Jan Glauber | 22d4020 | 2016-08-24 23:25:44 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Cavium ThunderX i2c driver. |
| 3 | * |
| 4 | * Copyright (C) 2015,2016 Cavium Inc. |
| 5 | * Authors: Fred Martin <fmartin@caviumnetworks.com> |
| 6 | * Jan Glauber <jglauber@cavium.com> |
| 7 | * |
| 8 | * This file is licensed under the terms of the GNU General Public |
| 9 | * License version 2. This program is licensed "as is" without any |
| 10 | * warranty of any kind, whether express or implied. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/acpi.h> |
| 14 | #include <linux/clk.h> |
| 15 | #include <linux/delay.h> |
| 16 | #include <linux/i2c.h> |
Jan Glauber | 1e58667 | 2016-08-24 23:25:45 +0200 | [diff] [blame] | 17 | #include <linux/i2c-smbus.h> |
Jan Glauber | 22d4020 | 2016-08-24 23:25:44 +0200 | [diff] [blame] | 18 | #include <linux/interrupt.h> |
| 19 | #include <linux/kernel.h> |
| 20 | #include <linux/module.h> |
Jan Glauber | 1e58667 | 2016-08-24 23:25:45 +0200 | [diff] [blame] | 21 | #include <linux/of_irq.h> |
Jan Glauber | 22d4020 | 2016-08-24 23:25:44 +0200 | [diff] [blame] | 22 | #include <linux/pci.h> |
| 23 | |
| 24 | #include "i2c-octeon-core.h" |
| 25 | |
| 26 | #define DRV_NAME "i2c-thunderx" |
| 27 | |
| 28 | #define PCI_DEVICE_ID_THUNDER_TWSI 0xa012 |
| 29 | |
| 30 | #define SYS_FREQ_DEFAULT 700000000 |
| 31 | |
| 32 | #define TWSI_INT_ENA_W1C 0x1028 |
| 33 | #define TWSI_INT_ENA_W1S 0x1030 |
| 34 | |
| 35 | /* |
| 36 | * Enable the CORE interrupt. |
| 37 | * The interrupt will be asserted when there is non-STAT_IDLE state in the |
| 38 | * SW_TWSI_EOP_TWSI_STAT register. |
| 39 | */ |
| 40 | static void thunder_i2c_int_enable(struct octeon_i2c *i2c) |
| 41 | { |
| 42 | octeon_i2c_writeq_flush(TWSI_INT_CORE_INT, |
| 43 | i2c->twsi_base + TWSI_INT_ENA_W1S); |
| 44 | } |
| 45 | |
| 46 | /* |
| 47 | * Disable the CORE interrupt. |
| 48 | */ |
| 49 | static void thunder_i2c_int_disable(struct octeon_i2c *i2c) |
| 50 | { |
| 51 | octeon_i2c_writeq_flush(TWSI_INT_CORE_INT, |
| 52 | i2c->twsi_base + TWSI_INT_ENA_W1C); |
| 53 | } |
| 54 | |
| 55 | static void thunder_i2c_hlc_int_enable(struct octeon_i2c *i2c) |
| 56 | { |
| 57 | octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT, |
| 58 | i2c->twsi_base + TWSI_INT_ENA_W1S); |
| 59 | } |
| 60 | |
| 61 | static void thunder_i2c_hlc_int_disable(struct octeon_i2c *i2c) |
| 62 | { |
| 63 | octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT, |
| 64 | i2c->twsi_base + TWSI_INT_ENA_W1C); |
| 65 | } |
| 66 | |
| 67 | static u32 thunderx_i2c_functionality(struct i2c_adapter *adap) |
| 68 | { |
| 69 | return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) | |
| 70 | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL; |
| 71 | } |
| 72 | |
| 73 | static const struct i2c_algorithm thunderx_i2c_algo = { |
| 74 | .master_xfer = octeon_i2c_xfer, |
| 75 | .functionality = thunderx_i2c_functionality, |
| 76 | }; |
| 77 | |
| 78 | static struct i2c_adapter thunderx_i2c_ops = { |
| 79 | .owner = THIS_MODULE, |
| 80 | .name = "ThunderX adapter", |
| 81 | .algo = &thunderx_i2c_algo, |
| 82 | }; |
| 83 | |
| 84 | static void thunder_i2c_clock_enable(struct device *dev, struct octeon_i2c *i2c) |
| 85 | { |
| 86 | int ret; |
| 87 | |
| 88 | i2c->clk = clk_get(dev, NULL); |
| 89 | if (IS_ERR(i2c->clk)) { |
| 90 | i2c->clk = NULL; |
| 91 | goto skip; |
| 92 | } |
| 93 | |
| 94 | ret = clk_prepare_enable(i2c->clk); |
| 95 | if (ret) |
| 96 | goto skip; |
| 97 | i2c->sys_freq = clk_get_rate(i2c->clk); |
| 98 | |
| 99 | skip: |
| 100 | if (!i2c->sys_freq) |
| 101 | i2c->sys_freq = SYS_FREQ_DEFAULT; |
| 102 | } |
| 103 | |
| 104 | static void thunder_i2c_clock_disable(struct device *dev, struct clk *clk) |
| 105 | { |
| 106 | if (!clk) |
| 107 | return; |
| 108 | clk_disable_unprepare(clk); |
| 109 | clk_put(clk); |
| 110 | } |
| 111 | |
Jan Glauber | 1e58667 | 2016-08-24 23:25:45 +0200 | [diff] [blame] | 112 | static int thunder_i2c_smbus_setup_of(struct octeon_i2c *i2c, |
| 113 | struct device_node *node) |
| 114 | { |
| 115 | u32 type; |
| 116 | |
| 117 | if (!node) |
| 118 | return -EINVAL; |
| 119 | |
| 120 | i2c->alert_data.irq = irq_of_parse_and_map(node, 0); |
| 121 | if (!i2c->alert_data.irq) |
| 122 | return -EINVAL; |
| 123 | |
| 124 | type = irqd_get_trigger_type(irq_get_irq_data(i2c->alert_data.irq)); |
| 125 | i2c->alert_data.alert_edge_triggered = |
| 126 | (type & IRQ_TYPE_LEVEL_MASK) ? 1 : 0; |
| 127 | |
| 128 | i2c->ara = i2c_setup_smbus_alert(&i2c->adap, &i2c->alert_data); |
| 129 | if (!i2c->ara) |
| 130 | return -ENODEV; |
| 131 | return 0; |
| 132 | } |
| 133 | |
| 134 | static int thunder_i2c_smbus_setup(struct octeon_i2c *i2c, |
| 135 | struct device_node *node) |
| 136 | { |
| 137 | /* TODO: ACPI support */ |
| 138 | if (!acpi_disabled) |
| 139 | return -EOPNOTSUPP; |
| 140 | |
| 141 | return thunder_i2c_smbus_setup_of(i2c, node); |
| 142 | } |
| 143 | |
| 144 | static void thunder_i2c_smbus_remove(struct octeon_i2c *i2c) |
| 145 | { |
| 146 | if (i2c->ara) |
| 147 | i2c_unregister_device(i2c->ara); |
| 148 | } |
| 149 | |
Jan Glauber | 22d4020 | 2016-08-24 23:25:44 +0200 | [diff] [blame] | 150 | static int thunder_i2c_probe_pci(struct pci_dev *pdev, |
| 151 | const struct pci_device_id *ent) |
| 152 | { |
| 153 | struct device *dev = &pdev->dev; |
| 154 | struct octeon_i2c *i2c; |
| 155 | int ret; |
| 156 | |
| 157 | i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); |
| 158 | if (!i2c) |
| 159 | return -ENOMEM; |
| 160 | |
Jan Glauber | 97d9700 | 2016-08-24 23:25:46 +0200 | [diff] [blame] | 161 | i2c->roff.sw_twsi = 0x1000; |
| 162 | i2c->roff.twsi_int = 0x1010; |
| 163 | i2c->roff.sw_twsi_ext = 0x1018; |
| 164 | |
Jan Glauber | 22d4020 | 2016-08-24 23:25:44 +0200 | [diff] [blame] | 165 | i2c->dev = dev; |
| 166 | pci_set_drvdata(pdev, i2c); |
| 167 | ret = pcim_enable_device(pdev); |
| 168 | if (ret) |
| 169 | return ret; |
| 170 | |
| 171 | ret = pci_request_regions(pdev, DRV_NAME); |
| 172 | if (ret) |
| 173 | return ret; |
| 174 | |
| 175 | i2c->twsi_base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0)); |
| 176 | if (!i2c->twsi_base) |
| 177 | return -EINVAL; |
| 178 | |
| 179 | thunder_i2c_clock_enable(dev, i2c); |
| 180 | ret = device_property_read_u32(dev, "clock-frequency", &i2c->twsi_freq); |
| 181 | if (ret) |
| 182 | i2c->twsi_freq = 100000; |
| 183 | |
| 184 | init_waitqueue_head(&i2c->queue); |
| 185 | |
| 186 | i2c->int_enable = thunder_i2c_int_enable; |
| 187 | i2c->int_disable = thunder_i2c_int_disable; |
| 188 | i2c->hlc_int_enable = thunder_i2c_hlc_int_enable; |
| 189 | i2c->hlc_int_disable = thunder_i2c_hlc_int_disable; |
| 190 | |
| 191 | ret = pci_enable_msix(pdev, &i2c->i2c_msix, 1); |
| 192 | if (ret) |
| 193 | goto error; |
| 194 | |
| 195 | ret = devm_request_irq(dev, i2c->i2c_msix.vector, octeon_i2c_isr, 0, |
| 196 | DRV_NAME, i2c); |
| 197 | if (ret) |
| 198 | goto error; |
| 199 | |
| 200 | ret = octeon_i2c_init_lowlevel(i2c); |
| 201 | if (ret) |
| 202 | goto error; |
| 203 | |
| 204 | octeon_i2c_set_clock(i2c); |
| 205 | |
| 206 | i2c->adap = thunderx_i2c_ops; |
| 207 | i2c->adap.retries = 5; |
| 208 | i2c->adap.bus_recovery_info = &octeon_i2c_recovery_info; |
| 209 | i2c->adap.dev.parent = dev; |
| 210 | i2c->adap.dev.of_node = pdev->dev.of_node; |
| 211 | snprintf(i2c->adap.name, sizeof(i2c->adap.name), |
| 212 | "Cavium ThunderX i2c adapter at %s", dev_name(dev)); |
| 213 | i2c_set_adapdata(&i2c->adap, i2c); |
| 214 | |
| 215 | ret = i2c_add_adapter(&i2c->adap); |
| 216 | if (ret) |
| 217 | goto error; |
| 218 | |
| 219 | dev_info(i2c->dev, "Probed. Set system clock to %u\n", i2c->sys_freq); |
Jan Glauber | 1e58667 | 2016-08-24 23:25:45 +0200 | [diff] [blame] | 220 | |
| 221 | ret = thunder_i2c_smbus_setup(i2c, pdev->dev.of_node); |
| 222 | if (ret) |
| 223 | dev_info(dev, "SMBUS alert not active on this bus\n"); |
| 224 | |
Jan Glauber | 22d4020 | 2016-08-24 23:25:44 +0200 | [diff] [blame] | 225 | return 0; |
| 226 | |
| 227 | error: |
| 228 | thunder_i2c_clock_disable(dev, i2c->clk); |
| 229 | return ret; |
| 230 | } |
| 231 | |
| 232 | static void thunder_i2c_remove_pci(struct pci_dev *pdev) |
| 233 | { |
| 234 | struct octeon_i2c *i2c = pci_get_drvdata(pdev); |
| 235 | |
Jan Glauber | 1e58667 | 2016-08-24 23:25:45 +0200 | [diff] [blame] | 236 | thunder_i2c_smbus_remove(i2c); |
Jan Glauber | 22d4020 | 2016-08-24 23:25:44 +0200 | [diff] [blame] | 237 | thunder_i2c_clock_disable(&pdev->dev, i2c->clk); |
| 238 | i2c_del_adapter(&i2c->adap); |
| 239 | } |
| 240 | |
| 241 | static const struct pci_device_id thunder_i2c_pci_id_table[] = { |
| 242 | { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, PCI_DEVICE_ID_THUNDER_TWSI) }, |
| 243 | { 0, } |
| 244 | }; |
| 245 | |
| 246 | MODULE_DEVICE_TABLE(pci, thunder_i2c_pci_id_table); |
| 247 | |
| 248 | static struct pci_driver thunder_i2c_pci_driver = { |
| 249 | .name = DRV_NAME, |
| 250 | .id_table = thunder_i2c_pci_id_table, |
| 251 | .probe = thunder_i2c_probe_pci, |
| 252 | .remove = thunder_i2c_remove_pci, |
| 253 | }; |
| 254 | |
| 255 | module_pci_driver(thunder_i2c_pci_driver); |
| 256 | |
| 257 | MODULE_LICENSE("GPL"); |
| 258 | MODULE_AUTHOR("Fred Martin <fmartin@caviumnetworks.com>"); |
| 259 | MODULE_DESCRIPTION("I2C-Bus adapter for Cavium ThunderX SOC"); |