2023-02-02 10:10:54

by Maarten Zanders

[permalink] [raw]
Subject: [PATCH v4 0/2] leds: lp55xx: configure internal charge pump

A new option in the devicetree "ti,charge-pump-mode" allows the user to
configure the charge pump in a certain mode. The previous implementation
was "auto" mode, which remains the default.

v1 of the patch implemented a bool to disable the charge pump and had some
issues in the yaml binding.

v2 implemented all options of the charge pump as a string which was too
complex to parse & check.

v3 replaces the string by constants.

v4 resend with changelog (notes) in each patch

Maarten Zanders (2):
dt-bindings: leds-lp55xx: add ti,charge-pump-mode
leds: lp55xx: configure internal charge pump

.../devicetree/bindings/leds/leds-lp55xx.yaml | 8 ++++++++
drivers/leds/leds-lp5521.c | 12 ++++++------
drivers/leds/leds-lp5523.c | 18 +++++++++++++-----
drivers/leds/leds-lp55xx-common.c | 14 ++++++++++++++
drivers/leds/leds-lp8501.c | 8 ++++++--
include/dt-bindings/leds/leds-lp55xx.h | 10 ++++++++++
include/linux/platform_data/leds-lp55xx.h | 3 +++
7 files changed, 60 insertions(+), 13 deletions(-)
create mode 100644 include/dt-bindings/leds/leds-lp55xx.h

--
2.37.3



2023-02-02 10:10:59

by Maarten Zanders

[permalink] [raw]
Subject: [PATCH v4 2/2] leds: lp55xx: configure internal charge pump

The LP55xx range of devices have an internal charge pump which
can (automatically) increase the output voltage towards the
LED's, boosting the output voltage to 4.5V.

Implement this option from the devicetree. When the setting
is not present it will operate in automatic mode as before.

Tested on LP55231. Datasheet analysis shows that LP5521, LP5523
and LP8501 are identical in topology and are modified in the
same way.

Signed-off-by: Maarten Zanders <[email protected]>
---

Notes:
v1: implement as bool to disable charge pump
v2: rewrite to use string configuration, supporting all modes
v3: simplification by replacing string from DTS by constant
v4: added notes

drivers/leds/leds-lp5521.c | 12 ++++++------
drivers/leds/leds-lp5523.c | 18 +++++++++++++-----
drivers/leds/leds-lp55xx-common.c | 14 ++++++++++++++
drivers/leds/leds-lp8501.c | 8 ++++++--
include/linux/platform_data/leds-lp55xx.h | 3 +++
5 files changed, 42 insertions(+), 13 deletions(-)

diff --git a/drivers/leds/leds-lp5521.c b/drivers/leds/leds-lp5521.c
index 19478d9c19a7..76c6b81afb38 100644
--- a/drivers/leds/leds-lp5521.c
+++ b/drivers/leds/leds-lp5521.c
@@ -58,14 +58,11 @@
/* CONFIG register */
#define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */
#define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */
-#define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */
-#define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */
-#define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */
-#define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */
+#define LP5521_CP_MODE_MASK 0x18 /* Charge pump mode */
+#define LP5521_CP_MODE_SHIFT 3
#define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */
#define LP5521_CLK_INT 0x01 /* Internal clock */
-#define LP5521_DEFAULT_CFG \
- (LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)
+#define LP5521_DEFAULT_CFG (LP5521_PWM_HF | LP5521_PWRSAVE_EN)

/* Status */
#define LP5521_EXT_CLK_USED 0x08
@@ -310,6 +307,9 @@ static int lp5521_post_init_device(struct lp55xx_chip *chip)
if (!lp55xx_is_extclk_used(chip))
val |= LP5521_CLK_INT;

+ val |= (chip->pdata->charge_pump_mode << LP5521_CP_MODE_SHIFT) &
+ LP5521_CP_MODE_MASK;
+
ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
if (ret)
return ret;
diff --git a/drivers/leds/leds-lp5523.c b/drivers/leds/leds-lp5523.c
index e08e3de1428d..b5d10d4252e6 100644
--- a/drivers/leds/leds-lp5523.c
+++ b/drivers/leds/leds-lp5523.c
@@ -57,8 +57,12 @@
#define LP5523_AUTO_INC 0x40
#define LP5523_PWR_SAVE 0x20
#define LP5523_PWM_PWR_SAVE 0x04
-#define LP5523_CP_AUTO 0x18
+#define LP5523_CP_MODE_MASK 0x18
+#define LP5523_CP_MODE_SHIFT 3
#define LP5523_AUTO_CLK 0x02
+#define LP5523_DEFAULT_CONFIG \
+ (LP5523_AUTO_INC | LP5523_PWR_SAVE |\
+ LP5523_AUTO_CLK | LP5523_PWM_PWR_SAVE)

#define LP5523_EN_LEDTEST 0x80
#define LP5523_LEDTEST_DONE 0x80
@@ -125,6 +129,7 @@ static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
static int lp5523_post_init_device(struct lp55xx_chip *chip)
{
int ret;
+ int val;

ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
if (ret)
@@ -133,10 +138,13 @@ static int lp5523_post_init_device(struct lp55xx_chip *chip)
/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
usleep_range(1000, 2000);

- ret = lp55xx_write(chip, LP5523_REG_CONFIG,
- LP5523_AUTO_INC | LP5523_PWR_SAVE |
- LP5523_CP_AUTO | LP5523_AUTO_CLK |
- LP5523_PWM_PWR_SAVE);
+ val = LP5523_DEFAULT_CONFIG;
+
+ val |= (chip->pdata->charge_pump_mode << LP5523_CP_MODE_SHIFT) &
+ LP5523_CP_MODE_MASK;
+
+ ret = lp55xx_write(chip, LP5523_REG_CONFIG, val);
+
if (ret)
return ret;

diff --git a/drivers/leds/leds-lp55xx-common.c b/drivers/leds/leds-lp55xx-common.c
index c1940964067a..086033860a6f 100644
--- a/drivers/leds/leds-lp55xx-common.c
+++ b/drivers/leds/leds-lp55xx-common.c
@@ -19,6 +19,8 @@
#include <linux/slab.h>
#include <linux/gpio/consumer.h>

+#include <dt-bindings/leds/leds-lp55xx.h>
+
#include "leds-lp55xx-common.h"

/* External clock rate */
@@ -691,6 +693,18 @@ struct lp55xx_platform_data *lp55xx_of_populate_pdata(struct device *dev,
i++;
}

+ ret = of_property_read_u8(np, "ti,charge-pump-mode",
+ &pdata->charge_pump_mode);
+ if (ret) {
+ pdata->charge_pump_mode = LP55XX_CP_AUTO;
+ } else {
+ if (pdata->charge_pump_mode > LP55XX_CP_AUTO) {
+ dev_err(dev, "invalid charge pump mode %d\n",
+ pdata->charge_pump_mode);
+ return ERR_PTR(-EINVAL);
+ }
+ }
+
of_property_read_string(np, "label", &pdata->label);
of_property_read_u8(np, "clock-mode", &pdata->clock_mode);

diff --git a/drivers/leds/leds-lp8501.c b/drivers/leds/leds-lp8501.c
index ae11a02c0ab2..f0e70e116919 100644
--- a/drivers/leds/leds-lp8501.c
+++ b/drivers/leds/leds-lp8501.c
@@ -53,10 +53,11 @@
#define LP8501_PWM_PSAVE BIT(7)
#define LP8501_AUTO_INC BIT(6)
#define LP8501_PWR_SAVE BIT(5)
-#define LP8501_CP_AUTO 0x18
+#define LP8501_CP_MODE_MASK 0x18
+#define LP8501_CP_MODE_SHIFT 3
#define LP8501_INT_CLK BIT(0)
#define LP8501_DEFAULT_CFG \
- (LP8501_PWM_PSAVE | LP8501_AUTO_INC | LP8501_PWR_SAVE | LP8501_CP_AUTO)
+ (LP8501_PWM_PSAVE | LP8501_AUTO_INC | LP8501_PWR_SAVE)

#define LP8501_REG_RESET 0x3D
#define LP8501_RESET 0xFF
@@ -102,6 +103,9 @@ static int lp8501_post_init_device(struct lp55xx_chip *chip)
if (chip->pdata->clock_mode != LP55XX_CLOCK_EXT)
val |= LP8501_INT_CLK;

+ val |= (chip->pdata->charge_pump_mode << LP8501_CP_MODE_SHIFT) &
+ LP8501_CP_MODE_MASK;
+
ret = lp55xx_write(chip, LP8501_REG_CONFIG, val);
if (ret)
return ret;
diff --git a/include/linux/platform_data/leds-lp55xx.h b/include/linux/platform_data/leds-lp55xx.h
index 3441064713a3..9a738979e1ce 100644
--- a/include/linux/platform_data/leds-lp55xx.h
+++ b/include/linux/platform_data/leds-lp55xx.h
@@ -73,6 +73,9 @@ struct lp55xx_platform_data {
/* Clock configuration */
u8 clock_mode;

+ /* Charge pump mode */
+ u8 charge_pump_mode;
+
/* optional enable GPIO */
struct gpio_desc *enable_gpiod;

--
2.37.3


2023-02-02 10:11:03

by Maarten Zanders

[permalink] [raw]
Subject: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode

Add a binding to configure the internal charge pump for lp55xx.

Signed-off-by: Maarten Zanders <[email protected]>
---

Notes:
v1: implement as bool to disable charge pump
v2: rewrite to use string configuration, supporting all modes
v3: simplification by replacing string option by u8 constant,
removing previous Reviewed-by tags as it's a complete
rewrite of the patch.
v4: added notes

.../devicetree/bindings/leds/leds-lp55xx.yaml | 8 ++++++++
include/dt-bindings/leds/leds-lp55xx.h | 10 ++++++++++
2 files changed, 18 insertions(+)
create mode 100644 include/dt-bindings/leds/leds-lp55xx.h

diff --git a/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml b/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml
index ae607911f1db..22e63d89d770 100644
--- a/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml
+++ b/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml
@@ -66,6 +66,12 @@ properties:
'#size-cells':
const: 0

+ ti,charge-pump-mode:
+ description:
+ Set the operating mode of the internal charge pump as defined in
+ <dt-bindings/leds/leds-lp55xx.h>. Defaults to auto.
+ $ref: /schemas/types.yaml#/definitions/uint8
+
patternProperties:
'^multi-led@[0-8]$':
type: object
@@ -152,6 +158,7 @@ additionalProperties: false
examples:
- |
#include <dt-bindings/leds/common.h>
+ #include <dt-bindings/leds/leds-lp55xx.h>

i2c {
#address-cells = <1>;
@@ -164,6 +171,7 @@ examples:
reg = <0x32>;
clock-mode = /bits/ 8 <2>;
pwr-sel = /bits/ 8 <3>; /* D1~9 connected to VOUT */
+ ti,charge-pump-mode = /bits/ 8 <LP55XX_CP_BYPASS>;

led@0 {
reg = <0>;
diff --git a/include/dt-bindings/leds/leds-lp55xx.h b/include/dt-bindings/leds/leds-lp55xx.h
new file mode 100644
index 000000000000..8f59c1c12dee
--- /dev/null
+++ b/include/dt-bindings/leds/leds-lp55xx.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _DT_BINDINGS_LEDS_LP55XX_H
+#define _DT_BINDINGS_LEDS_LP55XX_H
+
+#define LP55XX_CP_OFF 0
+#define LP55XX_CP_BYPASS 1
+#define LP55XX_CP_BOOST 2
+#define LP55XX_CP_AUTO 3
+
+#endif /* _DT_BINDINGS_LEDS_LP55XX_H */
--
2.37.3


2023-02-02 13:13:39

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode

On 02/02/2023 11:10, Maarten Zanders wrote:
> Add a binding to configure the internal charge pump for lp55xx.
>
> Signed-off-by: Maarten Zanders <[email protected]>
> ---
>
> Notes:
> v1: implement as bool to disable charge pump
> v2: rewrite to use string configuration, supporting all modes
> v3: simplification by replacing string option by u8 constant,
> removing previous Reviewed-by tags as it's a complete
> rewrite of the patch.
> v4: added notes


>
> .../devicetree/bindings/leds/leds-lp55xx.yaml | 8 ++++++++
> include/dt-bindings/leds/leds-lp55xx.h | 10 ++++++++++
> 2 files changed, 18 insertions(+)
> create mode 100644 include/dt-bindings/leds/leds-lp55xx.h
>
> diff --git a/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml b/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml
> index ae607911f1db..22e63d89d770 100644
> --- a/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml
> +++ b/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml
> @@ -66,6 +66,12 @@ properties:
> '#size-cells':
> const: 0
>
> + ti,charge-pump-mode:
> + description:
> + Set the operating mode of the internal charge pump as defined in
> + <dt-bindings/leds/leds-lp55xx.h>. Defaults to auto.
> + $ref: /schemas/types.yaml#/definitions/uint8
> +
> patternProperties:
> '^multi-led@[0-8]$':
> type: object
> @@ -152,6 +158,7 @@ additionalProperties: false
> examples:
> - |
> #include <dt-bindings/leds/common.h>
> + #include <dt-bindings/leds/leds-lp55xx.h>
>
> i2c {
> #address-cells = <1>;
> @@ -164,6 +171,7 @@ examples:
> reg = <0x32>;
> clock-mode = /bits/ 8 <2>;
> pwr-sel = /bits/ 8 <3>; /* D1~9 connected to VOUT */
> + ti,charge-pump-mode = /bits/ 8 <LP55XX_CP_BYPASS>;


No. V2 was correct. What happened here? You got review for v2, but
suddenly entire patch goes into other direction...

Best regards,
Krzysztof


2023-02-02 13:15:18

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode

On 02/02/2023 11:10, Maarten Zanders wrote:
> Add a binding to configure the internal charge pump for lp55xx.
>
> Signed-off-by: Maarten Zanders <[email protected]>



> diff --git a/include/dt-bindings/leds/leds-lp55xx.h b/include/dt-bindings/leds/leds-lp55xx.h
> new file mode 100644
> index 000000000000..8f59c1c12dee
> --- /dev/null
> +++ b/include/dt-bindings/leds/leds-lp55xx.h
> @@ -0,0 +1,10 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef _DT_BINDINGS_LEDS_LP55XX_H
> +#define _DT_BINDINGS_LEDS_LP55XX_H
> +
> +#define LP55XX_CP_OFF 0
> +#define LP55XX_CP_BYPASS 1
> +#define LP55XX_CP_BOOST 2
> +#define LP55XX_CP_AUTO 3

Additionally, these are not used, so it's a dead binding. Drop. Sorry,
this is not the approach you should take.

Best regards,
Krzysztof


2023-02-02 13:35:22

by Maarten Zanders

[permalink] [raw]
Subject: Re: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode

First off, bear with me here, I only recently started upstreaming
patches to kernel. It still feels like navigating an extremely busy
shipping lane... Either way, your feedback is highly valued.

On 2/2/23 14:15, Krzysztof Kozlowski wrote:
>
>> diff --git a/include/dt-bindings/leds/leds-lp55xx.h b/include/dt-bindings/leds/leds-lp55xx.h
>> new file mode 100644
>> index 000000000000..8f59c1c12dee
>> --- /dev/null
>> +++ b/include/dt-bindings/leds/leds-lp55xx.h
>> @@ -0,0 +1,10 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +#ifndef _DT_BINDINGS_LEDS_LP55XX_H
>> +#define _DT_BINDINGS_LEDS_LP55XX_H
>> +
>> +#define LP55XX_CP_OFF 0
>> +#define LP55XX_CP_BYPASS 1
>> +#define LP55XX_CP_BOOST 2
>> +#define LP55XX_CP_AUTO 3
> Additionally, these are not used, so it's a dead binding. Drop. Sorry,
> this is not the approach you should take.
>
> Best regards,
> Krzysztof
>
These definitions are intended to be used in the DTS's, so it seems
normal to me that most of them go unused in the code? What am I missing?

As for the changes v2 > v3, this was based on input I got on v2 from Lee
Jones, maintainer for leds, on the implementation of the parsing of this
option:

>> + pdata->charge_pump_mode = LP55XX_CP_AUTO;
>> + ret = of_property_read_string(np, "ti,charge-pump-mode", &pm);
>> + if (!ret) {
>> + for (cp_mode = LP55XX_CP_OFF;
>> + cp_mode < ARRAY_SIZE(charge_pump_modes);
>> + cp_mode++) {
>> + if (!strcasecmp(pm, charge_pump_modes[cp_mode])) {
>> + pdata->charge_pump_mode = cp_mode;
>> + break;
>> + }
>> + }
>> + }
> A little over-engineered, no?
>
> Why not make the property a numerical value, then simply:
>
> ret = of_property_read_u32(np, "ti,charge-pump-mode", &pdata->charge_pump_mode);
> if (ret)
> data->charge_pump_mode = LP55XX_CP_AUTO;

I found examples of similar configuration options of both types with
other drivers in the kernel tree (ie string & uint8). I can appreciate
both viewpoints but unfortunately cannot comply with both.


Best regards,
Maarten


2023-02-02 13:43:56

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode

On 02/02/2023 14:35, Maarten Zanders wrote:
> First off, bear with me here, I only recently started upstreaming
> patches to kernel. It still feels like navigating an extremely busy
> shipping lane... Either way, your feedback is highly valued.
>
> On 2/2/23 14:15, Krzysztof Kozlowski wrote:
>>
>>> diff --git a/include/dt-bindings/leds/leds-lp55xx.h b/include/dt-bindings/leds/leds-lp55xx.h
>>> new file mode 100644
>>> index 000000000000..8f59c1c12dee
>>> --- /dev/null
>>> +++ b/include/dt-bindings/leds/leds-lp55xx.h
>>> @@ -0,0 +1,10 @@
>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>> +#ifndef _DT_BINDINGS_LEDS_LP55XX_H
>>> +#define _DT_BINDINGS_LEDS_LP55XX_H
>>> +
>>> +#define LP55XX_CP_OFF 0
>>> +#define LP55XX_CP_BYPASS 1
>>> +#define LP55XX_CP_BOOST 2
>>> +#define LP55XX_CP_AUTO 3
>> Additionally, these are not used, so it's a dead binding. Drop. Sorry,
>> this is not the approach you should take.
>>
>> Best regards,
>> Krzysztof
>>
> These definitions are intended to be used in the DTS's, so it seems
> normal to me that most of them go unused in the code? What am I missing?

Bindings mean drivers are using them. Your driver is not using it. It's
a register value, isn't it? Register values are not suitable for
bindings. There is no need for them to be in bindings.

>
> As for the changes v2 > v3, this was based on input I got on v2 from Lee
> Jones, maintainer for leds, on the implementation of the parsing of this
> option:
>
>>> + pdata->charge_pump_mode = LP55XX_CP_AUTO;
>>> + ret = of_property_read_string(np, "ti,charge-pump-mode", &pm);
>>> + if (!ret) {
>>> + for (cp_mode = LP55XX_CP_OFF;
>>> + cp_mode < ARRAY_SIZE(charge_pump_modes);
>>> + cp_mode++) {
>>> + if (!strcasecmp(pm, charge_pump_modes[cp_mode])) {
>>> + pdata->charge_pump_mode = cp_mode;
>>> + break;
>>> + }
>>> + }
>>> + }
>> A little over-engineered, no?
>>
>> Why not make the property a numerical value, then simply:
>>
>> ret = of_property_read_u32(np, "ti,charge-pump-mode", &pdata->charge_pump_mode);
>> if (ret)
>> data->charge_pump_mode = LP55XX_CP_AUTO;
>
> I found examples of similar configuration options of both types with
> other drivers in the kernel tree (ie string & uint8). I can appreciate
> both viewpoints but unfortunately cannot comply with both.

Strings in DTS are usually easier to for humans to read, but it's not a
requirement to use them. The problem of storing register values is that
binding is tied/coupled with hardware programming model, so you cannot
add a new device if the register value is a bit different (e.g.
LP55XX_CP_OFF is 0x1). You need entire new binding for such case. With
string - no need. With binding constants (IDs) also no need, so was this
the intention? Just to be clear - it is then ID or binding constant, not
a value for hardware register.

Best regards,
Krzysztof


2023-02-02 14:12:40

by Maarten Zanders

[permalink] [raw]
Subject: Re: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode


On 2/2/23 14:43, Krzysztof Kozlowski wrote:
>
> Strings in DTS are usually easier to for humans to read, but it's not a
> requirement to use them. The problem of storing register values is that
> binding is tied/coupled with hardware programming model, so you cannot
> add a new device if the register value is a bit different (e.g.
> LP55XX_CP_OFF is 0x1). You need entire new binding for such case. With
> string - no need.
I understand and this is why I started with the string in the first
place (as suggested by yourself in V1).
> With binding constants (IDs) also no need, so was this
> the intention? Just to be clear - it is then ID or binding constant, not
> a value for hardware register.
>
For simplicity sake, yes, now the setting is propagating directly into
the register as a bit value. But this is how the current implementation
of the drivers work. If we add a device in the future which indeed has
different bit mappings, that driver will have to do a mapping of the DT
binding to its own bit field definitions. I consider this DT binding as
the "master", which is now conveniently chosen to match the register values.

Cheers,

Maarten

2023-02-02 20:11:32

by Krzysztof Kozlowski

[permalink] [raw]
Subject: Re: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode

On 02/02/2023 15:12, Maarten Zanders wrote:
>
> On 2/2/23 14:43, Krzysztof Kozlowski wrote:
>>
>> Strings in DTS are usually easier to for humans to read, but it's not a
>> requirement to use them. The problem of storing register values is that
>> binding is tied/coupled with hardware programming model, so you cannot
>> add a new device if the register value is a bit different (e.g.
>> LP55XX_CP_OFF is 0x1). You need entire new binding for such case. With
>> string - no need.
> I understand and this is why I started with the string in the first
> place (as suggested by yourself in V1).
>> With binding constants (IDs) also no need, so was this
>> the intention? Just to be clear - it is then ID or binding constant, not
>> a value for hardware register.
>>
> For simplicity sake, yes, now the setting is propagating directly into
> the register as a bit value. But this is how the current implementation
> of the drivers work. If we add a device in the future which indeed has
> different bit mappings, that driver will have to do a mapping of the DT
> binding to its own bit field definitions. I consider this DT binding as
> the "master", which is now conveniently chosen to match the register values.

OK, that makes sense.

Best regards,
Krzysztof


2023-02-02 20:13:29

by Krzysztof Kozlowski

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Subject: Re: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode

On 02/02/2023 11:10, Maarten Zanders wrote:
> Add a binding to configure the internal charge pump for lp55xx.
>
> Signed-off-by: Maarten Zanders <[email protected]>
> ---
>
> Notes:
> v1: implement as bool to disable charge pump
> v2: rewrite to use string configuration, supporting all modes
> v3: simplification by replacing string option by u8 constant,
> removing previous Reviewed-by tags as it's a complete
> rewrite of the patch.
> v4: added notes
>
> .../devicetree/bindings/leds/leds-lp55xx.yaml | 8 ++++++++
> include/dt-bindings/leds/leds-lp55xx.h | 10 ++++++++++
> 2 files changed, 18 insertions(+)
> create mode 100644 include/dt-bindings/leds/leds-lp55xx.h
>
> diff --git a/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml b/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml
> index ae607911f1db..22e63d89d770 100644
> --- a/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml
> +++ b/Documentation/devicetree/bindings/leds/leds-lp55xx.yaml
> @@ -66,6 +66,12 @@ properties:
> '#size-cells':
> const: 0
>
> + ti,charge-pump-mode:
> + description:
> + Set the operating mode of the internal charge pump as defined in
> + <dt-bindings/leds/leds-lp55xx.h>. Defaults to auto.
> + $ref: /schemas/types.yaml#/definitions/uint8

This should be then uint32

default: 3
(and drop last sentence about default)

> +
> patternProperties:
> '^multi-led@[0-8]$':
> type: object
> @@ -152,6 +158,7 @@ additionalProperties: false
> examples:
> - |
> #include <dt-bindings/leds/common.h>
> + #include <dt-bindings/leds/leds-lp55xx.h>
>
> i2c {
> #address-cells = <1>;
> @@ -164,6 +171,7 @@ examples:
> reg = <0x32>;
> clock-mode = /bits/ 8 <2>;
> pwr-sel = /bits/ 8 <3>; /* D1~9 connected to VOUT */
> + ti,charge-pump-mode = /bits/ 8 <LP55XX_CP_BYPASS>;
>
> led@0 {
> reg = <0>;
> diff --git a/include/dt-bindings/leds/leds-lp55xx.h b/include/dt-bindings/leds/leds-lp55xx.h
> new file mode 100644
> index 000000000000..8f59c1c12dee
> --- /dev/null
> +++ b/include/dt-bindings/leds/leds-lp55xx.h
> @@ -0,0 +1,10 @@
> +/* SPDX-License-Identifier: GPL-2.0 */

Dual license.

> +#ifndef _DT_BINDINGS_LEDS_LP55XX_H
> +#define _DT_BINDINGS_LEDS_LP55XX_H
> +
> +#define LP55XX_CP_OFF 0
> +#define LP55XX_CP_BYPASS 1
> +#define LP55XX_CP_BOOST 2
> +#define LP55XX_CP_AUTO 3
> +
> +#endif /* _DT_BINDINGS_LEDS_LP55XX_H */

Best regards,
Krzysztof


2023-02-03 15:38:58

by Maarten Zanders

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Subject: Re: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode


On 2/2/23 21:13, Krzysztof Kozlowski wrote:
> + ti,charge-pump-mode:
>> + description:
>> + Set the operating mode of the internal charge pump as defined in
>> + <dt-bindings/leds/leds-lp55xx.h>. Defaults to auto.
>> + $ref: /schemas/types.yaml#/definitions/uint8
> This should be then uint32

Why is that? I specifically chose uint8 because other settings for LED
are also uint8. The implementation is also uint8. I surely hope we'll
never get to >256 modes for a charge pump.


> default: 3
> (and drop last sentence about default)
OK
> +/* SPDX-License-Identifier: GPL-2.0 */
> Dual license.

OK

Best regards,
Maarten


2023-02-03 17:54:15

by Krzysztof Kozlowski

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Subject: Re: [PATCH v4 1/2] dt-bindings: leds-lp55xx: add ti,charge-pump-mode

On 03/02/2023 16:38, Maarten Zanders wrote:
>
> On 2/2/23 21:13, Krzysztof Kozlowski wrote:
>> + ti,charge-pump-mode:
>>> + description:
>>> + Set the operating mode of the internal charge pump as defined in
>>> + <dt-bindings/leds/leds-lp55xx.h>. Defaults to auto.
>>> + $ref: /schemas/types.yaml#/definitions/uint8
>> This should be then uint32
>
> Why is that? I specifically chose uint8 because other settings for LED
> are also uint8. The implementation is also uint8. I surely hope we'll
> never get to >256 modes for a charge pump.

Because all IDs are unsigned int.

Best regards,
Krzysztof