| Message ID | 1458134390-23847-3-git-send-email-nicolas.ferre@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 16/03/2016 at 14:19:50 +0100, Nicolas Ferre wrote : > Sama5d2 SoC has a completely new shutdown controller with new features and > register layout. It thus makes sense to add a new driver for this new > peripheral. > > This driver is Device Tree only and handles events from the wake-up pin and > the RTC. > As the register layout may change in the future, so some values are encoded > in a configuration structure. > > Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> > --- > > Changes in v5: > - Instead of the "alternate shdwc" we choose a more specific > "sama5d2-compatible shdwc" wording. Change file name, in Kconfig, and the > MAINTAINERS file: > at91-shdwc.c -> at91-sama5d2_shdwc.c > "ATMEL AT91 Alternative Shutdown Controller" -> "ATMEL AT91 SAMA5D2-Compatible > Shutdown Controller" > - fix one indentation mismatch > > Changes in v4: > - fix warning found by 0-day robot: large integer implicitly truncated to > unsigned type [-Woverflow] > - move to the property debounce-delay-us > - move to atmel,wakeup-active-high boolean > - add entry in MAINTAINERS file > > Changes in v3: > - add the slow clock handle as the IP uses it > - remove useless protection at the beginning of pm_power_off handler > - allow to compile it as a module > - add COMPILE_TEST directive in Kconfig > - update description in file header > > Changes in v2: > - add MODULE_DEVICE_TABLE as advised by Sebastian Reichel > - review indentation and braces to correct errors pointed out by checkpatch > > MAINTAINERS | 5 + > drivers/power/reset/Kconfig | 8 + > drivers/power/reset/Makefile | 1 + > drivers/power/reset/at91-sama5d2_shdwc.c | 282 +++++++++++++++++++++++++++++++ > 4 files changed, 296 insertions(+) > create mode 100644 drivers/power/reset/at91-sama5d2_shdwc.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 5744af3d79ab..a05b14d8d4d2 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -1999,6 +1999,11 @@ M: Nicolas Ferre <nicolas.ferre@atmel.com> > S: Supported > F: drivers/tty/serial/atmel_serial.c > > +ATMEL AT91 SAMA5D2-Compatible Shutdown Controller > +M: Nicolas Ferre <nicolas.ferre@atmel.com> > +S: Supported > +F: drivers/power/reset/at91-sama5d2_shdwc.c > + > ATMEL SAMA5D2 ADC DRIVER > M: Ludovic Desroches <ludovic.desroches@atmel.com> > L: linux-iio@vger.kernel.org > diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig > index 0a6408a39c66..9bb2622c23bf 100644 > --- a/drivers/power/reset/Kconfig > +++ b/drivers/power/reset/Kconfig > @@ -30,6 +30,14 @@ config POWER_RESET_AT91_RESET > This driver supports restart for Atmel AT91SAM9 and SAMA5 > SoCs > > +config POWER_RESET_AT91_SAMA5D2_SHDWC > + tristate "Atmel AT91 SAMA5D2-Compatible shutdown controller driver" > + depends on ARCH_AT91 || COMPILE_TEST > + default SOC_SAMA5 > + help > + This driver supports the alternate shutdown controller for some Atmel > + SAMA5 SoCs. It is present for example on SAMA5D2 SoC. > + > config POWER_RESET_AXXIA > bool "LSI Axxia reset driver" > depends on ARCH_AXXIA > diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile > index 096fa67047f6..ab7aa8614d1f 100644 > --- a/drivers/power/reset/Makefile > +++ b/drivers/power/reset/Makefile > @@ -1,6 +1,7 @@ > obj-$(CONFIG_POWER_RESET_AS3722) += as3722-poweroff.o > obj-$(CONFIG_POWER_RESET_AT91_POWEROFF) += at91-poweroff.o > obj-$(CONFIG_POWER_RESET_AT91_RESET) += at91-reset.o > +obj-$(CONFIG_POWER_RESET_AT91_SAMA5D2_SHDWC) += at91-sama5d2_shdwc.o > obj-$(CONFIG_POWER_RESET_AXXIA) += axxia-reset.o > obj-$(CONFIG_POWER_RESET_BRCMSTB) += brcmstb-reboot.o > obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o > diff --git a/drivers/power/reset/at91-sama5d2_shdwc.c b/drivers/power/reset/at91-sama5d2_shdwc.c > new file mode 100644 > index 000000000000..8a5ac9706c9c > --- /dev/null > +++ b/drivers/power/reset/at91-sama5d2_shdwc.c > @@ -0,0 +1,282 @@ > +/* > + * Atmel SAMA5D2-Compatible Shutdown Controller (SHDWC) driver. > + * Found on some SoCs as the sama5d2 (obviously). > + * > + * Copyright (C) 2015 Atmel Corporation, > + * Nicolas Ferre <nicolas.ferre@atmel.com> > + * > + * Evolved from driver at91-poweroff.c. > + * > + * This file is licensed under the terms of the GNU General Public > + * License version 2. This program is licensed "as is" without any > + * warranty of any kind, whether express or implied. > + * > + * TODO: > + * - addition to status of other wake-up inputs [1 - 15] > + * - Analog Comparator wake-up alarm > + * - Serial RX wake-up alarm > + * - low power debouncer > + */ > + > +#include <linux/clk.h> > +#include <linux/io.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/printk.h> > + > +#define SLOW_CLOCK_FREQ 32768 > + > +#define AT91_SHDW_CR 0x00 /* Shut Down Control Register */ > +#define AT91_SHDW_SHDW BIT(0) /* Shut Down command */ > +#define AT91_SHDW_KEY (0xa5UL << 24) /* KEY Password */ > + > +#define AT91_SHDW_MR 0x04 /* Shut Down Mode Register */ > +#define AT91_SHDW_WKUPDBC_SHIFT 24 > +#define AT91_SHDW_WKUPDBC_MASK GENMASK(31, 16) > +#define AT91_SHDW_WKUPDBC(x) (((x) << AT91_SHDW_WKUPDBC_SHIFT) \ > + & AT91_SHDW_WKUPDBC_MASK) > + > +#define AT91_SHDW_SR 0x08 /* Shut Down Status Register */ > +#define AT91_SHDW_WKUPIS_SHIFT 16 > +#define AT91_SHDW_WKUPIS_MASK GENMASK(31, 16) > +#define AT91_SHDW_WKUPIS(x) ((1 << (x)) << AT91_SHDW_WKUPIS_SHIFT \ > + & AT91_SHDW_WKUPIS_MASK) > + > +#define AT91_SHDW_WUIR 0x0c /* Shutdown Wake-up Inputs Register */ > +#define AT91_SHDW_WKUPEN_MASK GENMASK(15, 0) > +#define AT91_SHDW_WKUPEN(x) ((1 << (x)) & AT91_SHDW_WKUPEN_MASK) > +#define AT91_SHDW_WKUPT_SHIFT 16 > +#define AT91_SHDW_WKUPT_MASK GENMASK(31, 16) > +#define AT91_SHDW_WKUPT(x) ((1 << (x)) << AT91_SHDW_WKUPT_SHIFT \ > + & AT91_SHDW_WKUPT_MASK) > + > +#define SHDW_WK_PIN(reg, cfg) ((reg) & AT91_SHDW_WKUPIS((cfg)->wkup_pin_input)) > +#define SHDW_RTCWK(reg, cfg) (((reg) >> ((cfg)->sr_rtcwk_shift)) & 0x1) > +#define SHDW_RTCWKEN(cfg) (1 << ((cfg)->mr_rtcwk_shift)) > + > +#define DBC_PERIOD_US(x) DIV_ROUND_UP_ULL((1000000 * (x)), \ > + SLOW_CLOCK_FREQ) > + > +struct shdwc_config { > + u8 wkup_pin_input; > + u8 mr_rtcwk_shift; > + u8 sr_rtcwk_shift; > +}; > + > +struct shdwc { > + struct shdwc_config *cfg; > + void __iomem *at91_shdwc_base; > +}; > + > +/* > + * Hold configuration here, cannot be more than one instance of the driver > + * since pm_power_off itself is global. > + */ > +static struct shdwc *at91_shdwc; > +static struct clk *sclk; > + > +static const unsigned long long sdwc_dbc_period[] = { > + 0, 3, 32, 512, 4096, 32768, > +}; > + > +static void __init at91_wakeup_status(struct platform_device *pdev) > +{ > + struct shdwc *shdw = platform_get_drvdata(pdev); > + u32 reg; > + char *reason = "unknown"; > + > + reg = readl(shdw->at91_shdwc_base + AT91_SHDW_SR); > + > + dev_dbg(&pdev->dev, "%s: status = %#x\n", __func__, reg); > + > + /* Simple power-on, just bail out */ > + if (!reg) > + return; > + > + if (SHDW_WK_PIN(reg, shdw->cfg)) > + reason = "WKUP pin"; > + else if (SHDW_RTCWK(reg, shdw->cfg)) > + reason = "RTC"; > + > + pr_info("AT91: Wake-Up source: %s\n", reason); > +} > + > +static void at91_poweroff(void) > +{ > + writel(AT91_SHDW_KEY | AT91_SHDW_SHDW, > + at91_shdwc->at91_shdwc_base + AT91_SHDW_CR); > +} > + > +static u32 at91_shdwc_debouncer_value(struct platform_device *pdev, > + u32 in_period_us) > +{ > + int i; > + int max_idx = ARRAY_SIZE(sdwc_dbc_period) - 1; > + unsigned long long period_us; > + unsigned long long max_period_us = DBC_PERIOD_US(sdwc_dbc_period[max_idx]); > + > + if (in_period_us > max_period_us) { > + dev_warn(&pdev->dev, > + "debouncer period %u too big, reduced to %llu us\n", > + in_period_us, max_period_us); > + return max_idx; > + } > + > + for (i = max_idx - 1; i > 0; i--) { > + period_us = DBC_PERIOD_US(sdwc_dbc_period[i]); > + dev_dbg(&pdev->dev, "%s: ref[%d] = %llu\n", > + __func__, i, period_us); > + if (in_period_us > period_us) > + break; > + } > + > + return i + 1; > +} > + > +static u32 at91_shdwc_get_wakeup_input(struct platform_device *pdev, > + struct device_node *np) > +{ > + struct device_node *cnp; > + u32 wk_input_mask; > + u32 wuir = 0; > + u32 wk_input; > + > + for_each_child_of_node(np, cnp) { > + if (of_property_read_u32(cnp, "reg", &wk_input)) { > + dev_warn(&pdev->dev, "reg property is missing for %s\n", > + cnp->full_name); > + continue; > + } > + > + wk_input_mask = 1 << wk_input; > + if (!(wk_input_mask & AT91_SHDW_WKUPEN_MASK)) { > + dev_warn(&pdev->dev, > + "wake-up input %d out of bounds ignore\n", > + wk_input); > + continue; > + } > + wuir |= wk_input_mask; > + > + if (of_property_read_bool(cnp, "atmel,wakeup-active-high")) > + wuir |= AT91_SHDW_WKUPT(wk_input); > + > + dev_dbg(&pdev->dev, "%s: (child %d) wuir = %#x\n", > + __func__, wk_input, wuir); > + } > + > + return wuir; > +} > + > +static void at91_shdwc_dt_configure(struct platform_device *pdev) > +{ > + struct shdwc *shdw = platform_get_drvdata(pdev); > + struct device_node *np = pdev->dev.of_node; > + u32 mode = 0, tmp, input; > + > + if (!np) { > + dev_err(&pdev->dev, "device node not found\n"); > + return; > + } > + > + if (!of_property_read_u32(np, "debounce-delay-us", &tmp)) > + mode |= AT91_SHDW_WKUPDBC(at91_shdwc_debouncer_value(pdev, tmp)); > + > + if (of_property_read_bool(np, "atmel,wakeup-rtc-timer")) > + mode |= SHDW_RTCWKEN(shdw->cfg); > + > + dev_dbg(&pdev->dev, "%s: mode = %#x\n", __func__, mode); > + writel(mode, shdw->at91_shdwc_base + AT91_SHDW_MR); > + > + input = at91_shdwc_get_wakeup_input(pdev, np); > + writel(input, shdw->at91_shdwc_base + AT91_SHDW_WUIR); > +} > + > +static const struct shdwc_config sama5d2_shdwc_config = { > + .wkup_pin_input = 0, > + .mr_rtcwk_shift = 17, > + .sr_rtcwk_shift = 5, > +}; > + > +static const struct of_device_id at91_shdwc_of_match[] = { > + { > + .compatible = "atmel,sama5d2-shdwc", > + .data = &sama5d2_shdwc_config, > + }, { > + /*sentinel*/ > + } > +}; > +MODULE_DEVICE_TABLE(of, at91_shdwc_of_match); > + > +static int __init at91_shdwc_probe(struct platform_device *pdev) > +{ > + struct resource *res; > + const struct of_device_id *match; > + int ret; > + > + if (!pdev->dev.of_node) > + return -ENODEV; > + > + at91_shdwc = devm_kzalloc(&pdev->dev, sizeof(*at91_shdwc), GFP_KERNEL); > + if (!at91_shdwc) > + return -ENOMEM; > + > + platform_set_drvdata(pdev, at91_shdwc); > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + at91_shdwc->at91_shdwc_base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(at91_shdwc->at91_shdwc_base)) { > + dev_err(&pdev->dev, "Could not map reset controller address\n"); > + return PTR_ERR(at91_shdwc->at91_shdwc_base); > + } > + > + match = of_match_node(at91_shdwc_of_match, pdev->dev.of_node); > + at91_shdwc->cfg = (struct shdwc_config *)(match->data); > + > + sclk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(sclk)) > + return PTR_ERR(sclk); > + > + ret = clk_prepare_enable(sclk); > + if (ret) { > + dev_err(&pdev->dev, "Could not enable slow clock\n"); > + return ret; > + } > + > + at91_wakeup_status(pdev); > + > + at91_shdwc_dt_configure(pdev); > + > + pm_power_off = at91_poweroff; > + > + return 0; > +} > + > +static int __exit at91_shdwc_remove(struct platform_device *pdev) > +{ > + struct shdwc *shdw = platform_get_drvdata(pdev); > + > + if (pm_power_off == at91_poweroff) > + pm_power_off = NULL; > + > + /* Reset values to disable wake-up features */ > + writel(0, shdw->at91_shdwc_base + AT91_SHDW_MR); > + writel(0, shdw->at91_shdwc_base + AT91_SHDW_WUIR); > + > + clk_disable_unprepare(sclk); > + > + return 0; > +} > + > +static struct platform_driver at91_shdwc_driver = { > + .remove = __exit_p(at91_shdwc_remove), > + .driver = { > + .name = "at91-shdwc", > + .of_match_table = at91_shdwc_of_match, > + }, > +}; > +module_platform_driver_probe(at91_shdwc_driver, at91_shdwc_probe); > + > +MODULE_AUTHOR("Nicolas Ferre <nicolas.ferre@atmel.com>"); > +MODULE_DESCRIPTION("Atmel shutdown controller driver"); > +MODULE_LICENSE("GPL v2"); > -- > 2.1.3 >
diff --git a/MAINTAINERS b/MAINTAINERS index 5744af3d79ab..a05b14d8d4d2 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1999,6 +1999,11 @@ M: Nicolas Ferre <nicolas.ferre@atmel.com> S: Supported F: drivers/tty/serial/atmel_serial.c +ATMEL AT91 SAMA5D2-Compatible Shutdown Controller +M: Nicolas Ferre <nicolas.ferre@atmel.com> +S: Supported +F: drivers/power/reset/at91-sama5d2_shdwc.c + ATMEL SAMA5D2 ADC DRIVER M: Ludovic Desroches <ludovic.desroches@atmel.com> L: linux-iio@vger.kernel.org diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index 0a6408a39c66..9bb2622c23bf 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -30,6 +30,14 @@ config POWER_RESET_AT91_RESET This driver supports restart for Atmel AT91SAM9 and SAMA5 SoCs +config POWER_RESET_AT91_SAMA5D2_SHDWC + tristate "Atmel AT91 SAMA5D2-Compatible shutdown controller driver" + depends on ARCH_AT91 || COMPILE_TEST + default SOC_SAMA5 + help + This driver supports the alternate shutdown controller for some Atmel + SAMA5 SoCs. It is present for example on SAMA5D2 SoC. + config POWER_RESET_AXXIA bool "LSI Axxia reset driver" depends on ARCH_AXXIA diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index 096fa67047f6..ab7aa8614d1f 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -1,6 +1,7 @@ obj-$(CONFIG_POWER_RESET_AS3722) += as3722-poweroff.o obj-$(CONFIG_POWER_RESET_AT91_POWEROFF) += at91-poweroff.o obj-$(CONFIG_POWER_RESET_AT91_RESET) += at91-reset.o +obj-$(CONFIG_POWER_RESET_AT91_SAMA5D2_SHDWC) += at91-sama5d2_shdwc.o obj-$(CONFIG_POWER_RESET_AXXIA) += axxia-reset.o obj-$(CONFIG_POWER_RESET_BRCMSTB) += brcmstb-reboot.o obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o diff --git a/drivers/power/reset/at91-sama5d2_shdwc.c b/drivers/power/reset/at91-sama5d2_shdwc.c new file mode 100644 index 000000000000..8a5ac9706c9c --- /dev/null +++ b/drivers/power/reset/at91-sama5d2_shdwc.c @@ -0,0 +1,282 @@ +/* + * Atmel SAMA5D2-Compatible Shutdown Controller (SHDWC) driver. + * Found on some SoCs as the sama5d2 (obviously). + * + * Copyright (C) 2015 Atmel Corporation, + * Nicolas Ferre <nicolas.ferre@atmel.com> + * + * Evolved from driver at91-poweroff.c. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + * + * TODO: + * - addition to status of other wake-up inputs [1 - 15] + * - Analog Comparator wake-up alarm + * - Serial RX wake-up alarm + * - low power debouncer + */ + +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/printk.h> + +#define SLOW_CLOCK_FREQ 32768 + +#define AT91_SHDW_CR 0x00 /* Shut Down Control Register */ +#define AT91_SHDW_SHDW BIT(0) /* Shut Down command */ +#define AT91_SHDW_KEY (0xa5UL << 24) /* KEY Password */ + +#define AT91_SHDW_MR 0x04 /* Shut Down Mode Register */ +#define AT91_SHDW_WKUPDBC_SHIFT 24 +#define AT91_SHDW_WKUPDBC_MASK GENMASK(31, 16) +#define AT91_SHDW_WKUPDBC(x) (((x) << AT91_SHDW_WKUPDBC_SHIFT) \ + & AT91_SHDW_WKUPDBC_MASK) + +#define AT91_SHDW_SR 0x08 /* Shut Down Status Register */ +#define AT91_SHDW_WKUPIS_SHIFT 16 +#define AT91_SHDW_WKUPIS_MASK GENMASK(31, 16) +#define AT91_SHDW_WKUPIS(x) ((1 << (x)) << AT91_SHDW_WKUPIS_SHIFT \ + & AT91_SHDW_WKUPIS_MASK) + +#define AT91_SHDW_WUIR 0x0c /* Shutdown Wake-up Inputs Register */ +#define AT91_SHDW_WKUPEN_MASK GENMASK(15, 0) +#define AT91_SHDW_WKUPEN(x) ((1 << (x)) & AT91_SHDW_WKUPEN_MASK) +#define AT91_SHDW_WKUPT_SHIFT 16 +#define AT91_SHDW_WKUPT_MASK GENMASK(31, 16) +#define AT91_SHDW_WKUPT(x) ((1 << (x)) << AT91_SHDW_WKUPT_SHIFT \ + & AT91_SHDW_WKUPT_MASK) + +#define SHDW_WK_PIN(reg, cfg) ((reg) & AT91_SHDW_WKUPIS((cfg)->wkup_pin_input)) +#define SHDW_RTCWK(reg, cfg) (((reg) >> ((cfg)->sr_rtcwk_shift)) & 0x1) +#define SHDW_RTCWKEN(cfg) (1 << ((cfg)->mr_rtcwk_shift)) + +#define DBC_PERIOD_US(x) DIV_ROUND_UP_ULL((1000000 * (x)), \ + SLOW_CLOCK_FREQ) + +struct shdwc_config { + u8 wkup_pin_input; + u8 mr_rtcwk_shift; + u8 sr_rtcwk_shift; +}; + +struct shdwc { + struct shdwc_config *cfg; + void __iomem *at91_shdwc_base; +}; + +/* + * Hold configuration here, cannot be more than one instance of the driver + * since pm_power_off itself is global. + */ +static struct shdwc *at91_shdwc; +static struct clk *sclk; + +static const unsigned long long sdwc_dbc_period[] = { + 0, 3, 32, 512, 4096, 32768, +}; + +static void __init at91_wakeup_status(struct platform_device *pdev) +{ + struct shdwc *shdw = platform_get_drvdata(pdev); + u32 reg; + char *reason = "unknown"; + + reg = readl(shdw->at91_shdwc_base + AT91_SHDW_SR); + + dev_dbg(&pdev->dev, "%s: status = %#x\n", __func__, reg); + + /* Simple power-on, just bail out */ + if (!reg) + return; + + if (SHDW_WK_PIN(reg, shdw->cfg)) + reason = "WKUP pin"; + else if (SHDW_RTCWK(reg, shdw->cfg)) + reason = "RTC"; + + pr_info("AT91: Wake-Up source: %s\n", reason); +} + +static void at91_poweroff(void) +{ + writel(AT91_SHDW_KEY | AT91_SHDW_SHDW, + at91_shdwc->at91_shdwc_base + AT91_SHDW_CR); +} + +static u32 at91_shdwc_debouncer_value(struct platform_device *pdev, + u32 in_period_us) +{ + int i; + int max_idx = ARRAY_SIZE(sdwc_dbc_period) - 1; + unsigned long long period_us; + unsigned long long max_period_us = DBC_PERIOD_US(sdwc_dbc_period[max_idx]); + + if (in_period_us > max_period_us) { + dev_warn(&pdev->dev, + "debouncer period %u too big, reduced to %llu us\n", + in_period_us, max_period_us); + return max_idx; + } + + for (i = max_idx - 1; i > 0; i--) { + period_us = DBC_PERIOD_US(sdwc_dbc_period[i]); + dev_dbg(&pdev->dev, "%s: ref[%d] = %llu\n", + __func__, i, period_us); + if (in_period_us > period_us) + break; + } + + return i + 1; +} + +static u32 at91_shdwc_get_wakeup_input(struct platform_device *pdev, + struct device_node *np) +{ + struct device_node *cnp; + u32 wk_input_mask; + u32 wuir = 0; + u32 wk_input; + + for_each_child_of_node(np, cnp) { + if (of_property_read_u32(cnp, "reg", &wk_input)) { + dev_warn(&pdev->dev, "reg property is missing for %s\n", + cnp->full_name); + continue; + } + + wk_input_mask = 1 << wk_input; + if (!(wk_input_mask & AT91_SHDW_WKUPEN_MASK)) { + dev_warn(&pdev->dev, + "wake-up input %d out of bounds ignore\n", + wk_input); + continue; + } + wuir |= wk_input_mask; + + if (of_property_read_bool(cnp, "atmel,wakeup-active-high")) + wuir |= AT91_SHDW_WKUPT(wk_input); + + dev_dbg(&pdev->dev, "%s: (child %d) wuir = %#x\n", + __func__, wk_input, wuir); + } + + return wuir; +} + +static void at91_shdwc_dt_configure(struct platform_device *pdev) +{ + struct shdwc *shdw = platform_get_drvdata(pdev); + struct device_node *np = pdev->dev.of_node; + u32 mode = 0, tmp, input; + + if (!np) { + dev_err(&pdev->dev, "device node not found\n"); + return; + } + + if (!of_property_read_u32(np, "debounce-delay-us", &tmp)) + mode |= AT91_SHDW_WKUPDBC(at91_shdwc_debouncer_value(pdev, tmp)); + + if (of_property_read_bool(np, "atmel,wakeup-rtc-timer")) + mode |= SHDW_RTCWKEN(shdw->cfg); + + dev_dbg(&pdev->dev, "%s: mode = %#x\n", __func__, mode); + writel(mode, shdw->at91_shdwc_base + AT91_SHDW_MR); + + input = at91_shdwc_get_wakeup_input(pdev, np); + writel(input, shdw->at91_shdwc_base + AT91_SHDW_WUIR); +} + +static const struct shdwc_config sama5d2_shdwc_config = { + .wkup_pin_input = 0, + .mr_rtcwk_shift = 17, + .sr_rtcwk_shift = 5, +}; + +static const struct of_device_id at91_shdwc_of_match[] = { + { + .compatible = "atmel,sama5d2-shdwc", + .data = &sama5d2_shdwc_config, + }, { + /*sentinel*/ + } +}; +MODULE_DEVICE_TABLE(of, at91_shdwc_of_match); + +static int __init at91_shdwc_probe(struct platform_device *pdev) +{ + struct resource *res; + const struct of_device_id *match; + int ret; + + if (!pdev->dev.of_node) + return -ENODEV; + + at91_shdwc = devm_kzalloc(&pdev->dev, sizeof(*at91_shdwc), GFP_KERNEL); + if (!at91_shdwc) + return -ENOMEM; + + platform_set_drvdata(pdev, at91_shdwc); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + at91_shdwc->at91_shdwc_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(at91_shdwc->at91_shdwc_base)) { + dev_err(&pdev->dev, "Could not map reset controller address\n"); + return PTR_ERR(at91_shdwc->at91_shdwc_base); + } + + match = of_match_node(at91_shdwc_of_match, pdev->dev.of_node); + at91_shdwc->cfg = (struct shdwc_config *)(match->data); + + sclk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(sclk)) + return PTR_ERR(sclk); + + ret = clk_prepare_enable(sclk); + if (ret) { + dev_err(&pdev->dev, "Could not enable slow clock\n"); + return ret; + } + + at91_wakeup_status(pdev); + + at91_shdwc_dt_configure(pdev); + + pm_power_off = at91_poweroff; + + return 0; +} + +static int __exit at91_shdwc_remove(struct platform_device *pdev) +{ + struct shdwc *shdw = platform_get_drvdata(pdev); + + if (pm_power_off == at91_poweroff) + pm_power_off = NULL; + + /* Reset values to disable wake-up features */ + writel(0, shdw->at91_shdwc_base + AT91_SHDW_MR); + writel(0, shdw->at91_shdwc_base + AT91_SHDW_WUIR); + + clk_disable_unprepare(sclk); + + return 0; +} + +static struct platform_driver at91_shdwc_driver = { + .remove = __exit_p(at91_shdwc_remove), + .driver = { + .name = "at91-shdwc", + .of_match_table = at91_shdwc_of_match, + }, +}; +module_platform_driver_probe(at91_shdwc_driver, at91_shdwc_probe); + +MODULE_AUTHOR("Nicolas Ferre <nicolas.ferre@atmel.com>"); +MODULE_DESCRIPTION("Atmel shutdown controller driver"); +MODULE_LICENSE("GPL v2");
Sama5d2 SoC has a completely new shutdown controller with new features and register layout. It thus makes sense to add a new driver for this new peripheral. This driver is Device Tree only and handles events from the wake-up pin and the RTC. As the register layout may change in the future, so some values are encoded in a configuration structure. Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> --- Changes in v5: - Instead of the "alternate shdwc" we choose a more specific "sama5d2-compatible shdwc" wording. Change file name, in Kconfig, and the MAINTAINERS file: at91-shdwc.c -> at91-sama5d2_shdwc.c "ATMEL AT91 Alternative Shutdown Controller" -> "ATMEL AT91 SAMA5D2-Compatible Shutdown Controller" - fix one indentation mismatch Changes in v4: - fix warning found by 0-day robot: large integer implicitly truncated to unsigned type [-Woverflow] - move to the property debounce-delay-us - move to atmel,wakeup-active-high boolean - add entry in MAINTAINERS file Changes in v3: - add the slow clock handle as the IP uses it - remove useless protection at the beginning of pm_power_off handler - allow to compile it as a module - add COMPILE_TEST directive in Kconfig - update description in file header Changes in v2: - add MODULE_DEVICE_TABLE as advised by Sebastian Reichel - review indentation and braces to correct errors pointed out by checkpatch MAINTAINERS | 5 + drivers/power/reset/Kconfig | 8 + drivers/power/reset/Makefile | 1 + drivers/power/reset/at91-sama5d2_shdwc.c | 282 +++++++++++++++++++++++++++++++ 4 files changed, 296 insertions(+) create mode 100644 drivers/power/reset/at91-sama5d2_shdwc.c