Commit ba5560e5 authored by Lucien.Jheng's avatar Lucien.Jheng Committed by Jakub Kicinski
Browse files

net: phy: air_en8811h: Add clk provider for CKO pin 



EN8811H outputs 25MHz or 50MHz clocks on CKO, selected by GPIO3.
CKO clock operates continuously from power-up through md32 loading.
Implement clk provider driver so we can disable the clock output in case
it isn't needed, which also helps to reduce EMF noise

Signed-off-by: default avatarLucien.Jheng <lucienx123@gmail.com>
Reviewed-by: default avatarAndrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20250409150902.3596-1-lucienx123@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent faeefc17

drivers/net/phy/air_en8811h.c

+100 −3
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
 * Copyright (C) 2023 Airoha Technology Corp.

 */



#include <linux/clk-provider.h>

#include <linux/phy.h>

#include <linux/firmware.h>

#include <linux/property.h>
@@ -115,6 +116,11 @@ 
#define EN8811H_GPIO_OUTPUT		0xcf8b8

#define   EN8811H_GPIO_OUTPUT_345		(BIT(3) | BIT(4) | BIT(5))



#define EN8811H_HWTRAP1			0xcf914

#define   EN8811H_HWTRAP1_CKO			BIT(12)

#define EN8811H_CLK_CGM			0xcf958

#define   EN8811H_CLK_CGM_CKO			BIT(26)



#define EN8811H_FW_CTRL_1		0x0f0018

#define   EN8811H_FW_CTRL_1_START		0x0

#define   EN8811H_FW_CTRL_1_FINISH		0x1
@@ -142,10 +148,15 @@ struct led { 
	unsigned long state;

};



#define clk_hw_to_en8811h_priv(_hw)			\

	container_of(_hw, struct en8811h_priv, hw)



struct en8811h_priv {

	u32			firmware_version;

	bool			mcu_needs_restart;

	struct led		led[EN8811H_LED_COUNT];

	struct clk_hw		hw;

	struct phy_device	*phydev;

};



enum {
@@ -806,6 +817,86 @@ static int en8811h_led_hw_is_supported(struct phy_device *phydev, u8 index, 
	return 0;

};



static unsigned long en8811h_clk_recalc_rate(struct clk_hw *hw,

					     unsigned long parent)

{

	struct en8811h_priv *priv = clk_hw_to_en8811h_priv(hw);

	struct phy_device *phydev = priv->phydev;

	u32 pbus_value;

	int ret;



	ret = air_buckpbus_reg_read(phydev, EN8811H_HWTRAP1, &pbus_value);

	if (ret < 0)

		return ret;



	return (pbus_value & EN8811H_HWTRAP1_CKO) ? 50000000 : 25000000;

}



static int en8811h_clk_enable(struct clk_hw *hw)

{

	struct en8811h_priv *priv = clk_hw_to_en8811h_priv(hw);

	struct phy_device *phydev = priv->phydev;



	return air_buckpbus_reg_modify(phydev, EN8811H_CLK_CGM,

				       EN8811H_CLK_CGM_CKO,

				       EN8811H_CLK_CGM_CKO);

}



static void en8811h_clk_disable(struct clk_hw *hw)

{

	struct en8811h_priv *priv = clk_hw_to_en8811h_priv(hw);

	struct phy_device *phydev = priv->phydev;



	air_buckpbus_reg_modify(phydev, EN8811H_CLK_CGM,

				EN8811H_CLK_CGM_CKO, 0);

}



static int en8811h_clk_is_enabled(struct clk_hw *hw)

{

	struct en8811h_priv *priv = clk_hw_to_en8811h_priv(hw);

	struct phy_device *phydev = priv->phydev;

	u32 pbus_value;

	int ret;



	ret = air_buckpbus_reg_read(phydev, EN8811H_CLK_CGM, &pbus_value);

	if (ret < 0)

		return ret;



	return (pbus_value & EN8811H_CLK_CGM_CKO);

}



static const struct clk_ops en8811h_clk_ops = {

	.recalc_rate	= en8811h_clk_recalc_rate,

	.enable		= en8811h_clk_enable,

	.disable	= en8811h_clk_disable,

	.is_enabled	= en8811h_clk_is_enabled,

};



static int en8811h_clk_provider_setup(struct device *dev, struct clk_hw *hw)

{

	struct clk_init_data init;

	int ret;



	if (!IS_ENABLED(CONFIG_COMMON_CLK))

		return 0;



	init.name = devm_kasprintf(dev, GFP_KERNEL, "%s-cko",

				   fwnode_get_name(dev_fwnode(dev)));

	if (!init.name)

		return -ENOMEM;



	init.ops = &en8811h_clk_ops;

	init.flags = 0;

	init.num_parents = 0;

	hw->init = &init;



	ret = devm_clk_hw_register(dev, hw);

	if (ret)

		return ret;



	return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, hw);

}



static int en8811h_probe(struct phy_device *phydev)

{

	struct en8811h_priv *priv;
@@ -838,6 +929,12 @@ static int en8811h_probe(struct phy_device *phydev) 
		return ret;

	}



	priv->phydev = phydev;

	/* Co-Clock Output */

	ret = en8811h_clk_provider_setup(&phydev->mdio.dev, &priv->hw);

	if (ret)

		return ret;



	/* Configure led gpio pins as output */

	ret = air_buckpbus_reg_modify(phydev, EN8811H_GPIO_OUTPUT,

				      EN8811H_GPIO_OUTPUT_345,