diff options
Diffstat (limited to 'drivers/net/phy/ncn26000.c')
| -rw-r--r-- | drivers/net/phy/ncn26000.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/drivers/net/phy/ncn26000.c b/drivers/net/phy/ncn26000.c new file mode 100644 index 000000000000..5680584f659e --- /dev/null +++ b/drivers/net/phy/ncn26000.c @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause) +/* + * Driver for the onsemi 10BASE-T1S NCN26000 PHYs family. + * + * Copyright 2022 onsemi + */ +#include <linux/kernel.h> +#include <linux/bitfield.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/mii.h> +#include <linux/phy.h> + +#include "mdio-open-alliance.h" + +#define PHY_ID_NCN26000 0x180FF5A1 + +#define NCN26000_REG_IRQ_CTL 16 +#define NCN26000_REG_IRQ_STATUS 17 + +// the NCN26000 maps link_ctrl to BMCR_ANENABLE +#define NCN26000_BCMR_LINK_CTRL_BIT BMCR_ANENABLE + +// the NCN26000 maps link_status to BMSR_ANEGCOMPLETE +#define NCN26000_BMSR_LINK_STATUS_BIT BMSR_ANEGCOMPLETE + +#define NCN26000_IRQ_LINKST_BIT BIT(0) +#define NCN26000_IRQ_PLCAST_BIT BIT(1) +#define NCN26000_IRQ_LJABBER_BIT BIT(2) +#define NCN26000_IRQ_RJABBER_BIT BIT(3) +#define NCN26000_IRQ_PLCAREC_BIT BIT(4) +#define NCN26000_IRQ_PHYSCOL_BIT BIT(5) +#define NCN26000_IRQ_RESET_BIT BIT(15) + +#define TO_TMR_DEFAULT 32 + +static int ncn26000_config_init(struct phy_device *phydev) +{ + /* HW bug workaround: the default value of the PLCA TO_TIMER should be + * 32, where the current version of NCN26000 reports 24. This will be + * fixed in future PHY versions. For the time being, we force the + * correct default here. + */ + return phy_write_mmd(phydev, MDIO_MMD_VEND2, MDIO_OATC14_PLCA_TOTMR, + TO_TMR_DEFAULT); +} + +static int ncn26000_config_aneg(struct phy_device *phydev) +{ + /* Note: the NCN26000 supports only P2MP link mode. Therefore, AN is not + * supported. However, this function is invoked by phylib to enable the + * PHY, regardless of the AN support. + */ + phydev->mdix_ctrl = ETH_TP_MDI_AUTO; + phydev->mdix = ETH_TP_MDI; + + // bring up the link + return phy_write(phydev, MII_BMCR, NCN26000_BCMR_LINK_CTRL_BIT); +} + +static int ncn26000_read_status(struct phy_device *phydev) +{ + /* The NCN26000 reports NCN26000_LINK_STATUS_BIT if the link status of + * the PHY is up. It further reports the logical AND of the link status + * and the PLCA status in the BMSR_LSTATUS bit. + */ + int ret; + + /* The link state is latched low so that momentary link + * drops can be detected. Do not double-read the status + * in polling mode to detect such short link drops except + * the link was already down. + */ + if (!phy_polling_mode(phydev) || !phydev->link) { + ret = phy_read(phydev, MII_BMSR); + if (ret < 0) + return ret; + else if (ret & NCN26000_BMSR_LINK_STATUS_BIT) + goto upd_link; + } + + ret = phy_read(phydev, MII_BMSR); + if (ret < 0) + return ret; + +upd_link: + // update link status + if (ret & NCN26000_BMSR_LINK_STATUS_BIT) { + phydev->link = 1; + phydev->pause = 0; + phydev->duplex = DUPLEX_HALF; + phydev->speed = SPEED_10; + } else { + phydev->link = 0; + phydev->duplex = DUPLEX_UNKNOWN; + phydev->speed = SPEED_UNKNOWN; + } + + return 0; +} + +static irqreturn_t ncn26000_handle_interrupt(struct phy_device *phydev) +{ + int ret; + + // read and aknowledge the IRQ status register + ret = phy_read(phydev, NCN26000_REG_IRQ_STATUS); + + // check only link status changes + if (ret < 0 || (ret & NCN26000_REG_IRQ_STATUS) == 0) + return IRQ_NONE; + + phy_trigger_machine(phydev); + return IRQ_HANDLED; +} + +static int ncn26000_config_intr(struct phy_device *phydev) +{ + int ret; + u16 irqe; + + if (phydev->interrupts == PHY_INTERRUPT_ENABLED) { + // acknowledge IRQs + ret = phy_read(phydev, NCN26000_REG_IRQ_STATUS); + if (ret < 0) + return ret; + + // get link status notifications + irqe = NCN26000_IRQ_LINKST_BIT; + } else { + // disable all IRQs + irqe = 0; + } + + ret = phy_write(phydev, NCN26000_REG_IRQ_CTL, irqe); + if (ret != 0) + return ret; + + return 0; +} + +static struct phy_driver ncn26000_driver[] = { + { + PHY_ID_MATCH_MODEL(PHY_ID_NCN26000), + .name = "NCN26000", + .features = PHY_BASIC_T1S_P2MP_FEATURES, + .config_init = ncn26000_config_init, + .config_intr = ncn26000_config_intr, + .config_aneg = ncn26000_config_aneg, + .read_status = ncn26000_read_status, + .handle_interrupt = ncn26000_handle_interrupt, + .get_plca_cfg = genphy_c45_plca_get_cfg, + .set_plca_cfg = genphy_c45_plca_set_cfg, + .get_plca_status = genphy_c45_plca_get_status, + .soft_reset = genphy_soft_reset, + }, +}; + +module_phy_driver(ncn26000_driver); + +static struct mdio_device_id __maybe_unused ncn26000_tbl[] = { + { PHY_ID_MATCH_MODEL(PHY_ID_NCN26000) }, + { } +}; + +MODULE_DEVICE_TABLE(mdio, ncn26000_tbl); + +MODULE_AUTHOR("Piergiorgio Beruto"); +MODULE_DESCRIPTION("onsemi 10BASE-T1S PHY driver"); +MODULE_LICENSE("Dual BSD/GPL"); |