Regulator: lp3972 cleanup
This patch includes below fixes based on Mark's comment.
- Return actual error if i2c_smbus_read_byte_data() fail
- Add spaces around bitwise AND operator(&) to improve readability
- Add comment to explain why we need to update voltage change control register
for LDO1 and LDO5
- Logging the value for diagnostics if chip reported incorrect voltage value
- Add __devinit annotation for setup_regulators()
- Show system control register1 value if the value is mismatched
- Logging the value for diagnostics if failed to detect device
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/drivers/regulator/lp3972.c b/drivers/regulator/lp3972.c
index 0d9b475..e07062f 100644
--- a/drivers/regulator/lp3972.c
+++ b/drivers/regulator/lp3972.c
@@ -192,7 +192,7 @@
return -EIO;
ret = i2c_smbus_read_byte_data(i2c, reg);
if (ret < 0)
- return -EIO;
+ return ret;
*dest = ret;
return 0;
@@ -215,7 +215,7 @@
lp3972_i2c_read(lp3972->i2c, reg, 1, &val);
dev_dbg(lp3972->dev, "reg read 0x%02x -> 0x%02x\n", (int)reg,
- (unsigned)val&0xff);
+ (unsigned)val & 0xff);
mutex_unlock(&lp3972->io_lock);
@@ -234,7 +234,7 @@
if (ret == 0) {
ret = lp3972_i2c_write(lp3972->i2c, reg, 1, &tmp);
dev_dbg(lp3972->dev, "reg write 0x%02x -> 0x%02x\n", (int)reg,
- (unsigned)val&0xff);
+ (unsigned)val & 0xff);
}
mutex_unlock(&lp3972->io_lock);
@@ -320,6 +320,13 @@
if (ret)
return ret;
+ /*
+ * LDO1 and LDO5 support voltage control by either target voltage1
+ * or target voltage2 register.
+ * We use target voltage1 register for LDO1 and LDO5 in this driver.
+ * We need to update voltage change control register(0x20) to enable
+ * LDO1 and LDO5 to change to their programmed target values.
+ */
switch (ldo) {
case LP3972_LDO1:
case LP3972_LDO5:
@@ -401,7 +408,8 @@
val = 1000 * buck_voltage_map[buck][reg];
else {
val = 0;
- dev_warn(&dev->dev, "chip reported incorrect voltage value.\n");
+ dev_warn(&dev->dev, "chip reported incorrect voltage value."
+ " reg = %d\n", reg);
}
return val;
@@ -523,7 +531,7 @@
},
};
-static int setup_regulators(struct lp3972 *lp3972,
+static int __devinit setup_regulators(struct lp3972 *lp3972,
struct lp3972_platform_data *pdata)
{
int i, err;
@@ -584,10 +592,13 @@
/* Detect LP3972 */
ret = lp3972_i2c_read(i2c, LP3972_SYS_CONTROL1_REG, 1, &val);
- if (ret == 0 && (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL)
+ if (ret == 0 &&
+ (val & SYS_CONTROL1_INIT_MASK) != SYS_CONTROL1_INIT_VAL) {
ret = -ENODEV;
+ dev_err(&i2c->dev, "chip reported: val = 0x%x\n", val);
+ }
if (ret < 0) {
- dev_err(&i2c->dev, "failed to detect device\n");
+ dev_err(&i2c->dev, "failed to detect device. ret = %d\n", ret);
goto err_detect;
}