// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) KEBA Industrial Automation Gmbh 2024 * * Driver for LAN9252 on KEBA CP500 devices * * This driver is used for updating the configuration of the LAN9252 controller * on KEBA CP500 devices. The LAN9252 is connected over SPI, which is also named * PDI. */ #include #include /* SPI commands */ #define LAN9252_SPI_READ 0x3 #define LAN9252_SPI_WRITE 0x2 struct lan9252_read_cmd { u8 cmd; u8 addr_0; u8 addr_1; } __packed; struct lan9252_write_cmd { u8 cmd; u8 addr_0; u8 addr_1; u32 data; } __packed; /* byte test register */ #define LAN9252_BYTE_TEST 0x64 #define LAN9252_BYTE_TEST_VALUE 0x87654321 /* hardware configuration register */ #define LAN9252_HW_CFG 0x74 #define LAN9252_HW_CFG_READY 0x08000000 /* EtherCAT CSR interface data register */ #define LAN9252_ECAT_CSR_DATA 0x300 /* EtherCAT CSR interface command register */ #define LAN9252_ECAT_CSR_CMD 0x304 #define LAN9252_ECAT_CSR_BUSY 0x80000000 #define LAN9252_ECAT_CSR_READ 0x40000000 /* EtherCAT slave controller MII register */ #define LAN9252_ESC_MII 0x510 #define LAN9252_ESC_MII_BUSY 0x8000 #define LAN9252_ESC_MII_CMD_ERR 0x4000 #define LAN9252_ESC_MII_READ_ERR 0x2000 #define LAN9252_ESC_MII_ERR_MASK (LAN9252_ESC_MII_CMD_ERR | \ LAN9252_ESC_MII_READ_ERR) #define LAN9252_ESC_MII_WRITE 0x0200 #define LAN9252_ESC_MII_READ 0x0100 /* EtherCAT slave controller PHY address register */ #define LAN9252_ESC_PHY_ADDR 0x512 /* EtherCAT slave controller PHY register address register */ #define LAN9252_ESC_PHY_REG_ADDR 0x513 /* EtherCAT slave controller PHY data register */ #define LAN9252_ESC_PHY_DATA 0x514 /* EtherCAT slave controller PDI access state register */ #define LAN9252_ESC_MII_PDI 0x517 #define LAN9252_ESC_MII_ACCESS_PDI 0x01 #define LAN9252_ESC_MII_ACCESS_ECAT 0x00 /* PHY address */ #define PHY_ADDRESS 2 #define SPI_RETRY_COUNT 10 #define SPI_WAIT_US 100 #define SPI_CSR_WAIT_US 500 static int lan9252_spi_read(struct spi_device *spi, u16 addr, u32 *data) { struct lan9252_read_cmd cmd; cmd.cmd = LAN9252_SPI_READ; cmd.addr_0 = (addr >> 8) & 0xFF; cmd.addr_1 = addr & 0xFF; return spi_write_then_read(spi, (u8 *)&cmd, sizeof(struct lan9252_read_cmd), (u8 *)data, sizeof(u32)); } static int lan9252_spi_write(struct spi_device *spi, u16 addr, u32 data) { struct lan9252_write_cmd cmd; cmd.cmd = LAN9252_SPI_WRITE; cmd.addr_0 = (addr >> 8) & 0xFF; cmd.addr_1 = addr & 0xFF; cmd.data = data; return spi_write(spi, (u8 *)&cmd, sizeof(struct lan9252_write_cmd)); } static bool lan9252_init(struct spi_device *spi) { u32 data; int ret; ret = lan9252_spi_read(spi, LAN9252_BYTE_TEST, &data); if (ret || data != LAN9252_BYTE_TEST_VALUE) return false; ret = lan9252_spi_read(spi, LAN9252_HW_CFG, &data); if (ret || !(data & LAN9252_HW_CFG_READY)) return false; return true; } static u8 lan9252_esc_get_size(u16 addr) { if (addr == LAN9252_ESC_MII || addr == LAN9252_ESC_PHY_DATA) return 2; return 1; } static int lan9252_esc_wait(struct spi_device *spi) { ktime_t timeout = ktime_add_us(ktime_get(), SPI_WAIT_US); u32 data; int ret; /* wait while CSR command is busy */ for (;;) { ret = lan9252_spi_read(spi, LAN9252_ECAT_CSR_CMD, &data); if (ret) return ret; if (!(data & LAN9252_ECAT_CSR_BUSY)) return 0; if (ktime_compare(ktime_get(), timeout) > 0) { ret = lan9252_spi_read(spi, LAN9252_ECAT_CSR_CMD, &data); if (ret) return ret; break; } } return (!(data & LAN9252_ECAT_CSR_BUSY)) ? 0 : -ETIMEDOUT; } static int lan9252_esc_read(struct spi_device *spi, u16 addr, u32 *data) { u32 csr_cmd; u8 size; int ret; size = lan9252_esc_get_size(addr); csr_cmd = LAN9252_ECAT_CSR_BUSY | LAN9252_ECAT_CSR_READ; csr_cmd |= (size << 16) | addr; ret = lan9252_spi_write(spi, LAN9252_ECAT_CSR_CMD, csr_cmd); if (ret) return ret; ret = lan9252_esc_wait(spi); if (ret) return ret; ret = lan9252_spi_read(spi, LAN9252_ECAT_CSR_DATA, data); if (ret) return ret; return 0; } static int lan9252_esc_write(struct spi_device *spi, u16 addr, u32 data) { u32 csr_cmd; u8 size; int ret; ret = lan9252_spi_write(spi, LAN9252_ECAT_CSR_DATA, data); if (ret) return ret; size = lan9252_esc_get_size(addr); csr_cmd = LAN9252_ECAT_CSR_BUSY; csr_cmd |= (size << 16) | addr; ret = lan9252_spi_write(spi, LAN9252_ECAT_CSR_CMD, csr_cmd); if (ret) return ret; ret = lan9252_esc_wait(spi); if (ret) return ret; return 0; } static int lan9252_access_mii(struct spi_device *spi, bool access) { u32 data; if (access) data = LAN9252_ESC_MII_ACCESS_PDI; else data = LAN9252_ESC_MII_ACCESS_ECAT; return lan9252_esc_write(spi, LAN9252_ESC_MII_PDI, data); } static int lan9252_mii_wait(struct spi_device *spi) { ktime_t timeout = ktime_add_us(ktime_get(), SPI_CSR_WAIT_US); u32 data; int ret; /* wait while MII control state machine is busy */ for (;;) { ret = lan9252_esc_read(spi, LAN9252_ESC_MII, &data); if (ret) return ret; if (data & LAN9252_ESC_MII_ERR_MASK) return -EIO; if (!(data & LAN9252_ESC_MII_BUSY)) return 0; if (ktime_compare(ktime_get(), timeout) > 0) { ret = lan9252_esc_read(spi, LAN9252_ESC_MII, &data); if (ret) return ret; if (data & LAN9252_ESC_MII_ERR_MASK) return -EIO; break; } } return (!(data & LAN9252_ESC_MII_BUSY)) ? 0 : -ETIMEDOUT; } static int lan9252_mii_read(struct spi_device *spi, u8 phy_addr, u8 reg_addr, u32 *data) { int ret; ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_ADDR, phy_addr); if (ret) return ret; ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_REG_ADDR, reg_addr); if (ret) return ret; ret = lan9252_esc_write(spi, LAN9252_ESC_MII, LAN9252_ESC_MII_READ); if (ret) return ret; ret = lan9252_mii_wait(spi); if (ret) return ret; return lan9252_esc_read(spi, LAN9252_ESC_PHY_DATA, data); } static int lan9252_mii_write(struct spi_device *spi, u8 phy_addr, u8 reg_addr, u32 data) { int ret; ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_ADDR, phy_addr); if (ret) return ret; ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_REG_ADDR, reg_addr); if (ret) return ret; ret = lan9252_esc_write(spi, LAN9252_ESC_PHY_DATA, data); if (ret) return ret; ret = lan9252_esc_write(spi, LAN9252_ESC_MII, LAN9252_ESC_MII_WRITE); if (ret) return ret; return lan9252_mii_wait(spi); } static int lan9252_probe(struct spi_device *spi) { u32 data; int retry = SPI_RETRY_COUNT; int ret; /* execute specified initialization sequence */ while (retry && !lan9252_init(spi)) retry--; if (retry == 0) { dev_err(&spi->dev, "Can't initialize LAN9252 SPI communication!"); return -EIO; } /* enable access to MII management for PDI */ ret = lan9252_access_mii(spi, true); if (ret) { dev_err(&spi->dev, "Can't enable access to MII management!"); return ret; } /* * check PHY configuration and configure if necessary * - full duplex * - auto negotiation disabled * - 100 Mbps */ ret = lan9252_mii_read(spi, PHY_ADDRESS, MII_BMCR, &data); if (ret) { dev_err(&spi->dev, "Can't read LAN9252 configuration!"); goto out; } if (!(data & BMCR_FULLDPLX) || (data & BMCR_ANENABLE) || !(data & BMCR_SPEED100)) { /* */ data &= ~(BMCR_ANENABLE); data |= (BMCR_FULLDPLX | BMCR_SPEED100); ret = lan9252_mii_write(spi, PHY_ADDRESS, MII_BMCR, data); if (ret) dev_err(&spi->dev, "Can't write LAN9252 configuration!"); } dev_info(&spi->dev, "LAN9252 PHY configuration"); out: /* disable access to MII management for PDI */ lan9252_access_mii(spi, false); return ret; } static const struct spi_device_id lan9252_id[] = { {"lan9252"}, {} }; MODULE_DEVICE_TABLE(spi, lan9252_id); static struct spi_driver lan9252_driver = { .driver = { .name = "lan9252", }, .probe = lan9252_probe, .id_table = lan9252_id, }; module_spi_driver(lan9252_driver); MODULE_AUTHOR("Petar Bojanic "); MODULE_AUTHOR("Gerhard Engleder "); MODULE_DESCRIPTION("KEBA LAN9252 driver"); MODULE_LICENSE("GPL");