From patchwork Fri Mar 22 15:10:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Martin_T=C5=AFma?= X-Patchwork-Id: 781981 Received: from mx.gpxsee.org (mx.gpxsee.org [37.205.14.76]) by smtp.subspace.kernel.org (Postfix) with ESMTP id E27C81CA80; Fri, 22 Mar 2024 14:10:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=37.205.14.76 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711116632; cv=none; b=P8OLKkKkeRx3y+59w4i004huBjv9WfWVe8A1DLjEKu9qx9oIDTxxH6Cxlidfe7KWZpgH/IoDQsTPkNk/MbZBMCPzyD4wXI9kc4FmhUYRELJXQOJUteaDPQNS+hv9hNJ31U0iSPZwHM4C+RbZfx3CGUx72fezWmJqn3uyKF4Pz0w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711116632; c=relaxed/simple; bh=oQuYmWVqALX8DuaBrS27WLrJOU8gMDweyWEs5gjnIaI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=BLFoS50s03dLib3Hj3lXUwHhg6497atvoiem/RMu9MRLtt+wn8nfCXM1Gk04tQGps3I84zOE8nDXag2ksF3XM2rXsKqPfu982Dw3xFfhw8i6MqPzV8Hn1BwS1s12meCGavkn0M9rYKWqfoPHKzTWdjT0pISDMa6HGBUiEzUhXJY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=gpxsee.org; spf=pass smtp.mailfrom=gpxsee.org; arc=none smtp.client-ip=37.205.14.76 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=gpxsee.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gpxsee.org Received: from mgb4.. (unknown [62.77.71.229]) by mx.gpxsee.org (Postfix) with ESMTPSA id 8E6A367184; Fri, 22 Mar 2024 15:10:22 +0100 (CET) From: tumic@gpxsee.org To: Mauro Carvalho Chehab , Hans Verkuil Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, =?utf-8?q?Mar?= =?utf-8?q?tin_T=C5=AFma?= Subject: [PATCH v4 3/3] media: mgb4: Fixed signal frame rate limit handling Date: Fri, 22 Mar 2024 16:10:05 +0100 Message-ID: <20240322151005.3499-4-tumic@gpxsee.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240322151005.3499-1-tumic@gpxsee.org> References: <20240322151005.3499-1-tumic@gpxsee.org> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Martin Tůma Properly document the function of the mgb4 output frame_rate sysfs parameter and fix the corner case when the frame rate is set to zero causing a "divide by zero" kernel panic. Signed-off-by: Martin Tůma --- Documentation/admin-guide/media/mgb4.rst | 8 ++++++-- drivers/media/pci/mgb4/mgb4_sysfs_out.c | 9 +++++---- drivers/media/pci/mgb4/mgb4_vout.c | 12 ++++++------ drivers/media/pci/mgb4/mgb4_vout.h | 2 +- 4 files changed, 18 insertions(+), 13 deletions(-) diff --git a/Documentation/admin-guide/media/mgb4.rst b/Documentation/admin-guide/media/mgb4.rst index 2977f74d7e26..6fff886003e2 100644 --- a/Documentation/admin-guide/media/mgb4.rst +++ b/Documentation/admin-guide/media/mgb4.rst @@ -228,8 +228,12 @@ Common FPDL3/GMSL output parameters open.* **frame_rate** (RW): - Output video frame rate in frames per second. The default frame rate is - 60Hz. + Output video signal frame rate limit in frames per second. Due to + the limited output pixel clock steps, the card can not always generate + a frame rate perfectly matching the value required by the connected display. + Using this parameter one can limit the frame rate by "crippling" the signal + so that the lines are not equal but the signal appears like having the exact + frame rate to the connected display. The default frame rate limit is 60Hz. **hsync_polarity** (RW): HSYNC signal polarity. diff --git a/drivers/media/pci/mgb4/mgb4_sysfs_out.c b/drivers/media/pci/mgb4/mgb4_sysfs_out.c index f67ff2a48329..573aa61c69d4 100644 --- a/drivers/media/pci/mgb4/mgb4_sysfs_out.c +++ b/drivers/media/pci/mgb4/mgb4_sysfs_out.c @@ -229,9 +229,9 @@ static ssize_t frame_rate_show(struct device *dev, struct video_device *vdev = to_video_device(dev); struct mgb4_vout_dev *voutdev = video_get_drvdata(vdev); u32 period = mgb4_read_reg(&voutdev->mgbdev->video, - voutdev->config->regs.frame_period); + voutdev->config->regs.frame_limit); - return sprintf(buf, "%u\n", MGB4_HW_FREQ / period); + return sprintf(buf, "%u\n", period ? MGB4_HW_FREQ / period : 0); } /* @@ -245,14 +245,15 @@ static ssize_t frame_rate_store(struct device *dev, struct video_device *vdev = to_video_device(dev); struct mgb4_vout_dev *voutdev = video_get_drvdata(vdev); unsigned long val; - int ret; + int limit, ret; ret = kstrtoul(buf, 10, &val); if (ret) return ret; + limit = val ? MGB4_HW_FREQ / val : 0; mgb4_write_reg(&voutdev->mgbdev->video, - voutdev->config->regs.frame_period, MGB4_HW_FREQ / val); + voutdev->config->regs.frame_limit, limit); return count; } diff --git a/drivers/media/pci/mgb4/mgb4_vout.c b/drivers/media/pci/mgb4/mgb4_vout.c index a6b55669f0a8..cd001ceaae63 100644 --- a/drivers/media/pci/mgb4/mgb4_vout.c +++ b/drivers/media/pci/mgb4/mgb4_vout.c @@ -680,12 +680,12 @@ static void fpga_init(struct mgb4_vout_dev *voutdev) mgb4_write_reg(video, regs->config, 0x00000011); mgb4_write_reg(video, regs->resolution, (DEFAULT_WIDTH << 16) | DEFAULT_HEIGHT); - mgb4_write_reg(video, regs->hsync, 0x00102020); - mgb4_write_reg(video, regs->vsync, 0x40020202); - mgb4_write_reg(video, regs->frame_period, DEFAULT_PERIOD); + mgb4_write_reg(video, regs->hsync, 0x00283232); + mgb4_write_reg(video, regs->vsync, 0x40141F1E); + mgb4_write_reg(video, regs->frame_limit, DEFAULT_PERIOD); mgb4_write_reg(video, regs->padding, 0x00000000); - voutdev->freq = mgb4_cmt_set_vout_freq(voutdev, 70000 >> 1) << 1; + voutdev->freq = mgb4_cmt_set_vout_freq(voutdev, 61150 >> 1) << 1; mgb4_write_reg(video, regs->config, (voutdev->config->id + MGB4_VIN_DEVICES) << 2 | 1 << 4); @@ -711,8 +711,8 @@ static void debugfs_init(struct mgb4_vout_dev *voutdev) voutdev->regs[3].offset = voutdev->config->regs.hsync; voutdev->regs[4].name = "VIDEO_PARAMS_2"; voutdev->regs[4].offset = voutdev->config->regs.vsync; - voutdev->regs[5].name = "FRAME_PERIOD"; - voutdev->regs[5].offset = voutdev->config->regs.frame_period; + voutdev->regs[5].name = "FRAME_LIMIT"; + voutdev->regs[5].offset = voutdev->config->regs.frame_limit; voutdev->regs[6].name = "PADDING_PIXELS"; voutdev->regs[6].offset = voutdev->config->regs.padding; if (has_timeperframe(video)) { diff --git a/drivers/media/pci/mgb4/mgb4_vout.h b/drivers/media/pci/mgb4/mgb4_vout.h index ab9b58b1deb7..adc8fe1e7ae6 100644 --- a/drivers/media/pci/mgb4/mgb4_vout.h +++ b/drivers/media/pci/mgb4/mgb4_vout.h @@ -19,7 +19,7 @@ struct mgb4_vout_regs { u32 config; u32 status; u32 resolution; - u32 frame_period; + u32 frame_limit; u32 hsync; u32 vsync; u32 padding;