Commit Graph

7 Commits

Author SHA1 Message Date
Wolfram Sang be5b928038 i2c: reformat comments around i2c_smbus_xfer_emulated()
Use Kernel coding style for better readability.

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Reviewed-by: Peter Rosin <peda@axentia.se>
2018-02-27 13:54:05 +01:00
Linus Torvalds 4141cf676b Merge branch 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:
 "I2C has the following changes for you:

   - new flag to mark DMA safe buffers in i2c_msg. Also, some
     infrastructure around it. And docs.

   - huge refactoring of the at24 driver led by the new maintainer
     Bartosz

   - update I2C bus recovery to send STOP after recovery

   - conversion from gpio to gpiod for I2C bus recovery

   - adding a fault-injector to the i2c-gpio driver

   - lots of small driver improvements, and bigger ones to
     i2c-sh_mobile"

* 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (99 commits)
  i2c: mv64xxx: Add myself as maintainer for this driver
  i2c: mv64xxx: Fix clock resource by adding an optional bus clock
  i2c: mv64xxx: Remove useless test before clk_disable_unprepare
  i2c: mxs: use true and false for boolean values
  i2c: meson: update doc description to fix build warnings
  i2c: meson: add configurable divider factors
  dt-bindings: i2c: update documentation for the Meson-AXG
  i2c: imx-lpi2c: add runtime pm support
  i2c: rcar: fix some trivial typos in comments
  i2c: davinci: fix the cpufreq transition
  i2c: rk3x: add proper kerneldoc header
  i2c: rk3x: account for const type of of_device_id.data
  i2c: acorn: remove outdated path from file header
  i2c: acorn: add MODULE_LICENSE tag
  i2c: rcar: implement bus recovery
  i2c: send STOP after successful bus recovery
  i2c: ensure SDA is released in recovery if SDA is controllable
  i2c: add 'set_sda' to bus_recovery_info
  i2c: add identifier in declarations for i2c_bus_recovery
  i2c: make kerneldoc about bus recovery more precise
  ...
2018-02-04 10:57:43 -08:00
Jeremy Compostella 89c6efa61f i2c: core-smbus: prevent stack corruption on read I2C_BLOCK_DATA
On a I2C_SMBUS_I2C_BLOCK_DATA read request, if data->block[0] is
greater than I2C_SMBUS_BLOCK_MAX + 1, the underlying I2C driver writes
data out of the msgbuf1 array boundary.

It is possible from a user application to run into that issue by
calling the I2C_SMBUS ioctl with data.block[0] greater than
I2C_SMBUS_BLOCK_MAX + 1.

This patch makes the code compliant with
Documentation/i2c/dev-interface by raising an error when the requested
size is larger than 32 bytes.

Call Trace:
 [<ffffffff8139f695>] dump_stack+0x67/0x92
 [<ffffffff811802a4>] panic+0xc5/0x1eb
 [<ffffffff810ecb5f>] ? vprintk_default+0x1f/0x30
 [<ffffffff817456d3>] ? i2cdev_ioctl_smbus+0x303/0x320
 [<ffffffff8109a68b>] __stack_chk_fail+0x1b/0x20
 [<ffffffff817456d3>] i2cdev_ioctl_smbus+0x303/0x320
 [<ffffffff81745aed>] i2cdev_ioctl+0x4d/0x1e0
 [<ffffffff811f761a>] do_vfs_ioctl+0x2ba/0x490
 [<ffffffff81336e43>] ? security_file_ioctl+0x43/0x60
 [<ffffffff811f7869>] SyS_ioctl+0x79/0x90
 [<ffffffff81a22e97>] entry_SYSCALL_64_fastpath+0x12/0x6a

Signed-off-by: Jeremy Compostella <jeremy.compostella@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
2018-01-17 15:35:21 +01:00
Wolfram Sang 8a77821e74 i2c: smbus: use DMA safe buffers for emulated SMBus transactions
For all block commands, try to allocate a DMA safe buffer and mark it
accordingly. Only use the stack, if the buffers cannot be allocated.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03 21:24:52 +01:00
Phil Reid 69d17246ab i2c: i2c-smbus: add of_i2c_setup_smbus_alert
This commit adds of_i2c_setup_smbus_alert which allows the smbalert
driver to be attached to an i2c adapter via the device tree.

Signed-off-by: Phil Reid <preid@electromag.com.au>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-28 23:42:47 +02:00
Phil Reid 3c0a60bee1 i2c: i2c-smbus: Move i2c_setup_smbus_alert from i2c-smbus to i2c-core-smbus
In preparation to adding of_i2c_setup_smbus_alert() move
i2c_setup_smbus_alert() to core module. of_i2c_setup_smbus_alert()
will call i2c_setup_smbus_alert() and this avoid module dependecy issues.

Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-10-28 23:42:36 +02:00
Wolfram Sang 22c78d1cce i2c: break out smbus support into separate file
Break out the exported SMBus functions and the emulation layer into a
separate file. This also involved splitting up the tracing header into
an I2C and an SMBus part.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-05-31 21:01:03 +02:00