The devfreq structure instance contains the governor_name and a governor instance. When need to show the governor name, better to use the name of devfreq_governor structure. So, governor_name variable in struct devfreq is a redundant and unneeded variable. Remove the redundant governor_name of struct devfreq and then use the name of devfreq_governor instance. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
DEVFREQ supports the default governors like performance, simple_ondemand and
also allows the devfreq driver to add their own governor like tegra30-devfreq.c
according to their requirement. In result, some sysfs attributes are useful
or not useful. Prior to that the user can access all sysfs attributes
regardless of the available attributes.
So, clarify the access permission of sysfs attributes according to governor.
When adding the devfreq governor, can specify the available attribute
information by using DEVFREQ_GOV_ATTR_* constant variable. The user can
read or write the sysfs attributes in accordance to the specified attributes.
When adding the governor, can add the following attributes
according to the governor feature.
[Definition for speific sysfs attributes]
- DEVFREQ_GOV_ATTR_POLLING_INTERVAL to update polling interval for timer.
: /sys/class/devfreq/[devfreq dev name]/polling_interval
- DEVFREQ_GOV_ATTR_TIMER to change the type of timer on either deferrable
or dealyed timer.
: /sys/class/devfreq/[devfreq dev name]/timer
And all devfreq governors have to support the following common attributes.
The common attributes are added to devfreq class by default.
- governor
- available_governors
- available_frequencies
- cur_freq
- target_freq
- min_freq
- max_freq
- trans_stat
[Table of governor attribute flags for devfreq governors]
------------------------------------------------------------------------------
| simple | perfor | power | user | passive | tegra30
| ondemand | mance | save | space| |
------------------------------------------------------------------------------
governor | O | O | O | O | O | O
available_governors | O | O | O | O | O | O
available_frequencies | O | O | O | O | O | O
cur_freq | O | O | O | O | O | O
target_freq | O | O | O | O | O | O
min_freq | O | O | O | O | O | O
max_freq | O | O | O | O | O | O
trans_stat | O | O | O | O | O | O
--------------------------------------------------------
polling_interval | O | X | X | X | X | O
timer | O | X | X | X | X | X
------------------------------------------------------------------------------
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
The devfreq governor is able to have the specific flag as follows
in order to implement the specific feature. For example, devfreq allows
user to change the governors on runtime via sysfs interface.
But, if devfreq device uses 'passive' governor, don't allow user to change
the governor. For this case, define the DEVFREQ_GOV_FLAG_IMMUTABLE
and set it to flag of passive governor.
[Definition for governor flag]
- DEVFREQ_GOV_FLAG_IMMUTABLE
: If immutable flag is set, governor is never changeable to other governors.
- DEVFREQ_GOV_FLAG_IRQ_DRIVEN
: Devfreq core won't schedule polling work for this governor if value is set.
[Table of governor flag for devfreq governors]
------------------------------------------------------------------------------
| simple | perfor | power | user | passive | tegra30
| ondemand | mance | save | space| |
------------------------------------------------------------------------------
immutable | X | X | X | X | O | O
interrupt_driven | X(polling)| X | X | X | X | O (irq)
------------------------------------------------------------------------------
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Add a tracepoint for frequency changes of devfreq devices and use it. Signed-off-by: Matthias Kaehlcke <mka@chromium.org> [cw00.choi: Move print position of tracepoint and add more information] Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
The update_devfreq() and update_passive_devfreq() have the duplicate code when changing the target frequency on final stage. So, unify frequency change code to devfreq_update_target() to remove the duplicate code and to centralize the frequency change code. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Previously, devfreq core support 'devfreq' property in order to get the devfreq device by phandle. But, 'devfreq' property name is not proper on devicetree binding because this name doesn't mean the any h/w attribute. The devfreq core hand over the right to decide the property name for getting the devfreq device on devicetree. Each devfreq driver will decide the property name on devicetree binding and pass the their own property name to devfreq_get_devfreq_by_phandle function. Acked-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Split off part of devfreq_get_devfreq_by_phandle into a separate function. This allows callers to fetch devfreq instances by enumerating devicetree instead of explicit phandles. Acked-by: Krzysztof Kozlowski <krzk@kernel.org> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com> [cw00.choi: Export devfreq_get_devfreq_by_node function and add function to devfreq.h when CONFIG_PM_DEVFREQ is enabled.] Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
The commit 4dc3bab8687f ("PM / devfreq: Add support delayed timer for
polling mode") supports the delayed timer but this commit missed
the adding the timer type to devfreq_summary debugfs node.
Add the timer type to devfreq_summary debugfs.
Fixes: 4dc3bab8687f ("PM / devfreq: Add support delayed timer for polling mode")
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Fix the wrong grammar at the end of code line by using semicolon.
Cc: stable vger.kernel.org
Fixes: 490a421bc575 ("PM / devfreq: Add debugfs support with devfreq_summary file")
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
The commit 66d0e797bf09 ("Revert "PM / devfreq: Modify the device name
as devfreq(X) for sysfs"") roll back the device name from 'devfreqX'
to device name explained in DT. After applied commit 66d0e797bf09,
the indentation of devfreq_summary debugfs node was broken.
So, fix indentaion of devfreq_summary debugfs node as following:
For example on Exynos5422-based Odroid-XU3 board,
$ cat /sys/kernel/debug/devfreq/devfreq_summary
dev parent_dev governor polling_ms cur_freq_Hz min_freq_Hz max_freq_Hz
------------------------------ ------------------------------ --------------- ---------- ------------ ------------ ------------
10c20000.memory-controller null simple_ondemand 0 413000000 165000000 825000000
soc:bus_wcore null simple_ondemand 50 88700000 88700000 532000000
soc:bus_noc soc:bus_wcore passive 0 66600000 66600000 111000000
soc:bus_fsys_apb soc:bus_wcore passive 0 111000000 111000000 222000000
soc:bus_fsys soc:bus_wcore passive 0 75000000 75000000 200000000
soc:bus_fsys2 soc:bus_wcore passive 0 75000000 75000000 200000000
soc:bus_mfc soc:bus_wcore passive 0 83250000 83250000 333000000
soc:bus_gen soc:bus_wcore passive 0 88700000 88700000 266000000
soc:bus_peri soc:bus_wcore passive 0 66600000 66600000 66600000
soc:bus_g2d soc:bus_wcore passive 0 83250000 83250000 333000000
soc:bus_g2d_acp soc:bus_wcore passive 0 0 66500000 266000000
soc:bus_jpeg soc:bus_wcore passive 0 0 75000000 300000000
soc:bus_jpeg_apb soc:bus_wcore passive 0 0 83250000 166500000
soc:bus_disp1_fimd soc:bus_wcore passive 0 0 120000000 200000000
soc:bus_disp1 soc:bus_wcore passive 0 0 120000000 300000000
soc:bus_gscl_scaler soc:bus_wcore passive 0 0 150000000 300000000
soc:bus_mscl soc:bus_wcore passive 0 0 84000000 666000000
Cc: stable@vger.kernel.org
Fixes: 66d0e797bf09 ("Revert "PM / devfreq: Modify the device name as devfreq(X) for sysfs"")
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>