| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Jean Delvare | 902 | 86.73% | 3 | 17.65% |
| Phil Reid | 72 | 6.92% | 2 | 11.76% |
| Benjamin Tissoires | 20 | 1.92% | 2 | 11.76% |
| Lars-Peter Clausen | 19 | 1.83% | 1 | 5.88% |
| Wolfram Sang | 8 | 0.77% | 2 | 11.76% |
| Julia Lawall | 7 | 0.67% | 1 | 5.88% |
| Jingoo Han | 4 | 0.38% | 1 | 5.88% |
| Tejun Heo | 2 | 0.19% | 1 | 5.88% |
| Fabio Estevam | 2 | 0.19% | 1 | 5.88% |
| Stephen Rothwell | 2 | 0.19% | 1 | 5.88% |
| Thomas Gleixner | 1 | 0.10% | 1 | 5.88% |
| Shailendra Verma | 1 | 0.10% | 1 | 5.88% |
| Total | 1040 | 17 |
// SPDX-License-Identifier: GPL-2.0-or-later /* * i2c-smbus.c - SMBus extensions to the I2C protocol * * Copyright (C) 2008 David Brownell * Copyright (C) 2010-2019 Jean Delvare <jdelvare@suse.de> */ #include <linux/device.h> #include <linux/dmi.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/slab.h> #include <linux/workqueue.h> struct i2c_smbus_alert { struct work_struct alert; struct i2c_client *ara; /* Alert response address */ }; struct alert_data { unsigned short addr; enum i2c_alert_protocol type; unsigned int data; }; /* If this is the alerting device, notify its driver */ static int smbus_do_alert(struct device *dev, void *addrp) { struct i2c_client *client = i2c_verify_client(dev); struct alert_data *data = addrp; struct i2c_driver *driver; if (!client || client->addr != data->addr) return 0; if (client->flags & I2C_CLIENT_TEN) return 0; /* * Drivers should either disable alerts, or provide at least * a minimal handler. Lock so the driver won't change. */ device_lock(dev); if (client->dev.driver) { driver = to_i2c_driver(client->dev.driver); if (driver->alert) driver->alert(client, data->type, data->data); else dev_warn(&client->dev, "no driver alert()!\n"); } else dev_dbg(&client->dev, "alert with no driver\n"); device_unlock(dev); /* Stop iterating after we find the device */ return -EBUSY; } /* * The alert IRQ handler needs to hand work off to a task which can issue * SMBus calls, because those sleeping calls can't be made in IRQ context. */ static irqreturn_t smbus_alert(int irq, void *d) { struct i2c_smbus_alert *alert = d; struct i2c_client *ara; ara = alert->ara; for (;;) { s32 status; struct alert_data data; /* * Devices with pending alerts reply in address order, low * to high, because of slave transmit arbitration. After * responding, an SMBus device stops asserting SMBALERT#. * * Note that SMBus 2.0 reserves 10-bit addresses for future * use. We neither handle them, nor try to use PEC here. */ status = i2c_smbus_read_byte(ara); if (status < 0) break; data.data = status & 1; data.addr = status >> 1; data.type = I2C_PROTOCOL_SMBUS_ALERT; dev_dbg(&ara->dev, "SMBALERT# from dev 0x%02x, flag %d\n", data.addr, data.data); /* Notify driver for the device which issued the alert */ device_for_each_child(&ara->adapter->dev, &data, smbus_do_alert); } return IRQ_HANDLED; } static void smbalert_work(struct work_struct *work) { struct i2c_smbus_alert *alert; alert = container_of(work, struct i2c_smbus_alert, alert); smbus_alert(0, alert); } /* Setup SMBALERT# infrastructure */ static int smbalert_probe(struct i2c_client *ara, const struct i2c_device_id *id) { struct i2c_smbus_alert_setup *setup = dev_get_platdata(&ara->dev); struct i2c_smbus_alert *alert; struct i2c_adapter *adapter = ara->adapter; int res, irq; alert = devm_kzalloc(&ara->dev, sizeof(struct i2c_smbus_alert), GFP_KERNEL); if (!alert) return -ENOMEM; if (setup) { irq = setup->irq; } else { irq = of_irq_get_byname(adapter->dev.of_node, "smbus_alert"); if (irq <= 0) return irq; } INIT_WORK(&alert->alert, smbalert_work); alert->ara = ara; if (irq > 0) { res = devm_request_threaded_irq(&ara->dev, irq, NULL, smbus_alert, IRQF_SHARED | IRQF_ONESHOT, "smbus_alert", alert); if (res) return res; } i2c_set_clientdata(ara, alert); dev_info(&adapter->dev, "supports SMBALERT#\n"); return 0; } /* IRQ and memory resources are managed so they are freed automatically */ static int smbalert_remove(struct i2c_client *ara) { struct i2c_smbus_alert *alert = i2c_get_clientdata(ara); cancel_work_sync(&alert->alert); return 0; } static const struct i2c_device_id smbalert_ids[] = { { "smbus_alert", 0 }, { /* LIST END */ } }; MODULE_DEVICE_TABLE(i2c, smbalert_ids); static struct i2c_driver smbalert_driver = { .driver = { .name = "smbus_alert", }, .probe = smbalert_probe, .remove = smbalert_remove, .id_table = smbalert_ids, }; /** * i2c_handle_smbus_alert - Handle an SMBus alert * @ara: the ARA client on the relevant adapter * Context: can't sleep * * Helper function to be called from an I2C bus driver's interrupt * handler. It will schedule the alert work, in turn calling the * corresponding I2C device driver's alert function. * * It is assumed that ara is a valid i2c client previously returned by * i2c_new_smbus_alert_device(). */ int i2c_handle_smbus_alert(struct i2c_client *ara) { struct i2c_smbus_alert *alert = i2c_get_clientdata(ara); return schedule_work(&alert->alert); } EXPORT_SYMBOL_GPL(i2c_handle_smbus_alert); module_i2c_driver(smbalert_driver); /* * SPD is not part of SMBus but we include it here for convenience as the * target systems are the same. * Restrictions to automatic SPD instantiation: * - Only works if all filled slots have the same memory type * - Only works for DDR2, DDR3 and DDR4 for now * - Only works on systems with 1 to 4 memory slots */ #if IS_ENABLED(CONFIG_DMI) void i2c_register_spd(struct i2c_adapter *adap) { int n, slot_count = 0, dimm_count = 0; u16 handle; u8 common_mem_type = 0x0, mem_type; u64 mem_size; const char *name; while ((handle = dmi_memdev_handle(slot_count)) != 0xffff) { slot_count++; /* Skip empty slots */ mem_size = dmi_memdev_size(handle); if (!mem_size) continue; /* Skip undefined memory type */ mem_type = dmi_memdev_type(handle); if (mem_type <= 0x02) /* Invalid, Other, Unknown */ continue; if (!common_mem_type) { /* First filled slot */ common_mem_type = mem_type; } else { /* Check that all filled slots have the same type */ if (mem_type != common_mem_type) { dev_warn(&adap->dev, "Different memory types mixed, not instantiating SPD\n"); return; } } dimm_count++; } /* No useful DMI data, bail out */ if (!dimm_count) return; dev_info(&adap->dev, "%d/%d memory slots populated (from DMI)\n", dimm_count, slot_count); if (slot_count > 4) { dev_warn(&adap->dev, "Systems with more than 4 memory slots not supported yet, not instantiating SPD\n"); return; } switch (common_mem_type) { case 0x13: /* DDR2 */ case 0x18: /* DDR3 */ case 0x1C: /* LPDDR2 */ case 0x1D: /* LPDDR3 */ name = "spd"; break; case 0x1A: /* DDR4 */ case 0x1E: /* LPDDR4 */ name = "ee1004"; break; default: dev_info(&adap->dev, "Memory type 0x%02x not supported yet, not instantiating SPD\n", common_mem_type); return; } /* * We don't know in which slots the memory modules are. We could * try to guess from the slot names, but that would be rather complex * and unreliable, so better probe all possible addresses until we * have found all memory modules. */ for (n = 0; n < slot_count && dimm_count; n++) { struct i2c_board_info info; unsigned short addr_list[2]; memset(&info, 0, sizeof(struct i2c_board_info)); strlcpy(info.type, name, I2C_NAME_SIZE); addr_list[0] = 0x50 + n; addr_list[1] = I2C_CLIENT_END; if (!IS_ERR(i2c_new_scanned_device(adap, &info, addr_list, NULL))) { dev_info(&adap->dev, "Successfully instantiated SPD at 0x%hx\n", addr_list[0]); dimm_count--; } } } EXPORT_SYMBOL_GPL(i2c_register_spd); #endif MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>"); MODULE_DESCRIPTION("SMBus protocol extensions support"); MODULE_LICENSE("GPL");