From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A52ED35E1AC; Mon, 21 Sep 2026 04:23:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789964612; cv=none; b=fxdQaAvsivKjnaZh6KN550FKfWpbA7itRnK6tLh1g2eUsOPZNPekhIDlCdMmpXoTeBMPPvr+1iBKaQcC2aA09OF6xuOyjk6tM4K43NpWDR64J/0MY96kTPDtzRBZZtuc+bf4GBJO5D1qIoaM/mqqqvEGGaXSEW+qSkQlj8V/7Zs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789964612; c=relaxed/simple; bh=jvbL/2RiMhg7JLG9DBXG5C6oQ3baY2PtbvCk8gshE7A=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=YdWKXZ8/XD9LciNSOCOBHh410NRQlVf55iNtdXw/FXhCPCAGOhRdN+F74Bs5HuTtq5L6AclnhbcnpQgu5eT1iebuh3WWlQ0cN52YBlCsVfVTDbazTbf6IFuRJe/beGVgNP+t9d6OcfjooslNbuOAd1+PwD05BokPvs1c7GUMEdk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=phF9+0Q2; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="phF9+0Q2" Received: by smtp.kernel.org (Postfix) with ESMTPS id 7F08AC2BCFD; Mon, 21 Sep 2026 04:23:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1789964612; bh=jvbL/2RiMhg7JLG9DBXG5C6oQ3baY2PtbvCk8gshE7A=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=phF9+0Q2K4HXelrK4K49nidam5whFox+Kjs9MzfpeY95KmUrrLLBxaaMO9ZzIniUL JcGJNuMA8EMYzu5MrMsCT0ofTWgv+VGl6rjgbQA0NE/Gvv7oyoadDjZI8jPuY1/JTK Y2AnkBcRvzNMMy1ADCVjT6cq2E06bk5ennI/TBQU1TxFyqrJNWmKPhxoMTKR9YEe4M CM7uv/yh51bqdJq7YGbKD4B8+qsEdC6dIbkIO4GIu3b/GuSLMgTe9fbwG5uiCkSByD 2eh6ChfJjprXR7Vs4WVbAgFgb4p85176q43ra0Rf3Mj3qYiTwwPF0KY2XoufJ9mgnt Ty7lEyWa2NKTw== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68354C982F2; Mon, 21 Sep 2026 04:23:32 +0000 (UTC) From: Long Zhao via B4 Relay Date: Mon, 21 Sep 2026 12:23:27 +0800 Subject: [PATCH v8 08/18] gpiolib: regmap: add write_data_after_dir quirk Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260921-cv75-v5-v8-8-282ff5d98dda@ambarella.com> References: <20260921-cv75-v5-v8-0-282ff5d98dda@ambarella.com> In-Reply-To: <20260921-cv75-v5-v8-0-282ff5d98dda@ambarella.com> To: Arnd Bergmann , Krzysztof Kozlowski , Alexandre Belloni , soc@lists.linux.dev, linux-arm-kernel@lists.infradead.org Cc: Long Zhao , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Michael Turquette , Stephen Boyd , Jerome Brunet , Linus Walleij , Bartosz Golaszewski , Greg Kroah-Hartman , Jiri Slaby , Andy Shevchenko , =?utf-8?q?Ilpo_J=C3=A4rvinen?= , Catalin Marinas , Will Deacon , Long Zhao , Lee Jones , mfd@lists.linux.dev, devicetree@vger.kernel.org, linux-clk@vger.kernel.org, linux-gpio@vger.kernel.org, linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org X-Mailer: b4 0.15.2 X-Developer-Signature: v=1; a=ed25519-sha256; t=1789964608; l=3092; i=longzhao@ambarella.com; s=20260730; h=from:subject:message-id; bh=fpAj3vMXjZmURWyfts5CtyfyhTDoS5mn512oJA6h2aY=; b=e+MsuppDlgpjoNWogF4SShQN6eYtdesHSzDj+4r/pX+nVj5fmsfe+JIJpzHDyZ0LZ8NJ/XwPo I2z4VDEPGc2DvMHBbmioeZ8u/yVtTANgbGaSMPr/HFraoL+ryizimzx X-Developer-Key: i=longzhao@ambarella.com; a=ed25519; pk=/xGhPTOX0/eYsyTWzyjjgAIW1Z/YD+IlnOnvcdRozow= X-Endpoint-Received: by B4 Relay for longzhao@ambarella.com/20260730 with auth_id=903 X-Original-From: Long Zhao Reply-To: longzhao@ambarella.com From: Long Zhao Some controllers ignore data-register writes while a line is still an input. Optionally write the output value again after switching the direction, matching the existing PL061 behaviour. Signed-off-by: Long Zhao --- drivers/gpio/gpio-regmap.c | 19 +++++++++++++++++-- include/linux/gpio/regmap.h | 8 ++++++++ 2 files changed, 25 insertions(+), 2 deletions(-) diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c index 51b4d69b8740..fbd4c753525a 100644 --- a/drivers/gpio/gpio-regmap.c +++ b/drivers/gpio/gpio-regmap.c @@ -31,6 +31,7 @@ struct gpio_regmap { unsigned int reg_clr_base; unsigned int reg_dir_in_base; unsigned int reg_dir_out_base; + bool write_data_after_dir; unsigned long *fixed_direction_mask; unsigned long *fixed_direction_output; @@ -271,9 +272,21 @@ static int gpio_regmap_direction_output(struct gpio_chip *chip, return ret; } - gpio_regmap_set(chip, offset, value); + if (!gpio->write_data_after_dir) + gpio_regmap_set(chip, offset, value); - return gpio_regmap_set_direction(chip, offset, true); + ret = gpio_regmap_set_direction(chip, offset, true); + if (ret) + return ret; + + /* + * Some controllers ignore data-register writes while the line is + * still an input. Write the output value after switching direction. + */ + if (gpio->write_data_after_dir) + gpio_regmap_set(chip, offset, value); + + return 0; } void *gpio_regmap_get_drvdata(struct gpio_regmap *gpio) @@ -376,6 +389,8 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config config->fixed_direction_output, chip->ngpio); } + gpio->write_data_after_dir = config->write_data_after_dir; + /* if not set, assume there is only one register */ gpio->ngpio_per_reg = config->ngpio_per_reg; if (!gpio->ngpio_per_reg) diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h index 06255756710d..d7ffc12b00a2 100644 --- a/include/linux/gpio/regmap.h +++ b/include/linux/gpio/regmap.h @@ -48,6 +48,13 @@ struct regmap; * (Optional) Bitmap representing the fixed direction of * the GPIO lines. Useful when there are GPIO lines with a * fixed direction mixed together in the same register. + * @write_data_after_dir: + * (Optional) Write the output value again after + * switching a line to output in ->direction_output(). + * Needed for hardware which ignores data register + * writes while the line is configured as an input. + * This is a legacy quirk (e.g. ARM PL061); new hardware + * must not use it. Direction changes will glitch. * @drvdata: (Optional) Pointer to driver specific data which is * not used by gpio-remap but is provided "as is" to the * driver callback(s). @@ -94,6 +101,7 @@ struct gpio_regmap_config { unsigned int reg_dir_out_base; int reg_stride; int ngpio_per_reg; + bool write_data_after_dir; struct irq_domain *irq_domain; unsigned long *fixed_direction_mask; unsigned long *fixed_direction_output; -- 2.34.1