From patchwork Wed Feb 14 16:24:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Th=C3=A9o_Lebrun?= X-Patchwork-Id: 13556738 Received: from relay3-d.mail.gandi.net (relay3-d.mail.gandi.net [217.70.183.195]) (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 8216C6088E; Wed, 14 Feb 2024 16:24:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.195 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707927901; cv=none; b=eh8PtnHn1BPeC3Fe8qIsxr1MbG/wMY8k5vyUxpbQhiExD5+JhcsgJ9T0tw1YJtfvFa35q4NfejyAI5h/r2haGuyei4jgDFNutNo2pEbAbV/hoPy1aGvZ8YLJFnNIQQ1Nhws2BRoX9ZgwSFLCDCMzsHt1VgX0sAyYQqGf0guuHoY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707927901; c=relaxed/simple; bh=Dq+giMSUiMzlo14BqRxYrVJPYX/xUeMg7SlukALOVs8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ozgzKYCPk+Ekd/OJe5Hhe1mOjiEIl3ZOncNf3kzKUte9zShKFloRz6FTwJHlcXbVXZruMMIcYIJc5uiHYdZV330SbEbpxb58DUV4fcnA0dzg0nCoOW7aApOfcIlXYEAmnX/M68wIymQGEuH/XSg4joXIZQhiXzlO0mHXl2oEsec= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=mCxe5QlQ; arc=none smtp.client-ip=217.70.183.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="mCxe5QlQ" Received: by mail.gandi.net (Postfix) with ESMTPSA id E806860005; Wed, 14 Feb 2024 16:24:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1707927896; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=NCaDRLYX6xBK4eyROrBs4lVh6WU3g4rBScYkTurdSWQ=; b=mCxe5QlQ1CXL3R/VEcTEcrDDKJ45tWeH1dLQWwLBZquhcJp5kevwlZJYZe52ad1kBS1MfN GNJa+X4fuRxTWvUa8avI7ZbBz9MQ6zIO1XzBH7qOY1gSlpd8qvnQqtMe3heeyXUceOrrP8 Mz0UEQaC2oM9SXp4j2pZ3dE7aOngHFyqkst28vERPlgAEyKzRWEXmJB2bosvfhTdLs8lLu ZQDZ717HQvMECJ8TCGvRg3T/WS75/YTP1u/grxJkfjVqODzcAf4pYKy7j3B7J88/P32dHJ etJ8HyzzA4TKvHVlDQKBrQq1BgJ4C/u5v6HWf/F+UafmeU851Yg7HwE/lRZKzw== From: =?utf-8?q?Th=C3=A9o_Lebrun?= Date: Wed, 14 Feb 2024 17:24:09 +0100 Subject: [PATCH 16/23] gpio: nomadik: support shared GPIO IRQs Precedence: bulk X-Mailing-List: linux-mips@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240214-mbly-gpio-v1-16-f88c0ccf372b@bootlin.com> References: <20240214-mbly-gpio-v1-0-f88c0ccf372b@bootlin.com> In-Reply-To: <20240214-mbly-gpio-v1-0-f88c0ccf372b@bootlin.com> To: Linus Walleij , Bartosz Golaszewski , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Philipp Zabel , Thomas Bogendoerfer Cc: linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, Gregory CLEMENT , Vladimir Kondratiev , Thomas Petazzoni , Tawfik Bayouk , =?utf-8?q?Th=C3=A9o_Lebrun?= X-Mailer: b4 0.12.4 X-GND-Sasl: theo.lebrun@bootlin.com Support a single IRQs used by multiple GPIO banks. Change the IRQ handler type from a chained handler (as used by gpiolib for ->parent_handler) to a threaded IRQ. Use a fake raw spinlock to ensure generic_handle_irq() is called in a no-irq context. See Documentation/driver-api/gpio/driver.rst, "CHAINED CASCADED GPIO IRQCHIPS" for additional information. The Mobileye EyeQ5 platform uses this GPIO controller and share an IRQ for its two banks. Signed-off-by: Théo Lebrun --- drivers/gpio/gpio-nomadik.c | 67 +++++++++++++++++++++------------------ include/linux/gpio/gpio-nomadik.h | 1 + 2 files changed, 38 insertions(+), 30 deletions(-) diff --git a/drivers/gpio/gpio-nomadik.c b/drivers/gpio/gpio-nomadik.c index 25c8490aa1b6..5b1e3b3efcff 100644 --- a/drivers/gpio/gpio-nomadik.c +++ b/drivers/gpio/gpio-nomadik.c @@ -254,27 +254,31 @@ static void nmk_gpio_irq_shutdown(struct irq_data *d) clk_disable(nmk_chip->clk); } -static void nmk_gpio_irq_handler(struct irq_desc *desc) +static irqreturn_t nmk_gpio_irq_handler(int irq, void *dev_id) { - struct irq_chip *host_chip = irq_desc_get_chip(desc); - struct gpio_chip *chip = irq_desc_get_handler_data(desc); - struct nmk_gpio_chip *nmk_chip = gpiochip_get_data(chip); - u32 status; - - chained_irq_enter(host_chip, desc); + struct nmk_gpio_chip *nmk_chip = dev_id; + struct gpio_chip *chip = &nmk_chip->chip; + unsigned long mask = GENMASK(chip->ngpio - 1, 0); + unsigned long flags, status; + int bit; clk_enable(nmk_chip->clk); + status = readl(nmk_chip->addr + NMK_GPIO_IS); - clk_disable(nmk_chip->clk); - while (status) { - int bit = __ffs(status); + /* Ensure we cannot leave pending bits; this should never occur. */ + if (unlikely(status & ~mask)) + writel(status & ~mask, nmk_chip->addr + NMK_GPIO_IC); + + clk_disable(nmk_chip->clk); + for_each_set_bit(bit, &status, chip->ngpio) { + raw_spin_lock_irqsave(&nmk_chip->fake_lock, flags); generic_handle_domain_irq(chip->irq.domain, bit); - status &= ~BIT(bit); + raw_spin_unlock_irqrestore(&nmk_chip->fake_lock, flags); } - chained_irq_exit(host_chip, desc); + return IRQ_RETVAL((status & mask) != 0); } /* I/O Functions */ @@ -566,19 +570,20 @@ static const struct irq_chip nmk_irq_chip = { GPIOCHIP_IRQ_RESOURCE_HELPERS, }; -static int nmk_gpio_probe(struct platform_device *dev) +static int nmk_gpio_probe(struct platform_device *pdev) { - struct device_node *np = dev->dev.of_node; + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; struct nmk_gpio_chip *nmk_chip; - struct gpio_chip *chip; struct gpio_irq_chip *girq; bool supports_sleepmode; + struct gpio_chip *chip; int irq; int ret; - nmk_chip = nmk_gpio_populate_chip(np, dev); + nmk_chip = nmk_gpio_populate_chip(np, pdev); if (IS_ERR(nmk_chip)) { - dev_err(&dev->dev, "could not populate nmk chip struct\n"); + dev_err(dev, "could not populate nmk chip struct\n"); return PTR_ERR(nmk_chip); } @@ -586,9 +591,9 @@ static int nmk_gpio_probe(struct platform_device *dev) of_property_read_bool(np, "st,supports-sleepmode"); /* Correct platform device ID */ - dev->id = nmk_chip->bank; + pdev->id = nmk_chip->bank; - irq = platform_get_irq(dev, 0); + irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; @@ -600,7 +605,7 @@ static int nmk_gpio_probe(struct platform_device *dev) spin_lock_init(&nmk_chip->lock); chip = &nmk_chip->chip; - chip->parent = &dev->dev; + chip->parent = dev; chip->request = gpiochip_generic_request; chip->free = gpiochip_generic_free; chip->get_direction = nmk_gpio_get_dir; @@ -614,17 +619,19 @@ static int nmk_gpio_probe(struct platform_device *dev) girq = &chip->irq; gpio_irq_chip_set_chip(girq, &nmk_irq_chip); - girq->parent_handler = nmk_gpio_irq_handler; - girq->num_parents = 1; - girq->parents = devm_kcalloc(&dev->dev, 1, - sizeof(*girq->parents), - GFP_KERNEL); - if (!girq->parents) - return -ENOMEM; - girq->parents[0] = irq; + girq->parent_handler = NULL; + girq->num_parents = 0; + girq->parents = NULL; girq->default_type = IRQ_TYPE_NONE; girq->handler = handle_edge_irq; + ret = devm_request_irq(dev, irq, nmk_gpio_irq_handler, IRQF_SHARED, + dev_name(dev), nmk_chip); + if (ret) { + dev_err(dev, "failed requesting IRQ\n"); + return ret; + } + clk_enable(nmk_chip->clk); nmk_chip->lowemi = readl_relaxed(nmk_chip->addr + NMK_GPIO_LOWEMI); clk_disable(nmk_chip->clk); @@ -633,9 +640,9 @@ static int nmk_gpio_probe(struct platform_device *dev) if (ret) return ret; - platform_set_drvdata(dev, nmk_chip); + platform_set_drvdata(pdev, nmk_chip); - dev_info(&dev->dev, "chip registered\n"); + dev_info(dev, "chip registered\n"); return 0; } diff --git a/include/linux/gpio/gpio-nomadik.h b/include/linux/gpio/gpio-nomadik.h index 0166ddb71f43..8f7bb756ad35 100644 --- a/include/linux/gpio/gpio-nomadik.h +++ b/include/linux/gpio/gpio-nomadik.h @@ -56,6 +56,7 @@ struct nmk_gpio_chip { unsigned int bank; void (*set_ioforce)(bool enable); spinlock_t lock; + raw_spinlock_t fake_lock; bool sleepmode; /* Keep track of configured edges */ u32 edge_rising;