msm: clock: Clean up handoff function return values
The intended interpretation of handoff function return value was for 1 or
true to indicate that a handoff of a running clock had been successfully
performed, and 0 or false to indicate that it had not (either because the
clock was off or the rate was invalid).
Some handoff functions added later, however, used the value of 0 to mean
something else: that the handoff of some state was successful, but the
enabled/disabled state of the clock was not checked.
The vague definitions for the return codes of these functions make
it difficult to understand their intended behaviour. Address this by
using an enum of return codes so that their intentions are obvious.
Also update the functions that did not check enabled/disabled state
to do so and return meaningful values.
Change-Id: Iebf4c9e4b358379f7f048a720888b299dc9ee8e5
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
diff --git a/arch/arm/mach-msm/clock-local.c b/arch/arm/mach-msm/clock-local.c
index 3546ce0..acda059 100644
--- a/arch/arm/mach-msm/clock-local.c
+++ b/arch/arm/mach-msm/clock-local.c
@@ -567,34 +567,36 @@
}
/* Disable hw clock gating if not set at boot */
-static void branch_handoff(struct branch *clk, struct clk *c)
+enum handoff branch_handoff(struct branch *clk, struct clk *c)
{
if (!branch_in_hwcg_mode(clk)) {
clk->hwcg_mask = 0;
c->flags &= ~CLKFLAG_HWCG;
+ if (readl_relaxed(clk->ctl_reg) & clk->en_mask)
+ return HANDOFF_ENABLED_CLK;
} else {
c->flags |= CLKFLAG_HWCG;
}
+ return HANDOFF_DISABLED_CLK;
}
-int branch_clk_handoff(struct clk *c)
+enum handoff branch_clk_handoff(struct clk *c)
{
struct branch_clk *clk = to_branch_clk(c);
- branch_handoff(&clk->b, &clk->c);
- return 0;
+ return branch_handoff(&clk->b, &clk->c);
}
-int rcg_clk_handoff(struct clk *c)
+enum handoff rcg_clk_handoff(struct clk *c)
{
struct rcg_clk *clk = to_rcg_clk(c);
uint32_t ctl_val, ns_val, md_val, ns_mask;
struct clk_freq_tbl *freq;
-
- branch_handoff(&clk->b, &clk->c);
+ enum handoff ret;
ctl_val = readl_relaxed(clk->b.ctl_reg);
- if (!(ctl_val & clk->root_en_mask))
- return 0;
+ ret = branch_handoff(&clk->b, &clk->c);
+ if (ret == HANDOFF_DISABLED_CLK)
+ return HANDOFF_DISABLED_CLK;
if (clk->bank_info) {
const struct bank_masks *bank_masks = clk->bank_info;
@@ -611,7 +613,8 @@
ns_mask = clk->ns_mask;
md_val = clk->md_reg ? readl_relaxed(clk->md_reg) : 0;
}
-
+ if (!ns_mask)
+ return HANDOFF_UNKNOWN_RATE;
ns_val = readl_relaxed(clk->ns_reg) & ns_mask;
for (freq = clk->freq_tbl; freq->freq_hz != FREQ_END; freq++) {
if ((freq->ns_val & ns_mask) == ns_val &&
@@ -621,12 +624,12 @@
}
}
if (freq->freq_hz == FREQ_END)
- return 0;
+ return HANDOFF_UNKNOWN_RATE;
clk->current_freq = freq;
c->rate = freq->freq_hz;
- return 1;
+ return HANDOFF_ENABLED_CLK;
}
int pll_vote_clk_enable(struct clk *clk)
@@ -1058,12 +1061,15 @@
return n > clk->max_div ? -ENXIO : n;
}
-static int cdiv_clk_handoff(struct clk *c)
+static enum handoff cdiv_clk_handoff(struct clk *c)
{
struct cdiv_clk *clk = to_cdiv_clk(c);
+ enum handoff ret;
u32 reg_val;
- branch_handoff(&clk->b, &clk->c);
+ ret = branch_handoff(&clk->b, &clk->c);
+ if (ret == HANDOFF_DISABLED_CLK)
+ return ret;
reg_val = readl_relaxed(clk->ns_reg);
if (reg_val & clk->ext_mask) {
@@ -1073,7 +1079,7 @@
clk->cur_div = (reg_val & (clk->max_div - 1)) + 1;
}
- return 0;
+ return HANDOFF_ENABLED_CLK;
}
static void cdiv_clk_enable_hwcg(struct clk *c)