From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from stravinsky.debian.org (stravinsky.debian.org [82.195.75.108]) (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 C433C36F8E6; Wed, 30 Sep 2026 16:07:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.195.75.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790784433; cv=none; b=XXpKk754NtTAWusKwYrbtJNHZ5E1mQidmhmASlVVPMlgFFVNg+DDq9uh28Md7gJDkt2VYfNen4/XQng0PvM2+cHhxT/FrvQO88s9XnCMCeI0fhrOh9KI9GN93ut/AqHNCJ7VsK3D/vAGlOAXTcin5u6JoKztuy9HhEBs1yPqcUQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790784433; c=relaxed/simple; bh=f3bGz4vJvRVmKwqlOkVDrITA8jXzvYc1Adch/QVRN7I=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=LUmi2xK6i5a6IsYUXXyEqERXvG3qML+cscxQWkV8PF7vEserzv/jdaT+6ZFFteNRPuXX18ywK2NIqwODILXDTTV06nNEkS0nL1LzLaeDwG/SJk41KzmTOGpaVfNuGCKgT4IY71KbPwA0bmAaCB1yCr3593gSbp2I/ftDq9qasDc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org; spf=pass smtp.mailfrom=debian.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b=ICn4PPhg; arc=none smtp.client-ip=82.195.75.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=debian.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b="ICn4PPhg" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:Content-Transfer-Encoding:Content-Type :MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-ID:Content-Description; bh=QVdJoTZrf5oVRzxuzEqtk4rKJA30YOVUw7GNyyn3X8o=; b=ICn4PPhgtTJvtdEKkmvnxcurZ6 UXWsLiIdxjmkfaapz4YtRL7tLYHhbd8rW/XVsn46y4Xi/qJ76QTMLOLoQpYIHgISZYQM+yqNTcct3 RLYq07+Z7CQ7gdjisfzECdVnpfewcrkM7qTuYWm5M/X3yWRQp2CuENOffvU4W28+xE0BfZ6Iy2xld QXG/ZgvS28dzawzAziMIssKmDSBGyeIaOcrhTalW/lA45iU+4aitlj1HzPFEmc6JfgDLSADLcOmUu +ajzMK1AI9eCeRnvWeu1ezxWS70mPeZlozpN9TkMy9EdG8ddnsBEn6oE+4OzL4PCLk7ZaEJdzvmZs MoclClPA==; Received: from authenticated-user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.96) (envelope-from ) id 1xBwpa-009IoV-0U; Wed, 30 Sep 2026 16:06:54 +0000 From: Shih-Yuan Lee To: Mark Brown Cc: Andy Shevchenko , Mika Westerberg , Lukas Wunner , Daniel Mack , Haojian Zhuang , Robert Jarzmik , linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Shih-Yuan Lee Subject: [PATCH v17 2/6] spi: pxa2xx: introduce clock enable and disable helper functions Date: Thu, 1 Oct 2026 00:06:25 +0800 Message-Id: <20260930160629.1822-3-fourdollars@debian.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20260930160629.1822-1-fourdollars@debian.org> References: <20260930160629.1822-1-fourdollars@debian.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Debian-User: fourdollars The driver enables and disables the SOC clock during probe, teardown, and power management callbacks. Directly calling clk_disable_unprepare() when the clock is already disabled—such as when removing a device that is runtime-suspended—causes an unbalanced clock disable warning from the Common Clock Framework. Introduce pxa2xx_spi_clk_enable() and pxa2xx_spi_clk_disable() helper functions that track the clock state with a 'clk_enabled' boolean flag protected by a 'clk_lock' mutex in struct driver_data. These helpers make clock toggling idempotent: repeated enable or disable invocations are safe no-ops serialized by clk_lock. Convert probe, remove, suspend, resume, and runtime PM callbacks to use these helpers instead of direct clk_prepare_enable() and clk_disable_unprepare() calls. Pack 'clk_enabled' immediately after 'n_bytes' into the existing padding hole in struct driver_data, avoiding additional alignment padding. Assisted-by: Antigravity:gemini-3.8-flash sparse Signed-off-by: Shih-Yuan Lee --- drivers/spi/spi-pxa2xx.c | 41 ++++++++++++++++++++++++++++++++-------- drivers/spi/spi-pxa2xx.h | 2 ++ 2 files changed, 35 insertions(+), 8 deletions(-) diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c index b11e30589074..a9d19d9a5343 100644 --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -713,6 +713,31 @@ static void handle_bad_msg(struct driver_data *drv_data) dev_err(drv_data->ssp->dev, "bad message state in interrupt handler\n"); } +static int pxa2xx_spi_clk_enable(struct driver_data *drv_data) +{ + int ret = 0; + + mutex_lock(&drv_data->clk_lock); + if (!drv_data->clk_enabled) { + ret = clk_prepare_enable(drv_data->ssp->clk); + if (!ret) + drv_data->clk_enabled = true; + } + mutex_unlock(&drv_data->clk_lock); + + return ret; +} + +static void pxa2xx_spi_clk_disable(struct driver_data *drv_data) +{ + mutex_lock(&drv_data->clk_lock); + if (drv_data->clk_enabled) { + drv_data->clk_enabled = false; + clk_disable_unprepare(drv_data->ssp->clk); + } + mutex_unlock(&drv_data->clk_lock); +} + static irqreturn_t ssp_int(int irq, void *dev_id) { struct driver_data *drv_data = dev_id; @@ -1288,6 +1313,7 @@ int pxa2xx_spi_probe(struct device *dev, struct ssp_device *ssp, drv_data->controller = controller; drv_data->controller_info = platform_info; drv_data->ssp = ssp; + mutex_init(&drv_data->clk_lock); /* The spi->mode bits understood by this driver: */ controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP; @@ -1352,7 +1378,7 @@ int pxa2xx_spi_probe(struct device *dev, struct ssp_device *ssp, } /* Enable SOC clock */ - ret = clk_prepare_enable(ssp->clk); + ret = pxa2xx_spi_clk_enable(drv_data); if (ret) goto out_error_dma_irq_alloc; @@ -1449,7 +1475,7 @@ int pxa2xx_spi_probe(struct device *dev, struct ssp_device *ssp, return ret; out_error_clock_enabled: - clk_disable_unprepare(ssp->clk); + pxa2xx_spi_clk_disable(drv_data); out_error_dma_irq_alloc: pxa2xx_spi_dma_release(drv_data); @@ -1468,7 +1494,7 @@ void pxa2xx_spi_remove(struct device *dev) /* Disable the SSP at the peripheral and SOC level */ pxa_ssp_disable(ssp); - clk_disable_unprepare(ssp->clk); + pxa2xx_spi_clk_disable(drv_data); /* Release DMA */ if (drv_data->controller_info->enable_dma) @@ -1492,7 +1518,7 @@ static int pxa2xx_spi_suspend(struct device *dev) pxa_ssp_disable(ssp); if (!pm_runtime_suspended(dev)) - clk_disable_unprepare(ssp->clk); + pxa2xx_spi_clk_disable(drv_data); return 0; } @@ -1500,12 +1526,11 @@ static int pxa2xx_spi_suspend(struct device *dev) static int pxa2xx_spi_resume(struct device *dev) { struct driver_data *drv_data = dev_get_drvdata(dev); - struct ssp_device *ssp = drv_data->ssp; int ret; /* Enable the SSP clock */ if (!pm_runtime_suspended(dev)) { - ret = clk_prepare_enable(ssp->clk); + ret = pxa2xx_spi_clk_enable(drv_data); if (ret) return ret; } @@ -1518,7 +1543,7 @@ static int pxa2xx_spi_runtime_suspend(struct device *dev) { struct driver_data *drv_data = dev_get_drvdata(dev); - clk_disable_unprepare(drv_data->ssp->clk); + pxa2xx_spi_clk_disable(drv_data); return 0; } @@ -1526,7 +1551,7 @@ static int pxa2xx_spi_runtime_resume(struct device *dev) { struct driver_data *drv_data = dev_get_drvdata(dev); - return clk_prepare_enable(drv_data->ssp->clk); + return pxa2xx_spi_clk_enable(drv_data); } EXPORT_NS_GPL_DEV_PM_OPS(pxa2xx_spi_pm_ops, SPI_PXA2xx) = { diff --git a/drivers/spi/spi-pxa2xx.h b/drivers/spi/spi-pxa2xx.h index 447be0369384..3352239f74a0 100644 --- a/drivers/spi/spi-pxa2xx.h +++ b/drivers/spi/spi-pxa2xx.h @@ -66,6 +66,8 @@ struct driver_data { void *rx; void *rx_end; u8 n_bytes; + bool clk_enabled; + struct mutex clk_lock; int (*write)(struct driver_data *drv_data); int (*read)(struct driver_data *drv_data); irqreturn_t (*transfer_handler)(struct driver_data *drv_data); -- 2.39.5