summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorGregory CLEMENT <gregory.clement@free-electrons.com>2018-01-16 17:35:39 +0100
committerWolfram Sang <wsa@the-dreams.de>2018-01-26 18:51:03 +0100
commit1534156e999735fe0befad958e1447600c0c20e7 (patch)
treed846509f8e3b074a5af5e47e3b690f8c3fa7969c
parenta9e94bb80ea6d53745eb5ca86597696735565fb3 (diff)
downloadlinux-0-day-1534156e999735fe0befad958e1447600c0c20e7.tar.gz
linux-0-day-1534156e999735fe0befad958e1447600c0c20e7.tar.xz
i2c: mv64xxx: Fix clock resource by adding an optional bus clock
On Armada 7K/8K we need to explicitly enable the bus clock. The bus clock is optional because not all the SoCs need them but at least for Armada 7K/8K it is actually mandatory. The binding documentation is updating accordingly. Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt20
-rw-r--r--drivers/i2c/busses/i2c-mv64xxx.c12
2 files changed, 31 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt b/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt
index 5c30026921ae0..0ffe65a316aee 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt
@@ -25,6 +25,15 @@ default frequency is 100kHz
whenever you're using the "allwinner,sun6i-a31-i2c"
compatible.
+ - clocks: : pointers to the reference clocks for this device, the
+ first one is the one used for the clock on the i2c bus,
+ the second one is the clock used to acces the registers
+ of the controller
+
+ - clock-names : names of used clocks, mandatory if the second clock is
+ used, the name must be "core", and "reg" (the latter is
+ only for Armada 7K/8K).
+
Examples:
i2c@11000 {
@@ -42,3 +51,14 @@ For the Armada XP:
interrupts = <29>;
clock-frequency = <100000>;
};
+
+For the Armada 7040:
+
+ i2c@701000 {
+ compatible = "marvell,mv78230-i2c";
+ reg = <0x701000 0x20>;
+ interrupts = <29>;
+ clock-frequency = <100000>;
+ clock-names = "core", "reg";
+ clocks = <&core_clock>, <&reg_clock>;
+ };
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index f69066266faa4..440fe4a96e680 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -135,6 +135,7 @@ struct mv64xxx_i2c_data {
u32 freq_m;
u32 freq_n;
struct clk *clk;
+ struct clk *reg_clk;
wait_queue_head_t waitq;
spinlock_t lock;
struct i2c_msg *msg;
@@ -894,13 +895,20 @@ mv64xxx_i2c_probe(struct platform_device *pd)
init_waitqueue_head(&drv_data->waitq);
spin_lock_init(&drv_data->lock);
- /* Not all platforms have a clk */
+ /* Not all platforms have clocks */
drv_data->clk = devm_clk_get(&pd->dev, NULL);
if (IS_ERR(drv_data->clk) && PTR_ERR(drv_data->clk) == -EPROBE_DEFER)
return -EPROBE_DEFER;
if (!IS_ERR(drv_data->clk))
clk_prepare_enable(drv_data->clk);
+ drv_data->reg_clk = devm_clk_get(&pd->dev, "reg");
+ if (IS_ERR(drv_data->reg_clk) &&
+ PTR_ERR(drv_data->reg_clk) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+ if (!IS_ERR(drv_data->reg_clk))
+ clk_prepare_enable(drv_data->reg_clk);
+
drv_data->irq = platform_get_irq(pd, 0);
if (pdata) {
@@ -950,6 +958,7 @@ exit_free_irq:
exit_reset:
reset_control_assert(drv_data->rstc);
exit_clk:
+ clk_disable_unprepare(drv_data->reg_clk);
clk_disable_unprepare(drv_data->clk);
return rc;
@@ -963,6 +972,7 @@ mv64xxx_i2c_remove(struct platform_device *dev)
i2c_del_adapter(&drv_data->adapter);
free_irq(drv_data->irq, drv_data);
reset_control_assert(drv_data->rstc);
+ clk_disable_unprepare(drv_data->reg_clk);
clk_disable_unprepare(drv_data->clk);
return 0;