Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 1 | /* |
| 2 | i2c Support for Apple SMU Controller |
| 3 | |
| 4 | Copyright (c) 2005 Benjamin Herrenschmidt, IBM Corp. |
| 5 | <benh@kernel.crashing.org> |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 2 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program; if not, write to the Free Software |
| 19 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 20 | |
| 21 | */ |
| 22 | |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 23 | #include <linux/module.h> |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/types.h> |
| 26 | #include <linux/i2c.h> |
| 27 | #include <linux/init.h> |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 28 | #include <linux/device.h> |
| 29 | #include <linux/platform_device.h> |
| 30 | #include <asm/prom.h> |
| 31 | #include <asm/pmac_low_i2c.h> |
| 32 | |
| 33 | MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>"); |
| 34 | MODULE_DESCRIPTION("I2C driver for Apple PowerMac"); |
| 35 | MODULE_LICENSE("GPL"); |
| 36 | |
| 37 | /* |
| 38 | * SMBUS-type transfer entrypoint |
| 39 | */ |
| 40 | static s32 i2c_powermac_smbus_xfer( struct i2c_adapter* adap, |
| 41 | u16 addr, |
| 42 | unsigned short flags, |
| 43 | char read_write, |
| 44 | u8 command, |
| 45 | int size, |
| 46 | union i2c_smbus_data* data) |
| 47 | { |
| 48 | struct pmac_i2c_bus *bus = i2c_get_adapdata(adap); |
| 49 | int rc = 0; |
| 50 | int read = (read_write == I2C_SMBUS_READ); |
| 51 | int addrdir = (addr << 1) | read; |
| 52 | u8 local[2]; |
| 53 | |
| 54 | rc = pmac_i2c_open(bus, 0); |
| 55 | if (rc) |
| 56 | return rc; |
| 57 | |
| 58 | switch (size) { |
| 59 | case I2C_SMBUS_QUICK: |
| 60 | rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); |
| 61 | if (rc) |
| 62 | goto bail; |
| 63 | rc = pmac_i2c_xfer(bus, addrdir, 0, 0, NULL, 0); |
| 64 | break; |
| 65 | case I2C_SMBUS_BYTE: |
| 66 | rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); |
| 67 | if (rc) |
| 68 | goto bail; |
| 69 | rc = pmac_i2c_xfer(bus, addrdir, 0, 0, &data->byte, 1); |
| 70 | break; |
| 71 | case I2C_SMBUS_BYTE_DATA: |
| 72 | rc = pmac_i2c_setmode(bus, read ? |
| 73 | pmac_i2c_mode_combined : |
| 74 | pmac_i2c_mode_stdsub); |
| 75 | if (rc) |
| 76 | goto bail; |
| 77 | rc = pmac_i2c_xfer(bus, addrdir, 1, command, &data->byte, 1); |
| 78 | break; |
| 79 | case I2C_SMBUS_WORD_DATA: |
| 80 | rc = pmac_i2c_setmode(bus, read ? |
| 81 | pmac_i2c_mode_combined : |
| 82 | pmac_i2c_mode_stdsub); |
| 83 | if (rc) |
| 84 | goto bail; |
| 85 | if (!read) { |
| 86 | local[0] = data->word & 0xff; |
| 87 | local[1] = (data->word >> 8) & 0xff; |
| 88 | } |
| 89 | rc = pmac_i2c_xfer(bus, addrdir, 1, command, local, 2); |
| 90 | if (rc == 0 && read) { |
| 91 | data->word = ((u16)local[1]) << 8; |
| 92 | data->word |= local[0]; |
| 93 | } |
| 94 | break; |
| 95 | |
| 96 | /* Note that these are broken vs. the expected smbus API where |
Joe Perches | 96acafe | 2008-01-14 21:53:30 +0100 | [diff] [blame] | 97 | * on reads, the length is actually returned from the function, |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 98 | * but I think the current API makes no sense and I don't want |
| 99 | * any driver that I haven't verified for correctness to go |
| 100 | * anywhere near a pmac i2c bus anyway ... |
| 101 | * |
| 102 | * I'm also not completely sure what kind of phases to do between |
| 103 | * the actual command and the data (what I am _supposed_ to do that |
| 104 | * is). For now, I assume writes are a single stream and reads have |
| 105 | * a repeat start/addr phase (but not stop in between) |
| 106 | */ |
| 107 | case I2C_SMBUS_BLOCK_DATA: |
| 108 | rc = pmac_i2c_setmode(bus, read ? |
| 109 | pmac_i2c_mode_combined : |
| 110 | pmac_i2c_mode_stdsub); |
| 111 | if (rc) |
| 112 | goto bail; |
| 113 | rc = pmac_i2c_xfer(bus, addrdir, 1, command, data->block, |
| 114 | data->block[0] + 1); |
| 115 | |
| 116 | break; |
| 117 | case I2C_SMBUS_I2C_BLOCK_DATA: |
| 118 | rc = pmac_i2c_setmode(bus, read ? |
| 119 | pmac_i2c_mode_combined : |
| 120 | pmac_i2c_mode_stdsub); |
| 121 | if (rc) |
| 122 | goto bail; |
| 123 | rc = pmac_i2c_xfer(bus, addrdir, 1, command, |
Jean Delvare | 4b2643d | 2007-07-12 14:12:29 +0200 | [diff] [blame] | 124 | &data->block[1], data->block[0]); |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 125 | break; |
| 126 | |
| 127 | default: |
| 128 | rc = -EINVAL; |
| 129 | } |
| 130 | bail: |
| 131 | pmac_i2c_close(bus); |
| 132 | return rc; |
| 133 | } |
| 134 | |
| 135 | /* |
| 136 | * Generic i2c master transfer entrypoint. This driver only support single |
| 137 | * messages (for "lame i2c" transfers). Anything else should use the smbus |
| 138 | * entry point |
| 139 | */ |
| 140 | static int i2c_powermac_master_xfer( struct i2c_adapter *adap, |
| 141 | struct i2c_msg *msgs, |
| 142 | int num) |
| 143 | { |
| 144 | struct pmac_i2c_bus *bus = i2c_get_adapdata(adap); |
| 145 | int rc = 0; |
| 146 | int read; |
| 147 | int addrdir; |
| 148 | |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 149 | if (msgs->flags & I2C_M_TEN) |
| 150 | return -EINVAL; |
| 151 | read = (msgs->flags & I2C_M_RD) != 0; |
| 152 | addrdir = (msgs->addr << 1) | read; |
| 153 | if (msgs->flags & I2C_M_REV_DIR_ADDR) |
| 154 | addrdir ^= 1; |
| 155 | |
| 156 | rc = pmac_i2c_open(bus, 0); |
| 157 | if (rc) |
| 158 | return rc; |
| 159 | rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); |
| 160 | if (rc) |
| 161 | goto bail; |
| 162 | rc = pmac_i2c_xfer(bus, addrdir, 0, 0, msgs->buf, msgs->len); |
| 163 | bail: |
| 164 | pmac_i2c_close(bus); |
Jean Delvare | 8ced8ee | 2006-07-01 17:12:53 +0200 | [diff] [blame] | 165 | return rc < 0 ? rc : 1; |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 166 | } |
| 167 | |
| 168 | static u32 i2c_powermac_func(struct i2c_adapter * adapter) |
| 169 | { |
| 170 | return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | |
| 171 | I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | |
| 172 | I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_I2C; |
| 173 | } |
| 174 | |
| 175 | /* For now, we only handle smbus */ |
Jean Delvare | 8f9082c | 2006-09-03 22:39:46 +0200 | [diff] [blame] | 176 | static const struct i2c_algorithm i2c_powermac_algorithm = { |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 177 | .smbus_xfer = i2c_powermac_smbus_xfer, |
| 178 | .master_xfer = i2c_powermac_master_xfer, |
| 179 | .functionality = i2c_powermac_func, |
| 180 | }; |
| 181 | |
| 182 | |
Uwe Kleine-Koenig | 4ebb52d | 2008-09-24 13:39:21 +0200 | [diff] [blame] | 183 | static int __devexit i2c_powermac_remove(struct platform_device *dev) |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 184 | { |
Benjamin Herrenschmidt | 9f2545c | 2006-10-10 11:45:45 +1000 | [diff] [blame] | 185 | struct i2c_adapter *adapter = platform_get_drvdata(dev); |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 186 | struct pmac_i2c_bus *bus = i2c_get_adapdata(adapter); |
| 187 | int rc; |
| 188 | |
| 189 | rc = i2c_del_adapter(adapter); |
| 190 | pmac_i2c_detach_adapter(bus, adapter); |
| 191 | i2c_set_adapdata(adapter, NULL); |
| 192 | /* We aren't that prepared to deal with this... */ |
| 193 | if (rc) |
| 194 | printk("i2c-powermac.c: Failed to remove bus %s !\n", |
| 195 | adapter->name); |
Benjamin Herrenschmidt | 9f2545c | 2006-10-10 11:45:45 +1000 | [diff] [blame] | 196 | platform_set_drvdata(dev, NULL); |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 197 | kfree(adapter); |
| 198 | |
| 199 | return 0; |
| 200 | } |
| 201 | |
| 202 | |
Uwe Kleine-Koenig | 4ebb52d | 2008-09-24 13:39:21 +0200 | [diff] [blame] | 203 | static int __devinit i2c_powermac_probe(struct platform_device *dev) |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 204 | { |
Benjamin Herrenschmidt | 9f2545c | 2006-10-10 11:45:45 +1000 | [diff] [blame] | 205 | struct pmac_i2c_bus *bus = dev->dev.platform_data; |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 206 | struct device_node *parent = NULL; |
| 207 | struct i2c_adapter *adapter; |
Jeremy Kerr | 018a3d1 | 2006-07-12 15:40:29 +1000 | [diff] [blame] | 208 | char name[32]; |
| 209 | const char *basename; |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 210 | int rc; |
| 211 | |
| 212 | if (bus == NULL) |
| 213 | return -EINVAL; |
| 214 | |
| 215 | /* Ok, now we need to make up a name for the interface that will |
| 216 | * match what we used to do in the past, that is basically the |
| 217 | * controller's parent device node for keywest. PMU didn't have a |
| 218 | * naming convention and SMU has a different one |
| 219 | */ |
| 220 | switch(pmac_i2c_get_type(bus)) { |
| 221 | case pmac_i2c_bus_keywest: |
| 222 | parent = of_get_parent(pmac_i2c_get_controller(bus)); |
| 223 | if (parent == NULL) |
| 224 | return -EINVAL; |
| 225 | basename = parent->name; |
| 226 | break; |
| 227 | case pmac_i2c_bus_pmu: |
| 228 | basename = "pmu"; |
| 229 | break; |
| 230 | case pmac_i2c_bus_smu: |
| 231 | /* This is not what we used to do but I'm fixing drivers at |
| 232 | * the same time as this change |
| 233 | */ |
| 234 | basename = "smu"; |
| 235 | break; |
| 236 | default: |
| 237 | return -EINVAL; |
| 238 | } |
| 239 | snprintf(name, 32, "%s %d", basename, pmac_i2c_get_channel(bus)); |
| 240 | of_node_put(parent); |
| 241 | |
| 242 | adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL); |
| 243 | if (adapter == NULL) { |
| 244 | printk(KERN_ERR "i2c-powermac: can't allocate inteface !\n"); |
| 245 | return -ENOMEM; |
| 246 | } |
Benjamin Herrenschmidt | 9f2545c | 2006-10-10 11:45:45 +1000 | [diff] [blame] | 247 | platform_set_drvdata(dev, adapter); |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 248 | strcpy(adapter->name, name); |
| 249 | adapter->algo = &i2c_powermac_algorithm; |
| 250 | i2c_set_adapdata(adapter, bus); |
Benjamin Herrenschmidt | 9f2545c | 2006-10-10 11:45:45 +1000 | [diff] [blame] | 251 | adapter->dev.parent = &dev->dev; |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 252 | pmac_i2c_attach_adapter(bus, adapter); |
| 253 | rc = i2c_add_adapter(adapter); |
| 254 | if (rc) { |
| 255 | printk(KERN_ERR "i2c-powermac: Adapter %s registration " |
| 256 | "failed\n", name); |
| 257 | i2c_set_adapdata(adapter, NULL); |
| 258 | pmac_i2c_detach_adapter(bus, adapter); |
| 259 | } |
| 260 | |
| 261 | printk(KERN_INFO "PowerMac i2c bus %s registered\n", name); |
| 262 | return rc; |
| 263 | } |
| 264 | |
| 265 | |
Kay Sievers | add8eda | 2008-04-22 22:16:49 +0200 | [diff] [blame] | 266 | /* work with hotplug and coldplug */ |
| 267 | MODULE_ALIAS("platform:i2c-powermac"); |
| 268 | |
Benjamin Herrenschmidt | 9f2545c | 2006-10-10 11:45:45 +1000 | [diff] [blame] | 269 | static struct platform_driver i2c_powermac_driver = { |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 270 | .probe = i2c_powermac_probe, |
Benjamin Herrenschmidt | 9f2545c | 2006-10-10 11:45:45 +1000 | [diff] [blame] | 271 | .remove = __devexit_p(i2c_powermac_remove), |
| 272 | .driver = { |
| 273 | .name = "i2c-powermac", |
| 274 | .bus = &platform_bus_type, |
| 275 | }, |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 276 | }; |
| 277 | |
| 278 | static int __init i2c_powermac_init(void) |
| 279 | { |
Benjamin Herrenschmidt | 9f2545c | 2006-10-10 11:45:45 +1000 | [diff] [blame] | 280 | platform_driver_register(&i2c_powermac_driver); |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 281 | return 0; |
| 282 | } |
| 283 | |
| 284 | |
| 285 | static void __exit i2c_powermac_cleanup(void) |
| 286 | { |
Benjamin Herrenschmidt | 9f2545c | 2006-10-10 11:45:45 +1000 | [diff] [blame] | 287 | platform_driver_unregister(&i2c_powermac_driver); |
Benjamin Herrenschmidt | a28d3af | 2006-01-07 11:35:26 +1100 | [diff] [blame] | 288 | } |
| 289 | |
| 290 | module_init(i2c_powermac_init); |
| 291 | module_exit(i2c_powermac_cleanup); |