/* i2c Support for Apple SMU Controller Copyright (c) 2005 Benjamin Herrenschmidt, IBM Corp. <benh@kernel.crashing.org> This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/types.h> #include <linux/i2c.h> #include <linux/device.h> #include <linux/platform_device.h> #include <linux/of_irq.h> #include <asm/prom.h> #include <asm/pmac_low_i2c.h> MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); MODULE_DESCRIPTION("I2C driver for Apple PowerMac"); MODULE_LICENSE("GPL"); /* * SMBUS-type transfer entrypoint */ static s32 i2c_powermac_smbus_xfer( struct i2c_adapter* adap, u16 addr, unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data* data) { struct pmac_i2c_bus *bus = i2c_get_adapdata(adap); int rc = 0; int read = (read_write == I2C_SMBUS_READ); int addrdir = (addr << 1) | read; int mode, subsize, len; u32 subaddr; u8 *buf; u8 local[2]; if (size == I2C_SMBUS_QUICK || size == I2C_SMBUS_BYTE) { mode = pmac_i2c_mode_std; subsize = 0; subaddr = 0; } else { mode = read ? pmac_i2c_mode_combined : pmac_i2c_mode_stdsub; subsize = 1; subaddr = command; } switch (size) { case I2C_SMBUS_QUICK: buf = NULL; len = 0; break; case I2C_SMBUS_BYTE: case I2C_SMBUS_BYTE_DATA: buf = &data->byte; len = 1; break; case I2C_SMBUS_WORD_DATA: if (!read) { local[0] = data->word & 0xff; local[1] = (data->word >> 8) & 0xff; } buf = local; len = 2; break; /* Note that these are broken vs. the expected smbus API where * on reads, the length is actually returned from the function, * but I think the current API makes no sense and I don't want * any driver that I haven't verified for correctness to go * anywhere near a pmac i2c bus anyway ... * * I'm also not completely sure what kind of phases to do between * the actual command and the data (what I am _supposed_ to do that * is). For now, I assume writes are a single stream and reads have * a repeat start/addr phase (but not stop in between) */ case I2C_SMBUS_BLOCK_DATA: buf = data->block; len = data->block[0] + 1; break; case I2C_SMBUS_I2C_BLOCK_DATA: buf = &data->block[1]; len = data->block[0]; break; default: return -EINVAL; } rc = pmac_i2c_open(bus, 0); if (rc) { dev_err(&adap->dev, "Failed to open I2C, err %d\n", rc); return rc; } rc = pmac_i2c_setmode(bus, mode); if (rc) { dev_err(&adap->dev, "Failed to set I2C mode %d, err %d\n", mode, rc); goto bail; } rc = pmac_i2c_xfer(bus, addrdir, subsize, subaddr, buf, len); if (rc) { if (rc == -ENXIO) dev_dbg(&adap->dev, "I2C transfer at 0x%02x failed, size %d, " "err %d\n", addrdir >> 1, size, rc); else dev_err(&adap->dev, "I2C transfer at 0x%02x failed, size %d, " "err %d\n", addrdir >> 1, size, rc); goto bail; } if (size == I2C_SMBUS_WORD_DATA && read) { data->word = ((u16)local[1]) << 8; data->word |= local[0]; } bail: pmac_i2c_close(bus); return rc; } /* * Generic i2c master transfer entrypoint. This driver only support single * messages (for "lame i2c" transfers). Anything else should use the smbus * entry point */ static int i2c_powermac_master_xfer( struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { struct pmac_i2c_bus *bus = i2c_get_adapdata(adap); int rc = 0; int read; int addrdir; if (num != 1) { dev_err(&adap->dev, "Multi-message I2C transactions not supported\n"); return -EOPNOTSUPP; } if (msgs->flags & I2C_M_TEN) return -EINVAL; read = (msgs->flags & I2C_M_RD) != 0; addrdir = (msgs->addr << 1) | read; rc = pmac_i2c_open(bus, 0); if (rc) { dev_err(&adap->dev, "Failed to open I2C, err %d\n", rc); return rc; } rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); if (rc) { dev_err(&adap->dev, "Failed to set I2C mode %d, err %d\n", pmac_i2c_mode_std, rc); goto bail; } rc = pmac_i2c_xfer(bus, addrdir, 0, 0, msgs->buf, msgs->len); if (rc < 0) { if (rc == -ENXIO) dev_dbg(&adap->dev, "I2C %s 0x%02x failed, err %d\n", addrdir & 1 ? "read from" : "write to", addrdir >> 1, rc); else dev_err(&adap->dev, "I2C %s 0x%02x failed, err %d\n", addrdir & 1 ? "read from" : "write to", addrdir >> 1, rc); } bail: pmac_i2c_close(bus); return rc < 0 ? rc : 1; } static u32 i2c_powermac_func(struct i2c_adapter * adapter) { return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_I2C; } /* For now, we only handle smbus */ static const struct i2c_algorithm i2c_powermac_algorithm = { .smbus_xfer = i2c_powermac_smbus_xfer, .master_xfer = i2c_powermac_master_xfer, .functionality = i2c_powermac_func, }; static int i2c_powermac_remove(struct platform_device *dev) { struct i2c_adapter *adapter = platform_get_drvdata(dev); i2c_del_adapter(adapter); memset(adapter, 0, sizeof(*adapter)); return 0; } static u32 i2c_powermac_get_addr(struct i2c_adapter *adap, struct pmac_i2c_bus *bus, struct device_node *node) { const __be32 *prop; int len; /* First check for valid "reg" */ prop = of_get_property(node, "reg", &len); if (prop && (len >= sizeof(int))) return (be32_to_cpup(prop) & 0xff) >> 1; /* Then check old-style "i2c-address" */ prop = of_get_property(node, "i2c-address", &len); if (prop && (len >= sizeof(int))) return (be32_to_cpup(prop) & 0xff) >> 1; /* Now handle some devices with missing "reg" properties */ if (!strcmp(node->name, "cereal")) return 0x60; else if (!strcmp(node->name, "deq")) return 0x34; dev_warn(&adap->dev, "No i2c address for %s\n", node->full_name); return 0xffffffff; } static void i2c_powermac_create_one(struct i2c_adapter *adap, const char *type, u32 addr) { struct i2c_board_info info = {}; struct i2c_client *newdev; strncpy(info.type, type, sizeof(info.type)); info.addr = addr; newdev = i2c_new_device(adap, &info); if (!newdev) dev_err(&adap->dev, "i2c-powermac: Failure to register missing %s\n", type); } static void i2c_powermac_add_missing(struct i2c_adapter *adap, struct pmac_i2c_bus *bus, bool found_onyx) { struct device_node *busnode = pmac_i2c_get_bus_node(bus); int rc; /* Check for the onyx audio codec */ #define ONYX_REG_CONTROL 67 if (of_device_is_compatible(busnode, "k2-i2c") && !found_onyx) { union i2c_smbus_data data; rc = i2c_smbus_xfer(adap, 0x46, 0, I2C_SMBUS_READ, ONYX_REG_CONTROL, I2C_SMBUS_BYTE_DATA, &data); if (rc >= 0) i2c_powermac_create_one(adap, "MAC,pcm3052", 0x46); rc = i2c_smbus_xfer(adap, 0x47, 0, I2C_SMBUS_READ, ONYX_REG_CONTROL, I2C_SMBUS_BYTE_DATA, &data); if (rc >= 0) i2c_powermac_create_one(adap, "MAC,pcm3052", 0x47); } } static bool i2c_powermac_get_type(struct i2c_adapter *adap, struct device_node *node, u32 addr, char *type, int type_size) { char tmp[16]; /* Note: we to _NOT_ want the standard * i2c drivers to match with any of our powermac stuff * unless they have been specifically modified to handle * it on a case by case basis. For example, for thermal * control, things like lm75 etc... shall match with their * corresponding windfarm drivers, _NOT_ the generic ones, * so we force a prefix of AAPL, onto the modalias to * make that happen */ /* First try proper modalias */ if (of_modalias_node(node, tmp, sizeof(tmp)) >= 0) { snprintf(type, type_size, "MAC,%s", tmp); return true; } /* Now look for known workarounds */ if (!strcmp(node->name, "deq")) { /* Apple uses address 0x34 for TAS3001 and 0x35 for TAS3004 */ if (addr == 0x34) { snprintf(type, type_size, "MAC,tas3001"); return true; } else if (addr == 0x35) { snprintf(type, type_size, "MAC,tas3004"); return true; } } dev_err(&adap->dev, "i2c-powermac: modalias failure" " on %s\n", node->full_name); return false; } static void i2c_powermac_register_devices(struct i2c_adapter *adap, struct pmac_i2c_bus *bus) { struct i2c_client *newdev; struct device_node *node; bool found_onyx = 0; /* * In some cases we end up with the via-pmu node itself, in this * case we skip this function completely as the device-tree will * not contain anything useful. */ if (!strcmp(adap->dev.of_node->name, "via-pmu")) return; for_each_child_of_node(adap->dev.of_node, node) { struct i2c_board_info info = {}; u32 addr; /* Get address & channel */ addr = i2c_powermac_get_addr(adap, bus, node); if (addr == 0xffffffff) continue; /* Multibus setup, check channel */ if (!pmac_i2c_match_adapter(node, adap)) continue; dev_dbg(&adap->dev, "i2c-powermac: register %s\n", node->full_name); /* * Keep track of some device existence to handle * workarounds later. */ if (of_device_is_compatible(node, "pcm3052")) found_onyx = true; /* Make up a modalias */ if (!i2c_powermac_get_type(adap, node, addr, info.type, sizeof(info.type))) { continue; } /* Fill out the rest of the info structure */ info.addr = addr; info.irq = irq_of_parse_and_map(node, 0); info.of_node = of_node_get(node); newdev = i2c_new_device(adap, &info); if (!newdev) { dev_err(&adap->dev, "i2c-powermac: Failure to register" " %s\n", node->full_name); of_node_put(node); /* We do not dispose of the interrupt mapping on * purpose. It's not necessary (interrupt cannot be * re-used) and somebody else might have grabbed it * via direct DT lookup so let's not bother */ continue; } } /* Additional workarounds */ i2c_powermac_add_missing(adap, bus, found_onyx); } static int i2c_powermac_probe(struct platform_device *dev) { struct pmac_i2c_bus *bus = dev_get_platdata(&dev->dev); struct device_node *parent = NULL; struct i2c_adapter *adapter; const char *basename; int rc; if (bus == NULL) return -EINVAL; adapter = pmac_i2c_get_adapter(bus); /* Ok, now we need to make up a name for the interface that will * match what we used to do in the past, that is basically the * controller's parent device node for keywest. PMU didn't have a * naming convention and SMU has a different one */ switch(pmac_i2c_get_type(bus)) { case pmac_i2c_bus_keywest: parent = of_get_parent(pmac_i2c_get_controller(bus)); if (parent == NULL) return -EINVAL; basename = parent->name; break; case pmac_i2c_bus_pmu: basename = "pmu"; break; case pmac_i2c_bus_smu: /* This is not what we used to do but I'm fixing drivers at * the same time as this change */ basename = "smu"; break; default: return -EINVAL; } snprintf(adapter->name, sizeof(adapter->name), "%s %d", basename, pmac_i2c_get_channel(bus)); of_node_put(parent); platform_set_drvdata(dev, adapter); adapter->algo = &i2c_powermac_algorithm; i2c_set_adapdata(adapter, bus); adapter->dev.parent = &dev->dev; /* Clear of_node to skip automatic registration of i2c child nodes */ adapter->dev.of_node = NULL; rc = i2c_add_adapter(adapter); if (rc) { printk(KERN_ERR "i2c-powermac: Adapter %s registration " "failed\n", adapter->name); memset(adapter, 0, sizeof(*adapter)); return rc; } printk(KERN_INFO "PowerMac i2c bus %s registered\n", adapter->name); /* Use custom child registration due to Apple device-tree funkyness */ adapter->dev.of_node = dev->dev.of_node; i2c_powermac_register_devices(adapter, bus); return 0; } static struct platform_driver i2c_powermac_driver = { .probe = i2c_powermac_probe, .remove = i2c_powermac_remove, .driver = { .name = "i2c-powermac", .bus = &platform_bus_type, }, }; module_platform_driver(i2c_powermac_driver); MODULE_ALIAS("platform:i2c-powermac");