aboutsummaryrefslogtreecommitdiff
path: root/drivers/i2c/chips/max6875.c
AgeCommit message (Collapse)Author
2008-01-27i2c: normal_i2c can be made const (remaining drivers)Jean Delvare
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-07-12Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6Linus Torvalds
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/driver-2.6: (61 commits) sysfs: add parameter "struct bin_attribute *" in .read/.write methods for sysfs binary attributes sysfs: make directory dentries and inodes reclaimable sysfs: implement sysfs_get_dentry() sysfs: move sysfs_drop_dentry() to dir.c and make it static sysfs: restructure add/remove paths and fix inode update sysfs: use sysfs_mutex to protect the sysfs_dirent tree sysfs: consolidate sysfs spinlocks sysfs: make kobj point to sysfs_dirent instead of dentry sysfs: implement sysfs_find_dirent() and sysfs_get_dirent() sysfs: implement SYSFS_FLAG_REMOVED flag sysfs: rename sysfs_dirent->s_type to s_flags and make room for flags sysfs: make sysfs_drop_dentry() access inodes using ilookup() sysfs: Fix oops in sysfs_drop_dentry on x86_64 sysfs: use singly-linked list for sysfs_dirent tree sysfs: slim down sysfs_dirent->s_active sysfs: move s_active functions to fs/sysfs/dir.c sysfs: fix root sysfs_dirent -> root dentry association sysfs: use iget_locked() instead of new_inode() sysfs: reorganize sysfs_new_indoe() and sysfs_create() sysfs: fix parent refcounting during rename and move ...
2007-07-12i2c: Fix the i2c_smbus_read_i2c_block_data() prototypeJean Delvare
Let the drivers specify how many bytes they want to read with i2c_smbus_read_i2c_block_data(). So far, the block count was hard-coded to I2C_SMBUS_BLOCK_MAX (32), which did not make much sense. Many driver authors complained about this before, and I believe it's about time to fix it. Right now, authors have to do technically stupid things, such as individual byte reads or full-fledged I2C messaging, to work around the problem. We do not want to encourage that. I even found that some bus drivers (e.g. i2c-amd8111) already implemented I2C block read the "right" way, that is, they didn't follow the old, broken standard. The fact that it was never noticed before just shows how little i2c_smbus_read_i2c_block_data() was used, which isn't that surprising given how broken its prototype was so far. There are some obvious compatiblity considerations: * This changes the i2c_smbus_read_i2c_block_data() prototype. Users outside the kernel tree will notice at compilation time, and will have to update their code. * User-space has access to i2c_smbus_xfer() directly using i2c-dev, so the changed expectations would affect tools such as i2cdump. In order to preserve binary compatibility, we give I2C_SMBUS_I2C_BLOCK_DATA a new numeric value, and define I2C_SMBUS_I2C_BLOCK_BROKEN with the old numeric value. When i2c-dev receives a transaction with the old value, it can convert it to the new format on the fly. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-07-11sysfs: add parameter "struct bin_attribute *" in .read/.write methods for ↵Zhang Rui
sysfs binary attributes Well, first of all, I don't want to change so many files either. What I do: Adding a new parameter "struct bin_attribute *" in the .read/.write methods for the sysfs binary attributes. In fact, only the four lines change in fs/sysfs/bin.c and include/linux/sysfs.h do the real work. But I have to update all the files that use binary attributes to make them compatible with the new .read and .write methods. I'm not sure if I missed any. :( Why I do this: For a sysfs attribute, we can get a pointer pointing to the struct attribute in the .show/.store method, while we can't do this for the binary attributes. I don't know why this is different, but this does make it not so handy to use the binary attributes as the regular ones. So I think this patch is reasonable. :) Who benefits from it: The patch that exposes ACPI tables in sysfs requires such an improvement. All the table binary attributes share the same .read method. Parameter "struct bin_attribute *" is used to get the table signature and instance number which are used to distinguish different ACPI table binary attributes. Without this parameter, we need to offer different .read methods for different ACPI table binary attributes. This is impossible as there are various ACPI tables on different platforms, and we don't know what they are until they are loaded. Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2007-07-11sysfs: kill unnecessary attribute->ownerTejun Heo
sysfs is now completely out of driver/module lifetime game. After deletion, a sysfs node doesn't access anything outside sysfs proper, so there's no reason to hold onto the attribute owners. Note that often the wrong modules were accounted for as owners leading to accessing removed modules. This patch kills now unnecessary attribute->owner. Note that with this change, userland holding a sysfs node does not prevent the backing module from being unloaded. For more info regarding lifetime rule cleanup, please read the following message. http://article.gmane.org/gmane.linux.kernel/510293 (tweaked by Greg to not delete the field just yet, to make it easier to merge things properly.) Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-09-26i2c: __must_check fixes (chip drivers)Jean Delvare
i2c: __must_check fixes (chip drivers) Check for error on sysfs file creation. Delete sysfs files on device removal. The approach taken for the most complex case (pcf8591) is similar to what Mark M. Hoffman proposed for hardware monitoring chip drivers. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Ben Gardner <bgardner@wabtec.com> Cc: Aurelien Jarno <aurelien@aurel32.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-03-23[PATCH] i2c: Semaphore to mutex conversions, part 2Ingo Molnar
semaphore to mutex conversion. the conversion was generated via scripts, and the result was validated automatically via a script as well. build tested. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-05[PATCH] I2C: Remove .owner setting from i2c_driver as it's no longer neededGreg Kroah-Hartman
Now that i2c_add_driver() doesn't need the module owner to be set by hand, we can delete it from the drivers. This patch catches all of the drivers that I found in the current tree (if a driver sets the .owner by hand, it's not a problem, just not needed.) Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Cc: Jean Delvare <khali@linux-fr.org>
2006-01-05[PATCH] i2c: Drop i2c_driver.{owner,name}, 2 of 11Laurent Riffard
We should use the i2c_driver.driver's .name and .owner fields instead of the i2c_driver's ones. This patch updates the miscellaneaous i2c chip drivers. Signed-off-by: Laurent Riffard <laurent.riffard@free.fr> Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-05[PATCH] i2c: Drop i2c_driver.flags, 2 of 3Jean Delvare
Just about every i2c chip driver sets the I2C_DF_NOTIFY flag, so we can simply make it the default and drop the flag. If any driver really doesn't want to be notified when i2c adapters are added, that driver can simply omit to set .attach_adapter. This approach is also more robust as it prevents accidental NULL pointer dereferences. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-28[PATCH] i2c: kzalloc conversion, other driversDeepak Saxena
Use kzalloc instead of kmalloc+memset in all remaining i2c bus and chip drivers. Signed-off-by: Deepak Saxena <dsaxena@plexity.net> Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] I2C: Centralize 24RF08 corruption preventionJean Delvare
The 24RF08 corruption would better be prevented at i2c-core level than at chip driver level, for several reasons: * The second quick write should happen as soon as possible after the first one, so as to limit the risk that another command is issued on the bus inbetween, causing the corruption. * As a matter of fact, the protection code at driver level was reworked at least three times already, which proves how hard it is to get it right there, while it's straightforward at i2c-core level. * It's easy to add a new driver that would need the protection, and forget to add it. This did happen already. * As additional probing addresses can be passed to most i2c chip drivers as module parameters, virtually every i2c chip driver would need the protection if we want to be really safe. * Why duplicate code when we can easily avoid it? Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] hwmon: hwmon vs i2c, second round (06/11)Jean Delvare
The only thing left in i2c-sensor.h are module parameter definition macros. It's only an extension of what i2c.h offers, and this extension is not sensors-specific. As a matter of fact, a few non-sensors drivers use them. So we better merge them in i2c.h, and get rid of i2c-sensor.h altogether. Signed-off-by: Jean Delvare <khali@linux-fr> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] hwmon: hwmon vs i2c, second round (04/11)Jean Delvare
i2c_probe and i2c_detect now do the exact same thing and operate on the same data structure, so we can have everyone call i2c_probe. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] I2C: refactor message in i2c_detach_clientJean Delvare
We could refactor the error message 34 different i2c drivers print if i2c_detach_client() fails in this function itself. Saves quite a few lines of code. Documentation is updated to reflect that change. Note that this patch should be applied after Rudolf Marek's w83792d patches. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] I2C: Separate non-i2c hwmon drivers from i2c-core (7/9)Jean Delvare
Kill normal_isa in header files, documentation and all chip drivers, as it is no more used. normal_i2c could be renamed to normal, but I decided not to do so at the moment, so as to limit the number of changes. This might be done later as part of the i2c_probe/i2c_detect merge. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] I2C: max6875 code cleanupbgardner@wabtec.com
Remove an unused local variable and change the subclient name. Signed-off-by: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] I2C: add kobj_to_i2c_clientbgardner@wabtec.com
Move the inline function kobj_to_i2c_client() from max6875.c to i2c.h. Signed-off-by: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] I2C: fix max6875 build errorGreg Kroah-Hartman
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-09-05[PATCH] I2C: simplify max6875 driverbgardner@wabtec.com
This is an update to the max6875 driver. It no longer does any detection, so the address must be forced on module load. It only makes available the user EEPROM (read-only). This patch is based off 2.6.13-rc2-mm2. Signed-off-by: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-07-29[PATCH] I2C: 24RF08 corruption prevention (again)Jean Delvare
The 24RF08 corruption prevention in the eeprom and max6875 drivers wasn't complete. For one thing, the additional quick write should happen as soon as possible and unconditionally, while both drivers had error paths before. For another, when a given chip is forced, the core does not emit a quick write, so a second quick write would cause the corruption rather than prevent it. I plan to move the corruption prevention in the core in the long run, so that individual drivers don't have to care anymore. But I need to merge i2c_probe and i2c_detect before I do (work in progress). Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-11[PATCH] I2C: New max6875 driver may corrupt EEPROMsJean Delvare
After a careful code analysis on the new max6875 driver (drivers/i2c/chips/max6875.c), I have come to the conclusion that this driver may cause EEPROM corruptions if used on random systems. The EEPROM part of the MAX6875 chip is accessed using rather uncommon I2C sequences. What is seen by the MAX6875 as reads can be seen by a standard EEPROM (24C02) as writes. If you check the detection method used by the driver, you'll find that the first SMBus command it will send on the bus is i2c_smbus_write_byte_data(client, 0x80, 0x40). For the MAX6875 it makes an internal pointer point to a specific offset of the EEPROM waiting for a subsequent read command, so it's not an actual data write operation, but for a standard EEPROM, this instead means writing value 0x40 to offset 0x80. Blame Philips and Intel for the obscure protocol. Since the MAX6875 and the standard, common 24C02 EEPROMs share two I2C addresses (0x50 and 0x52), loading the max6875 driver on a system with standard EEPROMs at either address will trigger a write on these EEPROMs, which will lead to their corruption if they happen not to be write protected. This kind of EEPROMs can be found on memory modules (SPD), ethernet adapters (MAC address), laptops (proprietary data) and displays (EDID/DDC). Most of these are hopefully write-protected, but not all of them. For this reason, I would recommend that the max6875 driver be neutralized, in a way that nobody can corrupt his/her EEPROMs by just loading the driver. This means either deleting the driver completely, or not listing any default address for it. I'd like this to be done before 2.6.13-rc1 is released. Additionally, the max6875 driver lacks the 24RF08 corruption preventer present in the eeprom driver, which means that loading this driver in a system with such a chip would corrupt it as well. Here is a proposed quick patch addressing the issue, although I wouldn't mind a complete removal if it makes everyone feel safer. I think Ben has plans to replace this driver by a much simplified one anyway. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-21[PATCH] max6875: new i2c device driverBGardner@Wabtec.com
This patch adds support for the MAX6875/MAX6874 chips. Signed-off-by: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>