wenst@chromium.org> References: <20231128084236.157152-1-wenst@chromium.org> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Some devices are designed and manufactured with some components having multiple drop-in replacement options. These components are often connected to the mainboard via ribbon cables, having the same signals and pin assignments across all options. These may include the display panel and touchscreen on laptops and tablets, and the trackpad on laptops. Sometimes which component option is used in a particular device can be detected by some firmware provided identifier, other times that information is not available, and the kernel has to try to probe each device. This change attempts to make the "probe each device" case cleaner. The current approach is to have all options added and enabled in the device tree. The kernel would then bind each device and run each driver's probe function. This works, but has been broken before due to the introduction of asynchronous probing, causing multiple instances requesting "shared" resources, such as pinmuxes, GPIO pins, interrupt lines, at the same time, with only one instance succeeding. Work arounds for these include moving the pinmux to the parent I2C controller, using GPIO hogs or pinmux settings to keep the GPIO pins in some fixed configuration, and requesting the interrupt line very late. Such configurations can be seen on the MT8183 Krane Chromebook tablets, and the Qualcomm sc8280xp-based Lenovo Thinkpad 13S. Instead of this delicate dance between drivers and device tree quirks, this change introduces a simple I2C component probe. function For a given class of devices on the same I2C bus, it will go through all of them, doing a simple I2C read transfer and see which one of them responds. It will then enable the device that responds. This requires some minor modifications in the existing device tree. The status for all the device nodes for the component options must be set to "failed-needs-probe". This makes it clear that some mechanism is needed to enable one of them, and also prevents the prober and device drivers running at the same time. Signed-off-by: Chen-Yu Tsai --- Changes since v2: - New patch split out from "of: Introduce hardware prober driver" - Addressed Rob's comments - Move i2c prober to i2c subsystem - Use of_node_is_available() to check if node is enabled. - Use OF changeset API to update status property - Addressed Andy's comments - Probe function now accepts "struct device *dev" instead to reduce line length and dereferences - Move "ret = 0" to just before for_each_child_of_node(i2c_node, node) --- drivers/i2c/i2c-core-of.c | 110 ++++++++++++++++++++++++++++++++++++++ include/linux/i2c.h | 4 ++ 2 files changed, 114 insertions(+) diff --git a/drivers/i2c/i2c-core-of.c b/drivers/i2c/i2c-core-of.c index a6c407d36800..3a0b4986c585 100644 --- a/drivers/i2c/i2c-core-of.c +++ b/drivers/i2c/i2c-core-of.c @@ -217,4 +217,114 @@ static int of_i2c_notify(struct notifier_block *nb, unsigned long action, struct notifier_block i2c_of_notifier = { .notifier_call = of_i2c_notify, }; + +/* + * Some devices, such as Google Hana Chromebooks, are produced by multiple + * vendors each using their preferred components. Such components are all + * in the device tree. Instead of having all of them enabled and having each + * driver separately try and probe its device while fighting over shared + * resources, they can be marked as "fail-needs-probe" and have a prober + * figure out which one is actually used beforehand. + * + * This prober assumes such drop-in parts are on the same I2C bus, have + * non-conflicting addresses, and can be directly probed by seeing which + * address responds. + * + * TODO: + * - Support handling common regulators and GPIOs. + * - Support I2C muxes + */ + +/** + * i2c_of_probe_component() - probe for devices of "type" on the same i2c bus + * @dev: &struct device of the caller, only used for dev_* printk messages + * @type: a string to match the device node name prefix to probe for + * + * Probe for possible I2C components of the same "type" on the same I2C bus + * that have their status marked as "fail". + */ +int i2c_of_probe_component(struct device *dev, const char *type) +{ + struct device_node *node, *i2c_node; + struct i2c_adapter *i2c; + struct of_changeset *ocs = NULL; + int ret; + + node = of_find_node_by_name(NULL, type); + if (!node) + return dev_err_probe(dev, -ENODEV, "Could not find %s device node\n", type); + + i2c_node = of_get_next_parent(node); + if (!of_node_name_eq(i2c_node, "i2c")) { + of_node_put(i2c_node); + return dev_err_probe(dev, -EINVAL, "%s device isn't on I2C bus\n", type); + } + + for_each_child_of_node(i2c_node, node) { + if (!of_node_name_prefix(node, type)) + continue; + if (of_device_is_available(node)) { + /* + * Device tree has component already enabled. Either the + * device tree isn't supported or we already probed once. + */ + of_node_put(node); + of_node_put(i2c_node); + return 0; + } + } + + i2c = of_get_i2c_adapter_by_node(i2c_node); + if (!i2c) { + of_node_put(i2c_node); + return dev_err_probe(dev, -EPROBE_DEFER, "Couldn't get I2C adapter\n"); + } + + ret = 0; + for_each_child_of_node(i2c_node, node) { + union i2c_smbus_data data; + u32 addr; + + if (!of_node_name_prefix(node, type)) + continue; + if (of_property_read_u32(node, "reg", &addr)) + continue; + if (i2c_smbus_xfer(i2c, addr, 0, I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &data) < 0) + continue; + + dev_info(dev, "Enabling %pOF\n", node); + + ocs = kzalloc(sizeof(*ocs), GFP_KERNEL); + if (!ocs) { + ret = -ENOMEM; + goto err_put_node; + } + + /* Found a device that is responding */ + of_changeset_init(ocs); + ret = of_changeset_update_prop_string(ocs, node, "status", "okay"); + if (ret) + goto err_free_ocs; + ret = of_changeset_apply(ocs); + if (ret) + goto err_destroy_ocs; + + of_node_put(node); + break; + } + + i2c_put_adapter(i2c); + of_node_put(i2c_node); + + return 0; + +err_destroy_ocs: + of_changeset_destroy(ocs); +err_free_ocs: + kfree(ocs); +err_put_node: + of_node_put(node); + return ret; +} +EXPORT_SYMBOL_GPL(i2c_of_probe_component); #endif /* CONFIG_OF_DYNAMIC */ diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 0dae9db27538..75fbbd5a4b15 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -997,6 +997,10 @@ const struct of_device_id int of_i2c_get_board_info(struct device *dev, struct device_node *node, struct i2c_board_info *info); +#if IS_ENABLED(CONFIG_OF_DYNAMIC) +int i2c_of_probe_component(struct device *dev, const char *type); +#endif + #else static inline struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) From patchwork Tue Nov 28 08:42:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 13470671 Received: from mail-pg1-f180.google.com (mail-pg1-f180.google.com [209.85.215.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1A9D819464 for ; 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Tue, 28 Nov 2023 00:45:15 -0800 (PST) From: Chen-Yu Tsai To: Rob Herring , Frank Rowand , Krzysztof Kozlowski , Conor Dooley , Matthias Brugger , AngeloGioacchino Del Regno , Wolfram Sang , Benson Leung , Tzung-Bi Shih Cc: Chen-Yu Tsai , chrome-platform@lists.linux.dev, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Douglas Anderson , Johan Hovold , Hsin-Yi Wang , Dmitry Torokhov , andriy.shevchenko@linux.intel.com, Jiri Kosina , linus.walleij@linaro.org, broonie@kernel.org, gregkh@linuxfoundation.org, hdegoede@redhat.com, james.clark@arm.com, james@equiv.tech, keescook@chromium.org, rafael@kernel.org, tglx@linutronix.de, Jeff LaBundy , linux-input@vger.kernel.org, linux-i2c@vger.kernel.org Subject: [RFC PATCH v3 3/5] platform/chrome: Introduce device tree hardware prober Date: Tue, 28 Nov 2023 16:42:32 +0800 Message-ID: <20231128084236.157152-4-wenst@chromium.org> X-Mailer: git-send-email 2.43.0.rc1.413.gea7ed67945-goog In-Reply-To: <20231128084236.157152-1-wenst@chromium.org> References: <20231128084236.157152-1-wenst@chromium.org> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Some devices are designed and manufactured with some components having multiple drop-in replacement options. These components are often connected to the mainboard via ribbon cables, having the same signals and pin assignments across all options. These may include the display panel and touchscreen on laptops and tablets, and the trackpad on laptops. Sometimes which component option is used in a particular device can be detected by some firmware provided identifier, other times that information is not available, and the kernel has to try to probe each device. This change attempts to make the "probe each device" case cleaner. The current approach is to have all options added and enabled in the device tree. The kernel would then bind each device and run each driver's probe function. This works, but has been broken before due to the introduction of asynchronous probing, causing multiple instances requesting "shared" resources, such as pinmuxes, GPIO pins, interrupt lines, at the same time, with only one instance succeeding. Work arounds for these include moving the pinmux to the parent I2C controller, using GPIO hogs or pinmux settings to keep the GPIO pins in some fixed configuration, and requesting the interrupt line very late. Such configurations can be seen on the MT8183 Krane Chromebook tablets, and the Qualcomm sc8280xp-based Lenovo Thinkpad 13S. Instead of this delicate dance between drivers and device tree quirks, this change introduces a simple I2C component prober. For any given class of devices on the same I2C bus, it will go through all of them, doing a simple I2C read transfer and see which one of them responds. It will then enable the device that responds. This requires some minor modifications in the existing device tree. The status for all the device nodes for the component options must be set to "failed-needs-probe". This makes it clear that some mechanism is needed to enable one of them, and also prevents the prober and device drivers running at the same time. Signed-off-by: Chen-Yu Tsai --- Changes since v2: - Addressed Rob's comments - Move remaining driver code to drivers/platform/chrome/ - Depend on rather than select CONFIG_I2C - Copy machine check to driver init function - Addressed Andy's comments - Explicitly mention "device tree" or OF in driver name, description and Kconfig symbol - Drop filename from inside the file - Switch to passing "struct device *" to shorten lines - Move "ret = 0" to just before for_each_child_of_node(i2c_node, node) - Make loop variable size_t (instead of unsigned int as Andy asked) - Use PLATFORM_DEVID_NONE instead of raw -1 - Use standard goto error path pattern in hw_prober_driver_init() - Changes since v1: - New patch --- drivers/platform/chrome/Kconfig | 11 +++ drivers/platform/chrome/Makefile | 1 + .../platform/chrome/chromeos_of_hw_prober.c | 89 +++++++++++++++++++ 3 files changed, 101 insertions(+) create mode 100644 drivers/platform/chrome/chromeos_of_hw_prober.c diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig index 7a83346bfa53..aa161f2f09e3 100644 --- a/drivers/platform/chrome/Kconfig +++ b/drivers/platform/chrome/Kconfig @@ -61,6 +61,17 @@ config CHROMEOS_TBMC To compile this driver as a module, choose M here: the module will be called chromeos_tbmc. +config CHROMEOS_OF_HW_PROBER + bool "ChromeOS Device Tree Hardware Prober" + depends on OF + depends on I2C + select OF_DYNAMIC + default OF + help + This option enables the device tree hardware prober for ChromeOS + devices. The driver will probe the correct component variant in + devices that have multiple drop-in options for one component. + config CROS_EC tristate "ChromeOS Embedded Controller" select CROS_EC_PROTO diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile index 2dcc6ccc2302..21a9d5047053 100644 --- a/drivers/platform/chrome/Makefile +++ b/drivers/platform/chrome/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_CHROMEOS_ACPI) += chromeos_acpi.o obj-$(CONFIG_CHROMEOS_LAPTOP) += chromeos_laptop.o obj-$(CONFIG_CHROMEOS_PRIVACY_SCREEN) += chromeos_privacy_screen.o obj-$(CONFIG_CHROMEOS_PSTORE) += chromeos_pstore.o +obj-$(CONFIG_CHROMEOS_OF_HW_PROBER) += chromeos_of_hw_prober.o obj-$(CONFIG_CHROMEOS_TBMC) += chromeos_tbmc.o obj-$(CONFIG_CROS_EC) += cros_ec.o obj-$(CONFIG_CROS_EC_I2C) += cros_ec_i2c.o diff --git a/drivers/platform/chrome/chromeos_of_hw_prober.c b/drivers/platform/chrome/chromeos_of_hw_prober.c new file mode 100644 index 000000000000..13aaad6382aa --- /dev/null +++ b/drivers/platform/chrome/chromeos_of_hw_prober.c @@ -0,0 +1,89 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ChromeOS Device Tree Hardware Prober + * + * Copyright (c) 2023 Google LLC + */ + +#include +#include +#include +#include + +#define DRV_NAME "chromeos_of_hw_prober" + +/** + * struct hw_prober_entry - Holds an entry for the hardware prober + * + * @compatible: compatible string to match against the machine + * @prober: prober function to call when machine matches + * @data: extra data for the prober function + */ +struct hw_prober_entry { + const char *compatible; + int (*prober)(struct device *dev, const void *data); + const void *data; +}; + +static int chromeos_i2c_component_prober(struct device *dev, const void *data) +{ + const char *type = data; + + return i2c_of_probe_component(dev, type); +} + +static const struct hw_prober_entry hw_prober_platforms[] = { + { .compatible = "google,hana", .prober = chromeos_i2c_component_prober, .data = "touchscreen" }, + { .compatible = "google,hana", .prober = chromeos_i2c_component_prober, .data = "trackpad" }, +}; + +static int chromeos_of_hw_prober_probe(struct platform_device *pdev) +{ + for (size_t i = 0; i < ARRAY_SIZE(hw_prober_platforms); i++) + if (of_machine_is_compatible(hw_prober_platforms[i].compatible)) { + int ret; + + ret = hw_prober_platforms[i].prober(&pdev->dev, + hw_prober_platforms[i].data); + if (ret) + return ret; + } + + return 0; +} + +static struct platform_driver chromeos_of_hw_prober_driver = { + .probe = chromeos_of_hw_prober_probe, + .driver = { + .name = DRV_NAME, + }, +}; + +static int __init chromeos_of_hw_prober_driver_init(void) +{ + struct platform_device *pdev; + size_t i; + int ret; + + for (i = 0; i < ARRAY_SIZE(hw_prober_platforms); i++) + if (of_machine_is_compatible(hw_prober_platforms[i].compatible)) + break; + if (i == ARRAY_SIZE(hw_prober_platforms)) + return 0; + + ret = platform_driver_register(&chromeos_of_hw_prober_driver); + if (ret) + return ret; + + pdev = platform_device_register_simple(DRV_NAME, PLATFORM_DEVID_NONE, NULL, 0); + if (IS_ERR(pdev)) + goto err; + + return 0; + +err: + platform_driver_unregister(&chromeos_of_hw_prober_driver); + + return PTR_ERR(pdev); +} +device_initcall(chromeos_of_hw_prober_driver_init); From patchwork Tue Nov 28 08:42:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen-Yu Tsai X-Patchwork-Id: 13470672 Received: from mail-pl1-f181.google.com (mail-pl1-f181.google.com [209.85.214.181]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 15780199CA for ; 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Tue, 28 Nov 2023 00:45:21 -0800 (PST) From: Chen-Yu Tsai To: Rob Herring , Frank Rowand , Krzysztof Kozlowski , Conor Dooley , Matthias Brugger , AngeloGioacchino Del Regno , Wolfram Sang , Benson Leung , Tzung-Bi Shih Cc: Chen-Yu Tsai , chrome-platform@lists.linux.dev, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Douglas Anderson , Johan Hovold , Hsin-Yi Wang , Dmitry Torokhov , andriy.shevchenko@linux.intel.com, Jiri Kosina , linus.walleij@linaro.org, broonie@kernel.org, gregkh@linuxfoundation.org, hdegoede@redhat.com, james.clark@arm.com, james@equiv.tech, keescook@chromium.org, rafael@kernel.org, tglx@linutronix.de, Jeff LaBundy , linux-input@vger.kernel.org, linux-i2c@vger.kernel.org Subject: [RFC PATCH v3 4/5] arm64: dts: mediatek: mt8173-elm-hana: Mark touchscreens and trackpads as fail Date: Tue, 28 Nov 2023 16:42:33 +0800 Message-ID: <20231128084236.157152-5-wenst@chromium.org> X-Mailer: git-send-email 2.43.0.rc1.413.gea7ed67945-goog In-Reply-To: <20231128084236.157152-1-wenst@chromium.org> References: <20231128084236.157152-1-wenst@chromium.org> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Instead of having them all available, mark them all as "fail-needs-probe" and have the implementation try to probe which one is present. Signed-off-by: Chen-Yu Tsai --- Changes since v2: - Drop class from status --- arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi b/arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi index bdcd35cecad9..1d68bc6834e4 100644 --- a/arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi +++ b/arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi @@ -15,6 +15,7 @@ touchscreen2: touchscreen@34 { reg = <0x34>; interrupt-parent = <&pio>; interrupts = <88 IRQ_TYPE_LEVEL_LOW>; + status = "fail-needs-probe"; }; /* @@ -28,6 +29,7 @@ touchscreen3: touchscreen@20 { hid-descr-addr = <0x0020>; interrupt-parent = <&pio>; interrupts = <88 IRQ_TYPE_LEVEL_LOW>; + status = "fail-needs-probe"; }; }; @@ -44,6 +46,7 @@ trackpad2: trackpad@2c { reg = <0x2c>; hid-descr-addr = <0x0020>; wakeup-source; + status = "fail-needs-probe"; }; }; @@ -68,3 +71,11 @@ pins_wp { }; }; }; + +&touchscreen { + status = "fail-needs-probe"; 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Tue, 28 Nov 2023 00:45:26 -0800 (PST) Received: from wenstp920.tpe.corp.google.com ([2401:fa00:1:10:a990:1e95:a915:9c70]) by smtp.gmail.com with ESMTPSA id j1-20020a170902c08100b001ab39cd875csm8358074pld.133.2023.11.28.00.45.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Nov 2023 00:45:26 -0800 (PST) From: Chen-Yu Tsai To: Rob Herring , Frank Rowand , Krzysztof Kozlowski , Conor Dooley , Matthias Brugger , AngeloGioacchino Del Regno , Wolfram Sang , Benson Leung , Tzung-Bi Shih Cc: Chen-Yu Tsai , chrome-platform@lists.linux.dev, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, Douglas Anderson , Johan Hovold , Hsin-Yi Wang , Dmitry Torokhov , andriy.shevchenko@linux.intel.com, Jiri Kosina , linus.walleij@linaro.org, broonie@kernel.org, gregkh@linuxfoundation.org, hdegoede@redhat.com, james.clark@arm.com, james@equiv.tech, keescook@chromium.org, rafael@kernel.org, tglx@linutronix.de, Jeff LaBundy , linux-input@vger.kernel.org, linux-i2c@vger.kernel.org Subject: [RFC PATCH v3 5/5] arm64: dts: mediatek: mt8173-elm-hana: Add G2touch G7500 touchscreen Date: Tue, 28 Nov 2023 16:42:34 +0800 Message-ID: <20231128084236.157152-6-wenst@chromium.org> X-Mailer: git-send-email 2.43.0.rc1.413.gea7ed67945-goog In-Reply-To: <20231128084236.157152-1-wenst@chromium.org> References: <20231128084236.157152-1-wenst@chromium.org> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 This introduces yet another second-source touchscreen found on Hana. This is a G2touch G7500 touchscreen, which is compatible with HID over I2C. Add a device node for it. In keeping with the new scheme for second source components, mark it as "failed-needs-probe". Signed-off-by: Chen-Yu Tsai --- Changes since v2: - Drop class from status --- arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi b/arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi index 1d68bc6834e4..216d8b43be05 100644 --- a/arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi +++ b/arch/arm64/boot/dts/mediatek/mt8173-elm-hana.dtsi @@ -31,6 +31,15 @@ touchscreen3: touchscreen@20 { interrupts = <88 IRQ_TYPE_LEVEL_LOW>; status = "fail-needs-probe"; }; + + touchscreen4: touchscreen@40 { + compatible = "hid-over-i2c"; + reg = <0x40>; + hid-descr-addr = <0x0001>; + interrupt-parent = <&pio>; + interrupts = <88 IRQ_TYPE_LEVEL_LOW>; + status = "fail-needs-probe"; + }; }; &i2c4 {