--- /dev/null
+// 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 <linux/spi/spi.h>
+#include <linux/mii.h>
+
+/* 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 <boja@keba.com>");
+MODULE_AUTHOR("Gerhard Engleder <eg@keba.com>");
+MODULE_DESCRIPTION("KEBA LAN9252 driver");
+MODULE_LICENSE("GPL");
projects / thirdparty / kernel / linux.git / commitdiff
