[PATCH 04/13] clk: core: enforce clk_ops consistency

[mturquette@linaro.org (Mike Turquette)]

Documentation/clk.txt has some handsome ASCII art outlining which
clk_ops are mandatory for a given clock, given the capability of the
hardware.  Enforce those mandates with sanity checks in __clk_init.

Signed-off-by: Mike Turquette <mturquette@linaro.org>
Cc: Arnd Bergman <arnd.bergmann@linaro.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawn.guo@freescale.com>
Cc: Richard Zhao <richard.zhao@linaro.org>
Cc: Saravana Kannan <skannan@codeaurora.org>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Rajendra Nayak <rnayak@ti.com>
Cc: Viresh Kumar <viresh.kumar@st.com>
---
 drivers/clk/clk.c |   14 ++++++++++++++
 1 files changed, 14 insertions(+), 0 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index d83a9e0..9924aec 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1202,6 +1202,20 @@ void __clk_init(struct device *dev, struct clk *clk)
 	if (__clk_lookup(clk->name))
 		goto out;
 
+	/* check that clk_ops are sane.  See Documentation/clk.txt */
+	if (clk->ops->set_rate &&
+			!(clk->ops->round_rate && clk->ops->recalc_rate)) {
+		pr_warning("%s: %s must implement .round_rate & .recalc_rate\n",
+				__func__, clk->name);
+		goto out;
+	}
+
+	if (clk->ops->set_parent && !clk->ops->get_parent) {
+		pr_warning("%s: %s must implement .get_parent & .set_parent\n",
+				__func__, clk->name);
+		goto out;
+	}
+
 	/* throw a WARN if any entries in parent_names are NULL */
 	for (i = 0; i < clk->num_parents; i++)
 		WARN(!clk->parent_names[i],
-- 
1.7.5.4