[PATCH v2 2/3] mfd: syscon: Add optional clock support

Fabrice Gasnier
2018-12-12T08:48:51Z

Some system control registers need to be clocked, so the registers can
be accessed. Add an optional clock and attach it to regmap.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
---
drivers/mfd/syscon.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)

diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index b6d05cd..a0ba4ff 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -12,6 +12,7 @@
* (at your option) any later version.
*/

+#include <linux/clk.h>
#include <linux/err.h>
#include <linux/hwspinlock.h>
#include <linux/io.h>
@@ -45,6 +46,7 @@ struct syscon {

static struct syscon *of_syscon_register(struct device_node *np)
{
+ struct clk *clk;
struct syscon *syscon;
struct regmap *regmap;
void __iomem *base;
@@ -119,6 +121,18 @@ static struct syscon *of_syscon_register(struct device_node *np)
goto err_regmap;
}

+ clk = of_clk_get(np, 0);
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ /* clock is optional */
+ if (ret != -ENOENT)
+ goto err_clk;
+ } else {
+ ret = regmap_mmio_attach_clk(regmap, clk);
+ if (ret)
+ goto err_attach;
+ }
+
syscon->regmap = regmap;
syscon->np = np;

@@ -128,6 +142,11 @@ static struct syscon *of_syscon_register(struct device_node *np)

return syscon;

+err_attach:
+ if (!IS_ERR(clk))
+ clk_put(clk);
+err_clk:
+ regmap_exit(regmap);
err_regmap:
iounmap(base);
err_map:
--
1.9.1