net: pcs: rzn1-miic: move port range handling into SoC data

Define per-SoC miic_port_start and miic_port_max fields in struct
miic_of_data and use them to validate the device-tree "reg" port number
and to compute the driver's internal zero-based port index as
(port - miic_port_start). Replace uses of the hard-coded MIIC_MAX_NR_PORTS
with the SoC-provided miic_port_max when iterating over ports.

On RZ/N1 the MIIC ports are numbered 1..5, whereas RZ/T2H numbers its MIIC
ports 0..3. By making the port base and range part of the OF data the
driver no longer assumes a fixed numbering scheme and can support SoCs that
enumerate ports from either zero or one and that expose different numbers
of ports.

This change is preparatory work for adding RZ/T2H support.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://patch.msgid.link/20250910204132.319975-6-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/pcs/pcs-rzn1-miic.c b/drivers/net/pcs/pcs-rzn1-miic.c
index afa0c2ffbd30c2bdc079ff7de6bc23cd95491f88..31d9e0982ad65c765a732aa5c0101e73da0f0577 100644 (file)
--- a/drivers/net/pcs/pcs-rzn1-miic.c
+++ b/drivers/net/pcs/pcs-rzn1-miic.c
@@ -49,8 +49,6 @@
 #define MIIC_SWCTRL                    0x304
 #define MIIC_SWDUPC                    0x308
 
-#define MIIC_MAX_NR_PORTS              5
-
 #define MIIC_MODCTRL_CONF_CONV_MAX     6
 #define MIIC_MODCTRL_CONF_NONE         -1
 
@@ -146,6 +144,8 @@ struct miic {
  * @conf_to_string_count: Number of entries in the conf_to_string array
  * @index_to_string: String representations of the index values
  * @index_to_string_count: Number of entries in the index_to_string array
+ * @miic_port_start: MIIC port start number
+ * @miic_port_max: Maximum MIIC supported
  */
 struct miic_of_data {
        struct modctrl_match *match_table;
@@ -155,6 +155,8 @@ struct miic_of_data {
        u8 conf_to_string_count;
        const char * const *index_to_string;
        u8 index_to_string_count;
+       u8 miic_port_start;
+       u8 miic_port_max;
 };
 
 /**
@@ -330,6 +332,7 @@ static const struct phylink_pcs_ops miic_phylink_ops = {
 
 struct phylink_pcs *miic_create(struct device *dev, struct device_node *np)
 {
+       const struct miic_of_data *of_data;
        struct platform_device *pdev;
        struct miic_port *miic_port;
        struct device_node *pcs_np;
@@ -342,9 +345,6 @@ struct phylink_pcs *miic_create(struct device *dev, struct device_node *np)
        if (of_property_read_u32(np, "reg", &port))
                return ERR_PTR(-EINVAL);
 
-       if (port > MIIC_MAX_NR_PORTS || port < 1)
-               return ERR_PTR(-EINVAL);
-
        /* The PCS pdev is attached to the parent node */
        pcs_np = of_get_parent(np);
        if (!pcs_np)
@@ -363,18 +363,24 @@ struct phylink_pcs *miic_create(struct device *dev, struct device_node *np)
                return ERR_PTR(-EPROBE_DEFER);
        }
 
+       miic = platform_get_drvdata(pdev);
+       of_data = miic->of_data;
+       if (port > of_data->miic_port_max || port < of_data->miic_port_start) {
+               put_device(&pdev->dev);
+               return ERR_PTR(-EINVAL);
+       }
+
        miic_port = kzalloc(sizeof(*miic_port), GFP_KERNEL);
        if (!miic_port) {
                put_device(&pdev->dev);
                return ERR_PTR(-ENOMEM);
        }
 
-       miic = platform_get_drvdata(pdev);
        device_link_add(dev, miic->dev, DL_FLAG_AUTOREMOVE_CONSUMER);
        put_device(&pdev->dev);
 
        miic_port->miic = miic;
-       miic_port->port = port - 1;
+       miic_port->port = port - of_data->miic_port_start;
        miic_port->pcs.ops = &miic_phylink_ops;
 
        phy_interface_set_rgmii(miic_port->pcs.supported_interfaces);
@@ -410,7 +416,7 @@ static int miic_init_hw(struct miic *miic, u32 cfg_mode)
        miic_reg_writel(miic, MIIC_MODCTRL,
                        FIELD_PREP(MIIC_MODCTRL_SW_MODE, cfg_mode));
 
-       for (port = 0; port < MIIC_MAX_NR_PORTS; port++) {
+       for (port = 0; port < miic->of_data->miic_port_max; port++) {
                miic_converter_enable(miic, port, 0);
                /* Disable speed/duplex control from these registers, datasheet
                 * says switch registers should be used to setup switch port
@@ -499,6 +505,8 @@ static int miic_parse_dt(struct miic *miic, u32 *mode_cfg)
                if (of_property_read_u32(conv, "reg", &port))
                        continue;
 
+               /* Adjust for 0 based index */
+               port += !miic->of_data->miic_port_start;
                if (of_property_read_u32(conv, "renesas,miic-input", &conf) == 0)
                        dt_val[port] = conf;
        }
@@ -572,6 +580,8 @@ static struct miic_of_data rzn1_miic_of_data = {
        .conf_to_string_count = ARRAY_SIZE(conf_to_string),
        .index_to_string = index_to_string,
        .index_to_string_count = ARRAY_SIZE(index_to_string),
+       .miic_port_start = 1,
+       .miic_port_max = 5,
 };
 
 static const struct of_device_id miic_of_mtable[] = {