mfd: twl4030-power: Start transition to DT

Support for loading twl4030-power module via devicetree.
For now, when booting with a DT, only the poweroff callback
feature is supported through the ti,use_poweroff property.

Signed-off-by: Florian Vaussard <florian.vaussard@epfl.ch>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

2 files changed, 66 insertions, 7 deletions

diff --git a/Documentation/devicetree/bindings/mfd/twl4030-power.txt b/Documentation/devicetree/bindings/mfd/twl4030-power.txt
new file mode 100644
index 000000000000..8e15ec35ac99
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/twl4030-power.txt
@@ -0,0 +1,28 @@
+Texas Instruments TWL family (twl4030) reset and power management module
+
+The power management module inside the TWL family provides several facilities
+to control the power resources, including power scripts. For now, the
+binding only supports the complete shutdown of the system after poweroff.
+
+Required properties:
+- compatible : must be "ti,twl4030-power"
+
+Optional properties:
+- ti,use_poweroff: With this flag, the chip will initiates an ACTIVE-to-OFF or
+                   SLEEP-to-OFF transition when the system poweroffs.
+
+Example:
+&i2c1 {
+        clock-frequency = <2600000>;
+
+        twl: twl@48 {
+                reg = <0x48>;
+                interrupts = <7>; /* SYS_NIRQ cascaded to intc */
+                interrupt-parent = <&intc>;
+
+                twl_power: power {
+                        compatible = "ti,twl4030-power";
+                        ti,use_poweroff;
+                };
+        };
+};
diff --git a/drivers/mfd/twl4030-power.c b/drivers/mfd/twl4030-power.c
index d36622d0f98a..5b2848280f4b 100644
--- a/drivers/mfd/twl4030-power.c
+++ b/drivers/mfd/twl4030-power.c
@@ -28,6 +28,7 @@
 #include <linux/pm.h>
 #include <linux/i2c/twl.h>
 #include <linux/platform_device.h>
+#include <linux/of.h>
 
 #include <asm/mach-types.h>
 
@@ -540,12 +541,30 @@ void twl4030_power_off(void)
                 pr_err("TWL4030 Unable to power off\n");
 }
 
+static bool twl4030_power_use_poweroff(struct twl4030_power_data *pdata,
+                                        struct device_node *node)
+{
+        if (pdata && pdata->use_poweroff)
+                return true;
+
+        if (of_property_read_bool(node, "ti,use_poweroff"))
+                return true;
+
+        return false;
+}
+
 int twl4030_power_probe(struct platform_device *pdev)
 {
         struct twl4030_power_data *pdata = pdev->dev.platform_data;
+        struct device_node *node = pdev->dev.of_node;
         int err = 0;
         u8 val;
 
+        if (!pdata && !node) {
+                dev_err(&pdev->dev, "Platform data is missing\n");
+                return -EINVAL;
+        }
+
         err = twl_i2c_write_u8(TWL_MODULE_PM_MASTER, TWL4030_PM_MASTER_KEY_CFG1,
                                TWL4030_PM_MASTER_PROTECT_KEY);
         if (err)
@@ -556,15 +575,18 @@ int twl4030_power_probe(struct platform_device *pdev)
         if (err)
                 goto unlock;
 
-        err = twl4030_power_configure_scripts(pdata);
-        if (err)
-                goto load;
-        err = twl4030_power_configure_resources(pdata);
-        if (err)
-                goto resource;
+        if (pdata) {
+                /* TODO: convert to device tree */
+                err = twl4030_power_configure_scripts(pdata);
+                if (err)
+                        goto load;
+                err = twl4030_power_configure_resources(pdata);
+                if (err)
+                        goto resource;
+        }
 
         /* Board has to be wired properly to use this feature */
-        if (pdata->use_poweroff && !pm_power_off) {
+        if (twl4030_power_use_poweroff(pdata, node) && !pm_power_off) {
                 /* Default for SEQ_OFFSYNC is set, lets ensure this */
                 err = twl_i2c_read_u8(TWL_MODULE_PM_MASTER, &val,
                                       TWL4030_PM_MASTER_CFG_P123_TRANSITION);
@@ -610,10 +632,19 @@ 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",
                 .owner  = THIS_MODULE,
+                .of_match_table = of_match_ptr(twl4030_power_of_match),
         },
         .probe          = twl4030_power_probe,
         .remove         = twl4030_power_remove,