clk: intel: Improve locking in the driver

Remove/reduce unnecessary spin locking of the code.

Signed-off-by: Rahul Tanwar <rahul.tanwar@linux.intel.com>
Link: https://lore.kernel.org/r/79c0f5f9f5bc512a7e2b5f3c91f6341f28b5854c.1594880946.git.rahul.tanwar@linux.intel.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

diff --git a/drivers/clk/x86/clk-cgu.c b/drivers/clk/x86/clk-cgu.c
index 88ebeb53b10905ea463d7e6b528c954a0f2ce2ce..c379fedfb9f23919e03b76de5c44390848b61559 100644 (file)
--- a/drivers/clk/x86/clk-cgu.c
+++ b/drivers/clk/x86/clk-cgu.c
@@ -420,18 +420,14 @@ lgm_clk_ddiv_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
 {
        struct lgm_clk_ddiv *ddiv = to_lgm_clk_ddiv(hw);
        unsigned int div0, div1, exdiv;
-       unsigned long flags;
        u64 prate;
 
-       spin_lock_irqsave(&ddiv->lock, flags);
        div0 = lgm_get_clk_val(ddiv->membase, ddiv->reg,
                               ddiv->shift0, ddiv->width0) + 1;
        div1 = lgm_get_clk_val(ddiv->membase, ddiv->reg,
                               ddiv->shift1, ddiv->width1) + 1;
        exdiv = lgm_get_clk_val(ddiv->membase, ddiv->reg,
                                ddiv->shift2, ddiv->width2);
-       spin_unlock_irqrestore(&ddiv->lock, flags);
-
        prate = (u64)parent_rate;
        do_div(prate, div0);
        do_div(prate, div1);
@@ -548,24 +544,21 @@ lgm_clk_ddiv_round_rate(struct clk_hw *hw, unsigned long rate,
                div = div * 2;
                div = DIV_ROUND_CLOSEST_ULL((u64)div, 5);
        }
+       spin_unlock_irqrestore(&ddiv->lock, flags);
 
-       if (div <= 0) {
-               spin_unlock_irqrestore(&ddiv->lock, flags);
+       if (div <= 0)
                return *prate;
-       }
 
-       if (lgm_clk_get_ddiv_val(div, &ddiv1, &ddiv2) != 0) {
-               if (lgm_clk_get_ddiv_val(div + 1, &ddiv1, &ddiv2) != 0) {
-                       spin_unlock_irqrestore(&ddiv->lock, flags);
+       if (lgm_clk_get_ddiv_val(div, &ddiv1, &ddiv2) != 0)
+               if (lgm_clk_get_ddiv_val(div + 1, &ddiv1, &ddiv2) != 0)
                        return -EINVAL;
-               }
-       }
 
        rate64 = *prate;
        do_div(rate64, ddiv1);
        do_div(rate64, ddiv2);
 
        /* if predivide bit is enabled, modify rounded rate by factor of 2.5 */
+       spin_lock_irqsave(&ddiv->lock, flags);
        if (lgm_get_clk_val(ddiv->membase, ddiv->reg, ddiv->shift2, 1)) {
                rate64 = rate64 * 2;
                rate64 = DIV_ROUND_CLOSEST_ULL(rate64, 5);