The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://lore.kernel.org/linux-i3c/20200227131307.GA24935@embeddedor
For today the reattach function only update the device address on the
controller.
Update the location to the first available too, will optimize the
enumeration process avoiding additional checks to keep the available
positions on address table consecutive.
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
i3c_bus_set_mode function is only used in master.c.
Make it static to avoid warning when compiling with W=1.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
This patch adds support for THD_DEL (Data Hold Delay) to Cadence
I3C master constoller driver.
As per MIPI I3C Specification 1.0, Table 75 (page 142) defines
non-zero minimal tHD_PP timing on master output (Fig 65). This
setting allows to meet this timing on master's soc outputs,
regardless of PCB balancing.
Signed-off-by: Przemyslaw Gaj <pgaj@cadence.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
In i3c_master_getmwl_locked(), the buffer used for the dest payload data is
allocated using kzalloc() in i3c_ccc_cmd_dest_init(). Later on, the length
of the dest payload data is checked against 'sizeof(*mwl)'. If they are not
equal, -EIO is returned to indicate the error. However, the allocated
buffer is not deallocated on this path, leading to a memory leak.
To fix the above issue, free the buffer before returning the error.
Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
I need to store address and lvr value for I2C devices without static definition
in DT. This allows secondary master to transmit DEFSLVS command properly.
Main changes between v4 and v5:
- Change in defslvs to use addr and lvr from i2c_dev_desc structure
- Change in CDNS and DW drivers to use addr and lvr from i2c_dev_desc structure
Signed-off-by: Przemyslaw Gaj <pgaj@cadence.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Each iteration of for_each_available_childe_of_node puts the previous
node, but in the case of a return from the middle of the loop, there
is no put, thus causing a memory leak. Add an of_node_put before the
return.
Issue found with Coccinelle.
Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Some I3C device drivers need to know which entry matches the
i3c_device object passed to the probe function
Let's move i3c_device_match_id() to device.c and export it so it can be
used by drivers.
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Pull ic3 updates from Boris Brezillon:
- Drop support for 10-bit I2C addresses
- Add support for limited bus mode
- Fix the Cadence DT binding doc
- Use struct_size() to allocate a DEFSLVS packet
* tag 'i3c/for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux:
i3c: master: Use struct_size() helper
dt-bindings: i3c: cdns: Use correct cells for I2C device
i3c: dw: add limited bus mode support
i3c: add mixed limited bus mode
i3c: fix i2c and i3c scl rate by bus mode
dt-bindings: i3c: Document dropped support for I2C 10 bit devices
i3c: Drop support for I2C 10 bit addresing
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.
So, replace the following form:
sizeof(*defslvs) + ((ndevs - 1) * sizeof(struct i3c_ccc_dev_desc))
with:
struct_size(defslvs, slaves, ndevs - 1)
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
The i3c bus spec defines a bus configuration where i2c devices don't
have a 50ns filter but support SCL running at SDR max rate (12.5MHz).
This patch introduces the limited bus mode so that users can use
a higher speed in presence of i2c devices index 1.
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Currently the I3C framework limits SCL frequency to FM speed when
dealing with a mixed slow bus, even if all I2C devices are FM+ capable.
The core was also not accounting for I3C speed limitations when
operating in mixed slow mode and was erroneously using FM+ speed as the
max I2C speed when operating in mixed fast mode.
Fixes: 3a379bbcea ("i3c: Add core I3C infrastructure")
Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
Cc: Boris Brezillon <bbrezillon@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
