From patchwork Mon Oct 30 20:50:00 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Timur Tabi X-Patchwork-Id: 10033129 X-Patchwork-Delegate: agross@codeaurora.org Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id DCC78600C5 for ; Mon, 30 Oct 2017 20:50:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CFCDD2896E for ; Mon, 30 Oct 2017 20:50:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C152628970; Mon, 30 Oct 2017 20:50:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5A98C28971 for ; Mon, 30 Oct 2017 20:50:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932490AbdJ3UuL (ORCPT ); Mon, 30 Oct 2017 16:50:11 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:44138 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932153AbdJ3UuK (ORCPT ); Mon, 30 Oct 2017 16:50:10 -0400 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id B7570607E8; Mon, 30 Oct 2017 20:50:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1509396609; bh=cDJ4gr2slX3EDntjeQ5sg8KEusyb+DRQh2D5l9SyDVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mxYiNLK/MQZ1FloG9CUsHnVixGklGQ2klCFX0qi994gxCas05c3lKXLgEOtu9WTUo UiMS7+j6hCRTBJGdgpnZNMDXpL4NmDtZVynWn/dS1H6OKYQ5rT5DKC1dvkLBGWUmWf ZZL8heAsGv+ZtBH/q3Zv4zAM26b6PZFX7r2Sfupw= Received: from timur-ubuntu.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: timur@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id D3CC7607C1; Mon, 30 Oct 2017 20:50:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1509396608; bh=cDJ4gr2slX3EDntjeQ5sg8KEusyb+DRQh2D5l9SyDVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EkJM8w1vOdodvvWuc3eNN2YsXk7g3LkdreJnh74Co5ucv743E9yeEOIAbJhOyIfhm Yxb5BnQnDrSEPLqUrtpUJd2C+ZdD8zk1ijyaNoBUjtpWTabAX6nIxJ/Znk3POUlvGQ 32ig59DUR0EiFmcEGp0PhJXg8zw4PshndL3lGcjM= DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org D3CC7607C1 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=timur@codeaurora.org From: Timur Tabi To: linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org, Linus Walleij , Andy Shevchenko , Mika Westerberg , thierry.reding@gmail.com, Stephen Boyd , david.brown@linaro.org, andy.gross@linaro.org, Bjorn Andersson Cc: timur@codeaurora.org Subject: [PATCH 2/4] gpiolib: add bitmask for valid GPIO lines Date: Mon, 30 Oct 2017 15:50:00 -0500 Message-Id: <1509396602-1936-3-git-send-email-timur@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1509396602-1936-1-git-send-email-timur@codeaurora.org> References: <1509396602-1936-1-git-send-email-timur@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add support for specifying that some GPIOs within a range are unavailable. Some systems have a sparse list of GPIOs, where a range of GPIOs is specified (usually 0 to n-1), but some subset within that range is absent or unavailable for whatever reason. To support this, allow drivers to specify a bitmask of GPIOs that are present or absent. Gpiolib will then block access to those that are absent. Signed-off-by: Timur Tabi --- drivers/gpio/gpiolib.c | 43 +++++++++++++++++++++++++++++++++++-------- include/linux/gpio/driver.h | 2 ++ 2 files changed, 37 insertions(+), 8 deletions(-) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 60553af4c004..c32387936cdd 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1481,22 +1481,36 @@ static struct gpio_chip *find_chip_by_name(const char *name) static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip) { - if (!gpiochip->irq_need_valid_mask) - return 0; + if (gpiochip->irq_need_valid_mask) { + gpiochip->irq_valid_mask = + kcalloc(BITS_TO_LONGS(gpiochip->ngpio), + sizeof(long), GFP_KERNEL); + if (!gpiochip->irq_valid_mask) + return -ENOMEM; - gpiochip->irq_valid_mask = kcalloc(BITS_TO_LONGS(gpiochip->ngpio), - sizeof(long), GFP_KERNEL); - if (!gpiochip->irq_valid_mask) - return -ENOMEM; + /* Assume by default all GPIOs are valid */ + bitmap_fill(gpiochip->irq_valid_mask, gpiochip->ngpio); + } - /* Assume by default all GPIOs are valid */ - bitmap_fill(gpiochip->irq_valid_mask, gpiochip->ngpio); + if (gpiochip->line_need_valid_mask) { + gpiochip->line_valid_mask = + kcalloc(BITS_TO_LONGS(gpiochip->ngpio), + sizeof(long), GFP_KERNEL); + if (!gpiochip->line_valid_mask) + return -ENOMEM; + + /* Assume by default all GPIOs are valid */ + bitmap_fill(gpiochip->line_valid_mask, gpiochip->ngpio); + } return 0; } static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip) { + kfree(gpiochip->line_valid_mask); + gpiochip->line_valid_mask = NULL; + kfree(gpiochip->irq_valid_mask); gpiochip->irq_valid_mask = NULL; } @@ -1510,6 +1524,15 @@ static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip, return test_bit(offset, gpiochip->irq_valid_mask); } +static bool gpiochip_irqchip_line_valid(const struct gpio_chip *gpiochip, + unsigned int offset) +{ + /* No mask means all valid */ + if (likely(!gpiochip->line_valid_mask)) + return true; + return test_bit(offset, gpiochip->line_valid_mask); +} + /** * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip * @gpiochip: the gpiochip to set the irqchip chain to @@ -3320,6 +3343,10 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev, return desc; } + /* Make sure the GPIO is valid before we request it. */ + if (!gpiochip_irqchip_line_valid(desc->gdev->chip, idx)) + return ERR_PTR(-EACCES); + status = gpiod_request(desc, con_id); if (status < 0) return ERR_PTR(status); diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index c97f8325e8bf..83df2934bdf7 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -172,6 +172,8 @@ struct gpio_chip { bool irq_nested; bool irq_need_valid_mask; unsigned long *irq_valid_mask; + bool line_need_valid_mask; + unsigned long *line_valid_mask; struct lock_class_key *lock_key; #endif