[U-Boot] [PATCH v2] power: extend prefix match to regulator-name property

Mon Oct 23 13:31:42 UTC 2017

On 20.10.2017 15:34, Jaehoon Chung wrote:
> On 10/18/2017 06:39 PM, Felix Brack wrote:
>> This patch extends pmic_bind_children prefix matching. In addition to
>> the node name the property regulator-name is used while trying to match
>> prefixes. This allows assigning different drivers to regulator nodes
>> named regulator at 1 and regulator at 10 for example.
>> I have discarded the idea of using other properties then regulator-name
>> as I do not see any benefit in using property compatible or even
>> regulator-compatible. Of course I am open to change this if there are
>> good reasons to do so.
>>
>> Signed-off-by: Felix Brack <fb at ltec.ch>
>> ---
>>
>> Changes in v2:
>> - add documentation
>> - add a regulator to the sandbox for testing
>> - extend the test for the new sandbox regulator
>>
>>  arch/sandbox/dts/sandbox_pmic.dtsi               |  6 ++++++
>>  doc/device-tree-bindings/regulator/regulator.txt | 16 ++++++++++++++--
>>  drivers/power/pmic/pmic-uclass.c                 | 15 +++++++++++++--
>>  include/power/sandbox_pmic.h                     |  5 ++++-
>>  test/dm/regulator.c                              |  2 ++
>>  5 files changed, 39 insertions(+), 5 deletions(-)
>>
>> diff --git a/arch/sandbox/dts/sandbox_pmic.dtsi b/arch/sandbox/dts/sandbox_pmic.dtsi
>> index ce261b9..acb4799 100644
>> --- a/arch/sandbox/dts/sandbox_pmic.dtsi
>> +++ b/arch/sandbox/dts/sandbox_pmic.dtsi
>> @@ -75,4 +75,10 @@
>>  		regulator-min-microvolt = <3300000>;
>>  		regulator-max-microvolt = <3300000>;
>>  	};
>> +
>> +	no_match_by_nodename {
>> +		regulator-name = "buck_SUPPLY_1.5V";
>> +		regulator-min-microvolt = <1500000>;
>> +		regulator-max-microvolt = <1500000>;
>> +	};
>>  };
>> diff --git a/doc/device-tree-bindings/regulator/regulator.txt b/doc/device-tree-bindings/regulator/regulator.txt
>> index 918711e..65b69c4 100644
>> --- a/doc/device-tree-bindings/regulator/regulator.txt
>> +++ b/doc/device-tree-bindings/regulator/regulator.txt
>> @@ -2,7 +2,8 @@ Voltage/Current regulator
>>  
>>  Binding:
>>  The regulator devices don't use the "compatible" property. The binding is done
>> -by the prefix of regulator node's name. Usually the pmic I/O driver will provide
>> +by the prefix of regulator node's name, or, if this fails, by the prefix of the
>> +regulator's "regulator-name" property. Usually the pmic I/O driver will provide
>>  the array of 'struct pmic_child_info' with the prefixes and compatible drivers.
>>  The bind is done by calling function: pmic_bind_childs().
>>  Example drivers:
>> @@ -15,8 +16,19 @@ For the node name e.g.: "prefix[:alpha:]num { ... }":
>>  
>>  Example the prefix "ldo" will pass for: "ldo1", "ldo at 1", "ldoreg at 1, ...
>>  
>> +Binding by means of the node's name is preferred. However if the node names
>> +would produce ambiguous prefixes (like "regulator at 1" and "regualtor at 11") and you
>> +can't or do not want to change them then binding against the "regulator-name"
>> +property is possible. The syntax for the prefix of the "regulator-name" property
>> +is the same as the one for the regulator's node name.
>> +Use case: a regulator named "regulator at 1" to be bound to a driver named
>> +"LDO_DRV" and a regulator named "regualator at 11" to be bound to an other driver
>> +named "BOOST_DRV". Using prefix "regualtor at 1" for driver matching would load
>> +the same driver for both regulators, hence the prefix is ambiguous.
>> +
>>  Optional properties:
>> -- regulator-name: a string, required by the regulator uclass
>> +- regulator-name: a string, required by the regulator uclass, used for driver
>> +                  binding if binding by node's name prefix fails
>>  - regulator-min-microvolt: a minimum allowed Voltage value
>>  - regulator-max-microvolt: a maximum allowed Voltage value
>>  - regulator-min-microamp: a minimum allowed Current value
>> diff --git a/drivers/power/pmic/pmic-uclass.c b/drivers/power/pmic/pmic-uclass.c
>> index 64964e4..5a034f0 100644
>> --- a/drivers/power/pmic/pmic-uclass.c
>> +++ b/drivers/power/pmic/pmic-uclass.c
>> @@ -26,6 +26,7 @@ int pmic_bind_children(struct udevice *pmic, ofnode parent,
>>  	struct driver *drv;
>>  	struct udevice *child;
>>  	const char *node_name;
>> +	const char *reg_name;
>>  	int bind_count = 0;
>>  	ofnode node;
>>  	int prefix_len;
>> @@ -44,8 +45,18 @@ int pmic_bind_children(struct udevice *pmic, ofnode parent,
>>  			debug("  - compatible prefix: '%s'\n", info->prefix);
>>  
>>  			prefix_len = strlen(info->prefix);
>> -			if (strncmp(info->prefix, node_name, prefix_len))
>> -				continue;
>> +			if (strncmp(info->prefix, node_name, prefix_len)) {
>> +				reg_name = ofnode_read_string(node,
>> +							      "regulator-name");
>> +				if (reg_name) {
>> +					if (strncmp(info->prefix, reg_name,
>> +						    prefix_len)) {
>> +						continue;
>> +					}
>> +				} else {
>> +					continue;
>> +				}The below code is more readable?
> 
> if (!reg_name)
> 	continue;
> 
> if (strncmp())
> 	continue;
> 
> ...
> 
> how about?
>
Agreed. Looks much better and is simpler to read. If somebody insists on
this modification that's fine with me and I will present a v3 patch.

> 
>> +			}
>>  
>>  			drv = lists_driver_lookup_name(info->driver);
>>  			if (!drv) {
>> diff --git a/include/power/sandbox_pmic.h b/include/power/sandbox_pmic.h
>> index 7fdbfb9..da2c296 100644
>> --- a/include/power/sandbox_pmic.h
>> +++ b/include/power/sandbox_pmic.h
>> @@ -13,7 +13,7 @@
>>  #define SANDBOX_BUCK_DRIVER		"sandbox_buck"
>>  #define SANDBOX_OF_BUCK_PREFIX		"buck"
>>  
>> -#define SANDBOX_BUCK_COUNT	2
>> +#define SANDBOX_BUCK_COUNT	3
>>  #define SANDBOX_LDO_COUNT	2
>>  /*
>>   * Sandbox PMIC registers:
>> @@ -114,6 +114,9 @@ enum {
>>  #define SANDBOX_LDO1_PLATNAME	"VDD_EMMC_1.8V"
>>  #define SANDBOX_LDO2_DEVNAME	"ldo2"
>>  #define SANDBOX_LDO2_PLATNAME	"VDD_LCD_3.3V"
>> +/* BUCK3: for testing fallback regulator prefix matching during bind */
>> +#define SANDBOX_BUCK3_DEVNAME	"no_match_by_nodename"
>> +#define SANDBOX_BUCK3_PLATNAME	"buck_SUPPLY_1.5V"
> 
> These defined might be located on above point. (SANDBOX_BUCK2_xxxx)
>
Yes of course. But the idea of putting them here is to emphasize the
special name due to binding against regulator-name property, kind of
separating this BUCK regulator from 'normal' BUCK regulators.

> Best Regards,
> Jaehoon Chung
> 
>>  
>>  /*
>>   * Expected regulators setup after call of:
>> diff --git a/test/dm/regulator.c b/test/dm/regulator.c
>> index 3d0056f..395381d 100644
>> --- a/test/dm/regulator.c
>> +++ b/test/dm/regulator.c
>> @@ -27,6 +27,7 @@ DECLARE_GLOBAL_DATA_PTR;
>>  enum {
>>  	BUCK1,
>>  	BUCK2,
>> +	BUCK3,
>>  	LDO1,
>>  	LDO2,
>>  	OUTPUT_COUNT,
>> @@ -42,6 +43,7 @@ static const char *regulator_names[OUTPUT_COUNT][OUTPUT_NAME_COUNT] = {
>>  	/* devname, platname */
>>  	{ SANDBOX_BUCK1_DEVNAME, SANDBOX_BUCK1_PLATNAME },
>>  	{ SANDBOX_BUCK2_DEVNAME, SANDBOX_BUCK2_PLATNAME },
>> +	{ SANDBOX_BUCK3_DEVNAME, SANDBOX_BUCK3_PLATNAME },
>>  	{ SANDBOX_LDO1_DEVNAME, SANDBOX_LDO1_PLATNAME},
>>  	{ SANDBOX_LDO2_DEVNAME, SANDBOX_LDO2_PLATNAME},
>>  };
>>
> 

regards, Felix