clk: mux: add CLK_MUX_HIWORD_MASK
In both Hisilicon & Rockchip Cortex-A9 based chips, they don't use the
paradigm of reading-changing-writing the register contents.
Instead they use a hiword mask to indicate the changed bits.
When b01 should be set as switching mux, it also needs to indicate
the change by setting hiword mask (b11 << 16).
The patch adds mux flag for this usage.
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
diff --git a/drivers/clk/clk-mux.c b/drivers/clk/clk-mux.c
index 25b1734..614444c 100644
--- a/drivers/clk/clk-mux.c
+++ b/drivers/clk/clk-mux.c
@@ -86,8 +86,12 @@
if (mux->lock)
spin_lock_irqsave(mux->lock, flags);
- val = readl(mux->reg);
- val &= ~(mux->mask << mux->shift);
+ if (mux->flags & CLK_MUX_HIWORD_MASK) {
+ val = mux->mask << (mux->shift + 16);
+ } else {
+ val = readl(mux->reg);
+ val &= ~(mux->mask << mux->shift);
+ }
val |= index << mux->shift;
writel(val, mux->reg);
@@ -111,6 +115,15 @@
struct clk_mux *mux;
struct clk *clk;
struct clk_init_data init;
+ u8 width = 0;
+
+ if (clk_mux_flags & CLK_MUX_HIWORD_MASK) {
+ width = fls(mask) - ffs(mask) + 1;
+ if (width + shift > 16) {
+ pr_err("mux value exceeds LOWORD field\n");
+ return ERR_PTR(-EINVAL);
+ }
+ }
/* allocate the mux */
mux = kzalloc(sizeof(struct clk_mux), GFP_KERNEL);