When enabling a fixed regulator, it may take some time to rise to the correct voltage. If we do not delay here then subsequent operations will fail.
Signed-off-by: John Keeping john@metanate.com --- doc/device-tree-bindings/regulator/fixed.txt | 1 + drivers/power/regulator/fixed.c | 10 ++++++++++ 2 files changed, 11 insertions(+)
diff --git a/doc/device-tree-bindings/regulator/fixed.txt b/doc/device-tree-bindings/regulator/fixed.txt index 4ff39b8..8a0d002 100644 --- a/doc/device-tree-bindings/regulator/fixed.txt +++ b/doc/device-tree-bindings/regulator/fixed.txt @@ -10,6 +10,7 @@ Required properties:
Optional properties: - gpio: GPIO to use for enable control +- startup-delay-us: startup time in microseconds - regulator constraints (binding info: regulator.txt)
Other kernel-style properties, are currently not used. diff --git a/drivers/power/regulator/fixed.c b/drivers/power/regulator/fixed.c index d053817..37b8400 100644 --- a/drivers/power/regulator/fixed.c +++ b/drivers/power/regulator/fixed.c @@ -19,6 +19,7 @@ DECLARE_GLOBAL_DATA_PTR;
struct fixed_regulator_platdata { struct gpio_desc gpio; /* GPIO for regulator enable control */ + unsigned int startup_delay_us; };
static int fixed_regulator_ofdata_to_platdata(struct udevice *dev) @@ -42,6 +43,11 @@ static int fixed_regulator_ofdata_to_platdata(struct udevice *dev) if (ret) debug("Fixed regulator gpio - not found! Error: %d", ret);
+ /* Get optional ramp up delay */ + dev_pdata->startup_delay_us = fdtdec_get_uint(gd->fdt_blob, + dev->of_offset, + "startup-delay-us", 0); + return 0; }
@@ -101,6 +107,10 @@ static int fixed_regulator_set_enable(struct udevice *dev, bool enable) enable); return ret; } + + if (enable && dev_pdata->startup_delay_us) + udelay(dev_pdata->startup_delay_us); + return 0; }