Quoting Nicholas Mc Guire (2018-07-15 03:18:24)
> Refactoring of code to make it more readable and at the same time make
> sparse happy again.
>
> Signed-off-by: Nicholas Mc Guire <hof...@osadl.org>
> ---
>
> sparse complained about:
> drivers/clk/st/clkgen-pll.c:225:12: warning: context imbalance in
> 'clkgen_pll_enable' - different lock contexts for basic block
> drivers/clk/st/clkgen-pll.c:267:9: warning: context imbalance in
> 'clkgen_pll_disable' - different lock contexts for basic block
> drivers/clk/st/clkgen-pll.c:413:9: warning: context imbalance in
> 'set_rate_stm_pll3200c32' - different lock contexts for basic block
> drivers/clk/st/clkgen-pll.c:570:9: warning: context imbalance in
> 'set_rate_stm_pll4600c28' - different lock contexts for basic block
>
> Which are technically false positives as the pll->lock which is being
> checked is determined at configuration time, thus the locks are balanced.
> Never the less the refactored code seems more readable and was
> commented to make it clear.
This stuff above should go into the commit text.
>
> Patch was compile tested with: multi_v7_defconfig (implies
> CONFIG_ARCH_STI=y)
>
> Patch is against 4.18-rc4 (localversion-next is next-20180713)
>
> drivers/clk/st/clkgen-pll.c | 51
> +++++++++++++++++++++++++--------------------
> 1 file changed, 28 insertions(+), 23 deletions(-)
I believe this driver is in stasis mode. Not sure anyone is testing this
right now. Please Cc people who have worked on this driver, like Gabriel
Fernandez.
>
> diff --git a/drivers/clk/st/clkgen-pll.c b/drivers/clk/st/clkgen-pll.c
> index 7a7106dc..cbb5184 100644
> --- a/drivers/clk/st/clkgen-pll.c
> +++ b/drivers/clk/st/clkgen-pll.c
> @@ -228,13 +228,13 @@ static int clkgen_pll_enable(struct clk_hw *hw)
> unsigned long flags = 0;
> int ret = 0;
>
> - if (pll->lock)
> + if (pll->lock) {
> + /* stih418 and stih407 */
> spin_lock_irqsave(pll->lock, flags);
> -
> - ret = __clkgen_pll_enable(hw);
> -
> - if (pll->lock)
> + ret = __clkgen_pll_enable(hw);
> spin_unlock_irqrestore(pll->lock, flags);
> + } else
> + ret = __clkgen_pll_enable(hw);
>
> return ret;
> }
> @@ -259,13 +259,13 @@ static void clkgen_pll_disable(struct clk_hw *hw)
> struct clkgen_pll *pll = to_clkgen_pll(hw);
> unsigned long flags = 0;
>
> - if (pll->lock)
> + if (pll->lock) {
> + /* stih418 and stih407 */
> spin_lock_irqsave(pll->lock, flags);
> -
> - __clkgen_pll_disable(hw);
> -
> - if (pll->lock)
> + __clkgen_pll_disable(hw);
> spin_unlock_irqrestore(pll->lock, flags);
> + } else
> + __clkgen_pll_disable(hw);
> }
>
> static int clk_pll3200c32_get_params(unsigned long input, unsigned long
> output,
> @@ -400,15 +400,18 @@ static int set_rate_stm_pll3200c32(struct clk_hw *hw,
> unsigned long rate,
>
> __clkgen_pll_disable(hw);
>
> - if (pll->lock)
> + if (pll->lock) {
> + /* stih407 and stih418 */
> spin_lock_irqsave(pll->lock, flags);
> -
> - CLKGEN_WRITE(pll, ndiv, pll->ndiv);
> - CLKGEN_WRITE(pll, idf, pll->idf);
> - CLKGEN_WRITE(pll, cp, pll->cp);
> -
> - if (pll->lock)
> + CLKGEN_WRITE(pll, ndiv, pll->ndiv);
> + CLKGEN_WRITE(pll, idf, pll->idf);
> + CLKGEN_WRITE(pll, cp, pll->cp);
> spin_unlock_irqrestore(pll->lock, flags);
> + } else {
> + CLKGEN_WRITE(pll, ndiv, pll->ndiv);
> + CLKGEN_WRITE(pll, idf, pll->idf);
> + CLKGEN_WRITE(pll, cp, pll->cp);
> + }
Please don't duplicate this code. The sparse warnings can be fixed by
adding a fake lock acquire to the else of the if condition. We do this
in drivers/clk/clk.c so you should be able to copy it from there.
>
