Re: [PATCH 2/2] regulator: userspace-consumer: Multiple regulators
From: Naresh Solanki
Date: Thu Apr 20 2023 - 08:28:03 EST
Hi Zev,
On 20-04-2023 04:27 pm, Zev Weiss wrote:
On Thu, Apr 20, 2023 at 01:46:14AM PDT, Naresh Solanki wrote:
Hi Zev,
On 20-04-2023 05:32 am, Zev Weiss wrote:
On Tue, Apr 18, 2023 at 07:50:51AM PDT, Naresh Solanki wrote:
Use property regulator-supplies to determine all regulator
supplies.
This is useful in case of a connector having 2 or more supplies.
Example: PCIe connector on mainboard can be powered by 12V & 3.3V
suplies.
Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
---
drivers/regulator/userspace-consumer.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)
diff --git a/drivers/regulator/userspace-consumer.c
b/drivers/regulator/userspace-consumer.c
index 97f075ed68c9..0bb49547b926 100644
--- a/drivers/regulator/userspace-consumer.c
+++ b/drivers/regulator/userspace-consumer.c
@@ -120,7 +120,10 @@ static int
regulator_userspace_consumer_probe(struct platform_device *pdev)
struct regulator_userspace_consumer_data tmpdata;
struct regulator_userspace_consumer_data *pdata;
struct userspace_consumer_data *drvdata;
- int ret;
+ struct device_node *np = pdev->dev.of_node;
+ struct property *prop;
+ const char *supply;
+ int ret, count = 0;
pdata = dev_get_platdata(&pdev->dev);
if (!pdata) {
@@ -131,11 +134,19 @@ static int
regulator_userspace_consumer_probe(struct platform_device *pdev)
memset(pdata, 0, sizeof(*pdata));
pdata->no_autoswitch = true;
- pdata->num_supplies = 1;
- pdata->supplies = devm_kzalloc(&pdev->dev,
sizeof(*pdata->supplies), GFP_KERNEL);
+ pdata->num_supplies = of_property_count_strings(np,
"regulator-supplies");
+ if (pdata->num_supplies < 0) {
+ dev_err(&pdev->dev, "could not parse property
regulator-supplies");
+ return -EINVAL;
+ }
+ pdata->supplies = devm_kzalloc(&pdev->dev,
+ sizeof(*pdata->supplies) *
pdata->num_supplies,
+ GFP_KERNEL);
AFAICT this doesn't appear to implement the "vout" default specified
in the dt-binding patch?
The "regulator-supplies" property will hold the default value of
"vout" unless specified otherwise. As a result, the string enumeration
retrieves the value of "vout" by default, and the "vout-supply"
property is utilized for the regulator.
With the disclaimer that I'm not a DT expert, that's not my
understanding of how DT works. I don't think the 'default' value
specified in the binding forces the fdt to always include that value if
it's not present in the dts (since I'm pretty sure dtc doesn't even look
at the binding to know that a default exists when compiling the dts);
rather, it's information meant to be used by the software implementing
support for that device (e.g. a driver for it) about what value to
assume if the property isn't present in the fdt.
I apologize for the oversight on my part. Upon further testing, I have
discovered that the default did not reflect in the debug prints. I will
address this issue and include the proper fix in the next patchset.
Thank you for bringing this to my attention
Also, since the core of the userspace-consumer driver itself already
supports multiple regulators, it might be nice for the subject line
to mention DT supplies or something a bit more specifically.
Sure. How about 'Support multiple supplies' ?
I meant that it should explicitly mention "DT" (or perhaps "OF"). The
driver's structure has supported multiple supplies since it was first
introduced in 2009, so "Support multiple supplies" sounds like this
commit is adding functionality that was already there. What this patch
is doing is connecting that existing support to the OF support logic so
that it can be used in a device-tree context.
Sure. Will make it something like "Support multiple supplies in DT".
if (!pdata->supplies)
return -ENOMEM;
- pdata->supplies[0].supply = "vout";
+
+ of_property_for_each_string(np, "regulator-supplies", prop,
supply)
+ pdata->supplies[count++].supply = supply;
}
if (pdata->num_supplies < 1) {
--
2.39.1
Regards,
Naresh
Regards,
Naresh