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| author | Stephen Boyd <sboyd@kernel.org> | 2019-04-19 23:06:58 +0300 |
|---|---|---|
| committer | Stephen Boyd <sboyd@kernel.org> | 2019-04-19 23:06:58 +0300 |
| commit | ac71e68746a3286458bb5d8792111c7bc508195f (patch) | |
| tree | 74a2c387a6fdb4bf26801f60eba91db6b4037909 /drivers/clk | |
| parent | 5a7efdacb9dda1c35fb414d57b3e16d520e2c0db (diff) | |
| parent | 1054e4dd1cbbb7bf5cc836832648f9972134ef67 (diff) | |
| download | linux-ac71e68746a3286458bb5d8792111c7bc508195f.tar.xz | |
Merge tag 'clk-fixes-for-5.1' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux into clk-fixes
Pull Allwinner clk fixes from Maxime Ripard:
- Some fixes for odd cases of the NKMP clocks
* tag 'clk-fixes-for-5.1' of https://git.kernel.org/pub/scm/linux/kernel/git/sunxi/linux:
clk: sunxi-ng: nkmp: Explain why zero width check is needed
clk: sunxi-ng: nkmp: Avoid GENMASK(-1, 0)
Diffstat (limited to 'drivers/clk')
| -rw-r--r-- | drivers/clk/sunxi-ng/ccu_nkmp.c | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/drivers/clk/sunxi-ng/ccu_nkmp.c b/drivers/clk/sunxi-ng/ccu_nkmp.c index 9b49adb20d07..cbcdf664f336 100644 --- a/drivers/clk/sunxi-ng/ccu_nkmp.c +++ b/drivers/clk/sunxi-ng/ccu_nkmp.c @@ -167,7 +167,7 @@ static int ccu_nkmp_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct ccu_nkmp *nkmp = hw_to_ccu_nkmp(hw); - u32 n_mask, k_mask, m_mask, p_mask; + u32 n_mask = 0, k_mask = 0, m_mask = 0, p_mask = 0; struct _ccu_nkmp _nkmp; unsigned long flags; u32 reg; @@ -186,10 +186,24 @@ static int ccu_nkmp_set_rate(struct clk_hw *hw, unsigned long rate, ccu_nkmp_find_best(parent_rate, rate, &_nkmp); - n_mask = GENMASK(nkmp->n.width + nkmp->n.shift - 1, nkmp->n.shift); - k_mask = GENMASK(nkmp->k.width + nkmp->k.shift - 1, nkmp->k.shift); - m_mask = GENMASK(nkmp->m.width + nkmp->m.shift - 1, nkmp->m.shift); - p_mask = GENMASK(nkmp->p.width + nkmp->p.shift - 1, nkmp->p.shift); + /* + * If width is 0, GENMASK() macro may not generate expected mask (0) + * as it falls under undefined behaviour by C standard due to shifts + * which are equal or greater than width of left operand. This can + * be easily avoided by explicitly checking if width is 0. + */ + if (nkmp->n.width) + n_mask = GENMASK(nkmp->n.width + nkmp->n.shift - 1, + nkmp->n.shift); + if (nkmp->k.width) + k_mask = GENMASK(nkmp->k.width + nkmp->k.shift - 1, + nkmp->k.shift); + if (nkmp->m.width) + m_mask = GENMASK(nkmp->m.width + nkmp->m.shift - 1, + nkmp->m.shift); + if (nkmp->p.width) + p_mask = GENMASK(nkmp->p.width + nkmp->p.shift - 1, + nkmp->p.shift); spin_lock_irqsave(nkmp->common.lock, flags); |