From patchwork Mon May 22 16:31:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Esteban Blanc X-Patchwork-Id: 684801 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07C4FC7EE2E for ; Mon, 22 May 2023 16:31:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232881AbjEVQbr (ORCPT ); Mon, 22 May 2023 12:31:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41166 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231848AbjEVQbq (ORCPT ); Mon, 22 May 2023 12:31:46 -0400 Received: from mail-wr1-x434.google.com (mail-wr1-x434.google.com [IPv6:2a00:1450:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 65F6D1AD for ; Mon, 22 May 2023 09:31:20 -0700 (PDT) Received: by mail-wr1-x434.google.com with SMTP id ffacd0b85a97d-30a992a9c3eso50867f8f.0 for ; Mon, 22 May 2023 09:31:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20221208.gappssmtp.com; s=20221208; t=1684773078; x=1687365078; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=aeRgb+2IQy9YLMHOmM6dxmEYQ6o/TExWO2LvlYPralc=; b=R2eRSweNwYOScNlU7dswEK45UIIszWqs7q0bCnbr3woXVjK/ReorWE3SV/i2p3ZH1z XFAsiXifP//oau8aAu8oukC3pLtOOE+WxViVYpJuhHgIJf1HpWQ4Vpo+nAFyqY3gBr64 jLnnw76COtiPuDZnGFWhUk/3SHGYLet4O/yfzqnD+NAzm9l1x7HXlUwQV5DEGNggCJiS vy422Z7jRUF2TtCJxH8eqxst+ngskqg9RajRTqhnbal+KbwaQq/ciU8aNdoMfCMKsjjS 3Uz/tff47qqqmyRaWwPK/zXZDMoMC3e+C1PhLMYI8ECrb/yVZtCgJMzSLA35VUXISgZZ LxyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684773078; x=1687365078; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=aeRgb+2IQy9YLMHOmM6dxmEYQ6o/TExWO2LvlYPralc=; b=DAgImrm0zr7Ey8D6O6xLxaQ+ONVRHu/TebqGGu80EOYXXWkuuuE9Wa7/vLsNeBfPPN VNS54Mqhs8nOavOElgIfbPDscdRoPGy5h1HTRru/JQzXcHX2W4a4Ds6wdfKDnfDUbD4C 3J+nRBSW2wZ/MO3aXS3KwltTOCbrsdyzFlJGrxGZYyQX+RcTP8jEbPV0Kx6591hqGjtW SUmPY0rQaUV15XBDbgljuEsTb6kH4gIrFIAUxogGvjYJAM25zOfQqq9lxa9q650Rgg8m yWIgKta9OLGqQ8sNYouCs2H1qhMVAHnnChtXFH4fCSujVaoKHX/12uNqNDthZZAaEW2H wgig== X-Gm-Message-State: AC+VfDwjzxpuXvptsA+k2aVdYkAPHzwjX/BXPTHda4RBucQX7S+lZiPP r6Lz183Enq+AnU8Do9gDy5dW3A== X-Google-Smtp-Source: ACHHUZ4FqLn8QWNKwqXBi93vrruT9FCt4VR8KVinpAq4kslwjjH7GnGdirsqupXNVea819//36CFrQ== X-Received: by 2002:adf:dbc7:0:b0:306:3352:5b8c with SMTP id e7-20020adfdbc7000000b0030633525b8cmr8948912wrj.7.1684773077795; Mon, 22 May 2023 09:31:17 -0700 (PDT) Received: from localhost.localdomain ([2a01:e0a:28d:66d0:72d:52cc:8221:fcda]) by smtp.gmail.com with ESMTPSA id y10-20020adff6ca000000b002f103ca90cdsm8152677wrp.101.2023.05.22.09.31.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 May 2023 09:31:17 -0700 (PDT) From: Esteban Blanc To: linus.walleij@linaro.org, lgirdwood@gmail.com, broonie@kernel.org, a.zummo@towertech.it, alexandre.belloni@bootlin.com Cc: linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org, linux-rtc@vger.kernel.org, jpanis@baylibre.com, jneanne@baylibre.com, aseketeli@baylibre.com, eblanc@baylibre.com, u-kumar1@ti.com Subject: [PATCH v5 1/3] rtc: tps6594: Add driver for TPS6594 RTC Date: Mon, 22 May 2023 18:31:13 +0200 Message-Id: <20230522163115.2592883-2-eblanc@baylibre.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230522163115.2592883-1-eblanc@baylibre.com> References: <20230522163115.2592883-1-eblanc@baylibre.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org TPS6594 PMIC is a MFD. This patch adds support for the RTC found inside TPS6594 family of PMIC. Alarm is also supported. Signed-off-by: Esteban Blanc --- drivers/rtc/Kconfig | 12 + drivers/rtc/Makefile | 1 + drivers/rtc/rtc-tps6594.c | 463 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 476 insertions(+) create mode 100644 drivers/rtc/rtc-tps6594.c diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index 753872408615..0fc10710647a 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -578,6 +578,18 @@ config RTC_DRV_TPS6586X along with alarm. This driver supports the RTC driver for the TPS6586X RTC module. +config RTC_DRV_TPS6594 + tristate "TI TPS6594 RTC driver" + depends on MFD_TPS6594 + default MFD_TPS6594 + help + TI Power Management IC TPS6594 supports RTC functionality + along with alarm. This driver supports the RTC driver for + the TPS6594 RTC module. + + This driver can also be built as a module. If so, the module + will be called tps6594-rtc + config RTC_DRV_TPS65910 tristate "TI TPS65910 RTC driver" depends on MFD_TPS65910 diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index ea445d1ebb17..3d3f8c9d0697 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -175,6 +175,7 @@ obj-$(CONFIG_RTC_DRV_TEGRA) += rtc-tegra.o obj-$(CONFIG_RTC_DRV_TEST) += rtc-test.o obj-$(CONFIG_RTC_DRV_TI_K3) += rtc-ti-k3.o obj-$(CONFIG_RTC_DRV_TPS6586X) += rtc-tps6586x.o +obj-$(CONFIG_RTC_DRV_TPS6594) += rtc-tps6594.o obj-$(CONFIG_RTC_DRV_TPS65910) += rtc-tps65910.o obj-$(CONFIG_RTC_DRV_TWL4030) += rtc-twl.o obj-$(CONFIG_RTC_DRV_VT8500) += rtc-vt8500.o diff --git a/drivers/rtc/rtc-tps6594.c b/drivers/rtc/rtc-tps6594.c new file mode 100644 index 000000000000..a91f7b546e07 --- /dev/null +++ b/drivers/rtc/rtc-tps6594.c @@ -0,0 +1,463 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * RTC driver for tps6594 PMIC + * + * Copyright (C) 2023 BayLibre Incorporated - https://www.baylibre.com/ + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define TPS6594_GET_TIME_ON TPS6594_BIT_GET_TIME +#define TPS6594_GET_TIME_OFF 0 +#define TPS6594_IT_ALARM_ON TPS6594_BIT_IT_ALARM +#define TPS6594_IT_ALARM_OFF 0 +#define TPS6594_AUTO_COMP_ON TPS6594_BIT_IT_ALARM + +// Total number of RTC registers needed to set time +#define NUM_TIME_REGS (TPS6594_REG_RTC_WEEKS - TPS6594_REG_RTC_SECONDS + 1) + +// Total number of RTC alarm registers +#define NUM_TIME_ALARM_REGS (NUM_TIME_REGS - 1) + +// Total number of RTC registers needed to set compensation registers +#define NUM_COMP_REGS (TPS6594_REG_RTC_COMP_MSB - TPS6594_REG_RTC_COMP_LSB + 1) + +/* + * Min and max values supported by 'offset' interface (swapped sign). + * After conversion, the values do not exceed the range [-32767, 33767] + * which COMP_REG must conform to. + */ +#define MIN_OFFSET (-277774) +#define MAX_OFFSET (277774) + +// Number of ticks per hour +#define TICKS_PER_HOUR (32768 * 3600) + +// Multiplier for ppb conversions +#define PPB_MULT NANO + +static int tps6594_rtc_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct tps6594 *tps = dev_get_drvdata(dev->parent); + u8 val = 0; + + val = enabled ? TPS6594_IT_ALARM_ON : TPS6594_IT_ALARM_OFF; + + return regmap_update_bits(tps->regmap, TPS6594_REG_RTC_INTERRUPTS, + TPS6594_BIT_IT_ALARM, val); +} + +/* Pulse GET_TIME field of RTC_CTRL_1 to store a timestamp in shadow registers. */ +static int tps6594_rtc_shadow_timestamp(struct device *dev, struct tps6594 *tps) +{ + int ret; + + /* + * Set GET_TIME to 0. Next time we set GET_TIME to 1 we will be sure to store + * an up-to-date timestamp. + */ + ret = regmap_clear_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1, + TPS6594_BIT_GET_TIME); + if (ret < 0) + return ret; + + /* + * Copy content of RTC registers to shadow registers or latches to read + * a coherent timestamp. + */ + return regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1, + TPS6594_BIT_GET_TIME); +} + +static int tps6594_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + unsigned char rtc_data[NUM_TIME_REGS]; + struct tps6594 *tps = dev_get_drvdata(dev->parent); + int ret; + + // Check if RTC is running. + ret = regmap_test_bits(tps->regmap, TPS6594_REG_RTC_STATUS, + TPS6594_BIT_RUN); + if (ret < 0) + return ret; + if (ret == 0) + return -EINVAL; + + ret = tps6594_rtc_shadow_timestamp(dev, tps); + if (ret < 0) + return ret; + + // Read shadowed RTC registers. + ret = regmap_bulk_read(tps->regmap, TPS6594_REG_RTC_SECONDS, rtc_data, + NUM_TIME_REGS); + if (ret < 0) + return ret; + + tm->tm_sec = bcd2bin(rtc_data[0]); + tm->tm_min = bcd2bin(rtc_data[1]); + tm->tm_hour = bcd2bin(rtc_data[2]); + tm->tm_mday = bcd2bin(rtc_data[3]); + tm->tm_mon = bcd2bin(rtc_data[4]) - 1; + tm->tm_year = bcd2bin(rtc_data[5]) + 100; + tm->tm_wday = bcd2bin(rtc_data[6]); + + return ret; +} + +static int tps6594_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + unsigned char rtc_data[NUM_TIME_REGS]; + struct tps6594 *tps = dev_get_drvdata(dev->parent); + int ret; + + rtc_data[0] = bin2bcd(tm->tm_sec); + rtc_data[1] = bin2bcd(tm->tm_min); + rtc_data[2] = bin2bcd(tm->tm_hour); + rtc_data[3] = bin2bcd(tm->tm_mday); + rtc_data[4] = bin2bcd(tm->tm_mon + 1); + rtc_data[5] = bin2bcd(tm->tm_year - 100); + rtc_data[6] = bin2bcd(tm->tm_wday); + + // Stop RTC while updating the RTC time registers. + ret = regmap_clear_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1, + TPS6594_BIT_STOP_RTC); + if (ret < 0) + return ret; + + // Update all the time registers in one shot. + ret = regmap_bulk_write(tps->regmap, TPS6594_REG_RTC_SECONDS, rtc_data, + NUM_TIME_REGS); + if (ret < 0) + return ret; + + // Start back RTC. + return regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1, + TPS6594_BIT_STOP_RTC); +} + +static int tps6594_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) +{ + unsigned char alarm_data[NUM_TIME_ALARM_REGS]; + u32 int_val; + struct tps6594 *tps = dev_get_drvdata(dev->parent); + int ret; + + ret = regmap_bulk_read(tps->regmap, TPS6594_REG_ALARM_SECONDS, + alarm_data, NUM_TIME_ALARM_REGS); + if (ret < 0) + return ret; + + alm->time.tm_sec = bcd2bin(alarm_data[0]); + alm->time.tm_min = bcd2bin(alarm_data[1]); + alm->time.tm_hour = bcd2bin(alarm_data[2]); + alm->time.tm_mday = bcd2bin(alarm_data[3]); + alm->time.tm_mon = bcd2bin(alarm_data[4]) - 1; + alm->time.tm_year = bcd2bin(alarm_data[5]) + 100; + + ret = regmap_read(tps->regmap, TPS6594_REG_RTC_INTERRUPTS, &int_val); + if (ret < 0) + return ret; + + alm->enabled = int_val & TPS6594_BIT_IT_ALARM; + + return 0; +} + +static int tps6594_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) +{ + unsigned char alarm_data[NUM_TIME_ALARM_REGS]; + struct tps6594 *tps = dev_get_drvdata(dev->parent); + int ret; + + // Disable alarm irq before changing the alarm timestamp. + ret = tps6594_rtc_alarm_irq_enable(dev, 0); + if (ret) + return ret; + + alarm_data[0] = bin2bcd(alm->time.tm_sec); + alarm_data[1] = bin2bcd(alm->time.tm_min); + alarm_data[2] = bin2bcd(alm->time.tm_hour); + alarm_data[3] = bin2bcd(alm->time.tm_mday); + alarm_data[4] = bin2bcd(alm->time.tm_mon + 1); + alarm_data[5] = bin2bcd(alm->time.tm_year - 100); + + // Update all the alarm registers in one shot. + ret = regmap_bulk_write(tps->regmap, TPS6594_REG_ALARM_SECONDS, + alarm_data, NUM_TIME_ALARM_REGS); + if (ret < 0) + return ret; + + if (alm->enabled) + ret = tps6594_rtc_alarm_irq_enable(dev, 1); + + return ret; +} + +static int tps6594_rtc_set_calibration(struct device *dev, int calibration) +{ + unsigned char comp_data[NUM_COMP_REGS]; + struct tps6594 *tps = dev_get_drvdata(dev->parent); + __le16 value; + int ret; + + /* + * TPS6594 uses two's complement 16 bit value for compensation of RTC + * crystal inaccuracies. One time every hour when seconds counter + * increments from 0 to 1 compensation value will be added to internal + * RTC counter value. + * + * Valid range for compensation value: [-32767 .. 32767]. + */ + if (calibration < -32767 || calibration > 32767) { + dev_err(dev, "RTC calibration value out of range: %d\n", + calibration); + return -EINVAL; + } + + value = (__le16)calibration; + + comp_data[0] = value & 0xFF; + comp_data[1] = (value >> 8) & 0xFF; + + // Update all the compensation registers in one shot. + ret = regmap_bulk_write(tps->regmap, TPS6594_REG_RTC_COMP_LSB, + comp_data, NUM_COMP_REGS); + if (ret < 0) + return ret; + + // Enable automatic compensation. + return regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1, + TPS6594_BIT_AUTO_COMP); +} + +static int tps6594_rtc_get_calibration(struct device *dev, int *calibration) +{ + unsigned char comp_data[NUM_COMP_REGS]; + struct tps6594 *tps = dev_get_drvdata(dev->parent); + unsigned int ctrl; + __le16 value; + int ret; + + ret = regmap_read(tps->regmap, TPS6594_REG_RTC_CTRL_1, &ctrl); + if (ret < 0) + return ret; + + // If automatic compensation is not enabled report back zero. + if (!(ctrl & TPS6594_BIT_AUTO_COMP)) { + *calibration = 0; + return 0; + } + + ret = regmap_bulk_read(tps->regmap, TPS6594_REG_RTC_COMP_LSB, comp_data, + NUM_COMP_REGS); + if (ret < 0) + return ret; + + value = (__le16)comp_data[0] | ((__le16)comp_data[1] << 8); + + *calibration = value; + + return 0; +} + +static int tps6594_rtc_read_offset(struct device *dev, long *offset) +{ + int calibration; + s64 tmp; + int ret; + + ret = tps6594_rtc_get_calibration(dev, &calibration); + if (ret < 0) + return ret; + + // Convert from RTC calibration register format to ppb format. + tmp = calibration * PPB_MULT; + + if (tmp < 0) + tmp -= TICKS_PER_HOUR / 2LL; + else + tmp += TICKS_PER_HOUR / 2LL; + tmp = div_s64(tmp, TICKS_PER_HOUR); + + /* + * SAFETY: + * Compution is the reverse operation of the one done in + * `tps6594_rtc_set_offset`. The safety remarks applie here too. + */ + + /* + * Offset value operates in negative way, so swap sign. + * See 8.3.10.5, (32768 - COMP_REG). + */ + *offset = (long)-tmp; + + return 0; +} + +static int tps6594_rtc_set_offset(struct device *dev, long offset) +{ + int calibration; + s64 tmp; + + // Make sure offset value is within supported range. + if (offset < MIN_OFFSET || offset > MAX_OFFSET) + return -ERANGE; + + // Convert from ppb format to RTC calibration register format. + + tmp = offset * TICKS_PER_HOUR; + if (tmp < 0) + tmp -= PPB_MULT / 2LL; + else + tmp += PPB_MULT / 2LL; + tmp = div_s64(tmp, PPB_MULT); + + /* + * SAFETY: + * - tmp = offset * TICK_PER_HOUR : + * `offset` can't be more than 277774, so `tmp` can't exceed 277774000000000 + * which is lower than the maximum value in an `s64` (2^63-1). No overflow here. + * + * - tmp += TICK_PER_HOUR / 2LL : + * tmp will have a maximum value of 277774117964800 which is still inferior to 2^63-1. + */ + + // Offset value operates in negative way, so swap sign. + calibration = (int)-tmp; + + return tps6594_rtc_set_calibration(dev, calibration); +} + +static irqreturn_t tps6594_rtc_interrupt(int irq, void *rtc) +{ + struct device *dev = rtc; + unsigned long events = 0; + struct tps6594 *tps = dev_get_drvdata(dev->parent); + struct rtc_device *rtc_dev = dev_get_drvdata(dev); + int ret; + u32 rtc_reg; + + ret = regmap_read(tps->regmap, TPS6594_REG_RTC_STATUS, &rtc_reg); + if (ret) + return IRQ_NONE; + + if (rtc_reg & TPS6594_BIT_ALARM) + events = RTC_IRQF | RTC_AF; + + // Notify RTC core on event. + rtc_update_irq(rtc_dev, 1, events); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops tps6594_rtc_ops = { + .read_time = tps6594_rtc_read_time, + .set_time = tps6594_rtc_set_time, + .read_alarm = tps6594_rtc_read_alarm, + .set_alarm = tps6594_rtc_set_alarm, + .alarm_irq_enable = tps6594_rtc_alarm_irq_enable, + .read_offset = tps6594_rtc_read_offset, + .set_offset = tps6594_rtc_set_offset, +}; + +static int tps6594_rtc_probe(struct platform_device *pdev) +{ + struct tps6594 *tps = dev_get_drvdata(pdev->dev.parent); + struct rtc_device *rtc; + int irq; + int ret; + + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); + if (!rtc) + return -ENOMEM; + + rtc = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + // Enable crystal oscillator. + ret = regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_2, + TPS6594_BIT_XTAL_EN); + if (ret < 0) + return ret; + + ret = regmap_test_bits(tps->regmap, TPS6594_REG_RTC_STATUS, + TPS6594_BIT_RUN); + if (ret < 0) + return ret; + // RTC not running. + if (ret == 0) { + ret = regmap_set_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1, + TPS6594_BIT_STOP_RTC); + if (ret < 0) + return ret; + + /* + * RTC should be running now. Check if this is the case. + * If not it might be a missing oscillator. + */ + ret = regmap_test_bits(tps->regmap, TPS6594_REG_RTC_STATUS, + TPS6594_BIT_RUN); + if (ret < 0) + return ret; + if (ret == 0) + return -ENODEV; + + // Stop RTC until first call to `tps6594_rtc_set_time`. + ret = regmap_clear_bits(tps->regmap, TPS6594_REG_RTC_CTRL_1, + TPS6594_BIT_STOP_RTC); + if (ret < 0) + return ret; + } + + platform_set_drvdata(pdev, rtc); + + irq = platform_get_irq_byname(pdev, TPS6594_IRQ_NAME_ALARM); + if (irq < 0) + return dev_err_probe(&pdev->dev, irq, "Failed to get irq\n"); + + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, + tps6594_rtc_interrupt, IRQF_ONESHOT, + TPS6594_IRQ_NAME_ALARM, &pdev->dev); + if (ret < 0) + return dev_err_probe(&pdev->dev, ret, + "Failed to request_threaded_irq\n"); + + ret = device_init_wakeup(&pdev->dev, true); + if (ret < 0) + return dev_err_probe(&pdev->dev, ret, + "Failed to init rtc as wakeup source\n"); + + rtc->ops = &tps6594_rtc_ops; + rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; + rtc->range_max = RTC_TIMESTAMP_END_2099; + + return devm_rtc_register_device(rtc); +} + +static struct platform_driver tps6594_rtc_driver = { + .probe = tps6594_rtc_probe, + .driver = { + .name = "tps6594-rtc", + }, +}; + +module_platform_driver(tps6594_rtc_driver); +MODULE_ALIAS("platform:rtc-tps6594-rtc"); +MODULE_AUTHOR("Esteban Blanc "); +MODULE_DESCRIPTION("TPS6594 RTC driver"); +MODULE_LICENSE("GPL");