i2cdetect -q was broken (everything was a false positive, and no transfers were
actually being sent over i2c). The way it works is by sending a 0 length write
request and checking for NACK. This patch fixes the 0 length writes and actually
sends them.
Reported-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NAlexandru M Stan <amstan@chromium.org>
Tested-by: NDoug Anderson <dianders@chromium.org>
Tested-by: NMax Schwarz <max.schwarz@online.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

I2C_CLKDIV register descripted in the previous version of
RK3x chip manual is incorrect. Plus 1 is required.

The correct formula:
- T(SCL_HIGH) = T(PCLK) * (CLKDIVH + 1) * 8
- T(SCL_LOW) = T(PCLK) * (CLKDIVL + 1) * 8
- (SCL Divsor) = 8 * ((CLKDIVL + 1) + (CLKDIVH + 1))
- SCL = PCLK / (CLK Divsor)

It will be updated to the latest version of chip manual.
Signed-off-by: NAddy Ke <addy.ke@rock-chips.com>
Reviewed-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

In rk3x SOC, the I2C controller can receive/transmit up to 32 bytes data
in one chunk, so the size of data to be write/read to/from TXDATAx/RXDATAx
must be less than or equal 32 bytes at a time.

Tested on rk3288-pinky board, elan receive 158 bytes data.
Signed-off-by: NAddy Ke <addy.ke@rock-chips.com>
Acked-by: NMax Schwarz <max.schwarz@online.de>
Reviewed-by: NDoug Anderson <dianders@chromium.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

If slave holds scl, I2C_IPD[7] will be set 1 by controller
for debugging. Driver must ignore it.

[    5.752391] rk3x-i2c ff160000.i2c: unexpected irq in WRITE: 0x80
[    5.939027] rk3x-i2c ff160000.i2c: timeout, ipd: 0x80, state: 4
Signed-off-by: NAddy Ke <addy.ke@rock-chips.com>
Reviewed-by: NHeiko Stuebner <heiko@sntech.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org

drivers/i2c/busses/i2c-rk3x.c:610:69-70: rk3x_i2c_match is not NULL terminated at line 610

Make sure of_device_id tables are NULL terminated
Generated by: /kbuild/src/linux/scripts/coccinelle/misc/of_table.cocci
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

Driver for the native I2C adapter found in Rockchip RK3xxx SoCs.

Configuration is only possible through devicetree. The driver is
interrupt driven and supports the I2C_M_IGNORE_NAK mangling bit.
Signed-off-by: NMax Schwarz <max.schwarz@online.de>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>