From patchwork Mon May 17 20:00:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dario Binacchi X-Patchwork-Id: 441481 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5DE17C433B4 for ; Mon, 17 May 2021 20:00:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31C06611ED for ; Mon, 17 May 2021 20:00:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237040AbhEQUB2 (ORCPT ); Mon, 17 May 2021 16:01:28 -0400 Received: from smtp-35.italiaonline.it ([213.209.10.35]:38706 "EHLO libero.it" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S236924AbhEQUB2 (ORCPT ); Mon, 17 May 2021 16:01:28 -0400 Received: from passgat-Modern-14-A10M.homenet.telecomitalia.it ([95.244.94.151]) by smtp-35.iol.local with ESMTPA id ijPJlPskepK9wijPOlg8K1; Mon, 17 May 2021 22:00:10 +0200 x-libjamoibt: 1601 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=libero.it; s=s2021; t=1621281610; bh=bmTisJb+Ff59TMYcwLQsU4X2sboin/EAdkin3u48soc=; h=From; b=ipCc4zaacXyEz5YcaJpohSdlkNoXd9Fg/nq+WS/nTGAEH6xiPFc/3iKC4HZbBR4Zt 2rzEsravy7ij50oKlYhsSuKCrdYdwpTDH69cby/+dMJKDeT9JEdqbKw572jWPTt/5c ERT9oeUKjcVUKjZ7N+eijMI0een+bDhV6MfjPsDl2HjF7We0NNHOuw4l9Iyxgqk0gM tBKbg2QlVTVjtK93+KQH1ABAB9z9lcnhWFFST8vka5P637kZHIIPYdTZE8YiPcPMf/ FQfNpiuYSCSKg2+YX9tgQ5iIFxohLS9vH/06+u3+5w322CeM0yz4sHTIkdgLXUpb07 /NAd7CP5sIppw== X-CNFS-Analysis: v=2.4 cv=A9ipg4aG c=1 sm=1 tr=0 ts=60a2cb4a cx=a_exe a=ugxisoNCKEotYwafST++Mw==:117 a=ugxisoNCKEotYwafST++Mw==:17 a=iV3ucFmErjs7te-rZ_sA:9 From: Dario Binacchi To: linux-kernel@vger.kernel.org Cc: Dario Binacchi , Linus Walleij , linux-gpio@vger.kernel.org Subject: [PATCH v2 1/2] pinctrl: core: configure pinmux from pins debug file Date: Mon, 17 May 2021 22:00:01 +0200 Message-Id: <20210517200002.6316-2-dariobin@libero.it> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210517200002.6316-1-dariobin@libero.it> References: <20210517200002.6316-1-dariobin@libero.it> X-CMAE-Envelope: MS4xfLx0TcvsHrcNzWtXVUq2wnkrd0xhmWrjEbSoW6Ku1Z8AF22pM/q3NjEFbkV2TsjpISAkxXAtRiSkOL2CLimlcchLMAld5RvLTAWjmgu41doM+ugAko0U Pf0V2GaozQMdFjBk+I0BEY75PO6EApb0dptS1qg5PBHWnivCmaQRHoHLMxGQ8MJeWkxgN0MI61rTWWze+zMefaIWVWX+4Gp0g7CA6Rl+7wewgShlEj3WalQv FC5HS7e8A73VJwSdlrhMBqs4OdadZNSCUSgDI7g6BlRc9RAIMgykgaErsjJQQ3IFiHJwubEqLaU0YQOrLcyhl47wU6oIjg/7x+4VWHBwazhfgqOsPAa0wvw3 a0YU3G09 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org The MPUs of some architectures (e.g AM335x) must be in privileged operating mode to write on the pinmux registers. In such cases, where writes will not work from user space, now it can be done from the pins debug file if the platform driver exports the pin_dbg_set() helper among the registered operations. Signed-off-by: Dario Binacchi --- (no changes since v1) drivers/pinctrl/core.c | 56 +++++++++++++++++++++++++++++++-- include/linux/pinctrl/pinctrl.h | 2 ++ 2 files changed, 56 insertions(+), 2 deletions(-) diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index a4ac87c8b4f8..f5c9a7d44039 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -1620,6 +1620,46 @@ EXPORT_SYMBOL_GPL(pinctrl_pm_select_idle_state); #ifdef CONFIG_DEBUG_FS +static ssize_t pinctrl_pins_write(struct file *file, + const char __user *user_buf, size_t count, + loff_t *ppos) +{ + struct seq_file *s = file->private_data; + struct pinctrl_dev *pctldev = s->private; + const struct pinctrl_ops *ops = pctldev->desc->pctlops; + char buf[32]; + char *c = &buf[0]; + char *token; + int ret, buf_size; + unsigned int i, pin; + + if (!ops->pin_dbg_set) + return -EFAULT; + + /* Get userspace string and assure termination */ + buf_size = min(count, sizeof(buf) - 1); + if (copy_from_user(buf, user_buf, buf_size)) + return -EFAULT; + + buf[buf_size] = 0; + token = strsep(&c, " "); + if (kstrtouint(token, 0, &pin)) + return -EINVAL; + + for (i = 0; i < pctldev->desc->npins; i++) { + if (pin != pctldev->desc->pins[i].number) + continue; + + ret = ops->pin_dbg_set(pctldev, pin, c); + if (ret) + return ret; + + return count; + } + + return -EINVAL; +} + static int pinctrl_pins_show(struct seq_file *s, void *what) { struct pinctrl_dev *pctldev = s->private; @@ -1677,7 +1717,11 @@ static int pinctrl_pins_show(struct seq_file *s, void *what) return 0; } -DEFINE_SHOW_ATTRIBUTE(pinctrl_pins); + +static int pinctrl_pins_open(struct inode *inode, struct file *file) +{ + return single_open(file, pinctrl_pins_show, inode->i_private); +} static int pinctrl_groups_show(struct seq_file *s, void *what) { @@ -1886,6 +1930,14 @@ static int pinctrl_show(struct seq_file *s, void *what) } DEFINE_SHOW_ATTRIBUTE(pinctrl); +static const struct file_operations pinctrl_pins_fops = { + .open = pinctrl_pins_open, + .read = seq_read, + .write = pinctrl_pins_write, + .llseek = seq_lseek, + .release = single_release, +}; + static struct dentry *debugfs_root; static void pinctrl_init_device_debugfs(struct pinctrl_dev *pctldev) @@ -1915,7 +1967,7 @@ static void pinctrl_init_device_debugfs(struct pinctrl_dev *pctldev) dev_name(pctldev->dev)); return; } - debugfs_create_file("pins", 0444, + debugfs_create_file("pins", 0644, device_root, pctldev, &pinctrl_pins_fops); debugfs_create_file("pingroups", 0444, device_root, pctldev, &pinctrl_groups_fops); diff --git a/include/linux/pinctrl/pinctrl.h b/include/linux/pinctrl/pinctrl.h index 70b45d28e7a9..6db4a775f549 100644 --- a/include/linux/pinctrl/pinctrl.h +++ b/include/linux/pinctrl/pinctrl.h @@ -95,6 +95,8 @@ struct pinctrl_ops { unsigned *num_pins); void (*pin_dbg_show) (struct pinctrl_dev *pctldev, struct seq_file *s, unsigned offset); + int (*pin_dbg_set) (struct pinctrl_dev *pctldev, unsigned int offset, + char *buf); int (*dt_node_to_map) (struct pinctrl_dev *pctldev, struct device_node *np_config, struct pinctrl_map **map, unsigned *num_maps); From patchwork Mon May 17 20:00:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dario Binacchi X-Patchwork-Id: 440335 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35A19C43461 for ; Mon, 17 May 2021 20:00:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 158456134F for ; Mon, 17 May 2021 20:00:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237105AbhEQUB3 (ORCPT ); Mon, 17 May 2021 16:01:29 -0400 Received: from smtp-35.italiaonline.it ([213.209.10.35]:58004 "EHLO libero.it" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S237019AbhEQUB2 (ORCPT ); Mon, 17 May 2021 16:01:28 -0400 Received: from passgat-Modern-14-A10M.homenet.telecomitalia.it ([95.244.94.151]) by smtp-35.iol.local with ESMTPA id ijPJlPskepK9wijPOlg8KC; Mon, 17 May 2021 22:00:11 +0200 x-libjamoibt: 1601 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=libero.it; s=s2021; t=1621281611; bh=CpKSAgnDhnImU3h7WHVy/pL3FGdxgW6Xn2Btiu3BZtk=; h=From; b=JstouEqnutiKDR803YxYAyHmN1QcDjFD28nyfBRLhD4HIv11sSRrbXO8JFC+HLDiG kzOMrBtUQUQYbVCFtYG+lo+zh9vCWgVLnXMC7RE2qOpVSpglVKnwA1xxye5H7s2lsh Gzt1bw6QwHbkq7LPytGMiIaJ76/fevk6C2dzPezaGIieExsDVdIzVHnK8HpeYjkMq/ iujd2wPVGespr7S1Y78IkdkMhjm+vA3KkCxDBxfbUT9hxdpEN17xe1zz2ITFptYbYR ymrJu9B33Xtw7R1XswDh1abg6ExmukMsBrkEXwpowis+Kc5D7NgzGdmDqY+n63VeBO bNDbL7YLsUOnA== X-CNFS-Analysis: v=2.4 cv=A9ipg4aG c=1 sm=1 tr=0 ts=60a2cb4b cx=a_exe a=ugxisoNCKEotYwafST++Mw==:117 a=ugxisoNCKEotYwafST++Mw==:17 a=sozttTNsAAAA:8 a=hlofsd_XEJyvNm5uEDwA:9 a=aeg5Gbbo78KNqacMgKqU:22 From: Dario Binacchi To: linux-kernel@vger.kernel.org Cc: Dario Binacchi , Haojian Zhuang , Linus Walleij , Tony Lindgren , linux-arm-kernel@lists.infradead.org, linux-gpio@vger.kernel.org, linux-omap@vger.kernel.org Subject: [PATCH v2 2/2] pinctrl: single: set pinmux from pins debug file Date: Mon, 17 May 2021 22:00:02 +0200 Message-Id: <20210517200002.6316-3-dariobin@libero.it> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210517200002.6316-1-dariobin@libero.it> References: <20210517200002.6316-1-dariobin@libero.it> X-CMAE-Envelope: MS4xfFli/etZ/wE7L2UP5E0I4DUHCnc++t8yiL/HFQ5l9ZzB5Qp1dwXk3nPydVRszxe3HqI18CFV6eVjElNdcJNRGkbW3hCuntRHl0xDKuN4yDC2oN2ir9Iz a/KM8ZQG0CHvsyeSDoJ/+56aqClDlrfEAyrQ5dTojO3Px4iYzRGCaXpUYgbyE294IHWdFzVWWotJlqIXkYb2U7rmY904C9UUA1FGhKRriK/IM40TKyjDA1PM yhcCsm7yO6j9g79WQLEBmXsnu0pFz9kxKzY2lPRhLdBV6kG02utv8/KqgKszOYoNobWgBu2X2ZB+2tKXbKHbKOK0pY+cKeF2jhc1DnOO7g8XuTdQBqZ9AkIa WBcoztwBg/oXWhK3+lOPrrw6lVXX93O8u7ozYEsI8B1xWUyHX061TPTEy4ZNQpZ/3D84Mmf6FcioPkMluKM3ybuL+Qq56mdy/su6P1XmEWMvY4mLBBVmNjc6 q6wzQTqXcY0h+ZL1QXifRDXnMmja5UEz7LjLCw== Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org As described in section 9.1 of the TI reference manual for AM335x [1], "For writing to the control module registers, the MPU will need to be in privileged mode of operation and writes will not work from user mode". By adding the pin_dbg_set helper to pcs_pinctrl_ops it will be possible to write these registers from the pins debug: cd /sys/kernel/debug/pinctrl/44e10800.pinmux-pinctrl-single/ echo >pins [1] https://www.ti.com/lit/ug/spruh73q/spruh73q.pdf Signed-off-by: Dario Binacchi --- Changes in v2: - Remove CONFIG_SOC_AM33XX dependency. drivers/pinctrl/pinctrl-single.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c index 2c9c9835f375..8497414e3384 100644 --- a/drivers/pinctrl/pinctrl-single.c +++ b/drivers/pinctrl/pinctrl-single.c @@ -313,6 +313,23 @@ static void pcs_pin_dbg_show(struct pinctrl_dev *pctldev, seq_printf(s, "%zx %08x %s ", pa, val, DRIVER_NAME); } +static int pcs_pin_dbg_set(struct pinctrl_dev *pctldev, unsigned int pin, + char *buf) +{ + struct pcs_device *pcs; + unsigned int val, mux_bytes; + + buf = skip_spaces(buf); + if (kstrtouint(buf, 0, &val)) + return -EINVAL; + + pcs = pinctrl_dev_get_drvdata(pctldev); + + mux_bytes = pcs->width / BITS_PER_BYTE; + pcs->write(val, pcs->base + pin * mux_bytes); + return 0; +} + static void pcs_dt_free_map(struct pinctrl_dev *pctldev, struct pinctrl_map *map, unsigned num_maps) { @@ -331,6 +348,9 @@ static const struct pinctrl_ops pcs_pinctrl_ops = { .get_group_name = pinctrl_generic_get_group_name, .get_group_pins = pinctrl_generic_get_group_pins, .pin_dbg_show = pcs_pin_dbg_show, +#if IS_ENABLED(CONFIG_DEVMEM) + .pin_dbg_set = pcs_pin_dbg_set, +#endif .dt_node_to_map = pcs_dt_node_to_map, .dt_free_map = pcs_dt_free_map, };