| /* | 
 |     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/init.h> | 
 | #include <linux/device.h> | 
 | #include <linux/platform_device.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; | 
 | 	u8			local[2]; | 
 |  | 
 | 	rc = pmac_i2c_open(bus, 0); | 
 | 	if (rc) | 
 | 		return rc; | 
 |  | 
 | 	switch (size) { | 
 |         case I2C_SMBUS_QUICK: | 
 | 		rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); | 
 | 		if (rc) | 
 | 			goto bail; | 
 | 		rc = pmac_i2c_xfer(bus, addrdir, 0, 0, NULL, 0); | 
 | 	    	break; | 
 |         case I2C_SMBUS_BYTE: | 
 | 		rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); | 
 | 		if (rc) | 
 | 			goto bail; | 
 | 		rc = pmac_i2c_xfer(bus, addrdir, 0, 0, &data->byte, 1); | 
 | 	    	break; | 
 |         case I2C_SMBUS_BYTE_DATA: | 
 | 		rc = pmac_i2c_setmode(bus, read ? | 
 | 				      pmac_i2c_mode_combined : | 
 | 				      pmac_i2c_mode_stdsub); | 
 | 		if (rc) | 
 | 			goto bail; | 
 | 		rc = pmac_i2c_xfer(bus, addrdir, 1, command, &data->byte, 1); | 
 | 	    	break; | 
 |         case I2C_SMBUS_WORD_DATA: | 
 | 		rc = pmac_i2c_setmode(bus, read ? | 
 | 				      pmac_i2c_mode_combined : | 
 | 				      pmac_i2c_mode_stdsub); | 
 | 		if (rc) | 
 | 			goto bail; | 
 | 		if (!read) { | 
 | 			local[0] = data->word & 0xff; | 
 | 			local[1] = (data->word >> 8) & 0xff; | 
 | 		} | 
 | 		rc = pmac_i2c_xfer(bus, addrdir, 1, command, local, 2); | 
 | 		if (rc == 0 && read) { | 
 | 			data->word = ((u16)local[1]) << 8; | 
 | 			data->word |= local[0]; | 
 | 		} | 
 | 	    	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: | 
 | 		rc = pmac_i2c_setmode(bus, read ? | 
 | 				      pmac_i2c_mode_combined : | 
 | 				      pmac_i2c_mode_stdsub); | 
 | 		if (rc) | 
 | 			goto bail; | 
 | 		rc = pmac_i2c_xfer(bus, addrdir, 1, command, data->block, | 
 | 				   data->block[0] + 1); | 
 |  | 
 | 		break; | 
 | 	case I2C_SMBUS_I2C_BLOCK_DATA: | 
 | 		rc = pmac_i2c_setmode(bus, read ? | 
 | 				      pmac_i2c_mode_combined : | 
 | 				      pmac_i2c_mode_stdsub); | 
 | 		if (rc) | 
 | 			goto bail; | 
 | 		rc = pmac_i2c_xfer(bus, addrdir, 1, command, | 
 | 				   &data->block[1], data->block[0]); | 
 | 		break; | 
 |  | 
 |         default: | 
 | 	    	rc = -EINVAL; | 
 | 	} | 
 |  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 (msgs->flags & I2C_M_TEN) | 
 | 		return -EINVAL; | 
 | 	read = (msgs->flags & I2C_M_RD) != 0; | 
 | 	addrdir = (msgs->addr << 1) | read; | 
 | 	if (msgs->flags & I2C_M_REV_DIR_ADDR) | 
 | 		addrdir ^= 1; | 
 |  | 
 | 	rc = pmac_i2c_open(bus, 0); | 
 | 	if (rc) | 
 | 		return rc; | 
 | 	rc = pmac_i2c_setmode(bus, pmac_i2c_mode_std); | 
 | 	if (rc) | 
 | 		goto bail; | 
 | 	rc = pmac_i2c_xfer(bus, addrdir, 0, 0, msgs->buf, msgs->len); | 
 |  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 __devexit i2c_powermac_remove(struct platform_device *dev) | 
 | { | 
 | 	struct i2c_adapter	*adapter = platform_get_drvdata(dev); | 
 | 	struct pmac_i2c_bus	*bus = i2c_get_adapdata(adapter); | 
 | 	int			rc; | 
 |  | 
 | 	rc = i2c_del_adapter(adapter); | 
 | 	pmac_i2c_detach_adapter(bus, adapter); | 
 | 	i2c_set_adapdata(adapter, NULL); | 
 | 	/* We aren't that prepared to deal with this... */ | 
 | 	if (rc) | 
 | 		printk("i2c-powermac.c: Failed to remove bus %s !\n", | 
 | 		       adapter->name); | 
 | 	platform_set_drvdata(dev, NULL); | 
 | 	kfree(adapter); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 |  | 
 | static int __devinit i2c_powermac_probe(struct platform_device *dev) | 
 | { | 
 | 	struct pmac_i2c_bus *bus = dev->dev.platform_data; | 
 | 	struct device_node *parent = NULL; | 
 | 	struct i2c_adapter *adapter; | 
 | 	char name[32]; | 
 | 	const char *basename; | 
 | 	int rc; | 
 |  | 
 | 	if (bus == NULL) | 
 | 		return -EINVAL; | 
 |  | 
 | 	/* 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(name, 32, "%s %d", basename, pmac_i2c_get_channel(bus)); | 
 | 	of_node_put(parent); | 
 |  | 
 | 	adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL); | 
 | 	if (adapter == NULL) { | 
 | 		printk(KERN_ERR "i2c-powermac: can't allocate inteface !\n"); | 
 | 		return -ENOMEM; | 
 | 	} | 
 | 	platform_set_drvdata(dev, adapter); | 
 | 	strcpy(adapter->name, name); | 
 | 	adapter->algo = &i2c_powermac_algorithm; | 
 | 	i2c_set_adapdata(adapter, bus); | 
 | 	adapter->dev.parent = &dev->dev; | 
 | 	pmac_i2c_attach_adapter(bus, adapter); | 
 | 	rc = i2c_add_adapter(adapter); | 
 | 	if (rc) { | 
 | 		printk(KERN_ERR "i2c-powermac: Adapter %s registration " | 
 | 		       "failed\n", name); | 
 | 		i2c_set_adapdata(adapter, NULL); | 
 | 		pmac_i2c_detach_adapter(bus, adapter); | 
 | 	} | 
 |  | 
 | 	printk(KERN_INFO "PowerMac i2c bus %s registered\n", name); | 
 |  | 
 | 	if (!strncmp(basename, "uni-n", 5)) { | 
 | 		struct device_node *np; | 
 | 		const u32 *prop; | 
 | 		struct i2c_board_info info; | 
 |  | 
 | 		/* Instantiate I2C motion sensor if present */ | 
 | 		np = of_find_node_by_name(NULL, "accelerometer"); | 
 | 		if (np && of_device_is_compatible(np, "AAPL,accelerometer_1") && | 
 | 		    (prop = of_get_property(np, "reg", NULL))) { | 
 | 			int i2c_bus; | 
 | 			const char *tmp_bus; | 
 |  | 
 | 			/* look for bus either using "reg" or by path */ | 
 | 			tmp_bus = strstr(np->full_name, "/i2c-bus@"); | 
 | 			if (tmp_bus) | 
 | 				i2c_bus = *(tmp_bus + 9) - '0'; | 
 | 			else | 
 | 				i2c_bus = ((*prop) >> 8) & 0x0f; | 
 |  | 
 | 			if (pmac_i2c_get_channel(bus) == i2c_bus) { | 
 | 				memset(&info, 0, sizeof(struct i2c_board_info)); | 
 | 				info.addr = ((*prop) & 0xff) >> 1; | 
 | 				strlcpy(info.type, "ams", I2C_NAME_SIZE); | 
 | 				i2c_new_device(adapter, &info); | 
 | 			} | 
 | 		} | 
 | 	} | 
 |  | 
 | 	return rc; | 
 | } | 
 |  | 
 |  | 
 | /* work with hotplug and coldplug */ | 
 | MODULE_ALIAS("platform:i2c-powermac"); | 
 |  | 
 | static struct platform_driver i2c_powermac_driver = { | 
 | 	.probe = i2c_powermac_probe, | 
 | 	.remove = __devexit_p(i2c_powermac_remove), | 
 | 	.driver = { | 
 | 		.name = "i2c-powermac", | 
 | 		.bus = &platform_bus_type, | 
 | 	}, | 
 | }; | 
 |  | 
 | static int __init i2c_powermac_init(void) | 
 | { | 
 | 	platform_driver_register(&i2c_powermac_driver); | 
 | 	return 0; | 
 | } | 
 |  | 
 |  | 
 | static void __exit i2c_powermac_cleanup(void) | 
 | { | 
 | 	platform_driver_unregister(&i2c_powermac_driver); | 
 | } | 
 |  | 
 | module_init(i2c_powermac_init); | 
 | module_exit(i2c_powermac_cleanup); |