diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0137-rtc-ds1307-add-support-for-the-DT-property-wakeup-so.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.4/0137-rtc-ds1307-add-support-for-the-DT-property-wakeup-so.patch | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0137-rtc-ds1307-add-support-for-the-DT-property-wakeup-so.patch b/target/linux/brcm2708/patches-4.4/0137-rtc-ds1307-add-support-for-the-DT-property-wakeup-so.patch new file mode 100644 index 0000000000..8bdbc78c0d --- /dev/null +++ b/target/linux/brcm2708/patches-4.4/0137-rtc-ds1307-add-support-for-the-DT-property-wakeup-so.patch @@ -0,0 +1,94 @@ +From 6f5d0a941a6a084c677a8843207a42f7b6d5a04d Mon Sep 17 00:00:00 2001 +From: Michael Lange <linuxstuff@milaw.biz> +Date: Thu, 21 Jan 2016 18:10:16 +0100 +Subject: [PATCH 137/232] rtc: ds1307: add support for the DT property + 'wakeup-source' + +For RTC chips with no IRQ directly connected to the SoC, the RTC chip +can be forced as a wakeup source by stating that explicitly in +the device's .dts file using the "wakeup-source" boolean property. +This will guarantee the 'wakealarm' sysfs entry is available on the +device, if supported by the RTC. + +With these changes to the driver rtc-ds1307 and the necessary entries +in the .dts file, I get an working ds1337 RTC on the Witty Pi extension +board by UUGear for the Raspberry Pi. + +An example for the entry in the .dts file: + + rtc: ds1337@68 { + compatible = "dallas,ds1337"; + reg = <0x68>; + wakeup-source; + +If the "wakeup-source" property is set, do not request an IRQ. +Set also UIE mode to unsupported, to get a working 'hwclock' binary. + +Signed-off-by: Michael Lange <linuxstuff@milaw.biz> +Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> +--- + drivers/rtc/rtc-ds1307.c | 29 +++++++++++++++++++++++++++-- + 1 file changed, 27 insertions(+), 2 deletions(-) + +--- a/drivers/rtc/rtc-ds1307.c ++++ b/drivers/rtc/rtc-ds1307.c +@@ -860,6 +860,7 @@ static int ds1307_probe(struct i2c_clien + struct chip_desc *chip = &chips[id->driver_data]; + struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); + bool want_irq = false; ++ bool ds1307_can_wakeup_device = false; + unsigned char *buf; + struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev); + irq_handler_t irq_handler = ds1307_irq; +@@ -907,6 +908,20 @@ static int ds1307_probe(struct i2c_clien + ds1307->write_block_data = ds1307_write_block_data; + } + ++#ifdef CONFIG_OF ++/* ++ * For devices with no IRQ directly connected to the SoC, the RTC chip ++ * can be forced as a wakeup source by stating that explicitly in ++ * the device's .dts file using the "wakeup-source" boolean property. ++ * If the "wakeup-source" property is set, don't request an IRQ. ++ * This will guarantee the 'wakealarm' sysfs entry is available on the device, ++ * if supported by the RTC. ++ */ ++ if (of_property_read_bool(client->dev.of_node, "wakeup-source")) { ++ ds1307_can_wakeup_device = true; ++ } ++#endif ++ + switch (ds1307->type) { + case ds_1337: + case ds_1339: +@@ -925,11 +940,13 @@ static int ds1307_probe(struct i2c_clien + ds1307->regs[0] &= ~DS1337_BIT_nEOSC; + + /* +- * Using IRQ? Disable the square wave and both alarms. ++ * Using IRQ or defined as wakeup-source? ++ * Disable the square wave and both alarms. + * For some variants, be sure alarms can trigger when we're + * running on Vbackup (BBSQI/BBSQW) + */ +- if (ds1307->client->irq > 0 && chip->alarm) { ++ if (chip->alarm && (ds1307->client->irq > 0 || ++ ds1307_can_wakeup_device)) { + ds1307->regs[0] |= DS1337_BIT_INTCN + | bbsqi_bitpos[ds1307->type]; + ds1307->regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE); +@@ -1144,6 +1161,14 @@ read_rtc: + return PTR_ERR(ds1307->rtc); + } + ++ if (ds1307_can_wakeup_device) { ++ /* Disable request for an IRQ */ ++ want_irq = false; ++ dev_info(&client->dev, "'wakeup-source' is set, request for an IRQ is disabled!\n"); ++ /* We cannot support UIE mode if we do not have an IRQ line */ ++ ds1307->rtc->uie_unsupported = 1; ++ } ++ + if (want_irq) { + err = devm_request_threaded_irq(&client->dev, + client->irq, NULL, irq_handler, |