Re: [PATCH v4 2/9] clk: tegra: Add tegra specific clocks

From: Sivaram Nair
Date: Mon Jan 14 2013 - 02:29:00 EST


On Fri, Jan 11, 2013 at 08:46:20AM +0100, Prashant Gaikwad wrote:
> +static int _program_pll(struct clk_hw *hw, struct tegra_clk_pll_freq_table *cfg,
> + unsigned long rate)
> +{
> + struct tegra_clk_pll *pll = to_clk_pll(hw);
> + unsigned long flags = 0;
> + u32 divp, val, old_base;
> + int state;
> +
> + divp = __ffs(cfg->p);
> +
> + if (pll->flags & TEGRA_PLLU)
> + divp ^= 1;
> +
> + if (pll->lock)
> + spin_lock_irqsave(pll->lock, flags);
> +
> + old_base = val = pll_readl_base(pll);
> + val &= ~((divm_mask(pll) << pll->divm_shift) |
> + (divn_mask(pll) << pll->divn_shift) |
> + (divp_mask(pll) << pll->divp_shift));
> + val |= ((cfg->m << pll->divm_shift) |
> + (cfg->n << pll->divn_shift) |
> + (divp << pll->divp_shift));
> + if (val == old_base) {
> + if (pll->lock)
> + spin_unlock_irqrestore(pll->lock, flags);
> + return 0;
> + }
> +
> + state = clk_pll_is_enabled(hw);
> +
> + if (state) {
> + if (pll->lock)
> + spin_unlock_irqrestore(pll->lock, flags);
> +
> + clk_pll_disable(hw);
> + val &= ~(PLL_BASE_BYPASS | PLL_BASE_ENABLE);
> +
> + if (pll->lock)
> + spin_lock_irqsave(pll->lock, flags);

Instead of doing spin_unlock, disable and spin_lock, can't we use
_clk_pll_disable here, without the locks?

regards,
Sivaram
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/