From patchwork Thu May 15 06:21:18 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Peter via B4 Relay X-Patchwork-Id: 890522 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 07E1F296D2C; Thu, 15 May 2025 06:22:15 +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=1747290135; cv=none; b=RdunslMm4fIDNIHxKW+XrRyTlYJKb0bS6lCCsPo6+hPTaAUZj42k6a+qcGJu+4BRlThm4UBT/J5/Mw354n0yd0L42GvCA3K+FQ+N1LV57W22muXEldJp3O7Up9G8EEsBQpbnm6JaSC95o236imYD00qOCD3/WQ2SSdQnYdihVMM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747290135; c=relaxed/simple; bh=30ZD5Z2cB4b1Mg2SYua2SNUON9SvIrxzWTdu7USDv5M=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=SC31RnpOTYYkB/UHSGlLLRmPa9w009HTPX4MMAHjrcxYuYeODin00iHX4cWc9P7KlBRqGVso2rp9baoBuy4NogjUbVKFgHVHYohsAV9XM3N0rOnxTlJPHYVi1M7nhEYYKtfMgV0Fia9sx/G59IHtvAMIkmfox7gzHybXXOtGfo4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QloEdcL2; 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="QloEdcL2" Received: by smtp.kernel.org (Postfix) with ESMTPS id 8062CC4CEFD; Thu, 15 May 2025 06:22:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1747290134; bh=30ZD5Z2cB4b1Mg2SYua2SNUON9SvIrxzWTdu7USDv5M=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=QloEdcL2sr3pVO+FEOrTGz5Eyr0m90F1ofXFyI68TEoyrHzevwOkqfD9ZkejLVNs8 rJN2DYUvMFp2wDJwTeooFU+vLwBDaQ4ZUuX9r4RF9MlEzz5+CbLN9gKAZKOBF0kPXp v8uaDK3mIpOEOBJJZCn8OZBuPAwmwiDdvCkAb7ENUpw/a/Ga7h8QoVPT+zbkLp0qrP 3FRwX6l+UDtFNNhzJw8+04ff0rfGVgymDsCjouB9aTDBc0jUo2G8y6RLw+Lr4B6vNC 7y6N4ljGCiwEjE1pXW8JNk+gCIOBwf5JiD6w/1NchoWURVqzxJkkFmK0um+vzUp31e DNPPW7a0pKWDw== 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 76967C3DA6D; Thu, 15 May 2025 06:22:14 +0000 (UTC) From: Sven Peter via B4 Relay Date: Thu, 15 May 2025 06:21:18 +0000 Subject: [PATCH v6 06/10] gpio: Add new gpio-macsmc driver for Apple Macs Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250515-smc-6-15-v6-6-c47b1ef4b0ae@svenpeter.dev> References: <20250515-smc-6-15-v6-0-c47b1ef4b0ae@svenpeter.dev> In-Reply-To: <20250515-smc-6-15-v6-0-c47b1ef4b0ae@svenpeter.dev> To: Sven Peter , Janne Grunau , Alyssa Rosenzweig , Neal Gompa , Hector Martin , Linus Walleij , Bartosz Golaszewski , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Sebastian Reichel , Lee Jones , Marc Zyngier , "Russell King (Oracle)" Cc: asahi@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=10960; i=sven@svenpeter.dev; h=from:subject:message-id; bh=nRIP2lbfi8Qx2314ng3IAUeq0fIP5UD1ZzN8EKd2EkE=; b=owGbwMvMwCHmIlirolUq95LxtFoSQ4ZqB29yDctus0WCc/J5b23YcvLn1gfx1ZaRr2u/Pt96v /xV+M0THaUsDGIcDLJiiizb99ubPnn4RnDppkvvYeawMoEMYeDiFICJPFJgZHgsfDbysqecjaKK jNtTj9TTV/f0vLGeeOv0yisdyeEanTsZ/lfM/VLm9rOVQeWyZ0qK7tcr6+8l9AUzXlC0eRQUJ+G bzwsA X-Developer-Key: i=sven@svenpeter.dev; a=openpgp; fpr=A1E3E34A2B3C820DBC4955E5993B08092F131F93 X-Endpoint-Received: by B4 Relay for sven@svenpeter.dev/default with auth_id=167 X-Original-From: Sven Peter Reply-To: sven@svenpeter.dev From: Hector Martin This driver implements the GPIO service on top of the SMC framework on Apple Mac machines. In particular, these are the GPIOs present in the PMU IC which are used to control power to certain on-board devices. Although the underlying hardware supports various pin config settings (input/output, open drain, etc.), this driver does not implement that functionality and leaves it up to the firmware to configure things properly. We also don't yet support interrupts/events. This is sufficient for device power control, which is the only thing we need to support at this point. More features will be implemented when needed. To our knowledge, only Apple Silicon Macs implement this SMC feature. Signed-off-by: Hector Martin Reviewed-by: Bartosz Golaszewski Reviewed-by: Linus Walleij Reviewed-by: Sven Peter Signed-off-by: Russell King (Oracle) Reviewed-by: Alyssa Rosenzweig Reviewed-by: Neal Gompa Signed-off-by: Sven Peter --- MAINTAINERS | 1 + drivers/gpio/Kconfig | 10 ++ drivers/gpio/Makefile | 1 + drivers/gpio/gpio-macsmc.c | 292 +++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 304 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index dfaca531600c22d487fb17a25294686611dd4513..fa3a5f9ee40446bcc725c9eac2a36651e6bc7553 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2291,6 +2291,7 @@ F: drivers/bluetooth/hci_bcm4377.c F: drivers/clk/clk-apple-nco.c F: drivers/cpufreq/apple-soc-cpufreq.c F: drivers/dma/apple-admac.c +F: drivers/gpio/gpio-macsmc.c F: drivers/pmdomain/apple/ F: drivers/i2c/busses/i2c-pasemi-core.c F: drivers/i2c/busses/i2c-pasemi-platform.c diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index f2c39bbff83a33dcb12b2d32aa3ebc358a0dd949..f0e25105f8ebe7356344722987333a9fc244ea1f 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -1440,6 +1440,16 @@ config GPIO_LP87565 This driver can also be built as a module. If so, the module will be called gpio-lp87565. +config GPIO_MACSMC + tristate "Apple Mac SMC GPIO" + depends on MFD_MACSMC + help + Support for GPIOs controlled by the SMC microcontroller on Apple Mac + systems. + + This driver can also be built as a module. If so, the module will be + called gpio-macsmc. + config GPIO_MADERA tristate "Cirrus Logic Madera class codecs" depends on PINCTRL_MADERA diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index af130882ffeeef8b1d518867bfe1493ec4f21b5f..c2e47f356bfae73384ace8103074f246e49fb9d6 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -97,6 +97,7 @@ obj-$(CONFIG_GPIO_LP873X) += gpio-lp873x.o obj-$(CONFIG_GPIO_LP87565) += gpio-lp87565.o obj-$(CONFIG_GPIO_LPC18XX) += gpio-lpc18xx.o obj-$(CONFIG_GPIO_LPC32XX) += gpio-lpc32xx.o +obj-$(CONFIG_GPIO_MACSMC) += gpio-macsmc.o obj-$(CONFIG_GPIO_MADERA) += gpio-madera.o obj-$(CONFIG_GPIO_MAX3191X) += gpio-max3191x.o obj-$(CONFIG_GPIO_MAX7300) += gpio-max7300.o diff --git a/drivers/gpio/gpio-macsmc.c b/drivers/gpio/gpio-macsmc.c new file mode 100644 index 0000000000000000000000000000000000000000..7570d9e89adfff49b9858c82bb34b075fb0e5f16 --- /dev/null +++ b/drivers/gpio/gpio-macsmc.c @@ -0,0 +1,292 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple SMC GPIO driver + * Copyright The Asahi Linux Contributors + * + * This driver implements basic SMC PMU GPIO support that can read inputs + * and write outputs. Mode changes and IRQ config are not yet implemented. + */ + +#include +#include +#include +#include +#include + +#define MAX_GPIO 64 + +/* + * Commands 0-6 are, presumably, the intended API. + * Command 0xff lets you get/set the pin configuration in detail directly, + * but the bit meanings seem not to be stable between devices/PMU hardware + * versions. + * + * We're going to try to make do with the low commands for now. + * We don't implement pin mode changes at this time. + */ + +#define CMD_ACTION (0 << 24) +#define CMD_OUTPUT (1 << 24) +#define CMD_INPUT (2 << 24) +#define CMD_PINMODE (3 << 24) +#define CMD_IRQ_ENABLE (4 << 24) +#define CMD_IRQ_ACK (5 << 24) +#define CMD_IRQ_MODE (6 << 24) +#define CMD_CONFIG (0xff << 24) + +#define MODE_INPUT 0 +#define MODE_OUTPUT 1 +#define MODE_VALUE_0 0 +#define MODE_VALUE_1 2 + +#define IRQ_MODE_HIGH 0 +#define IRQ_MODE_LOW 1 +#define IRQ_MODE_RISING 2 +#define IRQ_MODE_FALLING 3 +#define IRQ_MODE_BOTH 4 + +#define CONFIG_MASK GENMASK(23, 16) +#define CONFIG_VAL GENMASK(7, 0) + +#define CONFIG_OUTMODE GENMASK(7, 6) +#define CONFIG_IRQMODE GENMASK(5, 3) +#define CONFIG_PULLDOWN BIT(2) +#define CONFIG_PULLUP BIT(1) +#define CONFIG_OUTVAL BIT(0) + +/* + * Output modes seem to differ depending on the PMU in use... ? + * j274 / M1 (Sera PMU): + * 0 = input + * 1 = output + * 2 = open drain + * 3 = disable + * j314 / M1Pro (Maverick PMU): + * 0 = input + * 1 = open drain + * 2 = output + * 3 = ? + */ + +struct macsmc_gpio { + struct device *dev; + struct apple_smc *smc; + struct gpio_chip gc; + + int first_index; +}; + +static int macsmc_gpio_nr(smc_key key) +{ + int low = hex_to_bin(key & 0xff); + int high = hex_to_bin((key >> 8) & 0xff); + + if (low < 0 || high < 0) + return -1; + + return low | (high << 4); +} + +static int macsmc_gpio_key(unsigned int offset) +{ + return _SMC_KEY("gP\0\0") | hex_asc_hi(offset) << 8 | hex_asc_lo(offset); +} + +static int macsmc_gpio_find_first_gpio_index(struct macsmc_gpio *smcgp) +{ + struct apple_smc *smc = smcgp->smc; + smc_key key = macsmc_gpio_key(0); + smc_key first_key, last_key; + int start, count, ret; + + /* Return early if the key is out of bounds */ + ret = apple_smc_get_key_by_index(smc, 0, &first_key); + if (ret) + return ret; + if (key <= first_key) + return -ENODEV; + + ret = apple_smc_get_key_by_index(smc, smc->key_count - 1, &last_key); + if (ret) + return ret; + if (key > last_key) + return -ENODEV; + + /* Binary search to find index of first SMC key bigger or equal to key */ + start = 0; + count = smc->key_count; + while (count > 1) { + smc_key pkey; + int pivot = start + ((count - 1) >> 1); + + ret = apple_smc_get_key_by_index(smc, pivot, &pkey); + if (ret < 0) + return ret; + + if (pkey == key) + return pivot; + + pivot++; + + if (pkey < key) { + count -= pivot - start; + start = pivot; + } else { + count = pivot - start; + } + } + + return start; +} + +static int macsmc_gpio_get_direction(struct gpio_chip *gc, unsigned int offset) +{ + struct macsmc_gpio *smcgp = gpiochip_get_data(gc); + smc_key key = macsmc_gpio_key(offset); + u32 val; + int ret; + + /* First try reading the explicit pin mode register */ + ret = apple_smc_rw_u32(smcgp->smc, key, CMD_PINMODE, &val); + if (!ret) + return (val & MODE_OUTPUT) ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN; + + /* + * Less common IRQ configs cause CMD_PINMODE to fail, and so does open drain mode. + * Fall back to reading IRQ mode, which will only succeed for inputs. + */ + ret = apple_smc_rw_u32(smcgp->smc, key, CMD_IRQ_MODE, &val); + return ret ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN; +} + +static int macsmc_gpio_get(struct gpio_chip *gc, unsigned int offset) +{ + struct macsmc_gpio *smcgp = gpiochip_get_data(gc); + smc_key key = macsmc_gpio_key(offset); + u32 cmd, val; + int ret; + + ret = macsmc_gpio_get_direction(gc, offset); + if (ret < 0) + return ret; + + if (ret == GPIO_LINE_DIRECTION_OUT) + cmd = CMD_OUTPUT; + else + cmd = CMD_INPUT; + + ret = apple_smc_rw_u32(smcgp->smc, key, cmd, &val); + if (ret < 0) + return ret; + + return val ? 1 : 0; +} + +static int macsmc_gpio_set(struct gpio_chip *gc, unsigned int offset, int value) +{ + struct macsmc_gpio *smcgp = gpiochip_get_data(gc); + smc_key key = macsmc_gpio_key(offset); + int ret; + + value |= CMD_OUTPUT; + ret = apple_smc_write_u32(smcgp->smc, key, CMD_OUTPUT | value); + if (ret < 0) + dev_err(smcgp->dev, "GPIO set failed %p4ch = 0x%x\n", + &key, value); + + return ret; +} + +static int macsmc_gpio_init_valid_mask(struct gpio_chip *gc, + unsigned long *valid_mask, unsigned int ngpios) +{ + struct macsmc_gpio *smcgp = gpiochip_get_data(gc); + int count; + int i; + + count = min(smcgp->smc->key_count, MAX_GPIO); + + bitmap_zero(valid_mask, ngpios); + + for (i = 0; i < count; i++) { + int ret, gpio_nr; + smc_key key; + + ret = apple_smc_get_key_by_index(smcgp->smc, smcgp->first_index + i, &key); + if (ret < 0) + return ret; + + if (key > SMC_KEY(gPff)) + break; + + gpio_nr = macsmc_gpio_nr(key); + if (gpio_nr < 0 || gpio_nr > MAX_GPIO) { + dev_err(smcgp->dev, "Bad GPIO key %p4ch\n", &key); + continue; + } + + set_bit(gpio_nr, valid_mask); + } + + return 0; +} + +static int macsmc_gpio_probe(struct platform_device *pdev) +{ + struct macsmc_gpio *smcgp; + struct apple_smc *smc = dev_get_drvdata(pdev->dev.parent); + smc_key key; + int ret; + + smcgp = devm_kzalloc(&pdev->dev, sizeof(*smcgp), GFP_KERNEL); + if (!smcgp) + return -ENOMEM; + + smcgp->dev = &pdev->dev; + smcgp->smc = smc; + + smcgp->first_index = macsmc_gpio_find_first_gpio_index(smcgp); + if (smcgp->first_index < 0) + return smcgp->first_index; + + ret = apple_smc_get_key_by_index(smc, smcgp->first_index, &key); + if (ret < 0) + return ret; + + if (key > macsmc_gpio_key(MAX_GPIO - 1)) + return -ENODEV; + + dev_info(smcgp->dev, "First GPIO key: %p4ch\n", &key); + + smcgp->gc.label = "macsmc-pmu-gpio"; + smcgp->gc.owner = THIS_MODULE; + smcgp->gc.get = macsmc_gpio_get; + smcgp->gc.set_rv = macsmc_gpio_set; + smcgp->gc.get_direction = macsmc_gpio_get_direction; + smcgp->gc.init_valid_mask = macsmc_gpio_init_valid_mask; + smcgp->gc.can_sleep = true; + smcgp->gc.ngpio = MAX_GPIO; + smcgp->gc.base = -1; + smcgp->gc.parent = &pdev->dev; + + return devm_gpiochip_add_data(&pdev->dev, &smcgp->gc, smcgp); +} + +static const struct of_device_id macsmc_gpio_of_table[] = { + { .compatible = "apple,smc-gpio", }, + {} +}; +MODULE_DEVICE_TABLE(of, macsmc_gpio_of_table); + +static struct platform_driver macsmc_gpio_driver = { + .driver = { + .name = "macsmc-gpio", + .of_match_table = macsmc_gpio_of_table, + }, + .probe = macsmc_gpio_probe, +}; +module_platform_driver(macsmc_gpio_driver); + +MODULE_AUTHOR("Hector Martin "); +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_DESCRIPTION("Apple SMC GPIO driver");