user/sven/linux.git/include/linux/clk-provider.h, branch v4.14.136

clk: fractional-divider: check parent rate only if flag is set

2019-04-05T20:31:31Z

[ Upstream commit d13501a2bedfbea0983cc868d3f1dc692627f60d ] Custom approximation of fractional-divider may not need parent clock rate checking. For example Rockchip SoCs work fine using grand parent clock rate even if target rate is greater than parent. This patch checks parent clock rate only if CLK_SET_RATE_PARENT flag is set. For detailed example, clock tree of Rockchip I2S audio hardware. - Clock rate of CPLL is 1.2GHz, GPLL is 491.52MHz. - i2s1_div is integer divider can divide N (N is 1~128). Input clock is CPLL or GPLL. Initial divider value is N = 1. Ex) PLL = CPLL, N = 10, i2s1_div output rate is CPLL / 10 = 1.2GHz / 10 = 120MHz - i2s1_frac is fractional divider can divide input to x/y, x and y are 16bit integer. CPLL --> | selector | ---> i2s1_div -+--> | selector | --> I2S1 MCLK GPLL --> | | ,--------------' | | `--> i2s1_frac ---> | | Clock mux system try to choose suitable one from i2s1_div and i2s1_frac for master clock (MCLK) of I2S1. Bad scenario as follows: - Try to set MCLK to 8.192MHz (32kHz audio replay) Candidate setting is - i2s1_div: GPLL / 60 = 8.192MHz i2s1_div candidate is exactly same as target clock rate, so mux choose this clock source. i2s1_div output rate is changed 491.52MHz -> 8.192MHz - After that try to set to 11.2896MHz (44.1kHz audio replay) Candidate settings are - i2s1_div : CPLL / 107 = 11.214945MHz - i2s1_frac: i2s1_div = 8.192MHz This is because clk_fd_round_rate() thinks target rate (11.2896MHz) is higher than parent rate (i2s1_div = 8.192MHz) and returns parent clock rate. Above is current upstreamed behavior. Clock mux system choose i2s1_div, but this clock rate is not acceptable for I2S driver, so users cannot replay audio. Expected behavior is: - Try to set master clock to 11.2896MHz (44.1kHz audio replay) Candidate settings are - i2s1_div : CPLL / 107 = 11.214945MHz - i2s1_frac: i2s1_div * 147/6400 = 11.2896MHz Change i2s1_div to GPLL / 1 = 491.52MHz at same time. If apply this commit, clk_fd_round_rate() calls custom approximate function of Rockchip even if target rate is higher than parent. Custom function changes both grand parent (i2s1_div) and parent (i2s_frac) settings at same time. Clock mux system can choose i2s1_frac and audio works fine. Signed-off-by: Katsuhiro Suzuki Reviewed-by: Heiko Stuebner [sboyd@kernel.org: Make function into a macro instead] Signed-off-by: Stephen Boyd Signed-off-by: Sasha Levin

clk: honor CLK_MUX_ROUND_CLOSEST in generic clk mux

2018-06-20T19:02:42Z

[ Upstream commit 4ad69b80e886a845f56ce0a3d10211208693d92b ] CLK_MUX_ROUND_CLOSEST is part of the clk_mux documentation but clk_mux directly calls __clk_mux_determine_rate(), which overrides the flag. As result, if clk_mux is instantiated with CLK_MUX_ROUND_CLOSEST, the flag will be ignored and the clock rounded down. To solve this, this patch expose clk_mux_determine_rate_flags() in the clk-provider API and uses it in the determine_rate() callback of clk_mux. Fixes: 15a02c1f6dd7 ("clk: Add __clk_mux_determine_rate_closest") Signed-off-by: Jerome Brunet Signed-off-by: Stephen Boyd Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

clk: divider: fix incorrect usage of container_of

2018-04-12T10:32:13Z

[ Upstream commit 12a26c298d2a8b1cab498533fa65198e49e3afd3 ] divider_recalc_rate() is an helper function used by clock divider of different types, so the structure containing the 'hw' pointer is not always a 'struct clk_divider' At the following line: > div = _get_div(table, val, flags, divider->width); in several cases, the value of 'divider->width' is garbage as the actual structure behind this memory is not a 'struct clk_divider' Fortunately, this width value is used by _get_val() only when CLK_DIVIDER_MAX_AT_ZERO flag is set. This has never been the case so far when the structure is not a 'struct clk_divider'. This is probably why we did not notice this bug before Fixes: afe76c8fd030 ("clk: allow a clk divider with max divisor when zero") Signed-off-by: Jerome Brunet Acked-by: Alexandre Belloni Acked-by: Sylvain Lemieux Signed-off-by: Stephen Boyd Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

clk: gate: expose clk_gate_ops::is_enabled

2017-09-01T01:35:45Z

This patch exposes clk_gate_ops::is_enabled as functions that can be directly called and assigned in places like this so we don't need wrapper functions that do nothing besides forward the call. Signed-off-by: Gabriel Fernandez Suggested-by: Stephen Boyd Signed-off-by: Stephen Boyd

clk: fractional-divider: allow overriding of approximation

2017-08-08T15:39:48Z

Fractional dividers may have special requirements concerning numerator and denominator selection that differ from just getting the best approximation. For example on Rockchip socs the denominator must be at least 20 times larger than the numerator to generate precise clock frequencies. Therefore add the ability to provide custom approximation functions. Signed-off-by: Elaine Zhang Acked-by: Stephen Boyd Signed-off-by: Heiko Stuebner

clk: divider: Make divider_round_rate take the parent clock

2017-06-07T13:32:12Z

So far, divider_round_rate only considers the parent clock returned by clk_hw_get_parent. This works fine on clocks that have a single parents, this doesn't work on muxes, since we will only consider the first parent, while other parents may totally be able to provide a better combination. Clocks in that case cannot use divider_round_rate, so would have to come up with a very similar logic to work around it. Instead of having to do something like this, and duplicate that logic everywhere, create a divider_round_rate parent to allow caller to give an additional parameter for the parent clock to consider. Reviewed-by: Chen-Yu Tsai Signed-off-by: Maxime Ripard Acked-by: Stephen Boyd Signed-off-by: Chen-Yu Tsai

clk: core: add __init decoration for CLK_OF_DECLARE_DRIVER function

2016-10-17T22:27:27Z

The new introduced macro CLK_OF_DECLARE_DRIVER is usually used to declare clock driver init functions, which are mostly decorated with __init. Add __init decoration for CLK_OF_DECLARE_DRIVER function to avoid causing section mismatch warnings on client clock drivers. Signed-off-by: Shawn Guo Fixes: c7296c51ce5d ("clk: core: New macro CLK_OF_DECLARE_DRIVER") Signed-off-by: Stephen Boyd

clk: change the type of clk_hw_onecell_data.num to unsigned int

2016-09-23T21:44:03Z

The "num" is the number of clk_hw entries in the structure, so "unsigned int" would be a better fit. (size_t looks like data size we count by byte.) Besides, struct clk_onecell_data already uses unsigned int for "clk_num". Signed-off-by: Masahiro Yamada Signed-off-by: Stephen Boyd

clk: return unsigned int in dummy non-OF of_clk_get_parent_count()

2016-08-26T19:27:28Z

In the commit 929e7f3bc7b82 ("clk: Make of_clk_get_parent_count() return unsigned ints") of_clk_get_parent_count has been modified to return unsigned int. There is also a dummy implementation of the same function for configs without CONFIG_OF. For the consistency it should be updated as well. Signed-off-by: Rafał Miłecki Signed-off-by: Stephen Boyd

clk: core: New macro CLK_OF_DECLARE_DRIVER

2016-08-13T01:00:34Z

This will be used by drivers that requires initialization at of_clk_init() time and also during platform device probing. Signed-off-by: Ricardo Ribalda Delgado Signed-off-by: Stephen Boyd