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{ "id": 2223417, "url": "http://patchwork.ozlabs.org/api/covers/2223417/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pwm/cover/20260415094908.1539-1-dongxuyang@eswincomputing.com/", "project": { "id": 38, "url": "http://patchwork.ozlabs.org/api/projects/38/?format=api", "name": "Linux PWM development", "link_name": "linux-pwm", "list_id": "linux-pwm.vger.kernel.org", "list_email": "linux-pwm@vger.kernel.org", "web_url": "", "scm_url": "", "webscm_url": "", "list_archive_url": "", "list_archive_url_format": "", "commit_url_format": "" }, "msgid": "<20260415094908.1539-1-dongxuyang@eswincomputing.com>", "list_archive_url": null, "date": "2026-04-15T09:49:08", "name": "[v4,0/2] Update designware pwm driver", "submitter": { "id": 90849, "url": "http://patchwork.ozlabs.org/api/people/90849/?format=api", "name": "Xuyang Dong", "email": "dongxuyang@eswincomputing.com" }, "mbox": "http://patchwork.ozlabs.org/project/linux-pwm/cover/20260415094908.1539-1-dongxuyang@eswincomputing.com/mbox/", "series": [ { "id": 499954, "url": "http://patchwork.ozlabs.org/api/series/499954/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pwm/list/?series=499954", "date": "2026-04-15T09:49:08", "name": "Update designware pwm driver", "version": 4, "mbox": "http://patchwork.ozlabs.org/series/499954/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2223417/comments/", "headers": { "Return-Path": "\n <linux-pwm+bounces-8583-incoming=patchwork.ozlabs.org@vger.kernel.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linux-pwm@vger.kernel.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c0a:e001:db::12fc:5321; helo=sea.lore.kernel.org;\n envelope-from=linux-pwm+bounces-8583-incoming=patchwork.ozlabs.org@vger.kernel.org;\n receiver=patchwork.ozlabs.org)", "smtp.subspace.kernel.org;\n arc=none smtp.client-ip=13.76.78.106", "smtp.subspace.kernel.org;\n dmarc=none (p=none dis=none) header.from=eswincomputing.com", "smtp.subspace.kernel.org;\n spf=pass smtp.mailfrom=eswincomputing.com" ], "Received": [ "from sea.lore.kernel.org (sea.lore.kernel.org\n [IPv6:2600:3c0a:e001:db::12fc:5321])\n\t(using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)\n\t key-exchange x25519)\n\t(No client certificate requested)\n\tby legolas.ozlabs.org (Postfix) with ESMTPS id 4fwc3n3p40z1yHM\n\tfor <incoming@patchwork.ozlabs.org>; Wed, 15 Apr 2026 19:56:21 +1000 (AEST)", "from smtp.subspace.kernel.org (conduit.subspace.kernel.org\n [100.90.174.1])\n\tby sea.lore.kernel.org (Postfix) with ESMTP id 4829031294EB\n\tfor <incoming@patchwork.ozlabs.org>; Wed, 15 Apr 2026 09:49:48 +0000 (UTC)", "from localhost.localdomain (localhost.localdomain [127.0.0.1])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id 1B1D733F5BD;\n\tWed, 15 Apr 2026 09:49:45 +0000 (UTC)", "from azure-sdnproxy.icoremail.net (azure-sdnproxy.icoremail.net\n [13.76.78.106])\n\tby smtp.subspace.kernel.org (Postfix) with ESMTP id 13AC533A9E2;\n\tWed, 15 Apr 2026 09:49:39 +0000 (UTC)", "from E0005152DT.eswin.cn (unknown [10.12.96.41])\n\tby app2 (Coremail) with SMTP id TQJkCgBXbaAWX99pReMRAA--.51076S2;\n\tWed, 15 Apr 2026 17:49:12 +0800 (CST)" ], "ARC-Seal": "i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116;\n\tt=1776246584; cv=none;\n b=e0S5dBSuyXOjiOiInRWbVkE+U1/pM+GvJ31HTaAannSjJ9Z2ArHMOlxvkm2AP2UsdrA0OQDOutQ6XIJi4oWQecS3c53zaLQoKrzHNUQFEnbV4k7WWyHU/kg6bTA/83zHg63NYuFcj70b8KL3ZSbOygPoQjio7OEitzJ1lBHbOlM=", "ARC-Message-Signature": "i=1; a=rsa-sha256; d=subspace.kernel.org;\n\ts=arc-20240116; t=1776246584; c=relaxed/simple;\n\tbh=DYVFNdk+djD8K61KVIPUXoIqm13LT4O06uqmf+HTNoY=;\n\th=From:To:Cc:Subject:Date:Message-Id:MIME-Version;\n b=OjT9V6ecONQfOzo+x4GKfTT9yoXxle1fSz9+1CnRa8v7Pf8eqxxAQgVcJKB61G9I+ZPCq0/4MY+2Q+pyJ89Nl0TolPMC5zc1yfnKAW/2jG1iW6Th+jkM73nwc4cfN+h40M17Su8IkLXhA0MtGeAl1pp955m56C75971IH4CSVoU=", "ARC-Authentication-Results": "i=1; smtp.subspace.kernel.org;\n dmarc=none (p=none dis=none) header.from=eswincomputing.com;\n spf=pass smtp.mailfrom=eswincomputing.com;\n arc=none smtp.client-ip=13.76.78.106", "From": "dongxuyang@eswincomputing.com", "To": "ukleinek@kernel.org,\n\trobh@kernel.org,\n\tkrzk+dt@kernel.org,\n\tconor+dt@kernel.org,\n\tben-linux@fluff.org,\n\tben.dooks@codethink.co.uk,\n\tp.zabel@pengutronix.de,\n\tlinux-pwm@vger.kernel.org,\n\tdevicetree@vger.kernel.org,\n\tlinux-kernel@vger.kernel.org", "Cc": "ningyu@eswincomputing.com,\n\tlinmin@eswincomputing.com,\n\txuxiang@eswincomputing.com,\n\twangguosheng@eswincomputing.com,\n\tpinkesh.vaghela@einfochips.com,\n\tXuyang Dong <dongxuyang@eswincomputing.com>", "Subject": "[PATCH v4 0/2] Update designware pwm driver", "Date": "Wed, 15 Apr 2026 17:49:08 +0800", "Message-Id": "<20260415094908.1539-1-dongxuyang@eswincomputing.com>", "X-Mailer": "git-send-email 2.31.1.windows.1", "Precedence": "bulk", "X-Mailing-List": "linux-pwm@vger.kernel.org", "List-Id": "<linux-pwm.vger.kernel.org>", "List-Subscribe": "<mailto:linux-pwm+subscribe@vger.kernel.org>", "List-Unsubscribe": "<mailto:linux-pwm+unsubscribe@vger.kernel.org>", "MIME-Version": "1.0", "Content-Transfer-Encoding": "8bit", "X-CM-TRANSID": "TQJkCgBXbaAWX99pReMRAA--.51076S2", "X-Coremail-Antispam": "1UD129KBjvJXoWxAF1rZw4rXw1xJF1ktr4fZrb_yoWrKrWxpF\n\tW8KrWakrWkWrySgan7X3W8uFyYq3Z5JF4UKwn5Ga4UZw1Yy3yUJrZY9Fy5tF9Fvr4kWFyY\n\tyryfGa129a4YyF7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2\n\t9KBjDU0xBIdaVrnRJUUUBv14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0\n\trVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02\n\t1l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U\n\tJVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc\n\tCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E\n\t2Ix0cI8IcVAFwI0_Jrv_JF1lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWUJV\n\tW8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1lFIxGxcIEc7CjxVA2\n\tY2ka0xkIwI1lw4CEc2x0rVAKj4xxMxkF7I0En4kS14v26r1q6r43MxkIecxEwVCm-wCF04\n\tk20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18\n\tMI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr4\n\t1lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1l\n\tIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4\n\tA2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUHCJQUUUUU=", "X-CM-SenderInfo": "pgrqw5xx1d0w46hv4xpqfrz1xxwl0woofrz/" }, "content": "From: Xuyang Dong <dongxuyang@eswincomputing.com>\n\nThere is already a patch [1] for the DesignWare PWM driver,\nwhich is posted by Ben and still under review.\nBased on this patch, this series is a continuation of [1]\nto add support for IP versions 2.11a and later, which\nincludes support for \"Pulse Width Modulation with 0%\nand 100% Duty Cycle\".\n\nSupported chips:\nESWIN EIC7700 series SoC.\n\nTest:\nTested this patch on the Sifive HiFive Premier P550 (which uses the EIC7700\nSoC).\n\n[1] https://lore.kernel.org/lkml/20230907161242.67190-1-ben.dooks@codethink.co.uk/\n\nUpdates:\n Change in v4:\n - YAML:\n - Change maxItems from 1 to 2. As there is a corresponding reset signal\n for each clock domain, the effective maxItems of the resets property\n is set to 2.\n - Update the YAML commit message to describe the hardware.\n - Driver:\n - Replace devm_reset_control_get_optional_exclusive() with\n devm_reset_control_array_get_optional_exclusive(). Since the number\n of reset signals has increased from one to two.\n\n - Link to v3: https://lore.kernel.org/all/20260402091718.1608-1-dongxuyang@eswincomputing.com/\n\n Change in v3:\n - YAML:\n - Added a clear justification for the optional resets property. It is\n required to support proper controller initialization when no PWM\n channel is active at boot time, while allowing the driver to skip\n reset deassertion if any channel is already enabled.\n - Driver:\n - Update the boundary value check of tmp in __dwc_pwm_configure_timer()\n for DWC_TIM_CTRL_0N100PWM_EN.\n - Replace 'sizeof(struct dwc_pwm_drvdata)' with\n 'struct_size(data, chips, 1)'.\n - Drop devm_clk_get_enabled() in favor of devm_clk_get() with explicit\n clk_prepare_enable() and clk_disable_unprepare() allowing runtime PM\n to manage clock state.\n - Replace devm_reset_control_get_optional_exclusive_deasserted() with\n devm_reset_control_get_optional_exclusive() and issue a full reset via\n reset_control_reset() only when no PWM channel is active at probe time.\n - Detect bootloader-enabled PWM channels by reading the enable bit, and\n initialize runtime PM as active for those channels by calling\n pm_runtime_set_active() and pm_runtime_get_noresume().\n - Remove autosuspend as it is not required for this driver.\n - Use explicit pm_runtime_enable() and pm_runtime_disable() instead of\n the managed devm_pm_runtime_enable() variant to ensure correct cleanup.\n - On device removal, recheck the channel enable status. If any channel\n remains active, call pm_runtime_put_noidle() before disabling clocks\n via clk_disable_unprepare().\n Resume device before register access during removal if it is runtime\n suspended, and re-suspend it afterward.\n - If device is suspended, resume it before register access during system\n resume/suspend.\n - Use pm_ptr() instead of pm_sleep_ptr() for correct PM operation.\n\n - Link to v2: https://lore.kernel.org/all/20260306093000.2065-1-dongxuyang@eswincomputing.com/\n\n Change in v2:\n - YAML:\n - Remove eswin,eic7700-pwm.yaml. Use snps,dw-apb-timers-pwm2.yaml.\n The description in snps,dw-apb-timers-pwm2.yaml is better.\n - Add the resets property as optional, as defined in the databook.\n - Remove snps,pwm-full-range-enable as no additional property is needed.\n - Driver:\n - Change the file from pwm-dwc-eic7700.c to pwm-dwc-of.c from [1].\n - Define DWC_TIM_VERSION_ID_2_11A 2.11a as the baseline version.\n - Enable the 0% and 100% duty cycle mode by setting dwc->feature if\n the version read from the TIMERS_COMP_VERSION register is later\n than or equal to DWC_TIM_VERSION_ID_2_11A.\n - Use the DIV_ROUND_UP_ULL() to calculate width in the .apply and\n .get_state.\n - Additionally, Power Management (PM) support has been added to the\n pwm-dwc-of.c driver.\n - Drop the headers that are not used.\n - Use devm_clk_get_enabled() instead of devm_clk_get().\n - Drop of_match_ptr.\n - Fix build error with 1ULL << 32.\n Reported-by: kernel test robot <lkp@intel.com>\n Closes: https://lore.kernel.org/oe-kbuild-all/202512061720.j31AsgM7-lkp@intel.com/\n\n - Link to v1: https://lore.kernel.org/all/20251205090411.1388-1-dongxuyang@eswincomputing.com/\n - Link to v9: https://lore.kernel.org/lkml/20230907161242.67190-1-ben.dooks@codethink.co.uk/\n\nXuyang Dong (2):\n dt-bindings: pwm: dwc: add reset optional\n pwm: dwc: add of/platform support\n\n .../bindings/pwm/snps,dw-apb-timers-pwm2.yaml | 3 +\n drivers/pwm/Kconfig | 10 +\n drivers/pwm/Makefile | 1 +\n drivers/pwm/pwm-dwc-core.c | 101 ++++--\n drivers/pwm/pwm-dwc-of.c | 331 ++++++++++++++++++\n drivers/pwm/pwm-dwc.h | 25 +-\n 6 files changed, 442 insertions(+), 29 deletions(-)\n create mode 100644 drivers/pwm/pwm-dwc-of.c\n\n--\n2.34.1" }