Commit Graph

18 Commits

Author SHA1 Message Date
Arvind Yadav
bd329f028f slimbus: core: use put_device() instead of kfree()
Never directly free @dev after calling device_register(), even
if it returned an error! Always use put_device() to give up the
reference initialized.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-15 17:55:52 +01:00
Srinivas Kandagatla
fc6b1f3d60 slimbus: qcom: add HAS_IOMEM dependency
Below build failure was reported on UML,
ERROR: "devm_ioremap_resource" [drivers/slimbus/slim-qcom-ctrl.ko] undefined!
ERROR: "__ioread32_copy" [drivers/slimbus/slim-qcom-ctrl.ko] undefined!
ERROR: "__iowrite32_copy" [drivers/slimbus/slim-qcom-ctrl.ko] undefined!
ERROR: "devm_ioremap" [drivers/slimbus/slim-qcom-ctrl.ko] undefined!

This patch fixes it by making qcom slimbus depend on HAS_IOMEM, as
these are only defined when HAS_IOMEM is selected.

Reported-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-09 17:01:15 +01:00
Wei Yongjun
ff595a3348 slimbus: qcom: Fix return value check in qcom_slim_probe()
In case of error, the function devm_ioremap_resource() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should
be replaced with IS_ERR().

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-09 17:00:13 +01:00
Wei Yongjun
f8d2c8ea57 slimbus: Fix missing unlock on error in slim_msg_response()
Add the missing unlock before return from function slim_msg_response()
in the error handling case.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-09 17:00:13 +01:00
Wei Yongjun
ab9b3de701 slimbus: Use GFP_ATOMIC under spin lock
A spin lock is taken here so we should use GFP_ATOMIC.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-09 17:00:13 +01:00
Colin Ian King
c88c8d7aae slimbus: make functions slim_ack_txn and slim_alloc_txbuf static
The functions slim_ack_txn and slim_alloc_txbuf are local to the
source and do not need to be in global scope, so make them static.

Cleans up sparse warnings:
symbol 'slim_ack_txn' was not declared. Should it be static?
symbol 'slim_alloc_txbuf' was not declared. Should it be static?

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-09 17:00:13 +01:00
Colin Ian King
551b9ee472 slimbus: fix retries comparison to correctly identify failed allocation
Currently the check for too many retries fails because retries is actually
-1 when the retry loop terminates if no pbuf can be allocated because of
the post decrement on retries.  Fix this by not comparing retries with zero
but instead check if it is negative.

Detected by CoverityScan, CID#1463143 ("Logically dead code") and
CID#1463144 ("Dereference after null check")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-09 17:00:13 +01:00
Colin Ian King
7dde60c06c slimbus: avoid null pointer dereference on msg
The pointer msg is checked to see if it is null at the start of
the function and jumps to the error exit label reterr that then
dereferences msg when it prints a dev_err error message. Avoid
this potential null pointer dereference by only printing the
error message if msg is not null.

Detected by CoverityScan, CID#1463141 ("Dereference after null check")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-09 17:00:13 +01:00
Arnd Bergmann
c127f98ba9 slimbus: qcom-ctrl: use normal allocation
The previous patch addressed a warning but not the cause:

drivers/slimbus/qcom-ctrl.c: In function 'qcom_slim_probe':
drivers/slimbus/qcom-ctrl.c:584:9: error: passing argument 3 of 'dmam_alloc_coherent' from incompatible pointer type [-Werror=incompatible-pointer-types]

There are two things wrong here:

- The naming is very confusing, we now have a member named 'phys'
  that doesn't refer to a phys_addr_t but a dma_addr_t. If we needed
  a dma address, it should be named 'dma' to avoid confusion, and
  to make it less likely that someone passes it into a function that
  expects a physical address.

- The dma address is not used at all at this point. It may have been
  designed to support DMA in the future, but today it doesn't, so
  the only effect right now is to make transfers artificially slower
  by using uncached memory instead of cached memory for a temporary
  buffer.

This removes the unused structure member and instead changes the code
to call devm_kcalloc(), which matches the usage of the 'base' pointer
as an array of temporary buffers.

Fixes: db809859c8 ("slimbus: qcom: fix incompatible pointer warning")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02 17:05:17 +01:00
Srinivas Kandagatla
db809859c8 slimbus: qcom: fix incompatible pointer warning
One of the pointer passed to dmam_alloc_coherent seems to be
phys_addr_t * instead of dma_addr_t *. This address will be
used by dma apis, so change this to proper type.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-31 17:52:59 +01:00
Sagar Dharia
c088c335b4 slimbus: qcom: Add runtime-pm support using clock-pause
Slimbus HW mandates that clock-pause sequence has to be executed
before disabling relevant interface and core clocks.
Runtime-PM's autosuspend feature is used here to enter/exit low
power mode for Qualcomm's Slimbus controller. Autosuspend feature
enables driver to avoid changing power-modes too frequently since
entering clock-pause is an expensive sequence

Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19 11:01:03 +01:00
Sagar Dharia
ad7fcbc308 slimbus: qcom: Add Qualcomm Slimbus controller driver
This controller driver programs manager, interface, and framer
devices for Qualcomm's slimbus HW block.
Manager component currently implements logical address setting,
and messaging interface.
Interface device reports bus synchronization information, and framer
device clocks the bus from the time it's woken up, until clock-pause
is executed by the manager device.

Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19 11:01:03 +01:00
Srinivas Kandagatla
ce96188b12 slimbus: core: add common defines required for controllers
This patch adds some common constant defines which are required
for qcom slim controller driver.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19 11:01:03 +01:00
Sagar Dharia
4b14e62ad3 slimbus: Add support for 'clock-pause' feature
Per SLIMbus specification, a reconfiguration sequence known as
'clock pause' needs to be broadcast over the bus while entering low-
power mode. Clock-pause is initiated by the controller driver.
To exit clock-pause, controller typically wakes up the framer device.
Since wakeup precedure is controller-specific, framework calls it via
controller's function pointer to invoke it.

Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19 11:01:03 +01:00
Sagar Dharia
afbdcc7c38 slimbus: Add messaging APIs to slimbus framework
SLIMbus devices use value-element, and information elements to
control device parameters (e.g. value element is used to represent
gain for codec, information element is used to represent interrupt
status for codec when codec interrupt fires).
Messaging APIs are used to set/get these value and information
elements. SLIMbus specification uses 8-bit "transaction IDs" for
messages where a read-value is anticipated. Framework uses a table
of pointers to store those TIDs and responds back to the caller in
O(1).
Caller can do synchronous and asynchronous reads/writes.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19 11:01:02 +01:00
Srinivas Kandagatla
7588a511bd slimbus: core: add support to device tree helper
This patch adds support to parse slim devices from device tree.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19 11:01:02 +01:00
Sagar Dharia
46a2bb5a7f slimbus: core: Add slim controllers support
This patch adds support to slim controllers in the slim core,
including some utility functions invoked by the controller and
slim device drivers.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19 11:01:02 +01:00
Sagar Dharia
3648e78ec7 slimbus: Add SLIMbus bus type
SLIMbus (Serial Low Power Interchip Media Bus) is a specification
developed by MIPI (Mobile Industry Processor Interface) alliance.
SLIMbus is a 2-wire implementation, which is used to communicate with
peripheral components like audio-codec.
SLIMbus uses Time-Division-Multiplexing to accommodate multiple data
channels, and control channel. Control channel has messages to do
device-enumeration, messages to send/receive control-data to/from
SLIMbus devices, messages for port/channel management, and messages to
do bandwidth allocation.
The framework supports multiple instances of the bus (1 controller per
bus), and multiple slave devices per controller.

This patch adds support to basic silmbus core which includes support to
SLIMbus type, slimbus device registeration and some basic data structures.

Signed-off-by: Sagar Dharia <sdharia@codeaurora.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19 11:01:02 +01:00