From patchwork Tue Nov 8 16:33:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Russell King (Oracle)" X-Patchwork-Id: 1701375 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=2620:137:e000::1:20; helo=out1.vger.email; envelope-from=linux-gpio-owner@vger.kernel.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.a=rsa-sha256 header.s=pandora-2019 header.b=zSRN7jM4; dkim-atps=neutral Received: from out1.vger.email (out1.vger.email [IPv6:2620:137:e000::1:20]) by legolas.ozlabs.org (Postfix) with ESMTP id 4N6DFH5MKxz1yqS for ; Wed, 9 Nov 2022 03:33:55 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234218AbiKHQdy (ORCPT ); Tue, 8 Nov 2022 11:33:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58720 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233654AbiKHQdx (ORCPT ); Tue, 8 Nov 2022 11:33:53 -0500 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6960357B45; Tue, 8 Nov 2022 08:33:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Date:Sender:Message-Id:Content-Type: Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References: In-Reply-To:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=0YuT/1kkHJsdBfN/BGMqpUuaH3DBVYf6Kah8+7mSTP0=; b=zSRN7jM4d9Lez4dLQdLNSCChFn gvXBWsZDj7VDAWF7OVrUrSrlsDcCpQvKvJeTFFCvrzTKytGBmnOsqHnkpZfjgGMZqfYYJDl5RJKNv xq9tFz3wdy7ZQeqNek/Avy2ErToMa1GEf8td2P/9KAu8mztJW3He4S6O3+bObLUSB38ilJiNbbuhz LvCw7Sj+dC+1LrJwv8s+Wxtezuvwc+peXoxkgzO35f2vdOTnDx240BFR+JfRkXxcGWWL2pmXsTWVD PEsgfiSNJlbVDU30cBX6suit1nUohBix3iHEcjZbvxowkBor8b+gSSLGW/XFoKYeVeRF29FVqzOqD gjTXczFg==; Received: from e0022681537dd.dyn.armlinux.org.uk ([fd8f:7570:feb6:1:222:68ff:fe15:37dd]:40942 helo=rmk-PC.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1osRXo-0003Ta-Lt; Tue, 08 Nov 2022 16:33:48 +0000 Received: from rmk by rmk-PC.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1osRXo-002mwR-1T; Tue, 08 Nov 2022 16:33:48 +0000 In-Reply-To: References: From: Russell King (Oracle) To: Linus Walleij , Bartosz Golaszewski , Rob Herring , Lee Jones Cc: Alyssa Rosenzweig , Andy Shevchenko , asahi@lists.linux.dev, devicetree@vger.kernel.org, Hector Martin , Jonathan Corbet , Krzysztof Kozlowski , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-gpio@vger.kernel.org, Petr Mladek , Rasmus Villemoes , Sergey Senozhatsky , Steven Rostedt , Sven Peter Subject: [PATCH v3 7/7] gpio: Add new gpio-macsmc driver for Apple Macs MIME-Version: 1.0 Content-Disposition: inline Message-Id: Sender: Russell King Date: Tue, 08 Nov 2022 16:33:48 +0000 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org 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) --- drivers/gpio/Kconfig | 11 ++ drivers/gpio/Makefile | 1 + drivers/gpio/gpio-macsmc.c | 245 +++++++++++++++++++++++++++++++++++++ 3 files changed, 257 insertions(+) create mode 100644 drivers/gpio/gpio-macsmc.c diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig index a01af1180616..08138322010a 100644 --- a/drivers/gpio/Kconfig +++ b/drivers/gpio/Kconfig @@ -1283,6 +1283,17 @@ 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 + default ARCH_APPLE + 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 29e3beb6548c..467833cc9a9d 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -83,6 +83,7 @@ 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 000000000000..24ec98ad18f7 --- /dev/null +++ b/drivers/gpio/gpio-macsmc.c @@ -0,0 +1,245 @@ +// 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_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 void 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); +} + +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 = apple_smc_get_key_count(smcgp->smc) - smcgp->first_index; + if (count > MAX_GPIO) + 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 = apple_smc_find_first_key_index(smc, SMC_KEY(gP00)); + + if (smcgp->first_index >= apple_smc_get_key_count(smc)) + return -ENODEV; + + 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 = 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"); +MODULE_ALIAS("platform:macsmc-gpio");