Re: [PATCH net-next v3 2/4] net: ethernet: altera-tse: Convert to mdio-regmap and use PCS Lynx
From: Simon Horman <hidden>
Date: 2023-05-26 08:39:27
Also in:
linux-arm-kernel, lkml
On Fri, May 26, 2023 at 09:42:50AM +0200, Maxime Chevallier wrote:
The newly introduced regmap-based MDIO driver allows for an easy mapping of an mdiodevice onto the memory-mapped TSE PCS, which is actually a Lynx PCS. Convert Altera TSE to use this PCS instead of the pcs-altera-tse, which is nothing more than a memory-mapped Lynx PCS. Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Hi Maxime, I have some concerns about the error paths in this patch. ...
quoted hunk ↗ jump to hunk
@@ -1134,13 +1136,21 @@ static int altera_tse_probe(struct platform_device *pdev) const struct of_device_id *of_id = NULL; struct altera_tse_private *priv; struct resource *control_port; + struct regmap *pcs_regmap; struct resource *dma_res; struct resource *pcs_res; + struct mii_bus *pcs_bus; struct net_device *ndev; void __iomem *descmap; - int pcs_reg_width = 2; int ret = -ENODEV; + struct regmap_config pcs_regmap_cfg;
nit: this probably belongs in with the bunch of declarations above it.
+
+ struct mdio_regmap_config mrc = {
+ .parent = &pdev->dev,
+ .valid_addr = 0x0,
+ };nit: maybe this too.
quoted hunk ↗ jump to hunk
+ ndev = alloc_etherdev(sizeof(struct altera_tse_private)); if (!ndev) { dev_err(&pdev->dev, "Could not allocate network device\n");@@ -1258,10 +1268,29 @@ static int altera_tse_probe(struct platform_device *pdev) ret = request_and_map(pdev, "pcs", &pcs_res, &priv->pcs_base); if (ret) { + /* If we can't find a dedicated resource for the PCS, fallback + * to the internal PCS, that has a different address stride + */ priv->pcs_base = priv->mac_dev + tse_csroffs(mdio_phy0); - pcs_reg_width = 4; + pcs_regmap_cfg.reg_bits = 32; + /* Values are MDIO-like values, on 16 bits */ + pcs_regmap_cfg.val_bits = 16; + pcs_regmap_cfg.reg_shift = REGMAP_UPSHIFT(2); + } else { + pcs_regmap_cfg.reg_bits = 16; + pcs_regmap_cfg.val_bits = 16; + pcs_regmap_cfg.reg_shift = REGMAP_UPSHIFT(1); } + /* Create a regmap for the PCS so that it can be used by the PCS driver */ + pcs_regmap = devm_regmap_init_mmio(&pdev->dev, priv->pcs_base, + &pcs_regmap_cfg); + if (IS_ERR(pcs_regmap)) { + ret = PTR_ERR(pcs_regmap); + goto err_free_netdev; + } + mrc.regmap = pcs_regmap; + /* Rx IRQ */ priv->rx_irq = platform_get_irq_byname(pdev, "rx_irq"); if (priv->rx_irq == -ENXIO) {@@ -1384,7 +1413,20 @@ static int altera_tse_probe(struct platform_device *pdev) (unsigned long) control_port->start, priv->rx_irq, priv->tx_irq); - priv->pcs = alt_tse_pcs_create(ndev, priv->pcs_base, pcs_reg_width); + snprintf(mrc.name, MII_BUS_ID_SIZE, "%s-pcs-mii", ndev->name); + pcs_bus = devm_mdio_regmap_register(&pdev->dev, &mrc); + if (IS_ERR(pcs_bus)) { + ret = PTR_ERR(pcs_bus); + goto err_init_phy; + } + + priv->pcs_mdiodev = mdio_device_create(pcs_bus, 0);
mdio_device_create() can fail. Should that be handled here?
+
+ priv->pcs = lynx_pcs_create(priv->pcs_mdiodev);
+ if (!priv->pcs) {
+ ret = -ENODEV;
+ goto err_init_phy;Does this leak priv->pcs_mdiodev?
quoted hunk ↗ jump to hunk
+ } priv->phylink_config.dev = &ndev->dev; priv->phylink_config.type = PHYLINK_NETDEV;@@ -1407,11 +1449,12 @@ static int altera_tse_probe(struct platform_device *pdev) if (IS_ERR(priv->phylink)) { dev_err(&pdev->dev, "failed to create phylink\n"); ret = PTR_ERR(priv->phylink); - goto err_init_phy; + goto err_pcs;
Does this leak priv->pcs ?
quoted hunk ↗ jump to hunk
} return 0; - +err_pcs: + mdio_device_free(priv->pcs_mdiodev); err_init_phy: unregister_netdev(ndev); err_register_netdev:@@ -1433,6 +1476,8 @@ static int altera_tse_remove(struct platform_device *pdev) altera_tse_mdio_destroy(ndev); unregister_netdev(ndev); phylink_destroy(priv->phylink); + mdio_device_free(priv->pcs_mdiodev); + free_netdev(ndev); return 0;diff --git a/include/linux/mdio/mdio-regmap.h b/include/linux/mdio/mdio-regmap.h index b8508f152552..679d9069846b 100644 --- a/include/linux/mdio/mdio-regmap.h +++ b/include/linux/mdio/mdio-regmap.h@@ -7,6 +7,8 @@ #ifndef MDIO_REGMAP_H #define MDIO_REGMAP_H +#include <linux/phy.h> + struct device; struct regmap;
This hunk doesn't seem strictly related to the patch. Perhaps the include belongs elsewhere. Or the hunk belongs in another patch.