From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751403AbeAVOcZ (ORCPT ); Mon, 22 Jan 2018 09:32:25 -0500 Received: from mailout1.w1.samsung.com ([210.118.77.11]:48185 "EHLO mailout1.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751216AbeAVOah (ORCPT ); Mon, 22 Jan 2018 09:30:37 -0500 DKIM-Filter: OpenDKIM Filter v2.11.0 mailout1.w1.samsung.com 20180122143035euoutp0156f2fea95b49179276941985669bcde1~MKEE45V6O2790127901euoutp01k X-AuditID: cbfec7f5-f79d06d0000031c7-ac-5a65f58aa4a1 From: Maciej Purski To: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Cc: Mark Brown , Liam Girdwood , Rob Herring , Mark Rutland , Marek Szyprowski , Doug Anderson , Bartlomiej Zolnierkiewicz , Maciej Purski Subject: [PATCH v4 5/7] regulator: core: Resolve coupled regulators Date: Mon, 22 Jan 2018 15:30:10 +0100 Message-id: <1516631412-17542-6-git-send-email-m.purski@samsung.com> X-Mailer: git-send-email 2.7.4 In-reply-to: <1516631412-17542-1-git-send-email-m.purski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrAIsWRmVeSWpSXmKPExsWy7djP87pdX1OjDLadZrfYOGM9q8XUh0/Y LOYfOcdqcXbZQTaLb1c6mCwu75rDZrHg5S0Wi7VH7rJbLL1+kcmide8RdgcujzXz1jB6zG64 yOKxc9Zddo9NqzrZPPq2rGL0+LxJLoAtissmJTUnsyy1SN8ugSvj0OvXTAXNChW9d74yNjD2 SHUxcnJICJhI7Jn5kh3CFpO4cG89WxcjF4eQwFJGid7f51khnM+MErOnzWeH6djydDoTRGIZ o8S5BZ2sIAkhgf+MEtdXxHYxcnCwCWhJrGmPBwmLCNhIvL1xgBGknlngOJPE9akbmUBqhAWc JTpPOIPUsAioSsz5MZUFxOYVcJH41/uCCWKXnMTNc53MIDangKvEn76JLCBzJATWsElsvvaW FaLIRWLVzkdsELawxKvjW6AOlZG4PLmbBcKulrj4dRdUTY1E4+0NUDXWEp8nbQFbwCzAJzFp 23RmkNskBHglOtqEIEo8JM4snAJV7ihx4M0WaKDMYJQ42neFaQKj9AJGhlWMIqmlxbnpqcWm esWJucWleel6yfm5mxiB8Xz63/GvOxiXHrM6xCjAwajEw9thkBolxJpYVlyZe4hRgoNZSYQ3 bQVQiDclsbIqtSg/vqg0J7X4EKM0B4uSOK9tVFukkEB6YklqdmpqQWoRTJaJg1OqgZH3xs0X JX1FKZ5uFc0Kdw/V6Ze3zwvi6DzuemOTrELQLZWeCbcVPe4Xszbc0E47aLzS6alFzUaHunv7 aiatWCm8pVTtzGLWLQd/cU8/0eRennH4xpyFU9eJignu4p6cI9H0fr/M/Jvzhack/vm05GLr wfMhvNaym/prdqzcK3P1pfDLqM74/JtKLMUZiYZazEXFiQBS0bXh4wIAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrGLMWRmVeSWpSXmKPExsVy+t/xa7qdX1OjDD6807bYOGM9q8XUh0/Y LOYfOcdqcXbZQTaLb1c6mCwu75rDZrHg5S0Wi7VH7rJbLL1+kcmide8RdgcujzXz1jB6zG64 yOKxc9Zddo9NqzrZPPq2rGL0+LxJLoAtissmJTUnsyy1SN8ugSvj0OvXTAXNChW9d74yNjD2 SHUxcnJICJhIbHk6nQnCFpO4cG89WxcjF4eQwBJGiT/rm5khnEYmiaP3vgNlODjYBLQk1rTH gzSICNhIvL1xgBGkhlngJJPEn4vrGEFqhAWcJTpPOIPUsAioSsz5MZUFxOYVcJH41/sCapmc xM1zncwgNqeAq8SfvolgNUJANXsfvGGfwMi7gJFhFaNIamlxbnpusZFecWJucWleul5yfu4m RmDobTv2c8sOxq53wYcYBTgYlXh4OwxSo4RYE8uKK3MPMUpwMCuJ8KatAArxpiRWVqUW5ccX leakFh9ilOZgURLn7d2zOlJIID2xJDU7NbUgtQgmy8TBKdXA2KbdMXWvddNxP+bDy143BUp9 mBG//q7MmTrBe6nB1ZGa8YczO9bPuBVWqiK5vk+tVNggJvbqprK8ulliX9g5b9/sNn++8d3B uAmWz+ck2m399EzqYvG9Zbvadzv2MXucMmTSi5wUsz/RICCCI1Jt3YSm2sC0PhdtljNVe2tO ii62uPXORCNViaU4I9FQi7moOBEAO4CT0zkCAAA= X-CMS-MailID: 20180122143033eucas1p2adb3b39af238b2449486389d214a3a68 X-Msg-Generator: CA CMS-TYPE: 201P X-CMS-RootMailID: 20180122143033eucas1p2adb3b39af238b2449486389d214a3a68 X-RootMTR: 20180122143033eucas1p2adb3b39af238b2449486389d214a3a68 References: <1516631412-17542-1-git-send-email-m.purski@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Odroid XU3/4 and other Exynos5422 based boards there is a case, that different devices on the board are supplied by different regulators with non-fixed voltages. If one of these devices temporarily requires higher voltage, there might occur a situation that the spread between two devices' voltages is so high, that there is a risk of changing 'high' and 'low' states on the interconnection between devices powered by those regulators. Fill coupling descriptor with data obtained from DTS using previously defined of_functions. Fail to register a regulator, if some data inconsistency occurs. If some coupled regulators are not yet registered, don't fail to register, but try to resolve them in late init call. Signed-off-by: Maciej Purski --- drivers/regulator/core.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 92 insertions(+) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 1118527..3628949 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -3945,6 +3945,88 @@ static int regulator_register_resolve_supply(struct device *dev, void *data) return 0; } +static int regulator_fill_coupling_array(struct regulator_dev *rdev) +{ + struct coupling_desc *c_desc = &rdev->coupling_desc; + int n_coupled = c_desc->n_coupled; + struct regulator_dev *c_rdev; + int i; + + for (i = 1; i < n_coupled; i++) { + /* already resolved */ + if (c_desc->coupled_rdevs[i]) + continue; + + c_rdev = of_parse_coupled_regulator(rdev, i - 1); + + if (c_rdev) { + c_desc->coupled_rdevs[i] = c_rdev; + c_desc->n_resolved++; + } + } + + if (rdev->coupling_desc.n_resolved < n_coupled) + return -1; + else + return 0; +} + +static int regulator_register_fill_coupling_array(struct device *dev, + void *data) +{ + struct regulator_dev *rdev = dev_to_rdev(dev); + + if (regulator_fill_coupling_array(rdev)) + rdev_dbg(rdev, "unable to resolve coupling\n"); + + return 0; +} + +static int regulator_resolve_coupling(struct regulator_dev *rdev) +{ + int n_phandles = of_get_n_coupled(rdev); + + if (n_phandles + 1 > MAX_COUPLED) { + rdev_err(rdev, "too many regulators coupled\n"); + return -EPERM; + } + + /* + * Every regulator should always have coupling descriptor filled with + * at least pointer to itself. + */ + rdev->coupling_desc.coupled_rdevs[0] = rdev; + rdev->coupling_desc.n_coupled = n_phandles + 1; + rdev->coupling_desc.n_resolved++; + + /* regulator isn't coupled */ + if (n_phandles == 0) + return 0; + + /* regulator, which can't change its voltage, can't be coupled */ + if (!regulator_ops_is_valid(rdev, REGULATOR_CHANGE_VOLTAGE)) { + rdev_err(rdev, "voltage operation not allowed\n"); + return -EPERM; + } + + if (rdev->constraints->max_spread <= 0) { + rdev_err(rdev, "wrong max_spread value\n"); + return -EPERM; + } + + if (!of_check_coupling_data(rdev)) + return -EPERM; + + /* + * After everything has been checked, try to fill rdevs array + * with pointers to regulators parsed from device tree. If some + * regulators are not registered yet, retry in late init call + */ + regulator_fill_coupling_array(rdev); + + return 0; +} + /** * regulator_register - register regulator * @regulator_desc: regulator to register @@ -4077,6 +4159,13 @@ regulator_register(const struct regulator_desc *regulator_desc, if (ret < 0) goto wash; + mutex_lock(®ulator_list_mutex); + ret = regulator_resolve_coupling(rdev); + mutex_unlock(®ulator_list_mutex); + + if (ret != 0) + goto wash; + /* add consumers devices */ if (init_data) { mutex_lock(®ulator_list_mutex); @@ -4565,6 +4654,9 @@ static int __init regulator_init_complete(void) class_for_each_device(®ulator_class, NULL, NULL, regulator_late_cleanup); + class_for_each_device(®ulator_class, NULL, NULL, + regulator_register_fill_coupling_array); + return 0; } late_initcall_sync(regulator_init_complete); -- 2.7.4