Commit Graph

6 Commits

Author SHA1 Message Date
Linus Torvalds d2d8f51e28 Merge branch 'i2c/for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux
Pull i2c updates from Wolfram Sang:

 - new drivers for Spreadtrum I2C, Intel Cherry Trail Whiskey Cove SMBUS

 - quite some driver updates

 - cleanups for the i2c-mux subsystem

 - some subsystem-wide constification

 - further cleanup of include/linux/i2c

* 'i2c/for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (50 commits)
  i2c: sprd: Fix undefined reference errors
  i2c: nomadik: constify amba_id
  i2c: versatile: Make i2c_algo_bit_data const
  i2c: busses: make i2c_adapter_quirks const
  i2c: busses: make i2c_adapter const
  i2c: busses: make i2c_algorithm const
  i2c: Add Spreadtrum I2C controller driver
  dt-bindings: i2c: Add Spreadtrum I2C controller documentation
  i2c-cht-wc: make cht_wc_i2c_adap_driver static
  MAINTAINERS: Add entry for drivers/i2c/busses/i2c-cht-wc.c
  i2c: aspeed: Retain delay/setup/hold values when configuring bus frequency
  dt-bindings: i2c: eeprom: Document vendor to be used and deprecated ones
  i2c: i801: Restore the presence state of P2SB PCI device after reading BAR
  MAINTAINERS: drop entry for Blackfin I2C and Sonic's email
  blackfin: merge the two TWI header files
  i2c: davinci: Preserve return value of devm_clk_get
  i2c: mediatek: Add i2c compatible for MediaTek MT7622
  dt-bindings: i2c: Add MediaTek MT7622 i2c binding
  dt-bindings: i2c: modify information formats
  i2c: mux: i2c-arb-gpio-challenge: allow compiling w/o OF support
  ...
2017-09-09 14:18:40 -07:00
Andrew Jeffery 95fd3ad9cd i2c: aspeed: Retain delay/setup/hold values when configuring bus frequency
In addition to the base, low and high clock configuration, the AC timing
register #1 on the AST2400 houses fields controlling:

1. tBUF: Minimum delay between Stop and Start conditions
2. tHDSTA: Hold time for the Start condition
3. tACST: Setup time for Start and Stop conditions, and hold time for the
   Repeated Start condition

These values are defined in hardware on the AST2500 and therefore don't
need to be set.

aspeed_i2c_init_clk() was performing a direct write of the generated
clock values rather than a read/mask/modify/update sequence to retain
tBUF, tHDSTA and tACST, and therefore cleared the tBUF, tHDSTA and tACST
fields on the AST2400. This resulted in a delay/setup/hold time of 1
base clock, which in some configurations is not enough for some devices
(e.g. the MAX31785 fan controller, with an APB of 48MHz and a desired
bus speed of 100kHz).

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Tested-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-08-28 18:05:03 +02:00
Brendan Higgins f1c0b7e448 i2c: aspeed: fixed potential null pointer dereference
Before I skipped null checks when the master is in the STOP state; this
fixes that.

Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: f327c686d3 ("i2c: aspeed: added driver for Aspeed I2C")
2017-08-14 22:08:13 +02:00
Brendan Higgins 87b59ff8d1 i2c: aspeed: add proper support fo 24xx clock params
24xx BMCs have larger clock divider granularity which can cause problems
when trying to set them as 25xx clock dividers; this adds clock setting
code specific to 24xx.

This also fixes a potential issue where clock dividers were rounded down
instead of up.

Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-08-14 22:05:56 +02:00
Brendan Higgins f9eb91350b i2c: aspeed: added slave support for Aspeed I2C driver
Added slave support for Aspeed I2C controller. Supports fourteen busses
present in AST24XX and AST25XX BMC SoCs by Aspeed.

Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-23 20:39:38 +02:00
Brendan Higgins f327c686d3 i2c: aspeed: added driver for Aspeed I2C
Added initial master support for Aspeed I2C controller. Supports
fourteen busses present in AST24XX and AST25XX BMC SoCs by Aspeed.

Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-23 20:39:18 +02:00