mfd: twl4030-power: Add generic reset configuration

The twl4030 PMIC needs to be configured properly for things like
warm reset and deeper idle states so the PMIC manages the regulators
properly based on the hardware triggers from the SoC. Earlier
we have configured twl4030 using platform data, but we want to
do it for device tree based booting also.

In some cases configuring twl4030 is needed for things to work.
For example, when rebooting an OMAP3530 at 125 MHz, it hangs.
With this patch, TWL4030 will be reset when a warm reset occures,
and OMAP3530 does not hang on reboot.

Let's add device tree support and configure things for warm reset
as the default when compatible = "ti,twl4030-power". More
complicated configurations can be added to the driver based on
other compatible flags.

Note we now also make the pdata const like it should be.
This allows use it for match->data with the device tree
related functions.

Based on earlier patch by Matthias Brugger <matthias.bgg@gmail.com>
and Lesly A M <leslyam@ti.com>.

Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 96 insertions, 13 deletions

diff --git a/drivers/mfd/twl4030-power.c b/drivers/mfd/twl4030-power.c
index 0b037dc..cb5b0cb 100644
--- a/drivers/mfd/twl4030-power.c
+++ b/drivers/mfd/twl4030-power.c
@@ -29,6 +29,7 @@
 #include <linux/i2c/twl.h>
 #include <linux/platform_device.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 
 #include <asm/mach-types.h>
 
@@ -128,6 +129,40 @@ static u8 res_config_addrs[] = {
 	[RES_MAIN_REF]	= 0x94,
 };
 
+/*
+ * Usable values for .remap_sleep and .remap_off
+ * Based on table "5.3.3 Resource Operating modes"
+ */
+enum {
+	TWL_REMAP_OFF = 0,
+	TWL_REMAP_SLEEP = 8,
+	TWL_REMAP_ACTIVE = 9,
+};
+
+/*
+ * Macros to configure the PM register states for various resources.
+ * Note that we can make MSG_SINGULAR etc private to this driver once
+ * omap3 has been made DT only.
+ */
+#define TWL_DFLT_DELAY		2	/* typically 2 32 KiHz cycles */
+#define TWL_RESOURCE_SET(res, state)					\
+	{ MSG_SINGULAR(DEV_GRP_NULL, (res), (state)), TWL_DFLT_DELAY }
+#define TWL_RESOURCE_ON(res)	TWL_RESOURCE_SET(res, RES_STATE_ACTIVE)
+#define TWL_RESOURCE_OFF(res)	TWL_RESOURCE_SET(res, RES_STATE_OFF)
+#define TWL_RESOURCE_RESET(res)	TWL_RESOURCE_SET(res, RES_STATE_WRST)
+/*
+ * It seems that type1 and type2 is just the resource init order
+ * number for the type1 and type2 group.
+ */
+#define TWL_RESOURCE_GROUP_RESET(group, type1, type2)			\
+	{ MSG_BROADCAST(DEV_GRP_NULL, (group), (type1), (type2),	\
+		RES_STATE_WRST), TWL_DFLT_DELAY }
+#define TWL_REMAP_SLEEP(res, devgrp, typ, typ2)				\
+	{ .resource = (res), .devgroup = (devgrp),			\
+	  .type = (typ), .type2 = (typ2),				\
+	  .remap_off = TWL_REMAP_OFF,					\
+	  .remap_sleep = TWL_REMAP_SLEEP, }
+
 static int twl4030_write_script_byte(u8 address, u8 byte)
 {
 	int err;
@@ -502,7 +537,8 @@ int twl4030_remove_script(u8 flags)
 	return err;
 }
 
-static int twl4030_power_configure_scripts(struct twl4030_power_data *pdata)
+static int
+twl4030_power_configure_scripts(const struct twl4030_power_data *pdata)
 {
 	int err;
 	int i;
@@ -518,7 +554,8 @@ static int twl4030_power_configure_scripts(struct twl4030_power_data *pdata)
 	return 0;
 }
 
-static int twl4030_power_configure_resources(struct twl4030_power_data *pdata)
+static int
+twl4030_power_configure_resources(const struct twl4030_power_data *pdata)
 {
 	struct twl4030_resconfig *resconfig = pdata->resource_config;
 	int err;
@@ -550,7 +587,7 @@ void twl4030_power_off(void)
 		pr_err("TWL4030 Unable to power off\n");
 }
 
-static bool twl4030_power_use_poweroff(struct twl4030_power_data *pdata,
+static bool twl4030_power_use_poweroff(const struct twl4030_power_data *pdata,
 					struct device_node *node)
 {
 	if (pdata && pdata->use_poweroff)
@@ -562,10 +599,60 @@ static bool twl4030_power_use_poweroff(struct twl4030_power_data *pdata,
 	return false;
 }
 
+#ifdef CONFIG_OF
+
+/* Generic warm reset configuration for omap3 */
+
+static struct twl4030_ins omap3_wrst_seq[] = {
+	TWL_RESOURCE_OFF(RES_NRES_PWRON),
+	TWL_RESOURCE_OFF(RES_RESET),
+	TWL_RESOURCE_RESET(RES_MAIN_REF),
+	TWL_RESOURCE_GROUP_RESET(RES_GRP_ALL, RES_TYPE_R0, RES_TYPE2_R2),
+	TWL_RESOURCE_RESET(RES_VUSB_3V1),
+	TWL_RESOURCE_GROUP_RESET(RES_GRP_ALL, RES_TYPE_R0, RES_TYPE2_R1),
+	TWL_RESOURCE_GROUP_RESET(RES_GRP_RC, RES_TYPE_ALL, RES_TYPE2_R0),
+	TWL_RESOURCE_ON(RES_RESET),
+	TWL_RESOURCE_ON(RES_NRES_PWRON),
+};
+
+static struct twl4030_script omap3_wrst_script = {
+	.script	= omap3_wrst_seq,
+	.size	= ARRAY_SIZE(omap3_wrst_seq),
+	.flags	= TWL4030_WRST_SCRIPT,
+};
+
+static struct twl4030_script *omap3_reset_scripts[] = {
+	&omap3_wrst_script,
+};
+
+static struct twl4030_resconfig omap3_rconfig[] = {
+	TWL_REMAP_SLEEP(RES_HFCLKOUT, DEV_GRP_P3, -1, -1),
+	TWL_REMAP_SLEEP(RES_VDD1, DEV_GRP_P1, -1, -1),
+	TWL_REMAP_SLEEP(RES_VDD2, DEV_GRP_P1, -1, -1),
+	{ 0, 0 },
+};
+
+static struct twl4030_power_data omap3_reset = {
+	.scripts		= omap3_reset_scripts,
+	.num			= ARRAY_SIZE(omap3_reset_scripts),
+	.resource_config	= omap3_rconfig,
+};
+
+static struct of_device_id twl4030_power_of_match[] = {
+	{
+		.compatible = "ti,twl4030-power-reset",
+		.data = &omap3_reset,
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, twl4030_power_of_match);
+#endif	/* CONFIG_OF */
+
 static int twl4030_power_probe(struct platform_device *pdev)
 {
-	struct twl4030_power_data *pdata = dev_get_platdata(&pdev->dev);
+	const struct twl4030_power_data *pdata = dev_get_platdata(&pdev->dev);
 	struct device_node *node = pdev->dev.of_node;
+	const struct of_device_id *match;
 	int err = 0;
 	int err2 = 0;
 	u8 val;
@@ -586,8 +673,12 @@ static int twl4030_power_probe(struct platform_device *pdev)
 		return err;
 	}
 
+	match = of_match_device(of_match_ptr(twl4030_power_of_match),
+				&pdev->dev);
+	if (match && match->data)
+		pdata = match->data;
+
 	if (pdata) {
-		/* TODO: convert to device tree */
 		err = twl4030_power_configure_scripts(pdata);
 		if (err) {
 			pr_err("TWL4030 failed to load scripts\n");
@@ -637,14 +728,6 @@ static int twl4030_power_remove(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_OF
-static const struct of_device_id twl4030_power_of_match[] = {
-	{.compatible = "ti,twl4030-power", },
-	{ },
-};
-MODULE_DEVICE_TABLE(of, twl4030_power_of_match);
-#endif
-
 static struct platform_driver twl4030_power_driver = {
 	.driver = {
 		.name	= "twl4030_power",