ARM: S5PV210: Correct clock register properties
1. Corrected shift values of I2S and UART clocks (CLK_GATE_IP3), which were
defined incorrectly.
2. Corrected shift values of sclk_audio, uclk1, sclk_fimd, sclk_mmc,
sclk_spi, sclk_pwm, which had duplicated .enable/.ctrlbit with their
twins defined in struct clk init_clocks_disable[] and struct clk
init_clocks[]. We've changed their .enable/.ctrlbit to use CLK_SRC_MASK
register to avoid the duplicated clock problem described below.
NOTE: Duplicated Clock Problem
Please note that each clock definition should access different control
register; otherwise, the system may suffer lockups. For example, if we
have two clock definitions "a" and "b" which access the same register
(and the shift value). Then, when we do:
module A
clk = clk_get("a");
clk->clk_enable(clk);
module B (context switch)
clk = clk_get("b");
clk->clk_enable(clk);
do something with clk.
clk->clk_disable(clk);
module A (context switch)
do something with clk
* At this point, the system may hang.
Therefore, there should be no clock definitions with the same contol
register/shift. If we need to create "aliases", then, creating child
clocks sharing the clock should be fine.
3. Corrected other sclk_* shift values and access registers.
Signed-off-by: NMyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
[kgene.kim@samsung.com: minor title and message fix]
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>
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