diff options
Diffstat (limited to 'drivers/rtc')
| -rw-r--r-- | drivers/rtc/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/rtc/Makefile | 1 | ||||
| -rw-r--r-- | drivers/rtc/rtc-dm355evm.c | 175 | ||||
| -rw-r--r-- | drivers/rtc/rtc-ds1390.c | 1 | ||||
| -rw-r--r-- | drivers/rtc/rtc-pxa.c | 2 | ||||
| -rw-r--r-- | drivers/rtc/rtc-twl4030.c | 49 |
6 files changed, 197 insertions, 37 deletions
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig index cced4d108319..81450fbd8b12 100644 --- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -241,6 +241,12 @@ config RTC_DRV_M41T80_WDT If you say Y here you will get support for the watchdog timer in the ST M41T60 and M41T80 RTC chips series. +config RTC_DRV_DM355EVM + tristate "TI DaVinci DM355 EVM RTC" + depends on MFD_DM355EVM_MSP + help + Supports the RTC firmware in the MSP430 on the DM355 EVM. + config RTC_DRV_TWL92330 boolean "TI TWL92330/Menelaus" depends on MENELAUS diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 6e28021abb9d..0e697aa51caa 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -23,6 +23,7 @@ obj-$(CONFIG_RTC_DRV_AT91SAM9) += rtc-at91sam9.o obj-$(CONFIG_RTC_DRV_AU1XXX) += rtc-au1xxx.o obj-$(CONFIG_RTC_DRV_BFIN) += rtc-bfin.o obj-$(CONFIG_RTC_DRV_CMOS) += rtc-cmos.o +obj-$(CONFIG_RTC_DRV_DM355EVM) += rtc-dm355evm.o obj-$(CONFIG_RTC_DRV_DS1216) += rtc-ds1216.o obj-$(CONFIG_RTC_DRV_DS1286) += rtc-ds1286.o obj-$(CONFIG_RTC_DRV_DS1302) += rtc-ds1302.o diff --git a/drivers/rtc/rtc-dm355evm.c b/drivers/rtc/rtc-dm355evm.c new file mode 100644 index 000000000000..58d4e18530da --- /dev/null +++ b/drivers/rtc/rtc-dm355evm.c @@ -0,0 +1,175 @@ +/* + * rtc-dm355evm.c - access battery-backed counter in MSP430 firmware + * + * Copyright (c) 2008 by David Brownell + * + * 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. + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/rtc.h> +#include <linux/platform_device.h> + +#include <linux/i2c/dm355evm_msp.h> + + +/* + * The MSP430 firmware on the DM355 EVM uses a watch crystal to feed + * a 1 Hz counter. When a backup battery is supplied, that makes a + * reasonable RTC for applications where alarms and non-NTP drift + * compensation aren't important. + * + * The only real glitch is the inability to read or write all four + * counter bytes atomically: the count may increment in the middle + * of an operation, causing trouble when the LSB rolls over. + * + * This driver was tested with firmware revision A4. + */ +union evm_time { + u8 bytes[4]; + u32 value; +}; + +static int dm355evm_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + union evm_time time; + int status; + int tries = 0; + + do { + /* + * Read LSB(0) to MSB(3) bytes. Defend against the counter + * rolling over by re-reading until the value is stable, + * and assuming the four reads take at most a few seconds. + */ + status = dm355evm_msp_read(DM355EVM_MSP_RTC_0); + if (status < 0) + return status; + if (tries && time.bytes[0] == status) + break; + time.bytes[0] = status; + + status = dm355evm_msp_read(DM355EVM_MSP_RTC_1); + if (status < 0) + return status; + if (tries && time.bytes[1] == status) + break; + time.bytes[1] = status; + + status = dm355evm_msp_read(DM355EVM_MSP_RTC_2); + if (status < 0) + return status; + if (tries && time.bytes[2] == status) + break; + time.bytes[2] = status; + + status = dm355evm_msp_read(DM355EVM_MSP_RTC_3); + if (status < 0) + return status; + if (tries && time.bytes[3] == status) + break; + time.bytes[3] = status; + + } while (++tries < 5); + + dev_dbg(dev, "read timestamp %08x\n", time.value); + + rtc_time_to_tm(le32_to_cpu(time.value), tm); + return 0; +} + +static int dm355evm_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + union evm_time time; + unsigned long value; + int status; + + rtc_tm_to_time(tm, &value); + time.value = cpu_to_le32(value); + + dev_dbg(dev, "write timestamp %08x\n", time.value); + + /* + * REVISIT handle non-atomic writes ... maybe just retry until + * byte[1] sticks (no rollover)? + */ + status = dm355evm_msp_write(time.bytes[0], DM355EVM_MSP_RTC_0); + if (status < 0) + return status; + + status = dm355evm_msp_write(time.bytes[1], DM355EVM_MSP_RTC_1); + if (status < 0) + return status; + + status = dm355evm_msp_write(time.bytes[2], DM355EVM_MSP_RTC_2); + if (status < 0) + return status; + + status = dm355evm_msp_write(time.bytes[3], DM355EVM_MSP_RTC_3); + if (status < 0) + return status; + + return 0; +} + +static struct rtc_class_ops dm355evm_rtc_ops = { + .read_time = dm355evm_rtc_read_time, + .set_time = dm355evm_rtc_set_time, +}; + +/*----------------------------------------------------------------------*/ + +static int __devinit dm355evm_rtc_probe(struct platform_device *pdev) +{ + struct rtc_device *rtc; + + rtc = rtc_device_register(pdev->name, + &pdev->dev, &dm355evm_rtc_ops, THIS_MODULE); + if (IS_ERR(rtc)) { + dev_err(&pdev->dev, "can't register RTC device, err %ld\n", + PTR_ERR(rtc)); + return PTR_ERR(rtc); + } + platform_set_drvdata(pdev, rtc); + + return 0; +} + +static int __devexit dm355evm_rtc_remove(struct platform_device *pdev) +{ + struct rtc_device *rtc = platform_get_drvdata(pdev); + + rtc_device_unregister(rtc); + platform_set_drvdata(pdev, NULL); + return 0; +} + +/* + * I2C is used to talk to the MSP430, but this platform device is + * exposed by an MFD driver that manages I2C communications. + */ +static struct platform_driver rtc_dm355evm_driver = { + .probe = dm355evm_rtc_probe, + .remove = __devexit_p(dm355evm_rtc_remove), + .driver = { + .owner = THIS_MODULE, + .name = "rtc-dm355evm", + }, +}; + +static int __init dm355evm_rtc_init(void) +{ + return platform_driver_register(&rtc_dm355evm_driver); +} +module_init(dm355evm_rtc_init); + +static void __exit dm355evm_rtc_exit(void) +{ + platform_driver_unregister(&rtc_dm355evm_driver); +} +module_exit(dm355evm_rtc_exit); + +MODULE_LICENSE("GPL"); diff --git a/drivers/rtc/rtc-ds1390.c b/drivers/rtc/rtc-ds1390.c index e54b5c619bdf..e01b955db077 100644 --- a/drivers/rtc/rtc-ds1390.c +++ b/drivers/rtc/rtc-ds1390.c @@ -122,7 +122,6 @@ static const struct rtc_class_ops ds1390_rtc_ops = { static int __devinit ds1390_probe(struct spi_device *spi) { - struct rtc_device *rtc; unsigned char tmp; struct ds1390 *chip; int res; diff --git a/drivers/rtc/rtc-pxa.c b/drivers/rtc/rtc-pxa.c index cc7eb8767b82..bd56a033bfd0 100644 --- a/drivers/rtc/rtc-pxa.c +++ b/drivers/rtc/rtc-pxa.c @@ -27,6 +27,8 @@ #include <linux/interrupt.h> #include <linux/io.h> +#include <mach/hardware.h> + #define TIMER_FREQ CLOCK_TICK_RATE #define RTC_DEF_DIVIDER (32768 - 1) #define RTC_DEF_TRIM 0 diff --git a/drivers/rtc/rtc-twl4030.c b/drivers/rtc/rtc-twl4030.c index 8ce5f74ee45b..ad35f76c46b7 100644 --- a/drivers/rtc/rtc-twl4030.c +++ b/drivers/rtc/rtc-twl4030.c @@ -120,7 +120,7 @@ static int twl4030_rtc_write_u8(u8 data, u8 reg) static unsigned char rtc_irq_bits; /* - * Enable timer and/or alarm interrupts. + * Enable 1/second update and/or alarm interrupts. */ static int set_rtc_irq_bit(unsigned char bit) { @@ -128,6 +128,7 @@ static int set_rtc_irq_bit(unsigned char bit) int ret; val = rtc_irq_bits | bit; + val &= ~BIT_RTC_INTERRUPTS_REG_EVERY_M; ret = twl4030_rtc_write_u8(val, REG_RTC_INTERRUPTS_REG); if (ret == 0) rtc_irq_bits = val; @@ -136,7 +137,7 @@ static int set_rtc_irq_bit(unsigned char bit) } /* - * Disable timer and/or alarm interrupts. + * Disable update and/or alarm interrupts. */ static int mask_rtc_irq_bit(unsigned char bit) { @@ -151,7 +152,7 @@ static int mask_rtc_irq_bit(unsigned char bit) return ret; } -static inline int twl4030_rtc_alarm_irq_set_state(int enabled) +static int twl4030_rtc_alarm_irq_enable(struct device *dev, unsigned enabled) { int ret; @@ -163,7 +164,7 @@ static inline int twl4030_rtc_alarm_irq_set_state(int enabled) return ret; } -static inline int twl4030_rtc_irq_set_state(int enabled) +static int twl4030_rtc_update_irq_enable(struct device *dev, unsigned enabled) { int ret; @@ -292,7 +293,7 @@ static int twl4030_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) unsigned char alarm_data[ALL_TIME_REGS + 1]; int ret; - ret = twl4030_rtc_alarm_irq_set_state(0); + ret = twl4030_rtc_alarm_irq_enable(dev, 0); if (ret) goto out; @@ -312,35 +313,11 @@ static int twl4030_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) } if (alm->enabled) - ret = twl4030_rtc_alarm_irq_set_state(1); + ret = twl4030_rtc_alarm_irq_enable(dev, 1); out: return ret; } -#ifdef CONFIG_RTC_INTF_DEV - -static int twl4030_rtc_ioctl(struct device *dev, unsigned int cmd, - unsigned long arg) -{ - switch (cmd) { - case RTC_AIE_OFF: - return twl4030_rtc_alarm_irq_set_state(0); - case RTC_AIE_ON: - return twl4030_rtc_alarm_irq_set_state(1); - case RTC_UIE_OFF: - return twl4030_rtc_irq_set_state(0); - case RTC_UIE_ON: - return twl4030_rtc_irq_set_state(1); - - default: - return -ENOIOCTLCMD; - } -} - -#else -#define twl4030_rtc_ioctl NULL -#endif - static irqreturn_t twl4030_rtc_interrupt(int irq, void *rtc) { unsigned long events = 0; @@ -400,11 +377,12 @@ out: } static struct rtc_class_ops twl4030_rtc_ops = { - .ioctl = twl4030_rtc_ioctl, .read_time = twl4030_rtc_read_time, .set_time = twl4030_rtc_set_time, .read_alarm = twl4030_rtc_read_alarm, .set_alarm = twl4030_rtc_set_alarm, + .alarm_irq_enable = twl4030_rtc_alarm_irq_enable, + .update_irq_enable = twl4030_rtc_update_irq_enable, }; /*----------------------------------------------------------------------*/ @@ -422,7 +400,7 @@ static int __devinit twl4030_rtc_probe(struct platform_device *pdev) rtc = rtc_device_register(pdev->name, &pdev->dev, &twl4030_rtc_ops, THIS_MODULE); if (IS_ERR(rtc)) { - ret = -EINVAL; + ret = PTR_ERR(rtc); dev_err(&pdev->dev, "can't register RTC device, err %ld\n", PTR_ERR(rtc)); goto out0; @@ -432,7 +410,6 @@ static int __devinit twl4030_rtc_probe(struct platform_device *pdev) platform_set_drvdata(pdev, rtc); ret = twl4030_rtc_read_u8(&rd_reg, REG_RTC_STATUS_REG); - if (ret < 0) goto out1; @@ -475,7 +452,6 @@ static int __devinit twl4030_rtc_probe(struct platform_device *pdev) return ret; - out2: free_irq(irq, rtc); out1: @@ -506,8 +482,9 @@ static int __devexit twl4030_rtc_remove(struct platform_device *pdev) static void twl4030_rtc_shutdown(struct platform_device *pdev) { - mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M | - BIT_RTC_INTERRUPTS_REG_IT_ALARM_M); + /* mask timer interrupts, but leave alarm interrupts on to enable + power-on when alarm is triggered */ + mask_rtc_irq_bit(BIT_RTC_INTERRUPTS_REG_IT_TIMER_M); } #ifdef CONFIG_PM |