From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752249AbeEPVI7 (ORCPT ); Wed, 16 May 2018 17:08:59 -0400 Received: from mail.micronovasrl.com ([212.103.203.10]:55354 "EHLO mail.micronovasrl.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752201AbeEPVI4 (ORCPT ); Wed, 16 May 2018 17:08:56 -0400 Authentication-Results: mail.micronovasrl.com (amavisd-new); dkim=pass reason="pass (just generated, assumed good)" header.d=micronovasrl.com X-Spam-Flag: NO X-Spam-Score: -2.9 From: Giulio Benetti To: a.zummo@towertech.it, alexandre.belloni@bootlin.com Cc: robh+dt@kernel.org, mark.rutland@arm.com, linux-rtc@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, andy.shevchenko@gmail.com, Giulio Benetti Subject: [PATCH v6 4/4] rtc: ds1307: add frequency_test_enable sysfs attribute to check tick on m41txx Date: Wed, 16 May 2018 23:08:42 +0200 Message-Id: <20180516210842.5874-4-giulio.benetti@micronovasrl.com> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180516210842.5874-1-giulio.benetti@micronovasrl.com> References: <20180516210842.5874-1-giulio.benetti@micronovasrl.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On m41txx you can enable open-drain OUT pin to check if offset is ok. Enabling OUT pin with frequency_test_enable attribute, OUT pin will tick 512 times faster than 1s tick base. Enable or Disable FT bit on CONTROL register if freq_test is 1 or 0. Signed-off-by: Giulio Benetti --- V5 => V6 * frequency_test_enable handled as a boolean drivers/rtc/rtc-ds1307.c | 96 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 96 insertions(+) diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c index 2797d01bfa1d..b2e87845d860 100644 --- a/drivers/rtc/rtc-ds1307.c +++ b/drivers/rtc/rtc-ds1307.c @@ -1053,6 +1053,96 @@ static int m41txx_rtc_set_offset(struct device *dev, long offset) ctrl_reg); } +static ssize_t frequency_test_enable_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct ds1307 *ds1307 = dev_get_drvdata(dev); + bool freq_test_en = 0; + int ret; + + ret = kstrtobool(buf, &freq_test_en); + if (ret == -EINVAL) { + dev_err(dev, "Failed to store RTC Frequency Test attribute\n"); + return ret; + } + + regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, M41TXX_BIT_FT, + freq_test_en ? M41TXX_BIT_FT : 0); + + return count; +} + +static ssize_t frequency_test_enable_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct ds1307 *ds1307 = dev_get_drvdata(dev); + unsigned int ctrl_reg; + + regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg); + + if (ctrl_reg & M41TXX_BIT_FT) + return scnprintf(buf, PAGE_SIZE, "on\n"); + else + return scnprintf(buf, PAGE_SIZE, "off\n"); +} + +static DEVICE_ATTR_RW(frequency_test_enable); + +static struct attribute *rtc_freq_test_attrs[] = { + &dev_attr_frequency_test_enable.attr, + NULL, +}; + +static const struct attribute_group rtc_freq_test_attr_group = { + .attrs = rtc_freq_test_attrs, +}; + +static void rtc_calib_remove_sysfs_group(void *_dev) +{ + struct device *dev = _dev; + + sysfs_remove_group(&dev->kobj, &rtc_freq_test_attr_group); +} + +static int ds1307_add_frequency_test(struct ds1307 *ds1307) +{ + int err = 0; + + switch (ds1307->type) { + case m41t0: + case m41t00: + case m41t11: + /* Export sysfs entries */ + err = sysfs_create_group(&(ds1307->dev)->kobj, + &rtc_freq_test_attr_group); + if (err) { + dev_err(ds1307->dev, + "Failed to create sysfs group: %d\n", + err); + return err; + } + + err = devm_add_action_or_reset(ds1307->dev, + rtc_calib_remove_sysfs_group, + ds1307->dev); + if (err) { + dev_err(ds1307->dev, + "Failed to add sysfs cleanup action: %d\n", + err); + sysfs_remove_group(&(ds1307->dev)->kobj, + &rtc_freq_test_attr_group); + return err; + } + break; + default: + break; + } + + return err; +} + /*----------------------------------------------------------------------*/ static int ds1307_nvram_read(void *priv, unsigned int offset, void *val, @@ -1794,6 +1884,12 @@ static int ds1307_probe(struct i2c_client *client, if (err) return err; + err = ds1307_add_frequency_test(ds1307); + if (err) { + rtc_device_unregister(ds1307->rtc); + return err; + } + if (chip->nvram_size) { struct nvmem_config nvmem_cfg = { .name = "ds1307_nvram", -- 2.17.0