ARM: at91: add Shutdown Controller (SHDWC) DT support

Use a string to specific the wakeup mode to make it more readable.

Add the Real-time Clock Wake-up support too for sam9g45 and sam9x5.
Add AT91_SHDW_CPTWK0_MAX to specific the Max of the Wakeup Counter.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

1 files changed, 77 insertions, 0 deletions

diff --git a/arch/arm/mach-at91/setup.c b/arch/arm/mach-at91/setup.c
index 46d0a56ba82..1083739e306 100644
--- a/arch/arm/mach-at91/setup.c
+++ b/arch/arm/mach-at91/setup.c
@@ -351,10 +351,87 @@ static void at91_dt_ramc(void)
 	of_node_put(np);
 }
 
+static struct of_device_id shdwc_ids[] = {
+	{ .compatible = "atmel,at91sam9260-shdwc", },
+	{ .compatible = "atmel,at91sam9rl-shdwc", },
+	{ .compatible = "atmel,at91sam9x5-shdwc", },
+	{ /*sentinel*/ }
+};
+
+static const char *shdwc_wakeup_modes[] = {
+	[AT91_SHDW_WKMODE0_NONE]	= "none",
+	[AT91_SHDW_WKMODE0_HIGH]	= "high",
+	[AT91_SHDW_WKMODE0_LOW]		= "low",
+	[AT91_SHDW_WKMODE0_ANYLEVEL]	= "any",
+};
+
+const int at91_dtget_shdwc_wakeup_mode(struct device_node *np)
+{
+	const char *pm;
+	int err, i;
+
+	err = of_property_read_string(np, "atmel,wakeup-mode", &pm);
+	if (err < 0)
+		return AT91_SHDW_WKMODE0_ANYLEVEL;
+
+	for (i = 0; i < ARRAY_SIZE(shdwc_wakeup_modes); i++)
+		if (!strcasecmp(pm, shdwc_wakeup_modes[i]))
+			return i;
+
+	return -ENODEV;
+}
+
+static void at91_dt_shdwc(void)
+{
+	struct device_node *np;
+	int wakeup_mode;
+	u32 reg;
+	u32 mode = 0;
+
+	np = of_find_matching_node(NULL, shdwc_ids);
+	if (!np) {
+		pr_debug("AT91: unable to find compatible shutdown (shdwc) conroller node in dtb\n");
+		return;
+	}
+
+	at91_shdwc_base = of_iomap(np, 0);
+	if (!at91_shdwc_base)
+		panic("AT91: unable to map shdwc cpu registers\n");
+
+	wakeup_mode = at91_dtget_shdwc_wakeup_mode(np);
+	if (wakeup_mode < 0) {
+		pr_warn("AT91: shdwc unknown wakeup mode\n");
+		goto end;
+	}
+
+	if (!of_property_read_u32(np, "atmel,wakeup-counter", &reg)) {
+		if (reg > AT91_SHDW_CPTWK0_MAX) {
+			pr_warn("AT91: shdwc wakeup conter 0x%x > 0x%x reduce it to 0x%x\n",
+				reg, AT91_SHDW_CPTWK0_MAX, AT91_SHDW_CPTWK0_MAX);
+			reg = AT91_SHDW_CPTWK0_MAX;
+		}
+		mode |= AT91_SHDW_CPTWK0_(reg);
+	}
+
+	if (of_property_read_bool(np, "atmel,wakeup-rtc-timer"))
+			mode |= AT91_SHDW_RTCWKEN;
+
+	if (of_property_read_bool(np, "atmel,wakeup-rtt-timer"))
+			mode |= AT91_SHDW_RTTWKEN;
+
+	at91_shdwc_write(AT91_SHDW_MR, wakeup_mode | mode);
+
+end:
+	pm_power_off = at91sam9_poweroff;
+
+	of_node_put(np);
+}
+
 void __init at91_dt_initialize(void)
 {
 	at91_dt_rstc();
 	at91_dt_ramc();
+	at91_dt_shdwc();
 
 	/* Init clock subsystem */
 	at91_dt_clock_init();