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authorLinus Torvalds <torvalds@linux-foundation.org>2021-04-28 15:59:13 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-04-28 15:59:13 -0700
commit71a5cc28e88b0db69c3f83d4061ad4cc684af09f (patch)
tree3cc40d902e7cba992c27c946f69ef65fc7d2a807 /drivers/rtc/rtc-ntxec.c
parentbe18cd1fcae2ed7db58d92d20733dfa8aa0a5173 (diff)
parentf9386c91574fe6da9f4fca9a47734816b0db0019 (diff)
Merge tag 'mfd-next-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
Pull MFD updates from Lee Jones: "Core Framework: - Add support for Software Nodes to MFD Core - Remove support for Device Properties from MFD Core - Use standard APIs in MFD Core New Drivers: - Add support for ROHM BD9576MUF and BD9573MUF PMICs - Add support for Netronix Embedded Controller, PWM and RTC - Add support for Actions Semi ATC260x PMICs and OnKey New Device Support: - Add support for DG1 PCIe Graphics Card to Intel PMT - Add support for ROHM BD71815 PMIC to ROHM BD71828 - Add support for Tolino Shine 2 HD to Netronix Embedded Controller - Add support for AX10 BMC Secure Updates to Intel M10 BMC Removed Device Support: - Remove Arizona Extcon support from MFD - Remove ST-E AB8500 Power Supply code from MFD - Remove AB3100 altogether New Functionality: - Add support for SMBus and I2C modes to Dialog DA9063 - Switch to using Software Nodes in Intel (various) New/converted Device Tree bindings: - rohm bd71815-pmic, rohm bd9576-pmic, netronix ntxec, actions atc260x, ricoh rn5t618, qcom pm8xxx - Fix-ups: - Fix error handling/path; intel_pmt - Simplify code; rohm-bd718x7, ab8500-core, intel-m10-bmc - Trivial clean-ups (reordering, spelling); rohm-generic, rn5t618, max8997 - Use correct data-type; db8500-prcmu - Remove superfluous code; lp87565, intel_quark_i2c_gpi, lpc_sch, twl - Use generic APIs/defines; lm3533-core, intel_quark_i2c_gpio - Regmap related fix-ups; intel-m10-bmc, sec-core - Reorder resource freeing during remove; intel_quark_i2c_gpio - Make table indexing more robust; intel_quark_i2c_gpio - Fix reference imbalances; arizona-irq - Staticify and (un)constify things; arizona-spi, stmpe, ene-kb3930, intel-lpss-acpi, intel-lpss-pci, atc260x-i2c, intel_quark_i2c_gpio Bug Fixes: - Fix incorrect (register) values; intel-m10-bmc - Kconfig related fixes; ABX500_CORE - Do not clear the Auto Reload Register; stm32-timers" * tag 'mfd-next-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (84 commits) mfd: intel-m10-bmc: Add support for MAX10 BMC Secure Updates Revert "mfd: max8997: Add of_compatible to Extcon and Charger mfd_cell" mfd: twl: Remove unused inline function twl4030charger_usb_en() dt-bindings: mfd: Convert pm8xxx bindings to yaml dt-bindings: mfd: Add compatible for pmk8350 rtc i2c: designware: Get rid of legacy platform data mfd: intel_quark_i2c_gpio: Convert I²C to use software nodes mfd: lpc_sch: Partially revert "Add support for Intel Quark X1000" mfd: arizona: Fix rumtime PM imbalance on error mfd: max8997: Replace 8998 with 8997 mfd: core: Use acpi_find_child_device() for child devices lookup mfd: intel_quark_i2c_gpio: Don't play dirty trick with const mfd: intel_quark_i2c_gpio: Enable MSI interrupt mfd: intel_quark_i2c_gpio: Reuse BAR definitions for MFD cell indexing mfd: ntxec: Support for EC in Tolino Shine 2 HD mfd: stm32-timers: Avoid clearing auto reload register mfd: intel_quark_i2c_gpio: Replace I²C speeds with descriptive definitions mfd: intel_quark_i2c_gpio: Remove unused struct device member mfd: intel_quark_i2c_gpio: Unregister resources in reversed order mfd: Kconfig: ABX500_CORE should depend on ARCH_U8500 ...
Diffstat (limited to 'drivers/rtc/rtc-ntxec.c')
-rw-r--r--drivers/rtc/rtc-ntxec.c145
1 files changed, 145 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ntxec.c b/drivers/rtc/rtc-ntxec.c
new file mode 100644
index 000000000000..850ca49186fd
--- /dev/null
+++ b/drivers/rtc/rtc-ntxec.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * The Netronix embedded controller is a microcontroller found in some
+ * e-book readers designed by the original design manufacturer Netronix, Inc.
+ * It contains RTC, battery monitoring, system power management, and PWM
+ * functionality.
+ *
+ * This driver implements access to the RTC time and date.
+ *
+ * Copyright 2020 Jonathan Neuschäfer <j.neuschaefer@gmx.net>
+ */
+
+#include <linux/mfd/ntxec.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/rtc.h>
+#include <linux/types.h>
+
+struct ntxec_rtc {
+ struct device *dev;
+ struct ntxec *ec;
+};
+
+#define NTXEC_REG_WRITE_YEAR 0x10
+#define NTXEC_REG_WRITE_MONTH 0x11
+#define NTXEC_REG_WRITE_DAY 0x12
+#define NTXEC_REG_WRITE_HOUR 0x13
+#define NTXEC_REG_WRITE_MINUTE 0x14
+#define NTXEC_REG_WRITE_SECOND 0x15
+
+#define NTXEC_REG_READ_YEAR_MONTH 0x20
+#define NTXEC_REG_READ_MDAY_HOUR 0x21
+#define NTXEC_REG_READ_MINUTE_SECOND 0x23
+
+static int ntxec_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ntxec_rtc *rtc = dev_get_drvdata(dev);
+ unsigned int value;
+ int res;
+
+retry:
+ res = regmap_read(rtc->ec->regmap, NTXEC_REG_READ_MINUTE_SECOND, &value);
+ if (res < 0)
+ return res;
+
+ tm->tm_min = value >> 8;
+ tm->tm_sec = value & 0xff;
+
+ res = regmap_read(rtc->ec->regmap, NTXEC_REG_READ_MDAY_HOUR, &value);
+ if (res < 0)
+ return res;
+
+ tm->tm_mday = value >> 8;
+ tm->tm_hour = value & 0xff;
+
+ res = regmap_read(rtc->ec->regmap, NTXEC_REG_READ_YEAR_MONTH, &value);
+ if (res < 0)
+ return res;
+
+ tm->tm_year = (value >> 8) + 100;
+ tm->tm_mon = (value & 0xff) - 1;
+
+ /*
+ * Read the minutes/seconds field again. If it changed since the first
+ * read, we can't assume that the values read so far are consistent,
+ * and should start from the beginning.
+ */
+ res = regmap_read(rtc->ec->regmap, NTXEC_REG_READ_MINUTE_SECOND, &value);
+ if (res < 0)
+ return res;
+
+ if (tm->tm_min != value >> 8 || tm->tm_sec != (value & 0xff))
+ goto retry;
+
+ return 0;
+}
+
+static int ntxec_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct ntxec_rtc *rtc = dev_get_drvdata(dev);
+
+ /*
+ * To avoid time overflows while we're writing the full date/time,
+ * set the seconds field to zero before doing anything else. For the
+ * next 59 seconds (plus however long it takes until the RTC's next
+ * update of the second field), the seconds field will not overflow
+ * into the other fields.
+ */
+ struct reg_sequence regs[] = {
+ { NTXEC_REG_WRITE_SECOND, ntxec_reg8(0) },
+ { NTXEC_REG_WRITE_YEAR, ntxec_reg8(tm->tm_year - 100) },
+ { NTXEC_REG_WRITE_MONTH, ntxec_reg8(tm->tm_mon + 1) },
+ { NTXEC_REG_WRITE_DAY, ntxec_reg8(tm->tm_mday) },
+ { NTXEC_REG_WRITE_HOUR, ntxec_reg8(tm->tm_hour) },
+ { NTXEC_REG_WRITE_MINUTE, ntxec_reg8(tm->tm_min) },
+ { NTXEC_REG_WRITE_SECOND, ntxec_reg8(tm->tm_sec) },
+ };
+
+ return regmap_multi_reg_write(rtc->ec->regmap, regs, ARRAY_SIZE(regs));
+}
+
+static const struct rtc_class_ops ntxec_rtc_ops = {
+ .read_time = ntxec_read_time,
+ .set_time = ntxec_set_time,
+};
+
+static int ntxec_rtc_probe(struct platform_device *pdev)
+{
+ struct rtc_device *dev;
+ struct ntxec_rtc *rtc;
+
+ pdev->dev.of_node = pdev->dev.parent->of_node;
+
+ rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
+ rtc->dev = &pdev->dev;
+ rtc->ec = dev_get_drvdata(pdev->dev.parent);
+ platform_set_drvdata(pdev, rtc);
+
+ dev = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(dev))
+ return PTR_ERR(dev);
+
+ dev->ops = &ntxec_rtc_ops;
+ dev->range_min = RTC_TIMESTAMP_BEGIN_2000;
+ dev->range_max = 9025257599LL; /* 2255-12-31 23:59:59 */
+
+ return devm_rtc_register_device(dev);
+}
+
+static struct platform_driver ntxec_rtc_driver = {
+ .driver = {
+ .name = "ntxec-rtc",
+ },
+ .probe = ntxec_rtc_probe,
+};
+module_platform_driver(ntxec_rtc_driver);
+
+MODULE_AUTHOR("Jonathan Neuschäfer <j.neuschaefer@gmx.net>");
+MODULE_DESCRIPTION("RTC driver for Netronix EC");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ntxec-rtc");