hwmon: (ltc2978) Add regulator support

Add simple on/off regulator support for ltc2978 and
other pmbus parts supported by the ltc2978 driver.

Signed-off-by: Alan Tull <atull@opensource.altera.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

2 files changed, 47 insertions, 3 deletions

diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 6e1e4935fc62..a674cd83a4e2 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -47,15 +47,22 @@ config SENSORS_LM25066
           be called lm25066.
 
 config SENSORS_LTC2978
-        tristate "Linear Technologies LTC2974, LTC2978, LTC3880, and LTC3883"
+        tristate "Linear Technologies LTC2978 and compatibles"
         default n
         help
           If you say yes here you get hardware monitoring support for Linear
-          Technology LTC2974, LTC2978, LTC3880, and LTC3883.
+          Technology LTC2974, LTC2977, LTC2978, LTC3880, LTC3883, and LTM4676.
 
           This driver can also be built as a module. If so, the module will
           be called ltc2978.
 
+config SENSORS_LTC2978_REGULATOR
+        boolean "Regulator support for LTC2978 and compatibles"
+        depends on SENSORS_LTC2978 && REGULATOR
+        help
+          If you say yes here you get regulator support for Linear
+          Technology LTC2974, LTC2977, LTC2978, LTC3880, LTC3883, and LTM4676.
+
 config SENSORS_MAX16064
         tristate "Maxim MAX16064"
         default n
diff --git a/drivers/hwmon/pmbus/ltc2978.c b/drivers/hwmon/pmbus/ltc2978.c
index e24ed521051a..0835050ec245 100644
--- a/drivers/hwmon/pmbus/ltc2978.c
+++ b/drivers/hwmon/pmbus/ltc2978.c
@@ -22,6 +22,7 @@
 #include <linux/err.h>
 #include <linux/slab.h>
 #include <linux/i2c.h>
+#include <linux/regulator/driver.h>
 #include "pmbus.h"
 
 enum chips { ltc2974, ltc2977, ltc2978, ltc3880, ltc3883, ltm4676 };
@@ -374,6 +375,19 @@ static const struct i2c_device_id ltc2978_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, ltc2978_id);
 
+#if IS_ENABLED(CONFIG_SENSORS_LTC2978_REGULATOR)
+static const struct regulator_desc ltc2978_reg_desc[] = {
+        PMBUS_REGULATOR("vout", 0),
+        PMBUS_REGULATOR("vout", 1),
+        PMBUS_REGULATOR("vout", 2),
+        PMBUS_REGULATOR("vout", 3),
+        PMBUS_REGULATOR("vout", 4),
+        PMBUS_REGULATOR("vout", 5),
+        PMBUS_REGULATOR("vout", 6),
+        PMBUS_REGULATOR("vout", 7),
+};
+#endif /* CONFIG_SENSORS_LTC2978_REGULATOR */
+
 static int ltc2978_probe(struct i2c_client *client,
                          const struct i2c_device_id *id)
 {
@@ -487,13 +501,36 @@ static int ltc2978_probe(struct i2c_client *client,
         default:
                 return -ENODEV;
         }
+
+#if IS_ENABLED(CONFIG_SENSORS_LTC2978_REGULATOR)
+        info->num_regulators = info->pages;
+        info->reg_desc = ltc2978_reg_desc;
+        if (info->num_regulators > ARRAY_SIZE(ltc2978_reg_desc)) {
+                dev_err(&client->dev, "num_regulators too large!");
+                info->num_regulators = ARRAY_SIZE(ltc2978_reg_desc);
+        }
+#endif
+
         return pmbus_do_probe(client, id, info);
 }
 
-/* This is the driver that will be inserted */
+#ifdef CONFIG_OF
+static const struct of_device_id ltc2978_of_match[] = {
+        { .compatible = "lltc,ltc2974" },
+        { .compatible = "lltc,ltc2977" },
+        { .compatible = "lltc,ltc2978" },
+        { .compatible = "lltc,ltc3880" },
+        { .compatible = "lltc,ltc3883" },
+        { .compatible = "lltc,ltm4676" },
+        { }
+};
+MODULE_DEVICE_TABLE(of, ltc2978_of_match);
+#endif
+
 static struct i2c_driver ltc2978_driver = {
         .driver = {
                    .name = "ltc2978",
+                   .of_match_table = of_match_ptr(ltc2978_of_match),
                    },
         .probe = ltc2978_probe,
         .remove = pmbus_do_remove,