| // SPDX-License-Identifier: GPL-2.0 |
| /* Driver for the Texas Instruments DP83TG720 PHY |
| * Copyright (c) 2023 Pengutronix, Oleksij Rempel <kernel@pengutronix.de> |
| */ |
| #include <linux/bitfield.h> |
| #include <linux/ethtool_netlink.h> |
| #include <linux/jiffies.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/phy.h> |
| #include <linux/random.h> |
| |
| #include "open_alliance_helpers.h" |
| |
| /* |
| * DP83TG720 PHY Limitations and Workarounds |
| * |
| * The DP83TG720 1000BASE-T1 PHY has several limitations that require |
| * software-side mitigations. These workarounds are implemented throughout |
| * this driver. This section documents the known issues and their corresponding |
| * mitigation strategies. |
| * |
| * 1. Unreliable Link Detection and Synchronized Reset Deadlock |
| * ------------------------------------------------------------ |
| * After a link loss or during link establishment, the DP83TG720 PHY may fail |
| * to detect or report link status correctly. As of June 2025, no public |
| * errata sheet for the DP83TG720 PHY documents this behavior. |
| * The "DP83TC81x, DP83TG72x Software Implementation Guide" application note |
| * (SNLA404, available at https://www.ti.com/lit/an/snla404/snla404.pdf) |
| * recommends performing a soft restart if polling for a link fails to establish |
| * a connection after 100ms. This procedure is adopted as the workaround for the |
| * observed link detection issue. |
| * |
| * However, in point-to-point setups where both link partners use the same |
| * driver (e.g. Linux on both sides), a synchronized reset pattern may emerge. |
| * This leads to a deadlock, where both PHYs reset at the same time and |
| * continuously miss each other during auto-negotiation. |
| * |
| * To address this, the reset procedure includes two components: |
| * |
| * - A **fixed minimum delay of 1ms** after a hardware reset. The datasheet |
| * "DP83TG720S-Q1 1000BASE-T1 Automotive Ethernet PHY with SGMII and RGMII" |
| * specifies this as the "Post reset stabilization-time prior to MDC preamble |
| * for register access" (T6.2), ensuring the PHY is ready for MDIO |
| * operations. |
| * |
| * - An **additional asymmetric delay**, empirically chosen based on |
| * master/slave role. This reduces the risk of synchronized resets on both |
| * link partners. Values are selected to avoid periodic overlap and ensure |
| * the link is re-established within a few cycles. |
| * |
| * The functions that implement this logic are: |
| * - dp83tg720_soft_reset() |
| * - dp83tg720_get_next_update_time() |
| * |
| * 2. Polling-Based Link Detection and IRQ Support |
| * ----------------------------------------------- |
| * Due to the PHY-specific limitation described in section 1, link-up events |
| * cannot be reliably detected via interrupts on the DP83TG720. Therefore, |
| * polling is required to detect transitions from link-down to link-up. |
| * |
| * While link-down events *can* be detected via IRQs on this PHY, this driver |
| * currently does **not** implement interrupt support. As a result, all link |
| * state changes must be detected using polling. |
| * |
| * Polling behavior: |
| * - When the link is up: slow polling (e.g. 1s). |
| * - When the link just went down: fast polling for a short time. |
| * - When the link stays down: fallback to slow polling. |
| * |
| * This design balances responsiveness and CPU usage. It sacrifices fast link-up |
| * times in cases where the link is expected to remain down for extended periods, |
| * assuming that such systems do not require immediate reactivity. |
| */ |
| |
| /* |
| * DP83TG720S_POLL_ACTIVE_LINK - Polling interval in milliseconds when the link |
| * is active. |
| * DP83TG720S_POLL_NO_LINK - Polling interval in milliseconds when the |
| * link is down. |
| * DP83TG720S_FAST_POLL_DURATION_MS - Timeout in milliseconds for no-link |
| * polling after which polling interval is |
| * increased. |
| * DP83TG720S_POLL_SLOW - Slow polling interval when there is no |
| * link for a prolongued period. |
| * DP83TG720S_RESET_DELAY_MS_MASTER - Delay after a reset before attempting |
| * to establish a link again for master phy. |
| * DP83TG720S_RESET_DELAY_MS_SLAVE - Delay after a reset before attempting |
| * to establish a link again for slave phy. |
| * |
| * These values are not documented or officially recommended by the vendor but |
| * were determined through empirical testing. They achieve a good balance in |
| * minimizing the number of reset retries while ensuring reliable link recovery |
| * within a reasonable timeframe. |
| */ |
| #define DP83TG720S_POLL_ACTIVE_LINK 421 |
| #define DP83TG720S_POLL_NO_LINK 149 |
| #define DP83TG720S_FAST_POLL_DURATION_MS 6000 |
| #define DP83TG720S_POLL_SLOW 1117 |
| #define DP83TG720S_RESET_DELAY_MS_MASTER 97 |
| #define DP83TG720S_RESET_DELAY_MS_SLAVE 149 |
| |
| #define DP83TG720S_PHY_ID 0x2000a284 |
| |
| /* MDIO_MMD_VEND2 registers */ |
| #define DP83TG720S_MII_REG_10 0x10 |
| #define DP83TG720S_STS_MII_INT BIT(7) |
| #define DP83TG720S_LINK_STATUS BIT(0) |
| |
| /* TDR Configuration Register (0x1E) */ |
| #define DP83TG720S_TDR_CFG 0x1e |
| /* 1b = TDR start, 0b = No TDR */ |
| #define DP83TG720S_TDR_START BIT(15) |
| /* 1b = TDR auto on link down, 0b = Manual TDR start */ |
| #define DP83TG720S_CFG_TDR_AUTO_RUN BIT(14) |
| /* 1b = TDR done, 0b = TDR in progress */ |
| #define DP83TG720S_TDR_DONE BIT(1) |
| /* 1b = TDR fail, 0b = TDR success */ |
| #define DP83TG720S_TDR_FAIL BIT(0) |
| |
| #define DP83TG720S_PHY_RESET 0x1f |
| #define DP83TG720S_HW_RESET BIT(15) |
| |
| #define DP83TG720S_LPS_CFG3 0x18c |
| /* Power modes are documented as bit fields but used as values */ |
| /* Power Mode 0 is Normal mode */ |
| #define DP83TG720S_LPS_CFG3_PWR_MODE_0 BIT(0) |
| |
| /* Open Aliance 1000BaseT1 compatible HDD.TDR Fault Status Register */ |
| #define DP83TG720S_TDR_FAULT_STATUS 0x30f |
| |
| /* Register 0x0301: TDR Configuration 2 */ |
| #define DP83TG720S_TDR_CFG2 0x301 |
| |
| /* Register 0x0303: TDR Configuration 3 */ |
| #define DP83TG720S_TDR_CFG3 0x303 |
| |
| /* Register 0x0304: TDR Configuration 4 */ |
| #define DP83TG720S_TDR_CFG4 0x304 |
| |
| /* Register 0x0405: Unknown Register */ |
| #define DP83TG720S_UNKNOWN_0405 0x405 |
| |
| #define DP83TG720S_LINK_QUAL_3 0x547 |
| #define DP83TG720S_LINK_LOSS_CNT_MASK GENMASK(15, 10) |
| |
| /* Register 0x0576: TDR Master Link Down Control */ |
| #define DP83TG720S_TDR_MASTER_LINK_DOWN 0x576 |
| |
| #define DP83TG720S_RGMII_DELAY_CTRL 0x602 |
| /* In RGMII mode, Enable or disable the internal delay for RXD */ |
| #define DP83TG720S_RGMII_RX_CLK_SEL BIT(1) |
| /* In RGMII mode, Enable or disable the internal delay for TXD */ |
| #define DP83TG720S_RGMII_TX_CLK_SEL BIT(0) |
| |
| /* |
| * DP83TG720S_PKT_STAT_x registers correspond to similarly named registers |
| * in the datasheet (PKT_STAT_1 through PKT_STAT_6). These registers store |
| * 32-bit or 16-bit counters for TX and RX statistics and must be read in |
| * sequence to ensure the counters are cleared correctly. |
| * |
| * - DP83TG720S_PKT_STAT_1: Contains TX packet count bits [15:0]. |
| * - DP83TG720S_PKT_STAT_2: Contains TX packet count bits [31:16]. |
| * - DP83TG720S_PKT_STAT_3: Contains TX error packet count. |
| * - DP83TG720S_PKT_STAT_4: Contains RX packet count bits [15:0]. |
| * - DP83TG720S_PKT_STAT_5: Contains RX packet count bits [31:16]. |
| * - DP83TG720S_PKT_STAT_6: Contains RX error packet count. |
| * |
| * Keeping the register names as defined in the datasheet helps maintain |
| * clarity and alignment with the documentation. |
| */ |
| #define DP83TG720S_PKT_STAT_1 0x639 |
| #define DP83TG720S_PKT_STAT_2 0x63a |
| #define DP83TG720S_PKT_STAT_3 0x63b |
| #define DP83TG720S_PKT_STAT_4 0x63c |
| #define DP83TG720S_PKT_STAT_5 0x63d |
| #define DP83TG720S_PKT_STAT_6 0x63e |
| |
| /* Register 0x083F: Unknown Register */ |
| #define DP83TG720S_UNKNOWN_083F 0x83f |
| |
| #define DP83TG720S_SQI_REG_1 0x871 |
| #define DP83TG720S_SQI_OUT_WORST GENMASK(7, 5) |
| #define DP83TG720S_SQI_OUT GENMASK(3, 1) |
| |
| #define DP83TG720_SQI_MAX 7 |
| |
| struct dp83tg720_stats { |
| u64 link_loss_cnt; |
| u64 tx_pkt_cnt; |
| u64 tx_err_pkt_cnt; |
| u64 rx_pkt_cnt; |
| u64 rx_err_pkt_cnt; |
| }; |
| |
| struct dp83tg720_priv { |
| struct dp83tg720_stats stats; |
| unsigned long last_link_down_jiffies; |
| }; |
| |
| /** |
| * dp83tg720_update_stats - Update the PHY statistics for the DP83TD510 PHY. |
| * @phydev: Pointer to the phy_device structure. |
| * |
| * The function reads the PHY statistics registers and updates the statistics |
| * structure. |
| * |
| * Returns: 0 on success or a negative error code on failure. |
| */ |
| static int dp83tg720_update_stats(struct phy_device *phydev) |
| { |
| struct dp83tg720_priv *priv = phydev->priv; |
| u32 count; |
| int ret; |
| |
| /* Read the link loss count */ |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_LINK_QUAL_3); |
| if (ret < 0) |
| return ret; |
| /* link_loss_cnt */ |
| count = FIELD_GET(DP83TG720S_LINK_LOSS_CNT_MASK, ret); |
| priv->stats.link_loss_cnt += count; |
| |
| /* The DP83TG720S_PKT_STAT registers are divided into two groups: |
| * - Group 1 (TX stats): DP83TG720S_PKT_STAT_1 to DP83TG720S_PKT_STAT_3 |
| * - Group 2 (RX stats): DP83TG720S_PKT_STAT_4 to DP83TG720S_PKT_STAT_6 |
| * |
| * Registers in each group are cleared only after reading them in a |
| * plain sequence (e.g., 1, 2, 3 for Group 1 or 4, 5, 6 for Group 2). |
| * Any deviation from the sequence, such as reading 1, 2, 1, 2, 3, will |
| * prevent the group from being cleared. Additionally, the counters |
| * for a group are frozen as soon as the first register in that group |
| * is accessed. |
| */ |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_1); |
| if (ret < 0) |
| return ret; |
| /* tx_pkt_cnt_15_0 */ |
| count = ret; |
| |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_2); |
| if (ret < 0) |
| return ret; |
| /* tx_pkt_cnt_31_16 */ |
| count |= ret << 16; |
| priv->stats.tx_pkt_cnt += count; |
| |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_3); |
| if (ret < 0) |
| return ret; |
| /* tx_err_pkt_cnt */ |
| priv->stats.tx_err_pkt_cnt += ret; |
| |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_4); |
| if (ret < 0) |
| return ret; |
| /* rx_pkt_cnt_15_0 */ |
| count = ret; |
| |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_5); |
| if (ret < 0) |
| return ret; |
| /* rx_pkt_cnt_31_16 */ |
| count |= ret << 16; |
| priv->stats.rx_pkt_cnt += count; |
| |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_6); |
| if (ret < 0) |
| return ret; |
| /* rx_err_pkt_cnt */ |
| priv->stats.rx_err_pkt_cnt += ret; |
| |
| return 0; |
| } |
| |
| static int dp83tg720_soft_reset(struct phy_device *phydev) |
| { |
| int ret; |
| |
| ret = phy_write(phydev, DP83TG720S_PHY_RESET, DP83TG720S_HW_RESET); |
| if (ret) |
| return ret; |
| |
| /* Include mandatory MDC-access delay (1ms) + extra asymmetric delay to |
| * avoid synchronized reset deadlock. See section 1 in the top-of-file |
| * comment block. |
| */ |
| if (phydev->master_slave_state == MASTER_SLAVE_STATE_SLAVE) |
| msleep(DP83TG720S_RESET_DELAY_MS_SLAVE); |
| else |
| msleep(DP83TG720S_RESET_DELAY_MS_MASTER); |
| |
| return ret; |
| } |
| |
| static void dp83tg720_get_link_stats(struct phy_device *phydev, |
| struct ethtool_link_ext_stats *link_stats) |
| { |
| struct dp83tg720_priv *priv = phydev->priv; |
| |
| link_stats->link_down_events = priv->stats.link_loss_cnt; |
| } |
| |
| static void dp83tg720_get_phy_stats(struct phy_device *phydev, |
| struct ethtool_eth_phy_stats *eth_stats, |
| struct ethtool_phy_stats *stats) |
| { |
| struct dp83tg720_priv *priv = phydev->priv; |
| |
| stats->tx_packets = priv->stats.tx_pkt_cnt; |
| stats->tx_errors = priv->stats.tx_err_pkt_cnt; |
| stats->rx_packets = priv->stats.rx_pkt_cnt; |
| stats->rx_errors = priv->stats.rx_err_pkt_cnt; |
| } |
| |
| /** |
| * dp83tg720_cable_test_start - Start the cable test for the DP83TG720 PHY. |
| * @phydev: Pointer to the phy_device structure. |
| * |
| * This sequence is based on the documented procedure for the DP83TG720 PHY. |
| * |
| * Returns: 0 on success, a negative error code on failure. |
| */ |
| static int dp83tg720_cable_test_start(struct phy_device *phydev) |
| { |
| int ret; |
| |
| /* Initialize the PHY to run the TDR test as described in the |
| * "DP83TG720S-Q1: Configuring for Open Alliance Specification |
| * Compliance (Rev. B)" application note. |
| * Most of the registers are not documented. Some of register names |
| * are guessed by comparing the register offsets with the DP83TD510E. |
| */ |
| |
| /* Force master link down */ |
| ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2, |
| DP83TG720S_TDR_MASTER_LINK_DOWN, 0x0400); |
| if (ret) |
| return ret; |
| |
| ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG2, |
| 0xa008); |
| if (ret) |
| return ret; |
| |
| ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG3, |
| 0x0928); |
| if (ret) |
| return ret; |
| |
| ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG4, |
| 0x0004); |
| if (ret) |
| return ret; |
| |
| ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_UNKNOWN_0405, |
| 0x6400); |
| if (ret) |
| return ret; |
| |
| ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_UNKNOWN_083F, |
| 0x3003); |
| if (ret) |
| return ret; |
| |
| /* Start the TDR */ |
| ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG, |
| DP83TG720S_TDR_START); |
| if (ret) |
| return ret; |
| |
| return 0; |
| } |
| |
| /** |
| * dp83tg720_cable_test_get_status - Get the status of the cable test for the |
| * DP83TG720 PHY. |
| * @phydev: Pointer to the phy_device structure. |
| * @finished: Pointer to a boolean that indicates whether the test is finished. |
| * |
| * The function sets the @finished flag to true if the test is complete. |
| * |
| * Returns: 0 on success or a negative error code on failure. |
| */ |
| static int dp83tg720_cable_test_get_status(struct phy_device *phydev, |
| bool *finished) |
| { |
| int ret, stat; |
| |
| *finished = false; |
| |
| /* Read the TDR status */ |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG); |
| if (ret < 0) |
| return ret; |
| |
| /* Check if the TDR test is done */ |
| if (!(ret & DP83TG720S_TDR_DONE)) |
| return 0; |
| |
| /* Check for TDR test failure */ |
| if (!(ret & DP83TG720S_TDR_FAIL)) { |
| int location; |
| |
| /* Read fault status */ |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, |
| DP83TG720S_TDR_FAULT_STATUS); |
| if (ret < 0) |
| return ret; |
| |
| /* Get fault type */ |
| stat = oa_1000bt1_get_ethtool_cable_result_code(ret); |
| |
| /* Determine fault location */ |
| location = oa_1000bt1_get_tdr_distance(ret); |
| if (location > 0) |
| ethnl_cable_test_fault_length(phydev, |
| ETHTOOL_A_CABLE_PAIR_A, |
| location); |
| } else { |
| /* Active link partner or other issues */ |
| stat = ETHTOOL_A_CABLE_RESULT_CODE_UNSPEC; |
| } |
| |
| *finished = true; |
| |
| ethnl_cable_test_result(phydev, ETHTOOL_A_CABLE_PAIR_A, stat); |
| |
| /* save the current stats before resetting the PHY */ |
| ret = dp83tg720_update_stats(phydev); |
| if (ret) |
| return ret; |
| |
| return phy_init_hw(phydev); |
| } |
| |
| static int dp83tg720_config_aneg(struct phy_device *phydev) |
| { |
| int ret; |
| |
| /* Autoneg is not supported and this PHY supports only one speed. |
| * We need to care only about master/slave configuration if it was |
| * changed by user. |
| */ |
| ret = genphy_c45_pma_baset1_setup_master_slave(phydev); |
| if (ret) |
| return ret; |
| |
| /* Re-read role configuration to make changes visible even if |
| * the link is in administrative down state. |
| */ |
| return genphy_c45_pma_baset1_read_master_slave(phydev); |
| } |
| |
| static int dp83tg720_read_status(struct phy_device *phydev) |
| { |
| u16 phy_sts; |
| int ret; |
| |
| phydev->pause = 0; |
| phydev->asym_pause = 0; |
| |
| /* Most of Clause 45 registers are not present, so we can't use |
| * genphy_c45_read_status() here. |
| */ |
| phy_sts = phy_read(phydev, DP83TG720S_MII_REG_10); |
| phydev->link = !!(phy_sts & DP83TG720S_LINK_STATUS); |
| if (!phydev->link) { |
| /* save the current stats before resetting the PHY */ |
| ret = dp83tg720_update_stats(phydev); |
| if (ret) |
| return ret; |
| |
| /* According to the "DP83TC81x, DP83TG72x Software |
| * Implementation Guide", the PHY needs to be reset after a |
| * link loss or if no link is created after at least 100ms. |
| */ |
| ret = phy_init_hw(phydev); |
| if (ret) |
| return ret; |
| |
| /* After HW reset we need to restore master/slave configuration. |
| * genphy_c45_pma_baset1_read_master_slave() call will be done |
| * by the dp83tg720_config_aneg() function. |
| */ |
| ret = dp83tg720_config_aneg(phydev); |
| if (ret) |
| return ret; |
| |
| phydev->speed = SPEED_UNKNOWN; |
| phydev->duplex = DUPLEX_UNKNOWN; |
| } else { |
| /* PMA/PMD control 1 register (Register 1.0) is present, but it |
| * doesn't contain the link speed information. |
| * So genphy_c45_read_pma() can't be used here. |
| */ |
| ret = genphy_c45_pma_baset1_read_master_slave(phydev); |
| if (ret) |
| return ret; |
| |
| phydev->duplex = DUPLEX_FULL; |
| phydev->speed = SPEED_1000; |
| } |
| |
| return 0; |
| } |
| |
| static int dp83tg720_get_sqi(struct phy_device *phydev) |
| { |
| int ret; |
| |
| if (!phydev->link) |
| return 0; |
| |
| ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_SQI_REG_1); |
| if (ret < 0) |
| return ret; |
| |
| return FIELD_GET(DP83TG720S_SQI_OUT, ret); |
| } |
| |
| static int dp83tg720_get_sqi_max(struct phy_device *phydev) |
| { |
| return DP83TG720_SQI_MAX; |
| } |
| |
| static int dp83tg720_config_rgmii_delay(struct phy_device *phydev) |
| { |
| u16 rgmii_delay_mask; |
| u16 rgmii_delay = 0; |
| |
| switch (phydev->interface) { |
| case PHY_INTERFACE_MODE_RGMII: |
| rgmii_delay = 0; |
| break; |
| case PHY_INTERFACE_MODE_RGMII_ID: |
| rgmii_delay = DP83TG720S_RGMII_RX_CLK_SEL | |
| DP83TG720S_RGMII_TX_CLK_SEL; |
| break; |
| case PHY_INTERFACE_MODE_RGMII_RXID: |
| rgmii_delay = DP83TG720S_RGMII_RX_CLK_SEL; |
| break; |
| case PHY_INTERFACE_MODE_RGMII_TXID: |
| rgmii_delay = DP83TG720S_RGMII_TX_CLK_SEL; |
| break; |
| default: |
| return 0; |
| } |
| |
| rgmii_delay_mask = DP83TG720S_RGMII_RX_CLK_SEL | |
| DP83TG720S_RGMII_TX_CLK_SEL; |
| |
| return phy_modify_mmd(phydev, MDIO_MMD_VEND2, |
| DP83TG720S_RGMII_DELAY_CTRL, rgmii_delay_mask, |
| rgmii_delay); |
| } |
| |
| static int dp83tg720_config_init(struct phy_device *phydev) |
| { |
| int ret; |
| |
| /* Reset the PHY to recover from a link failure */ |
| ret = dp83tg720_soft_reset(phydev); |
| if (ret) |
| return ret; |
| |
| if (phy_interface_is_rgmii(phydev)) { |
| ret = dp83tg720_config_rgmii_delay(phydev); |
| if (ret) |
| return ret; |
| } |
| |
| /* In case the PHY is bootstrapped in managed mode, we need to |
| * wake it. |
| */ |
| ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_LPS_CFG3, |
| DP83TG720S_LPS_CFG3_PWR_MODE_0); |
| if (ret) |
| return ret; |
| |
| /* Make role configuration visible for ethtool on init and after |
| * rest. |
| */ |
| return genphy_c45_pma_baset1_read_master_slave(phydev); |
| } |
| |
| static int dp83tg720_probe(struct phy_device *phydev) |
| { |
| struct device *dev = &phydev->mdio.dev; |
| struct dp83tg720_priv *priv; |
| |
| priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); |
| if (!priv) |
| return -ENOMEM; |
| |
| phydev->priv = priv; |
| |
| return 0; |
| } |
| |
| /** |
| * dp83tg720_get_next_update_time - Return next polling interval for PHY state |
| * @phydev: Pointer to the phy_device structure |
| * |
| * Implements adaptive polling interval logic depending on link state and |
| * downtime duration. See the "2. Polling-Based Link Detection and IRQ Support" |
| * section at the top of this file for details. |
| * |
| * Return: Time (in jiffies) until the next poll |
| */ |
| static unsigned int dp83tg720_get_next_update_time(struct phy_device *phydev) |
| { |
| struct dp83tg720_priv *priv = phydev->priv; |
| unsigned int next_time_jiffies; |
| |
| if (phydev->link) { |
| priv->last_link_down_jiffies = 0; |
| |
| /* When the link is up, use a slower interval (in jiffies) */ |
| next_time_jiffies = |
| msecs_to_jiffies(DP83TG720S_POLL_ACTIVE_LINK); |
| } else { |
| unsigned long now = jiffies; |
| |
| if (!priv->last_link_down_jiffies) |
| priv->last_link_down_jiffies = now; |
| |
| if (time_before(now, priv->last_link_down_jiffies + |
| msecs_to_jiffies(DP83TG720S_FAST_POLL_DURATION_MS))) { |
| /* Link recently went down: fast polling */ |
| next_time_jiffies = |
| msecs_to_jiffies(DP83TG720S_POLL_NO_LINK); |
| } else { |
| /* Link has been down for a while: slow polling */ |
| next_time_jiffies = |
| msecs_to_jiffies(DP83TG720S_POLL_SLOW); |
| } |
| } |
| |
| /* Ensure the polling time is at least one jiffy */ |
| return max(next_time_jiffies, 1U); |
| } |
| |
| static struct phy_driver dp83tg720_driver[] = { |
| { |
| PHY_ID_MATCH_MODEL(DP83TG720S_PHY_ID), |
| .name = "TI DP83TG720S", |
| |
| .flags = PHY_POLL_CABLE_TEST, |
| .probe = dp83tg720_probe, |
| .soft_reset = dp83tg720_soft_reset, |
| .config_aneg = dp83tg720_config_aneg, |
| .read_status = dp83tg720_read_status, |
| .get_features = genphy_c45_pma_read_ext_abilities, |
| .config_init = dp83tg720_config_init, |
| .get_sqi = dp83tg720_get_sqi, |
| .get_sqi_max = dp83tg720_get_sqi_max, |
| .cable_test_start = dp83tg720_cable_test_start, |
| .cable_test_get_status = dp83tg720_cable_test_get_status, |
| .get_link_stats = dp83tg720_get_link_stats, |
| .get_phy_stats = dp83tg720_get_phy_stats, |
| .update_stats = dp83tg720_update_stats, |
| .get_next_update_time = dp83tg720_get_next_update_time, |
| |
| .suspend = genphy_suspend, |
| .resume = genphy_resume, |
| } }; |
| module_phy_driver(dp83tg720_driver); |
| |
| static const struct mdio_device_id __maybe_unused dp83tg720_tbl[] = { |
| { PHY_ID_MATCH_MODEL(DP83TG720S_PHY_ID) }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(mdio, dp83tg720_tbl); |
| |
| MODULE_DESCRIPTION("Texas Instruments DP83TG720S PHY driver"); |
| MODULE_AUTHOR("Oleksij Rempel <kernel@pengutronix.de>"); |
| MODULE_LICENSE("GPL"); |