/* * Cavium ThunderX i2c driver. * * Copyright (C) 2015,2016 Cavium Inc. * Authors: Fred Martin * Jan Glauber * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include #include #include #include #include #include #include #include #include #include #include "i2c-octeon-core.h" #define DRV_NAME "i2c-thunderx" #define PCI_DEVICE_ID_THUNDER_TWSI 0xa012 #define SYS_FREQ_DEFAULT 700000000 #define TWSI_INT_ENA_W1C 0x1028 #define TWSI_INT_ENA_W1S 0x1030 /* * Enable the CORE interrupt. * The interrupt will be asserted when there is non-STAT_IDLE state in the * SW_TWSI_EOP_TWSI_STAT register. */ static void thunder_i2c_int_enable(struct octeon_i2c *i2c) { octeon_i2c_writeq_flush(TWSI_INT_CORE_INT, i2c->twsi_base + TWSI_INT_ENA_W1S); } /* * Disable the CORE interrupt. */ static void thunder_i2c_int_disable(struct octeon_i2c *i2c) { octeon_i2c_writeq_flush(TWSI_INT_CORE_INT, i2c->twsi_base + TWSI_INT_ENA_W1C); } static void thunder_i2c_hlc_int_enable(struct octeon_i2c *i2c) { octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT, i2c->twsi_base + TWSI_INT_ENA_W1S); } static void thunder_i2c_hlc_int_disable(struct octeon_i2c *i2c) { octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT, i2c->twsi_base + TWSI_INT_ENA_W1C); } static u32 thunderx_i2c_functionality(struct i2c_adapter *adap) { return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL; } static const struct i2c_algorithm thunderx_i2c_algo = { .master_xfer = octeon_i2c_xfer, .functionality = thunderx_i2c_functionality, }; static const struct i2c_adapter thunderx_i2c_ops = { .owner = THIS_MODULE, .name = "ThunderX adapter", .algo = &thunderx_i2c_algo, }; static void thunder_i2c_clock_enable(struct device *dev, struct octeon_i2c *i2c) { int ret; if (acpi_disabled) { /* DT */ i2c->clk = clk_get(dev, NULL); if (IS_ERR(i2c->clk)) { i2c->clk = NULL; goto skip; } ret = clk_prepare_enable(i2c->clk); if (ret) goto skip; i2c->sys_freq = clk_get_rate(i2c->clk); } else { /* ACPI */ device_property_read_u32(dev, "sclk", &i2c->sys_freq); } skip: if (!i2c->sys_freq) i2c->sys_freq = SYS_FREQ_DEFAULT; } static void thunder_i2c_clock_disable(struct device *dev, struct clk *clk) { if (!clk) return; clk_disable_unprepare(clk); clk_put(clk); } static int thunder_i2c_smbus_setup_of(struct octeon_i2c *i2c, struct device_node *node) { if (!node) return -EINVAL; i2c->alert_data.irq = irq_of_parse_and_map(node, 0); if (!i2c->alert_data.irq) return -EINVAL; i2c->ara = i2c_setup_smbus_alert(&i2c->adap, &i2c->alert_data); if (!i2c->ara) return -ENODEV; return 0; } static int thunder_i2c_smbus_setup(struct octeon_i2c *i2c, struct device_node *node) { /* TODO: ACPI support */ if (!acpi_disabled) return -EOPNOTSUPP; return thunder_i2c_smbus_setup_of(i2c, node); } static void thunder_i2c_smbus_remove(struct octeon_i2c *i2c) { i2c_unregister_device(i2c->ara); } static int thunder_i2c_probe_pci(struct pci_dev *pdev, const struct pci_device_id *ent) { struct device *dev = &pdev->dev; struct octeon_i2c *i2c; int ret; i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); if (!i2c) return -ENOMEM; i2c->roff.sw_twsi = 0x1000; i2c->roff.twsi_int = 0x1010; i2c->roff.sw_twsi_ext = 0x1018; i2c->dev = dev; pci_set_drvdata(pdev, i2c); ret = pcim_enable_device(pdev); if (ret) return ret; ret = pci_request_regions(pdev, DRV_NAME); if (ret) return ret; i2c->twsi_base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0)); if (!i2c->twsi_base) return -EINVAL; thunder_i2c_clock_enable(dev, i2c); ret = device_property_read_u32(dev, "clock-frequency", &i2c->twsi_freq); if (ret) i2c->twsi_freq = 100000; init_waitqueue_head(&i2c->queue); i2c->int_enable = thunder_i2c_int_enable; i2c->int_disable = thunder_i2c_int_disable; i2c->hlc_int_enable = thunder_i2c_hlc_int_enable; i2c->hlc_int_disable = thunder_i2c_hlc_int_disable; ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSIX); if (ret < 0) goto error; ret = devm_request_irq(dev, pci_irq_vector(pdev, 0), octeon_i2c_isr, 0, DRV_NAME, i2c); if (ret) goto error; ret = octeon_i2c_init_lowlevel(i2c); if (ret) goto error; octeon_i2c_set_clock(i2c); i2c->adap = thunderx_i2c_ops; i2c->adap.retries = 5; i2c->adap.class = I2C_CLASS_HWMON; i2c->adap.bus_recovery_info = &octeon_i2c_recovery_info; i2c->adap.dev.parent = dev; i2c->adap.dev.of_node = pdev->dev.of_node; snprintf(i2c->adap.name, sizeof(i2c->adap.name), "Cavium ThunderX i2c adapter at %s", dev_name(dev)); i2c_set_adapdata(&i2c->adap, i2c); ret = i2c_add_adapter(&i2c->adap); if (ret) goto error; dev_info(i2c->dev, "Probed. Set system clock to %u\n", i2c->sys_freq); ret = thunder_i2c_smbus_setup(i2c, pdev->dev.of_node); if (ret) dev_info(dev, "SMBUS alert not active on this bus\n"); return 0; error: thunder_i2c_clock_disable(dev, i2c->clk); return ret; } static void thunder_i2c_remove_pci(struct pci_dev *pdev) { struct octeon_i2c *i2c = pci_get_drvdata(pdev); thunder_i2c_smbus_remove(i2c); thunder_i2c_clock_disable(&pdev->dev, i2c->clk); i2c_del_adapter(&i2c->adap); } static const struct pci_device_id thunder_i2c_pci_id_table[] = { { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, PCI_DEVICE_ID_THUNDER_TWSI) }, { 0, } }; MODULE_DEVICE_TABLE(pci, thunder_i2c_pci_id_table); static struct pci_driver thunder_i2c_pci_driver = { .name = DRV_NAME, .id_table = thunder_i2c_pci_id_table, .probe = thunder_i2c_probe_pci, .remove = thunder_i2c_remove_pci, }; module_pci_driver(thunder_i2c_pci_driver); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Fred Martin "); MODULE_DESCRIPTION("I2C-Bus adapter for Cavium ThunderX SOC");