Re: [PATCH v2 02/22] net: sunxi_emac: chase DT nodes to find PHY regulator

Hi Andre,

On 9/28/23 16:54, Andre Przywara wrote:

At the moment the sun4i EMAC driver relies on hardcoded CONFIG_MACPWR Kconfig symbols to enable potential PHY regulators. As we want to get rid of those, we need to find the regulator by chasing up the DT.

The sun4i-emac binding puts the PHY regulator into the MDIO node, which is the parent of the PHY device. U-Boot does not have (and does not need) an MDIO driver, so we need to chase down the regulator through the EMAC node: we follow the "phy-handle" property to find the PHY node, then go up to its parent, where we find the "phy-supply" link to the regulator. Let U-Boot find the associated regulator device, and put that into the private device struct, so we can find and enable the regulator at probe time, later.

This does somewhat duplicate the logic from dm_eth_connect_phy_handle(), and putting the regulator in a UCLASS_MDIO device's probe function would work out cleanly (albeit with the usual DM overhead). But that can be a later refactoring.

Signed-off-by: Andre Przywara andre.przywara@arm.com Reviewed-by: Sam Edwards CFSworks@gmail.com

---

drivers/net/sunxi_emac.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+)

diff --git a/drivers/net/sunxi_emac.c b/drivers/net/sunxi_emac.c index 4c90d4b4981..f1f0e5bbbb2 100644 --- a/drivers/net/sunxi_emac.c +++ b/drivers/net/sunxi_emac.c @@ -17,6 +17,7 @@ #include <net.h> #include <asm/io.h> #include <asm/arch/clock.h> +#include <power/regulator.h>

/* EMAC register */ struct emac_regs { @@ -165,6 +166,7 @@ struct emac_eth_dev { struct phy_device *phydev; int link_printed; uchar rx_buf[EMAC_RX_BUFSIZE];

• struct udevice *phy_reg;

};

struct emac_rxhdr { @@ -572,6 +574,9 @@ static int sunxi_emac_eth_probe(struct udevice *dev) if (ret) return ret;

• if (priv->phy_reg)

• regulator_set_enable(priv->phy_reg, true);
  

• return sunxi_emac_init_phy(priv, dev);

}

@@ -585,9 +590,43 @@ static const struct eth_ops sunxi_emac_eth_ops = { static int sunxi_emac_eth_of_to_plat(struct udevice *dev) { struct eth_pdata *pdata = dev_get_plat(dev);

• struct emac_eth_dev *priv = dev_get_priv(dev);

• struct ofnode_phandle_args args;

• ofnode mdio_node;

• int ret;

  pdata->iobase = dev_read_addr(dev);

• /* The PHY regulator is in the MDIO node, not the EMAC or PHY node. */

• ret = dev_read_phandle_with_args(dev, "phy-handle", NULL, 0, 0, &args);

You can use dev_get_phy_node() here. Either way:

Reviewed-by: Samuel Holland samuel@sholland.org

• if (ret) {

• dev_err(dev, "failed to get PHY node\n");
  

• return ret;
  

• }
• /*

• * U-Boot does not have (and does not need) a device driver for the
  

• * MDIO device, so just "pass through" that DT node to get to the
  

• * regulator phandle.
  

• * The PHY regulator is optional, though: ignore if we cannot find
  

• * a phy-supply property.
  

• */
  

• mdio_node = ofnode_get_parent(args.node);
• ret= ofnode_parse_phandle_with_args(mdio_node, "phy-supply", NULL, 0, 0,

• 			    &args);
  

• if (ret && ret != -ENOENT) {

• dev_err(dev, "failed to get PHY supply node\n");
  

• return ret;
  

• }
• if (!ret) {

• ret = uclass_get_device_by_ofnode(UCLASS_REGULATOR, args.node,
  

• 				  &priv->phy_reg);
  

• if (ret) {
  

• 	dev_err(dev, "failed to get PHY regulator node\n");
  

• 	return ret;
  

• }
  

• }
• return 0;

}