[PATCH 1/3] power: reset: at91-reset/trivial: driver applies to SAMA5 family as well

[PATCH 1/3] power: reset: at91-reset/trivial: driver applies to SAMA5 family as well

[Nicolas Ferre]

This diver doesn't applies only on SAM9 SoC families but on SAMA5 families
as well.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 drivers/power/reset/at91-reset.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c
index c378d4ec826f..264b9b81b9f7 100644
--- a/drivers/power/reset/at91-reset.c
+++ b/drivers/power/reset/at91-reset.c
@@ -1,5 +1,5 @@
 /*
- * Atmel AT91 SAM9 SoCs reset code
+ * Atmel AT91 SAM9 & SAMA5 SoCs reset code
  *
  * Copyright (C) 2007 Atmel Corporation.
  * Copyright (C) BitBox Ltd 2010
-- 
2.1.3

[PATCH 2/3] ARM: at91/dt: shdwc binding: add new shutdown controller documentation

[Nicolas Ferre]

The new shutdown controller compatible with sama5d2 has a new binding
documentation and properties.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 .../devicetree/bindings/arm/atmel-at91.txt         | 52 ++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/atmel-at91.txt b/Documentation/devicetree/bindings/arm/atmel-at91.txt
index 7fd64ec9ee1d..ec4b183005e4 100644
--- a/Documentation/devicetree/bindings/arm/atmel-at91.txt
+++ b/Documentation/devicetree/bindings/arm/atmel-at91.txt
@@ -147,6 +147,58 @@ Example:
 		clocks = <&clk32k>;
 	};
 
+SHDWC Shutdown Controller (Alternative)
+
+1) shdwc node
+
+required properties:
+- compatible: should be "atmel,sama5d2-shdwc".
+- reg: should contain registers location and length
+- #address-cells: should be one. The cell is the wake-up input index.
+- #size-cells: should be zero.
+
+optional properties:
+
+- atmel,wakeup-debouncer: minimum wake-up inputs debouncer period in
+  micro-seconds. It's usually a board-related property.
+- atmel,wakeup-rtc-timer: boolean to enable Real-Time Clock wake-up.
+
+The node contains child nodes for each wake-up input that the platform uses.
+
+2) input nodes
+
+Wake-up input nodes are usually described in the "board" part of the Device
+Tree. Note also that input 0 is linked to the wake-up pin and is frequently
+used.
+
+Required properties:
+- reg: should contain the wake-up input index [0 - 15].
+
+Optional properties:
+- atmel,wakeup-type: string, operation mode of the input described by the child
+  node. Supported values are: "high" or "low".
+
+Example:
+
+On the SoC side:
+	shdwc at f8048010 {
+		compatible = "atmel,sama5d2-shdwc";
+		reg = <0xf8048010 0x10>;
+		#address-cells = <1>;
+		#size-cells = <0>;
+		atmel,wakeup-rtc-timer;
+	};
+
+On the board side:
+	shdwc at f8048010 {
+		atmel,shdwc-debouncer = <976>;
+
+		input at 0 {
+			reg = <0>;
+			atmel,wakeup-type = "low";
+		};
+	};
+
 Special Function Registers (SFR)
 
 Special Function Registers (SFR) manage specific aspects of the integrated
-- 
2.1.3

[PATCH 3/3] power: reset: at91-shdwc: add new shutdown controller driver

[Nicolas Ferre]

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>
---
 drivers/power/reset/Kconfig      |   8 ++
 drivers/power/reset/Makefile     |   1 +
 drivers/power/reset/at91-shdwc.c | 263 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 272 insertions(+)
 create mode 100644 drivers/power/reset/at91-shdwc.c

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 5a0189bf19bb..7f52bc938795 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_SHDWC
+	bool "Atmel AT91 shutdown controller driver"
+	depends on ARCH_AT91
+	default SOC_SAMA5
+	help
+	  This driver supports poweroff 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..6b9020ed3fb7 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_SHDWC) += at91-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-shdwc.c b/drivers/power/reset/at91-shdwc.c
new file mode 100644
index 000000000000..bc5cbf2bc95b
--- /dev/null
+++ b/drivers/power/reset/at91-shdwc.c
@@ -0,0 +1,263 @@
+/*
+ * Atmel Shutdown Controller (SHDWC) driver
+ *
+ * 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/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		(0xa5 << 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 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)
+{
+	BUG_ON(!at91_shdwc);
+
+	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;
+	const char *pm;
+	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_string(cnp, "atmel,wakeup-type", &pm)) {
+			if (!strcasecmp(pm, "high"))
+				/*
+				 * only add a type if "high" is specified. Low
+				 * is the default.
+				 */
+				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, "atmel,shdwc-debouncer", &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 struct of_device_id at91_shdwc_of_match[] = {
+	{
+		.compatible = "atmel,sama5d2-shdwc",
+                .data = &sama5d2_shdwc_config,
+	}, {
+		/*sentinel*/
+	}
+};
+
+static int at91_shdwc_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	const struct of_device_id *match;
+
+	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);
+	if (match != NULL)
+		at91_shdwc->cfg = (struct shdwc_config *)(match->data);
+	else
+		return -ENODATA;
+
+	at91_wakeup_status(pdev);
+
+	at91_shdwc_dt_configure(pdev);
+
+	pm_power_off = at91_poweroff;
+
+	return 0;
+}
+
+static struct platform_driver at91_shdwc_driver = {
+	.probe = at91_shdwc_probe,
+	.driver = {
+		.name = "at91-shdwc",
+		.of_match_table = at91_shdwc_of_match,
+	},
+};
+module_platform_driver(at91_shdwc_driver);
+
+MODULE_AUTHOR("Nicolas Ferre <nicolas.ferre@atmel.com>");
+MODULE_DESCRIPTION("Atmel shutdown controller driver");
+MODULE_LICENSE("GPL v2");
-- 
2.1.3

[PATCH 1/3] power: reset: at91-reset/trivial: driver applies to SAMA5 family as well

[Sebastian Reichel]

Hi,

On Thu, Sep 10, 2015 at 12:35:13PM +0200, Nicolas Ferre wrote:
> This diver doesn't applies only on SAM9 SoC families but on SAMA5 families
> as well.

Thanks, queued.

-- Sebastian
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[PATCH 3/3] power: reset: at91-shdwc: add new shutdown controller driver

[Sebastian Reichel]

Hi,

On Thu, Sep 10, 2015 at 12:39:18PM +0200, 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.
>
> [...]
>
> +static struct of_device_id at91_shdwc_of_match[] = {
> +	{
> +		.compatible = "atmel,sama5d2-shdwc",
> +                .data = &sama5d2_shdwc_config,
> +	}, {
> +		/*sentinel*/
> +	}
> +};

please add:

MODULE_DEVICE_TABLE(of, at91_shdwc_of_match);

-- Sebastian
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[PATCH v2] power: reset: at91-shdwc: add new shutdown controller driver

[Nicolas Ferre]

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 v2:
- add MODULE_DEVICE_TABLE as advised by Sebastian Reichel
- review indentation and braces to correct errors pointed out by checkpatch

 drivers/power/reset/Kconfig      |   8 ++
 drivers/power/reset/Makefile     |   1 +
 drivers/power/reset/at91-shdwc.c | 263 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 272 insertions(+)
 create mode 100644 drivers/power/reset/at91-shdwc.c

diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 5a0189bf19bb..7f52bc938795 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_SHDWC
+	bool "Atmel AT91 shutdown controller driver"
+	depends on ARCH_AT91
+	default SOC_SAMA5
+	help
+	  This driver supports poweroff 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..6b9020ed3fb7 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_SHDWC) += at91-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-shdwc.c b/drivers/power/reset/at91-shdwc.c
new file mode 100644
index 000000000000..433824375243
--- /dev/null
+++ b/drivers/power/reset/at91-shdwc.c
@@ -0,0 +1,263 @@
+/*
+ * Atmel Shutdown Controller (SHDWC) driver
+ *
+ * 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/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		(0xa5 << 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 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)
+{
+	BUG_ON(!at91_shdwc);
+
+	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;
+	const char *pm;
+	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_string(cnp, "atmel,wakeup-type", &pm)) {
+			if (!strcasecmp(pm, "high"))
+				/*
+				 * only add a type if "high" is specified. Low
+				 * is the default.
+				 */
+				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, "atmel,shdwc-debouncer", &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 at91_shdwc_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	const struct of_device_id *match;
+
+	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);
+	if (match != NULL)
+		at91_shdwc->cfg = (struct shdwc_config *)(match->data);
+	else
+		return -ENODATA;
+
+	at91_wakeup_status(pdev);
+
+	at91_shdwc_dt_configure(pdev);
+
+	pm_power_off = at91_poweroff;
+
+	return 0;
+}
+
+static struct platform_driver at91_shdwc_driver = {
+	.probe = at91_shdwc_probe,
+	.driver = {
+		.name = "at91-shdwc",
+		.of_match_table = at91_shdwc_of_match,
+	},
+};
+module_platform_driver(at91_shdwc_driver);
+
+MODULE_AUTHOR("Nicolas Ferre <nicolas.ferre@atmel.com>");
+MODULE_DESCRIPTION("Atmel shutdown controller driver");
+MODULE_LICENSE("GPL v2");
-- 
2.1.3

[PATCH v2] power: reset: at91-shdwc: add new shutdown controller driver

[Alexandre Belloni]

On 22/09/2015 at 17:57:52 +0200, Nicolas Ferre wrote :
> +config POWER_RESET_AT91_SHDWC

Maybe we should start numbering, at91-poweroff is already a driver for
an shdwc.

> +#define SLOW_CLOCK_FREQ	32768
> +

The slow clock is an input to the shdwc, then you have to get it,
prepare and enable it. The you could use clk_get_rate.
By duplicating the driver, you are repeating mistakes from the past ;)


> +static void at91_poweroff(void)
> +{
> +	BUG_ON(!at91_shdwc);

Is that condition even possible?

> +
> +	writel(AT91_SHDW_KEY | AT91_SHDW_SHDW,
> +			at91_shdwc->at91_shdwc_base + AT91_SHDW_CR);

This is not properly aligned.

> +}
> +
> +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);
ditto


> +		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;
> +	const char *pm;
> +	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_string(cnp, "atmel,wakeup-type", &pm)) {
> +			if (!strcasecmp(pm, "high"))
> +				/*
> +				 * only add a type if "high" is specified. Low
> +				 * is the default.
> +				 */
> +				wuir |= AT91_SHDW_WKUPT(wk_input);
> +		}
> +		dev_dbg(&pdev->dev, "%s: (child %d) wuir = %#x\n",
> +						__func__, wk_input, wuir);

ditto

> +static int at91_shdwc_probe(struct platform_device *pdev)
> +{
> +	struct resource *res;
> +	const struct of_device_id *match;
> +
> +	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);
> +	if (match != NULL)

match will never be NULL, else you wouldn't be probed. You can remove that test.

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

[PATCH v2] power: reset: at91-shdwc: add new shutdown controller driver

[Nicolas Ferre]

Le 24/09/2015 13:06, Alexandre Belloni a ?crit :
> On 22/09/2015 at 17:57:52 +0200, Nicolas Ferre wrote :
>> +config POWER_RESET_AT91_SHDWC
> 
> Maybe we should start numbering, at91-poweroff is already a driver for
> an shdwc.
> 
>> +#define SLOW_CLOCK_FREQ	32768
>> +
> 
> The slow clock is an input to the shdwc, then you have to get it,
> prepare and enable it. The you could use clk_get_rate.

Okay, sure: I modify the driver to take your enhancements into account.

> By duplicating the driver, you are repeating mistakes from the past ;)

Hey! look at the common parts that these drivers would share if it was
merged and you would realize that it was not worth the effort: I tried
and judged it was completely pointless.

>> +static void at91_poweroff(void)
>> +{
>> +	BUG_ON(!at91_shdwc);
> 
> Is that condition even possible?

No it's not. I remove it.

> 
>> +
>> +	writel(AT91_SHDW_KEY | AT91_SHDW_SHDW,
>> +			at91_shdwc->at91_shdwc_base + AT91_SHDW_CR);
> 
> This is not properly aligned.

Why? I prefer it like this and the second line doesn't cross the 80
column so I presume that it's valid.

> 
>> +}
>> +
>> +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);
> ditto
> 
> 
>> +		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;
>> +	const char *pm;
>> +	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_string(cnp, "atmel,wakeup-type", &pm)) {
>> +			if (!strcasecmp(pm, "high"))
>> +				/*
>> +				 * only add a type if "high" is specified. Low
>> +				 * is the default.
>> +				 */
>> +				wuir |= AT91_SHDW_WKUPT(wk_input);
>> +		}
>> +		dev_dbg(&pdev->dev, "%s: (child %d) wuir = %#x\n",
>> +						__func__, wk_input, wuir);
> 
> ditto
> 
>> +static int at91_shdwc_probe(struct platform_device *pdev)
>> +{
>> +	struct resource *res;
>> +	const struct of_device_id *match;
>> +
>> +	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);
>> +	if (match != NULL)
> 
> match will never be NULL, else you wouldn't be probed. You can remove that test.

I'll remove this and repost the driver as v3.

Thanks, bye,
-- 
Nicolas Ferre