| /* |
| * Cavium ThunderX i2c driver. |
| * |
| * Copyright (C) 2015,2016 Cavium Inc. |
| * Authors: Fred Martin <fmartin@caviumnetworks.com> |
| * Jan Glauber <jglauber@cavium.com> |
| * |
| * 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 <linux/acpi.h> |
| #include <linux/clk.h> |
| #include <linux/delay.h> |
| #include <linux/i2c.h> |
| #include <linux/i2c-smbus.h> |
| #include <linux/interrupt.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/of_irq.h> |
| #include <linux/pci.h> |
| |
| #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 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) |
| { |
| u32 type; |
| |
| if (!node) |
| return -EINVAL; |
| |
| i2c->alert_data.irq = irq_of_parse_and_map(node, 0); |
| if (!i2c->alert_data.irq) |
| return -EINVAL; |
| |
| type = irqd_get_trigger_type(irq_get_irq_data(i2c->alert_data.irq)); |
| i2c->alert_data.alert_edge_triggered = |
| (type & IRQ_TYPE_LEVEL_MASK) ? 1 : 0; |
| |
| 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) |
| { |
| if (i2c->ara) |
| 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 <fmartin@caviumnetworks.com>"); |
| MODULE_DESCRIPTION("I2C-Bus adapter for Cavium ThunderX SOC"); |