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path: root/drivers/clk/clk-divider.c
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2013-04-03clk: divider: Introduce CLK_DIVIDER_ALLOW_ZERO flagSoren Brinkmann
Dividers which have CLK_DIVIDER_ONE_BASED set have a redundant state, being a divider value of zero. Some hardware implementations allow a zero divider which simply doesn't alter the frequency. I.e. it acts like a divide by one or bypassing the divider. This flag is used to handle such HW in the clk-divider model. Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2013-01-18clk-divider: fix macrosJames Hogan
The macro is_power_of_two() in clk-divider.c was defined as !(i & ~i) which is always true. Instead use is_power_of_2() from log2.h. Also add brackets around the macro arguments in div_mask to avoid any future operator precedence problems. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Mike Turquette <mturquette@linaro.org> [mturquette@linaro.org: use log2.h per Joe Perches; update changelog]
2012-07-11clk: Add CLK_IS_BASIC flag to identify basic clocksRajendra Nayak
Most platforms end up using a mix of basic clock types and some which use clk_hw_foo struct for filling in custom platform information when the clocks don't fit into basic types supported. In platform code, its useful to know if a clock is using a basic type or clk_hw_foo, which helps platforms know if they can safely use to_clk_hw_foo to derive the clk_hw_foo pointer from clk_hw. Mark all basic clocks with a CLK_IS_BASIC flag. Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-07-11clk: Add support for rate table based dividersRajendra Nayak
Some divider clks do not have any obvious relationship between the divider and the value programmed in the register. For instance, say a value of 1 could signify divide by 6 and a value of 2 could signify divide by 4 etc. Also there are dividers where not all values possible based on the bitfield width are valid. For instance a 3 bit wide bitfield can be used to program a value from 0 to 7. However its possible that only 0 to 4 are valid values. All these cases need the platform code to pass a simple table of divider/value tuple, so the framework knows the exact value to be written based on the divider calculation and can also do better error checking. This patch adds support for such rate table based dividers and as part of the support adds a new registration function 'clk_register_divider_table()' and a new macro for static definition 'DEFINE_CLK_DIVIDER_TABLE'. Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-07-11clk: Add support for power of two type dividersRajendra Nayak
Quite often dividers and the value programmed in the register have a relation of 'power of two', something like value div 0 1 1 2 2 4 3 8... Add support for such dividers as part of clk-divider. The clk-divider flag 'CLK_DIVIDER_POWER_OF_TWO' should be used to define such clocks. Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-05-02clk: Use a separate struct for holding init data.Saravana Kannan
Create a struct clk_init_data to hold all data that needs to be passed from the platfrom specific driver to the common clock framework during clock registration. Add a pointer to this struct inside clk_hw. This has several advantages: * Completely hides struct clk from many clock platform drivers and static clock initialization code that don't care for static initialization of the struct clks. * For platforms that want to do complete static initialization, it removed the need to directly mess with the struct clk's fields while still allowing to statically allocate struct clk. This keeps the code more future proof even if they include clk-private.h. * Simplifies the generic clk_register() function and allows adding optional fields in the future without modifying the function signature. * Simplifies the static initialization of clocks on all platforms by removing the need for forward delcarations or convoluted macros. Signed-off-by: Saravana Kannan <skannan@codeaurora.org> [mturquette@linaro.org: kept DEFINE_CLK_* macros and __clk_init] Signed-off-by: Mike Turquette <mturquette@linaro.org> Cc: Andrew Lunn <andrew@lunn.ch> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Jeremy Kerr <jeremy.kerr@canonical.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergman <arnd.bergmann@linaro.org> Cc: Paul Walmsley <paul@pwsan.com> Cc: Shawn Guo <shawn.guo@freescale.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Jamie Iles <jamie@jamieiles.com> Cc: Richard Zhao <richard.zhao@linaro.org> Cc: Saravana Kannan <skannan@codeaurora.org> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Linus Walleij <linus.walleij@stericsson.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Amit Kucheria <amit.kucheria@linaro.org> Cc: Deepak Saxena <dsaxena@linaro.org> Cc: Grant Likely <grant.likely@secretlab.ca>
2012-04-24clk: pass parent_rate into .set_rateShawn Guo
For most of .set_rate implementation, parent_rate will be used, so just like passing parent_rate into .recalc_rate, let's pass parent_rate into .set_rate too. It also updates the kernel doc for .set_rate ops. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-04-24clk: always pass parent_rate into .round_rateShawn Guo
The parent_rate will likely be used by most .round_rate implementation no matter whether flag CLK_SET_RATE_PARENT is set or not, so let's always pass parent_rate into .round_rate. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-04-24clk: basic: improve parent_names & return errorsMike Turquette
This patch is the basic clk version of 'clk: core: copy parent_names & return error codes'. The registration functions are changed to allow the core code to copy the array of strings and allow platforms to declare those arrays as __initdata. This patch also converts all of the basic clk registration functions to return error codes which better aligns them with the existing clk.h api. Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-04-24clk: add "const" for clk_ops of basic clksShawn Guo
The clk_ops of basic clks should have "const" to match the definition in "struct clk" and clk_register prototype. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-04-24clk: remove unnecessary EXPORT_SYMBOL_GPLShawn Guo
It makes no sense to have EXPORT_SYMBOL_GPL on static functions. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Mike Turquette <mturquette@linaro.org>
2012-03-16clk: basic clock hardware typesMike Turquette
Many platforms support simple gateable clocks, fixed-rate clocks, adjustable divider clocks and multi-parent multiplexer clocks. This patch introduces basic clock types for the above-mentioned hardware which share some common characteristics. Based on original work by Jeremy Kerr and contribution by Jamie Iles. Dividers and multiplexor clocks originally contributed by Richard Zhao & Sascha Hauer. Signed-off-by: Mike Turquette <mturquette@linaro.org> Signed-off-by: Mike Turquette <mturquette@ti.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Tested-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Rob Herring <rob.herring@calxeda.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Jeremy Kerr <jeremy.kerr@canonical.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Arnd Bergman <arnd.bergmann@linaro.org> Cc: Paul Walmsley <paul@pwsan.com> Cc: Shawn Guo <shawn.guo@freescale.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Jamie Iles <jamie@jamieiles.com> Cc: Richard Zhao <richard.zhao@linaro.org> Cc: Saravana Kannan <skannan@codeaurora.org> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Linus Walleij <linus.walleij@stericsson.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Amit Kucheria <amit.kucheria@linaro.org> Cc: Deepak Saxena <dsaxena@linaro.org> Cc: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Arnd Bergmann <arnd@arndb.de>