Commit d4beef41 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'dsa-realtek-reset' 



Luiz Angelo Daros de Luca says:

====================
net: dsa: realtek: support reset controller and update docs

The driver previously supported reset pins using GPIO, but it lacked
support for reset controllers. Although a reset method is generally not
required, the driver fails to detect the switch if the reset was kept
asserted by a previous driver.

This series adds support to reset a Realtek switch using a reset
controller. It also updates the binding documentation to remove the
requirement of a reset method and to add the new reset controller
property.

It was tested on a TL-WR1043ND v1 router (rtl8366rb via SMI).

Signed-off-by: default avatarLuiz Angelo Daros de Luca <luizluca@gmail.com>
---
Changes in v5:
- Fixed error checking logic when reset controller (de)assert fails
- Link to v4: https://lore.kernel.org/r/20240219-realtek-reset-v4-0-858b82a29503@gmail.com

Changes in v4:
- do not test for priv->reset,priv->reset_ctl
- updated commit message
- Link to v3: https://lore.kernel.org/r/20240213-realtek-reset-v3-0-37837e574713@gmail.com

Changes in v3:
- Rebased on the Realtek DSA driver refactoring (08f62716)
- Dropped the reset controller example in bindings
- Used %pe in error printing
- Linked to v2: https://lore.kernel.org/r/20231027190910.27044-1-luizluca@gmail.com/

Changes in v2:
- Introduced a dedicated commit for removing the reset-gpios requirement
- Placed binding patches before code changes
- Removed the 'reset-names' property
- Moved the example from the commit message to realtek.yaml
- Split the reset function into _assert/_deassert variants
- Modified reset functions to return a warning instead of a value
- Utilized devm_reset_control_get_optional to prevent failure when the
  reset control is missing
- Used 'true' and 'false' for boolean values
- Removed the CONFIG_RESET_CONTROLLER check as stub methods are
  sufficient when undefined
- Linked to v1: https://lore.kernel.org/r/20231024205805.19314-1-luizluca@gmail.com/


====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 4440873f 56998aa6

Documentation/devicetree/bindings/net/dsa/realtek.yaml

+3 −1
Original line number Diff line number Diff line
@@ -59,6 +59,9 @@ properties: 
    description: GPIO to be used to reset the whole device

    maxItems: 1



  resets:

    maxItems: 1



  realtek,disable-leds:

    type: boolean

    description: |
@@ -127,7 +130,6 @@ else: 
    - mdc-gpios

    - mdio-gpios

    - mdio

    - reset-gpios



required:

  - compatible

drivers/net/dsa/realtek/realtek.h

+2 −0
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include <linux/platform_device.h>

#include <linux/gpio/consumer.h>

#include <net/dsa.h>

#include <linux/reset.h>



#define REALTEK_HW_STOP_DELAY		25	/* msecs */

#define REALTEK_HW_START_DELAY		100	/* msecs */
@@ -48,6 +49,7 @@ struct rtl8366_vlan_4k { 


struct realtek_priv {

	struct device		*dev;

	struct reset_control    *reset_ctl;

	struct gpio_desc	*reset;

	struct gpio_desc	*mdc;

	struct gpio_desc	*mdio;

drivers/net/dsa/realtek/rtl83xx.c

+37 −5
Original line number Diff line number Diff line
@@ -184,6 +184,13 @@ rtl83xx_probe(struct device *dev, 
						    "realtek,disable-leds");



	/* TODO: if power is software controlled, set up any regulators here */

	priv->reset_ctl = devm_reset_control_get_optional(dev, NULL);

	if (IS_ERR(priv->reset_ctl)) {

		ret = PTR_ERR(priv->reset_ctl);

		dev_err_probe(dev, ret, "failed to get reset control\n");

		return ERR_CAST(priv->reset_ctl);

	}



	priv->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);

	if (IS_ERR(priv->reset)) {

		dev_err(dev, "failed to get RESET GPIO\n");
@@ -192,11 +199,11 @@ rtl83xx_probe(struct device *dev, 


	dev_set_drvdata(dev, priv);



	if (priv->reset) {

		gpiod_set_value(priv->reset, 1);

	if (priv->reset_ctl || priv->reset) {

		rtl83xx_reset_assert(priv);

		dev_dbg(dev, "asserted RESET\n");

		msleep(REALTEK_HW_STOP_DELAY);

		gpiod_set_value(priv->reset, 0);

		rtl83xx_reset_deassert(priv);

		msleep(REALTEK_HW_START_DELAY);

		dev_dbg(dev, "deasserted RESET\n");

	}
@@ -292,11 +299,36 @@ EXPORT_SYMBOL_NS_GPL(rtl83xx_shutdown, REALTEK_DSA); 
void rtl83xx_remove(struct realtek_priv *priv)

{

	/* leave the device reset asserted */

	if (priv->reset)

		gpiod_set_value(priv->reset, 1);

	rtl83xx_reset_assert(priv);

}

EXPORT_SYMBOL_NS_GPL(rtl83xx_remove, REALTEK_DSA);



void rtl83xx_reset_assert(struct realtek_priv *priv)

{

	int ret;



	ret = reset_control_assert(priv->reset_ctl);

	if (ret)

		dev_warn(priv->dev,

			 "Failed to assert the switch reset control: %pe\n",

			 ERR_PTR(ret));



	gpiod_set_value(priv->reset, true);

}



void rtl83xx_reset_deassert(struct realtek_priv *priv)

{

	int ret;



	ret = reset_control_deassert(priv->reset_ctl);

	if (ret)

		dev_warn(priv->dev,

			 "Failed to deassert the switch reset control: %pe\n",

			 ERR_PTR(ret));



	gpiod_set_value(priv->reset, false);

}



MODULE_AUTHOR("Luiz Angelo Daros de Luca <luizluca@gmail.com>");

MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");

MODULE_DESCRIPTION("Realtek DSA switches common module");

drivers/net/dsa/realtek/rtl83xx.h

+2 −0
Original line number Diff line number Diff line
@@ -18,5 +18,7 @@ int rtl83xx_register_switch(struct realtek_priv *priv); 
void rtl83xx_unregister_switch(struct realtek_priv *priv);

void rtl83xx_shutdown(struct realtek_priv *priv);

void rtl83xx_remove(struct realtek_priv *priv);

void rtl83xx_reset_assert(struct realtek_priv *priv);

void rtl83xx_reset_deassert(struct realtek_priv *priv);



#endif /* _RTL83XX_H */