From patchwork Wed Apr 18 13:18:04 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 10348131 X-Patchwork-Delegate: geert@linux-m68k.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 D66046031B for ; Wed, 18 Apr 2018 13:18:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C8125285A7 for ; Wed, 18 Apr 2018 13:18:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BCE58285EA; Wed, 18 Apr 2018 13:18:48 +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=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI 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 2C84F285A7 for ; Wed, 18 Apr 2018 13:18:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753847AbeDRNSr (ORCPT ); Wed, 18 Apr 2018 09:18:47 -0400 Received: from baptiste.telenet-ops.be ([195.130.132.51]:33910 "EHLO baptiste.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753780AbeDRNSJ (ORCPT ); Wed, 18 Apr 2018 09:18:09 -0400 Received: from ayla.of.borg ([84.194.111.163]) by baptiste.telenet-ops.be with bizsmtp id bpJ71x0033XaVaC01pJ73S; Wed, 18 Apr 2018 15:18:07 +0200 Received: from ramsan.of.borg ([192.168.97.29] helo=ramsan) by ayla.of.borg with esmtp (Exim 4.86_2) (envelope-from ) id 1f8myN-00056T-0Y; Wed, 18 Apr 2018 15:18:07 +0200 Received: from geert by ramsan with local (Exim 4.86_2) (envelope-from ) id 1f8myM-0006cF-Vm; Wed, 18 Apr 2018 15:18:06 +0200 From: Geert Uytterhoeven To: Marek Vasut , Lee Jones , Rob Herring , Mark Rutland , Liam Girdwood , Mark Brown Cc: linux-renesas-soc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH v3 4/4] regulator: bd9571mwv: Add support for backup mode Date: Wed, 18 Apr 2018 15:18:04 +0200 Message-Id: <1524057484-25350-5-git-send-email-geert+renesas@glider.be> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1524057484-25350-1-git-send-email-geert+renesas@glider.be> References: <1524057484-25350-1-git-send-email-geert+renesas@glider.be> Sender: linux-renesas-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The BD9571MWV PMIC supports backup mode, which keeps one or more DDR rails powered while the main SoC is powered down. Which DDR rails are to be kept powered is board-specific, and controlled using the optional "rohm,ddr-backup-power" DT property. In the absence of this property, backup mode is not available. Backup mode can be enabled or disabled by the user using the standard "wakeup" virtual file in sysfs, e.g. to enable: echo enabled > /sys/devices/platform/soc/e60b0000.i2c/i2c-7/7-0030/bd9571mwv-regulator.2.auto/power/wakeup When the PMIC is configured for backup mode, the role of the accessory power switch changes from a power switch to a wake-up switch. Two types of switches (or signals) can be used: A. With a momentary power switch (or pulse signal), the PMIC is configured for backup mode in the PMIC driver's suspend callback, during system suspend. Backup mode is enabled by default, as there is no further impact during normal system operation. B. With a toggle power switch (or level signal), the following steps must be followed exactly: 1. Configure PMIC for backup mode, 2. Switch accessory power switch off, to prepare for system suspend, which is a manual step not controlled by software, 3. Suspend system. This mode is not yet supported by the driver. As the switch type is board-specific, and cannot be determined automatically, it is obtained from the presence of one of the "rohm,rstbmode-*" properties in DT. Signed-off-by: Geert Uytterhoeven --- v3: - No changes, v2: - Use normal "wakeup" sysfs virtual file instead of adding our own "backup_mode" file, - Differentiate between momentary and toggle power switches: - Support for momentary switches is enabled automatically, - Toggle switches are not yet supported (but still work when backup mode is enabled using i2set from userspace). --- drivers/regulator/bd9571mwv-regulator.c | 127 +++++++++++++++++++++++++++++++- 1 file changed, 126 insertions(+), 1 deletion(-) diff --git a/drivers/regulator/bd9571mwv-regulator.c b/drivers/regulator/bd9571mwv-regulator.c index c67a83d53c4cb76b..be574eb444ebda97 100644 --- a/drivers/regulator/bd9571mwv-regulator.c +++ b/drivers/regulator/bd9571mwv-regulator.c @@ -24,6 +24,18 @@ #include +struct bd9571mwv_reg { + struct bd9571mwv *bd; + + /* DDR Backup Power */ + u8 bkup_mode_cnt_keepon; /* from "rohm,ddr-backup-power" */ + u8 bkup_mode_cnt_saved; + + /* Power switch type */ + bool rstbmode_level; + bool rstbmode_pulse; +}; + enum bd9571mwv_regulators { VD09, VD18, VD25, VD33, DVFS }; #define BD9571MWV_REG(_name, _of, _id, _ops, _vr, _vm, _nv, _min, _step, _lmin)\ @@ -131,14 +143,99 @@ static struct regulator_desc regulators[] = { 0x80, 600000, 10000, 0x3c), }; +#ifdef CONFIG_PM_SLEEP +static int bd9571mwv_bkup_mode_read(struct bd9571mwv *bd, unsigned int *mode) +{ + int ret; + + ret = regmap_read(bd->regmap, BD9571MWV_BKUP_MODE_CNT, mode); + if (ret) { + dev_err(bd->dev, "failed to read backup mode (%d)\n", ret); + return ret; + } + + return 0; +} + +static int bd9571mwv_bkup_mode_write(struct bd9571mwv *bd, unsigned int mode) +{ + int ret; + + ret = regmap_write(bd->regmap, BD9571MWV_BKUP_MODE_CNT, mode); + if (ret) { + dev_err(bd->dev, "failed to configure backup mode 0x%x (%d)\n", + mode, ret); + return ret; + } + + return 0; +} + +static int bd9571mwv_suspend(struct device *dev) +{ + struct bd9571mwv_reg *bdreg = dev_get_drvdata(dev); + unsigned int mode; + int ret; + + if (!device_may_wakeup(dev)) + return 0; + + /* Save DDR Backup Mode */ + ret = bd9571mwv_bkup_mode_read(bdreg->bd, &mode); + if (ret) + return ret; + + bdreg->bkup_mode_cnt_saved = mode; + + if (!bdreg->rstbmode_pulse) + return 0; + + /* Enable DDR Backup Mode */ + mode &= ~BD9571MWV_BKUP_MODE_CNT_KEEPON_MASK; + mode |= bdreg->bkup_mode_cnt_keepon; + + if (mode != bdreg->bkup_mode_cnt_saved) + return bd9571mwv_bkup_mode_write(bdreg->bd, mode); + + return 0; +} + +static int bd9571mwv_resume(struct device *dev) +{ + struct bd9571mwv_reg *bdreg = dev_get_drvdata(dev); + + if (!device_may_wakeup(dev)) + return 0; + + /* Restore DDR Backup Mode */ + return bd9571mwv_bkup_mode_write(bdreg->bd, bdreg->bkup_mode_cnt_saved); +} + +static const struct dev_pm_ops bd9571mwv_pm = { + SET_SYSTEM_SLEEP_PM_OPS(bd9571mwv_suspend, bd9571mwv_resume) +}; + +#define DEV_PM_OPS &bd9571mwv_pm +#else +#define DEV_PM_OPS NULL +#endif /* CONFIG_PM_SLEEP */ + static int bd9571mwv_regulator_probe(struct platform_device *pdev) { struct bd9571mwv *bd = dev_get_drvdata(pdev->dev.parent); struct regulator_config config = { }; + struct bd9571mwv_reg *bdreg; struct regulator_dev *rdev; + unsigned int val; int i; - platform_set_drvdata(pdev, bd); + bdreg = devm_kzalloc(&pdev->dev, sizeof(*bdreg), GFP_KERNEL); + if (!bdreg) + return -ENOMEM; + + bdreg->bd = bd; + + platform_set_drvdata(pdev, bdreg); config.dev = &pdev->dev; config.dev->of_node = bd->dev->of_node; @@ -155,6 +252,33 @@ static int bd9571mwv_regulator_probe(struct platform_device *pdev) } } + val = 0; + of_property_read_u32(bd->dev->of_node, "rohm,ddr-backup-power", &val); + if (val & ~BD9571MWV_BKUP_MODE_CNT_KEEPON_MASK) { + dev_err(bd->dev, "invalid %s mode %u\n", + "rohm,ddr-backup-power", val); + return -EINVAL; + } + bdreg->bkup_mode_cnt_keepon = val; + + bdreg->rstbmode_level = of_property_read_bool(bd->dev->of_node, + "rohm,rstbmode-level"); + bdreg->rstbmode_pulse = of_property_read_bool(bd->dev->of_node, + "rohm,rstbmode-pulse"); + if (bdreg->rstbmode_level && bdreg->rstbmode_pulse) { + dev_err(bd->dev, "only one rohm,rstbmode-* may be specified"); + return -EINVAL; + } + + if (bdreg->bkup_mode_cnt_keepon) { + device_set_wakeup_capable(&pdev->dev, true); + /* + * Wakeup is enabled by default in pulse mode, but needs + * explicit user setup in level mode. + */ + device_set_wakeup_enable(&pdev->dev, bdreg->rstbmode_pulse); + } + return 0; } @@ -167,6 +291,7 @@ MODULE_DEVICE_TABLE(platform, bd9571mwv_regulator_id_table); static struct platform_driver bd9571mwv_regulator_driver = { .driver = { .name = "bd9571mwv-regulator", + .pm = DEV_PM_OPS, }, .probe = bd9571mwv_regulator_probe, .id_table = bd9571mwv_regulator_id_table,