On Mon, Dec 16, 2013 at 10:17:47PM +0100, Arnaud Ebalard wrote: > > Intersil ISL12057 I2C RTC chip also supports two alarms. This patch > only adds support for basic RTC functionalities (i.e. getting and > setting time). Tests have been performed on NETGEAR ReadyNAS 102 w/ > startup/shutdown scripts, hwclock, ntpdate and openntpd. > > Signed-off-by: Arnaud Ebalard <arno@xxxxxxxxxxxx> Weird; I saved the patch again and the '=3D' is gone. Maybe it was PBKC. Comments inline. > --- > > In order to get at least some initial support for the chip available in > mainline kernel (v3.14 will have three users waiting for it: ReadyNAS > 102, 104 and 2120), I decided to temporarily remove the alarm and IRQ > related code I pushed earlier (see [1] below). If possible, I'd like to > iterate on this before Christmas in order not to miss ARM submission > cutoff (around -rc5) to push the .dts changes (once the driver is queued > for 3.14). > > I will submit a patch later to add back Alarm/IRQ support once I get > some understanding of how to correctly handle my use case in current > RTC subsystem logic. > > Comments welcome! > > Cheers, > > a+ > > [1]: http://thread.gmane.org/gmane.linux.drivers.devicetree/46581 > > Changes since previous v3 (comments from Guenter Roeck): > - use BIT() instead of (1<<X) > - use dev_set_drvdata()/dev_get_drvdata() to simplify access to 'data' > - removed two (now) useless fields in private 'data' structure > - now use dev instead of &client->dev > > Changes since previous v2 (Comments from Mark Brown): > - converted to regmap > > Changes since previous v1 (Comments from Mark Rutland): > - fixed return values for isl12057_i2c_{read,set}_regs() > - checked associated return paths > > Changes since previous v0: > - removed alarm and IRQ related code > - Switched to isl for intersil (no existing driver has any reference > to isil, even though this would be the recommended choice) > - Added intersil info in vendor-prefixes.txt file > - Added entry for ISL 12057 in I2C trivial-devices.txt file > - Added mutex protection for non atomic read/write > > > .../devicetree/bindings/i2c/trivial-devices.txt | 1 + > .../devicetree/bindings/vendor-prefixes.txt | 1 + > drivers/rtc/Kconfig | 11 + > drivers/rtc/Makefile | 1 + > drivers/rtc/rtc-isl12057.c | 358 +++++++++++++++++++++ > 5 files changed, 372 insertions(+) > create mode 100644 drivers/rtc/rtc-isl12057.c > > diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt > index b1cb341..cdf1430 100644 > --- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt > +++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt > @@ -39,6 +39,7 @@ fsl,sgtl5000 SGTL5000: Ultra Low-Power Audio Codec > gmt,g751 G751: Digital Temperature Sensor and Thermal Watchdog with Two-Wire Interface > infineon,slb9635tt Infineon SLB9635 (Soft-) I2C TPM (old protocol, max 100khz) > infineon,slb9645tt Infineon SLB9645 I2C TPM (new protocol, max 400khz) > +isl,isl12057 Intersil ISL12057 I2C RTC Chip > maxim,ds1050 5 Bit Programmable, Pulse-Width Modulator > maxim,max1237 Low-Power, 4-/12-Channel, 2-Wire Serial, 12-Bit ADCs > maxim,max6625 9-Bit/12-Bit Temperature Sensors with I²C-Compatible Serial Interface > diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt > index edbb8d8..ed0f63f 100644 > --- a/Documentation/devicetree/bindings/vendor-prefixes.txt > +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt > @@ -39,6 +39,7 @@ ibm International Business Machines (IBM) > idt Integrated Device Technologies, Inc. > img Imagination Technologies Ltd. > intercontrol Inter Control Group > +isl Intersil > lg LG Corporation > linux Linux-specific binding > lsi LSI Corp. (LSI Logic) > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig > index 0077302..9608210 100644 > --- a/drivers/rtc/Kconfig > +++ b/drivers/rtc/Kconfig > @@ -304,6 +304,17 @@ config RTC_DRV_ISL12022 > This driver can also be built as a module. If so, the module > will be called rtc-isl12022. > > +config RTC_DRV_ISL12057 > + depends on I2C > + select REGMAP_I2C > + tristate "Intersil ISL12057" > + help > + If you say yes here you get support for the Intersil ISL12057 > + I2C RTC chip. > + > + This driver can also be built as a module. If so, the module > + will be called rtc-isl12057. > + > config RTC_DRV_X1205 > tristate "Xicor/Intersil X1205" > help > diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile > index 27b4bd8..6cd50e5 100644 > --- a/drivers/rtc/Makefile > +++ b/drivers/rtc/Makefile > @@ -58,6 +58,7 @@ obj-$(CONFIG_RTC_DRV_HID_SENSOR_TIME) += rtc-hid-sensor-time.o > obj-$(CONFIG_RTC_DRV_IMXDI) += rtc-imxdi.o > obj-$(CONFIG_RTC_DRV_ISL1208) += rtc-isl1208.o > obj-$(CONFIG_RTC_DRV_ISL12022) += rtc-isl12022.o > +obj-$(CONFIG_RTC_DRV_ISL12057) += rtc-isl12057.o Please use tab after the define. > obj-$(CONFIG_RTC_DRV_JZ4740) += rtc-jz4740.o > obj-$(CONFIG_RTC_DRV_LP8788) += rtc-lp8788.o > obj-$(CONFIG_RTC_DRV_LPC32XX) += rtc-lpc32xx.o > diff --git a/drivers/rtc/rtc-isl12057.c b/drivers/rtc/rtc-isl12057.c > new file mode 100644 > index 0000000..8a1851e > --- /dev/null > +++ b/drivers/rtc/rtc-isl12057.c > @@ -0,0 +1,358 @@ > +/* > + * rtc-isl12057 - Driver for Intersil ISL12057 I2C Real Time Clock > + * > + * Copyright (C) 2013, Arnaud EBALARD <arno@xxxxxxxxxxxx> > + * > + * This work is largely based on Intersil ISL1208 driver developed by > + * Hebert Valerio Riedel <hvr@xxxxxxx>. > + * > + * Detailed datasheet on which this development is based is available here: > + * > + * http://natisbad.org/NAS2/refs/ISL12057.pdf > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the Free Software > + * Foundation. checkpatch complains about the above paragraph. I would suggest to remove it. > + */ > + > +#include <linux/module.h> > +#include <linux/mutex.h> > +#include <linux/rtc.h> > +#include <linux/i2c.h> > +#include <linux/bcd.h> > +#include <linux/rtc.h> > +#include <linux/of.h> > +#include <linux/of_device.h> > +#include <linux/regmap.h> > + > +#define DRV_NAME "rtc-isl12057" > + > +/* RTC section */ > +#define ISL12057_REG_RTC_SC 0x00 /* Seconds */ > +#define ISL12057_REG_RTC_MN 0x01 /* Minutes */ > +#define ISL12057_REG_RTC_HR 0x02 /* Hours */ > +#define ISL12057_REG_RTC_HR_PM BIT(5) /* AM/PM bit in 12h format */ > +#define ISL12057_REG_RTC_HR_MIL BIT(6) /* 24h/12h format */ > +#define ISL12057_REG_RTC_DW 0x03 /* Day of the Week */ > +#define ISL12057_REG_RTC_DT 0x04 /* Date */ > +#define ISL12057_REG_RTC_MO 0x05 /* Month */ > +#define ISL12057_REG_RTC_YR 0x06 /* Year */ > +#define ISL12057_RTC_SEC_LEN 7 > + > +/* Alarm 1 section */ > +#define ISL12057_REG_A1_SC 0x07 /* Alarm 1 Seconds */ > +#define ISL12057_REG_A1_MN 0x08 /* Alarm 1 Minutes */ > +#define ISL12057_REG_A1_HR 0x09 /* Alarm 1 Hours */ > +#define ISL12057_REG_A1_HR_PM BIT(5) /* AM/PM bit in 12h format */ > +#define ISL12057_REG_A1_HR_MIL BIT(6) /* 24h/12h format */ > +#define ISL12057_REG_A1_DWDT 0x0A /* Alarm 1 Date / Day of the week */ > +#define ISL12057_REG_A1_DWDT_B BIT(6) /* DW / DT selection bit */ > +#define ISL12057_A1_SEC_LEN 4 > + > +/* Alarm 2 section */ > +#define ISL12057_REG_A2_MN 0x0B /* Alarm 2 Minutes */ > +#define ISL12057_REG_A2_HR 0x0C /* Alarm 2 Hours */ > +#define ISL12057_REG_A2_DWDT 0x0D /* Alarm 2 Date / Day of the week */ > +#define ISL12057_A2_SEC_LEN 3 > + > +/* Control/Status registers */ > +#define ISL12057_REG_INT 0x0E > +#define ISL12057_REG_INT_A1IE BIT(0) /* Alarm 1 interrupt enable bit */ > +#define ISL12057_REG_INT_A2IE BIT(1) /* Alarm 2 interrupt enable bit */ > +#define ISL12057_REG_INT_INTCN BIT(2) /* Interrupt control enable bit */ > +#define ISL12057_REG_INT_RS1 BIT(3) /* Freq out control bit 1 */ > +#define ISL12057_REG_INT_RS2 BIT(4) /* Freq out control bit 2 */ > +#define ISL12057_REG_INT_EOSC BIT(7) /* Oscillator enable bit */ > + > +#define ISL12057_REG_SR 0x0F > +#define ISL12057_REG_SR_A1F BIT(0) /* Alarm 1 interrupt bit */ > +#define ISL12057_REG_SR_A2F BIT(1) /* Alarm 2 interrupt bit */ > +#define ISL12057_REG_SR_OSF BIT(7) /* Oscillator failure bit */ > + > +/* Register memory map length */ > +#define ISL12057_MEM_MAP_LEN 0x10 > + Please use tab after the define (and if possible before the comments). Also, many of the above defines are unused (especially the alarm defines). Will those ever be necessary/used ? Otherwise I would suggest to remove the unused defines. > +static struct i2c_driver isl12057_driver; > + Unnecessary. > +struct isl12057_rtc_data { > + struct rtc_device *rtc; > + struct regmap *regmap; > + struct mutex lock; > +}; > + > +static void isl12057_rtc_regs_to_tm(struct rtc_time *tm, u8 *regs) > +{ > + tm->tm_sec = bcd2bin(regs[ISL12057_REG_RTC_SC]); > + tm->tm_min = bcd2bin(regs[ISL12057_REG_RTC_MN]); > + > + if (regs[ISL12057_REG_RTC_HR] & ISL12057_REG_RTC_HR_MIL) { /* AM/PM */ > + tm->tm_hour = bcd2bin(regs[ISL12057_REG_RTC_HR] & 0x0f); > + if (regs[ISL12057_REG_RTC_HR] & ISL12057_REG_RTC_HR_PM) > + tm->tm_hour += 12; > + } else { /* 24 hour mode */ > + tm->tm_hour = bcd2bin(regs[ISL12057_REG_RTC_HR] & 0x3f); > + } > + > + tm->tm_mday = bcd2bin(regs[ISL12057_REG_RTC_DT]); > + tm->tm_wday = bcd2bin(regs[ISL12057_REG_RTC_DW]) - 1; /* starts at 1 */ > + tm->tm_mon = bcd2bin(regs[ISL12057_REG_RTC_MO]) - 1; /* starts at 1 */ > + tm->tm_year = bcd2bin(regs[ISL12057_REG_RTC_YR]) + 100; > +} > + > +static int isl12057_rtc_tm_to_regs(u8 *regs, struct rtc_time *tm) > +{ > + /* > + * The clock has an 8 bit wide bcd-coded register for the year. > + * tm_year is an offset from 1900 and we are interested in the > + * 2000-2099 range, so any value less than 100 is invalid. > + */ > + if (tm->tm_year < 100) > + return -EINVAL; > + > + regs[ISL12057_REG_RTC_SC] = bin2bcd(tm->tm_sec); > + regs[ISL12057_REG_RTC_MN] = bin2bcd(tm->tm_min); > + regs[ISL12057_REG_RTC_HR] = bin2bcd(tm->tm_hour); /* 24-hour format */ > + regs[ISL12057_REG_RTC_DT] = bin2bcd(tm->tm_mday); > + regs[ISL12057_REG_RTC_MO] = bin2bcd(tm->tm_mon + 1); > + regs[ISL12057_REG_RTC_YR] = bin2bcd(tm->tm_year - 100); > + regs[ISL12057_REG_RTC_DW] = bin2bcd(tm->tm_wday + 1); > + > + return 0; > +} > + > +/* > + * Try and match register bits w/ fixed null values to see whether we > + * are dealing with an ISL12057. > + */ For isl12057_check_rtc_status you added a comment explaining why a lock is not needed. It would be useful to have that same comment here as well. > +static int isl12057_i2c_validate_chip(struct regmap *regmap) > +{ > + u8 regs[ISL12057_MEM_MAP_LEN]; > + u8 mask[ISL12057_MEM_MAP_LEN] = { 0x80, 0x80, 0x80, 0xf8, > + 0xc0, 0x60, 0x00, 0x00, > + 0x00, 0x00, 0x00, 0x00, > + 0x00, 0x00, 0x60, 0x7c }; > + int ret, i; > + > + ret = regmap_bulk_read(regmap, 0, regs, ISL12057_MEM_MAP_LEN); > + if (ret) > + return ret; > + > + for (i = 0; i < ISL12057_MEM_MAP_LEN; ++i) { > + if (regs[i] & mask[i]) /* check if bits are cleared */ > + return -ENODEV; > + } > + > + return 0; > +} > + > +static int isl12057_rtc_read_time(struct device *dev, struct rtc_time *tm) > +{ > + struct isl12057_rtc_data *data = dev_get_drvdata(dev); > + u8 regs[ISL12057_RTC_SEC_LEN]; > + int ret; > + > + mutex_lock(&data->lock); > + ret = regmap_bulk_read(data->regmap, ISL12057_REG_RTC_SC, regs, > + ISL12057_RTC_SEC_LEN); > + mutex_unlock(&data->lock); > + > + if (ret) { > + dev_err(dev, "%s: RTC read failed\n", __func__); > + return ret; > + } > + > + isl12057_rtc_regs_to_tm(tm, regs); > + > + return rtc_valid_tm(tm); > +} > + > +static int isl12057_rtc_set_time(struct device *dev, struct rtc_time *tm) > +{ > + struct isl12057_rtc_data *data = dev_get_drvdata(dev); > + u8 regs[ISL12057_RTC_SEC_LEN]; > + int ret; > + > + ret = isl12057_rtc_tm_to_regs(regs, tm); > + if (ret) > + return ret; > + > + mutex_lock(&data->lock); > + ret = regmap_bulk_write(data->regmap, ISL12057_REG_RTC_SC, regs, > + ISL12057_RTC_SEC_LEN); > + mutex_unlock(&data->lock); > + > + if (ret) > + dev_err(dev, "%s: RTC write failed\n", __func__); > + > + return ret; > +} > + > +static int isl12057_rtc_proc(struct device *dev, struct seq_file *seq) > +{ > + struct isl12057_rtc_data *data = dev_get_drvdata(dev); > + int reg, ret; > + > + mutex_lock(&data->lock); > + > + /* Status register */ > + ret = regmap_read(data->regmap, ISL12057_REG_SR, ®); > + if (ret) { > + dev_err(dev, "%s: reading SR failed\n", __func__); > + goto out; > + } > + > + seq_printf(seq, "status_reg\t:%s%s%s (0x%.2x)\n", > + (reg & ISL12057_REG_SR_OSF) ? " OSF" : "", > + (reg & ISL12057_REG_SR_A1F) ? " A1F" : "", > + (reg & ISL12057_REG_SR_A2F) ? " A2F" : "", reg); > + > + /* Control register */ > + ret = regmap_read(data->regmap, ISL12057_REG_INT, ®); > + if (ret) { > + dev_err(dev, "%s: reading INT failed\n", __func__); > + goto out; > + } > + > + seq_printf(seq, "control_reg\t:%s%s%s%s%s%s (0x%.2x)\n", > + (reg & ISL12057_REG_INT_A1IE) ? " A1IE" : "", > + (reg & ISL12057_REG_INT_A2IE) ? " A2IE" : "", > + (reg & ISL12057_REG_INT_INTCN) ? " INTCN" : "", > + (reg & ISL12057_REG_INT_RS1) ? " RS1" : "", > + (reg & ISL12057_REG_INT_RS2) ? " RS2" : "", > + (reg & ISL12057_REG_INT_EOSC) ? " EOSC" : "", reg); > + > + out: > + mutex_unlock(&data->lock); > + > + return ret; > +} > + > +/* > + * Check current RTC status and enable/disable what needs to be. Return 0 if > + * everything went ok and a negative value upon error. Note: this function > + * is called early during init and hence does need mutex protection. > + */ > +static int isl12057_check_rtc_status(struct device *dev, struct regmap *regmap) > +{ > + int ret; > + > + /* Enable oscillator if not already running */ > + ret = regmap_update_bits(regmap, ISL12057_REG_INT, > + ISL12057_REG_INT_EOSC, 0); > + if (ret < 0) { > + dev_err(dev, "Enable to enable oscillator\n"); s/Enable/Unable/ or at least I think so. > + return ret; > + } > + > + /* Clear oscillator failure bit if needed */ > + ret = regmap_update_bits(regmap, ISL12057_REG_SR, > + ISL12057_REG_SR_OSF, 0); > + if (ret < 0) { > + dev_err(dev, "Enable to clear oscillator failure bit\n"); Unable ? > + return ret; > + } > + > + /* Clear alarm bit if needed */ > + ret = regmap_update_bits(regmap, ISL12057_REG_SR, > + ISL12057_REG_SR_A1F, 0); > + if (ret < 0) { > + dev_err(dev, "Enable to clear alarm bit\n"); Unable ? > + return ret; > + } > + > + return 0; > +} > + > +static const struct rtc_class_ops rtc_ops = { > + .read_time = isl12057_rtc_read_time, > + .set_time = isl12057_rtc_set_time, > + .proc = isl12057_rtc_proc, > +}; > + > +static struct regmap_config isl12057_rtc_regmap_config = { > + .reg_bits = 8, > + .val_bits = 8, > +}; > + > +static int isl12057_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct device *dev = &client->dev; > + struct isl12057_rtc_data *data; > + struct rtc_device *rtc; > + struct regmap *regmap; > + int ret; > + > + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C | > + I2C_FUNC_SMBUS_BYTE_DATA | > + I2C_FUNC_SMBUS_I2C_BLOCK)) > + return -ENODEV; > + > + regmap = devm_regmap_init_i2c(client, &isl12057_rtc_regmap_config); > + if (IS_ERR(regmap)) { > + ret = PTR_ERR(regmap); > + dev_err(dev, "regmap allocation failed: %d\n", ret); > + return ret; > + } > + > + ret = isl12057_i2c_validate_chip(regmap); > + if (ret) > + return ret; > + > + ret = isl12057_check_rtc_status(dev, regmap); > + if (ret) > + return ret; > + > + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + mutex_init(&data->lock); > + data->regmap = regmap; > + dev_set_drvdata(dev, data); > + > + rtc = devm_rtc_device_register(dev, DRV_NAME, &rtc_ops, THIS_MODULE); > + if (IS_ERR(rtc)) > + return PTR_ERR(rtc); > + data->rtc = rtc; data->rtc still seems to be unused. > + > + return 0; > +} > + > +#ifdef CONFIG_OF > +static struct of_device_id isl12057_dt_match[] = { > + { .compatible = "isl,isl12057" }, > + { }, > +}; > +#endif > + > +static const struct i2c_device_id isl12057_id[] = { > + { "isl12057", 0 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, isl12057_id); > + > +static struct i2c_driver isl12057_driver = { > + .driver = { > + .name = DRV_NAME, > + .owner = THIS_MODULE, > + .of_match_table = of_match_ptr(isl12057_dt_match), > + }, > + .probe = isl12057_probe, > + .id_table = isl12057_id, > +}; > +module_i2c_driver(isl12057_driver); > + > +MODULE_AUTHOR("Arnaud EBALARD <arno@xxxxxxxxxxxx>"); > +MODULE_DESCRIPTION("Intersil ISL12057 RTC driver"); > +MODULE_LICENSE("GPL"); > -- > 1.8.4.4 > > -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
