mmc: block: Update error handling if block data is not available

While handling IOCTL command, if the block is not available then in the
bail-out path it is trying to free the block data which will be executed
against NULL pointer.

So, don't attempt to free the block data and only release the IOCTL
data.

CRs-Fixed: 476581
Change-Id: Icba46c861258d2d84b1fae5a2f5fca52ffe54255
Signed-off-by: Pratibhasagar V <pratibha@codeaurora.org>
mmc: core: Allow changing bus frequency for SD/eMMC cards in runtime

Currently, bus frequency is set during the card initialization and
never changed until a new card is inserted. In some low power use
cases, scaling the clock frequencies while the card is in transfer
state would allow power savings. This change allows bus frequency
to be changed after the card initialization.

Change-Id: Iac064221199f69d162d91f5311becd735c15700a
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
mmc: core: Add load based clock scaling support

The SD3.0/eMMC4.5/SDIO3.0 cards can support clock rates upto
200MHz (SDR104 or HS200 bus speed modes). For some workloads
like video playback it isn't necessary for these cards to run
at such high speed. Running at lower frequency, say 50MHz, in
such cases can still meet the deadlines for data transfers.
Scaling down the clock frequency dynamically has huge power
savings not only because the bus is running at lower frequency
but also has an advantage of scaling down the system core
voltage, if supported.

Provide an ondemand clock scaling support similar to cpufreq
ondemand governor having two thresholds, up_threshold and
down_threshold to decide whether to increase the frequency or
scale it down respectively. The sampling interval is in the
order of milliseconds and should be chosen by host drivers that
enable MMC_CAP2_CLK_SCALE capability to take advantage of clock
scaling. The sampling interval mainly depends on the the clock
switching delays and hence a host driver decision. If sampling
interval is too low frequent switching of frequencies can lead
to high power consumption and if sampling interval is too high,
the clock scaling logic would take long time to realize that the
underlying hardware (controller and card) is busy and scale up
the clocks.

Change-Id: I22a5054beec41b0b66b3bf030ddfcf284de448b3
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
mmc: core: Add sysfs entries for dynamic control of clock scaling

Add sysfs attributes to allow dynamic control of clock scaling
parameters. These attributes are used to enable/disable clock
scaling at runtime and change the up_threshold, down_threshold,
and polling_interval values. Complete documentation for these
sysfs entries are provided at "Documentation/mmc/mmc-dev-attrs.txt".

Change-Id: I4753c75c3b3eeea91e93bceba7af2535b793612e
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
mmc: core: claim mmc host while enabling clock scaling from userspace

A race condition can occur while enabling clock scaling and removal
of the card. If the card is removed just after the host->card check
is successful then there could be NULL pointer dereference later.
Claim mmc host before card availability check to avoid this race
condition.

Change-Id: I6339cad5857732ec6b66280940cd6b8b7ed30614
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
mmc: core: run clock scaling only in valid card state

Clock scaling requires the tuning and if the tuning command
is sent to the card in invalid state, tuning procedure will
fail.

With urgent request mechanism implemented, there is a chance
that clock scaling invoked when card is not in a proper state
to receive the tuning command.

This change checks the card state (by sending the status command)
before invoking the clock scaling request.

Change-Id: Icb71a8e74a9afdc70380a5901cd3d28931959e9c
Signed-off-by: Subhash Jadavani <subhashj@codeaurora.org>
mmc: core: Log MMC clock frequency transitions

Use kernel's ftrace support to capture MMC clock frequency
transitions which can be useful for debugging issues related
to power consumption.

Usage:
mount -t debugfs none /sys/kernel/debug
echo 1 > /sys/kernel/debug/tracing/events/mmc/mmc_clk/enable
cat /sys/kernel/debug/tracing/trace_pipe

Change-Id: I25c4ee39dcbe30e7665902a9f723a5a421b55ca3
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
mmc: core: Add support for notifying host driver while scaling clocks

Host drivers can participate in clock scaling by registering
->notify_load host operation, which allows host driver to carry out
platform specific operations for further power savings or increasing
throughput based on whether load is LOW or HIGH respectively. This
can be applicable to non-ultra high speed cards as well so remove
the check for ultra high speed cards to initialize clock scaling.

Change-Id: Icaab9520135e384f5470db68b2f25c5cdce5663a
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
msm: bam_dmux: Fix potential memory leaks

Added code to fix potential memory leaks.

Change-Id: I76f92fc95539feee67600a6ab4a730bbb50643a1
Signed-off-by: Brent Hronik <bhronik@codeaurora.org>
msm: ipc_router: Fix potential leaks and null dereferences

Added null pointer checks to avoid potential null pointer dereferences
and free statements to avoid potential memory leaks

Change-Id: I0553dfe6c61260a700a9dc6a411dcec6483e0eb8
Signed-off-by: Brent Hronik <bhronik@codeaurora.org>
msm: ipc: Access pointers after a successful check

Some pointers in msm_ipc_router_extract_msg function are accessed either
before a NULL pointer check or if one of the conditions in the check is
true.

Fix the code to dereference those pointers only after the pointer is not
NULL and the other associated conditions are true.

CRs-Fixed: 471110
Change-Id: Ic45fe118818caa6985e5e56403ab3cc467174cf6
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org>
msm: camera: Fix camera crash in msm_open_config

Add proper check before accessing mctl handle to
avoid camera crash.

Change-Id: I1413f086ab7d94fe223a814bb16867d1dcc0a4bf
CRs-Fixed: 481757
Signed-off-by: Suresh Vankadara <svankada@codeaurora.org>
msm: camera: Fix camera crash when ctrl_q is empty

Add proper error condition if the list is empty and
return error value to upper layers instead of BUG_ON.

Change-Id: I89237e7a27d5fb1e1fd5f1a8a2dfd7ea9a1afff5
CRs-Fixed: 481759
Signed-off-by: Suresh Vankadara <svankada@codeaurora.org>
cpufreq: Resolve CPUFREQ_NOTIFY issue

When the cpufreq_stat receives the frequency policy notification,
it checks if the frequency table and stats table are present for the cpu.
If both are present, it returns with -EBUSY error to the notification.
Due to this, none of the other registered modules receive this
notification.

If the stat table and sysfs nodes are already created, return 0 instead
of returning EBUSY error.

Change-Id: I1fd4a46e6a65edfc6253c4271288f10912ae2ad7
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
msm:rq_stats: Register for Cpufreq policy notification

Currently the load of the system is calculated using the max
frequency that is read during startup(It does not get updated
when the policy changes). As a result, the average load of the
system is incorrectly calculated and the system might not bring
the cpus online to manage the additional load. This
reduces the performance of the system.

To fix this issue, register rq_stats to receive cpufreq policy
notifications. Update the policy's max frequency when a
notification is received and use that value to calculate the load.

Change-Id: Icc78e28c736c170e198f723fd96c13dfb2dafe8a
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>
Signed-off-by: Anji Jonnala <anjir@codeaurora.org>
mmc: msm_sdcc: Add support for dynamic bus clock vote

SDCC controller on some targets like 8660, 8960, 8064 and their
variants connects with Daytona Fabric (DFAB). To achieve max.
possible performance the DFAB clock is voted to 64MHz at the
cost of some power consumption. Since we now have dynamic clock
scaling for SD/eMMC clock we can also scale the DFAB clock
accordingly without impact on performance but have some power
savings in low throughput cases.

Change-Id: Ic26541d6845b65803aa813d672ccabdfc4658d9c
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
tty: n_smux: Add SMUX documentation

Add SMUX documentation that was missed when the initial
driver was added.

Change-Id: I5b23e451ff48d1eac05b22de3e5f0e017a6f7b0c
Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
msm: mdm: Disable panic on external mdm boot timeout

We now have the ability to not panic when we see a external modem has
not booted up within the expected timeframe. This functionality is
required in order to debug early bootup issues on the mdm's and is
configured via a sysfs flag.

Change-Id: Iac3bf980b239fdbe2ffdc8a5a25b875d47f0384c
Signed-off-by: Ameya Thakur <ameyat@codeaurora.org>
msm: board-8930: Add correct regulators for isa1200 chip

The regulators used by isa1200 in 8930 are differenet from
schematics. So, fix the regualtor entries for isa1200.

CRs-fixed: 473633
Change-Id: I4a8edd1428f93810b7216c4b4efb878c12820925
Signed-off-by: Mohan Pallaka <mpallaka@codeaurora.org>
input: touchscreen: Change the file system permission of synaptic driver

Some of the sysfs files of synaptic driver has "write"
permissions. Change them to "read" only.

CRs-Fixed: 454347

Change-Id: Ic64ebfe30b9fe351e6556951f9d0981077e7a076
Signed-off-by: Shantanu Jain <shjain@codeaurora.org>