mfd: TWL5030 version checking in twl-core

Added API to get the TWL5030 Si version from the IDCODE register.
It is used for enabling the workaround for TWL erratum 27.

Signed-off-by: Lesly A M <leslyam@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Cc: David Derrick <dderrick@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 62 insertions, 0 deletions

diff --git a/drivers/mfd/twl-core.c b/drivers/mfd/twl-core.c
index 960b5bed7f52..2bd9e0676bc2 100644
--- a/drivers/mfd/twl-core.c
+++ b/drivers/mfd/twl-core.c
@@ -229,6 +229,9 @@
 /* is driver active, bound to a chip? */
 static bool inuse;
 
+/* TWL IDCODE Register value */
+static u32 twl_idcode;
+
 static unsigned int twl_id;
 unsigned int twl_rev(void)
 {
@@ -487,6 +490,58 @@ EXPORT_SYMBOL(twl_i2c_read_u8);
 
 /*----------------------------------------------------------------------*/
 
+/**
+ * twl_read_idcode_register - API to read the IDCODE register.
+ *
+ * Unlocks the IDCODE register and read the 32 bit value.
+ */
+static int twl_read_idcode_register(void)
+{
+        int err;
+
+        err = twl_i2c_write_u8(TWL4030_MODULE_INTBR, TWL_EEPROM_R_UNLOCK,
+                                                REG_UNLOCK_TEST_REG);
+        if (err) {
+                pr_err("TWL4030 Unable to unlock IDCODE registers -%d\n", err);
+                goto fail;
+        }
+
+        err = twl_i2c_read(TWL4030_MODULE_INTBR, (u8 *)(&twl_idcode),
+                                                REG_IDCODE_7_0, 4);
+        if (err) {
+                pr_err("TWL4030: unable to read IDCODE -%d\n", err);
+                goto fail;
+        }
+
+        err = twl_i2c_write_u8(TWL4030_MODULE_INTBR, 0x0, REG_UNLOCK_TEST_REG);
+        if (err)
+                pr_err("TWL4030 Unable to relock IDCODE registers -%d\n", err);
+fail:
+        return err;
+}
+
+/**
+ * twl_get_type - API to get TWL Si type.
+ *
+ * Api to get the TWL Si type from IDCODE value.
+ */
+int twl_get_type(void)
+{
+        return TWL_SIL_TYPE(twl_idcode);
+}
+EXPORT_SYMBOL_GPL(twl_get_type);
+
+/**
+ * twl_get_version - API to get TWL Si version.
+ *
+ * Api to get the TWL Si version from IDCODE value.
+ */
+int twl_get_version(void)
+{
+        return TWL_SIL_REV(twl_idcode);
+}
+EXPORT_SYMBOL_GPL(twl_get_version);
+
 static struct device *
 add_numbered_child(unsigned chip, const char *name, int num,
                 void *pdata, unsigned pdata_len,
@@ -1014,6 +1069,7 @@ twl_probe(struct i2c_client *client, const struct i2c_device_id *id)
         unsigned                        i;
         struct twl4030_platform_data    *pdata = client->dev.platform_data;
         u8 temp;
+        int ret = 0;
 
         if (!pdata) {
                 dev_dbg(&client->dev, "no platform data?\n");
@@ -1060,6 +1116,12 @@ twl_probe(struct i2c_client *client, const struct i2c_device_id *id)
         /* setup clock framework */
         clocks_init(&client->dev, pdata->clock);
 
+        /* read TWL IDCODE Register */
+        if (twl_id == TWL4030_CLASS_ID) {
+                ret = twl_read_idcode_register();
+                WARN(ret < 0, "Error: reading twl_idcode register value\n");
+        }
+
         /* load power event scripts */
         if (twl_has_power() && pdata->power)
                 twl4030_power_init(pdata->power);