i2c: fsi: Prevent adding adapters for ports without dts nodes

Ports should be defined in the devicetree if they are to be enabled on
the system.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: fsi: Fix the port number field in status register

The port number field in the status register was not correct, so fix it.

Fixes: d6ffb6300116 ("i2c: Add FSI-attached I2C master algorithm")
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

i2c: fsi: Add of_put_node() before break

Each iteration of for_each_available_childe_of_node puts the previous
node, but in the case of a break from the middle of the loop, there
is no put, thus causing a memory leak. Add an of_node_put before the
break.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: fsi: Create busses for all ports

Currently we only create an I2C bus for the ports listed in the
device-tree for that master. There's no real reason for this since
we can discover the number of ports the master supports by looking
at the port_max field of the status register.

This patch re-works the bus add logic so that we always create buses
for each port, unless the bus is marked as unavailable in the DT. This
is useful since it ensures that all the buses provided by the CFAM I2C
master are accessible to debug tools.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: fsi: Add bus recovery

Bus recovery should reset the bus with the standard i2c recovery
procedure. Populate the necessary fields so that the standard procedure
can perform the reset.

Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: fsi: Add I2C master locking

Since there are many ports per master, each with it's own adapter and
chardev, we need some locking to prevent transfers from changing the
master state while other transfers are in progress.

Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: fsi: Add transfer implementation

Execute I2C transfers from the FSI-attached I2C master. Use polling
instead of interrupts as we have no hardware IRQ over FSI.

Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: fsi: Add abort and hardware reset procedures

Add abort procedure for failed transfers. Add engine reset procedure
that is executed during the abort to recover from various fault
conditions.

Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: fsi: Add port structures

Add and initialize I2C adapters for each port on the FSI-attached I2C
master. Ports for each master are defined in the devicetree.

Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

i2c: Add FSI-attached I2C master algorithm

Add register definitions for FSI-attached I2C master and functions to
access those registers over FSI. Add an FSI driver so that our I2C bus
is probed up during an FSI scan.

Signed-off-by: Eddie James <eajames@linux.vnet.ibm.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>